Although pre-operative retinopathy severity appears to be a major fact
or in determining the visual outcome of diabetic extracapsular catarac
t extraction, its precise relationship to post-operative visual acuity
is ill defined. A meta analysis was therefore carried out, and studie
s were included if pre-operative maculopathy and retinopathy status wa
s sufficiently defined to permit discrimination of visual outcome betw
een subgroups. Weighted mean proportions of eyes achieving a postopera
tive visual acuity greater than or equal to 6/12 were as follows: no r
etinopathy, 87%; non-proliferative retinopathy with no maculopathy, 80
%; quiescent proliferative retinopathy with no maculopathy, 57%; non-p
roliferative retinopathy with maculopathy, 41%; quiescent proliferativ
e retinopathy with maculopathy, 11%; active proliferative retinopathy,
0. Differences in visual outcome between groups were significant (chi
(2) = 119.9, p<0.0005), attributable mostly to the trend across groups
(chi(2) for trend = 115.4, p<0.0005). Logistic regression indicated t
hat maculopathy was a more potent predictor of post-operative visual a
cuity less than or equal to 6/12 (odds ratio 6.4, 95% CI 4.13-9.94, p<
0.0005) than quiescent proliferative retinopathy (odds ratio 3.33, 95%
CI 2.04-5.42, p<0.0005). The severity of retinopathy and maculopathy
prior to cataract surgery in diabetics are the major determinants of p
ost-operative visual acuity. Further study of the relationship between
pre-operative retinopathy severity and the incidence of post-operativ
e complications, progression of retinopathy and maculopathy is require
d to optimise the management of cataract in diabetes.