WO2007084285A2

WO2007084285A2 - Implantable nipple prosthetic device

Info

Publication number: WO2007084285A2
Application number: PCT/US2007/000546
Authority: WO
Inventors: Anthony L. Clark; Brian W. Powell
Original assignee: Asteame Medical Devices, Inc.
Priority date: 2006-01-12
Filing date: 2007-01-10
Publication date: 2007-07-26
Also published as: WO2007084285A3

Abstract

A surgically implantable prosthetic nipple and breast, each having comfort and aesthetic enhancing elastic-return properties that respectively approximate a human nipple and breast, are formed using a material that is inert to the human body, including for example a negative thermal expansion material such as Zirconium tungstate (ZrW2O8). The nipple and breast may be single or multi-chambered and /or have a plurality of ribs or other spring-like structure to respectively approximate the shape, size, and dynamic characteristics of a human nipple and breast.

Description

IMPLANTABLE NIPPLE PROSTHETIC DEVICE COPYRIGHT NOTICE

[0001] A portion of the disclosure of this patent document contains material which is subject to copyright or mask work protection. The copyright or mask work owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright or mask work rights whatsoever.

RELATED APPLICATIONS

[0002] This application is related to and claims priority from United States

Provisional Patent Application No. 60/758,144, titled "Implantable Nipple Prosthetic device," filed on January 12, 2006, the entire contents of which are hereby incorporated herein by reference.

FIELD OF THE DISCLOSURE

[0003] This invention relates to nipple prosthetic devices, and, more particularly, to nipple prosthetic devices that may be surgically implanted in a breast mound.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The following description, given with respect to the attached drawings, may be better understood with reference to the non-limiting examples of the drawings, wherein:

[0005] Figs. l(a)-l(c) show external views of implantable prosthetic nipple devices;

[0006] Figs. 2(a)-2(b) illustrate a cross section views of single chamber implantable nipple prosthetic devices; [0007] Fig. 3(a) illustrates a cross section, internal view of a multiple chamber implantable nipple prosthetic device in a relaxed state;

[0008] Fig. 3(b) shows a cross section view of multiple chamber implantable nipple prosthetic device of Fig. 3(a) in a compressed state;

[0009] Fig. 4(a) illustrates a cross section view of a single chamber implantable nipple prosthetic device in a relaxed state;

[0010] Fig. 4(b) shows a cross section view of the single chamber implantable nipple prosthetic device of Fig. 4(a) in a compressed state;

[0011] Fig. 5(a) shows an external isometric view of an implantable reconstructive nipple device;

[0012] Fig. 5(b) shows an external side elevation view of the implantable prosthetic nipple device of Fig. 5(a); and

[0013] Fig. 5(c) shows a plan view of the implantable prosthetic nipple device of Fig. 5(a);

[0014] Fig. 5(d) shows a front elevation external view the implantable reconstructive nipple device of Fig. 5(a);

[0015] Figs. 6(a)-6(d) show various views of an implantable prosthetic nipple device similar to that shown in Figs. 5(a)-5(d); and

[0016] Figs. 7(a)-7(b) show an exemplary embodiment of a ribbed breast implant.

THE PRESENTLY PREFERRED EXEMPLARY EMBODIMENTS INTRODUCTION & BACKGROUND

[0017] Nipple reconstructive (or constructive) surgery can be performed on patients as a result of cancer treatment, trauma, congenital abnormalities (such as an inverted nipple) or for cosmetic or other reasons. For example, following a mastectomy procedure to treat breast cancer, nipple reconstruction surgery is most often done as the final stage of the breast reconstruction process. [0018] Nipple reconstruction greatly increases the achievement of a realistic looking breast and provides tangible psychological benefits to patients who have undergone breast reconstruction. Nipple reconstruction, as part of breast reconstruction, has generally replaced the use of external prosthetic nipple devices for patients who have undergone mastectomies.

[0019] Contemporarily, nipples are generally reconstructed from incised local flaps of skin and fat that are elevated from the breast mound to create a protrusion. The incised donor sites are typically closed by suturing the opposing skin edges together. A less commonly used procedure covers the donor site with a skin graft. Regardless of the specific technique, nipple size, projection, position, shape, and color are key considerations in the reconstruction process. [0020] Despite a surgeon's technique and expertise with a particular skin flap procedure, the created nipple will experience shrinkage and may even completely flatten. External compression forces on the nipple, such as from wearing a bra, and tensile forces from scar tissue that forms within the donor site may cause the created nipple to flatten. It is not uncommon for the ultimate result to be a very small protrusion or no protrusion at all.

[0021] U.S. Provisional Application Serial Number 60/628,158 and U.S.

Patent Application Serial Number 11/254,760 teach using an apparatus that postoperatively protects against tensile, shearing and compressive forces on a reconstructed nipple. The result being a more optimal nipple projection. [0022] Other prior art related to breast reconstruction focuses on experimental and non-commercial breast prostheses or implants. U.S. Patent Number 3,986,213 is a representative example of patent art dealing with surgically implantable breast prostheses. In contrast, very little of the breast reconstruction prior art addresses implantable nipple prostheses, U.S. Patent Number 4,778,465 to Wilkins being a representative exception. The '465 Wilkins patent describes a surgically implantable areola and nipple prosthesis with a base integrally formed with a nipple forming protrusion (see, e.g., Wilkins' figures 2-5 and related description).

[0023] A major deficiency of the prior art implantable nipple prostheses is that they are extremely hard to the touch; lacking the pliability, compliance and tactile realism of a natural nipple.

DESCRIPTION

[0024] Fig. 1 (a) shows an implantable nipple prosthetic device 100a having a specifically sized, sealed and sterilized outer chamber HOa. Figs. l(b)- l(c) show similar devices 100b, 100c with outer chambers HOb and 110c, respectively. The outer chambers 110a, HOb, HOc are preferably of an inert synthetic construction, and may be comprised of, but not limited, to silicone, plastic, polymer, or a composite / combination composition. Preferably a thin-film (not shown) external to the outer chamber(s) provides containment for the internal components of an implantable nipple prosthetic device. The thin-film may comprise silicone or some other suitable material.

[0025] According to some exemplary embodiments, an implantable nipple prosthetic device can be characterized as being an exposed chamber, single chamber, or multiple chamber design. Those skilled in the art will realize and understand, upon reading this description that these categorizations are for the purposes of this description, and are not intended to limit the scope of the invention.

[0026] Figs. l(a)-l(b) illustrate closed chamber devices, while Fig. l(c) illustrates an exposed-chamber device, which is characteristic of an implantable nipple prosthetic device that has no end-caps or only one end-cap (i.e., that is open on at least one end). The exposed-chamber device 100c of Fig. l(c) has a chamber 120c that is open on at least one end of the device such that the interior is exposed. [0027] Figs. 2 (a)-2(b) and 3(a)-3(b) are cross-sectional views of exemplary single-chamber implantable nipple prosthetic devices. The device 200a of Fig. 2(a) has an outer chamber 210a and an internal containment section 212a. Similarly, the device 200b of Fig. 2(b) has outer chamber 210b and internal containment section 212b. The internal containment sections 212a, 212b may contain an inert gas such as nitrogen or the like. As with the devices in Figs. l(a)- l(c), preferably a thin-film (not shown) external to the outer chambers provides containment for the internal components of an implantable nipple prosthetic device.

[0028] Figs. 3(a)-3(b) illustrate cross sectional views of a single chamber implantable nipple prosthetic device 300, showing relaxed and compressed views of the device, respectively. The internal containment section 302 forms a single chamber that allows for the internal displacement of a filler gas 304 and a fluid 306 that are contained therein.

[0029] The fluid 306, preferably viscous, may be a saline solution, a silicone solution or any engineered fluid, and is used as filler for some amount less ^' than 100% of the remainder of the chamber's volume. The fluid's viscosity and density preferably have a tuned response damping capacity to impart a level of compliance as well as resistance to an external force imparted to the device. [0030] The filler gas 304 and the fluid 306 are preferably inert. The inert filler gas 304 may be, e.g., nitrogen, and preferably substantially fills the remainder of the chamber's volume not filled by the fluid. The filler gas 304 may be displaced by the viscous fluid 306 as a result of application of an external force to the device.

[0031] Figs. 4(a)-4(b) illustrate cross sectional views of a multi-chamber implantable nipple prosthetic device 400, showing relaxed and compressed views of the device, respectively. The internal containment section 402 forms multiple- chambers (two chambers, first chamber 402-1, and second chamber 402-2 in the embodiment shown) connected via at least one opening 408. The structure allows for the internal displacement of a filler gas 406 (in first chamber 402-1) and a fluid 406 (in second chamber 402-2) that are contained respectively therein. As with the single-chamber devices described above, preferably the filler gas 404 and the fluid 406 are inert.

[0032] The filler gas 404 may be, e.g., nitrogen, and preferably substantially fills the first chamber's volume. The filler gas 404 may be displaced by the viscous fluid 406 as a result of application of an external force to the device. [0033] The fluid 406, preferably viscous, may be a saline solution, a silicone solution or any appropriately engineered fluid, and is used as filler for substantially all of the second chamber's volume. The fluid's viscosity and density preferably have a tuned response damping capacity to impart a level of compliance as well as resistance to an external force imparted to the device. [0034] An implantable nipple prosthetic device is a purpose built-construct that forms a compliant backing, which has a memory-profile that maintains the shape and projection the reconstructed nipple. In order to retain the memory- profile, the device may include a spring mechanism, preferably a composite spring of a specified constant which shall accommodate a tuned response and position memory. Figs. 3(a)-3(b), 4(a)-4(b) illustrate an internal profile of a retention spring 310, 410, respectively, for an example implantable nipple prosthetic device. [0035] The retention spring 310, 410 may be comprised of a metallic or bimetallic material (e.g., titanium), a metallic composite material, or a non- metallic, synthetic material (composite and or plastic and / or polymer). In some preferred embodiments, the retention spring may be formed of a negative thermal expansion material such as, e.g., Zirconium tungstate (ZrW₂O₈). Zirconium tungstate has the property that it expands when cooled. This allows construction of an implant that more closely approximates the tactile and response characteristics of a real nipple. When exposed to a relative cooler temperature, the reconstructed nipple would expand. Such a material may be used alone or in combination with some other material for the implantable device itself, and shall not be limited to use solely as the spring's material of construction. [0036] The cross section of a retention spring 310, 410 can be circular, elliptical or of any suitable cross sectional construct. The shape of a retention spring 310, 410 may be conical or cylindrical, although those skilled in the art will realize and understand, upon reading this description, that other shapes are also possible and are within the scope of the invention.

[0037] The retention spring 310, 410 may be wound within the boundary separating the outer chamber from the internal containment chamber of an implantable nipple prosthetic device.

[0038] The retention spring may be fully contained within the internal containment chamber of an implantable nipple prosthetic device. [0039] An implantable nipple prosthetic device is not limited to the use of a retention spring for its memory profile characteristics, and those skilled in the art will realize and understand, upon reading this description, that other and / or different mechanisms that impart a restoring force, similar to that inherent in a spring are possible.

[0040] An implantable nipple prosthetic device that is built according to a multiple chamber design contains one or more internal chamber orifices to allow for movement of the contents of one chamber into another chamber. E.g., in the two-chamber device shown in Figs. 4(a)-4(b) an orifice 408 connects the first chamber 402-1 to the second chamber 402-2. The internal chamber orifice 408 regulates the speed and overall displacement of the response as illustrated in Figs. 3(b) and 4(b). As shown in Fig. 4(b), the viscous fluid 406 transfers from one chamber (second chamber 402-2) of the containment to the other chamber (first chamber 402-1) as the result of an external force. As the force is released, the fluid returns to its source location and the device regains its initial overall length / profile, resultant of the internal retention spring 410 as illustrated in Fig. 4(a). Similarly, for the device shown in Figs. 3(a)-3(b), upon application of an external force the viscous fluid 306 transfers from one part of the chamber of the containment to the rest of the chamber. As the force is released, the fluid returns to its source location and the device regains its initial overall length / profile, resultant of the internal retention spring 310 as illustrated in Fig. 3(a).

[0041] In order to allow for compression of the device, one or more chambers (not shown) may be formed on the device (e.g., on one or more sides), to allow the device to bulge around the periphery.

[0042] In an embodiment of the implantable nipple prosthetic device, as defined by the current invention, the material selection, internal containment configuration, fluid density, fluid viscosity, resultant damping constant and spring constant are preferably tuned to provide a response envelope which imitates that of a natural nipple when surgically implanted.

[0043] Another embodiment of an implantable nipple prosthetic device is shown in Figs. 5(a)-5(d) which show a device 500 using a plurality (e.g., 12 in the drawings) of longitudinal ribs (denoted 502-/) and at least one latitudinal rib 504.

The construct of the ribs is of a preferably circular cross section. The ribs are preferably solid and may be formed of (or may contain) a negative thermal expansion material such as, e.g., Zirconium tungstate (ZrW₂Og). The ribs may, e.g., be formed around a frame comprising a negative thermal expansion material.

The device shall preferably be manufactured of material(s) which are biologically inert and non toxic.

[0044] While twelve longitudinal ribs are shown in the drawings, those skilled in the art will realize and understand, upon reading this description, that a different number (fewer or greater) of ribs may be used.

[0045] In preferred embodiments, the implant will return to its original state when released from a compressed state.

[0046] In one preferred embodiment, the overall resting diameter of the implant is 0.375 inches, the longitudinal rib diameter is 0.0175 inches, and the latitudinal rib diameter is 0.0175 inches. However, those skilled in the art will realize and understand, upon reading this description, that different sized implants are needed, e.g., for different sized breasts and/or in order to match a natural nipple that is not being reconstructed. Accordingly, an implantable nipple prosthetic device may be made in a number of different sizes.

[0047] The present invention provides a surgical ly-implantable nipple prosthetic device that has comfort as well as tactile and aesthetically enhancing elastic-return properties which improve upon prior art nipple prostheses at least in the following manner: The device's overall height can be substantially reduced without a substantial increase in diameter when an external load, e.g., a compressive force, is applied. The device returns to its original shape and size when the load is removed.

[0048] This result is accomplished by providing an internally supportive construct that maintains the integrity, shape, appearance and tactile feel of the reconstructed nipple. The use of the implant described here results in a prosthetic

/ reconstructed nipple that, when employed as specified, better approximates the appearance and feel of a natural nipple when compared to prior art implantable nipple prostheses.

[0049] A surgically implantable nipple prosthetic device, having comfort and aesthetic enhancing elastic-return properties, is presented. The implantable nipple prosthetic device improves upon prior art prostheses in that the device is substantially reduced in overall height when an external load, e.g., a compressive force, is applied and in that the device recovers its original shape and size when the load is removed.

[0050] Exemplary embodiments have the following features and / or characteristics:

[0051] An implantable nipple prosthetic device is a specifically sized, sealed and sterilized device of an inert synthetic construction, which is comprised of, but not limited, to silicone, plastic, polymer, or a composite / combination composition. [0052] According to exemplary embodiments, an implantable nipple prosthetic device can be characterized as being a multi ribbed structure with ribs of varying cross section and cross sectional profile.

[0053] An implantable nipple prosthetic device is a purpose built-construct that forms a compliant backing, which has a memory-profile that maintains the shape and projection the reconstructed nipple. Key to the memory-profile is the number and characteristics of the ribbed structure which shall impart a specified constant and accommodate a tuned response as well as position memory to the implantable nipple prosthetic device.

[0054] In an exemplary method, an implantable nipple reconstruction device, as defined by the current invention, is placed within a pocket or cavity of tissue on a breast mound that is created from incised local flaps of skin and fat that are elevated from the breast mound to create the cavity. This device is placed inside or underneath the reconstructive substrate tissue during surgery and remains as a permanent implant.

[0055] One of ordinary skill in the art will realize, upon reading this description, that other methods or techniques for forming a cavity within the breast tissue are possible, including methods that allow a surgically implantable nipple reconstruction device, as defined by the present invention, to be placed underneath and / or through the pectoral muscle.

[0056] Thus is described a surgically implantable nipple prosthetic device and a method of using the same. While the invention has been described in connection with several example embodiments, it should be understood that the invention is not limited by the disclosed examples, but on the contrary, is intended to cover various modifications and equivalent arrangements.

PROSTHETIC BREAST

[0057] Breast mound reconstruction, following a mastectomy procedure to treat breast cancer, is the first stage of the breast reconstruction process whereby a liquid implant, such as saline or silicone, is typically used to form the breast mound. Such prior art breast implants are typically positioned under the pectoral muscle in an attempt to better conceal the devices given the very limited amount of remaining breast tissue following a mastectomy. In spite of such care, liquid filled implants when used in the breast reconstruction process are prone to folding, rippling, and rupture.

[0058] A surgically implantable non-liquid, ribbed breast reconstructive device, having comfort and aesthetic enhancing elastic-return properties that result in a breast implant that maintains its shape and position and is not prone to leakage if ruptured is presented.

[0059] Figures 7(a)-7(b) show top and side views, respectively, of an exemplary embodiment of a ribbed breast implant. The ribbed breast implant is a specifically sized, sealed and sterilized device of an inert synthetic construction, which is comprised of, but not limited, to silicone, plastic, polymer, or a composite/combination composition. According to exemplary embodiments, a ribbed breast implant is a multiple ribbed structure with ribs of varying cross section and cross sectional profile, which have a memory-profile that maintains the shape and position of the reconstructed breast. Key to the memory profile is the number and characteristics of the ribbed structure which shall impart a specified constant (-KX) and accommodate a tuned response as well as position memory to the ribbed breast implant device. In an exemplary embodiment the specified constant (-KX) is tuned to provide a response envelope which imitates that of a natural human breast when surgically implanted, although it is not limited to this value.

[0060] In an exemplary method, the ribbed breast implant is placed underneath the pectoral muscle to form the reconstructed breast mound. [0061] Those skilled in the art will realize and understand, upon reading this description, that the prosthetic devices described herein may be used for reconstructive and/or cosmetic purposes, and their use is not limited to either purpose. •

[0062] Those skilled in the art will realize and understand, upon reading this description, that the prosthetic nipples and breasts described herein may be used alone or in combination.

[0063] While certain configurations of structures have been illustrated for the purposes of presenting the basic structures of the present invention, one of ordinary skill in the art will appreciate that other variations are possible which would still fall within the scope of the appended claims. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

CLAIMS WE CLAIM

1. An implantable prosthetic nipple comprising a material having a negative thermal expansion.

2. An implantable prosthetic nipple as in claim 1 comprising:

a plurality of longitudinal ribs integrally formed with at least one latitudinal rib to form a substantially spherical shape.

3. An implantable prosthetic nipple as in claim 2 comprising: twelve longitudinal ribs.

4. An implantable prosthetic nipple as in claim 3 consisting of exactly one latitudinal rib.

5. An implantable prosthetic nipple as in claim 2 wherein a cross- sectional portion of each of the longitudinal ribs is substantially circular.

6. An implantable prosthetic nipple as in claim 1 wherein the at least one of the longitudinal ribs comprises the material having a negative thermal expansion.

7. ^■ An implantable prosthetic nipple as in claim 5 wherein the material comprises Zirconium tungstate (ZrW₂Og).

8. An implantable prosthetic nipple as in claim 1 wherein the material comprises Zirconium tungstate (ZrW₂O₈).

9. An implantable prosthetic nipple comprising: a plurality of longitudinal ribs integrally formed with at least one latitudinal rib to form a substantially spherical shape.

10. An implantable prosthetic nipple as in claim 1 comprising: at least one chamber containing a liquid, and a retention spring constructed and adapted to allow compression of the nipple and to return the nipple to a relaxed state upon release of compression.

11. An implantable prosthetic nipple as in claim 10 wherein the spring comprises a material selected from the group comprising: a metallic material, a metallic composite material, a non-metallic, and a synthetic material.

12. An implantable prosthetic nipple as in claim 10 wherein the retention spring comprises the negative thermal expansion material.

13. An implantable prosthetic nipple as in claim 10 comprising: two chambers connected via at least one hole which allows said liquid to flow between said chambers.

14. An implantable prosthetic breast comprising a plurality of longitudinal ribs integrally formed with at least one latitudinal rib.

15. An implantable prosthetic breast as in claim 14 wherein the ribs are comprised of a material selected from the group comprising:

silicone, natural rubber, plastic, polymer, or a composite material.

16. An implantable prosthetic breast as in claim 14 wherein the plurality of ribs are covered by an outer layer comprised of a material selected from the group comprising: silicone, natural rubber, plastic, polymer, or a composite material.