Study of visual evoked potentials during normal monthly cycle in normal female subjects.

Visual Evoked potential (VEP) is one of the electrophysiological technique which is used by Neurologist and Ophthalmologist for better diagnosis of optic nerve fiber and visual cortex diseases such as Multiple Sclerosis, Optical neuritis and etc. Among the female patients used to contact the Qods electrophysiological laboratory, the authors observed the extraordinary changes in VEP pattern, which was not expected by authors, hence the research was carried out to see the possible causes of such changes. One of the trails was the physiological monthly cycle and it's possible effect on VEP pattern. For this purpose 20 normal female subjects in age group between 18-28 years were selected and they undergone VEP recording in one of ordinary and monthly cycle days, both with checkerboard pattern reversal as well as flash stimulation. The results is a proof for the changes in latency of P100 peak and the shape of VEP pattern which is reflecting more in flash than pattern reversal stimulation. Finally it is suggested to related medical specialist to take into consideration the effect of monthly cycle in recording VEP in female subject.