Lens refilling with injectable silicone in rabbit eyes.

PURPOSE

To evaluate the technique of refilling the lens capsule with injectable silicone and assess the postoperative findings.

SETTING

Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan.

METHODS

The lens capsules in the eyes of 16 rabbits weighing 1.5 to 2.0 kg were refilled with 0.2 mL of silicone polymer (about 66% bag volume) after endocapsular phacoemulsification through an upper minicircular capsulorhexis 1.5 to 1.8 mm in diameter. The capsule opening was sealed with a silicone plug to prevent leakage of the injected silicone. Main outcome measures were surgical success rate, inflammation, endothelial cell loss, refractive change after pilocarpine 4% instillation, and capsule opacification.

RESULTS

The lens capsule could be refilled in 10 eyes. The failures were caused by capsule rupture during phacoemulsification (n = 3) and profuse leakage of the injected silicone. Silicone that leaked minimally during surgery was easily washed away. Silicone that leaked and polymerized in the anterior chamber postoperatively (n = 3) was easily removed by surgery the following day. Mean endothelial cell loss was 10.2% 1 month after surgery. Aqueous flare intensity was significantly lower on days 2 and 4 than after conventional intraocular lens implantation in a control group. The respective mean preoperative and postoperative refractions were 0.7 diopters (D) +/- 1.0 (SD) and 19.1 +/- 1.0 D and the mean change (difference between the refractions before and after topical application of pilocarpine 4%), -0.4 +/- 0.6 and 1.1 +/- 0.4 D (P < .01). Posterior capsule opacification (PCO) was noted after 3 weeks in all eyes.

CONCLUSIONS

Lens capsule refilling and capsular plug use to prevent silicone leakage was shown to be feasible and avoided complications caused by leakage. Refractive changes suggest that the procedure could yield accommodation in primates> Although neodymium: YAG laser capsulotomy did not cause herniation of the injected silicone, PCO prevention is an essential issue in lens refilling because the capsulotomy may annul the attained accommodation.