Incidence of Cataract Surgery after Vitrectomy for Vitreous Opacities

Abstract

A computational model of vitreous oxygen consumption and transport predicts that limited vitrectomy will result in lower retrolental oxygen levels than extensive vitrectomy, and that higher retrolental oxygen would promote cataractogenesis. This study compared the incidence and timing of cataract surgery after limited versus extensive vitrectomy for vitreous opacities. Ninety-six phakic eyes in 75 patients (aged 55±14 years) underwent limited 25 G vitrectomy with preservation of 3 to 4 mm of retrolental vitreous and without surgical posterior vitreous detachment induction. Of these 96 eyes, 48 eyes in 37 patients (aged 56±14 years) had a minimum of 24 months' follow-up and were compared with 23 eyes from 18 patients (aged 63±8 years) who underwent extensive vitrectomy. Limited vitrectomy patients were older than extensive vitrectomy patients (P < 0.015), yet only 17 of 96 eyes (18%) required cataract surgery after limited vitrectomy (mean follow-up= 20±17 months). In eyes with a minimum follow-up of 24 months, 17 of 48 eyes (35%; age= 53-81 years) with limited vitrectomy required cataract surgery, versus 20 of 23 eyes (87%; age= 50-75 years) with extensive vitrectomy (P < 0.0001). Just before cataract surgery, visual acuity was comparable in each group (0.47±0.18 in the limited vitrectomy group vs. 0.54±0.30 in the extensive vitrectomy group; P= 0.23). Cataract surgery occurred an average of 12.4±5.1 months after limited vitrectomy, compared with 7.3±3.9 months after extensive vitrectomy (P < 0.002). The incidence of cataract surgery was lower after limited vitrectomy, which had a longer interval until cataract surgery compared with extensive vitrectomy. These findings are consistent with the computational model of oxygen consumption and transport and suggest clinical strategies to mitigate postvitrectomy cataractogenesis.