Surface modified viscoelastics for ocular surgery

1. A method of performing ophthalmic surgery comprising:

during capsulorhexis of a capsular bag, instilling a hyaluronate-based viscoelastic agent into the site of the surgery;

introducing a polymer-containing irrigating solution into the site of the surgery so that it makes contact with the viscoelastic agent along an interface;

permitting the irrigating solution to mix with the viscoelastic agent at the interface thereby reducing the cohesiveness of the viscoelastic agent along the interface; and

removing said viscoelastic before closing the capsular bag.

2. The method of claim 1 , wherein the hyaluronate-based viscoelastic is an aqueous solution of sodium hyaluronate having an average molecular weight greater than 750,000 Daltons and a concentration of from about 0.5% to about 3% by weight.

3. The method of claim 1 , wherein the polymer-containing irrigating solution contains a polymer having an average molecular weight of less than 500,000 Daltons, which polymer is selected from the group consisting of: HA, CS, polyacrylamide, HPMC, proteoglycans, collagen, methylcellulose, carboxymethyl cellulose, ethylcellulose, hydroxyethyl cellulose, polyvinylpyrrolidone, keratin, carrageenans, and pharmaceutically acceptable salts and combinations thereof.

4. The method of claim 3 , wherein the polymer-containing irrigating solution contains chondroitin sulfate at a concentration of from about 0.5% to about 7% by weight.

5. The method of claim 4 , wherein the concentration of the chondroitin sulfate in the irrigating solution is from about 2% to about 5% by weight and the chondroitin sulfate has an average molecular weight of from about 20,000 to about 80,000 Daltons.

6. The method of claim 3 , wherein the polymer-containing irrigating solution contains hydroxypropylmethyl cellulose at a concentration of from about 0.05% to about 5.0% by weight.

7. The method of claim 4 , wherein the concentration of the hydroxypropylmethyl cellulose in the irrigating solution is from about 0.1% to about 0.5% by weight and has an average molecular weight of from about 50,000 to about 200,000 Daltons.

8. The method of claim 1 , wherein said permitting the irrigating solution to mix with the viscoelastic agent at the interface comprises mixing using ultrasonic waves.

9. The method of claim 8 wherein said mixing takes place during phacoemulsification.

10. The method of claim 3 wherein the polymer-containing irrigating solution contains hydroxypropylmethyl cellulose at a concentration of from about 0.05% to about 5.0% by weight and chondroitin sulfate at a concentration of from about 0.5% to about 7% by weight.