Topographic change in the central macula coupled with contrast sensitivity loss in diabetic pregnancy.

Abstract

To study macular topography and contrast sensitivity (CS) in diabetic and nondiabetic women during pregnancy and post partum. A prospective study of 46 pregnant women with insulin-dependent diabetes and 11 nondiabetic pregnant controls. Macular surface topography was analyzed by Heidelberg Retinal Tomograph. Volume above the reference plane (VARP) was measured with 1.0-, 1.5-, 2.0-, and 3.0-mm-diameter circles. CS was measured with the Vistech 6500 Contrast Test System. The diabetic women had greater VARP than the controls measured with the 1.5-mm diameter circle. In diabetic women, the mean VARP was 0.084+/-0.064 mm(3) (mean +/- SD) in the first trimester, 0.080 +/- 0.056 mm(3) in the third trimester, and 0.087 +/- 0.067 mm(3) 3 months post partum compared with the values of 0.069+/-0.043, 0.054+/-0.024, and 0.036+/-0.020 mm(3) in the controls ( P=0.036 between groups). In diabetic women requiring laser treatment, the difference from controls was more significant ( P<0.001). CS at 3 cpd and 6.0 cpd was lower in diabetic women than in controls throughout pregnancy and post partum ( P=0.012 and P=0.043). A statistically significant negative correlation appeared between macular topography and CS during the third trimester; between cpd 6 and VARP 1.5 mm ( r=-0.471, P=0.001), and between cpd 6 and VARP 2.0 mm ( r=-0.446, P=0.002). In the diabetic women, especially in those with clear progression of retinopathy during pregnancy and post-partum, the macula seemed to be slightly more elevated than in the controls, and CS was lower at mid-range spatial frequencies. CS loss in the diabetic women correlated with macular elevation during the third trimester.