Twelve patients with pseudotumor cerebri underwent sensory visual testing and the results were analyzed. Contrast sensitivity loss was detected with use of Arden gratings in nine of the twelve patients (75%) and in 13 of 24 eyes (54%). Snellen acuity was worse than 20/20 in 21% of eyes. Contrast sensitivity scores improved with resolution of the patient's papilledema whereas there was no significant improvement of Snellen acuity. Contrast sensitivity testing with Arden plates is a useful procedure for detecting visual loss and serially following patients with pseudotumor cerebri.