Menstrual cycle-dependent differences between right and left visual hemifields in perimetry

Purpose: To evaluate the effect of the menstrual cycle and gender on right and left visual hemifields in healthy subjects. Methods: One randomly selected eye from each of 42 healthy normally menstruating women and of 37 men with no systemic and ocular problems, other than refractive error, were included in the study. Subjects underwent complete ocular examination and standard acromatic perimetric (SAP) and short-wavelength automated perimetric (SWAP) analysis in both follicular (7th to 10th day of the cycle) and luteal phases (days 3 to 7 before the menstrual bleeding) of the menstrual cycle. Visual field analysis was performed using Model 750 Humphrey Field Analyzer II (Carl Zeiss Meditec, Dublin, CA, USA) with full-threshold, central 30-2 program. Results: The mean age of female (n = 42) and the male subjects (n = 37) were 35.2 +/- 3.1 years and 34.8 +/- 2.9 years, respectively (p = 0.58). Neither females nor males showed any statistically significant differences in the right and left hemifield tests with SAP (both p values > 0.05). However, using SWAP, in luteal phase of female subjects, left hemifield sensitivity was significantly less than (with a mean of 0.47 dB) right hemifield. In follicular phase, there was no significant interhemifield difference (p > 0.05). Male subjects did not show any significant differences between the sensitivity of the two hemifields with SWAP tests. Conclusions: There has been a significant difference between the mean SWAP sensitivity of right and left visual hemifields in luteal phase of the menstrual cycle. In case of a suspected hemifield difference, SAP rather than SWAP may be used to confirm suspected neurological defects as SAP is not affected by the menstrual cycle.