[Efficacy of 5-fluorouracil polyactic acid microsphere in prevention of proliferative vitreoretinopathy].

OBJECTIVE

To evaluate the efficacy of 5-fluorouracil polyactic acid microsphere in prevention of proliferative vitreoretinopathy (PVR).

METHODS

5-fluorouracil polyactic acid microsphere or 5-fluorouracil were used to implant into rabbits vitreous cavity. 48 healthy rabbits were divided into 3 groups: rabbits in Group 1 received implantation of 5-fluorouracil polyactic acid microsphere; rabbits Group 2 served as polyactic acid microsphere control; rabbits in Group 3 received only 5-fluorouracil powder. Macrophages were injected into vitreous cavity of rabbit to induce PVR. 0.2 ml BSS containing 25 mg microsphere with 2.6 mg 5-fluorouracil was injected into vitreous cavity of two eyes in Group 1. 0.2 ml BSS containing 25 mg microsphere without medicine and 0.2 ml BSS containing 2.6 mg 5-fluorouracil were injected into rabbits vitreous cavity in Group 2 and 3 respectively, Drug content in aqueous humor was measured regularly. Release feature of 5-fluorouracil polyactic acid microsphere in vivo was observed. The efficacy of the inhibition of PVR was evaluated according to Ryan's grade of proliferative vitreoretinopathy.

RESULTS

The releasing time of 5-fluorouracil polyactic acid microsphere was much longer than 5-fluorouracil powder. Its half life T(1/2) was 379.05 h with low clearance rate. The attack rate of retinal detachment in Group 2 was 62.5% and 71.9% on the 21st and 28th day respectively. The attack rate of retinal detachment in Group 3 was 64.3% and 78.6% whereas that of Group 1 was 13.3% and 13.3% on the 21st and 28th day. There was statistical difference in retinal detachment rate in Group 1 and 2 or 3 (P < 0.01). No differences was found in retinal detachment ration in Group 2 and 3 (P > 0.05).

CONCLUSION

Implantation of 5-fluorouracil polyactic acid microsphere into vitreous cavity can effectively prevent proliferative vitreoretinopathy induced by macrophages in rabbit model.