CONTRAST SENSITIVITY IN BENIGN INTRACRANIAL HYPERTENSION

A study was undertaken to assess contrast sensitivity impairment in pa tients with benign intracranial hypertension (BIH) and to determine if contrast sensitivity provides more information about visual dysfuncti on than Snellen visual acuity. A computer-based system was used to mea sure spatial contrast sensitivity for chromatic and luminance stimuli at I, 4, and 16 cycles per degree (c/deg). The results from 26 eyes of 15 patients with BIH were compared with those of a control group matc hed for age and visual acuity. The visual acuity in the BIH group was normal (6/6 or better) in 22 eyes (85%) and slightly reduced (6/9) in the remaining four eyes (15%) Contrast sensitivity was significantly r educed in the BIH group at all spatial frequencies both for chromatic and luminance measures. In addition, there was a significantly greater loss of luminance compared to chromatic contrast sensitivity at low s patial frequency (I c/deg). Contrast sensitivity measures are more sen sitive than Snellen visual acuity in assessing BIH-related visual loss and may be of value in the initial assessment and followup of these p atients.