CONTRAST SENSITIVITY IN DIABETIC PREGNANCY

Purpose: To evaluate the correlation between the changes in contrast s ensitivity and retinopathy throughout pregnancy in diabetic women with mild background diabetic retinopathy. Methods: Contrast sensitivity ( Vistech 6500 Contrast Test System) was measured in 22 type I diabetic women with mild background retinopathy [0-16 microaneurysms (MAs)/eye and occasional small intraretinal hemorrhages] and 10 healthy pregnant women at the 12th and 32nd weeks of pregnancy and 3 months after deli very. Red-free fundus photography was also performed at all visits. Re sults: Throughout pregnancy contrast sensitivity was lower in the diab etics than in the controls at 1.5, 3.0, and 6.0 cycles per degree (cpd ). During the course of pregnancy, contrast sensitivity decreased at 1 .5 and 6.0 cpd in patients with more than five new MAs compared to tho se with fewer than five new MAs during pregnancy. Likewise, contrast s ensitivity decreased at 6 cpd in patients with an increase in MA count during pregnancy and at 6 and 12 cpd in patients with a baseline MA c ount of two or more MAs. Conclusions: Contrast sensitivity, especially at low to mid-range spatial frequencies, is decreased in diabetic wom en with mild retinopathy. Even small changes in retinopathy are reflec ted in a decrease in contrast sensitivity during and after pregnancy. Thus, contrast sensitivity seems to be a sensitive indicator of change s in minimal background retinopathy.