Prevalence of Cataract in Eyes With Posterior Vitreous Detachment

Abstract

Purpose:: It was reported that there is a positive correlation between vitreous liquefaction and nuclear cataract in eye bank eyes. We investigated the correlation between posterior vitreous detachment (PVD) and three main types of cataract in Japanese and Chinese populations.

Methods:: Participants comprised 502 Japanese subjects (212 males, 290 females) aged 55 yrs and over (mean: 68.2±7.8yrs) from Monzen town (latitude 37° N), and 558 Chinese subjects (204 males, 354 females) aged 50 yrs and over (mean: 61.0±10.8yrs) from Miaolin village (latitude 18° N). After excluding aphakic and pseudophakic eyes and poor slit lamp images, 980 Japanese and 904 Chinese eyes were enrolled. Lenses were evaluated by one examiner under mydriasis using slit-lamp biomicroscopy and documented with an anterior eye segment analysis system (EAS-1000, NIDEK). Grading of cortical (C), nuclear, (N) and posterior subcapsular cataract (PSC) was performed according to the WHO simplified cataract grading system. PVD was judged as presence of Weis ring.

Results:: PVD was observed in 510 Japanese eyes (52%) and 188 Chinese eyes (20.8%) and increased with aging. There was no significant difference between sexes. Prevalences of cataract in PVD and non-PVD eyes were as follows: C, 39.6% and 38.9%; N, 9.8% and 5.3%; PSC, 2.7% and 2.6%; and cortical opacity in the central pupillary area 3mm diameter (CEN), 17.8% and 18.1% in Japanese. Prevalences in Chinese were C, 25.1% and 23.2%; N, 50.8% and 39.7%; PSC,10.2% and 11.9%; and CEN, 6.0% and 8.5%. Prevalence of N was significantly higher in PVD eyes than non-PVD. The odds ratio for N in PVD eyes against non-PVD eyes in Japanese and Chinese were 1.9 (p=0.009) and 1.6 (p=0.01), respectively (:Χ²examination). No significant difference was seen in C, PSC and CEN.

Conclusions:: Prevalence of nuclear cataract was higher in PVD eyes than in non-PVD eyes in both Japanese and Chinese populations. PVD might be a risk factor for nuclear cataract formation.

Keywords: cataract • clinical (human) or epidemiologic studies: prevalence/incidence • vitreous