Ocular Blood Flow and Visual Function: A Comparison Between Pre and Post–Menopausal Women

Abstract

Purpose: : To compare ocular blood flow and visual function in pre and post–menopausal women.

Methods: : All procedures were approved by the Indiana University IRB, and informed patient consent was obtained. Thirty–six women were recruited for this cross–sectional study: 12 pre–menopausal (22 ± 2.9 years) and 24 post–menopausal (55 ± 3.8 years). Measurements for both groups included blood pressure (BP), heart rate (HR), visual acuity (VA), contrast sensitivity, and intraocular pressure (IOP) for both eyes. A comprehensive ocular blood flow assessment was obtained for each patient in a randomly chosen study eye. Retinal blood flow data was obtained using confocal scanning laser Doppler flowmetry Heidelberg Retinal Flowmeter (HRF). Color Doppler imaging (CDI) was used to assess retrobulbar hemodynamics in the ophthalmic, central retinal, and short nasal and temporal posterior ciliary arteries. Baseline vision and hemodynamics in pre and post–menopausal subjects were compared using paired student’s t–tests.

Results: : The pre–menopausal group had significantly lower HR (70.82 vs. 86.89; p< 0.0001) and systolic BP (119.45 vs. 137.16; p =0.003) than the post–menopausal subjects. Contrast sensitivity was significantly higher in pre–menopausal women in both the right (OD) and left (OS) eyes at 9 (OD, p=0.039; OS, p=0.001) and 18 (OD, p=0.039; OS, p=0.032) cycles/degree. The pre–menopausal women had a significantly lower IOP in both eyes (OD 12.68 ± 2.53 and OS 13.23 ± 2.02) than the post–menopausal women (14.89 ± 1.97; p=0.024 and 14.94 ± 1.95; p=0.035, respectively). Pre–menopausal women had significantly lower peak systolic (5.64 ± 0.79) and end diastolic (1.69 ± 0.18) velocities of the nasal posterior ciliary artery than the post–menopausal participants (6.78 ± 1.52; p=0.015 and 2.13 ± 0.80; p=0.034 respectively). HRF demonstrated a significantly lower inferior field 90^th percentile flow value in pre–menopausal women (550.03 ± 132.11) than post–menopausal subjects (700.73 ± 129.34; p=0.015).

Conclusions: : Pre–menopausal women presented with lower systemic BP, HR, IOP and blood flow parameters compared to post–menopausal women. Post–menopausal women had significantly reduced visual function as measured by contrast sensitivity than pre–menopausal women.

Keywords: visual acuity • contrast sensitivity • blood supply