US5133753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for expanding a self-sealing tissue prosthesis
Assignee: Medical Engineering Corp
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Filing: 1991-08-16
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Granted: 1992-07-28
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Expires: 2011-08-16
Abstract
Abstract The self-sealing tissue expander includes inner and outer layers of relatively nonflowable material and a median layer of flowable material. The median layer of flowable material which can include one or more sublayers of flowable material is under a predetermined compression imposed by the inner and outer layers due to a prestressing of the tissue expander shell during formation of the tissue expander. The self-sealing shell seals an opening in the shell wall following removal of an infusion needle. In all embodiments of the invention a needle stop member is provided to prevent the needle that accesses the fluid chamber from passing outwardly of the tissue expander. The need for a septum, a fluid conduit or a special fluid entry opening in the tissue expander shell is thus optional. The shell can also be made relatively more stretchable in some areas than in other areas.
Inventors
- 👤 Jeffrey E. Bark
- 👤 Donald V. Hillegass
- 👤 Eric J. Woodruff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:31
CPC Classifications
B; B32; B32B; B32B25/00; B32B25/10; A; A61; A61F; A61F2/00; A61F2/02; A61F2/12; A61L; A61L27/00; A61L27/14; A61L27/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
194 words
A method of constructing and expanding an implantable tissue expander comprising the steps of: (a) forming a closed, flexible, implantable shell defining an internal chamber, the shell being substantially collapsible when the chamber is empty and expandable upon infusion of fluid into said chamber, (b) rendering substantially all of the shell self sealing with respect to needle penetration by forming inner and outer layers of relatively high durometer nonflowable material and a median layer of relatively low durometer flowable sealing material that flows into and seals a needle opening in the shell when the needle is inserted into and withdrawn from the shell, (c) prestressing substantially all of the shell such that the inner and outer layers exert a compressive force on the median layer of flowable material to force the flowable material into the needle opening in the shell when the needle is removed, (d) implanting the shell beneath stretchable tissue, (e) penetrating the shell with a needle to access the chamber and using the needle to infuse fluid directly into the chamber so as to expand the shell, and (f) removing the needle from the chamber and shell when infusion is completed.
Claim 2
Independent Claim
194 words
A method of constructing and expanding an implantable tissue expander comprising the steps of: (a) forming a closed, flexible, implantable shell defining an internal chamber, the shell being substantially collapsible when the chamber is empty and expandable upon infusion of fluid into said chamber, (b) rendering substantially all of the shell self sealing with respect to needle penetration by forming inner and outer layers of relatively high durometer nonflowable material and a median layer of relatively low durometer flowable sealing material that flows into and seals a needle opening in the shell when the needle is inserted into and withdrawn from the shell, (c) prestressing substantially all of the shell such that the inner and outer layers exert a compressive force on the median layer of flowable material to force the flowable material into the needle opening in the shell when the needle is removed, (d) implanting the shell beneath stretchable tissue, (e) penetrating the shell with a needle to access the chamber and using the needle to infuse fluid directly into the chamber so as to expand the shell, and (f) removing the needle from the chamber and shell when infusion is completed.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein the step of prestressing includes forming the shell on a curved mandrel, stripping the formed shell from the mandrel and turning the shell inside out after stripping the shell from the mandrel.
Claim 4
Dependent Claim
55 words
The method of claim 1 including completely enclosing the chamber within the shell such that there is no entry port, septum or connecting tube to communicate with the chamber and any introduction of fluid into the shell or removal of fluid from the shell must be accomplished by penetration of the shell with a needle.
Claim 5
Dependent Claim
20 words
The method of claim 1 including reinforcing the shell with a layer of polyester mesh material incorporated into the shell.
Claim 6
Dependent Claim
22 words
The method of claim 4 including heat setting the layer of polyester mesh material before incorporating said mesh material in the shell
Claim 7
Dependent Claim
17 words
The method of claim 1 including reinforcing the shell with a layer of randomly oriented polyester fibers.
Claim 8
Dependent Claim
17 words
The method of claim 1 wherein the step of implanting includes implanting the shell beneath mammary tissue.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-28 | 1996-01-27 | 1996-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-28 | 2000-01-27 | 2000-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-28 | 2004-01-27 | 2004-07-28 | $7700.00 | Window Closed / Lapsed |