EFFECTS OF PHYSIOLOGIC CHANGES IN ESTRODIOL HORMONE ON RETINA AND OPTIC NERVE FUNCTION, VASCULARIZATION AND STRUCTURE IN HEALTHY WOMEN.

Purpose: This study aimed to investigate the effects of estrodiol changes occurring during the first follicular phase of the menstrual cycle on retinal and optic nerve functions, vascularity and structure in healthy adults using pattern electroretinography (PERG), optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA).

Evaluation of the effect of estrogen hormone changes on retinal and optic nerve functions, vascularity and structure during the follicular phase of the menstrual cycle using optical coherence tomography, optical coherence tomograph angiography and pattern electroretinography.

Methods: The study included 26 healthy subjects with a visual acuity of 1.0. Parameters such as serum hormone levels, intraocular pressure (IOP), cycloplegic spherical equivalent (SE), pERG, retinal nerve fiber layer (RNFL) thickness and OCTA measurements were evaluated.

 The PERG tests were performed using the Metrovision brand monpack model device. Spectral-domain OCT (Topcon Corporation, Tokyo, Japan); OCTA (Optovue, Inc, Fremont, CA) system was used. Tests were conducted on the 1st and 14th days of the menstrual cycle, and the data were compared.

Results: The mean serum estradiol values ​​on the 1st and the 14th day were measured as 51+ 19 ng/L and 304 +  50 ng/L respectively  PERG revealed no statistically significant differences in the amplitude and latency of the P50 and N95 waves between days 1 and 14. RNFL thickness did not differ significantly in the mean, upper, or lower quadrants between days 1 and 14 of the menstrual cycle (p=0.90, p=0.85, and p=0.39, respectively). In OCTA analysis, peripapillary and macular vascular density values ​​were similar between days 1 and 14 (p>0.05). Correlation analysis revealed no significant relationship between electrophysiological parameters, RNFL thickness measurements, and retinal vascular densities (p>0.05).

Conclusion: In healthy women, no significant functional, vascular, or structural differences were observed in pERG, OCT, or OCTA parameters between low and high estradiol levels between days 1 and 14 of the menstrual cycle. Unlike the persistent low estradiol levels seen in menopause, changes in estradiol during a healthy menstrual cycle do not cause functional, structural, or vascular changes in the optic nerve and retina.