A study of contrast sensitivity in hypertension disorders caused by a complication of pregnancy and the resulting changes in the fundus

Abstract

Objective To study contrast sensitivity (CS) in hypertensive disorders caused by a complication of pregnancy and the changes in the fundus during the follow-up period. Methods A prospective cohort study was applied to the research, ninety-eight patients with hypertensive disorders as a complication of pregnancy(the patient group) agreed to undergo eye examinations that included visual acuity, fundus examinations, and CS evaluations. Patients were followed up for 6 months and visual acuity and CS changes were monitored. Fifty pregnant women were selected as a control group during the same period. The corrected visual acuity for the two groups and the CS at each spatial frequency were compared with two independent sample t-tests. The CS of each spatial frequency in the three trimesters with retinopathy and during the follow-up was compared with a Kruskal-Wallis rank sum test. After multiple group analysis, a comparison between pairs of groups was analyzed with a Satterthwaite approximation test. Results The corrected visual acuities of patients with hypertensive disorders as a complication of pregnancy were lower than those for the normal control group at the first visit and after the six-month follow-up period (t=13.67, 2.27, P 0.05), but the other spatial frequencies were reduced (t=2.74, -5.42, -8.67, -4.60, P 0.05). Conclusion Fundus changes in patients with hypertensive disorders as a complication of pregnancy and the decrease in CS are both more serious than for normal patients. CS with the low spatial frequency had the fastest recovery and a high spatial frequency was the slowest to recover. The two kinds of delivery methods for birth have no effect on the recovery of CS. CS is a better indicator than visual acuity to reflect the function of the retina in patients with hypertensive disorders as a complication of pregnancy. Key words: Hypertension,pregnancy-induced; Retinal disease; Contrast sensitivity