Steam ablation system and method

Abstract

A steam delivery system and method suitable for treating prostate tissue is provided. The steam delivery system includes a steam delivery needle configured to deliver condensable steam energy to tissue. In one method, the steam delivery system is advanced into a patient through the urethra to reach prostate tissue. The steam delivery system includes a generator unit and an induction heating system to generate high-quality steam for delivery to tissue. Methods of use are also provided.

Description

[0001] This application is a divisional application of the Chinese patent application with the application date of January 29, 2016, the national application number of 201680007738.8 (PCT application number of PCT / US2016 / 015684), and the name of “Steam Ablation System and Method”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 109,540, filed on January 29, 2015, entitled “VAPORABLATION SYSTEMS AND METHODS,” which is incorporated herein by reference in its entirety.

[0004] Combination of citations

[0005] All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. Technical Field

[0006] The present invention relates to apparatus and related methods for treating benign prostatic hyperplasia using minimally invasive methods. More particularly, the present invention relates to treating benign prostatic hyperplasia using steam delivered to the prostate. Background Art

[0007] Benign prostatic hyperplasia (BPH) is a common disease in middle-aged and older men, and its prevalence increases with age. At the age of 50, more than half of men have symptoms of BPH, and at the age of 70, nearly 90% of men have microscopic evidence of prostate enlargement. The severity of the symptoms also increases with age, with 27% of patients in the 60-70 age group having moderate to severe symptoms and 37% of patients in their 70s having moderate to severe symptoms.

[0008] In the early stage of life, the prostate has the size and shape of a walnut, weighing about 20 grams before hypertrophy caused by BPH. It seems that the enlargement of the prostate is a normal process. As the age increases, the size of the prostate gradually increases to twice or more of its normal size. After the gland reaches a certain size, the fibromuscular tissue of the outer prostate capsule limits expansion. Due to this limitation of expansion, the intracapsular tissue will press against and limit the prostatic urethra, resulting in resistance to urine flow thus.

[0009] In male urogenital anatomy, the prostate gland is located below the bladder and bladder neck. The bladder wall can expand and contract to cause urine to flow through the urethra, which extends from the bladder through the prostate and penis. The portion of the urethra surrounded by the prostate gland is called the prostatic urethra. The prostate also surrounds the ejaculatory duct, which has an open terminal in the prostatic urethra. During sexual stimulation, the vas deferens transports sperm from the testicles to the prostate, and the prostate provides fluid that combines with sperm to form semen during ejaculation. The vas deferens and the seminal vesicles are connected on each side of the prostate to form a single tube called the ejaculatory duct. Therefore, each ejaculatory duct transports seminal vesicle secretions and sperm into the prostatic urethra.

[0010] The prostate gland structure can be divided into three areas: peripheral zone, transition zone and central zone. The peripheral zone PZ includes the volume of the prostate of about 70% of young men. The subcapsular part of the rear of the prostate gland surrounds the distal urethra, and 70-80% of cancers originate from the peripheral zone tissue. The central zone CZ surrounds the ejaculatory duct and includes about 20-25% of the prostate volume. The central zone is usually the site of the inflammatory process. The transition zone TZ is the site where benign prostatic hyperplasia develops, and includes about 5-10% of the volume of glandular elements in the normal prostate, but can constitute up to 80% of this volume in the case of BPH. The transition zone includes two lateral prostate lobes and the periurethral glandular area. There is a natural barrier around the transition zone, i.e. the prostatic urethra, the anterior fibromuscular matrix and the fiber plane between the transition zone and the peripheral zone. The anterior fibromuscular matrix or fibromuscular area is mainly fibromuscular tissue.

[0011] BPH is usually diagnosed when patients complain of troublesome urination difficulties and seek drug treatment. The main symptoms of BPH are frequent urination and urgency, as well as a significant decrease in flow rate during urination. BPH may also cause urine to be retained in the bladder, which in turn may cause lower urinary tract infection (LUTI). In many cases, LUTI may then rise in the kidneys and cause chronic pyelonephritis, which may eventually lead to renal insufficiency. BPH may also cause sexual dysfunction related to sleep disorders or psychological anxiety caused by severe urination difficulties. Therefore, as the male population ages, BPH may significantly change the quality of life.

[0012] BPH is the result of an imbalance between the continuous production and natural death (apoptosis) of the glandular cells of the prostate. The overproduction of these cells leads to an increase in the size of the prostate, most notably in the transition zone that traverses the prostatic urethra.

[0013] In early cases of BPH, medications can relieve some symptoms. For example, alpha-blockers treat BPH by relaxing the smooth muscle tissue found in the prostate and bladder neck, which also allows urine to flow out of the bladder more easily. This type of medication can prove effective before glandular elements cause extreme cell growth in the prostate.

[0014] However, the more advanced stages of BPH can only be treated with surgery or minimally invasive thermal ablation devices. Various methods have been developed that utilize electrosurgery or mechanical tissue aspiration (extraction) and thermal ablation or cryoablation of intracapsular prostate tissue. In many cases, such interventions provide only transient relief, and these treatments often result in significant intraoperative discomfort and morbidity.

[0015] In a thermal ablation method, RF energy is delivered to the prostate tissue via an elongated RF needle that penetrates into multiple locations in the prostate lobe. The elongated RF needle is usually about 20 mm long, together with an insulator that penetrates into the lobe. The RF treatment produced thereby removes tissue from the prostate urethra without targeting tissue close to or parallel to the prostate urethra. The application of RF energy is usually extended by 1 to 3 minutes or longer, which allows the thermal diffusion of RF energy to remove tissue to the periphery of the capsule. This RF energy delivery method may not produce a lasting effect because smooth muscle tissue and alpha adrenergic receptors are not uniformly ablated around the prostate urethra or in the transition zone. As a result, the tissue in the prostate lobe can continue to grow and compress the urethra, thereby limiting the long-term effects of the treatment. Summary of the invention

[0016] A steam delivery system is provided, comprising: a generator unit, the generator unit including a bracket; a syringe assembly, the syringe assembly being arranged in the bracket and configured to interact with the bracket to deliver fluid at a controlled rate; an induction heating system, the induction heating system being fluidly connected to the syringe assembly and configured to receive fluid from the syringe assembly; a force sensor, the force sensor being arranged in the bracket and configured to contact the bracket and / or the syringe assembly to generate an electrical signal proportional to the force applied by the bracket and / or the syringe assembly on the force sensor; and an electronic controller, the electronic controller being configured to control the delivery of fluid and RF power to the induction heating system for generating steam, the electronic controller being further configured to calibrate the electrical signal to represent the fluid pressure within the syringe assembly, and the electronic controller being further configured to stop delivering fluid and / or RF power to the induction heating system when the fluid pressure is outside a desired fluid pressure range.

[0017] In some embodiments, the bracket is configured such that, when the syringe assembly is inserted into the bracket, the distal end of the syringe assembly is maintained at a higher height than the proximal end of the syringe assembly.

[0018] In one embodiment, the bracket is configured to purge any air from the syringe assembly during a priming step in which fluid is forced from the syringe assembly through the vapor delivery system.

[0019] In another embodiment, the carriage further comprises a piston coupled to the linear motor, wherein the piston interacts with a plunger of the syringe assembly to deliver fluid from the syringe assembly.

[0020] In some embodiments, a contact switch is activated when the syringe assembly is inserted into the bracket.

[0021] In one embodiment, the induction heating system includes an inner fluid coil surrounded by an outer conductive coil.

[0022] A method for controlling the flow of steam is provided, comprising: receiving a syringe assembly in a bracket of a generator unit; delivering fluid from the syringe assembly to an induction heating system fluidly connected to the syringe assembly at a controlled rate; measuring a force applied to a force sensor, the force sensor being disposed in the bracket and configured to contact the bracket and / or the syringe assembly during fluid delivery; and calibrating the measured force using an electronic controller to represent the fluid pressure within the syringe assembly; and stopping the delivery of fluid to the induction heating system when the fluid pressure is outside a desired fluid pressure range.

[0023] A method for treating prostate tissue is provided, comprising: inserting a vapor delivery system transurethrally into a patient to reach the patient's prostatic urethra; advancing a vapor delivery needle generally transverse to the vapor delivery system through the prostatic urethra and into a transition zone of the prostate; and delivering vapor through a distally facing vapor delivery port of the vapor delivery needle to direct the vapor distally from the device into the prostate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to better understand the invention and appreciate how it may be implemented in practice, some preferred embodiments are described below by way of non-limiting examples only with reference to the accompanying drawings, in which like reference numerals represent corresponding features throughout similar embodiments.

[0025] Figure 1 One embodiment of a steam delivery system is shown.

[0026] Figure 2A-2B An enlarged view of the distal portion of the vapor delivery system including the vapor delivery needle is shown.

[0027] Figure 2C-2D Shown is a normal prostate and an enlarged prostate treated using a steam delivery system.

[0028] Figure 3A-3B A steam delivery system including an induction heating system for producing high quality condensable steam is shown.

[0029] Figure 4 A generator unit configured to control the generation of steam in an induction heating system is shown.

[0030] Figure 5 One embodiment of a syringe assembly interacting with a generator unit is shown.

[0031] Figure 6 A cross-sectional view showing the syringe holder and syringe assembly of a generator unit.

[0032] Figure 7 is a cross-sectional view of the shaft of the steam delivery system. DETAILED DESCRIPTION

[0033] Typically, a method for treating BPH includes interstitially introducing hot steam into the prostate, wherein the steam controllably ablates prostate tissue. In clinic-based treatment, for each steam treatment (assuming multiple treatments for each prostate lobe), the method can utilize steam to apply thermal energy between 50 calories and 300 calories. The method can achieve local ablation of prostate tissue, and more specifically, the thermal energy applied by steam can be confined to ablate tissue adjacent to the urethra without damaging prostate tissue not adjacent to the urethra.

[0034] The present invention relates to the treatment of BPH, more specifically to ablating transition zone prostate tissue without ablating central or peripheral zone prostate tissue. In one embodiment, the present invention relates to treating the prostate using convective heating in an area adjacent to the prostatic urethra. The ablative treatment method is configured to target smooth muscle tissue, alpha adrenergic receptors, sympathetic nerve structures, and a depth of less than 2 cm below the vasculature parallel to the prostatic urethra between the bladder neck region and the spermatic caruncle region.

[0035] The system may include a steam delivery mechanism that delivers a steam medium, including water vapor. The system may utilize a steam source configured to provide steam having a temperature of at least 60° C.-140° C. In another embodiment, the system further includes a computer controller configured to deliver steam at intervals in the range of 1 second to 30 seconds.

[0036] In some embodiments, the system also includes a source of medicaments or other chemical agents or compounds for delivery with the vapor. These agents include, but are not limited to, anesthetics, antibiotics, or The agent may also be a sealant, adhesive, glue, super glue, etc.

[0037] Figure 1 An embodiment of a steam delivery system is shown. The steam delivery system 100 may have an elongated shaft 102 configured for insertion into the urethra of a patient and a handle portion 104 for grasping by a human hand. The steam delivery system 100 may include a steam delivery needle 106 disposed in an axis configured to extend from a distal portion of the elongated shaft 102. The steam delivery needle may extend approximately perpendicular to or transverse to the axis and may include one or more steam delivery ports configured to deliver a flow of a steam medium from the needle to the prostate tissue. The steam delivery system 100 may also include one or more triggers, buttons, levers, or actuation mechanisms 107 configured to actuate multiple functions of the system. For example, the actuation mechanism may be configured to extend / retract the steam delivery needle, and start / stop the flow of steam, aspirate, and a cooling and / or irrigation fluid such as saline.

[0038] In some embodiments, the trigger or actuating mechanism 107 can be manipulated in such a manner as to control different degrees or flow rates of steam and / or irrigating fluid. In a particular embodiment, the trigger or actuating mechanism 107 may include a first trigger configured to extend / retract a steam delivery needle, a second trigger configured to start / stop the flow of steam, and a third trigger configured to provide a cooling and / or irrigating fluid such as saline. In another embodiment, a single trigger or actuating mechanism can both extend / retract the steam delivery needle and start / stop the flow of steam. In one embodiment, a single press or depression of one of the triggers, such as a trigger that provides cooling and / or irrigating fluid, can provide a standard irrigate, while a quick double press or depression of the trigger can provide a "fast" irrigate in which the irrigating flow rate is increased compared to the standard irrigating flow rate. This feature can be useful, for example, when a physician encounters a blockage, requires additional cooling, or visibility in the urethra and / or prostate is reduced due to the accumulation of blood or other body fluids.

[0039] Fluid or irrigant source can provide fluid such as saline through the separate lumen in the shaft, to provide rinsing and cleaning to tissue during system insertion and during steam delivery to tissue. In certain embodiments, irrigant can be used to remove blood and debris from the tissue lumen to improve visibility. Irrigant can also provide cooling to the patient's urethra via direct contact of irrigant fluid with the urethra and as fluid flows out from the irrigant source via the shaft and contacts with tissue to cool the shaft of the steam delivery system. Urethral irrigating can be used during injury formation. In one embodiment, the irrigant rate can be about 80mL / min or in the range of 20 to 400mL / min. The change of irrigant rate will change the amount of tissue cooling (depth) entering the urethra and prostate, which may affect the size of the injury.

[0040] Figure 2A An enlarged view of a distal portion of a shaft of a steam delivery system 100 is shown, which includes a steam delivery needle 106 extending beyond the shaft and exposing steam delivery ports 108. The steam delivery ports 108 can be arranged in a pattern that optimizes the delivery of steam to tissue in a particular application. For example, in a system designed for the treatment of BPH, the delivery ports 108 include multiple rows of multiple steam delivery ports. In a particular embodiment, the delivery ports 108 can be spaced 120 degrees around the circumference of the needle, with one row of delivery ports being spaced 120 degrees apart, such as Figure 2B The depicted view is directed distally from the leading edge of the needle to ensure ablation of tissue adjacent the prostatic urethra. Typically, the steam delivery ports may each have a unique diameter. In one embodiment, the steam delivery ports all have the same diameter.

[0041] Figure 2C shows a normal, healthy prostate, and Figure 2D An enlarged prostate is shown treated using a steam delivery system 100. In one embodiment, the steam delivery system can be inserted into the urethra and advanced to the prostatic urethra via a transurethral approach. A steam delivery needle 106 can be advanced generally transverse to the axis of the steam delivery system and into the prostate tissue. Steam can be generated by the steam delivery system and delivered to the prostate via the steam delivery needle. As described above, the steam delivery needle can include a row of steam delivery ports directed distally from the device when the steam delivery needle extends transverse to the axis of the device. Figure 2D Steam can be delivered to the prostate through these distally facing steam delivery ports to ablate prostate tissue in the prostate that is distal to the location of the steam delivery needle. The location of the steam delivery needle and the steam delivery ports can allow ablation of transition zone tissue of the prostate that extends distally from the location of the steam delivery needle. For example, in Figure 2D In the present invention, transition zone tissue extending below the bladder muscle tissue that cannot be safely penetrated by the delivery device needle is treated.

[0042] The steam delivery system 100 may include a steam source, an aspirate source, a fluid cooling or irrigation source, a light source, and / or an electronic controller configured to control the generation and delivery of steam from the steam source through the lumen of the shaft through the steam delivery needle to the prostate tissue. In some embodiments, the electronic controller may be configured on or in the steam delivery system, while in other embodiments, the electronic controller may be configured separately from the system.

[0043] The steam source may be configured to generate a steam medium and deliver the steam medium through the steam delivery needle to ablate tissue. In one embodiment, the steam source may be a steam generator that can deliver a steam medium, such as water vapor, having a precisely controlled quality to provide a precise amount of thermal energy delivery, such as measured in calories per second. In some embodiments, the steam source may include an induction heating system configured in a steam delivery system (e.g., in a handle), in which a flowing medium is inductively heated to generate a condensable vapor, such as water vapor.

[0044] Figure 3A-3B The outer conductive coil 324 ( Figure 3B ) surrounded by the inner fluid coil 322 (in Figure 3A ) is an embodiment of an induction heating system 320. The inner fluid coil can be made of a steel tube that can be annealed. The inner fluid coil can be soldered or include a brazing rod to ensure conductivity between the coil windings. The outer conductive coil can be a conductive material, such as an electrically insulated copper stranded wire with a total diameter in the range of 18 to 22. As shown, the induction heating system 320 can be configured in a steam delivery system, such as a handle. The inlet portion 326 of the inner fluid coil 322 can receive a fluid such as sterile water from an external fluid source. As AC or RF current is applied to the outer conductive coil 324 via the electrical connection 325, the fluid can pass through the inner fluid coil 322. The current flowing in the outer conductive coil can cause current to flow in the inner fluid coil, thereby resistively heating the fluid in the inner fluid coil to produce high-quality condensable steam, which is then delivered to the steam delivery needle via the outlet portion 328.

[0045] Figure 4A generator unit 40 is shown that is configured to provide power and fluid to the induction heating system to generate steam. The generator unit can also be connected to the above-mentioned steam delivery system 100 to provide power to the system and other components that are critical to operation, such as irrigation / cooling fluids, suction, etc. The generator unit may include an electronic controller and a graphical user interface (GUI) 434 to provide operating parameters and controls to the user during steam treatment. The generator unit may include a syringe holder 430 that is suitable for holding a syringe assembly 536 to provide fluids such as sterile water to the induction heating system.

[0046] The generator unit may also include an electrical connector 432 that provides rf current to the induction heating system, electrical signals to and from the switch 107 of the steam delivery system, such as a measurement of the temperature of the induction heating system, and electrical signals to and from the controller of the steam delivery system, such as located in its electrical connector, to identify the steam delivery system, track its steam delivery record, and prevent the transitional use of a particular steam delivery system. The generator unit 40 may also include a peristaltic pump 435 that provides a cooling / rinsing fluid flow such as saline to the steam delivery system. In operation, a flexible tube 437 may pass from a sterile saline bag through the peristaltic pump and through the tubing into the steam delivery system. A guide or marking may be provided on the peristaltic pump 435 to ensure that the tube is inserted in a path that provides flow in the direction from the saline bag into the steam delivery system when the pump is normally started.

[0047] Figure 5 A syringe assembly 536 is shown that provides a precise amount of fluid, such as sterile water, to the steam delivery system 100 for conversion to steam. The syringe assembly 536 includes a syringe 537 having an exit port 541 offset from the centerline of the syringe, a luer fitting 542 that connects to a sterile water line on the steam delivery system, a plunger 538 that moves forward in the syringe to eject water and moves backward in the syringe to fill the syringe with water, and a secondary rod 540 that is removably attached to the plunger 538 to fill the syringe 537 during system setup. When the syringe 537 has been filled with fluid, the secondary rod 540 is discarded and the filled syringe 537 is inserted into the bracket of the generator unit.

[0048] Figure 6 Show Figure 4 A cross-sectional view of a syringe support 430, wherein Figure 5The syringe assembly 536 of the support 430 is inserted into the support 430. When the syringe 537 is inserted into the support 430, the contact switch 654 is enabled to ensure that the syringe is in place when the power is delivered to the steam delivery system. The state of the contact switch is sensed by the electrical lead 652. The force sensor 644 is configured in the support in such a way that it contacts and interacts with the support and / or the syringe assembly 537. When the electronic controller is ordered to deliver sterile water to the steam delivery system, the piston 642 of the support engages with the syringe plunger 538, and the linear motor attached to the piston 642 delivers sterile water from the syringe 537 to the fluid pipe connected to the induction heating system through the Luer fitting 542 at a precisely controlled rate. As the sterile water is pressed, the syringe 537 hits on the support 430, which moves freely laterally in the generator 40. The support 430 is prevented from moving forward as it hits on the force sensor 644. The microscopic lateral movement of the force sensor 644 is converted into an electrical signal proportional to the force exerted on the force sensor 644 by the bracket 430. The electrical signal is conducted to the electronic controller via the lead 648 and is calibrated as the water pressure within the syringe 537 and throughout the fluid pipes, including the inner coil of the induction heating system. The water pressure is monitored by the electronic controller of the generator unit 40, and the electronic controller can be configured to stop the delivery of RF power and fluid to the induction heating system if the fluid pressure is outside the desired pressure range, for example, if the fluid pressure is too low (e.g., due to a leak in the water line) or too high (e.g., due to a blockage in the water line).

[0049] Bracket 430 is configured to sweep any air from the fluid tubes during the priming step where water is forced out of the syringe and fills and flushes the system water lines and steam lines and then exits from the steam delivery port of the steam delivery device. Figure 6 As shown, the bracket 430 is designed to keep the distal end of the syringe 537 at a higher height than its proximal end when inserted into the bracket, and to keep the eccentric outlet port 541 of the syringe at the top of the syringe. This design forces any air in the syringe to move to the upper distal end of the syringe and leave the syringe to be swept out of the fluid tube under the influence of gravity during the priming step. Removing air from the fluid tube prevents overheating of the induction heating system and prevents loss of water volume and therefore loss of heat delivered to the tissue.

[0050] The electronic controller of the generator unit can be set to control various parameters of steam delivery, for example, the controller can be set to deliver steam medium for a selected treatment interval at a selected flow rate, a selected pressure, or a selected steam quality. More details about steam delivery systems, steam generators, and how steam and fluids are delivered to tissue can be found in U.S. Patent No. 8,273,079 and PCT Publication No. WO 2013 / 040209, which are incorporated by reference. In some embodiments, the electronic controller can also control the suction and / or cooling irrigation functions of the steam delivery system.

[0051] Figure 7 Provided Figure 1 -2 is a cross-sectional view of the elongated shaft 102 of the steam delivery system 100. The inner cavity 148 can be configured to accommodate the above and Figure 1 -2 to allow the vapor delivery needle to be advanced from the shaft during vapor delivery. The lumen 115 formed in the tube 112 may have a diameter in the range of about 2 to 5 mm to accommodate various endoscopes 118, while providing an annular space 138 to allow irrigation fluid to flow within the lumen 115 and out of the shaft into the distal urethra and bladder. The lumen 115 is sized to accommodate an endoscope or camera to provide additional observation and feedback to the physician. The endoscope or camera can provide observation of the distal end of the shaft, including observation of the vapor delivery needle when deployed. As Figure 7 As can be seen, lumen 115 is sized to provide space 138 for fluid irrigation to flow around endoscope 118. In some embodiments, annular space 138 may be a separate concentric lumen around the endoscope for irrigation fluid to flow. Annular space 138 allows irrigation fluid to flow from the vapor delivery system into the tissue and also provides cooling to the shaft as vapor is delivered from the vapor delivery needle (disposed in lumen 148) into the tissue. Figure 7 The material 144 in can conduct heat from the steam delivery needle to the irrigation / cooling fluid flowing in the annular space 138, or alternatively, can conduct cold from the irrigation / cooling fluid to the steam delivery needle to prevent overheating of the patient (specifically, the urethra) during steam therapy.

[0052] Although specific embodiments of the present invention have been described in detail above, it should be understood that this description is for illustrative purposes only, and the above description of the present invention is not exhaustive. Specific features of the present invention are shown in some figures and not in other figures, which is only for convenience, and any feature can be combined with another feature according to the present invention. Various modifications and alternatives will be apparent to those of ordinary skill in the art. These alternatives and variations are intended to be covered within the scope of the claims. The specific features set forth in the dependent claims can be combined and fall within the scope of the present invention. The present invention also includes multiple implementations, just as multiple dependent claims are alternatively written in the format of multiple dependent claims citing other independent claims.

Claims

1. A steam delivery system comprising: Generator unit, a bracket, the bracket being arranged in the generator unit; a syringe assembly, the syringe assembly being disposed on the support; a force sensor disposed in the bracket and configured to contact the bracket and / or the syringe assembly to generate an electrical signal indicative of a lateral force exerted by the bracket and / or the syringe assembly on the force sensor in a lateral direction, wherein the lateral direction is a direction perpendicular to a longitudinal axis of the syringe assembly; and An electronic controller is configured to receive the electrical signal.

2. The steam delivery system of claim 1, wherein: The electronic controller is also configured to calibrate the electrical signal to be representative of fluid pressure within the syringe assembly.

3. The steam delivery system of claim 2, wherein: The electronic controller is also configured to stop delivering fluid when the pressure is outside of a desired fluid pressure range.

4. The system according to claim 1, wherein: At least a portion of the support is free to move laterally within the generator unit.

5. The system according to claim 1, wherein: The carriage also includes a piston coupled to the linear motor, wherein the piston is configured to interact with a plunger of the syringe assembly to deliver fluid from the syringe assembly.

6. The system according to claim 5, wherein: Interaction of the plunger with the syringe assembly causes the bracket to exert a lateral force on the force sensor.

7. The system according to claim 1, wherein: The support is configured such that the distal end of the syringe assembly is held at a higher height than the proximal end of the syringe assembly.

8. The system according to claim 1, wherein: The bracket is configured to sweep any air from the syringe assembly during the priming step.

9. The system according to claim 1, wherein: A contact switch is activated by contact between the barrel of the syringe assembly and the bracket.

10. The system according to claim 1, wherein: The force sensor is arranged between the support and the generator.

11. The system according to claim 1, wherein: The barrel of the syringe assembly directly contacts the support.

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