Prosthesis with improved biocompatibility made with N-vinyl polymers

• US 5,713,960 A
• Filed: 10/16/1996
• Issued: 02/03/1998
• Est. Priority Date: 07/06/1991
• Status: Expired due to Fees

• Current Assignee: Cystomedix, Inc.
• Original Assignee: James Marlow Christensen, Parviz Robert Ainpour
• Inventors: Ainpour, Parviz Robert, Christensen, James Marlow
• Primary Examiner(s): Prebilic, Paul B.
• Application Number:
  US08/734,407
• Time in Patent Office: 475 Days
• Field of Search: 623/4, 623/8, 623/11, 623/15, 623/1, 523/113, 523/115
• US Class Current: 523/113
• CPC Class Codes: A61F 2/12 Mammary prostheses and implants
• CPC Class Codes: A61L 27/16 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: C08L 39/06 Homopolymers or copolymers of N-vinyl-pyrrolidones

Abstract

An injectable or implantable material for soft tissue augmentation comprising a hydrogel containing both hydrophobic and hydrophilic domains is prepared by copolymerizing a hydrophilic monomer, such as water soluble N-vinylpyrrolidone with non-water soluble monomers, such as N-vinyl carbazole, its derivatives, or a non-water soluble derivative of N-vinylpyrrolidone. Also suitable for injection into direct contact with body tissue are hydrogels prepared by cross-linking polyvinylpyrrolidone. The hydrogel may be either solid or composed of particles. The hydrogel may also be enclosed within a flexible porous or nonporous envelope.

Claims

1. A hydrogel for placement in contact with body tissue within a mammalian body to replace or augment tissue or body fluids:

said hydrogel consisting of N-vinyl pyrrolidone and an N-vinylic hydrophobic monomer reacted to form a polymer having hydrophilic and hydrophobic domains.

2. The hydrogel of claim 1 wherein the hydrophobic domains of the hydrogel are held together with hydrophobic bonding, ionic bonding, dipolar bonding, hydrogen bonding or a combination of these forces.

3. The hydrogel of claim 1 wherein the hydrogel is prepared by the copolymerization of a hydrophilic monomer with an N-vinylic hydrophobic monomer.

4. The hydrogel of claim 1 wherein the water concentration of the fully hydrated hydrogel is from about 40% by weight to about 99% by weight.

5. The hydrogel of claim 1 wherein the water concentration of the fully hydrated hydrogel is greater than about 85% by weight.

6. The hydrogel of claim 4 wherein the hydrogel can be passed through a 30 gauge needle.

7. The hydrogel of claim 1 wherein the hydrogel is suspended in a physiological solution for placement in a mammalian body.

8. The method of reconstructing or augmenting the tissue of a mammalian body comprising the placement of a hydrogel polymer in contact with body tissue,

said hydrogel consisting of N-vinyl pyrrolidone and an N-vinylic hydrophobic monomer reacted to form a polymer having hydrophilic and hydrophobic domains, the hydrogel polymer when fully hydrated capable of filling a space within the body tissue.

9. The process of claim 8 wherein the hydrogel is mixed with a sufficient quantity of an aqueous solution to fully hydrate the hydrogel.

10. The process of claim 9 wherein the fully hydrated polymer is placed in the desired location in the body by passing it through a tubular device inserted into the body.

11. The process of claim 9 wherein the fully hydrated polymer is shaped into a desired form and the desired form is surgically inserted into the body.

12. The process of claim 8 wherein the hydrogel is placed in the body in a less than fully hydrated state.

13. The process of claim 12 wherein the hydrogel is dehydrated before placement in the body.

14. The process of claim 13 wherein the hydrogel is formed into a shape such that when fully hydrated the hydrogel will expand to a desired final dimension.

15. The process of claim 13 wherein the hydrogel is powdered, dispersed in a physiological solution and placed into the body through a tubular device inserted into the body.

16. The process of claim 13 wherein the hydrogel is formed into a shape and placed into the body through a tubular device inserted into the body.

17. A hydrogel for placement in contact with body tissue within a mammalian body to replace or augment tissue or body fluids:

said hydrogel consisting of a polymer having hydrophilic and hydrophobic domains,

the hydrophilic domain being derived from a water soluble monomer of N-vinylpyrrolidone or a vinylic compound of the formula ##STR5## wherein R is H or CH₃ R'"'"' is CH₂ --CH₂ --OH, CH₂ --CH(CH₃)--OH or CH₃ --CH(OH)--CH₂ --OH and R" and R'"'"'" are H, CH₃ C₂ H₅ or CH₂ --CH(OH)--CH₃

the hydrophobic domain

a) being derived from a non-water soluble monomer of the formula

space="preserve" listing-type="equation">RR'"'"'--N--CH═

CH.sub.2

where R is H or CH₃ and R'"'"' is CH₃, CH₂ --CH₃ or higher alkyls, or an aromatic group or

b) is selected from the group consisting of N-vinyl carbazole, N-vinylphthalimide and its derivatives, non-water soluble derivatives of N-vinylpyrrolidone, and aromatic derivatives of N-vinylpyrrolidone.

18. The hydrogel of claim 17 wherein the hydrophobic monomer is selected from the group consisting of N-vinyl carbazole, derivatives of N-vinyl carbazole, non-water soluble derivatives of N-vinylpyrrolidone and aromatic derivatives of N-vinylpyrrolidone.

19. The hydrogel of claim 18 wherein the derivative of N-vinyl carbazole, the non-water soluble derivatives of N-vinylpyrolidone and aromatic derivatives of N-vinyl pyrrolidone includes a pendant group selected from the group consisting of oxygen, halogen, and alkyls.

20. The hydrogel of claim 17 wherein the water concentration of the fully hydrated hydrogel is from about 40% by weight to about 99% by weight.

21. The hydrogel of claim 17 wherein the water concentration of the fully hydrated hydrogel is greater than about 85% by weight.

22. The hydrogel of claim 17 wherein the hydrogel can be passed through a 30 gauge needle.

23. The hydrogel of claim 21 wherein the hydrogel is suspended in a physiological solution for placement in a mammalian body.