External vacuum tissue expander with non-stick rim

Abstract

To provide a tissue expander that can prevent excessive pressure that collapses capillary circulation and reduce shear stress generated at skin junctions. The tissue expander includes a shell, an opening in the shell that communicates with an external vacuum source for applying a vacuum within the shell to provide a distraction force to expand tissue, and a rim coupled to the shell and adapted to contact the patient's skin, the rim being non-fixedly attached to the patient's skin and adapted to move laterally outwardly relative to the shell under application of vacuum.

Description

[Technical Field]

[0001] This application relates to an external vacuum expander, and more particularly to an external vacuum tissue expander having a support rim for reducing shear stress.

[0002] [Cross-reference of related applications] This application claims priority to U.S. Provisional Patent Application No. 63 / 122,016, filed on 7 December 2020, the entire disclosure of which is incorporated herein by reference. [Background technology]

[0003] It is an established biological phenomenon that sustained, gentle tension is a natural stimulus for tissue growth. During childhood, growth occurs thanks to the tension generated by the epiphyseal growth plate, which lengthens bones. Internal expansion tissue expanders and Ilizarov bone stretchers are examples of widely used medical devices that expand tissue based on this principle. However, these medical devices require invasive surgical procedures that are prone to complications. Therefore, there is a social need for an external, non-invasive, yet safe, practical, and easy-to-use tissue stretching device.

[0004] Cosmetic breast augmentation and breast reconstruction after mastectomy are two of the most common applications of this type of non-invasive tissue expansion. Dating back to the 1800s, a great many vacuum-based breast augmentation devices have attempted to achieve this goal. While some have been sold for many years, they were essentially all considered novelty items, and none have demonstrated their effectiveness in scientific clinical studies, because none could be consistently applied over the period required to induce substantial tissue growth.

[0005] The Brava device, invented and designed by the inventors of the present invention and disclosed in U.S. patents such as U.S. Patents 6,641,527, 6,500,112, 6,478,656, 5,676,634, 5,695,445, and 5,662,583, is the only device known to the inventors to have scientifically proven efficacy reviewed by the FDA. The Brava device has succeeded in inducing permanent tissue growth because the inventors identified the biomechanical constraints associated with maintaining a vacuum over the breast for extended periods and applied biomedical engineering principles to overcome these constraints. While the Brava device represents a substantial improvement over the prior art, it has not yet replaced breast implants because patient adherence to medication remains a significant hurdle. The Brava device is impractical and difficult to use 24 / 7 for the months required to achieve substantial tissue growth. In addition to being bulky and cumbersome, the Brava device has several other limitations that have not been adequately addressed despite being in use for over 25 years. Therefore, the inventors recognize the need for improvement of the Brava device.

[0006] Achieving breast augmentation involves many challenges related to maintaining a vacuum that sustainably induces stretching force on the breast over a long period of time. Three of these challenges are: 1) Maintaining a vacuum by avoiding air leaks, despite the complex surface contour of the torso, the magnitude of individual differences, and significant changes in surface topography caused by torso and shoulder movements. 2) To prevent excessive pressure that could disrupt capillary circulation and lead to pressure ulcers, the stretching force applied to the breast is balanced by the reaction force applied to the rim of the external vacuum expander (shell / dome) that comes into contact with the surrounding skin. 3) Reduce the shear stress generated at the junction between the taut skin inside the vacuum shell (dome) and the skin that is firmly held and fixed by the inner lip of the shell's rim. These shear forces, concentrated on the inner lip of the rim, are the main cause of dermatitis, blister formation, and ulcer formation.

[0007] The inventor's conventional Brava device was a soft silicone gel airbag that conformed to the complex contours of the chest wall and absorbed to some extent the various surface microstructures associated with normal activities, attempting to solve Problem 1). To prevent air leakage, the bottom of this airbag included an adhesive layer that sealed the airbag to the skin. However, that adhesive layer tended to wear out with daily use. When the adhesive layer deteriorated, air leakage occurred, and thus the Brava device provided only a short-term solution to the problem of air leakage.

[0008] Recognizing that an external pressure exceeding 20 mmHg occludes capillary circulation (as described in U.S. Patent No. 6,500,112, 20 mmHg being the maximum pressure that can be safely withstood for a long time under the rim), the Brava device attempted to solve the balance adjustment of the reaction force (Problem 2) by having a surface contact area of the rim equal to the surface area of the dome opening to which the vacuum pressure is applied.

[0009] The Brava device attempted to solve the shear stress (Problem #3) by providing a contact rim that disperses the shear by supplementing some of the peripheral skin. The larger the opening, and thus the greater the amount of tissue under tension, the greater the shear stress. · Shear stress = τ = Force / Shear area · Force = P ressure × Assume surface area · Approximate the opening as a circle, surface area S = πR 2 · Force = P ressure × πR 2 · Shear area = Circumference (2πR) × Tissue thickness (T hickness ) · Shear stress = τ = Force / Shear area = P × πR 2 / (2πR × T) = P ressure × R / T hickness · P ressure and T hickness If they are constant, there is a linear relationship between the radius and the shear stress. The larger the radius, the greater the shear stress.

[0010] For these reasons, small suction cups, nipple dilators, and breastfeeding devices (up to 3 to 6 cm) have little need to address this problem. The skin around the breast margin (at least 10-12 cm in opening diameter) fixed by the rigid rim is subjected to a considerable amount of lateral inward stress. Before the Brava device, no prior art addressed this problem, which is likely why none of these devices were adopted in the medical field. Because the gel rim of the Brava device has an adhesive base, the gel rim adhering to the skin needs to flex considerably to replenish the amount of skin necessary to distribute the shear stress. This proves to be the most difficult problem to solve. For the flexing arc to supply the required amount of inward replenishment, the gel rim needed to be at least 4 to 5 cm high. It also needed to be very well fitted, offering almost no resistance to the inward roll. This was due to the bulkiness, height, weight, and premature wear of the constantly flexing silicone gel air bladder.

[0011] None of the more than 50 prior art patented breast augmentation devices possess features that address the aforementioned problems / challenges. In fact, none of them, except for the Brava device, address reaction forces and shear forces, and even the Brava device has several limitations.

[0012] Suction pads, while sometimes having rubber rims, often lack the necessary configuration to meet specific durometer and elastic requirements, and thus fail to address the challenges of reaction / shear forces. Furthermore, suction pads often lack sufficient indentation and width. Suction cups also differ significantly from breast augmentation devices. Their shear stress is minimal compared to breast augmentation devices that are an order of magnitude larger. Moreover, most suction cups are passive, typically lacking an external vacuum pump, with the vacuum source being the contraction force of the rubber rim itself. Additionally, suction cups are often made of natural rubber, which has a high incidence of allergies, limiting their use in medical devices.

[0013] U.S. Patent No. 10,603,161 discloses an apparatus and method for nipple and mammography. This apparatus uses adhesive force to hold the mold in place. The rim design is tapered and lacks sufficient concavity. The apparatus of the '161 patent does not have a method for distributing greater shear forces that would likely cause skin blisters. The breast has a larger surface area than the nipple, so it deforms more and the force on the periphery is greater for the same pressure. The amount of stretching (tension) of the nipple skin is minimal compared to the breast, so the shear force is smaller on the nipple.

[0014] U.S. Patent No. 10,433,947 (by the same inventors as the present invention) discloses a method and apparatus for tissue expansion. This patent describes a splint for holding an inflated / pre-expanded breast in place as an alternative to expansion by external vacuum. The patent states, "Another method of mechanically bonding a splint to the skin is surface tension. Surface tension is a naturally occurring means by which the body binds together tissues that need to remain mechanically bonded but still need to slide to avoid shear forces. This is how an expanding rib cage expands by transmitting the mechanical force of inhalation to the soft, sponge-like lungs, and furthermore, how the loops of the intestines slide through one loop while being held together." However, surface tension is used to apply tensile expansion forces to tissue as an alternative to adhesives, replacing the need for vacuum or conventional adhesives.

[0015] U.S. Patent No. 5,676,634 (by the same inventors as the present invention) discloses a method and apparatus for expanding soft tissue with balanced force. This patent discusses a rim having a surface area sized to prevent excessive contact pressure on the skin. This patent does not address shear.

[0016] U.S. Patent No. 6,500,112 (by the same inventors as the present invention) discloses a vacuum dome having a support rim and a rim cushion. This patent describes minimizing shear force by providing a joint between the dome and the skin that allows inward displacement of the contact surface. This reduces the strain dL / L on the skin, where dL is the same but L is larger. The contact surface is no longer fixed by a rigid dome, and the flexible interface allows the skin to move more freely with less strain, lower stress, and lower shear force. However, this device still does not fully satisfy the aforementioned problems.

[0017] U.S. Patent No. 9,498,565 discloses a breastfeeding device. Embodiments of the disclosed device include a bra insert that holds the device in place. Some embodiments include a shoulder harness and a torso harness, or other band-hanging fabric or mechanism that holds the device in place to enable hands-free compression. Furthermore, a sticky fabric that utilizes van der Waals forces on the front of the soft structure 1 in Figures 3A and 4A to hold the device in place is disclosed, such as Geckskin® (University of Massachusetts Amherst, Amherst, Massachusetts, USA). In some embodiments of this patent, a lubrication system is described to prevent chafing after repeated use. Also disclosed is a thick lip-shaped structure along the flange of an elliptical opening, which may include small holes that allow lubricant to slowly leak onto the user's breast. As described, this lubricant can also function as a source of wet adhesion to ensure proper sealing between the device and the user's breast. Some embodiments include lubrication applied by the user before use, or may not use lubrication. The use of lubricants as a means of preventing chafing after repeated use is disclosed. This is different from the use of lubricants to reduce shear force. Breast pumps that express breast milk use intermittent vacuum to mimic a nursing baby. Friction from nipple pumps is due to friction as the nipple is sucked in and out, not due to shear force. Nipple creams for breast pumps are common. These nipple aspirators have a limited opening around the areola, minimizing the shear stress they experience. (https: / / www.amazon.com / Motherlove-Certified-Organic-Cracked-Nursing / dp / B0007CQ726 / &tag=diapersnet-20)

[0018] As can be understood, the above-described prior art devices cannot address the drawbacks / issues enumerated above, and some do not even recognize or are not related to the importance of shear force. Therefore, there is a need for a vacuum expander for tissue expansion that can effectively prevent air leakage to maintain a vacuum, prevent excessive pressure that is thought to disrupt capillary circulation, and reduce shear stress generated at the skin junctions. Also, the device needs to be comfortable even when worn for a long time, minimize dermatitis and blisters, and be further concealable and wearable comfortably like a normal padded bra. Such a device can improve breast expansion / enlargement and expansion / enlargement of other body tissues. Furthermore, such a device can also be used for breast reconstruction.

Prior Art Documents

Patent Documents

[0019]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Summary of the Invention

Means for Solving the Problems

[0020] The present invention solves the problems and defects of the prior art. The present invention provides a comfortably wearable dome-shaped (or other shaped) device having a special rim that contacts body tissue and utilizes vacuum for tissue expansion, for example, breast tissue expansion. The expander device of the present invention, also referred to herein as a vacuum expander or tissue expander, 1) effectively maintains a vacuum by preventing air leakage, 2) balances the stretching force applied to the breast with the reaction force exerted by the rim of the external vacuum expander that contacts the surrounding skin in order to 1) effectively maintain a vacuum by preventing air leakage, 2) prevent excessive pressure that would disrupt capillary circulation and lead to ulceration and compression ulceration, and 3) reduces the shear stress generated at the junction between the taut skin inside the vacuum shell and the skin firmly pressed and fixed by the inner rim of the rim in order to reduce dermatitis, blistering, and ulcer formation caused by excessive shear force concentrated on the inner lip of the rim.

[0021] It should be understood that the device of the present invention can perform breast enlargement / expansion, as well as other body tissue enlargement, with minimal trauma and without failure.

[0022] To maintain an airtight seal, i.e., to maintain a vacuum, the apparatus of the present invention replaces the adhesive gel air bladder of the Brava apparatus with a deeply recessed, wide, tapered, soft rubber skirt that flexes and expands under the influence of a downward vacuum force. This increases the surface contact area and improves sealing. Furthermore, to maintain an airtight seal, the recessed configuration of the skirt's edge ensures that the feather-like flared periphery engages downward with and supports the surface contour of the torso. In addition, this flexible, adaptable soft rubber skirt can accommodate a considerable amount of body movement without losing the vacuum seal.

[0023] Furthermore, the device of the present invention effectively balances tensile and reaction forces. When the vacuum pressure is increased, the concave flexible rubber rim of the device flexes and expands outward to increase surface contact, resulting in a reduction of counterpressure on the skin. This property of the concave tapered flexible rubber rim (sole), which increases surface contact as the downward force increases, balances the forces to keep skin pressure below harmful levels.

[0024] The device of the present invention completely solves the problem of shear stress. Since the soft rubber rim maintains the vacuum seal by faithfully supporting the body's contours, no adhesive layer is needed. On the contrary, the device functions best when a lubricant is present, providing frictionless sliding between the skin and the rubber rim (skirt) that opens to envelop the body. Since the contact surface is no longer adhered to and fixed to the rim, the skin moves freely, and tension can replenish as much surrounding skin as necessary to dissipate harmful shear stress. With this almost free replenishment of tissue, tensile, force, and shear stresses are reduced. Thus, the vacuum expander of the present invention solves the shear stress problem by operating in the opposite manner to vacuum expanders of the prior art. While the prior art devices focused on fixing the rim position using adhesive, the present invention actually "releases" the rim to facilitate its movement / sliding. Therefore, the non-adhesive (e.g., lubricated) joint of the rim according to the present invention allows the rim to expand under the influence of vacuum in order to increase the contact surface and reduce pressure and to eliminate shear forces by allowing the surrounding tissue to replenish freely.

[0025] According to one aspect of the present invention, a tissue expander is provided comprising a shell, an opening in the shell communicating with an external vacuum source to apply a vacuum within the shell to impart an tensile force that expands tissue, and a rim coupled to the shell and adapted to contact the patient's skin. The rim is non-fixed to the patient's skin and moves laterally outward relative to the shell under the application of vacuum.

[0026] In some embodiments, the shell is dome-shaped.

[0027] In some embodiments, the rim is made of rubber and has a lubricating layer on its bottom surface to allow it to slide over the skin, thereby reducing shear stress between the rim and the skin contact surface. In other embodiments, the rim has a lubricant that reduces frictional contact with the skin in order to allow the rim to slide. In preferred embodiments, the rim is made of synthetic rubber and has a low durometer.

[0028] In a preferred embodiment, the rim has a non-stick, non-adherent tissue-contacting underside.

[0029] In some embodiments, the rim has a concave tapered portion that flexes and opens to form a skirt that spreads laterally. In a preferred embodiment, when downward pressure is applied by vacuum, the rim conforms to the contour of the patient's body, and the rim flexes to increase the contact surface with the skin and prevent an increase in counterpressure against the skin.

[0030] In some embodiments, the rim has a downward-facing feather-like periphery to wrap around a portion of the torso and interlock with it. Other features / aspects that can be incorporated into some embodiments of the rim of the present invention include one or more of the following: a) a flexible rim that is thicker and more pliable than the proximal portion of the rim; b) a tapered and inwardly curved axially less than 20 degrees from the vertical; c) an asymmetrical shape having a narrower inner skirt and a more curved lateral inward-facing skirt that provides a deeper concave surface on the lateral side and a longer length than the inner side to wrap around the contour of the body; and / or d) fin pockets into which thin-walled ribs or fins of appropriate curvature and durometer can be inserted to help support the lateral contour of the torso.

[0031] In some embodiments, the rim has a coupling mechanism for the release attachment of domes (or shells) so that a dome of a first size can be removed from the rim and a dome of a second size can be attached to the rim. In these embodiments, domes (shells) of various sizes can be selectively coupled to the rim. In other embodiments, two or more domes are permanently attached to the rim, and the two or more domes are progressively deeper in size.

[0032] According to another aspect of the present invention, a tissue expander is provided comprising a shell, an opening in the shell communicating with an external vacuum source to impart an tensile force to expand tissue by applying a vacuum into the shell, and a rim coupled to the shell and adapted to contact the patient's skin. The rim has a concave underside which deforms to flex outward to invert into a convex shape when a vacuum is applied. That is, the lower portion of the rim changes from concave to convex, while in some embodiments, the periphery, particularly the lateral side, remains concave to maintain a seal.

[0033] In some embodiments, the rim has a tapered surface that gradually decreases in thickness toward the periphery to allow for greater flexing than the thicker portion of the rim (closer to the dome), resulting in a thinner, more flexible edge. Other features that can be incorporated into embodiments of the rim of the present invention include one or more of the following: a) a taper to a feather thickness forming a feathered edge; b) the lateral side of the rim having a longer and deeper concave surface than the inner side of the rim; c) an inward curvature that slopes downward from the horizontal plane to enhance the bite with the patient's body; and / or d) an interlocking design that allows the inner edges of both rims to overlap without leaving folds in the air passage that could cause vacuum loss. In some embodiments, the rim is made of a low-durometer rubber material. In some embodiments, the rim is made of synthetic rubber materials with different durometers, and the periphery has a lower durometer.

[0034] In some embodiments, when a downward pressure is applied, the reaction force between the rim and the skin is uniformly distributed over the skin contact area. In some embodiments, as the vacuum pressure increases, the rim flexes and expands, increasing the contact area with the skin and reducing the counterpressure on the skin.

[0035] According to another aspect of the present invention, a bra is provided, the bra comprising: a) a first shell having a first opening; b) a second opening; and c) a first rim extending laterally outward, wherein the first opening is sized and configured to receive the first shell and / or the first rim, and the first rim is non-fixedly positionable in contact with the patient's skin; and d) a second shell having a second rim extending laterally outward, wherein the second shell opening is sized and configured to receive the first shell and / or the first rim, and the second rim is non-fixedly positionable in contact with the patient's skin. In some embodiments, a stretching force is applied to the patient's skin within the first and second shells, during which the first and second rims slide laterally outward while maintaining contact with the skin.

[0036] In some embodiments, the rim has a concave underside that deforms and inverts into a convex surface when a vacuum is applied.

[0037] In some embodiments, the tensile force is applied by an external vacuum communicating with the shell, and in other embodiments, the tensile force is applied by the elastic contraction force of the shell and / or rim.

[0038] The bra may include reinforcing bands to connect the bra to the rim, and / or reinforcing straps to keep the feathery edges of the rim in firm contact with the skin to ensure a vacuum seal.

[0039] Another aspect of the present invention provides a method for reducing shear stress in a tissue-expanding device. The method involves positioning a device having a shell and a rim extending from the shell configured to contact a patient's body, wherein the rim is positioned non-adhesively to the body and, when an tensile force is applied within the shell, expands laterally outward relative to the shell, so that shear stress is reduced at the junction between the taut skin within the shell and the skin firmly pressed and fixed by the rim.

[0040] In some embodiments, the tensile force is applied by the elastic contraction force of the rim.

[0041] In some embodiments, the tensile force is applied by applying a vacuum within the shell. A portable vacuum pump may be provided in communication with the interior of the shell to apply the vacuum. A pressure control mechanism may be provided to control the vacuum pressure within the shell. In some embodiments, the pressure control mechanism includes a manual pump with a pressure relief valve to prevent the vacuum pressure from reaching harmful levels. In some embodiments, as the vacuum pressure increases, the rim expands and flexes more, increasing the area in contact with the skin and reducing the counterpressure on the skin.

[0042] Preferred embodiments are described below in detail with reference to the drawings so that those skilled in the art can more easily understand how to manufacture and use the surgical devices disclosed herein. [Brief explanation of the drawing]

[0043] [Figure 1A] A schematic diagram of the forces (biophysical) generated by an external vacuum expander is shown. [Figure 1B] A schematic diagram of the forces (biophysical) generated by an external vacuum expander is shown. [Figure 1C] This is a schematic diagram of the shear effect during use of an external vacuum expander of prior art. [Figure 2A] The photograph shows how a vacuum applied to a prior art device with an adhesive gel rim compresses the breast like a vise as the rim flexes inward to dissipate shear stress, and also shows the state without a vacuum. [Figure 2B] This photograph shows how a vacuum applied to a prior art device with an adhesive gel rim compresses the breast like a vise as the rim bends inward to dissipate shear stress, illustrating the state with a vacuum. [Figure 2C] Figure 2A is a photograph illustrating how the limited inward deflection of the adhesive rim of prior art devices, such as the one shown, causes skin damage due to shear forces. [Figure 3A] This document presents an exemplary example of the shear effect in an embodiment of a prior art miniature vacuum expander dome (shell). [Figure 3B] This document presents an exemplary example of the shear effect in an embodiment of a prior art large vacuum expander dome (shell). [Figure 4] This is a schematic side view of an external vacuum expander according to an embodiment of the present invention, shown in contact with breast tissue, with arrows indicating shear forces dissipated due to dome sliding. [Figures 5A-5C] Figure 5A is a schematic side view of a vacuum expander according to an embodiment of the present invention, showing a non-contact state; Figure 5B is a schematic side view of a vacuum expander according to an embodiment of the present invention, showing adaptation to low pressure; and Figure 5C is a schematic side view of a vacuum expander according to an embodiment of the present invention, showing adaptation to full pressure. [Figure 6A] This is a perspective view of an embodiment of the vacuum expander of the present invention, showing the rim skirt of the dome (shell) that expands to adapt to the complex convex contour of the body. [Figure 6B] This is a perspective view of an embodiment of the vacuum expander of the present invention, showing the rim skirt of the dome (shell) that expands to adapt to the complex convex contour of the body. [Figure 6C] Figure 6B shows how the skirt wraps around the convex surface of the fuselage. [Figure 6D] This is a photograph showing the dome of the present invention being pushed down onto a flat surface. [Figure 6E] This photograph shows the rim skirt expanding and its periphery stretched. [Figure 6F] This is a series of photographs showing various embodiments of the asymmetric dome of the present invention. [Figure 7A-7C]Figure 7A shows a schematic side view of the rim of a vacuum expander according to an embodiment of the present invention, with the dome attached to the rim and the rim in a non-contact state. Figure 7B shows a schematic side view of the rim of a vacuum expander according to an embodiment of the present invention, with the dome attached to the rim and the rim having a curvature that gradually expands and curves inward at low pressure. Figure 7C shows a schematic side view of the rim of a vacuum expander according to an embodiment of the present invention, with the dome attached to the rim and the rim fully open at high pressure. [Figure 8] This figure is similar to Figure 7A, showing another depth of the dome shell attached to the rim, and also presents an alternative rim design with an additional inwardly oriented, thin-walled, flexible rim that increases the contact area with the skin to improve vacuum sealing. [Figure 9A] This photograph shows how the rim of the vacuum expander in an embodiment of the present invention is shaped to wrap around the chest and embrace the skin surface due to the tapered fins. [Figure 9B] This photograph shows how the rim of the vacuum expander in an embodiment of the present invention is shaped to wrap around the chest and embrace the skin surface due to the tapered fins. [Figure 9C] Figure 9A shows a photograph illustrating how, without the fins of the device, the thin, feather-like edges tend to curl up due to peripheral tension, and the edges do not wrap around the contour of the chest. [Figure 9D] Figure 9A shows a photograph illustrating how, without the fins of the device, the thin, feather-like edges tend to curl up due to peripheral tension, and the edges do not wrap around the contour of the chest. [Figure 10] This is a schematic diagram of an alternative embodiment of the vacuum expander of the present invention, which has one embodiment of a fastening mechanism for securing a flexible rim to a replaceable, more rigid shell. [Figure 11] This is a schematic diagram of an alternative embodiment of the vacuum expander of the present invention, which has an inner lip and a pocket / slit for inserting a fin that can be reshaped to follow the convex surface of the chest contour. [Figure 12]This is a schematic diagram of an alternative embodiment of the vacuum expander of the present invention, which has thin-walled tapered fins with arched notches between the fins to prevent winding up and abduction. [Figure 13] This is a schematic diagram of an alternative embodiment of the vacuum expander of the present invention, having a shell dome of various depths with an invariant base for interacting with a rim skirt. [Figure 14A] This shows a mastectomy patient wearing a bra incorporating an embodiment of the vacuum expander of the present invention and holding a small pump. [Figure 14B] This shows a mastectomy patient wearing a bra incorporating an embodiment of the vacuum expander of the present invention and holding a small pump. [Figure 14C] This shows a cosmetic surgery patient wearing a bra incorporating an embodiment of the vacuum expander of the present invention. [Figure 14D] This shows a cosmetic surgery patient wearing a bra incorporating an embodiment of the vacuum expander of the present invention. [Modes for carrying out the invention]

[0044] This invention addresses the three problems / issues listed in the "Background Art" section, namely, 1) Maintaining a vacuum inside the dome (shell) by avoiding air leaks, despite the complex surface contour of the torso, the large degree of individual variation, and significant changes in surface topography caused by torso and shoulder movements. 2) To prevent excessive pressure that could disrupt capillary circulation and lead to pressure ulcers, the stretching force applied to the breast is balanced with the reaction force applied to the rim of the external vacuum expander that is in contact with the surrounding skin (the arrows in Figure 1A show the relationship between the stretching force and reaction force due to the vacuum, and the area and pressure under the dome). 3) To reduce the shear stress generated at the junction between the taut skin inside the vacuum shell (dome) and the skin firmly pressed and secured by the inner lip of the shell's rim (this reduces dermatitis, blistering, and ulcer formation caused by shear forces concentrated on the inner lip of the rim), To provide solutions to all of these issues, we utilize advances in materials technology, such as silicone rubber, urethane, and other synthetic rubber material technologies.

[0045] Solutions to each of these problems / challenges (hereinafter referred to as #1, #2, and #3) are described in detail below. This is achieved by a vacuum expander having a dome (shell) or other molded device mounted on a uniquely designed and configured rim (also referred to herein as a skirt) that interacts with the skin independently and functions in a different manner from prior art vacuum expanders and current vacuum expanders. It should be noted that a solution to any one of the three problems / challenges described above will result in an improvement over prior art devices and current devices, such that the present invention in some embodiments can address only one or two of the problems / challenges, or all three.

[0046] The tissue expander of the present invention uses pressure from an external vacuum source or the contraction force of a rubber rim or semi-rigid shell to impart an extensor force that can expand tissue. The device comprises a shell (hereinafter also referred to as a dome when a dome is formed) that forms a rigid portion for tissue expansion, and a softer rim that contacts the tissue to function as a joint between the dome and the tissue. The rim may have a coupling mechanism for permanent or removable attachment to the dome. A pump, sensor, and servo mechanism control the vacuum pressure within the dome, and the pump communicates with the interior of the dome via a tube extending from the pump to or into the opening of the dome. Alternatively, if the contraction force of a rubber rim is utilized to generate a vacuum, an adjustable pressure release valve may be included to prevent the accumulation of higher vacuum pressures that could damage the tissue.

[0047] Prior art teaches the use of adhesive to fix vacuum expanders to the skin. However, after many years of research, the inventors have found that the use of adhesive causes various problems, including those listed above. The inventors have found that the opposite effect—that is, allowing the skin beneath the vacuum expander to slide or move rather than being fixed with adhesive to fix its movement—actually results in a significant reduction in shear stress and a substantial reduction in skin damage due to excessive shear force. Therefore, the expander of the present invention, which is attached to the skin non-fixed / non-adherent as developed by the inventors, is not intended in the teachings of the prior art and actually operates in the opposite way to those teachings. Furthermore, the inventors have recognized the limitations of current rim configurations and have discovered unique features that improve the fit of the rim to the wearer's body.

[0048] This invention provides excellent results for tissue expansion using vacuum. Such tissue expansion will be described below in relation to breast expansion / enlargement, but it can also be used for the expansion / enlargement of other body tissues.

[0049] To maintain an airtight seal (Problem #1) and balance the tensile force with the reaction force (Problem #2), some embodiments of the present invention replace the prior art adhesive gel air bag with a deep concave, wide, tapered, soft, low-durometer rim that forms a skirt that flexes to open and expand under the influence of a downward vacuum force. This increases the surface contact area and improves the seal. This can be seen by referring to Figures 5A to 5C. Figure 5A shows the vacuum expander when not in contact with tissue (the skirt (rim) 102 is separated from the tissue). When pressure is applied, the expander conforms to / matches the complex surface contours of the body and absorbs body movements by flexing and bending with increasing force to increase surface contact. This conformability is evident when partial (mild) pressure is applied to the expander 100, the skirt 102 expands laterally outward to conform to the skin surface S (Figure 5B), and when full pressure is applied, the contact surface area increases as shown in Figure 5C. The lower surface 102a of the rim (skirt) 102 engages well with the skin as its shape changes, as shown in Figure 5C. Therefore, with increasing downward force, the rim of the device flexes (i.e., moves laterally outward) to increase surface contact and prevent an increase in counterpression pressure on the surrounding skin, i.e., to maintain the pressure on the skin at a safe level. (Note that the rubber rim slides on the skin not by sticking, but due to a lubricating layer as detailed below). Furthermore, the deep concave design / configuration of the skirt / rim forces the feather-like flared periphery to interlock downwards to maintain an airtight seal and support the complex convex contour of the torso. In addition, this flexible, adaptable soft rubber skirt can accommodate a considerable range of body movements without losing the vacuum seal.

[0050] The comparison in Figures 6A and 6B illustrates, for illustrative purposes, the expansion (lateral outward spreading) of the skirt 102 when the dome 104 of the device 100 is pushed downward on a flat surface by increasing vacuum pressure. The skirt 102 is designed to bend and expand (bend outward) as the vacuum pressure increases (as a downward force is applied), thereby increasing surface contact. That is, when the peripheral rubber rim is applied to the convex surface of the chest, it is subjected to two forces: an inward tensile force due to circumferential stretching and a downward bend due to resistance to bending (see arrow in Figure 6C). These forces combine to ensure that the skirt edge 102b wraps around the chest, embraces the torso, and firmly supports the complex surface contour. The inward curvature 102b of the skirt periphery (see Figures 5C and 6B) improves the interlocking as the periphery stretches. Figure 6A shows the skirt 102 extending from the dome 104 of the expander 100 before pressure is applied, and Figure 6B shows the skirt 102 after pressure is applied and it has been expanded, with the diameter / cross dimension D2 of the skirt 102 being larger than the diameter / cross dimension D1 in Figure 6A. Furthermore, a comparison of Figures 6D and 6E shows that when the dome is pushed downwards onto a flat surface, the rim skirt expands and its periphery is stretched.

[0051] Considering the elasticity, thickness, and taper angle of the rubber material, the mechanical properties of the rim are designed so that it expands and widens in response to increasing downward force, thereby increasing the skin contact area to maintain the surface counterpressure below harmful levels. Furthermore, this design prevents pressure spots and ensures a uniform pressure distribution along the contact area. In other words, the thinner, more flexible edges flex more than the thicker proximal portions, so that a relatively constant downward force is maintained on the tissue along the width of the rim.

[0052] Figure 6F shows the configuration of the device 100 from various angles, including the side, bottom, and top views. The preferred configuration of the rim joint is a skirt, as shown in Figures 5A to 5C and 7A to 7C. The skirt is long (e.g., about 2 cm to 5 cm inward, and about 4 cm to 9 cm laterally), but other dimensions are intended, tapered, curved inward, and deeply concave (e.g., its axis is less than 15° from the vertical axis X, but other angles are also intended). It has a non-stick, non-adhesive, and very low durometer rubber sole, which is designed to support the contour of the body and further flex and spread outward to increase surface contact with increasing pressure.

[0053] As shown in the figure, the rim is tapered in thickness, with the maximum thickness at the top 107 (near the dome 104 where the rim joins in region 108), for example, about 1 inch, and tapering to a maximum of several millimeters at the periphery. In some embodiments, the rim is tapered in region 114 to the thickness of a feather having a feather-like edge 116. An inner, thin-walled, highly flexible feather 112 may be provided for additional sealing. This thin-walled, feather-like inner lip 112 results in a wider, better seal. Other thicknesses along various regions of the rim are intended to absorb movement, prevent pressure points, and distribute counterpressure against the skin more evenly.

[0054] In a preferred embodiment, the rim is of an asymmetrical design (see, for example, Figure 6F), having a narrower (shorter) inner skirt that covers the sternum and a longer skirt that curves inward laterally to wrap around the torso. Exemplary, the rim may have a longer flange with a maximum length of approximately 3 inches on the lateral side and a minimum length of approximately 1 inch on the inner side, but other dimensions are also contemplated. This asymmetrical design has a deeper concave surface to wrap around the contours of the body, resulting in a longer lateral side than the inner side. It should be noted that the thickness and length do not need to be uniform along the circumference, as there are generally left and right sides. At rest (Figure 7A), i.e., when the inner surface 102a is not in contact with the skin, the skirt rim 102 has a concave or straight downward curve in cross-section, and the inward curvature 114 pushes the skirt rim 102 further downward, and as the periphery extends, it engages with the curvature of the torso. This concave surface becomes convex where the directional force is greatest beneath the rigider rim, and then, if necessary to support the contour of the body, it flares out in a feather-like manner to maintain some concavity at the very edge. The rim is angled sharply downward from the horizontal plane to form a long, skirt-like rim. The downward angle can be constant or variable. The downward angle can typically vary along the periphery. In a preferred embodiment, the angle X from the horizontal plane is 45 to 85 degrees (or 45 to 5 degrees from the vertical), but other angles are also intended to result in greater concave depth. The junction between the skirt and the rigider dome is designed so that the angle X increases inward, shorter (narrower) to keep the pressure uniform around the entire circumference of the periphery, as the vacuum pressure increases and the downward force increases, causing the angle X to widen from near the vertical so that the angle X becomes more horizontal. The lower part of the rim changes from concave to convex, while the periphery, particularly the lateral side, may need to remain concave to maintain the seal, as can be seen in Figure 6C. In other words, angle X changes from nearly vertical to 60 degrees or nearly horizontal when pressure is applied.Therefore, when downward pressure is applied, the downward force from the dome is counteracted by the skin, and the rim can remain concave at its lateral periphery, expanding from concave to convex or nearly flat at the point of maximum pressure, and the reaction force between the skirt and the tissue is evenly distributed across the skin contact area to avoid pressure points where the pressure increases.

[0055] The deep concave rim is preferably made of a low-durometer synthetic rubber material such as silicone or a newer formulation of urethane. As pressure increases, the rim flexes more to increase the contact area and reduce the counterpression acting on the skin. Furthermore, the rim is designed so that the applied vacuum does not bend the rim inward and draw it into the dome section. (This reduces the opening of the expanded surface). In preferred embodiments, low-durometer (anywhere on the entire Shore 00 scale) or low-Shore A scale (less than 25 Shore A) rubber, preferably silicone or medical-grade urethane, is used. Such materials have the required flexibility for comfort (close to gel-like) and elastic stiffness that allows the rim, which contours the skin surface, to flex appropriately under pressure and distribute the pressure evenly. (There are various overlapping Shore scales, but it is understood that any scale used will specify a material with important mechanical properties similar to the materials described above. Also note that these are novel materials that have not been widely used in medical applications until recently.) However, combinations of different materials and materials of different durometers are also considered. Since the rim material is sufficiently elastic (it is a very low durometer rubber), the skirt can spread out to a flat or nearly flat shape when pressure is applied and the downward force from the dome is counteracted by the skin. In alternative embodiments, the skirt may also be made of various durometers along its thickness and circumference, although this is more complex to manufacture, but it reduces bulkiness and makes the skirt more comfortable and concealable, provided that the concavity, taper angle, width, and flex characteristics under downward pressure maintain sufficient flex under physiological pressure, which is used to avoid pressure points and distribute pressure evenly. That is, softer durometer materials are more comfortable and conform to the skin but bulkier (thicker). (In some embodiments, softer durometer materials can be gel-like). The higher the durometer value, the thinner the wall but the less comfortable it is.Therefore, in some embodiments, the durometer value can vary, with the area near the center of the dome being harder to provide reinforcement to hold the dome together, and the periphery being softer to obtain comfort and conformity. In some embodiments, the concept of a variable durometer value can be utilized so that the durometer value gradually decreases towards the periphery. In such embodiments of a variable durometer value, it is necessary to achieve a delicate balance between comfort / conformity and reinforcement.

[0056] The design variables for the rim include the durometer value of the material (e.g., rubber), mechanical properties, thickness, taper ratio (angle), concavity, length, and shape. These variables are engineered / optimized to increase surface contact with increasing vacuum pressure in order to reduce the counterpressure acting on the skin. When the skirt flattens under downward pressure, the reaction force between the skirt and the tissue is uniformly distributed across and around the entire contact area. The above variables are engineered to have a preferably uniform distribution, so as to avoid concentration of pressure points and rather distribute across the entire skin contact area. The taper angle and concavity are also designed to uniformly distribute pressure under the widened skirt to avoid pressure points. As the pressure increases, the rim expands, bending outward, i.e., increasing its flex to increase the contact area and thereby reduce the counterpressure acting on the skin. This design results in a near-linear relationship between increasing vacuum pressure and increasing surface contact area. For example, when the vacuum pressure doubles, the rim flattens and expands, doubling the contact surface with the skin, and the pressure exerted by the rim on the skin remains low and uniform across the entire circumference. This property of the concave tapered flexible rubber sole, which increases surface contact with increasing downward force, balances the forces to keep skin pressure below harmful levels.

[0057] Figure 8 is a diagram similar to Figure 7A, schematically showing other depths of the dome shell 124 attached to the rim 122 of the expander 120, and also shows an alternative rim design having an additional inner thin-walled flexible rim 122 extending inward from the dome opening to increase the contact area with the skin in order to improve vacuum sealing. This inner thin-walled rim is very soft and flexible and is designed not to distribute pressure, but to improve surface contact with the skin, and therefore to improve sealing. The rim may include a feathered region 124 similar to the feathered region 112 in Figure 7A. The dome 124 may be permanently attached or replaceable, as described below.

[0058] Figures 7A to 7C show the increase in the contact area with increasing pressure. In Figure 7A, the vacuum expander 100 of the present invention is shown with the inner / lower surface 102a of the rim 102 not in contact with the tissue. In this non-contact position, the long, tapered low-durometer rubber rim and the nearly vertical axis of the rim skirt are shown. As shown, the concave configuration 114 is curved inward to embrace the chest contour, preventing the edge from springing up due to elastic contraction force as the periphery expands with increasing elastic elongation. The curved inward curvature embraces the tissue downward as the periphery expands. Under low pressure (arrow C in Figure 7B), as the rim 102 gradually opens, the rim 102 flexes (see area 118) to conform to the skin surface (mammary margin and curved chest contour). When a downward force increases under high pressure (arrow D in Figure 7C), the rubber rim 102 bends outward and expands to increase surface contact and maintain a safe level of pressure on the skin (Figure 7C), so the rubber rim 102 opens completely. The edges are wrapped around the periphery 109 to conform to the contours of the body.

[0059] As shown in Figures 7A to 7C and Figure 11, a thin, feathery inner rim (feathered lip) can be provided to increase the contact area and improve sealing. In some embodiments, as shown in the expander 140 of Figure 11, a fin pocket 142 or slit can be provided for inserting a fin 144 so as to follow the convex surface of the chest contour. The fin 144 can be reshaped and repositioned along the periphery of the rim to best follow the contour of the chest surface. The fin pocket 142 in some embodiments can address the problem that the skirt folds and collapses under the influence of peripheral tension, as shown in Figures 9C and 9D, and does not adequately wrap around the torso at the lateral chest boundary. By providing fins that are curved inward and have a feathery configuration, the inward force at the tip is reduced (see Figures 9A and 9B). The expander 140 may also have an inner feathered lip 143 to obtain further sealing. The concave shape 148 and feathered edge 150 of the rim 146 conform well to the torso, as described herein. As shown in the embodiments of Figures 7A to 7C, the non-stick tapered soft rubber sole 146 flexes outward under pressure. The dome 134 is attached to the rim 146 and has a periphery 136. Furthermore, in some embodiments, fins can be permanent components of the skirt. The dome shell may include a thickened rim or cane handle design at the periphery to increase surface contact with the soft skirt and prevent it from digging into the skirt.

[0060] With respect to shear stress (Problem 3), the vacuum expander of the present invention completely solves the problem of shear stress. The effects of force and shear can be understood by referring to Figure 1C and are also described in U.S. Patent No. 6,500,112 (same inventors as the present invention). (The entire disclosure of Patent No. 6,500,112 is incorporated herein by reference). Its purpose is to reduce skin shear stress by balancing the opposing pressure, as described in Patent No. 6,500,112. Figure 1C shows the inward deflection of the adhesive gel rim of a prior art Brava device for dissipating shear force, the left drawing shows the effect of shear, and the right drawing shows the reduction of shear stress due to the inwardly deflecting adhesive rim (sole).

[0061] In this invention, a soft rubber rim is provided instead of an adhesive rim. The soft rubber rim maintains the vacuum seal by faithfully supporting the contours of the body, thus eliminating the need for an adhesive layer (or other skin adhesive layer), and therefore the rim can be positioned non-fixed / non-adhesive / non-slip on the patient's skin to allow it to slide outward as a result. The device rim (skirt) may have a lubricant or other material that opens to wrap around the body and provides virtually frictionless sliding between the skin and the skirt. Since the rim is not bonded and fixed like in devices that use adhesive (or other adhesive material or structure) to fix the rim and the device in place, the skin can move freely, and tension can recruit surrounding skin as needed to dissipate harmful shear stress. With virtually free tissue replenishment, tensile, force, and shear stresses are reduced.

[0062] Accordingly, a vacuum expander of a particular embodiment of the present invention has a lubricated skin-to-rim sole contact area to allow frictionless skin replenishment (and sliding / gliding) that dissipates shear forces. The lubrication reduces the shear stress between the skin and the contact surface of the device. In the prior art, the skin is fixed to the contact surface via high-friction joints, or more frequently, via adhesives. The lubrication of the present invention eliminates this fixation, resulting in the elimination or reduction of shear forces.

[0063] The lubricant or low-friction film is applied by one or more of the following methods: a) by applying it to the skin before placing the device on the skin; b) by applying it to the bottom surface (sole) of the rim itself before placing it on the skin; and / or c) by incorporating the lubricant or low-friction film into the rim material to ensure constant lubrication. (The bottom surface (sole) refers to the surface closest to the breast tissue and is also referred to herein as the sole or base). The lubricant or low-friction film may be added separately, or the rim sole material may inherently have a low coefficient of friction, and as a result, the lubricant or film may not be necessary. Thus, the device is non-sticky / non-adherent to the skin and has a skin contact surface, either inherently or by adding a lubricant or film interface. Examples of such lubricants that can be used to eliminate or reduce the shear force between the skin and the contact surface (rim) of the device include grease, petroleum jelly, oil, wax, KY jelly, glycerin, hydroxyethylcellulose, water, liquid, jelly, cream, or any kind of wax, cocoa butter, petrolatum gel, petrolatum, Nivea, aloe vera, mineral oil, or other allergen-free lubricating materials with excellent skin resistance, or combinations thereof.

[0064] Figure 4 shows the harmful shear force (arrow A) generated when the vacuum inside the dome pulls the skin held beneath the rim inward. The rubber rim of the present invention is non-stick, allows free skin sliding, and has a low coefficient of friction with the skin (either inherent in the material or by applying a lubricant to the skin or rim sole). As shown by arrow B in Figure 4, the shear force is dissipated due to the sliding of the lubricating layer, which allows for inward replenishment of the skin.

[0065] The limited deflection of the prior art adhesive rim under higher pressure can be understood from the photographs in Figures 2A and 2B, where Figure 2A shows no vacuum and Figure 2B shows the application of a vacuum. Under higher pressure, the adhesive rim deflects inward, unable to dissipate further shear forces, reducing the expansion area of ​​the opening and compressing the breast like a vise. High pressure can also cause the silicone gel rim to delaminate and break. Figure 2C shows an example of how the limited inward deflection of the prior art adhesive rim can cause skin damage due to shear forces.

[0066] Figures 3A and 3B show examples of large and small domes (shells) of the prior art, which demonstrate that a larger opening that pulls a larger surface tends to generate an additional inward tensile force, and therefore an additional shear force concentrated on the rim, which can damage the skin. As shown, the rims 11a and 11b are attached to domes 10a and 10b, respectively, positioned on the skin S. When a suction force (vacuum) is applied to the small dome 10a (Figure 3A), the shell (dome) changes from a flat shape to a domed shape, and 3 cm of skin (breast width) is stretched by 10% (3 mm). When a suction force (vacuum) is applied to the large dome 11b (Figure 3B), the shell (dome) changes from a flat shape to a domed shape, and 12 cm of skin (breast width) is stretched by 10% (1.2 cm). If the rim is firmly held at the edge (i.e., by prior art adhesive), a large rupture of 1.2 cm that cannot be adapted to will result in skin tearing. The device of the present invention prevents this by 1) allowing the rim to flex inward, 2) having a lubricated joint that freely replenishes the surrounding skin, and 3) having frictionless replenishment at the non-adherent rim base.

[0067] In a preferred embodiment, the vacuum expander of the present invention has a portable vacuum pump having a pressure control mechanism. However, in an alternative embodiment, a spherical manual pump can be used. The manual pump may include a pressure relief valve to prevent the vacuum pressure from reaching harmful levels.

[0068] Since the device of the present invention does not require surface tension, it can, alternatively, function without a pump. In such embodiments, the vacuum source is the elastic contraction force of the rubber sole. The device is placed over the breast, and air is "released" until the rim is completely flat. At that point, the vacuum pressure inside the dome is a function of the elastic contraction force of the rubber and the surface opening area of ​​the dome (pressure = force / surface area). Assuming a constant surface area of ​​the breast, the shape design and elastic modulus of the rubber sole determine the force required to maintain the pressure within a safe therapeutic range. A relief valve may also be included for further safety. In other words, the device does not require an active vacuum because it utilizes the surface tension of the dome section to adhere to the skin. This concept relies on releasing air from the flexible dome and the natural contraction force of the dome and / or dome rim to pull the breast tissue.

[0069] In some embodiments, a dedicated garment bra can hold the device in place. This can have the same effect as pressing and folding the feathery edge of the skirt to wrap around the breast contour in order to maintain a seal. The bra has first and second openings or openings that hold the rubber rim and dome. This component securely fastens the device, as a non-adhesive device would otherwise fall off as soon as the pressure decreases. The bra may have a special design that includes a series of reinforcing straps and / or padding cushions, which keep the loose feathery edge of the skirt firmly in contact with the skin around the entire circumference of the breast to ensure a vacuum seal. The bra hugs the body contour so that the feathery edge remains in contact with the skin. Reinforcing bands can connect the bra to the rim.

[0070] In some embodiments, an additional tapered, thin-walled inner rim can be provided that harmonizes with the outer rim to increase the sealing surface area without hindering the vacuum expansion force.

[0071] In some embodiments, the rim is radially reinforced with a series of adjustable, thin-walled, tapered, concave fins to better conform to the body contour. Figures 9C and 9D are photographs showing how the thin-walled, feathery edge of the rim curls up around the periphery in certain applications, preventing the edge from wrapping to follow the chest contour, while Figures 9A and 9B are photographs showing how the rim of the vacuum expander of the present invention is molded to wrap around the chest and conform to the contour of the skin surface to avoid the pitfalls of the expander in Figures 9C and 9D. In these alternative embodiments of Figures 9A and 9B, the rubber rim has thin-walled, tapered, fin-shaped, inwardly curved ribs to wrap around the chest and conform to the contour of the skin surface. The ribs can be inserted into pre-formed pockets on the outer surface of the skirt to provide further inward curvature, if necessary. The ribs can be positioned at selected locations where they are needed to best support the patient's specific chest wall surface shape. Furthermore, the rim may have arched notches between the fins to prevent inversion as the periphery stretches with increasing surface contact. An embodiment shown in Figure 12 illustrates an expander with tapered fins, where fin 153 extends from the periphery 156 of the dome 154 to the end 155 of the edge 157 of the skirt 152. Figure 11 also shows a fin 134 reinforcing a rim 146 that extends to the periphery 136 of the dome shell.

[0072] Furthermore, Figure 6F shows the left-right asymmetry of the rim as in the embodiments described above, with a longer lateral length to conform to the lateral chest, a shorter medial length on the sternum to limit medial overlap, and a deeper lateral angle to embrace the sides of the chest. The arrangement, curvature, and length of the ribs / fins can be adjusted to suit individual patients; that is, ribs / fins of different sizes, curvatures, and stiffnesses can be provided along the circumference of the rim where needed to achieve the best airtight fit based on the patient's torso contour. The photograph in Figure 6F shows various diagrams of embodiments of the asymmetric dome of the present invention. Note the asymmetry of length and curvature between the inner and lateral sides of the dome skirt. Also note the length, the near-vertical design, and the gradually inwardly curved feather-like edges.

[0073] In some embodiments, the rim may have a curved periphery (like a duck's foot) that is pointed at the reinforcing rim and concave in between.

[0074] In some embodiments, ribs of varying curvatures and lengths, appropriately inserted inside the rubber skirt at various points within the periphery, can help the rubber skirt adapt better to potentially complex and variable surface contours. Furthermore, the rim edge may have an arched periphery with its apex located at the site of the reinforcing rib. Additionally, variable durometer structures, as described herein, can achieve the same effect without additional bulk.

[0075] In some embodiments, interchangeable breast-shaped dome shells can be provided. Connector mechanisms, such as a circumferential fastening / retaining mechanism 132, can be provided to fix the rubber sole (rim) 132 to the interchangeable shell (Figure 10) to allow for easy removal and replacement of the selected dome. It should also be noted that the design and circumference of the rubber skirt are slightly smaller than the circumference of the rigider shell dome in the bonding area, and the stretching and contracting of the rubber skirt itself is configured to already provide an inherent lock and seal, similar to a food Tupperware seal. That is, for example, a thick rubber band or elastic string can be used to provide domes of various depths with a simple snap-fastening or spring-lock fastening joint between the silicone rim skirt and the dome. When in use, if the connector mechanism is released, one dome is removed and a larger dome is secured to the rim by the connector mechanism. This allows the wearer to wear the smallest and most harmless (most concealing) dome, still providing 1-2 cm of leeway for expansion. As the breast expands to fill the small dome, the user can easily switch to a slightly larger dome while keeping the device as concealed as possible, which is beneficial as the device needs to be worn almost continuously.

[0076] Furthermore, it is intended that markers that need to be matched be placed on the dome and / or skirt, so that when the dome is removed and replaced, the patient can easily match the top and bottom, left and right, to properly join the new dome, for example, to maintain the desired asymmetrical configuration. This can ensure that the dome is replaced in the correct orientation (especially if the same type is used for the left and right domes and skirt).

[0077] Figure 13 shows, for example, multiple depths of dome shells from AA bra cups to DDD bra cups. Domes of different depths are attached to a constant base so as to interconnect with the rim skirt. Examples of domes of various sizes, e.g., 164a, 164b, 164c, and 164d, are all shown attached to the base in Figure 13 for illustrative purposes only, so please understand that only one dome is attached to the base / rim at a time (the size gradually increases as the breast expands over time). More or fewer domes may be provided. The device can be sold as a kit with multiple sizes of depth domes that are detached from the rim for selective attachment by the clinician or patient as needed to best fit the breast as it expands. Alternatively, the device can be sold as a kit with multiple sizes / depth domes all permanently bonded to a rubber rim. Gradually increasing sizes of domes allow the wearer to use the smallest, most concealing dome and move to the next larger size as the breast fills that dome.

[0078] For the device of the present invention to be effective, it needs to be worn almost all the time. Therefore, it is preferable that it can be concealed like a padded bra and that it is as easy to wear as a regular padded bra. Preferably, the increase in the original breast protrusion should not exceed 1-2 cm. Therefore, it is advantageous that the dome be as small as possible, still leaving room for vacuum expansion. Once the wearer fills the dome, the wearer can select the next dome / rim or proceed to the next increment by attaching the dome to the same base (rim) in a dome embodiment that can be removed and replaced with a larger dome. (Figure 13 shows different sized domes to illustrate a comparison of different sized domes coupled to a rim).

[0079] Figures 14A to 14D show embodiments of the expander of the present invention incorporated into a bra; Figures 14A and 14B show a mastectomy patient wearing the bra and holding the miniature pump of the present invention that applies vacuum for expansion; and Figures 14C and 14D show a cosmetic breast augmentation patient wearing the bra of the present invention used with the miniature pump of Figure 14A. As illustrated, each opening in the bra receives a dome and / or rim for placement on the skin. The dome and / or rim can be attached to the bra so that the internal volume of the dome communicates with the opening. A tube connects the vacuum to the inside of the dome through the opening of the dome. The bra may include the reinforcing materials described above.

[0080] The dome is one shell shape that can be used, and other shell shapes may also be utilized. Note that the various shell and rim materials and structural / features disclosed herein are used for braja shells, including interchangeable shell versions.

[0081] In a preferred embodiment, the dome is made of clear plastic and is translucent enough to visualize the expanded space between the nipple and the top of the dome. The dome section can be permanently attached to the skirt by adhesive, ultrasonic welding, or cured together with the skirt in a complex mold using potentially different rubbers. In an alternative embodiment, the dome section of the device may be a separate plastic or rubber component that can be attached to and detached from the rim skirt.

[0082] Although the rigid shell is described in this specification as a molded dome, it is not limited to this shape, and since the pressure is isotropic, it can be other shapes such as a cube or cylinder to form a vacuum chamber. Accordingly, the description of the shell as used herein in relation to the term "dome" can be fully applied to non-domed shells.

[0083] Please understand the separation / distinction between the dome (shell) and the rim / skirt. If the skirt / rim is made of rubber, the durometer may gradually change from the skirt to the dome. Alternatively or additionally, the dome can be rigidified with reinforcing ribs. There may be a skin, sheet, etc. that covers both the dome and the skirt. The skin, sheet, etc. can be made of a hard protective durometer material or a soft durometer material.

[0084] Please understand that materials other than rubber can be used for the rim (and other components / features), and that this falls within the scope of the present invention.

[0085] The present invention can be used in combination with the concept of surface tension in U.S. Patent No. 10,433,947 when a rubber dome is used. In this combined embodiment, the wearer would need to find an appropriate dome size that completely encloses the breast. With no vacuum space and the skin in full contact with the inner surface of the dome, the surface tension between the dome and the skin would maintain frictionless adhesion. Air is released from the flexible dome and will pull on the breast, relying on the natural contraction force of the dome and / or dome rim. The expansion force will be a function of the elastic contraction force properties of the rim / flexible dome structure.

[0086] Furthermore, the present invention provides a method for using a dilator. For example, one method provides shear stress reduction, which includes positioning a device having a shell and a rim extending from the shell configured to contact the patient's body, the rim being positioned non-adherent on the body and stretching laterally outward relative to the shell when an tensile force is applied within the shell, so that the shear stress is reduced at the junction between the skin inside the shell and the skin pressed down by the rim. This method may include the step of providing an tensile force by the elastic contraction force of one or both of the shell and / or the rim, or by applying a vacuum within the shell.

[0087] Those skilled in the art will understand that elements and features shown or described in relation to one embodiment can be combined with those of another embodiment without departing from the scope of this disclosure, and will understand further features and advantages of the subject matter now disclosed based on the description provided.

[0088] While the present invention is described with reference to specific embodiments constituting non-limiting examples, those skilled in the art will understand that various changes and modifications can be made and equivalents can be substituted without departing from the spirit and scope of the invention as defined in the appended claims. In addition, many modifications can be made to introduce specific situations, materials, compositions of substances, processes, process steps or sets of steps into the objective spirit and scope of the invention. All such modifications are intended to be within the scope of the appended claims.

[0089] If a range of values ​​is provided, please understand that values ​​between each of the specified ranges are included within the scope of this invention.

[0090] Throughout this disclosure, terms such as “approximately,” “about,” “generally,” and “substantially” should be understood to allow for variation in any numerical range or concept to which they relate. For example, the use of terms such as “nearly,” “about,” and “generally” should be understood to include variation of the order of 25%, or to allow for deviations in manufacturing tolerances and / or design.

[0091] Terms such as “First,” “Second,” and “Third” can be used to describe various operations, elements, components, areas, and / or sections, but these operations, elements, components, areas, and / or sections should not be limited by the use of these terms in that they are used to distinguish one operation, element, component, area, or section from another operation, element, component, area, or section. Accordingly, unless expressly stated otherwise, the first operation, element, component, area, or section may be referred to as the second operation, element, component, area, or section without departing from the scope of this specification.

[0092] All claims are incorporated herein as further disclosures and represent embodiments of the present disclosure. The phrases “at least one of A, B, and C” and “A and / or B and / or C” should be interpreted as including A alone, B alone, C alone, or any combination of A, B, and C, respectively. Other embodiments of the present invention are described below. [Embodiment 1] A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an extrinsing force that expands tissue; and a rim coupled to the shell and adapted to contact the patient's skin, A tissue expander wherein the rim is non-fixed to the patient's skin and moves laterally outward relative to the shell under the application of vacuum as the rim gradually stretches under increasing pressure. [Embodiment 2] The tissue expander according to Embodiment 1, wherein the shell is dome-shaped. [Embodiment 3] The tissue expander according to Embodiment 1, wherein the rim is made of synthetic rubber and has a lubricating layer on its bottom surface for sliding on the skin, thereby reducing shear stress between the rim and the contact surface with the skin. [Embodiment 4] The tissue expander according to Embodiment 1, wherein the rim has a lubricant that allows the rim to slide in order to provide reduced frictional contact with the skin and to reduce shear stress between the rim and the contact surface of the skin. [Embodiment 5] The tissue expander according to Embodiment 1, wherein the rim has a non-adherent tissue contact lower surface. [Embodiment 6] The tissue expander according to Embodiment 5, wherein the non-adhesive tissue contact lower surface is a non-stick lower surface. [Embodiment 7] The tissue expander according to Embodiment 1, wherein the rim has a concave tapered portion that bends and opens to form a skirt that spreads laterally. [Embodiment 8] A tissue expander according to Embodiment 1, wherein when downward pressure is applied by the vacuum, the rim conforms to the contours of the patient's body. [Embodiment 9] The tissue expander according to Embodiment 1, wherein when a downward force is applied, the rim flexes to increase the contact surface with the skin and prevents an increase in counterpressive pressure on the skin. [Embodiment 10] The tissue expander according to Embodiment 1, wherein the rim has downward-facing feather-shaped edges to enclose a part of the patient's body and interlock with the patient's torso. [ment11] The tissue expander according to Embodiment 1, wherein the rim has a flexible edge that is thicker than the inner portion of the rim, and the edge is more flexible than the inner portion. [Embodiment 12] The tissue expander according to Embodiment 1, wherein the rim is tapered, curved inward, concave, and has an axis less than 20 degrees from the vertical. [Embodiment 13] The tissue expander according to Embodiment 1, wherein the rim is asymmetrical. [Embodiment 14] The tissue expander according to Embodiment 13, wherein the rim has a narrower inner skirt and a more curved lateral inward-facing skirt that provides a deeper concave surface and a longer length than the inner side to wrap around the contours of the body. [Embodiment 15] The tissue expander according to Embodiment 1, wherein the rim forms a skirt, and when downward pressure is applied, the downward force from the shell is counteracted by the skin, and the rim remains concave at its lateral periphery, and can expand from concave to convex or substantially flat at the point of maximum pressure, and the reaction force between the skirt and the tissue is uniformly distributed over the skin contact area to avoid pressure points associated with increasing pressure. [Embodiment 16] The tissue expander according to Embodiment 1, wherein there is a substantially linear relationship between the increase in vacuum pressure and the increase in the surface contact area of ​​the rim. [Embodiment 17] The tissue expander according to Embodiment 1, wherein the rim further comprises a fin pocket. [Embodiment 18] The tissue expander according to Embodiment 1, wherein the rim has a coupling mechanism for the release attachment of the shell, allowing a first-size shell to be removed from the rim and a second-size shell to be attached to the rim. [Embodiment 19] The tissue expander according to Embodiment 1, wherein the shell is detachably bondable to the rim, and shells of various sizes can be selectively bonded to the rim. [Embodiment 20] The tissue expander according to Embodiment 1, further comprising second and third shells attachable to the rim, wherein the second and third shells are progressively deeper in size. [Embodiment 21] A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an extrinsing force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim has a concave lower surface, and at least a portion of the concave lower surface deforms when a vacuum is applied and inverts to a convex surface when a vacuum is applied, the tissue expander. [Embodiment 22] The tissue expander according to embodiment 21, wherein when a vacuum is applied, a portion of the rim changes from a concave surface to a convex surface. [Embodiment 23] The tissue expander according to embodiment 22, wherein the lateral periphery of the lateral rim remains concave to maintain sealing. [Embodiment 24] The tissue expander according to embodiment 21, wherein the rim changes angle from more vertical to more horizontal when pressure is applied. [Embodiment 25] The tissue expander according to embodiment 21, wherein the rim can flex to a greater extent than the thicker, inner portion of the rim and has a tapered surface that gradually decreases in thickness toward the periphery to provide a thinner, more flexible edge. [Embodiment 26] The tissue expander according to embodiment 21, wherein the rim is tapered to the thickness of a feather that forms a feather-shaped edge. [Embodiment 27] The tissue expander according to embodiment 21, wherein the rim is asymmetrical. [Embodiment 28] The tissue expander according to embodiment 27, wherein the lateral side of the rim has a longer and deeper concave surface than the inner side of the rim. [Embodiment 29] The lower surface of the rim conforms to the contour of the patient's body, as described in Embodiment 21 of the tissue expander. [Embodiment 30] The tissue expander according to embodiment 21, wherein the rim flexes in response to increasing force, increasing surface contact with the skin and preventing an increase in counterpression pressure on the skin. [Embodiment 31] The tissue expander according to embodiment 21, wherein the rim has an inward curve that slopes downward from the horizontal plane to enhance the bite of the patient's body. [Embodiment 32] The tissue expander according to embodiment 21, wherein the rim is made of a low-durometer material. [Embodiment 33] The tissue expander according to embodiment 21, wherein when downward pressure is applied, the reaction force between the rim and the skin is uniformly distributed over the skin contact area. [Embodiment 34] The tissue expander according to embodiment 21, wherein as the vacuum pressure increases, the rim expands and its deflection increases, increasing the contact area with the skin and reducing the counterpressure on the skin. [Embodiment 35] A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an extrinsing force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is a tissue expander having a feather-shaped edge that increases the contact area with the skin. [Embodiment 36] The tissue expander according to embodiment 35, wherein the rim has a non-adhesive tissue contact lower surface. [Embodiment 37] The tissue expander according to embodiment 35, wherein the rim is asymmetrical. [Embodiment 38] The tissue expander according to embodiment 37, wherein the rim has a narrower inner skirt and a more curved lateral inward-facing skirt that provides a deeper concave surface and a longer length than the inner side to wrap around the contours of the body. [Embodiment 39] a) A first opening and b) A second opening and c) A first shell having a first rim extending laterally outward, wherein the first opening is dimensioned and configured to receive one or both of the first shell and the first rim, and the first rim is non-fixedly positionable in contact with the wearer's skin, d) A second shell having a second rim extending laterally outward, wherein the second opening is dimensioned and configured to receive one or both of the second shell and the second rim, and the second rim is non-fixedly positionable in contact with the wearer's skin, Equipped with, e) A bra in which the first and second rims are slidable outward while maintaining contact with the skin. [Embodiment 40] The rim has a concave lower surface, as described in embodiment 39. [Embodiment 41] The bra according to embodiment 39, further comprising reinforcing bands connecting the bra to the first and second rims. [Embodiment 42] The bra according to embodiment 39, further comprising bra straps, wherein when an tensile force is applied to the wearer's skin within the first and second shells, the bra straps allow the first and second rims to slide laterally outward while maintaining skin contact. [Embodiment 43] The bra according to embodiment 42, wherein the stretching force is applied by an external vacuum communicating with the first and second shells. [Embodiment 44] The bra according to embodiment 42, wherein the stretching force is applied by the elastic contraction forces of the first and second shells. [Embodiment 45] The bra according to embodiment 39, further comprising reinforcing straps that maintain the feathery edges of the first and second rims in firm contact with the skin around the breast in order to ensure a vacuum seal. [Embodiment 46] The bra according to embodiment 39, wherein the first and second rims are made of low-durometer synthetic rubber. [Embodiment 47] The bra according to embodiment 39, wherein the first and second rims have downward-facing feather-shaped edges that increase the area in contact with the skin. [Embodiment 48] a) A first opening and b) A second opening and c) A first shell having a first rim extending laterally outward, wherein the first opening is dimensioned and configured to receive one or both of the first shell and the first rim, and the first rim is non-fixedly positionable in contact with the wearer's skin, d) A second shell having a second rim extending laterally outward, wherein the second opening is dimensioned and configured to receive one or both of the second shell and the second rim, and the second rim is non-fixedly positionable in contact with the wearer's skin, Equipped with, e) Each of the first and second rims of the bra gradually stretches laterally under increasing pressure. [Embodiment 49] The bra according to embodiment 48, wherein the first and second rims are made of a low-durometer synthetic rubber material. [Embodiment 50] The bra according to embodiment 48, wherein the first and second rims have an inward curve that slopes downward from the horizontal plane to enhance the fit with the wearer's body. [Embodiment 51] The bra according to embodiment 48, wherein the stretching force is applied by an external vacuum communicating with the dome. [Embodiment 52] The bra according to embodiment 48, wherein the rim has a downward-facing feather-shaped periphery that increases the area in contact with the skin. [Embodiment 53] a) A first opening and b) A second opening and c) A first shell having a first rim extending laterally outward, wherein a first opening is dimensioned and configured to receive one or both of the first shell and the first rim, and the first rim is non-fixedly positionable in contact with the wearer's skin, d) A second shell having a second rim extending laterally outward, wherein the second opening is dimensioned and configured to receive one or both of the second shell and the second rim, and the second rim is non-fixedly positionable in contact with the wearer's skin, Equipped with, e) A bra in which each of the first and second rims has a concave underside that deforms and inverts into a convex surface when a vacuum is applied. [Embodiment 54] The bra according to embodiment 53, wherein the rim changes angle from more vertical to more horizontal when pressure is applied. [Embodiment 55] The bra according to embodiment 53, further comprising reinforcing bands for holding the bra to the first and second rims. [Embodiment 56] The bra according to embodiment 53, wherein the first and second rims have downward-facing feather-shaped edges that increase the area in contact with the skin. [Embodiment 57] The bra according to embodiment 53, further comprising a reinforcing strap for maintaining the feathery periphery of the rim in firm contact with the skin.

Claims

1. A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an extrinsing force that expands tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is non-fixed to the patient's skin, and as the rim stretches under increasing pressure, it moves laterally outward relative to the shell under the application of vacuum. The rim has a concave lower surface, and at least a portion of the concave lower surface deforms when a vacuum is applied and inverts to a convex surface when a vacuum is applied, the tissue expander.

2. The tissue expander according to claim 1, wherein the rim is made of synthetic rubber and has a lubricating layer or lubricant on its bottom surface for sliding on the skin, thereby reducing the shear stress between the rim and the contact surface with the skin.

3. The tissue expander according to claim 1, wherein the rim has a non-adhesive, non-stick tissue-contacting lower surface.

4. A tissue expander according to any one of claims 1 to 3, wherein when a downward pressure is applied by the vacuum, the rim conforms to the contour of the patient's body, the rim flexes to increase the contact surface with the skin, and prevents an increase in counterpressure against the skin.

5. The tissue expander according to claim 1, wherein the rim has downward-facing feather-shaped edges to enclose a part of the patient's body and interlock with the patient's torso.

6. A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an stretching force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is non-fixed to the patient's skin, and as the rim stretches under increasing pressure, it moves laterally outward relative to the shell under the application of vacuum. A tissue expander wherein the rim has a flexible edge that is thinner than the inner portion of the rim, and the edge is more flexible than the inner portion.

7. The tissue expander according to claim 6, wherein the rim has a concave tapered portion that bends and opens to form a skirt that spreads laterally.

8. A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an stretching force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is non-fixed to the patient's skin, and as the rim stretches under increasing pressure, it moves laterally outward relative to the shell under the application of vacuum. A tissue expander having a rim that is tapered, curved inward, concave, and whose axis is less than 20 degrees from the vertical.

9. The tissue expander according to claim 1, wherein the rim is asymmetrical and has a narrower inner skirt and a more curved, laterally inward-facing skirt that provides a deeper concave surface on the later side and a longer length than the inner side to wrap around the contours of the body.

10. The tissue expander according to claim 1, wherein the rim forms a skirt, and when downward pressure is applied, the downward force from the shell is counteracted by the skin, and the rim remains concave at its lateral periphery, and can expand from concave to convex or substantially flat at the point of maximum pressure, and the reaction force between the skirt and the tissue is uniformly distributed over the skin contact area to avoid pressure points associated with increasing pressure.

11. The tissue expander according to claim 1, wherein the rim further comprises a fin pocket.

12. A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an stretching force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is non-fixed to the patient's skin, and as the rim stretches under increasing pressure, it moves laterally outward relative to the shell under the application of vacuum. A tissue expander, wherein the rim has a coupling mechanism for the release attachment of the shell, allowing a first-size shell to be removed from the rim and a second-size shell to be attached to the rim.

13. The tissue expander according to claim 1, wherein the rim changes angle from more vertical to more horizontal when pressure is applied.

14. The tissue expander according to claim 1, wherein the rim has an inward curve that slopes downward from the horizontal plane in order to enhance the bite of the patient's body.

15. A tissue expander comprising: a shell; an opening in the shell communicating with an external vacuum source to apply a vacuum into the shell to impart an extrinsing force to expand tissue; and a rim coupled to the shell and adapted to contact the patient's skin, The rim is non-fixed to the patient's skin, and as the rim stretches under increasing pressure, it moves laterally outward relative to the shell under the application of vacuum. A tissue expander in which, as the vacuum pressure increases, the rim expands and its deflection increases, thereby increasing the contact area with the skin.

16. The tissue expander according to claim 15, wherein the rim has a concave lower surface, and at least a portion of the concave lower surface deforms when a vacuum is applied and inverts to a convex surface when a vacuum is applied.

17. A tissue expander in the form of a bra, a) The first opening and b) A second opening and c) A first shell having a first rim extending laterally outward, wherein the first opening is sized and configured to receive one or both of the first shell and the first rim, and the first rim is non-fixedly positionable in contact with the wearer's skin, d) A second shell having a second rim extending laterally outward, wherein the second opening is sized and configured to receive one or both of the second shell and the second rim, and the second rim is non-fixedly positionable in contact with the wearer's skin, Equipped with, e) The tissue expander according to any one of claims 1 to 3, 5, 6, 8 to 16, wherein the second rim is slidable outward while maintaining contact with the skin.

18. The tissue expander according to claim 17, further comprising a bra strap, wherein when an tensile force is applied to the wearer's skin within the shell, the bra strap allows the rim to slide laterally outward while maintaining skin contact.

19. The tissue expander according to claim 17, further comprising a reinforcing strap that maintains the feathery periphery of the rim in firm contact with the skin around the breast in order to ensure a vacuum seal.

20. a) The first opening and b) A second opening and c) A dome-shaped first shell having a first rim extending laterally outward, wherein the first opening is sized and configured to receive one or both of the first shell and the first rim, and the first rim is non-fixedly positionable in contact with the wearer's skin, d) A second shell having a second rim extending laterally outward, wherein the second opening is sized and configured to receive one or both of the second shell and the second rim, and the second rim is dome-shaped and non-fixedly positionable in contact with the wearer's skin, Equipped with, e) Each of the first and second rims of the bra gradually stretches laterally under increasing pressure.

21. The bra according to claim 20, wherein the first and second rims have an inward curve that slopes downward from the horizontal plane to enhance the fit with the wearer's body.

22. The bra according to claim 20, wherein the stretching force is applied by an external vacuum communicating with the dome.

23. The bra according to claim 20, wherein the tensile force is applied by the elastic contraction forces of the first and second shells.

Images