Patient interface using a foam seal-forming structure

Abstract

To improve a compliance of patients with respiratory therapy.SOLUTION: A cushion assembly for a patient interface includes a foam cushion and an elastomeric support portion configured to support the foam cushion. The foam cushion is more compliant in a nasal bridge region than other regions of the cushion assembly, the nasal bridge region being a region configured to engage the patient's nasal bridge when the cushion assembly is mounted on the patient's face.SELECTED DRAWING: Figure 23

Description

[Technical Field]

[0001] 1. Technical Background 1.1 Technology field The present technology relates to one or more of the detection, diagnosis, treatment, prevention and amelioration of respiratory-related disorders. The present technology also relates to medical devices or apparatus and uses thereof. [Background technology]

[0002] 1.2 Description of Related Art 1.2.1 The human respiratory system and its diseases The body's respiratory system facilitates gas exchange. The nose and oral cavity form the entrance to a patient's airways.

[0003] These airways comprise a series of branching tubes that become narrower, shorter and more numerous the deeper they go into the lungs. The lungs' primary function is gas exchange, allowing oxygen to enter the venous blood from the air and carbon dioxide to leave. The trachea divides into the right and left main bronchi, which further divide into the terminal bronchioles. The bronchi constitute the conducting airways and do not participate in gas exchange. The airways further divide into the respiratory bronchioles and ultimately the alveoli. Gas exchange occurs in the alveolar region of the lungs, and this region is called the respiratory zone. See: Non-Patent Document 1.

[0004] There is a range of respiratory diseases. Particular diseases can be characterized by particular manifestations such as apnea, hypopnea and hyperpnea.

[0005] Examples of respiratory diseases include obstructive sleep apnea (OSA), Cheyne-Stokes respiration (CSR), respiratory failure, obesity hyperventilation syndrome (OHS), chronic obstructive pulmonary disease (COPD), neuromuscular diseases (NMD), and chest wall diseases.

[0006] Obstructive sleep apnea (OSA) is a form of sleep-disordered breathing (SDB) characterized by episodes of upper airway closure or obstruction during sleep. It results from a combination of an abnormally small upper airway and normal loss of muscle tone in the tongue region, soft palate, and posterior oropharyngeal wall during sleep. This condition causes affected patients to experience breathing pauses typically lasting 30 to 120 seconds, sometimes 200 to 300 times per night. This can result in excessive daytime sleepiness, which can contribute to cardiovascular disease and brain damage. This condition is common, particularly among middle-aged, overweight men, but patients often experience no symptoms. See U.S. Patent No. 6,244,999 (Sullivan).

[0007] Cheyne-Stokes respiration (CSR) is another form of sleep-disordered breathing. CSR is a disorder of a patient's respiratory regulator, characterized by alternating periods of waxing and waning ventilation, known as the CSR cycle. CSR is characterized by repeated deoxygenation and reaeration of arterial blood. CSR can be harmful due to repeated hypoxia. In some patients, CSR is associated with recurrent sleep arousals, which can cause severe insomnia, increased sympathetic activity, and increased afterload. See U.S. Patent No. 5,929,999 (Berthon-Jones).

[0008] Respiratory failure is a general term for respiratory disorders that refers to the inability of the lungs to take in enough oxygen or exhale enough CO2 to meet the patient's needs. Respiratory failure can include some or all of the following conditions:

[0009] Patients with respiratory failure (a type of respiratory insufficiency) may experience unusual shortness of breath during exercise.

[0010] Obesity hyperventilation syndrome (OHS) is defined as the combination of severe obesity and chronic awake hypercapnia in the absence of any other clear cause of hypoventilation. Symptoms include dyspnea, morning headache, and excessive daytime sleepiness.

[0011] Chronic obstructive pulmonary disease (COPD) encompasses any of a group of lower respiratory tract diseases that share certain common characteristics, including increased resistance to air movement, prolonged expiratory phase of breathing, and a decrease in normal lung elasticity. Examples of COPD include emphysema and chronic bronchitis. Causes of COPD include chronic smoking (the primary risk factor), occupational exposure, air pollution, and genetic factors. Symptoms include dyspnea on exertion, chronic cough, and sputum production.

[0012] Neuromuscular disease (NMD) is a broad term encompassing numerous diseases and illnesses that impair muscle function directly through intrinsic muscle pathology or indirectly through neuropathology. Some NMD patients are characterized by progressive muscle impairment, resulting in the inability to walk, wheelchair confinement, difficulty swallowing, respiratory muscle weakness, and ultimately death from respiratory failure. Neuromuscular disorders can be categorized as rapidly progressive or slowly progressive: (i) rapidly progressive disorders, characterized by muscle impairment that worsens over months and leads to death within a few years (e.g., amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD) in teenagers); (ii) variable or slowly progressive disorders, characterized by muscle impairment that worsens over years and results in only a modest reduction in life expectancy (e.g., limb-girdle, facioscapulohumeral, and myotonic muscular dystrophy). Symptoms of respiratory failure in NMD include: increasing general weakness, difficulty swallowing, difficulty breathing on exertion and at rest, fatigue, drowsiness, morning headache, and difficulty concentrating and mood changes.

[0013] Chest wall disorders are a group of thoracic deformities that result in ineffective connections between the respiratory muscles and the rib cage. These disorders are primarily characterized by restrictive obstruction and share the potential for long-term hypercapnic respiratory failure. Scoliosis and / or kyphoscoliosis can lead to severe respiratory failure. Symptoms of respiratory failure include: dyspnea on exertion, peripheral edema, orthopnea, recurrent chest infections, morning headache, fatigue, poor sleep quality, and loss of appetite.

[0014] A range of treatments are available to treat or ameliorate these conditions, and preventative treatments for respiratory disease are also available to benefit otherwise healthy individuals. However, these suffer from several deficiencies.

[0015] 1.2.2 Treatment A variety of therapies are used to treat one or more of the above respiratory disorders, such as continuous positive airway pressure (CPAP) therapy, non-invasive ventilation (NIV), and invasive ventilation (IV).

[0016] Continuous positive airway pressure (CPAP) therapy is used in the treatment of obstructive sleep apnea (OSA). Its mechanism of action is that continuous positive airway pressure functions as a pneumatic splint, for example, by pushing the soft palate and tongue forward or backward against the posterior oropharyngeal wall, thereby preventing closure of the upper airway. Because treatment of OSA with CPAP therapy can be voluntary, patients may choose not to adhere to treatment if they perceive one or more of the following about the device used to deliver the treatment: it is uncomfortable, difficult to use, expensive, or aesthetically unattractive.

[0017] Noninvasive ventilation (NIV) provides ventilatory support to a patient through the upper airway to assist the patient in breathing and / or maintain adequate oxygen levels in the body by performing some or all of the respiratory functions. Ventilatory support is provided through a noninvasive patient interface. NIV is used to treat CSR and respiratory failure in forms such as OHS, COPD, NMD, and chest wall disorders. In some forms, it can improve the comfort and effectiveness of these treatments.

[0018] Invasive ventilation (IV) provides ventilatory support to patients who are no longer able to breathe effectively on their own and may be provided using a tracheostomy tube. In some forms, the comfort and effectiveness of these treatments may be improved.

[0019] 1.2.3 Treatment System These treatments may be provided by a treatment system or device. Such systems and devices may also be used to diagnose conditions without treating them.

[0020] The treatment system may include a respiratory pressure treatment device (RPT device), an air circuit, a humidifier, a patient interface, and data management.

[0021] Another form of treatment system is a mandibular repositioning device.

[0022] 1.2.3.1 Patient Interface A patient interface may be used to provide a wearer with an interface to a respiratory appliance, for example, by providing airflow to the airway entrance. Airflow may be provided via a mask to the nose and / or mouth, a tube to the mouth, or a tracheostomy tube to the patient's trachea. Depending on the therapy being applied, the patient interface may form a seal with, for example, an area of ​​the patient's face, thereby facilitating gas delivery at a pressure sufficient to disperse with atmospheric pressure for therapy implementation (e.g., at a positive pressure of about 10 cmH2O relative to atmospheric pressure). In other forms of therapy, such as oxygen delivery, the patient interface may not include a seal sufficient to facilitate delivery of a gas supply to the airways at a positive pressure of about 10 cmH2O.

[0023] Certain other mask systems may be functionally inadequate in this field. For example, masks intended for purely decorative purposes may not be able to maintain adequate pressure. Mask systems used for underwater swimming or diving may be configured to protect against water intrusion from higher external pressures and not maintain internal air at pressures higher than ambient.

[0024] Certain masks may be clinically unsuitable for this technology (for example, if the mask blocks airflow through the nose and only allows airflow through the mouth).

[0025] In certain masks, the patient must insert part of the mask structure into their mouth and create and maintain a seal via their lips, which may be uncomfortable or impractical in this technology.

[0026] Certain masks may be impractical for use while sleeping (eg, when sleeping on one's side in bed with one's head resting on a pillow).

[0027] There are multiple challenges in designing a patient interface. The face has a complex three-dimensional shape. The size and shape of the nose and head vary greatly between individuals. Because the head contains bone, cartilage, and soft tissue, different regions of the face respond differently to mechanical forces. That is, the chin or mandible can move relative to the other bones of the skull. The entire head can move throughout the respiratory treatment period.

[0028] These challenges can lead to one or more of the following: some masks can be intrusive, aesthetically undesirable, costly, poor fit, difficult to use, and uncomfortable, especially if worn for extended periods or if the patient is unfamiliar with the system. If the wrong size mask is used, this can lead to poor fit, reduced comfort, and poor patient outcomes. While masks specifically designed for aviators, personal protective equipment (e.g., filter masks), SCUBA masks, or anesthesia administration masks may be durable for their intended use, such masks may be undesirably uncomfortable to wear for extended periods (e.g., several hours). Such discomfort can reduce patient compliance with treatment. This is especially true if the mask must be worn while sleeping.

[0029] CPAP therapy is highly effective in treating certain respiratory conditions when patients comply with the therapy. If the mask is uncomfortable or difficult to use, patients may not comply with the therapy. Because patients are often encouraged to clean their masks regularly, if the mask is difficult to clean (e.g., difficult to assemble or disassemble), patients may not be able to clean the mask, which may affect patient compliance.

[0030] Masks for other uses (e.g., aviators) may be unsuitable for use in treating sleep-disordered breathing, and masks designed for use in treating sleep-disordered breathing may be suitable for other uses.

[0031] For these reasons, patient interfaces for CPAP delivery during sleep form a distinct field.

[0032] 1.2.3.1.1 Seal-forming part The patient interface may include a seal-forming portion. Because the patient interface is in direct contact with the patient's face, the shape and configuration of the seal-forming portion may have a direct impact on the effectiveness and comfort of the patient interface.

[0033] Patient interfaces can be characterized in part according to the design intent of where the seal-forming portion engages with the face during use. In one form of patient interface, the seal-forming portion can include a first sub-portion for forming a seal around the left nostril and a second sub-portion for forming a seal around the right nostril. In one form of patient interface, the seal-forming portion can include a single element that surrounds both nostrils during use. Such a single element can be designed to rest, for example, on the upper lip region and nasal bridge region of the face. In one form of patient interface, the seal-forming portion can include an element that surrounds the oral cavity during use, for example, by forming a seal over the lower lip region of the face. In one form of patient interface, the seal-forming portion can include a single element that surrounds both nostrils and the oral cavity during use. These different types of patient interfaces can be known by various names depending on their manufacturers, such as nasal masks, full face masks, nasal pillows, nasal puffs, and oronasal masks.

[0034] A seal-forming portion that may be effective in one area of ​​a patient's face may be inadequate in another area due to, for example, different shapes, structures, variability, and sensitive areas of the patient's face. For example, a seal on swimming goggles that rests on the patient's forehead may be inadequate for use on the patient's nose.

[0035] A particular seal-forming portion may be designed for mass production so that one design will fit, be comfortable, and be effective for a wide range of different face shapes and sizes. To the extent there is a mismatch between the shape of the patient's face and the seal-forming portion of the mass-manufactured patient interface, one or both may need to be adapted to form a seal.

[0036] One type of seal-forming portion extends around the periphery of the patient interface and is intended to seal against the patient's face when force is applied to the patient interface with the seal-forming portion against the patient's face while the seal-forming portion is engaged against the patient's face. This seal-forming portion may include an air- or fluid-filled cushion, or may include a molded or formed surface of a resilient sealing element constructed of an elastomer such as rubber. With this type of seal-forming portion, if the fit is improper, a gap will form between the seal-forming portion and the face, requiring additional force to press the patient interface against the face to achieve a seal.

[0037] Another type of seal-forming part uses a thin flap seal positioned around the periphery of the mask to provide a self-sealing seal against the patient's face when positive pressure is applied within the mask. As with the previous type of seal-forming part, poor fit between the face and the mask can require additional force to achieve a seal or the mask may leak. Furthermore, if the shape of the seal-forming part does not match the shape of the patient, the seal-forming part may fold or buckle during use, causing leakage.

[0038] Other types of seal-forming portions may include friction-fit elements that are inserted into the nostrils, for example, but some patients find these seal-forming portions uncomfortable.

[0039] Another form of seal-forming portion may use adhesives to achieve a seal, as some patients find it inconvenient to constantly apply and remove adhesives from their face.

[0040] A range of patient interface seal forming techniques are disclosed in the following patent applications (assigned to ResMed Limited: US Pat. No. 5,623,999; US Pat. No. 5,623,999; and US Pat. No. 5,623,999).

[0041] One form of nasal pillow is found in the Adam line manufactured by Puritan Bennett. Another nasal pillow or nasal puff is the subject of US Pat. No. 6,223,999 (Trimble et al.), assigned to Puritan-Bennett Corporation.

[0042] ResMed Limited manufactures the following products that use nasal pillows: SWIFT® nasal pillows mask, SWIFT® II nasal pillows mask, SWIFT® LT nasal pillows mask, SWIFT® FX nasal pillows mask, and MIRAGE LIBERTY® full face mask. Examples of nasal pillows masks are described in the following patent applications assigned to ResMed Limited: U.S. Patent No. 5,623,999 (depicting, among other things, aspects of ResMed Limited's SWIFT® nasal pillows), U.S. Patent No. 5,623,999 (depicting, among other things, aspects of ResMed Limited's SWIFT® LT nasal pillows), U.S. Patent No. 5,623,999 (depicting, among other things, aspects of ResMed Limited's MIRAGE LIBERTY® full face mask), and U.S. Patent No. 5,623,999 (depicting, among other things, aspects of ResMed Limited's SWIFT® FX nasal pillows).

[0043] 1.2.3.1.2 Positioning and stabilization The seal-forming portions of patient interfaces used in positive air therapy are subjected to corresponding air pressure forces that disrupt the seal, and therefore a variety of techniques are used to position the seal-forming portions and maintain a seal against the appropriate portion of the face.

[0044] In one technique, adhesives are used, see, for example, US Patent No. 5,929,999, however, adhesives can be uncomfortable.

[0045] Another technique involves the use of one or more straps and / or stabilizing harnesses, many of which suffer from one or more of the following problems: poor fit, bulky, uncomfortable, and cumbersome.

[0046] 1.2.3.2 Respiratory Pressure Therapy (RPT) Devices Respiratory pressure therapy (RPT) devices can be used to deliver one or more of the above-mentioned therapies, for example, by generating a flow of air delivery to the airway entrance. This flow of air can be pressurized. Examples of RPT devices include CPAP devices and mechanical ventilators.

[0047] Air pressure generators are known for a wide range of applications (e.g., industrial-scale ventilation systems). However, air pressure generators for medical applications have specific requirements that cannot be met by more common air pressure generators (e.g., the reliability, size, and weight requirements of medical equipment). In addition, even devices designed for medical treatment may suffer from deficiencies related to one or more of the following: comfort, noise, ease of use, effectiveness, size, weight, manufacturability, cost, and reliability.

[0048] One example of a special requirement for a particular RPT device is acoustic noise.

[0049] Table of noise output levels of conventional RPT devices (measured on one sample only at 10cmH2O in CPAP mode using the test method specified in ISO3744).

[0050] [Table 1]

[0051] One known RPT device used to treat sleep-disordered breathing is the S9 Sleep Therapy System (manufactured by ResMed Limited). Another example of an RPT device is a ventilator. Ventilators (e.g., the ResMed Stellar® series of adult and pediatric ventilators) can provide invasive and non-invasive independent respiratory support for patients for a range of conditions, including, but not limited to, NMD, OHS, and COPD.

[0052] The ResMed Elisee® 150 ventilator and ResMed VSIII® ventilators can provide invasive and non-invasive dependent respiratory support suitable for adult or pediatric patients for the treatment of multiple conditions. These ventilators offer volumetric and pressure ventilation modes using single or dual limb circuits. RPT devices typically include a pressure generator (e.g., an electric blower or compressed gas reservoir) and are configured to deliver airflow to the patient's airway. In some cases, the airflow can be delivered to the patient's airway at positive pressure. The outlet of the RPT device is connected via an air circuit to a patient interface, as described above.

[0053] A device designer may be presented with a myriad of choices. Often, conflicting design criteria may make certain design choices unconventional or unavoidable. Furthermore, the comfort and effectiveness of a particular implementation may be significantly affected by minor changes in one or more parameters.

[0054] 1.2.3.3 Humidifier Delivery of airflow without humidification can lead to dryness of the airway. When a humidifier is used with an RPT device and patient interface, humidified gas is produced, minimizing drying of the nasal mucosa and increasing comfort of the patient's airway. Additionally, in cooler climates, the application of warm air to the facial area surrounding the patient interface generally provides more comfort than cool air.

[0055] A range of artificial humidification devices and systems are known, but do not meet the special requirements of medical humidifiers.

[0056] Medical humidifiers are typically used when a patient is sleeping or resting (e.g., in a hospital) to increase the humidity and / or temperature of an air stream relative to the ambient air when needed. Bedside medical humidifiers may be compact. Medical humidifiers may be configured to only humidify and / or heat the air stream delivered to the patient, not the patient's surroundings. For example, while room-based systems (e.g., saunas, air conditioners, or evaporative coolers) may also humidify the air breathed into the patient's body, these systems also humidify and / or heat the entire room, which may be uncomfortable for occupants. Additionally, medical humidifiers may have more stringent safety constraints than industrial humidifiers.

[0057] Although many medical humidifiers are known, such medical humidifiers may suffer from one or more deficiencies, such that some provide inadequate humidification or are difficult or inconvenient for the patient to use.

[0058] 1.2.3.4 Data Management For clinical reasons, data may be obtained to determine whether a patient prescribed respiratory therapy is "compliant" (e.g., whether the patient adheres to certain "compliance rules" for their RPT device). An example of a compliance rule for CPAP therapy may require a patient to use the RPT device for at least four hours per night for at least 21 days out of 30 consecutive days to be considered compliant. To determine patient compliance, a provider of the RPT device (e.g., a healthcare provider) may manually obtain data describing the patient's treatment with the RPT device, calculate usage rates over a given period, and compare this to the compliance rules. Once the healthcare provider determines that the patient has used their RPT device in accordance with the compliance rules, the healthcare provider may notify a third party that the patient is compliant.

[0059] There may be other aspects of patient care that benefit from communication of treatment data to third parties or external systems.

[0060] Existing processes for communicating and managing such data can be costly, time consuming, and / or error prone.

[0061] 1.2.3.5 Mandibular repositioning A mandibular repositioning device (MRD) or mandibular advancement device (MAD) is one treatment option for sleep apnea and snoring. It is an adjustable oral appliance available from dentists or other suppliers that holds the mandible (lower jaw) in an anterior position during sleep. MRDs are removable devices that are inserted into the mouth before a patient goes to sleep and removed afterward. As such, MRDs are not designed for full-time wear. MRDs can be custom-made or manufactured in standard forms and include bite impression sections designed to fit the patient's teeth. This mechanical protrusion from the mandible expands the space behind the tongue and applies tension on the pharyngeal walls, reducing airway collapse and palatal vibration.

[0062] In certain embodiments, the mandibular advancement device may include an upper splint intended to engage or mate with teeth on the upper jaw or maxilla, and a lower splint intended to engage or mate with teeth on the upper jaw or mandible. The upper and lower splints are laterally connected to each other via a pair of connecting rods that are fixed symmetrically on the upper and lower splints.

[0063] In such a design, the length of the connecting rod is selected so that the mandible is held in a forward position when the MRD is placed in the patient's mouth. The length of the connecting rod can be adjusted to change the level of mandibular protrusion. The dentist can determine the level of protrusion required for the mandible, and the length of the connecting rod is then determined.

[0064] Some MRDs are configured to push the mandible forward relative to the maxilla, while others, such as the ResMed Narval CC® MRD, are designed to hold the mandible in a forward position. The devices also reduce or minimize dental and temporomandibular joint (TMJ) side effects. As such, the devices are configured to minimize or prevent any movement of one or more teeth.

[0065] 1.2.3.6 Ventilation Technology Some forms of treatment systems may include a vent to push out exhaled carbon dioxide, which may allow gas flow from an interior space of the patient interface (e.g., a plenum chamber) to an exterior of the patient interface (e.g., ambient).

[0066] The vents may include orifices through which gas can flow when the mask is in use. Many such vents are noisy. Others may become blocked during use, resulting in insufficient pumping. Some vents may disrupt sleep for the patient 1000 and bed companion 1100, for example, due to noise or concentrated airflow.

[0067] ResMed Limited has developed several improved mask ventilation technologies, see: US Patent Nos. 5,629,999; ... and 5,629,999.

[0068] Conventional mask noise table (ISO17510-2:2007, 10cmH2O pressure at 1m)

[0069] [Table 2]

[0070] (*Only one sample was measured at 10cmH2O in CPAP mode using the test method specified in ISO3744) Various sound pressure values ​​for various subjects are shown in the list below.

[0071] [Table 3]

[0072] 1.2.4 Diagnostic and Monitoring Systems Polysomnography (PSG) is a conventional system for diagnosing and monitoring cardiopulmonary diseases and typically requires specialized clinical staff for system application. PSG typically involves placing 15–20 contact sensors on the body to record various body signals (e.g., electroencephalography (EEG), electrocardiography (ECG), electrooculography (EOG), and electromyography (EMG)). PSG for sleep-disordered breathing requires patients to be observed for two nights in a specialized hospital: the first night for pure diagnosis and the second night for clinician-assisted titration of treatment parameters. Therefore, PSG is expensive and inconvenient. PSG is particularly unsuitable for home sleep testing.

[0073] A clinical expert may adequately diagnose or monitor a patient based on visual observation of the PSG signal. However, there are situations where a clinical expert is not available or cannot be paid for. Different clinical experts may have different opinions about a patient's condition. Furthermore, some clinical experts may apply different criteria at different times. [Prior art documents] [Patent documents]

[0074] [Patent Document 1] U.S. Patent No. 4,944,310 [Patent Document 2] U.S. Patent No. 6,532,959 [Patent Document 3] International Publication No. 1998 / 004310 [Patent Document 4] International Publication No. 2006 / 074513 [Patent Document 5] International Publication No. 2010 / 135785 [Patent Document 6] U.S. Patent No. 4,782,832 [Patent Document 7] International Publication No. 2004 / 073778 [Patent Document 8] U.S. Patent Application No. 2009 / 0044808 [Patent Document 9] International Publication No. 2005 / 063,328 [Patent Document 10] International Publication No. 2006 / 130903 [Patent Document 11] International Publication No. 2009 / 052560 [Patent Document 12] US Patent Application Publication No. 2010 / 0000534 [Patent Document 13] International Publication No. 1998 / 034665 [Patent Document 14] International Publication No. 2000 / 078381 [Patent Document 15] U.S. Patent No. 6,581,594 [Patent Document 16] U.S. Patent Application Publication No. 2009 / 0050156 [Patent Document 17] U.S. Patent Application Publication No. 2009 / 0044808 [Non-patent literature]

[0075] [Non-Patent Document 1] “Respiratory Physiology”, by John B. West, Lippincott Williams & Wilkins, 9th edition published 2012 Summary of the Invention [Problem to be solved by the invention]

[0076] 2. Brief description of the technology The present technology relates to the provision of medical devices for use in the diagnosis, amelioration, treatment or prevention of respiratory disorders, which medical devices have one or more of improved comfort, cost, effectiveness, ease of use and manufacturability.

[0077] A first aspect of the present technology relates to devices used in the diagnosis, amelioration, treatment or prevention of respiratory disorders.

[0078] Another aspect of the present technology relates to methods for use in the diagnosis, amelioration, treatment or prevention of respiratory disorders.

[0079] An aspect of certain forms of the present technology is to provide methods and / or devices that improve patient compliance with respiratory therapy. [Means for solving the problem]

[0080] One aspect of the present technology relates to a patient interface that includes: a plenum chamber pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, the plenum chamber including a plenum chamber inlet port, the plenum chamber inlet port sized and configured to receive an airflow at the therapeutic pressure for breathing by the patient; and a sealing structure constructed and arranged to be shaped to form a seal with an area of ​​the patient's face about an entrance to the patient's airways, whereby the airflow at the therapeutic pressure is delivered to at least an entrance to the patient's nasal passages, the seal being formed to prevent air from exiting the plenum chamber between the sealing structure and the area of ​​the patient's face, the sealing structure being configured to seal the plenum chamber throughout the patient's respiratory cycle, in use. a positioning and stabilizing structure for maintaining the sealing structure in a therapeutically effective position on a patient's head when the patient is lying in a lateral sleeping position and when the patient is lying in a supine sleeping position, the positioning and stabilizing structure including a low-profile side portion and a low-profile rear portion; an exhalation vent structure configured to allow continuous ventilatory flow from within the plenum chamber to ambient when pressure within the plenum chamber is positive relative to ambient, the vent structure configured such that the ventilating flow rate is sufficient to assist in reducing rebreathing of exhaled CO2 by the patient during both patient inhalation and exhalation while maintaining therapeutic pressure within the plenum chamber in use, wherein the sealing structure includes a sealing surface that forms a seal against the patient's face in use, and the sealing structure includes a tether extending between a first inner surface region of the sealing structure opposite the sealing surface and a second inner surface region of the patient interface to resist deformation of the sealing structure.

[0081] In embodiments, (a) the sealing structure may include a second interior surface region, the second interior surface region spaced apart from the first interior surface region; (b) the plenum chamber may include a second interior surface region, the second interior surface region spaced apart from the first interior surface region; (c) the tether and the sealing structure may comprise a unitary structure formed from a homogenous material; (d) the homogenous material may be silicone rubber; (e) the silicone rubber may be liquid silicone rubber or compression molded silicone rubber; (f) the sealing structure may include a sealing flap at an edge region, the sealing flap shaped and arranged to seal against at least the sides of the patient's nose in use, the sealing flap being thinner than adjacent regions of the sealing structure; and (g) the first interior surface region may be configured such that the tether is spaced inwardly from the sealing flap. (h) the tether may extend from the sealing structure proximate at the edge region such that the tether forms an extension of the sealing surface; (i) the tether may include an inner surface and the sealing structure may include an inner surface; (j) the inner surface of the tether is adjacent to and separated from the inner surface of the sealing structure; (k) the plenum chamber may be comprised of a transparent material; (l) the patient interface may be configured such that no part of the patient interface structure enters the oral cavity when in use; (m) the sealing structure may be configured such that it does not extend into the patient's airway when in use; (n) the sealing structure may be configured such that it does not extend below the mental protuberance region when in use; and / or (o) the plenum chamber may be configured so as not to cover the eyes when in use.

[0082] Another aspect of the present technology relates to an assembly for a patient interface including: a plenum chamber pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, the plenum chamber including a plenum chamber inlet port sized and configured to receive an airflow at the therapeutic pressure to be breathed by the patient; and a sealing structure constructed and arranged to be shaped to form a seal with an area of ​​the patient's face about an entrance to the patient's airways, whereby the airflow at the therapeutic pressure is delivered to at least an entrance to the patient's nasal passages, the seal being shaped to prevent air from exiting the plenum chamber between the sealing structure and the area of ​​the patient's face, the sealing structure constructed and arranged to maintain the therapeutic pressure in the plenum chamber throughout the patient's respiratory cycle in use, the sealing structure including a sealing surface that forms the seal against the patient's face in use, and a connecting portion extending between a first inner surface area of ​​the sealing structure opposite the sealing surface and a second inner surface area of ​​the assembly such that the connecting portion is resistant to deformation of the sealing structure.

[0083] In embodiments, (a) the sealing structure may include a second inner surface region, the second inner surface region spaced apart from the first inner surface region; (b) the plenum chamber may include a second inner surface region, the second inner surface region spaced apart from the first inner surface region; (c) the connection portion and the sealing structure may comprise a unitary structure formed from a homogenous material; (d) the homogenous material may be silicone rubber; (e) the silicone rubber may be liquid silicone rubber or compression molded silicone rubber; (f) the sealing structure may include a sealing flap at an edge region, the sealing flap shaped and positioned to seal against at least a side of the patient's nose in use, the sealing flap being thinner than adjacent regions of the sealing structure; and (g) the first inner surface region may include a connection portion spaced apart from the sealing flap. (h) the connecting portion may extend proximally from the sealing structure at the edge region such that the connecting portion forms an extension of the sealing surface; (i) the connecting portion may include an inner surface and the sealing structure may include an inner surface, the inner surface of the connecting portion being adjacent to and separated from the inner surface of the sealing structure; (j) the plenum chamber may be constructed from a transparent material; (k) the assembly may be configured so that no part of the assembly enters the oral cavity when in use; (l) the sealing structure may be configured so that it does not extend into the patient's airway when in use; (m) the sealing structure may be configured so that it does not extend below the mental protuberance region when in use; and / or (n) the plenum chamber is configured so that it does not cover the eyes when in use.

[0084] One form of the present technology includes a sealing structure for sealing against a user's face around the user's airway, the sealing structure including a flap or membrane that extends inwardly into the user's airway and includes an attachment structure to prevent the inner boundary of the flap or membrane from being blown outward (e.g., double-folded backward) due to internal pressurization.

[0085] In embodiments, the attachment structure may include one or more ribs / tethers / connectors / connecting structures, flaps extending from the membrane and folded inward and attached to another structure to form a tube or loop, or a tube positioned underneath and attached to the membrane.

[0086] Another aspect of one form of the present technology is a sealing structure for a patient interface for sealed delivery of airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the entrances to the patient's nasal passages. The patient interface is configured to maintain a therapeutic pressure in use in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle as the patient sleeps, thereby improving sleep-disordered breathing. The sealing structure includes a sealing surface configured to form a seal around the entrance to the patient's airways, and a loop. The loop folds inwardly around the periphery of the sealing structure to form a substantially tubular structure such that the loop is continuous, and the loop includes a portion of the sealing surface.

[0087] In some embodiments, (a) the sealing structure further includes a sealing flap projecting toward an inner periphery of the sealing structure, (b) the sealing flap is configured to form a seal against the side of the patient's nose above the nasal bone, (c) the sealing flap is configured to avoid sealing against the ala, (d) a portion of the sealing surface is more flexible relative to the remainder of the portion of the loop sealing surface and includes a thinner wall than the remainder of the loop, (e) the portion of the sealing surface includes a thicker wall than the remainder of the loop, (f) the loop is positioned to contact the side wall of the nose, including the ala, (g) the loop provides a continuous surface configured to maintain contact with the side of the patient's nose above the nasal bone, (h) the loop includes at least one closed end, and (i) the loop is configured to fold the sealing structure inward to (j) forming a connection point on an inner surface of the sealing structure, the connection point being positioned relative to the sealing surface to apply sufficient tension to the loop to neutralize outward rupture of the sealing surface when therapeutic pressure is applied to the inner surface of the loop, (k) the loop forming a predetermined angle at the connection point, the predetermined angle determining the tension in the loop when therapeutic pressure is applied, (l) the connection point being adjustable, (m) the connection point being a releasable connection, (n) the sealing structure further comprising a second connection point, (o) the sealing surface including a low friction region to reduce contact with the patient's face, (p) the low friction region being a matte surface, (q) the low friction region being adapted to allow the side of the patient's nose to slide freely against the sealing surface, and / or (r) the loop providing a borderless sealing surface.

[0088] Another aspect of one form of the present technology is a patient interface for sealingly delivering a flow of air at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, the entrance to the patient's airways including at least the patient's nasal inlets. The patient interface is configured to maintain a therapeutic pressure in use in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle as the patient sleeps, thereby improving sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a sealing surface configured to form a seal around the entrance to the patient's airways, and a loop that folds the sealing structure inwardly around its periphery to form a substantially tubular structure such that the loop is continuous, the loop including a portion of the sealing surface. The patient interface further includes a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and an area surrounding the entrance to the patient's airway while maintaining a therapeutic pressure at the entrance to the patient's airway; a plenum chamber that is pressurized in use to a pressure above ambient pressure; and a gas exhalation vent configured to allow a flow of the patient's exhaled CO2 out of the patient interface, thereby minimizing rebreathing of exhaled CO2 by the patient.

[0089] In some embodiments, (a) the sealing flap protrudes into the inner periphery of the sealing structure, (b) the sealing flap is configured to form a seal adjacent to the side of the nose above the maxilla against the side of the nose above the nasal bone when the patient's medial canthus is pressed against it, (c) the sealing flap is configured to avoid sealing with the wings, (d) a portion of the sealing surface is more flexible than the remainder of the loop, (e) the portion of the sealing surface includes a thinner wall than the remainder of the loop, (f) the portion of the sealing surface includes a thicker wall than the remainder of the loop, (g) the sealing surface includes a low friction area to reduce contact with the patient's face, (h) the low friction area is a matte surface, (i) the low friction area is adapted to allow the side of the patient's nose to slide freely against the sealing surface, (j) the first loop defines an area of ​​the sealing structure adapted to contact the patient's face, and (k) the second loop defines an area of ​​the sealing structure adapted to contact the patient's face. The first portion and the second portion are part of a region of the sealing structure adapted to contact the patient's face, (l) the first loop is continuous, (m) the second loop is positioned in contact with or alongside the patient's nose, (n) the second loop is positioned such that the substantially tubular structure is adapted to contact or be positioned alongside the patient's nose, (o) the substantially tubular structure is adapted to be positioned substantially parallel to the side of the patient's nose, (p) the sealing structure further comprises a second one of the second loops, (g) the substantially tubular structure comprises a hollow interior adapted to be in fluid communication with a pressure above ambient pressure, (r) the substantially tubular structure comprises two open ends, and / or (s) the second loop is adapted to prevent rupture of the second loop when the patient interface is internally pressurized or adjusted by the patient.

[0090] Another aspect of one form of the present technology is a patient interface for sealingly delivering airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the entrances to the patient's nostrils. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's breathing cycle while the patient is sleeping, thereby improving sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a face-contacting portion adapted to contact the periphery of the entrance to the patient's airways and a first substantially cylindrical region having at least a continuous circumference. A portion of the cylindrical region includes a portion of the face-contacting portion. The patient interface further includes a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and an area surrounding the entrance to the patient's airway while maintaining a therapeutic pressure at the entrance to the patient's airway; a plenum chamber that is pressurized in use to a pressure above ambient pressure; and a gas exhalation vent configured to allow a flow of the patient's exhaled CO2 out of the patient interface, thereby minimizing rebreathing of exhaled CO2 by the patient.

[0091] In embodiments, (a) the sealing structure includes an unrestricted edge adjacent an end of the first substantially cylindrical region, (b) the sealing structure includes an unrestricted edge around the entire periphery of the entrance to the patient's airway except for the first substantially cylindrical region, (c) the face-contacting portion forms a convex surface adapted to contact the patient's face, (d) the first substantially cylindrical region is positioned in contact with or alongside the patient's wings, (e) the first substantially cylindrical region is positioned substantially parallel to the patient's wings, and (f) the patient interface is positioned between the second cylindrical region and the third cylindrical region. (g) the cylindrical region includes a second substantially cylindrical region having a second continuous circumference, a portion of the second cylindrical region including a second portion of the face contacting portion; (h) the first substantially cylindrical region includes a hollow interior adapted to be in fluid communication with a pressure above ambient pressure; (i) the first substantially cylindrical region includes two open ends; and / or (j) the first substantially cylindrical region is adapted to prevent rupture of the face contacting portion when the patient interface is internally pressurized or adjusted by the patient.

[0092] Another aspect of one form of the present technology is a patient interface for sealingly delivering a flow of air at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the entrances to the patient's nostrils. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, thereby improving sleep-disordered breathing. The patient interface includes: a sealing structure including a double-folded material to form a continuous tubular shape, the sealing structure configured such that only a portion of the circumference of the tubular shape contacts the patient's face; a positioning and stabilizing structure that maintains sealing contact between the sealing structure and the nasal passages around the entrance to the patient's airways while maintaining the therapeutic pressure at the entrance to the patient's airways; a plenum chamber that is pressurized to a pressure above ambient pressure in use; and a gas outlet vent configured to allow the patient's exhaled CO2 to flow out of the patient interface, thereby minimizing rebreathing of the exhaled CO2 by the patient, the interior of the tubular shape being adapted to be in fluid communication with a pressure above ambient pressure.

[0093] In embodiments, (a) the continuous tubular shape has an inner tubular surface and an outer tubular surface, the inner tubular surface adapted to be exposed to a pressure above ambient pressure in use, a first portion of the outer tubular surface adapted to be exposed to ambient pressure in use, and a second portion of the outer tubular surface adapted to be exposed to a pressure above ambient pressure in use; (b) the sealing structure further comprises a surface that contacts the periphery of the patient's airway, the portion of the continuous tubular shape being a portion of the surface; (c) the continuous tubular shape is open on at least one end; and (d) the continuous tubular shape is open on two ends. (e) the continuous tubular shape is adapted to line up with the patient's wings; (f) the continuous tubular shape is adapted to contact the patient's wings; (g) the material is folded to form a second continuous tubular shape, where only a portion of the circumference of the second continuous tubular shape is configured to contact the patient's face; (h) the continuous tubular shape is adapted to rest on opposite sides of the patient's nose; and / or (i) the continuous tubular shape is adapted to prevent the material from rupturing when the patient interface is internally pressurized or adjusted by the patient.

[0094] Another aspect of one form of the present technology is a patient interface for sealingly delivering airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril entrances. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, thereby improving sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a first face-contacting portion with an unconnected edge at an inner boundary of the sealing structure and a second face-contacting portion that is part of a tubular structure, the first face-contacting portion and the second face-contacting portion each forming a continuous membrane configured to contact the patient's face around the entrance to the patient's airways. The patient interface further includes a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and an area surrounding the entrance to the patient's airway while maintaining a therapeutic pressure at the entrance to the patient's airway; a plenum chamber that is pressurized in use to a pressure above ambient pressure; and a gas exhalation vent configured to allow a flow of the patient's exhaled CO2 out of the patient interface, thereby minimizing rebreathing of exhaled CO2 by the patient.

[0095] In embodiments, (a) the patient interface further includes a plurality of second face-contacting regions, (b) the second face-contacting regions are adapted to contact the patient's face adjacent to or on the patient's wings, and / or (c) the tubular structure is adapted to prevent rupture of the continuous membrane when the patient interface is internally pressurized or adjusted by the patient.

[0096] Another aspect of one form of the present technology is a patient interface for sealingly delivering a flow of air at a continuously positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril entrances. The patient interface is configured, in use, to maintain a treatment pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, to ameliorate sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a sealing membrane and a flap. The flap is attached to the sealing membrane on a first end and to another structure on a second end to prevent the sealing membrane from bursting outward due to the treatment pressure. The patient interface further includes a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and an area surrounding the entrance to the patient's airway while maintaining a therapeutic pressure at the entrance to the patient's airway; a plenum chamber that is pressurized in use to a pressure above ambient pressure; and a gas exhalation vent configured to allow a flow of the patient's exhaled CO2 out of the patient interface, thereby minimizing rebreathing of exhaled CO2 by the patient.

[0097] In embodiments, (a) the sealing membrane and the flap form part of a tubular structure, and / or (b) the sealing membrane is adapted to contact the entire periphery of the entrance to the patient's airway, and the flap is provided for only a portion of the periphery.

[0098] Another aspect of one form of the present technology is a patient interface for sealingly delivering a flow of air at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril inlets. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, thereby improving sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a sealing membrane adapted to contact the patient's face around the entrance to the patient's airways, and a cylindrical area attached to the underside of the sealing membrane. The patient interface further includes: a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and the area around the entrance to the patient's airways while maintaining the therapeutic pressure at the entrance to the patient's airways; a plenum chamber that is pressurized to a pressure above ambient pressure in use; and a gas outlet vent configured to allow a flow of the patient's exhaled CO2 to flow out of the patient interface, thereby minimizing rebreathing of the exhaled CO2 by the patient.

[0099] In some embodiments, (a) the cylindrical region is positioned adjacent to the patient's wing; (b) the cylindrical region includes an axis that is substantially parallel to the patient's wing; (c) the cylindrical region is adapted to prevent the sealing membrane from being blown away from an entrance to the patient's airway when the plenum chamber is pressurized above ambient pressure; and / or (d) the sealing membrane includes an unconnected edge all around the entrance to the patient's airway.

[0100] Another aspect of one form of the present technology is a patient interface for sealingly delivering airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the entrances to the patient's nostrils. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 3 cmH2O to about 40 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, thereby improving sleep-disordered breathing. The patient interface includes a sealing structure for sealing the patient interface against the patient's face. The sealing structure includes a sealing membrane having inner and outer surfaces adapted to contact the patient's face around the entrance to the patient's airways, and ribs attached to an underside of the inner surface such that the ribs resist deformation of the sealing membrane when pressure is applied to the inner surface. The patient interface further includes a positioning and stabilizing structure for maintaining sealing contact between the sealing structure and an area surrounding the entrance to the patient's airway while maintaining a therapeutic pressure at the entrance to the patient's airway; a plenum chamber that is pressurized in use to a pressure above ambient pressure; and a gas exhalation vent configured to allow a flow of the patient's exhaled CO2 out of the patient interface, thereby minimizing rebreathing of exhaled CO2 by the patient.

[0101] In embodiments, (a) the outer surface includes convex portions, (b) the inner surface has concave portions, (c) the concave portions and convex portions are disposed directly opposite each other on the outer surface and inner surface, respectively, and the ribs are attached to the inner surface at the concave portions, (d) the ribs are readily crushed by forces applied to the patient interface when the patient interface is held by a patient, (e) the patient interface further includes a plurality of ribs, (f) the ribs fit adjacent to the patient's nose, (g) the ribs are adapted to prevent rupture of the sealing membrane when the patient interface is internally pressurized or adjusted by the patient, and / or (h) the ribs are substantially perpendicular to the inner surface.

[0102] Another aspect of one form of the present technology relates to a cushion assembly for a patient interface for sealingly delivering airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril entrances. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, to improve sleep-disordered breathing. The cushion assembly includes a foam cushion and an elastomeric support section configured to support the foam cushion. The foam cushion may be more compliant in a nose bridge region than in other regions of the cushion assembly, the nose bridge region being a region configured to engage the patient's nose bridge when the cushion assembly is placed on the patient's face.

[0103] Another aspect of one form of the present technology relates to a cushion assembly for a patient interface for delivering a flow of air at a continuously positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril entrances, in a sealed manner. The patient interface is configured, in use, to maintain a therapeutic pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, to improve sleep-disordered breathing. The cushion assembly includes a foam cushion, and an elastomeric support section is configured to support the foam cushion. The elastomeric support section can provide varying levels of support to the foam cushion in different regions of the cushion assembly.

[0104] Another aspect of one form of the present technology relates to a cushion assembly for a patient interface for sealingly delivering airflow at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the patient's nostril entrances. The patient interface is configured to maintain a therapeutic pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure throughout the patient's respiratory cycle while the patient is sleeping, in use, to improve sleep-disordered breathing. The cushion assembly may include a foam cushion and an elastomeric support section configured to support the foam cushion. The cushion assembly is bisected by a sagittal plane having lines of contact with the foam cushion at only the upper and lower contact points. The depth of the support section is greatest in an upper region including the upper contact point, and the elastomeric wall thickness of the elastomeric support section is smallest in the upper region.

[0105] Another aspect of one form of the present technology is a patient interface that is molded or otherwise constructed with a peripheral shape that is complimentary to the shape of the intended wearer.

[0106] One aspect of the present technology is a method for manufacturing a device.

[0107] One aspect of certain forms of the present technology is a medical device that is easy to use, for example, by individuals without medical training, individuals with limited dexterity or acumen, or individuals with limited experience using such medical devices.

[0108] One aspect of one form of the present technology is a portable RPT device that can be carried by a person (e.g., around the home).

[0109] An aspect of one form of the present technology is a patient interface that can be cleaned at the patient's home, for example with soapy water, without the need for special cleaning equipment.An aspect of one form of the present technology is a patient interface that can be cleaned at the patient's home, for example with soapy water, without the need for special cleaning equipment.

[0110] The methods, systems, devices, and apparatus described herein may enable improved functionality in processors (e.g., processors of special purpose computers, respiratory monitors, and / or respiratory treatment devices). Additionally, the described methods, systems, devices, and apparatus enable advancements in the art of automated management, monitoring, and / or treatment of respiratory conditions (e.g., sleep disordered breathing).

[0111] Of course, some of the above aspects may form sub-aspects of the present technology, and various sub-aspects and / or aspects may be combined in various ways to form further aspects or sub-aspects of the present technology.

[0112] Other features of the present technology will become apparent in light of the information contained in the following detailed description, abstract, drawings, and claims. [Brief explanation of the drawings]

[0113] 3 Brief description of the drawings The present technology is illustrated by way of example and not limitation in the accompanying drawings, in which like reference numerals include like elements: 3.1 Treatment System [Figure 1A] 1A shows a system including a patient 1000 wearing a patient interface 3000, which takes the form of nasal pillows and receives air at positive pressure supplied by an RPT device 4000. The air from the RPT device 4000 is humidified by a humidifier 5000 and travels along an air circuit 4170 to the patient 1000. A bed companion 1100 is also shown. The patient is sleeping in a supine sleeping position. [Figure 1B] 1B shows a system including a patient 1000 wearing a patient interface 3000. The system takes the form of a nasal mask and receives air at positive pressure supplied by an RPT device 4000. The air from the RPT device is humidified by a humidifier 5000 and travels along an air circuit 4170 to the patient 1000. [Figure 1C] 1C shows a system including a patient 1000 wearing a patient interface 3000. The patient interface 3000 takes the form of a full face mask and receives a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified by a humidifier 5000 and travels along an air circuit 4170 to the patient 1000. The patient is sleeping in a lateral sleeping position. 3.2 Respiratory System and Facial Anatomy [Figure 2A] Figure 2A shows an overview of the human respiratory system, including the nose and oral cavity, larynx, vocal folds, esophagus, trachea, bronchi, lungs, alveolar sacs, heart, and diaphragm. [Figure 2B] FIG. 2B is a diagram of the human upper respiratory tract, including the nasal cavity, nasal bones, lateral nasal cartilages, greater alar cartilages, nostrils, upper lip, lower lip, larynx, hard palate, soft palate, oropharynx, tongue, epiglottis, vocal folds, esophagus, and trachea. [Figure 2C] Figure 2C is a front view of the face including several features of the surface anatomy, including the upper lip, vermilion, vermilion, lower lip, mouth width, medial canthus, alae of the nose, nasolabial folds, and corners of the mouth. The directions of superior, inferior, radially inward, and radially outward are also noted. [Figure 2D] Figure 2D is a side view of the head including several features of the surface anatomy, including the glabella, serrion, nasal tip, subnasal point, upper lip, lower lip, supramenton, nasal ridge, ala crest, supra- and sub-auricular points. The directions of superior and inferior, anterior and posterior are also indicated. [Figure 2E] Figure 2E is a further lateral view of the head. The approximate locations of the Frankfort horizontal and nasolabial angle are noted. The coronal view is also noted. [Figure 2F] FIG. 2F is a bottom view of the nose including several features including the nasolabial fold, lower lip, vermilion, nostrils, subnasal point, columella, nasal tip, major axis of the nostrils and sagittal plane. [Figure 2G] FIG. 2G is a side view of the surface features of the nose. [Figure 2H] Figure 2H shows the subcutaneous structures of the nose, including the lateral nasal cartilages, nasal septum cartilage, greater alar cartilage, alar cartilage, nasal sesamoid cartilage, nasal bones, epidermis, adipose tissue, frontal process of the maxilla, and fibro-adipose tissue. [Figure 2I] Figure 2I shows the mid-nasal incision, approximately a few millimeters from the sagittal plane, showing in particular the nasal septum cartilage and the medial crus of the greater alar cartilage. [Figure 2J] Figure 2J is a bony frontal view of the skull, including the frontal, nasal, and zygomatic bones. The nasal turbinates are shown along with the maxilla and mandible. [Figure 2K] Figure 2K is a lateral view of the skull along with a profile of the head surface and some muscles. The following bones are shown: frontal, sphenoid, nasal, zygomatic, maxilla, mandible, parietal, temporal, and occipital bones. The mental protuberance is shown. The following muscles are shown: digastric, masseter, sternocleidomastoid, and trapezius. [Figure 2L] Figure 2L shows the anterolateral side of the nose. 3.3 Patient Interface [Figure 3A] FIG. 3A shows a patient interface in the form of a nasal mask in accordance with one form of the present technology. [Figure 3B] Figure 3B is a schematic cross-sectional view of the structure cut at a point, showing the outward normal at this point, and the curvature at this point has a positive sign and a relatively large magnitude compared to the magnitude of the curvature shown in 3C. [Figure 3C] Figure 3C is a schematic cross-sectional view of the structure taken at a point, showing the outward normal at this point. The curvature at this point has a positive sign and a relatively small magnitude compared to the magnitude of the curvature shown in Figure 3B. [Figure 3D] Figure 3D is a schematic cross-sectional view of the structure cut at a point, where the outward normal is shown and the curvature at this point is zero. [Figure 3E] Figure 3E is a schematic cross-sectional view of the structure taken at a point, showing the outward normal at this point. The curvature at this point has a negative sign and a relatively small magnitude compared to the magnitude of the curvature shown in Figure 3F. [Figure 3F]Figure 3F is a schematic cross-sectional view of the structure taken at a point, showing the outward normal at this point. The curvature at this point has a negative sign and a relatively large magnitude compared to the magnitude of the curvature shown in Figure 3E. [Figure 3G] 3G shows a mask cushion including two pillows, the outer surface of the cushion is shown, the edge of the surface is shown, and the dome and saddle regions are shown. [Figure 3H] 3H shows a cushion for a mask. The outer surface of the cushion is shown. The edge of the surface is shown. The path on the surface between points A and B is shown. The linear distance between A and B is shown. Two saddle regions and a dome region are shown. [Figure 3I] Figure 3I shows the surface of a structure with a one-dimensional hole drilled into it. The planar curves shown form the boundary of the one-dimensional hole. [Figure 3J] Figure 3J is a cross-sectional view through the structure of Figure 31. The surfaces shown bound a two-dimensional hole in the structure of Figure 31. [Figure 3K] Figure 3K is a perspective view of the structure of Figure 3I including two-dimensional and one-dimensional holes, and also illustrates the surfaces bounding the two-dimensional holes in the structure of Figure 3I. [Figure 3L] FIG. 3L shows a mask with an inflatable bladder as a cushion. [Figure 3M] Figure 3M is a cross-sectional view of the mask of Figure 3L showing the inner surface of the bladder, which bounds the two-dimensional hole in the mask. [Figure 3N] Figure 3N shows a further cross section through the mask of Figure 3L, the interior surface also being shown. [Figure 3O] Figure 3O illustrates the left-hand rule. [Figure 3P] Figure 3P illustrates the right-hand rule. [Figure 3Q] FIG. 3Q shows the left ear including the left ear helix. [Figure 3R] FIG. 3R shows the right ear including the right ear helix. [Figure 3S] Figure 3S shows a right-handed spiral. [Figure 3T] Figure 3T is a diagram of the mask including the sign of the twist of the space curve defined by the edges of the sealing membrane in different regions of the mask. 3.4 RPT Device [Figure 3U] FIG. 3U shows an RPT device in accordance with one form of the present technology. 3.5 Humidifier [Figure 3V] FIG. 3V is an isometric view of a humidifier in accordance with one form of the present technology. [Figure 3W] 3W is an isometric view of a humidifier in accordance with one form of the present technology, showing the humidifier reservoir 5110 removed from the humidifier reservoir dock 5130. 3.6 Seal-Forming Structures and Patient Interface [Figure 4] FIG. 4 is a perspective view of the seal-forming structure. [Figure 5] FIG. 5 is a perspective view of the seal-forming structure. [Figure 5A] FIG. 5A is a perspective view of a seal-forming structure in which the loop includes a closed end. [Figure 6] FIG. 6 is a plan view of the seal-forming structure. [Figure 7] FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. [Figure 7A] FIG. 7A shows the same cross section as FIG. 7, but with a different angle of structure. [Figure 7B] FIG. 7B shows the mechanical attachment in cross section of FIG. [Figure 7C] FIG. 7C shows the mechanical attachment in cross section of FIG. [Figure 7D] FIG. 7D shows the mechanical attachment in cross section of FIG. [Figure 7E] FIG. 7E shows the mechanical attachment in cross section of FIG. [Figure 7F] FIG. 7F shows the mechanical attachment in cross section of FIG. [Figure 7G] FIG. 7G shows the mechanical attachment in cross section of FIG. [Figure 7H] FIG. 7H shows the mechanical attachment in cross section of FIG. [Figure 7I] FIG. 7I shows the mechanical attachment in the cross-sectional view of FIG. [Figure 8A] FIG. 8A is a cross-sectional view taken along the corresponding line in FIG. [Figure 8B] FIG. 8B is a cross-sectional view taken along the corresponding line in FIG. [Figure 8C] FIG. 8C is a cross-sectional view taken along the corresponding line in FIG. [Figure 8D] FIG. 8D is a cross-sectional view taken along the corresponding line in FIG. [Figure 8E] FIG. 8E is a cross-sectional view taken along the corresponding line in FIG. [Figure 8F] FIG. 8F is a cross-sectional view taken along the corresponding line in FIG. [Figure 8G] FIG. 8G is a cross-sectional view taken along the corresponding line in FIG. [Figure 9] FIG. 9 is a plan view of the seal-forming structure. [Figure 10] FIG. 10 is a perspective view of the seal-forming structure. [Figure 11] FIG. 11 is a simplified diagram of the tubular structure and flaps. [Figure 12] FIG. 12 is a simplified diagram of a tubular structure and flaps attached to a seal-forming structure. [Figure 13] FIG. 13 is a simplified diagram of the compliance of a seal-forming structure. [Figure 14] FIG. 14 is a perspective view of the seal-forming structure. [Figure 15] FIG. 15 is a cross-sectional view showing a rib of the seal-forming structure. [Figure 16] FIG. 16 is a cross-sectional view of a rib under compression. [Figure 17] FIG. 17 is a cross section of a rib under tension. [Figure 18] FIG. 18 is a cross-sectional view of the seal-forming structure. [Figure 19] FIG. 19 is a cross-sectional view of the seal-forming structure. [Figure 20] FIG. 20 shows various regions of the seal-forming structure. [Figure 21]FIG. 21 shows the seal-forming structure attached to the mask shell. [Figure 22] FIG. 22 is an exploded view of the seal-forming structure and two clips. [Figure 23] FIG. 23 shows the cushion and clip. [Figure 23A] FIG. 23A is a cross-sectional view of FIG. 23 taken along line 23A-23A. [Figure 23B] FIG. 23B is a diagram of a seal-forming structure using a foam cushion. [Figure 23C] FIG. 23C is a diagram of the seal-forming structure of FIG. 23B without the foam cushion. [Figure 23D] FIG. 23D is a diagram of a nasal seal forming structure using a foam cushion. [Figure 23E] FIG. 23E is a diagram of the nasal seal-forming structure of FIG. 23D without the foam cushion. [Figure 24] FIG. 24 is a perspective view of the seal-forming structure. [Figure 25A] 25A is a front view of the seal-forming structure of FIG. 24. FIG. [Figure 25B] FIG. 25B shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 25C] FIG. 25C shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 25D] FIG. 25D shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 25E] FIG. 25E shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 25F] FIG. 25F shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 25G] FIG. 25G shows various cross sections taken along corresponding lines in FIG. 25A. [Figure 26] 26 is a rear view of the seal-forming structure of FIG. 24. FIG. [Figure 27] FIG. 27 shows various areas of the seal-forming structure of FIG. [Figure 28A] FIG. 28A is a top perspective view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28B] FIG. 28B is a front view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28C] FIG. 28C is a rear view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28D] FIG. 28D is a top view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28E] FIG. 28E is a bottom view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28F] FIG. 28F is a side view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28G] FIG. 28G is a bottom perspective view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28H] FIG. 28H is another top perspective view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28I] FIG. 281 is another bottom view of a seal-forming structure of a full-face patient interface according to an embodiment of the present technology. [Figure 28J] FIG. 28J is a cross-sectional view of a seal-forming structure of a full-face patient interface taken at line 28J-28J of FIG. 28B according to an embodiment of the present technology. [Figure 28K] FIG. 28K is a cross-sectional view of a seal-forming structure of a full-face patient interface taken at line 28K-28K of FIG. 28B according to an embodiment of the present technology. [Figure 28L] FIG. 28L is a cross-sectional view of a seal-forming structure of a full-face patient interface taken at line 28L-28L of FIG. 28B according to an embodiment of the present technology. [Figure 28M]FIG. 28M is a perspective view of the seal-forming structure of the full-face patient interface shown in FIG. 28L. [Figure 29A] FIG. 29A is a top perspective view of a seal-forming structure and plenum chamber assembly of a full-face patient interface according to an embodiment of the present technology. [Figure 29B] FIG. 29B is a front perspective view of a seal-forming structure and plenum chamber assembly of a full-face patient interface according to an embodiment of the present technology. [Figure 29C] FIG. 29C is a cross-sectional view of a seal-forming structure and plenum chamber assembly of a full-face patient interface taken at line 29C-29C of FIG. 29B according to an embodiment of the present technology. [Figure 29D] FIG. 29D is a cross-sectional view of a seal-forming structure and plenum chamber assembly of a full-face patient interface taken at line 29D-29D of FIG. 29B according to an embodiment of the present technology. [Figure 29E] FIG. 29E is a cross-sectional view of a seal-forming structure and plenum chamber assembly of a full-face patient interface taken at line 29E-29E of FIG. 29B in accordance with an embodiment of the present technology. [Figure 30A] FIG. 30A is a top perspective view of a full-face patient interface according to an embodiment of the present technology. [Figure 30B] FIG. 30B is a top perspective view of a full-face patient interface according to an embodiment of the present technology. [Figure 30C] FIG. 30C illustrates a full face patient interface. [Figure 30D] FIG. 30D illustrates a full face patient interface. [Figure 30E] FIG. 30E illustrates a full face patient interface. [Figure 30F] FIG. 30F shows a cushion assembly. [Figure 30G] FIG. 30G shows a cushion assembly. [Figure 31A] FIG. 31A is a top perspective view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31B] FIG. 31B is a front view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31C] FIG. 31C is a rear view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31D] FIG. 31D is a top view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31E] FIG. 31E is a bottom view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31F] FIG. 31F is a side view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31G] FIG. 31G is a bottom perspective view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31H] FIG. 31H is another top perspective view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31I] FIG. 31I shows another bottom view of a seal-forming structure of a nasal patient interface according to an embodiment of the present technology. [Figure 31J] FIG. 31J is a cross-sectional view of a seal-forming structure of a nasal patient interface taken at line 31J-31J of FIG. 31B according to an embodiment of the present technology. [Figure 31K] FIG. 31K is a cross-sectional view of a seal-forming structure of a nasal patient interface taken at line 31K-31K of FIG. 31B according to an embodiment of the present technology. [Figure 31L] FIG. 31L is a cross-sectional view of a seal-forming structure of a nasal patient interface taken at line 31L-31L of FIG. 31B according to an embodiment of the present technology. [Figure 31M] FIG. 31M is a perspective view of the seal-forming structure of the full-face patient interface shown in FIG. 31L. [Figure 32A]FIG. 32A is a top perspective view of an assembly of a seal-forming structure and plenum chamber of a nasal patient interface according to an embodiment of the present technology. [Figure 32B] FIG. 32B is a front perspective view of a seal-forming structure and plenum chamber assembly of a nasal patient interface according to an embodiment of the present technology. [Figure 32C] FIG. 32C is a cross-sectional view of a seal-forming structure and plenum chamber assembly of a nasal patient interface taken at line 32C-32C of FIG. 32B according to an embodiment of the present technology. [Figure 32D] FIG. 32D is a cross-sectional view of the seal-forming structure and plenum chamber assembly of the nasal patient interface taken at line 32D-32D of FIG. 32B according to an embodiment of the present technology. [Figure 32E] FIG. 32E is a cross-sectional view of a seal-forming structure and plenum chamber assembly of a nasal patient interface taken at line 32E-32E of FIG. 32B according to an embodiment of the present technology. [Figure 32F] FIG. 32F is a cross-sectional view of an assembly of a seal-forming structure and plenum chamber of a nasal patient interface according to an embodiment of the present technology. [Figure 33A] FIG. 33A is a top perspective view of a nasal patient interface according to an embodiment of the present technology. [Figure 33B] FIG. 33B is a top perspective view of a nasal patient interface according to an embodiment of the present technology. [Figure 34A] FIG. 34A is a detailed side view of the seal-forming structure of a related art full-face patient interface to which therapeutic pressure is applied. [Figure 34B] FIG. 34B is a detailed side view of the seal-forming structure of another related art full-face patient interface to which therapeutic pressure is applied. DETAILED DESCRIPTION OF THE INVENTION

[0114] 4 Detailed Description of the Embodiments of the Present Technology Before describing the present technology in further detail, it is to be understood that the present technology is not limited to the specific embodiments described herein, which may vary. It is also to be understood that the terminology used in the present disclosure is for the purpose of describing the specific embodiments described herein, and is not intended to be limiting.

[0115] The following description is provided in connection with various embodiments that may share one or more common characteristics and / or features. It should be understood that one or more features of any one embodiment may be combined with one or more features of another embodiment or other embodiments. In addition, any single feature or combination of features in any of these embodiments may constitute an additional embodiment.

[0116] 4.1 Treatment In one form, the present technology includes a method of treating a respiratory disorder, the method including applying positive pressure to the entrance of the airways of a patient 1000.

[0117] In certain embodiments of the present technology, a supply of air at positive pressure is provided to the patient's nasal passages via one or both nostrils.

[0118] In certain embodiments of the present technology, mouth breathing is restricted, limited or prevented.

[0119] 4.2 Treatment System In one form, the present technology includes an apparatus or device for the treatment of disordered breathing. The apparatus or device may include an RPT device 4000 that supplies pressurized air to the patient 1000 via an air circuit 4170 to a patient interface 3000.

[0120] 4.3 Patient Interface A non-invasive patient interface 3000 in accordance with one aspect of the present technology includes the following functional features: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilizing structure 3300, a vent 3400, a form of connection port 3600 for connection to an air circuit 4170, and a forehead support 3700. In some forms, the functional features may be provided by one or more physical components. In some forms, a single physical component may provide one or more functional features. In use, the seal-forming structure 3100 is positioned to surround the entrance to the patient's airways to facilitate the delivery of air at positive pressure to the airways.

[0121] The inventors have discovered that if the patient interface 3000 cannot comfortably deliver a minimum level of positive pressure to the airway, therapy may be ineffective.

[0122] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to provide an air supply at a positive pressure of at least 6 cmH20 relative to ambient.

[0123] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to provide an air supply at a positive pressure of at least 10 cmH20 relative to ambient.

[0124] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to provide an air supply at a positive pressure of at least 20 cmH20 relative to ambient.

[0125] 4.3.1 Seal formation structure In one form of the present technology, a seal-forming structure 3100 provides a seal-forming surface and may further provide a cushioning function.

[0126] A seal-forming structure 3100 according to the present technology may be constructed from a soft, flexible and resilient material (eg, silicone).

[0127] In one form, the non-invasive patient interface 3000 includes a seal-forming portion that, in use, forms a seal over the upper lip region (ie, upper lip) of the patient's face.

[0128] In one form, the non-invasive patient interface 3000 includes a seal-forming portion that, in use, forms a seal over the chin region of the patient's face.

[0129] In certain forms of the present technology, a system is provided that includes more than one seal-forming structure 3100. Each seal-forming structure 3100 is configured to accommodate a different size and / or shape range. For example, the system may include one form of seal-forming structure 3100 that is suitable for large head sizes but not small head sizes, and another that is suitable for small head sizes but not large head sizes.

[0130] In certain forms of the present technology, the seal-forming structure 3100 is constructed from a biocompatible material (eg, silicone rubber).

[0131] Figure 4 is a perspective view of the seal-forming structure 3100 separated from the rest of the patient interface 3000. The seal-forming structure includes a sealing surface 3105 configured to form a seal around the patient's airway. The seal may be formed around the patient's nose or the patient's nose and oral cavity.

[0132] The seal-forming structure 3100 includes a tether, connector, or loop 3110 that folds the sealing structure 3100 inward (e.g., toward the patient's face in use) about the periphery 3115 of the sealing structure 3100. The periphery 3115 may be generally defined as a wall that supports and / or is formed continuously with the sealing surface 3105. In this manner, the tether 3110 may form a substantially tubular structure 3120 such that the tether 3110 forms a continuous structure (e.g., a continuous circumference) with the sealing surface 3105 and the periphery 3115. Thus, the tether 3110 may include a portion of the sealing surface 3105, a portion of the periphery 3115, and portions that are not part of either the sealing surface 3105 or the periphery 3115. The portion that is not the sealing surface 3105 or the periphery 3115 may take the form of a flap or sheet, attached to or continuous with the sealing surface at one end and attached to or continuous with the periphery 3115 at another end. The tether 3110 may be positioned in line with the patient's nose (e.g., along the alar), above the nasal bone, or anywhere therebetween. Two tethers 3110 may be provided on opposite sides of the patient's nose. The tethers 3110 may be internally open, including at one or both ends, so that the tethers 3110 are internally pressurized (e.g., in fluid communication) by the patient's treatment pressure during use.

[0133] In one form of the present technology, the tether 3110 may extend only partially around the periphery of the seal-forming structure 3100.

[0134] In one form, the tether 3110 and the seal-forming structure 3100 do not form a closed pressurizable structure (e.g., a bladder), such that the space between the tether 3110 and the seal-forming structure 3100 is open to pressure inside the patient interface 3000.

[0135] In one form, the seal-forming structure 3100 has an edge and the tether 3110 holds the edge to prevent rupture at the edge.

[0136] The area of ​​the sealing surface 3105 other than the tether 3110 may include a sealing flap 3125 that projects inwardly toward the inner periphery 3100 of the sealing structure. The sealing flap 3125 may have an unconnected edge at or near a radially inner portion of the sealing surface 3105. The sealing flap 3125 may include a portion 3125a configured to form a seal against the side of the nose above the patient's nasal bone. The sealing flap 3125 may be structured to avoid sealing against the wings (e.g., by being spaced radially outwardly enough from the wings) so that contact with the wings is avoided or minimized.

[0137] Figure 5 is a perspective view of the seal-forming structure 3100 substantially opposite to Figure 4. The substantially tubular structure 3120 may be more readily apparent from this view. Figure 5A shows a tether 3110 with a closed end 3111. This figure also shows the seal-forming structure 3100 without an underlying cushion, and as such the seal-forming structure 3100 may be referred to as a single layer cushion.

[0138] FIG. 6 is a plan view of the seal-forming structure 3100 and serves as the basis for two cross-sectional views shown in FIGS.

[0139] FIG. 7 is a cross-sectional view taken through tether 3110. The substantially tubular structure 3120 can be more easily distinguished from this view. Tether 3110 includes a relatively thick-walled section 3130 and a relatively thin-walled section 3135. The relatively thick-walled section 3130 can be 1 mm to 2 mm thick, or 1.3 mm to 1.7 mm thick, or approximately 1.5 mm thick. The relatively thin-walled section 3135 can be 0.2 mm to 0.8 mm thick, or 0.4 mm to 0.6 mm thick, or approximately 0.5 mm thick. Alternatively, the thickness of the relatively thick-walled section 3130 can be approximately 2.5 to 5 times the thickness of the relatively thin-walled section 3135, or approximately 2.8 to 3.3 times the thickness of the relatively thin-walled section 3135, or approximately 3 times the thickness of the relatively thin-walled section 3135. The relatively thickened section 3130 is shown to comprise the perimeter 3115 and a majority of the sealing surface 3105 in the tether 3110. The relatively thinned section 3135 folds the sealing structure inward and reconnects it to the seal-forming structure 3100 at or near the hinge structure 3140 at a connection point 3165. The hinge structure 3140 is shown as a localized, relatively thin strip or line. This allows the seal-forming structure 3100 to selectively bend or flex in place, thereby providing flexibility to conform to the patient's face. The relatively thickened section 3130 provides sufficient resilience to provide an effective seal against the patient's face. The relatively thinned section 3135 may provide resistance to the sealing surface 3105 from rupturing under pressure while preventing the sealing surface 3105 from becoming too stiff when forming an effective seal. Alternatively, the thicknesses of the relatively thicker and thinner sections 3130, 3135 may be reversed from that shown in Figure 7. Alternatively, the relatively thin section 3135 may extend to encompass the sealing surface 3105. Any combination of thicknesses may be used to achieve the desired combination of sealing ability and burst resistance.

[0140] The connection point 3165 can be determined based on the desired force applied by the tether 3110 or the desired resilience of the tether 3110. For example, as shown in FIG. 7A , the angle 3170 formed by the relatively thin section 3135 can be varied. As the angle 3170 varies, the tension in the relatively thin section 3135 also varies. Thus, the angle 3170 can be optimized for burst resistance and / or patient comfort.

[0141] The angle 3170 can be predetermined in several ways. For example, if the seal-forming structure 3100 is a single molded piece, the angle 3170 is determined by the mold used to form the seal-forming structure 3100. Different angles can be achieved with different molds. Alternatively, the relatively thin section 3135 can be manufactured unconnected, allowing the connection point 3165 to be formed in a subsequent assembly step. The connection point 3165 can be a mechanical connection or an adhesive. If an adhesive is used, the connection point 3165 can vary continuously within an acceptable attachment. Alternatively, a mechanical attachment can be used. FIGS. 7B-7I show an exemplary mechanical attachment. In FIGS. 7B-7E, the connection point 3165 is keyed so that different angles can be achieved at the single connection point 3165. FIGS. 7B and 7C show a first connection orientation of the keyed connection, and FIGS. 7D and 7E show a second connection orientation of the keyed connection. In Figures 7F-7I, multiple separate connection points 3165 are illustrated. The selected connection point 3165 determines the angle 3170. Figures 7F and 7G show a first separate connection of the separate connection points, and Figures 7H and 7I show a second separate connection of the separate connection points. The specific geometries shown in Figures 7B-7I are illustrative only and should not be considered limiting. Other keyed or separate connection geometries may also be used.

[0142] 7, the tethers 3110 can be positioned to contact the side walls of the nose, including the alars. The tethers 3110 can also provide a continuous surface to maintain contact with the sides of the nose above the patient's nasal bone.

[0143] 8A shows a cross-sectional view taken through a vertical plane in FIG. 6. As best seen in FIG. 8, the tether 3110 is attached to the wall forming the perimeter 3115 at attachment site 3145. As shown, the attachment site 3145 is a continuous site of the tether 3110 and may be achieved by molding the seal-forming structure 3100 in one piece. However, the attachment site 3145 may also be achieved in any other convenient manner (e.g., by fastening the free ends of the tether 3110 using some form of mechanical or chemical fastening, such as adhesive). The attachment site 3145, along with the overall length of the tether 3110, may be selected such that sufficient tension is provided to the tether 3110 to counteract rupture of the sealing surface 3105 when pressure (e.g., treatment pressure) acts on the inner surface of the tether 3110 and pulls the seal-forming structure 3100 away from the patient's face and / or when sufficient headgear tension is present.

[0144] Part or all of the sealing surface 3105 may be a (relatively) low friction area. This may be achieved by providing a so-called matte surface. The low friction area may cause the sealing surface to fit less tightly against the patient's face than would be the case without the low friction area. The low friction area may be provided as part of the tether 3110 to allow the sides of the patient's nose to slide freely along the sealing surface 3105 and / or the tether 3110.

[0145] 8A-8G also illustrate various cross sections of FIG. 6, where the intersection of the cross sections indicates that the seal-forming structure 3100 includes various saddles and hemispheres. For simplicity, the intersection of the various cross sections will be referred to herein by a two-letter combination. For example, the intersection of a cross section taken along line 8A-8A and a cross section taken along line 8B-8B will be referred to as intersection AB.

[0146] Intersection AB is taken at a first dome region configured to contact the patient's nasal ridge below the patient's selion. Intersection AC is taken at a first saddle region configured to contact the patient's nasal ridge below intersection AB. Intersection AD is taken at a second saddle region configured to contact the patient's lower lip and / or chin. Intersection EF is taken at a second dome region configured to contact the patient outside and near the patient's oral cavity near the corners of the mouth. Intersection EG is taken at a third saddle region configured to contact the patient's cheek adjacent the patient's ala. Relative to each other, the first dome region has a relatively large curvature along both cross sections, and the second hemisphere region has a relatively small curvature along both cross sections. The first saddle region has a relatively large curvature along both cross sections, and the third saddle region has a relatively small curvature along line 8E-8E and a relatively large curvature along line 8G-8G. The second saddle region has a curvature between the first and third saddle regions along line 8D-8D, as does line 8A-8A along line 8G-8G.

[0147] FIG. 9 illustrates a further embodiment of the present technology. For example, instead of having the tether 3110 continuous with the sealing surface 3105, FIG. 9 illustrates placing the tether 3110 on the underside of the sealing surface 3105. The tether 3110 is illustrated primarily as a dashed line. This configuration may be achieved by attaching or forming a strip or tube of material on the underside of the sealing surface 3105. The underside tether 3110 may be more readily apparent from FIG. 10.

[0148] FIG. 9 also shows a flap 3150. The flap 3150 may extend primarily from the tether 3110 and / or sealing surface 3105 adjacent the patient's nose. Such a flap 3150 may aid in sealing and / or comfort of the patient's nose above the maxilla and adjacent the medial canthus. With some known devices, it may be difficult to seal this area of ​​the patient's face. Alternatively, the flap 3150 may extend from the tether 3110, thereby fixing the position of the flap 3150 relative to the tether 3110. FIG. 11 shows a simplified diagram of the tether 3110 as a substantially tubular structure 3120 with the flap 3150 extending from the interior.

[0149] Figure 12 is a simplified diagram of the substantially tubular structure 3120 shown in Figure 11 attached to the seal-forming structure 3100. According to Figure 12, the substantially tubular structure 3120 can be made separately and fastened to the seal-forming structure 3100.

[0150] 13 shows how the seal-forming structure 3100 can obtain compliance from the substantially tubular structure 3120 so that it can conform to the patient's face. Even when compliant, the technique can prevent rupture.

[0151] Rupture may be understood to refer to deformation of the seal-forming structure 3100, resulting at least in part from a pressure differential when pressure is applied during treatment to displace the sealing surface 3105 from sealing contact with the patient's face. For example, a patient may pull the patient interface 3000 away from their face during treatment (i.e., during pressure application), and as the patient interface 3000 is displaced by the patient from their face, the seal-forming structure 3100 may deform due to the force of the treatment pressure. Then, when the patient reapplies the patient interface 3000 to the patient's face, the sealing surface 3105 of the seal-forming structure 3100 may displace due to deformation, resulting in an ineffective seal and pressurized gas leaking from the seal-forming structure 3100. Upon repositioning the seal-forming structure 3100, internal pressurization of the plenum chamber 3200 may be disrupted, causing a pressure gradient to approach the sealing flap 3125. The pressure gradient may create forces that may ultimately result in the sealing flap rupturing. Displacement of the sealing flaps during rupture can disrupt the seal by causing the sealing flaps to move and creating a leak path when the sealing structure is repositioned on the face. If rupture of the seal-forming structure 3100 occurs near the patient's eye (e.g., displacement of the sealing surface 3105 near the frontal process of the maxilla), pressurized gas can flow toward the patient, which can be particularly disruptive and embarrassing for the patient. Thus, it would be advantageous to be able to reduce rupture.

[0152] Rupture from deformation in the seal-forming structure 3100 can occur outward (e.g., away from the patient's face), and in fact, in extreme conditions of high internal pressure, rupture can cause the seal-forming structure 3100 to double-fold backward.

[0153] The sides of the nose near the frontal process of the maxilla, including the superior nasal bone, and the lateral cartilages can vary greatly depending on the user's profile. Furthermore, to seal this area, the inner edge of the sealing flap 3125 is bent inward (e.g., toward the plenum chamber and perpendicular to the Frankfurt horizontal) and deformed to follow the profile of the sides of the nose. This makes this area particularly susceptible to seal failure leading to rupture. That is, if the sealing flap 3125 is displaced outward (e.g., away from the patient's face) during rupture, it is often difficult to return the sealing flap to a sealing position due to resistance from the pressurized gas force.

[0154] However, rupture can also occur in areas such as the cheeks or upper or lower lip regions where seal disruption is less likely, but which generally have a flatter profile substantially along the coronal plane. During rupture, the sealing flaps may move significantly from the position required for sealing along this plane, and the sealing force imparted by the headgear vector is often sufficient to reposition the sealing flaps to the orientation required to re-establish a seal.

[0155] The rear surface of the sealing flap, which extends from the side of the nose area down to the lower corner of the sealing flap, provides a larger surface area and is therefore more susceptible to displacement under internal pressure.

[0156] A double-walled seal-forming structure 3100 may be more susceptible to rupture, for example, the single-walled seal-forming structure 3100 disclosed in one embodiment of the present technology is particularly susceptible to rupture. It may be appreciated that without an undercushion structure to support the outer sealing wall, the outer sealing wall may be more easily deformed and distorted. Furthermore, the inclusion of an undercushion in a double-walled cushion may assist in repositioning the outer sealing wall against the patient's face during repositioning of the patient interface 3000, which may not be the case in a single-walled cushion.

[0157] Figures 34A and 34B show an example of a related art patient interface 3000 in which a rupture has occurred. In Figure 34A, it can be seen that the seal-forming structure 3100 can be deformed such that the sealing surface 3105 at rupture region BR1 is displaced away from the patient's nose. Furthermore, it can be seen that the seal-forming structure 3100 can be deformed such that the sealing surface 3105 at another rupture region BR2 is displaced away from the side of the patient's nose (e.g., near the frontal process of the maxilla) (see Figure 2H). Similarly, Figure 34B shows the displacement of the sealing surface 3105 of the seal-forming structure 3200 at rupture region BR2 at the side of the patient's nose (e.g., near the frontal process of the maxilla).

[0158] In both of the above-described rupture embodiments, the patient interface 3000 is a full-face patient interface that seals around the nose and oral cavity. Such patient interfaces are particularly susceptible to rupture because the relatively narrow lateral sections in the mid-region are somewhat less supported, and rupture may occur within these regions. Furthermore, the force vectors of the positioning and stabilizing structure 3300 may be oriented generally parallel to the Frankfurt horizontal or sagittal plane. As such, these force vectors may not be directed to impart forces to the seal-forming structure 3100. The seal-forming structure 3100 is oriented generally perpendicularly inward relative to the frontal process of the maxilla, thereby resisting deformation of the seal-forming structure 3100 that would cause rupture. In other words, the treatment pressure forces that cause deformation of the seal-forming structure 3100 may have a magnitude and direction that does not adequately oppose the force vector from the positioning and stabilizing structure 3100. While the rupture phenomenon may be particularly relevant to full-face patient interfaces, it should be understood that nasal patient interfaces are also susceptible to rupture due to the same principles. Thus, the tethers 3110 disclosed herein can be used with nasal and full face patient interfaces to resist bursting.

[0159] Additionally, there is a relevant distinction in the context of the sealing surface 3105. The sealing surface 3105 may be understood to refer broadly to the area on the seal-forming structure 3100 where a seal is intended to occur. Because each patient's head and facial anthropometry varies, the seal-forming structure 3100 may be shaped and sized to provide a comfortable fit and effective seal for a range of patients. Thus, it should be understood that a seal is intended to occur over various areas of the seal-forming structure 3100, and the sealing surface 3105 may refer broadly to such areas. After the seal-forming structure 3100 is actually applied to a particular patient in use, a seal may form at a specific location within the broader area where a seal is intended to occur. The area where a seal actually occurs in use may also be understood as the sealing surface 3105. The specific meaning of the sealing surface 3105 may be understood to be subject to the particular context in which the term is used, as described above.

[0160] Returning to the blowout mentioned above, blowout occurrence may be understood to refer to a situation in which the sealing surface 3105 where the seal is intended to occur is displaced from the patient's face. Such displacement may at the very least prevent an effective seal, or more simply, may prevent sealing contact from occurring altogether.

[0161] FIG. 14 illustrates another embodiment of the present technology that may prevent rupture of the seal-forming structure 3100. Here, two ribs 3155 are shown, but any number of ribs may be provided. For example, a single rib or three or more ribs may be provided. Like the tethers 3110, each rib 3155 tends to prevent rupture of the seal-forming structure 3100 (e.g., the sealing surface 3105). The ribs may be the same thickness or different thicknesses. For example, one or both ribs 3155 may be approximately 1 mm thick, and one or both ribs 3155 may be approximately 0.5 mm thick. Alternatively, the ribs may have variable thicknesses. The sealing surface 3105 may be convex where a rib 3155 is attached and concave where the opposing rib 3155 is attached. Thus, the convex and concave surfaces define the thickness of the material in that region. The ribs 3155 may be provided adjacent the patient's nose.

[0162] FIG. 15 shows a cross section of the seal-forming structure 3100 taken perpendicular to the plane of the ribs 3155. The ribs 3155 can be relatively compliant when compressed or can easily collapse under sealing loads, allowing the seal-forming structure 3100 and / or sealing surface 3105 to conform to the patient's face. This is shown in FIG. 16. However, as shown in FIG. 17, the ribs 3155 can provide a relatively high resistance to tension that may develop when the inside of the seal-forming structure 3100 (e.g., the surface 3105a opposite the sealing surface 3105) is pressurized. In this manner, the ribs 3155 can tend to resist rupture of the seal-forming structure 3100 (e.g., the ribs 3155 can be tension members). For example, the ribs 3155 tend to hold the seal-forming structure 3100 in an "as-formed" state or in a shape under rupture conditions.

[0163] The extension flap 3160 shown in Figures 18 and 19 may allow the distance D1 vs. D2 to be increased to accommodate facial variations when the distance between the sides of the nose and the sealing flap changes. The sealing surface 3105 of the extension flap 3160 may also provide an effective seal against the cheek. The arrows indicate areas of potential patient contact. This type of structure primarily seals with the membrane on traditional silicone masks, which are prone to rupture when readjusting the mask position. The tethers 3110 or ribs 3155 may prevent rupture from occurring while allowing for distance variations due to facial differences to effectively seal.

[0164] 20 shows a view similar to FIG. 6, except that patterns are included on the seal-forming structure 3100. These patterns indicate regions 3175 of similar thickness in the seal-forming structure 3100.

[0165] Region 3175A can be a relatively thin region (e.g., about 0.3 mm), which can be made thin and compliant for comfort on the bridge of the nose.

[0166] Region 3175B can be a very thin region (e.g., about 0.2 mm). By reducing the thickness relative to region 3175A, tension can be significantly reduced, which can result in minimal facial marking at the bridge of the nose, which is a bony area in most patients and therefore prone to marking and / or discomfort.

[0167] Region 3175C can be a semi-thin region (e.g., about 1 mm) This region can be semi-thin to prevent pinching on the sides of the nose.

[0168] Region 3175D can be a semi-thick region (e.g., about 1.5 mm). This region can seal against the cheeks along the nose. This area on the face typically has more fat than the sides of the nose or bridge, allowing a relatively large sealing force to be applied without discomfort. The semi-thick region can also provide more structural rigidity than thinner regions.

[0169] Region 3175E may be a thicker region (e.g., approximately 2.0 mm). This thicker peripheral region may provide a stiffer outer wall to support the inner portion of the cushion. Region 3175E may function like the undercushion of a conventional dual-layer cushion design; for example, region 3175E may support the portions of the seal-forming structure 3100 that contact the patient's face. For example, region 3175E may provide support to regions 3175D and / or 3175F (described below). The overall cross-sectional shape of the cushion may be curved to provide an air (pressure) assisted spring for sealing and compliance. In this configuration, the disclosed configurations including such a thicker region may be advantageous over prior thick undercushions of conventional masks because they may also be compressible to provide a level of compliance to assist in seal formation. As a result, it may be possible to increase the overall range of distances over which the cushion can be compressed compared to conventional dual-layer designs.

[0170] Region 3175F can be a thin-walled region (e.g., about 0.3-0.5 mm). The portion that seals under the lower lip can be thin (e.g., about 0.3 mm) to allow for jaw movement. Such a thin-walled membrane region can also reduce stress on the patient's gums for comfort. This portion of region 3175F adjacent region 3175D is where the tether 3110 is placed. This portion of region 3175F is thin (e.g., about 0.5 mm) to allow for compression of the tether 3110. The portion of region 3175F configured to contact the side of the patient's mouth can be about 0.5 mm and acts like the sealing membrane layer of a dual-layer cushion, maintaining a seal with subtle changes in facial profile and movement during sleep.

[0171] Although distinct lines are shown between regions 3175, the boundaries between the regions are approximations, as there may be smooth transitions in relative thickness between the regions. This may be advantageous because it may improve aesthetics, as it limits the naked eye's ability to distinguish between thick and thin regions. However, distinct transitions may also be provided.

[0172] WO 2006 / 074513 discloses a cushion, the entire contents of which are incorporated herein by reference. In such a cushion, a thicker undercushion and a thicker membrane layer are disclosed. The thicker membrane relieves (i.e., expands) the seal on the face under pressure, and the undercushion provides support to support the seal. The curved cross-section provides a pressure-assist spring to support the seal under headgear tension.

[0173] In contrast, a seal-forming structure 3100 including one or more of the above-described regions 3175 may have only a single layer. This single layer may combine the functions of the membrane and undercushion of WO 2006 / 074513. The maximum cross-sectional thickness of region 3175 (e.g., region 3175E) may be thinner than the maximum thickness of the undercushion of WO 2006 / 074513. However, the combined undercushion and membrane in a single layer provides sufficient structural rigidity to maintain the cushion shape and supportive sealing action. Furthermore, the reduced maximum thickness allows a single layer of the seal-forming structure 3100 to compress over a greater distance than a conventional dual-layer design, thereby increasing compliance before bottoming out.

[0174] In a mask provided in the system disclosed in WO 2014 / 117227, a foam cushion is supported by a flexible clip attached to a second, rigid clip, each of which is incorporated herein by reference in its entirety. A similar system, disclosed in FIG. 21, employs two ribs 3155, configured to be located on opposite sides of the patient's nose. Only one rib is shown in FIG. 21. These ribs function as tethers to prevent rupture of the flexible clip and attached foam seal. While ribs 3155 are shown, tethers 3110 may be used instead.

[0175] Thus, in another embodiment of the present technology, the seal-forming structure 3100 includes a cushion 3810, which may be constructed of foam. The cushion defines a single area that covers the patient's nose in the case of a nasal mask, or the nose and oral cavity in the case of a full-face mask. The foam cushion may be constructed of, for example, any suitable material (e.g., one or more of polyethylene, polyurethane, and ethylene vinyl acetate (EVA)). In some cases, the foam cushion may be a semi-closed cell foam (e.g., made of polyurethane). Semi-open cell foam cushions may have limited permeability (e.g., to the extent described in more detail in WO2014 / 117227). The permeability disclosed therein is incorporated herein by reference.

[0176] The cushion 3810 may have a substantially triangular or pear-shaped shape, with a sealing surface that conforms to the contours of the user's face. The foam cushion is designed to attach to a first support (e.g., flexible) clip 3812, which itself is attached to a second, more rigid clip 3814 (as shown in FIG. 22 ) or directly to the mask shell 3816. In one embodiment, the first support clip 3812 may be a flexible clip that is more rigid than the foam cushion and more flexible than the second clip 3814. It is the combination of the foam and the flexible clip that defines the physical characteristics of the overall sealing interface. The flexible clip allows the interface to accommodate large variations and better conform to the contours of the patient's face. The compliant nature of the foam cushion allows for fine adjustments and creates a comfortable interface layer that interacts with the patient's skin.

[0177] The first support clip 3812 may be prone to rupture due to its flexibility and compliance. Another aspect of the present technology, shown in FIG. 21 , may prevent rupture of the first support clip 3812 and attached cushion 3810. Here, the illustrated configuration includes two ribs 3155 (only one of which is shown due to symmetry and orientation of the drawing), but any number of ribs may be provided. For example, a single rib or three or more ribs may be provided. Similar to the tethers 3110, each rib 3155 acts as a tension member, thereby tending to prevent rupture of the first support clip 3812 and attached cushion 3810. The ribs may be the same thickness or different thicknesses. For example, one or both ribs 3155 may be approximately 1 mm thick and one or both ribs 3155 may be approximately 0.5 mm thick. Alternatively, the ribs may have variable thicknesses. The ribs 3155 may be provided adjacent the patient's nose.

[0178] 21 shows a side view of the cushion assembly 3800. The cushion assembly 3800 includes a seal-forming structure 3100. The seal-forming structure 3100 includes a mask shell 3816, a permanently attached flexible first support clip 3812, and a foam cushion 3810. As shown, the flexible first support clip may be secured to the mask shell 3816 via a pair of ribs 3155 that act as tethers to prevent rupture. These ribs 3155 may be relatively compliant when compressed or may easily collapse under sealing loads, allowing the seal-forming structure 3100 to conform to the patient's face. Adjustment of the tension provided by the ribs 3155 may be achieved by changing any one or more of their material composition, geometry, or position.

[0179] Figure 23 shows the foam cushion 3810 and flexible first support clip 3812, with the patient contact surface visible. Figure 23A is a cross section along a vertical plane of symmetry taken through Figure 23, showing the foam cushion, flexible first support clip 3812 and ribs 3155.

[0180] 23, a sagittal plane 3818 is also shown, which bisects the seal-forming structure 3100 into left and right halves. The sagittal plane 3818 may include a line 3820. The line 3820 may have contact points with the foam cushion 3810 at only two contact points: a first contact point (upper contact point) 3825 at an upper portion of the foam cushion 3810 and a second contact point (lower contact point) 3830 at a lower portion of the foam cushion 3810.

[0181] In another example of the present technology, the seal-forming structure 3100 may include a pair of tethers 3110 to prevent rupture of the first support clip 3812. Each tether 3110 is formed by an inward bending of the circumferential flexible support clip 3812, thereby forming a connection point 3165. In this manner, the tethers 3110 may form a substantially tubular structure 3120. The tethers form a tether that is resistant to rupture from internal pressurization of the plenum chamber. The tension provided by the ribs 3155 may be adjusted by altering any one or more of its material composition, the geometry or location of the connection points 3165 of the tethers 3110.

[0182] In another example of the present technology, the foam cushion 3810 may be secured (removably or permanently) to the mask shell 3816 by a flexible support structure 3835. The configuration shown in Figures 23B-23D may allow for variable stiffness to increase comfort for the patient. Variable stiffness may be achieved in a variety of ways.

[0183] The compressibility of the seal-forming structure 3100 may be highest in the nose bridge region 3840. The nose bridge region 3840 may be a location where the patient's nose may engage the foam cushion 3810. The nose bridge region 3840 may also be the region that includes the first contact point 3825. It is contemplated that the foam cushion 3810 may be saddle-shaped in at least a portion of the nose bridge region 3840.

[0184] The compressibility of the seal-forming structure 3100 may be lower in the chin region 3845. The chin region 3845 may be where the patient's nose may engage the foam cushion 3810. The chin region may also be the region that includes the second contact point 3830.

[0185] The compressibility of the seal-forming structure 3100 may be lowest in an intermediate region 3850 between the nose region 3840 and the chin region 3845. The intermediate region 3850 may be configured to engage the patient's cheeks and the sides of the patient's mouth.

[0186] As shown in FIG. 23B, the depth d of the support structure 3835 may be greater in the nose bridge region 3840. The depth d may be smaller in the chin region 3845. Additionally, the depth d may be smallest in the middle region 3850. The depth d of the support region

[0187] The depth d of the support structure 3835 may be related to the compressibility of the seal-forming structure 3100. The elastomeric wall thickness of the support structure 3835 may also be related to the compressibility of the seal-forming structure 3100. As such, the elastomeric thickness of the support structure 3835 may be different at different locations on the seal-forming structure 3100. For example, the support structure 3835 may be thinnest in the nose bridge region 3840 and thickest in the mid region 3850. Additionally, the ribs 3155 may also affect the compressibility. As such, the ribs 3155 may be placed in locations where a lower compressibility is desired.

[0188] It should be appreciated that the compressibility of the seal-forming structure 3100 can be affected by material selection, for example, different silicone materials with different flexibility will have different compressibility characteristics.

[0189] The support structure 3835 may be attached to the foam cushion at a fold section 3855. The width w of the fold section 3855 may vary at different locations on the seal-forming structure 3100 to provide varying support for the foam cushion 3810. In most cases, the fold section 3855 is designed to allow the foam cushion 3810 to overhang to different degrees. Allowing the foam cushion 3810 to overhang at the fold section 3855 facilitates rotation of the foam cushion 3810 and helps it resist "popping out." However, too much inward rotation due to overhang may cause discomfort due to contact with the supporting silicone structure and may increase load on the patient's face. Therefore, overhang may be relatively small in areas prone to discomfort, such as the nose bridge region 3840 and chin region 3845.

[0190] Additionally, the angle α formed by the two legs formed by the bend in the support structure 3835 may be different in different regions of the seal-forming structure 3100. Such different angles allow the foam cushion 3810 to follow the contours of the patient's face.

[0191] Figures 24-27 show a seal-forming structure 6000 which is similar to the seal-forming structure 3100 except as described hereinabove. Like reference numerals are the same as those described above for the seal-forming structure 3100 and will not be described in further detail. The seal-forming structure 6000 shown in Figures 24-27 may have features that make it primarily suitable for use with a nasal mask.

[0192] 25B-25G also show various cross sections of FIG. 25A, where the intersections of the cross sections indicate that the seal-forming structure 6000 includes various saddles and hemispheres. For simplicity, the intersections of the various cross sections will be referred to herein by a two-letter combination. For example, the intersection of the cross section taken along line 25B-25B and the cross section taken along line 25C-25C will be referred to as intersection BC.

[0193] Intersection BC is taken at a first saddle region configured to contact the patient's nasal ridge below the patient's septum. Along line 25B-25B, the curvature is relatively small, and along line 25C-25C, the curvature is relatively large. The curvature along line 25B-25B is large enough so that the first saddle region approximates a cylindrical region. If desired, the first saddle region may be cylindrical. Intersection BD is taken at a second saddle region configured to contact the patient's upper lip. Along line 25B-25B, the curvature is relatively small compared to along line 25D-25D. Intersection CF is taken at a first dome region configured to contact the patient's nose adjacent the nasal ridge. Along lines 25F-25F and 25C-25C, the curvature is relatively similar. Intersection FG is taken at a third saddle region formed by tether 3110 configured to contact the patient's nose alongside. The curvature along line 25F-25F is relatively small, approaching zero curvature. The curvature along line 25G-25G is relatively large compared to line 25F-25F. As such, the third saddle region approximates a cylindrical region and may be made cylindrical if desired. Intersection EF is taken at a second dome region configured to contact the patient alongside the patient's ala of the nose. The curvatures along lines 22E-22D and 22F-22F are relatively similar.

[0194] 27 shows a seal-forming structure 6000, except that patterns are included on the seal-forming structure 6000. These patterns designate regions 6005 of similar properties and / or thickness as the seal-forming structure 6000.

[0195] The region 6005A, referred to herein as the nose region, may be approximately 0.5 mm thick, thereby preventing wrinkles and / or creases of the seal-forming structure 6000 in this region.

[0196] Region 6005B, referred to herein as the base region, may be approximately 2.9 mm to 3.45 mm thick. For example, the thickness may be 2.9 mm in 6005B2, 3.0 mm in 6005B1 and 6005B3, and 3.45 mm in 6005B4. Region 6005B may provide support or a base for the sealing flap 3125 and may provide and maintain the overall shape of the seal-forming structure 6000.

[0197] Region 6005C, referred to herein as the undercushion zone, may be 0.95 mm to 2.1 mm thick. As shown, this region may be the majority of the cushion. For example, region 6005C may be approximately 50% of the cushion. The thickness of the upper portion of region 6005C1 may be 0.95 mm to 1.6 mm, and the thickness of the lower portion of region 6005C2 may be 1.25 mm to 2.1 mm. The thickness may vary continuously between these values ​​to provide a smooth appearance.

[0198] Region 6005D, referred to herein as the membrane region, may form approximately one-third of the seal-forming structure 6000 and may include the tether 3110. It may be approximately 0.35 mm thick. This region may be relatively thin so that it can function as a biased (e.g., pressure-activated) seal against the patient's face. The sides 6005D1 may be substantially parallel to the patient's face, reducing the likelihood of puckers and resulting leakage. Such puckers are more likely to occur in dynamic situations (e.g., when the seal is in motion).

[0199] Region 6005F, referred to herein as the spring zone, may have a thickness of 1.1 mm to 1.8 mm. This zone may act as a spring, allowing compression on the upper lip to reduce pressure on the upper lip. This region may gradually increase in stiffness from the center of the upper lip (where the stiffness of 6005F is highest from the center of the region) to the corners of the nose (e.g., the alar crest).

[0200] Region 6005G may be referred to herein as the nasal recess region and may be deeper to better accommodate patients with higher nasal bridges and / or to provide a more comfortable seal. This region may have a similar thickness to region 6005D (e.g., about 0.35 mm) and may therefore be a sub-region of region 6005D.

[0201] The terms "soft" and "flexible," and their derivatives, when used herein to describe the first support clip 3812, are intended to have the meaning of the term "elastic," as specifically defined in the "Terminology Used in Connection with Patient Interface" section. That is, a flexible support clip is substantially elastically deformable and can release all of its energy substantially quickly upon unloading.

[0202] The seal-forming structure 3100 may be advantageous in one or more aspects of the present technology. For example, human facial structure may vary from person to person, presenting challenges when designing a seal for use with a large number of different faces. These differences include different shapes of facial structure (e.g., differently shaped noses and / or differently curved cheeks) and / or different tissue content (e.g., more or less adipose tissue). Due to these differences, a conventional seal-forming structure may work well for one person and not for another. Additionally, perceived comfort may vary from person to person, independent of facial structure. Using the seal-forming structure 3100 described herein, a greater proportion of users may be able to effectively use the seal-forming structure 3100 (e.g., a greater proportion of users may have the seal-forming structure 3100 to form an effective seal and / or a greater proportion of users may perceive the seal-forming structure 3100 as comfortable) compared to conventional seal-forming structures.

[0203] 28A-28M illustrate an exemplary full-face seal-forming structure 3100 including a tether 3110. As can be seen in FIG. 28K, for example, the tether 3110 can extend between a first inner surface region 3180 and a second inner surface region 3185. The first inner surface region 3180 can be understood to be on the opposite side of the sealing face 3105 of the seal-forming structure. The second inner surface region 3185 can be understood to be elsewhere. In the embodiment shown in FIG. 28K, the second inner surface region 3185 is disposed on the interior of the seal-forming structure 3100. In other embodiments, the second inner surface region 3185 can be disposed on the interior of the plenum chamber 3200 such that the tether 3110 extends between the seal-forming structure 3100 and the plenum chamber 3200. The location of the second inner surface region 3185 can be selected based on the desired directional component of the tension vector of the tether 3100 to withstand the burst force.

[0204] 28L and 28M are detailed cross-sectional views, particularly showing the connection point 3165 where the tether 3110 extends from the second inner surface region 3165. The connection point 3165 in this embodiment may be curved to reduce stress concentrations in this area, thereby reducing the tendency of the tether 3110 to fracture. Additionally, the tether 3110 may extend from the second inner surface region 3185 a distance from the bond region 3190 where the seal-forming structure 3100 is bonded to the plenum chamber 3200 during manufacturing. This may prevent damage to the tether 3110 when bonding the seal-forming structure 3100 to the plenum chamber 3200. FIGS. 29C-29E also show how the tether 3110 extends from the second inner surface region 3185 a distance from the bond region 3190 and the plenum chamber 3200.

[0205] The cross-sectional views of Figures 28J-28L also illustrate how the tether 3110 can extend from the first interior surface region 3180. As can be seen in these examples, the tether 3110 extends from the first interior surface region 3110 at a location adjacent to, but not at, the closure flap 3125. However, in other examples, the tether 3110 can extend from the first interior surface region 3180 closer to or at the edge of the closure flap 3125.

[0206] 30A and 30B show an example of a full face patient interface 3000 that includes a seal-forming structure 3100 incorporating features of the present technology and does not include the positioning and stabilizing structure 3300 described.

[0207] 31A-31M show another example of the present technology, which is a nasal seal-forming structure 3100. As can be seen in Fig. 31K, for example, the tether 3110 extends proximate to the sealing flap 3125. As such, there may not be a defined edge in this area. Furthermore, it should be understood that at least a portion of the tether 3110 in such an arrangement may form part of the sealing surface 3105 in use depending on the anthropometry of the patient's face.

[0208] 32C-32E illustrate that in an embodiment of the nasal patient interface 3000, the tether 3110 may extend from the second inner surface region 3185 at a further distance from the bond region 3190 compared to the full face patient interface 3000. FIG.

[0209] 4.3.2 Plenum chamber The plenum chamber 3200 has edges shaped to complement the surface contours of an average human face in the area where a seal is formed in use. In use, the peripheral edges of the plenum chamber 3200 are positioned in close proximity to the adjacent surfaces of the face. Actual contact with the face is provided by the seal-forming structure 3100. The seal-forming structure 3100 may extend around the entire edge of the plenum chamber 3200 in use.

[0210] In certain forms of the present technology, the plenum chamber 3200 is constructed from a transparent material (e.g., clear polycarbonate). The use of a transparent material may reduce the intrusiveness of the patient interface and may help improve compliance with treatment. The use of a transparent material may help the clinician see the placement and function of the patient interface.

[0211] In certain forms of the present technology, the plenum chamber 3200 is constructed from a translucent material, which can make the patient interface less intrusive and help improve compliance with treatment.

[0212] 4.3.3 Positioning and stabilizing structures The seal-forming structure 3100 of the patient interface 3000 of the present technology may be held in a sealed position by the positioning and stabilising structure 3300 in use.

[0213] In one form, the positioning and stabilizing structure 3300 provides at least enough holding force to overcome the effect of the positive pressure in the plenum chamber 3200 to lift off the face.

[0214] In one form, the positioning and stabilizing structure 3300 provides a holding force sufficient to overcome the attractive force on the patient interface 3000.

[0215] In one form, the positioning and stabilizing structure 3300 provides a holding force as a safety margin to eliminate the possibility of destructive action on the patient interface 3000 (e.g., due to tube drag or inadvertent interference with the patient interface).

[0216] In one form of the present technology, there is provided a positioning and stabilizing structure 3300 configured to be worn by a patient while sleeping. In one example, the positioning and stabilizing structure 3300 has a low profile or cross-sectional thickness to reduce the perceived or actual bulk of the device. In one example, the positioning and stabilizing structure 3300 includes at least one strap having a rectangular cross-section. In one example, the positioning and stabilizing structure 3300 includes at least one flat strap.

[0217] In one form of the present technology, a positioning and stabilizing structure 3300 is provided that is configured so that it is not excessively large or bulky in size that would interfere with a patient sleeping in a supine sleeping position with the posterior region of the patient's head resting on a pillow.

[0218] In one form of the present technology, a positioning and stabilizing structure 3300 is provided that is configured so that it is not excessively large or bulky in size that would interfere with a patient sleeping in a lateral sleeping position with the side region of the patient's head resting on a pillow.

[0219] In one form of the present technology, the positioning and stabilizing structure 3300 includes a strap constructed from a laminate of a fabric patient-contacting layer, a foam material inner layer, and a fabric outer layer. In one form, the foam material is porous to allow moisture (e.g., sweat) to pass through the strap. In one form, the fabric outer layer includes a tie material that engages with a hook material portion.

[0220] In certain forms of the present technology, the positioning and stabilizing structure 3300 includes stretchable (e.g., stretchable with elasticity) straps. For example, the straps can be configured to be tensioned in use to direct a force that seals the cushion against a portion of the patient's face. In one example, the straps can be configured as ties.

[0221] In certain forms of the present technology, the positioning and stabilizing structure 3300 includes straps that are bendable, e.g., non-rigid. An advantage of this embodiment is that the straps are more comfortable when the patient lies down to sleep.

[0222] In a particular form of the present technology, the positioning and stabilizing structure 3300 includes straps configured to be breathable to allow water vapor to pass therethrough.

[0223] In certain forms of the present technology, a system is provided that includes more than one positioning and stabilizing structure 3300. Each positioning and stabilizing structure 3300 is configured to provide a holding force to accommodate a range of different sizes and / or shapes. For example, the system may include one form of positioning and stabilizing structure 3300 that is suitable for large sized heads but not for small sized heads, and another form of positioning and stabilizing structure 3300 that is suitable for small sized heads but not for large sized heads.

[0224] 4.3.4 Ventilation In one form, the patient interface 3000 includes a vent 3400 constructed and arranged to allow the expulsion of exhaled gases (eg, carbon dioxide).

[0225] The vent 3400 in one form according to the present technology includes a plurality of holes (eg, about 20 to about 80 holes, or about 40 to about 60 holes, or about 45 to about 55 holes).

[0226] The vent 3400 may be located within the plenum chamber 3200. Alternatively, the vent 3400 is located within a decoupling structure (e.g., a swivel).

[0227] 4.3.5 Decoupling Structures In one form, the patient interface 3000 includes at least one decoupling structure (eg, a swivel or a ball socket).

[0228] 4.3.6 Connection Port The connection port 3600 allows connection to the air circuit 4170 .

[0229] 4.3.7 Forehead support In one form, the patient interface 3000 includes a forehead support 3700 .

[0230] 4.3.8 Anti-asphyxiation valve In one form, the patient interface 3000 includes an anti-asphyxiation valve.

[0231] 4.3.9 Ports In one form of the present technology, the patient interface 3000 includes one or more ports that allow access to the volume within the plenum chamber 3200. In one form, this allows a clinician to provide supplemental oxygen. In one form, this allows a property of the gas (e.g., pressure) within the plenum chamber 3200 to be directly measured.

[0232] 4.4 RPT Device An RPT device 4000 according to one aspect of the present technology includes mechanical, pneumatic, and / or electrical components and is configured to execute one or more algorithms 4300. The RPT device 4000 can be configured to generate an airflow that is delivered to a patient's airway for treatment of one or more of the respiratory conditions, for example, as described anywhere herein.

[0233] The RPT device may have an outer housing 4010 formed as two parts: an upper portion 4012 and a lower portion 4014. Further, the outer housing 4010 may include one or more panel(s) 4015. The RPT device 4000 includes a chassis 4016 that supports one or more internal components of the RPT device 4000. The RPT device 4000 may include a handle 4018.

[0234] The air pressure path of the pneumatic RPT device 4000 may include one or more air circuit items (e.g., an inlet air filter 4112, an inlet muffler 4122, a pressure generator 4140 (e.g., a blower 4142) capable of supplying air at positive pressure, an outlet muffler 4124) and one or more transducers 4270 (e.g., a pressure sensor 4272 and a flow sensor 4274).

[0235] One or more of the pneumatic circuit items may be disposed within a removable, unitary structure referred to herein as a pneumatic block 4020. The pneumatic block 4020 may be disposed within the outer housing 4010. In one form, the pneumatic block 4020 is supported by or formed as part of the chassis 4016.

[0236] The RPT device 4000 can have a power supply 4210, one or more input devices 4220, a central controller 4230, a therapy device controller 4240, a pressure generator 4140, one or more protection circuits 4250, a memory 4260, a transducer 4270, a data communication interface 4280, and one or more output devices 4290. The electrical components 4200 can be mounted on a single printed circuit board assembly (PCBA) 4202. In an alternative, the RPT device 4000 can include more than one PCBA 4202.

[0237] 4.4.1 RPT Device Mechanical and Pneumatic Components The RPT device may include one or more of the following components in an integral unit: In an alternative, one or more of the following components may be arranged as their own separate units.

[0238] 4.4.1.1 Air filters An RPT device in accordance with one form of the present technology may include an air filter 4110 or multiple air filters 4110.

[0239] In one form, the inlet air filter 4112 is located at the beginning of the air pressure path upstream of the pressure generator 4140 .

[0240] In one form, an outlet air filter 4114 (eg, an antibacterial agent) is located between the outlet of the pneumatic block 4020 and the patient interface 3000.

[0241] 4.4.1.2 Mufflers An RPT device in accordance with one form of the present technology may include a muffler 4120 or multiple mufflers 4120.

[0242] In one form of the present technology, an inlet muffler 4122 is positioned above a pressure generator 4140 in the pneumatic path.

[0243] In one form of the present technology, the outlet muffler 4124 is positioned in the pneumatic path between the pressure generator 4140 and the patient interface 3000.

[0244] 4.4.1.3 Pressure generator In one form of the present technology, the pressure generator 4140 that generates the air flow or supply at positive pressure is a controllable blower 4142. For example, the blower 4142 may include a brushless DC motor 4144 with one or more impellers housed within a volute. The blower may deliver the air supply at a rate of, for example, up to about 120 liters / minute, at a positive pressure ranging from about 4 cmH2O to about 20 cmH2O, or in other forms up to about 30 cmH2O. The blower may be described in any one of the following patents or patent applications, which are incorporated herein by reference in their entirety: U.S. Patent No. 7,866,944; U.S. Patent No. 8,638,014; U.S. Patent No. 8,636,479; and WO 2013 / 020167.

[0245] The pressure generator 4140 is under the control of the therapy device controller 4240 .

[0246] In other forms, pressure generator 4140 can be a piston-driven pump, a pressure regulator connected to a high pressure source (eg, a compressed air reservoir), or a bellows.

[0247] 4.4.1.4 Converters The transducer may be internal to the RPT device or external to the RPT device. An external transducer may, for example, be located on the air circuit or form part of the air circuit (e.g., a patient interface). An external transducer may take the form of a non-contact sensor (e.g., a Doppler radar motion sensor that transmits or moves data to the RPT device).

[0248] 4.4.2 RPT Device Electrical Components 4.4.2.1 Power supply The power supply 4210 may be located inside or outside the external housing 4010 of the RPT device 4000.

[0249] In one form of the present technology, the power supply 4210 powers only the RPT device 4000. In another form of the present technology, power is provided from the power supply 4210 to both the RPT device 4000 and the humidifier 5000.

[0250] 4.4.2.2 Input Devices In one form of the present technology, the RPT device 4000 includes one or more input devices 4220 in the form of buttons, switches, or dials to allow a human to interact with the device. The buttons, switches, or dials may be physical or software devices accessible via a touchscreen. The buttons, switches, or dials may be physically connected to the external housing 4010 in one form, or may communicate wirelessly with a receiver electrically connected to a central controller in another form.

[0251] 4.4.2.3 Optional displays and output devices, including alarms Output devices according to the present technology may take the form of one or more of visual, audio and tactile units. Visual displays may be liquid crystal displays (LCD) or light emitting diode (LED) displays.

[0252] 4.5 Air Circuit An air circuit 4170, according to one aspect of the present technology, is a conduit or tube constructed and arranged such that, in use, air flow travels between two components (e.g., the RPT device 4000 and the patient interface 3000).

[0253] In particular, the air circuit 4170 may be fluidly connected to the outlet of the pneumatic block 4020 and the patient interface. The air circuit may be referred to as an air delivery tube. In some cases, there may be separate limbs of the circuit for inhalation and exhalation. In other cases, a single limb is used.

[0254] In some forms, the air circuit 4170 may include one or more heating elements configured to heat the air in the air circuit (e.g., to maintain or increase the air temperature). The heating elements may take the form of a heated wire circuit and may include one or more transducers (e.g., temperature sensors). In one form, the heated wire circuit may be spirally wound around the axis of the air circuit 4170. The heating elements may be in communication with a controller (e.g., a central controller). One example of an air circuit 4170 including a heated wire circuit is described in U.S. Patent Application No. 8,733,349, the entire contents of which are incorporated herein by reference.

[0255] 4.6 Humidifier 4.6.1 Humidifier Overview In one form of the present technology, a humidifier 5000 is provided (for example as shown in FIGS. 3V and 3W) for changing the absolute humidity of air or gas to be delivered to a patient relative to ambient air. Typically, the humidifier 5000 is used to increase the absolute humidity (relative to ambient air) and increase the temperature of the air stream before delivery to the patient's airways.

[0256] The humidifier 5000 may include a humidifier reservoir 5110, a humidifier inlet 5002 for receiving an airflow, and a humidifier outlet 5004 for delivering a humidified airflow. In some forms, such as shown in Figures 3V and 3W, the inlet and outlet of the humidifier reservoir 5110 may be the humidifier inlet 5002 and the humidifier outlet 5004, respectively. The humidifier 5000 may further include a humidifier base 5006. The humidifier base 5006 may be adapted to receive the humidifier reservoir 5110 and may include a heating element 5240.

[0257] 4.6.2 Humidifier Components 4.6.2.1 Water reservoir According to one arrangement, the humidifier 5000 may include a water reservoir 5110 configured to contain or hold a quantity of liquid (e.g., water) to be evaporated for humidifying the air stream. The water reservoir 5110 may be configured to contain a predetermined maximum quantity of water to provide adequate humidification for at least the duration of a respiratory therapy session (e.g., a night's sleep). Typically, the reservoir 5110 is configured to contain several hundred milliliters of water (e.g., 300 milliliters (ml), 325 ml, 350 ml, or 400 ml). In another form, the humidifier 5000 may be configured to receive a water supply from an external water source (e.g., a building's water supply system).

[0258] According to one embodiment, the water reservoir 5110 is configured to humidify the air flow from the RPT device 4000 as the air flow passes through the RPT device 4000. In one form, the water reservoir 5110 can be configured to encourage the air flow to travel a tortuous path through the reservoir 5110 while the air flow contacts a certain amount of water in the reservoir 5110.

[0259] According to one form, the reservoir 5110 may be laterally removable from the humidifier 5000, for example as shown in Figures 3V and 3W.

[0260] The reservoir 5110 may also be configured to inhibit liquid release from the reservoir 5110, for example, when the reservoir 5110 is displaced and / or rotated from its normal operating orientation (e.g., through any aperture and / or between its subcomponents). Because the air flow to be humidified by the humidifier 5000 is often pressurized, the reservoir 5110 may also be configured to avoid loss of air pressure through leakage and / or flow impedance.

[0261] 4.6.2.2 Conductive parts According to one arrangement, the reservoir 5110 includes a conductive region 5120 configured to allow efficient heat transfer from the heating element 5240 to the volume of liquid in the reservoir 5110. In one form, the conductive region 5120 may be arranged as a plate, although other shapes may be suitable. All or part of the conductive region 5120 may be constructed of a thermally conductive material such as aluminum (e.g., approximately 2 mm thick (e.g., 1 mm, 1.5 mm, 2.5 mm, or 3 mm)), another thermally conductive metal, or some plastic. In some cases, adequate thermal conductivity may be achieved with a less conductive material of appropriate geometry.

[0262] 4.6.2.3 Humidifier Reservoir Dock In one form, the humidifier 5000 may include a humidifier reservoir dock 5130 (as shown in FIG. 3V) configured to receive the humidifier reservoir 5110. In some arrangements, the humidifier reservoir dock 5130 may include a locking feature (e.g., a locking lever 5135 configured to hold the reservoir 5110 within the humidifier reservoir dock 5130).

[0263] 4.6.2.4 Water Level Indicator The humidifier reservoir 5110 may include a water level indicator 5150 as shown in Figures 3V-3W. In some forms, the water level indicator 5150 may provide one or more indications to a user, such as the patient 1000 or a caregiver, about the amount of water in the humidifier reservoir 5110. These one or more indications provided by the water level indicator 5150 may include an indication of a maximum predetermined amount of water, any portion thereof (e.g., 25%, 50%, or 75% or an amount (e.g., 200 ml, 300 ml, or 400 ml)).

[0264] 4.6.2.5 Heating elements In some cases, a heating element 5240 may be provided to the humidifier 5000 to provide heat input to one or more of the volume of water in the humidifier reservoir 5110 and / or the volume of water to the airflow. The heating element 5240 may include a heat-generating component, such as an electrical resistance heating track. One suitable example of a heating element 5240 is a layered heating element, for example, as described in WO 2012 / 171072, the entire contents of which are incorporated herein by reference.

[0265] In some forms, the heating element 5240 may be provided in the humidifier base 5006. In the humidifier base 5006, heat may be transferred to the humidifier reservoir 5110 primarily by conduction, as shown in Figure 5B.

[0266] 4.7 Glossary For purposes of this disclosure, in certain aspects of the technology, one or more of the following definitions may apply. In other aspects of the technology, other definitions may apply.

[0267] 4.7.1 General Air: In certain forms of the present technology, air may refer to atmospheric air, while in other forms of the present technology, air may refer to a combination of other breathable gases (e.g., oxygen-rich atmospheric air).

[0268] Atmosphere: In certain forms of the present technology, the term "atmosphere" should be taken to mean (i) that which is external to the treatment system or patient, and (ii) that which immediately surrounds the treatment system or patient.

[0269] For example, the ambient humidity for a humidifier may be the humidity of the air immediately surrounding the humidifier (e.g., the humidity inside the room where the patient is sleeping), which may differ from the humidity outside the room where the patient is sleeping.

[0270] In another example, the ambient pressure may be the pressure immediately surrounding or external to the body.

[0271] In certain embodiments, ambient (e.g., acoustic) noise can be considered the background noise level in the room the patient is in, other than noise emanating from, for example, the RPT device or from the mask or patient interface. Ambient noise can originate from sources outside the room.

[0272] Automatic Positive Airway Pressure (APAP) Therapy: A CPAP therapy that is capable of automatically adjusting therapeutic pressure between minimum and maximum limits, for example, between breaths, depending on the presence or absence of signs of an SDB episode.

[0273] Continuous Positive Airway Pressure (CPAP) Therapy: Respiratory pressure therapy in which the therapeutic pressure is approximately constant throughout the patient's respiratory cycle. In some forms, the pressure at the entrance to the airways increases slightly during exhalation and decreases slightly during inhalation. In some forms, the pressure varies during different respiratory cycles of the patient (e.g., increased in response to the detection of an indication of partial upper airway obstruction and decreased in the absence of notification of partial upper airway obstruction).

[0274] Flow Rate: The instantaneous amount (or mass) of air delivered per unit time. Flow rate can refer to an instantaneous quantity. In some cases, reference to flow rate refers to a scalar quantity (i.e., a quantity that has only magnitude). In other cases, reference to flow rate refers to a vector quantity (i.e., a quantity that has both magnitude and direction). Flow rate may be given the symbol Q. "Flow rate" may also be simply called "flow."

[0275] In the example of a patient's breathing, the flow rate may be nominally positive for the inspiratory portion of the patient's breathing cycle, and therefore negative for the expiratory portion of the patient's breathing cycle. Total flow rate Qt is the flow rate of air exiting the RPT device. Vent flow rate Qv is the flow rate of air exiting the vent to allow for the outflow of exhaled gases. Leakage flow rate Ql is the flow rate of leakage from the patient interface system or elsewhere. Respiratory flow rate Qr is the flow rate of air received into the patient's respiratory system.

[0276] Humidifier: The word "humidifier" is construed to mean a humidifying device constructed, arranged, or configured with a physical structure capable of providing a therapeutically beneficial quantity of water (H2O) vapor to an air stream to improve the medical respiratory condition of a patient.

[0277] Leak: The term "leak" refers to unintended airflow. In one example, a leak can occur due to an imperfect seal between the mask and the patient's face. In another example, a leak can occur at the elbow to the perimeter.

[0278] Noise Conduction (Acoustic): In this document, conducted noise refers to noise carried to the patient by the pneumatic path (e.g., the air circuit and patient interface and the air therein). In one form, conducted noise can be quantified by measuring the sound pressure level at the end of the air circuit.

[0279] Noise Emission (Acoustic): In this document, radiated noise refers to noise carried by the ambient air to the patient. In one form, radiated noise can be quantified by measuring the sound power / pressure level of the target in accordance with ISO 3744.

[0280] Ventilation noise (acoustic): In this document, ventilation noise refers to the noise generated by airflow through any ventilation (eg, ventilation holes in the patient interface).

[0281] Patient: A person with or without a respiratory disease.

[0282] Pressure: Force per unit area. Pressure can be expressed and measured in a variety of units (e.g., cmH2O, gf / cm 2 , and hectopascals). 1cmH2O is 1gf / cm 2 which is approximately 0.98 hectopascals. In this specification, pressures are given in units of cmH2O unless otherwise specified.

[0283] The pressure in the patient interface is designated by the symbol Pm, and the therapeutic pressure, which represents the target value that the mask pressure Pm should achieve at this time, is designated by the symbol Pt.

[0284] Respiratory Pressure Therapy (RPT): The application to the airway entrance of an air supply at therapeutic pressure, typically positive pressure relative to atmosphere.

[0285] Ventilator: A mechanical device that provides pressure support to a patient while they perform some or all of the work of breathing.

[0286] 4.7.1.1 Materials Silicone or silicone elastomer: Synthetic rubber. References to silicone herein refer to liquid silicone rubber (LSR) or compression molded silicone rubber (CMSR). One commercially available form of LSR is SILASTIC (in a family of products sold under this registered trademark) manufactured by Dow Corning. Another LSR manufacturer is Wacker. Unless otherwise specified, exemplary forms of LSR have a Shore A (or Type A) indentation hardness of about 35 to about 45, as measured by ASTM D2240.

[0287] Polycarbonate: A thermoplastic polymer of bisphenol A carbonate. 4.7.1.2 Mechanical properties

[0288] Elasticity: The ability of a material to absorb energy during elastic deformation and to release the energy when unloaded.

[0289] Elastic: Releases substantially all of the energy upon unloading. Examples include certain silicone and thermoplastic elastomers.

[0290] Hardness: The ability of a material to resist deformation (e.g., as described by Young's modulus or the indentation hardness scale measured on a standardized sample size). "Soft" materials may include silicone or thermoplastic elastomers (TPEs) and may easily deform under finger pressure, for example. "Hard" materials may include polycarbonate, polypropylene, steel or aluminum, and do not easily deform under finger pressure, for example.

[0291] Stiffness (or rigidity) of a structure or component: The ability of a structure or component to resist deformation when subjected to a load. The load can be a force or a moment (e.g., compression, extension, bending, or torsion). A structure or component may offer different resistance in different directions.

[0292] Floppy structure or component: A structure or component that changes shape (e.g., flexes) within a relatively short period of time (e.g., 1 second) when forced to support its own weight.

[0293] Rigid structure or component: A structure or component that does not substantially change shape when subjected to loads typically encountered in use. An example of such an application would be setting up and maintaining a patient interface in a sealed manner against a patient airway entrance under a pressure load of, for example, approximately 20-30 cmH2O.

[0294] As one example, an I-beam may have a different bending stiffness (resistance to bending load) in a first direction compared to a second, orthogonal direction. In another example, a structure or component may be floppy in a first direction and rigid in a second direction.

[0295] 4.7.2 Respiratory cycle Apnea: According to some definitions, apnea is said to occur when flow below a predetermined threshold continues for a duration of, for example, 10 seconds. Obstructive apnea is said to occur when some airway obstruction does not allow airflow despite patient effort. Central apnea is said to refer to a condition in which apnea is detected due to reduced or absent respiratory effort despite a patent airway. Mixed apnea is said to refer to a condition in which reduced or absent respiratory effort occurs simultaneously with airway obstruction.

[0296] Respiratory rate: The patient's spontaneous breathing rate, usually measured in breaths per minute.

[0297] Duty cycle: The ratio of inspiration time Ti to total breathing time Ttot.

[0298] Exercise (Respiration): Respiratory effort is said to refer to the movement made by the spontaneous breathing of a person trying to breathe.

[0299] Expiratory portion of the respiratory cycle: the period from the start of expiratory flow to the start of inspiratory flow.

[0300] Flow limitation: Flow limitation is understood to be a condition in a patient's breathing where an increase in patient effort does not result in a corresponding increase in flow. If flow limitation occurs during the inspiratory portion of the respiratory cycle, the flow limitation can be referred to as inspiratory flow limitation. If flow limitation occurs during the expiratory portion of the respiratory cycle, the flow limitation can be referred to as expiratory flow limitation.

[0301] Flow-limited inspiration waveform types: (i) Flattening: An upswing followed by a relatively flat area, followed by a downswing. (ii) M-shaped: has two local peaks, one at the rise and one at the fall, with a relatively flat region between these two peaks. (iii) Chair-like: A single local peak occurs at the rising part, followed by a relatively flat region. (iv) Inverted chair: A relatively flat region is followed by a single local peak, which occurs on the trailing edge.

[0302] Hypopnea: By some definitions, hypopnea refers to a reduction in flow, rather than an interruption of flow. In one form, hypopnea is said to occur when flow is reduced below a threshold rate for a sustained period of time. When hypopnea is detected due to a decrease in respiratory effort, central hypopnea is said to occur. In one form, hypopnea may be considered when any of the following occur in adults: (i) A 30% decrease in patient respiration for at least 10 seconds plus an associated 4% desaturation, or (ii) A reduction in patient respiration (less than 50%) lasting at least 10 seconds and associated desaturation of at least 3% or arousal occurs.

[0303] Hyperventilation: An increase in flow to a level higher than normal.

[0304] Inspiratory portion of the respiratory cycle: The period from the start of the inspiratory flow to the start of the expiratory flow is taken as the inspiratory portion of the respiratory cycle.

[0305] Patency (Airway): The degree to which the airway is open or the extent to which it is open. Airway patency is an opening. Airway patency can be quantified, for example, with a value of 1 indicating open and a value of 0 indicating closed (obstructed).

[0306] Positive end-expiratory pressure (PEEP): The pressure above atmosphere in the lungs that exists at the end of expiration.

[0307] Peak flow (Qpeak): The maximum value of flow during the inspiratory portion of the respiratory flow waveform.

[0308] Respiratory airflow, airflow, patient airflow, respiratory airflow (Qr): These terms may be understood to refer to the RPT device's estimate of respiratory airflow, and are used in contrast to "true respiratory flow" or "true respiratory airflow," which is the patient's actual respiratory flow, usually expressed in liters / minute.

[0309] Tidal Volume (Vt): The volume of air inhaled or exhaled during normal breathing without extra effort.

[0310] (Inspiration) Time (Ti): The duration of the inspiratory portion of the respiratory flow waveform.

[0311] (Expiratory) Time (Te): The duration of the expiratory portion of the respiratory flow waveform.

[0312] (Total) Time (Ttot): The total duration between the start of one inspiratory portion of the respiratory flow waveform and the start of the next inspiratory portion of the respiratory flow waveform.

[0313] Typical Recent Ventilation: The ventilation value around which recent values ​​of ventilationVent over a given time scale tend to cluster (i.e., the degree to which recent values ​​of ventilation tend to be centered).

[0314] Upper Airway Obstruction (UAO): Includes both partial and total upper airway obstruction. May be associated with a state of flow limitation in which flow may increase or decrease slightly with increasing pressure differential across the upper airway (Starling resistor behavior).

[0315] Vent: A measure of the rate of gas exchange performed by a patient's respiratory system. Measurements of ventilation may include either or both inspiratory and expiratory flow per unit time. When expressed as volume per minute, this quantity is often referred to as "minute ventilation." Minute ventilation is sometimes given simply as volume and is understood as volume per minute.

[0316] 4.7.3 Ventilation Adaptive servo-ventilator (ASV): A servo-ventilator that does not have a fixed target ventilation but is variable. The variable target ventilation can be learned from some characteristic of the patient (e.g., the patient's breathing characteristics).

[0317] Backup Rate: A ventilator parameter that establishes the minimum respiratory rate (typically in breaths per minute) that will be delivered to the patient by the ventilator (when not triggered by spontaneous breathing efforts).

[0318] Cycle: The end of the inspiratory phase of a ventilator. When a ventilator delivers breaths to a spontaneously breathing patient, at the end of the inspiratory portion of the breathing cycle, the ventilator is said to be cycled to stop breath delivery.

[0319] Expiratory Positive Airway Pressure (EPAP): The base pressure to which varying pressures are added during a breath to produce the desired mask pressure that the ventilator attempts to achieve at a given moment.

[0320] End Expiratory Pressure (EEP): The desired mask pressure that the ventilator attempts to achieve at the end of the expiratory portion of the breath. If the pressure waveform template Π(Φ) has a value of zero at the end of expiration (i.e., Π(Φ)=0 when Φ=1), then EEP is equal to EPAP.

[0321] Inspiratory Positive Airway Pressure (IPAP): The maximum desired mask pressure that the ventilator attempts to achieve during the inspiratory portion of the breath.

[0322] Pressure Support: A number indicating the increase in pressure during ventilator inspiration compared to the corresponding ventilator expiration, and refers primarily to the pressure difference between the maximum inspiratory pressure and the base pressure (e.g., PS = IPAP - EPAP). In some contexts, pressure support refers to the difference the ventilator attempts to achieve (rather than the difference it actually achieves).

[0323] Servo-ventilator: A ventilator that has both patient ventilation and target ventilation, and adjusts the level of pressure support to bring the patient ventilation closer to the target ventilation.

[0324] Spontaneous / Timed (S / T): A mode of a ventilator or other device that attempts to detect the onset of a breath in a spontaneously breathing patient. However, if the device fails to detect a breath within a predetermined period of time, the device automatically begins breath delivery.

[0325] Swing: A term equivalent to pressure assistance.

[0326] Triggered: When a ventilator delivers a breath of air to a spontaneously breathing patient, the ventilator is said to be triggered to deliver a breath when the patient himself initiates the breathing portion of the breathing cycle.

[0327] Typical Recent Ventilation: Typical recent ventilation Vtyp is a range of values ​​around which recent ventilation measurements tend to cluster over a given time scale. For example, a measure of the central tendency of ventilation measurements over recent history may be an appropriate value for typical recent ventilation.

[0328] 4.7.4 Anatomy 4.7.4.1 Facial Anatomy Ala: the outer wall or "wing" of each nostril (plural: alar)

[0329] Alare: The outermost point on the ala of the nose.

[0330] Alar curvature (or alar crest) point: The most posterior point on the curved baseline of each alar, found in the crease formed by the union of the alar and cheek.

[0331] Pinna: the entire visible part of the ear.

[0332] (Nasal) skeleton: The nasal skeleton includes the nasal bones, the frontal process of the maxilla, and the nasal portion of the frontal bone.

[0333] (Nasal) cartilaginous rami: The cartilaginous rami of the nose include the nasal septum, lateral nasal cartilages, greater cartilages, and lesser cartilages.

[0334] Columella: The piece of skin that separates the nostrils and extends from the tip of the nose to the upper lip.

[0335] Columella angle: the angle between a line drawn through the midpoint of the nostril and a line drawn perpendicular to the Frankfurt horizontal and intersecting the subnasal point.

[0336] Frankfort horizontal plane: A line extending from the most inferior point of the orbital rim to the left auricular point, which is the deepest point of the auricle from the superior side of the notch to the tragus.

[0337] Glabellar: Located in the soft tissue, the most prominent point in the midsagittal direction of the forehead.

[0338] Lateral nasal cartilage: roughly triangular plate of cartilage, the upper margin of which is attached to the nasal bone and the frontal process of the maxilla, and the lower margin of which is connected to the greater alar cartilage.

[0339] Alar cartilage: a cartilaginous plate located below the lateral nasal cartilage. It curves around the anterior part of the nostril. Its posterior end is connected to the frontal process of the maxilla by a tough fibrous membrane containing three or four alar cartilages.

[0340] Nostrils (nose holes): roughly ellipsoidal alar openings that form the entrance to the nasal cavity. The singular form of nostril is nostril (nostril). These nostrils are separated by the nasal septum.

[0341] Nasolabial fold or nasolabial crease: a fold or groove of skin that extends from each side of the nose to the corners of the mouth, separating the cheek from the upper lip.

[0342] Nasolabial angle: the angle between the bridge of the nose and the upper lip, intersecting with the subnasal point.

[0343] Subbasal point of the ear: the lowest point of attachment of the pinna to the facial skin.

[0344] Suprabasal point of the ear: the highest point of attachment of the pinna to the facial skin.

[0345] Nasal tip: The most prominent point or tip of the nose, which can be seen in a lateral view of the rest of the head.

[0346] Philtrum: midline groove extending from the lower border of the nasal septum to the top of the lip in the upper lip area.

[0347] Pogonion: The most anterior midpoint of the jaw, located on the soft tissue.

[0348] Nasal ridge: The nasal ridge is the midline prominence of the nose, extending from the serion to the apex.

[0349] Sagittal plane: a vertical plane running from anterior (front) to posterior (back) that divides the body into right and left halves.

[0350] Cerion: Located on the soft tissue, it is the most concave point on the area of ​​the frontonasal suture.

[0351] Septal cartilage (nose): The nasal septum cartilage is part of the septum, which divides the anterior part of the nasal cavity.

[0352] Nasal alar nasal basin: the point on the lower periphery of the alar base where it joins with the skin of the upper (top) lip.

[0353] Subnasal point: Located on the soft tissue, the point where the columella joins the upper lip in the midsagittal plane.

[0354] Supramentale: The most concave point in the midline of the lower lip between the lower lip midpoint and the soft tissue pogonion.

[0355] 4.7.4.2 Skull anatomy Frontal bone: The frontal bone contains the squama frontalis, a large vertical portion that corresponds to the area known as the forehead.

[0356] Mandible: The mandible forms the lower jaw. The mental protuberance is a bony protuberance in the jaw, forming the chin.

[0357] Maxilla: The maxilla forms the upper jaw and is located below the mandible and below the orbit. The frontal process of the maxilla projects upward by the sides of the nose and forms part of its lateral border.

[0358] Nasal bones: The nasal bones are two small, rectangular bones that vary in size and shape from person to person. They lie side by side in the middle and upper parts of the face, and their junction forms the "bridge" of the nose.

[0359] Nasion: the intersection of the frontal bone and the two nasal bones, a concave area directly between the eyes and the upper side of the bridge of the nose.

[0360] Occipital bone: The occipital bone is located at the back and underside of the skull. It contains the foramen magnum, an oval hole through which the intracranial cavity connects with the vertebral canal. The curved plate posterior to the foramen magnum is the squama occipitalis.

[0361] Orbit: bony cavity in the skull that contains the eyeball.

[0362] Parietal bones: The parietal bones are bones that, when joined together, form the top and sides of the skull.

[0363] Temporal bone: The temporal bone is located on the base and sides of the skull and supports parts of the face known as the temples.

[0364] Cheekbones: The two cheekbones in the face are located in the upper and outer parts of the face and form the cheek ridges.

[0365] 4.7.4.3 Respiratory system anatomy Diaphragm: A sheet of muscle that runs over the lower rib cage. The diaphragm separates the thoracic cavity, which contains the heart, lungs, and ribs, from the abdominal cavity. When the diaphragm contracts, it increases the volume of the thoracic cavity and draws air into the lungs.

[0366] Larynx: The larynx or voice box that houses the vocal cords and connects the lower part of the pharynx (hypopharynx) to the trachea.

[0367] Lung: respiratory organ in humans. The conductive zone of the lung includes the trachea, bronchi, bronchi, and terminal bronchioles. The respiratory zone includes the respiratory bronchioles, alveolar ducts, and alveoli.

[0368] Nasal Cavity: The nasal cavity (or nasal fossa) is a large, air-filled space in the center of the face above and behind the nose. The nasal cavity is divided into two by a vertical fin called the nasal septum. The sides of the nasal cavity contain three horizontal extensions called turbinates or nasal conchae. The nasal cavity opens anteriorly into the nose and posteriorly into the nasopharynx via the choanae.

[0369] Pharynx: The part of the throat located immediately below (inferior to) the nasal cavity and above the esophagus and larynx. The pharynx is traditionally divided into three parts: the nasopharynx (upper pharynx) (nasal part of the pharynx), the oropharynx (middle pharynx) (oral part of the pharynx), and the hypopharynx (low pharynx).

[0370] 4.7.5 Patient Interface Anti-asphyxiation valve (AAV): A component or subassembly of a mask system that vents to atmosphere in a fail-safe manner to reduce the risk of excessive CO2 rebreathing by the patient.

[0371] Elbow: An elbow is an example of a structure that directs the axis of airflow moving therethrough to change direction through an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be greater than or less than 90 degrees. The elbow may have a generally circular cross section. In another form, the elbow may have an oval or rectangular cross section. In certain forms, the elbow may be rotatable relative to the mating component, for example, approximately 360 degrees. In certain forms, the elbow may be detachable from the mating component, for example, via a snap connection. In certain forms, the elbow may be assembled to the mating component via a one-time snap during manufacturing, but cannot be removed by the patient.

[0372] Frame: Frame is taken to mean the mask structure that supports the tensile load between two or more points that connect the headgear. A mask frame can be a non-airtight load-bearing structure in the mask. However, some forms of mask frames may be airtight.

[0373] Headgear: Headgear is taken to mean a form of positioning and stabilizing structure designed for use on the head. For example, the headgear may include a collection of one or more posts, ties, and stiffeners configured to position and hold the patient interface in place on the patient's face for delivery of respiratory therapy. Some ties are formed from a soft, flexible, elastic material (e.g., a layered composite of foam and fabric).

[0374] Membrane: Membrane is taken to mean a typically thin-walled element, preferably substantially non-resistant to bending and resistant to stretching.

[0375] Plenum Chamber: Mask plenum chamber is taken to mean a part of a patient interface having walls that at least partially enclose a volume of space, the air in the volume being pressurized to exceed atmospheric pressure in use. The shell may form part of the wall of the mask plenum chamber.

[0376] Seal: When used as a noun ("seal"), it can refer to a structure, and when used as a verb ("to seal"), it can refer to an effect. Two elements can be constructed and / or arranged to "seal" or achieve a "sealing" effect between them without the need for a separate "sealing" element itself.

[0377] Shell: A shell is taken to mean a curved, relatively thin structure that has bending, tensile, and compressive stiffness. For example, the curved structural wall of a mask may be a shell. In some forms, the shell may be faceted. In some forms, the shell may be airtight. In some forms, the shell may not be airtight.

[0378] Stiffener: A stiffener is taken to mean a structural component designed to increase the bending resistance of another component in at least one direction.

[0379] Strut: A strut is taken to mean a structural component designed to increase the compressive resistance of another component in at least one direction.

[0380] Swivel (noun) A subassembly of components configured to rotate, preferably independently, about a common axis, preferably under low torque. In one form, the swivel may be configured to rotate through an angle of at least 360 degrees. In another form, the swivel may be configured to rotate through an angle of less than 360 degrees. When used in the context of an air delivery conduit, the component subassembly preferably includes a mating cylindrical conduit. In use, there is little or no air leakage from the swivel.

[0381] Tie (noun): A structure designed to resist tension.

[0382] Venting: (noun): A structure that allows airflow into the ambient atmosphere inside a mask or conduit, allowing clinically effective flushing of exhaled gases. For example, for clinically effective flushing, flow rates of about 10 liters / minute to about 100 liters / minute may be used depending on mask design and treatment pressure.

[0383] 4.7.6 Structural Shape Products of the present technology may include one or more three-dimensional mechanical structures (e.g., a mask cushion or impeller). The three-dimensional structures may be bounded by two-dimensional surfaces. These surfaces may be distinguished using labels to describe the orientation, location, function, or some other characteristic of the associated surfaces. For example, the structure may include one or more of a front surface, a back surface, an interior surface, and an exterior surface. In another example, the cushion structure may include a face-containing (e.g., exterior) surface and a separate face-free (e.g., lower or interior) surface. In another example, the structure may include a first surface and a second surface.

[0384] To facilitate the description of the shape and surface of a three-dimensional structure, we first consider a cross section at a point p through the surface of the structure. See Figures 3B-3F. Figures 3B-3F show an example cross section at point p on the surface and an example of the resulting planar curve. Figures 3B-3F also show the outward normal vector at p. The outward normal vector at p points away from the surface. In some examples, the surface is described from the perspective of a fictitious little person standing upright on the surface.

[0385] 4.7.6.1 Curvature in one dimension The curvature of a plane curve at p can be described as having a sign (eg, positive, negative) and a magnitude (eg, 1 / radius of the circle tangent to the curve at p).

[0386] Positive curvature: If the curve at p bends toward the outward normal, the curvature at that point is taken to have a positive value (if our fictitious little person were to walk away from point p, they would have to walk uphill). See Figure 3B (relatively large positive curvature compared to Figure 3C) and Figure 3C (relatively small positive curvature compared to Figure 3B). Such curves are often called concave.

[0387] Zero curvature: If the curve at p is a straight line, the curvature is taken as zero (if this imaginary little person walks away from point p, they can walk on a horizontal plane that is neither pointing up nor pointing down). See Figure 3D.

[0388] Negative curvature: If the curve at p bends away from the outward normal, the curvature at that point and in that direction is taken to have a negative value (if this fictitious little person were to walk away from point p, they would have to walk downhill). See Figure 3E (relatively small negative curvature compared to Figure 3F) and Figure 3F (relatively large negative curvature compared to Figure 3E). Such curves are often called convex.

[0389] 4.7.6.2 Curvature of two-dimensional surfaces A description of a shape at a given point on a two-dimensional surface according to the present technology may include multiple perpendicular cross sections. The multiple cross sections may cut the surface in a plane containing the outward normal (the "normal plane"), and each cross section may be taken in a different direction. Each cross section results in a plane curve with a corresponding curvature. The different curvatures at the point may have the same or different signs. Each curvature at the point has a (e.g., relatively small) magnitude. The plane curves in Figures 3B-3F may be examples of such multiple cross sections at a particular point.

[0390] Principal curvature and direction: The directions of the normal plane in which the curvature of a curve reaches its maximum and minimum values ​​are called the principal directions. In the example of Figures 3B-3F, the maximum curvature occurs in Figure 3B and the minimum occurs in Figure 3F, so Figures 3B and 3F are cross sections in the principal directions. The principal curvature at p is the curvature in the principal direction.

[0391] Surface region: A set of connected points on a surface. This set of points within a region may have similar properties (e.g., curvature or sign).

[0392] Saddle region: A region where the principal curvatures at each point have opposite signs (i.e., one positive sign and the other negative sign) (depending on the direction a hypothetical person who may be walking uphill or downhill is facing).

[0393] Dome area: an area where the principal curvatures at each point have the same sign: either both positive ("concave dome") or both negative ("convex dome")

[0394] Cylindrical region: A region in which one principal curvature is zero (or, for example, zero within manufacturing tolerances) and the other principal curvature is non-zero.

[0395] Planar region: A region of a surface where both principal curvatures are zero (or are zero within a manufacturing tolerance, for example).

[0396] Surface Edge: The boundary or limit of a surface or area.

[0397] Path: In certain forms of the present technology, a "path" is taken to mean a path in the mathematical-topological sense (e.g., a continuous space curve from f(0) to f(1) on a surface). In certain forms of the present technology, a "path" may be described as a route or course that includes, for example, a set of points on a surface. (A hypothetical person's path is a place they walk on a surface, similar to a path in a garden.)

[0398] Path Length: In certain forms of the present technology, "path length" is taken to refer to the distance along the surface from f(0) to f(1) (i.e., the distance along a path on the surface). There may be more than one path between two points on the surface, and such paths may have different path lengths. (The path length of a fictional person is the distance walked along the path on the surface.)

[0399] Straight-line distance: Straight-line distance is the distance between two points on a surface, but does not take the surface into account. On a planar area, there is a distance on the surface edge that has the same path length as the straight-line distance between two points on the surface. On a non-planar surface, there cannot be a path that has the same path length as the straight-line distance between two points. (For a fictional person, straight-line distance corresponds to the distance as the crow flies.)

[0400] 4.7.6.3 Space curve Space Curve: Unlike a plane curve, a space curve does not necessarily exist in any particular plane. A space curve can be considered a one-dimensional piece of three-dimensional space. A fictional character walking on a strand of DNA helix walks along a space curve. A typical human left ear contains a left-handed helix (see Figure 3Q). A typical human right ear contains a right-handed helix (see Figure 3R). Figure 3S shows a right-handed helix. The edge of a structure (e.g., the edge of a membrane or impeller) can trace a space curve. In general, a space curve can be described by the curvature and twist at each point on the space curve. Twist is a measure of the way the curve emanates from the plane. Twist has a sign and a magnitude. The twist at a point on a space curve can be characterized with respect to the tangent, normal, and binormal vectors at that point.

[0401] Tangent unit vector (or unit tangent vector): For each point on a curve, the vector at that point specifies the direction and magnitude from that point. A tangent unit vector is a unit vector that points in the same direction as the curve at that point. If a fictional character were flying along the curve and fell off their vehicle at a particular point, the direction of the tangent vector would be the direction they would be traveling.

[0402] Unit normal vector: As the fictional character moves along the curve, this tangent vector itself changes. The unit vector that points in the same direction as the tangent vector is changing is called the unit principal normal vector. It is perpendicular to the tangent vector.

[0403] Binormal unit vector: The binormal unit vector is perpendicular to both the tangent vector and the principal normal vector. Its direction can be determined by the right-hand rule (see, for example, Figure 3P) or the left-hand rule (Figure 3O).

[0404] Oscillating plane: the plane containing the unit tangent vector and the unit principal normal vector. See Figures 3O and 3P.

[0405] Torsion of a Space Curve: The torsion at a point on a space curve is the magnitude of the rate of change of the binormal unit vector at that point. It measures the degree of deviation of the curve from the tangential plane. A space curve that lies within a plane has zero torsion. If the space curve deviates from the tangential plane by a relatively small amount, the magnitude of torsion of the space curve is relatively small (e.g., a gently sloping spiral path). If the space curve deviates from the tangential plane by a relatively large amount, the magnitude of torsion of the space curve is relatively large (e.g., a steeply sloping spiral path). Referring to Figure 3S, because T2 > T1, the magnitude of torsion near the top coil of the spiral in Figure 3S is greater than the magnitude of torsion of the bottom coil of the spiral in Figure 3S.

[0406] Referring to the right-hand rule in Figure 3P, a space curve that bends toward the right-hand binormal can be considered to have a positive right-hand twist (e.g., a right-hand spiral as shown in Figure 3S). A space curve that bends away from the right-hand binormal can be considered to have a negative right-hand twist (e.g., a left-hand spiral).

[0407] Similarly, with reference to the left-hand rule (see Figure 3O), a space curve oriented in a left-handed binormal direction can be considered as having a positive left-handed twist (e.g., a left-handed spiral). Thus, a positive left-handed direction corresponds to a negative right-handed direction. See Figure 3T.

[0408] 4.7.6.4 Holes A surface may have one-dimensional holes (e.g., holes bounded by a planar or space curve). In the case of a thin structure (e.g., a membrane) that contains holes, the structure may be described as having one-dimensional holes. See, for example, how the one-dimensional holes in the surface of the structure shown in Figure 3I are bounded by a planar curve.

[0409] A structure can have a two-dimensional hole (e.g., a hole bounded by a surface). For example, an inflatable tire has a two-dimensional hole bounded by the tire's inner surface. In another example, a bladder with a cavity for air or gel can have a two-dimensional hole. See, for example, the cushion in FIG. 3L and the exemplary cross-section of FIG. 3L in FIGS. 3M and 3N, where the inner surface bounding the two-dimensional hole is shown. In yet another example, a conduit can include a one-dimensional hole (e.g., at its inlet or its outlet) and can include a two-dimensional hole bounded by the inner surface of the conduit. See also the two-dimensional hole through the structure shown in FIG. 3K and bounded by a surface as shown.

[0410] 4.8 Other Notes A portion of the disclosure of this patent document contains material that is entitled to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of this patent document or this patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but reserves all copyright rights therefor for all other purposes.

[0411] Unless otherwise clearly indicated from the context and unless a range of values ​​is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit, between the upper and lower limits of the range, and for any other stated or intervening value in the stated range, is encompassed by the technology. The upper and lower limits of these intervening ranges, independently included in the intervening range, are also encompassed by the technology if they specifically exceed the limits in the stated range. If the stated range includes one or both of these limits, then ranges exceeding either or both of these stated limits are also encompassed by the technology.

[0412] Furthermore, when a value or values ​​are embodied herein as part of the present technology, unless otherwise specified, it is understood that such values ​​may be approximated and may be used to any appropriate significant figures to the extent practical technical practice permits or requires.

[0413] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of this technology, a limited number of exemplary methods and materials are described herein.

[0414] Although particular materials are described as being suitable for use in the construction of components, obvious alternative materials having similar properties may be substituted. Furthermore, unless stated to the contrary, any and all components described herein are understood to be manufacturable and therefore may be manufactured collectively or separately.

[0415] Please note that as used herein and in the appended claims, the singular forms "a," "an," and "the" include their plural equivalents unless the context clearly dictates otherwise.

[0416] All publications mentioned herein are incorporated by reference to disclose and describe the methods and / or materials that are the subject of these publications. The publications mentioned herein are provided solely for their disclosure prior to the filing date of this application. Nothing herein should be construed as an admission that the present technology does not antedate such publications by virtue of prior patents. Furthermore, the dates of publications mentioned may differ from the actual publication dates, which may require independent confirmation.

[0417] The terms "comprises" and "comprising" should be construed as referring to elements, components, or steps in a non-exclusive sense, indicating that a described element, component, or step may be present in, utilized with, or combined with other elements, components, or steps not specifically described.

[0418] The headings used in the detailed description are for the convenience of the reader and should not be used to limit the content found in the disclosure or claims as a whole. These headings should not be used in interpreting the scope of the claims or the claim limitations.

[0419] Although the technology herein has been described with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the technology. In some cases, terms and symbols may indicate specific details unnecessary for the practice of the technology. For example, although the terms "first" and "second" (etc.) are used, unless otherwise specified, these terms are not intended to indicate any order but are used to distinguish between separate elements. Furthermore, although the process steps in the method may be described or illustrated in an ordered manner, such an order is not required. Those skilled in the art will recognize that such an order can be changed and / or aspects can be performed simultaneously or even synchronously.

[0420] It is therefore to be understood that numerous modifications may be made in the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present technology. [Explanation of symbols]

[0421] 4.9 List of Reference Symbols 1000 patients 1100 Bedmate 3000 Patient Interface 3100 Seal forming structure 3105 Sealed surface 3110 Joint material 3111 Edge 3115 Outer perimeter 3120 Tubular Structure 3125 Sealing flap 3130 Thick meat parts 3135 Thin parts 3140 Hinge structure 3145 Mounting location 3150 Flap 3155 Rib 3160 Flap 3165 Connection Points 3170 angle 3175 area 3175A area 3175B area 3175C area 3175D area 3175E Area 3175F area 3200 Plenum Chamber 3210 Edge 3220 Peripheral edge 3300 Structure 3400 Ventilation 3600 connection port 3700 Forehead support 3800 Cushion Assembly 3810 Cushion 3810 Foam cushion 3812 Flexible Support Clip 3814 Second Clip 3816 Mask Shell 3818 sagittal plane 3820 line 3825 First Tangent 3830 Second Tangent 3835 Support structure 3840 Nose bridge area 3845 Jaw area 3850 Intermediate area 3855 Folding Section 4000 RPT devices 4170 Air Circuit 5000 humidifier 6000 Structure 6005 area 6005A area 6005B area 6005C area 6005D area 6005F area 6005G area

Claims

1. 1. A cushion assembly for a patient interface that delivers a flow of air at a continuous positive pressure relative to ambient air pressure to an entrance to a patient's airways, including at least the entrance to the patient's nostrils, in a sealed manner, the patient interface providing a pressure of approximately 4 cmH above ambient air pressure throughout the patient's breathing cycle while the patient is asleep. ２ O ~ approx. 30cmH ２ and maintaining a therapeutic pressure in the range of O to improve sleep-disordered breathing; The cushion assembly includes: a foam cushion configured to sealingly engage the patient's face; an elastomeric support portion configured to support the foam cushion and to form at least a portion of a plenum chamber with the foam cushion, the elastomeric support portion including a pair of ribs positioned on either side of the patient's nose in use such that the elastomeric support portion provides different levels of support in different regions of the elastomeric support portion; Including, the elastomeric support region includes a support structure and a bent section extending radially inward from the support structure, the bent section forming an angle with the support structure; the folded section acts as a seat for the foam cushion; each rib attached to a side of the fold section of the elastomeric support element, the side of the fold section being opposite the side of the fold section to which the foam cushion is attached; the foam cushion overhangs the folded section such that the foam cushion can rotate inward toward the interior of the plenum chamber in response to a compressive force acting on the foam cushion; A cushion assembly, wherein the amount of the foam cushion that overhangs the folded section varies in different regions of the cushion assembly.

2. The cushion assembly of claim 1 , wherein the width of the folded section varies across different areas of the elastomeric support region.

3. 3. The cushion assembly of claim 1 or 2, wherein the amount of overhang is relatively less in a chin region of the cushion assembly that is configured to engage the bridge of a patient's nose in use.

4. 4. The cushion assembly of claim 1, wherein the amount of overhang is relatively less in a nasal bridge region of the cushion assembly that is configured to engage a patient's chin in use.

5. 5. The cushion assembly of claim 1, wherein an angle between the folded section and the support structure allows the foam cushion to rotate inward toward an interior of the plenum chamber in response to a compressive force acting on the foam cushion.

6. The cushion assembly of claim 1 , wherein the angle between the folded section and the support structure is constant throughout the elastomeric support region.

7. The cushion assembly of claim 1 , wherein the angle between the folded section and the support structure varies in different regions of the elastomeric support region.

8. The cushion assembly of claim 1 , wherein each rib is compressible.

9. 9. The cushion assembly of claim 1, wherein each rib is more resistant to tension than to compression.

10. The cushion assembly of claim 1 , wherein different portions of the elastomeric support region have different stiffnesses.

11. 11. The cushion assembly of claim 1, wherein the elastomeric support region is more compressible in a nasal bridge region of the cushion assembly configured to engage the bridge of the patient's nose in use.

12. 12. The cushion assembly of claim 11, wherein the elastomeric support region has less compressibility in a chin region or an upper lip region than in the nasal bridge region, the chin region being at a location on the cushion assembly configured to engage a patient's chin in use, and the upper lip region being at a location on the cushion assembly configured to engage a patient's upper lip in use.

13. The cushion assembly of claim 12 , wherein the elastomeric support portion is least compressible in an intermediate region between the nasal bridge portion and the chin portion or between the nasal bridge portion and the upper lip portion.

14. The cushion assembly of claim 13 , wherein the rib is positioned in the intermediate region.

15. The cushion assembly of claim 1 , wherein the pair of ribs have the same elastomeric wall thickness.

16. The cushion assembly of claim 1 , wherein the pair of ribs have different elastomeric wall thicknesses.

17. The cushion assembly of claim 1 , wherein the wall thickness of the elastomeric support region varies in different regions of the cushion assembly.

18. 18. The cushion assembly of claim 1, wherein the depth of the elastomeric support region varies in different regions of the cushion assembly.

19. 1. A patient interface comprising: A cushion assembly according to any one of claims 1 to 18; a rigid shell removably connected to the cushion assembly; headgear removably attached to the rigid shell; a patient interface including:

20. 1. A CPAP system comprising:

20. A patient interface according to claim 19; a flow generator configured to pressurize the gas flow; an air delivery conduit configured to deliver pressurized gas to the patient interface; 1. A CPAP system comprising:

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