METHODS: Totally 28 standard rabbits were selected with right eyes operated for vitrectomy, and then, they were randomized into three groups: Group A 12 rabbis, Group B 12 rabbits, Group C 4 rabbits. Group A: vitreous body was cut-down and filled with silicon oil; Group B: vitreous body was cut-down and filled with heavy silicon oil; Group C: vitreous body was cut-down and filled with BSS. Taken into account were the experimental animals' different periods thickness of the retinal, intraocular pressure and ERG b-wave amplitude for statistical analysis.

RESULTS: Comparison between any two means of Group A, B or C surgery eyes' preoperative and postoperative at different time points: measured IOP showed no significant difference(P> 0.05); the retinal thickness mean value measured by OCT had statistically significant(P<0.05)at the postoperative 24wk; there was a conspicuous statistically significant(P<0.01)of ERG'sb-wave amplitude at the postoperative 24wk.

CONCLUSION: As the stuffing of vitreous cavity, the silicone oil or heavy silicone oil has no obvious difference to the influence of intraocular pressure for medium to longer term. But heavy silicone oil has more serious negative impact of retinal visual information transmission function, more significantly reduce of retinal thickness than ordinary silicone oil in the longer term.