Flexible seamless memory tissue expanding implant

• US 6,315,796 B1
• Filed: 05/13/1999
• Issued: 11/13/2001
• Est. Priority Date: 05/13/1999
• Status: Expired due to Fees

• Current Assignee: The Board of Trustees of the University of Arkansas (University of Arkansas System)
• Original Assignee: The Board of Trustees of the University of Arkansas (University of Arkansas System)
• Inventors: Eaton, L. Daniel
• Primary Examiner(s): Willse, David H.
• Application Number:
  US09/311,825
• Time in Patent Office: 915 Days
• Field of Search: 623/7, 623/8, 623/23.67, 623/23.68, 623/23.71, 604/43
• US Class Current: 623/8
• CPC Class Codes: A61F 2/02 Prostheses implantable into the body closure means for urethra or rectum or for artificial body openings therefor A61F2/0004
• CPC Class Codes: A61F 2/12 Mammary prostheses and implants

Abstract

A flexible, seamless tissue expanding implant with predetermined memory shape to augment tissue for accurate anatomical restoration for alloplastic reconstruction. The implant is a hollow shape formed from a material that tends to resume its molded shape even when collapsed and when reinflated resumes the desired shape. A minimal incision is made in the patient. From the incision a pocket is formed under the skin of the patient. The pocket is sized to hold the implant, which is inserted, in a collapsed deflated condition. The incision is then closed and allowed to heal. The implant is provided with a one-way, self-sealing valve for periodic inflation. The one-way valve is a latex plug encapsulated with silastic and incorporated into the implant. The valve can be palpated by the surgeon so that inflation can be performed with the implant in place by inserting a hypodermic needle through the skin of the patient, through the valve and into the interior of the implant. The implant is injected with the filling material at periodic intervals so that the tissue is gradually expanded to the appropriate extent. Since the implant has previously been formed into the desired shape, the implant gradually assumes the predetermined shape as it is filled. Therefore, the tissue likewise assumes the desired shape and predetermined volume augmenting the deficient anatomy predictably.

Claims

1. A tissue expanding shape memory implant for augmenting tissue for restoration of an anatomical feature, comprising:

a fluid-tight hollow envelope molded into a predetermined shape replicating the anatomical feature; and

a self-sealing valve molded into said hollow envelope;

said fluid-tight envelope comprising walls of a material capable of being deflated for compression into a minimum volume for implantation under said tissue;

said walls having sufficient stiffness and structural memory to recover said predetermined shape after being deflated and upon periodic inflation assuming said predetermined shape while gradually augmenting said tissue; and

wherein said predetermined shape further comprises a protuberance capable of being palpated through the tissue of a patient and said self-sealing valve is incorporated in said protuberance.

2. The tissue expanding implant of claim 1 wherein said self-sealing valve comprises a plug of latex incorporated within said walls of said fluid-tight envelope.

3. The tissue expanding implant of claim 2 wherein said material comprising said walls comprises room temperature vulcanizable silicone.

4. The tissue expanding implant of claim 3 wherein said predetermined shape replicates a breast.

5. The tissue expanding implant of claim 4 wherein said protuberance substantially replicates a breast nipple and areola.