Patients with macular disciform degeneration may undergo spontaneous improvement in visual acuity of the first affected eye when the second eye later undergoes a decrease in vision. Three hundred twenty-nine cases of age-related macular degeneration (AMD) and presumed ocular histoplasmosis syndrome (POH) were examined. There were 20 patients who strictly met the criteria of a disciform scar causing visual acuity of 20/200 or worse in one eye, and 20/50 or better vision in the second eye, who subsequently developed involvement of the second eye with a decrease in visual acuity to 20/200 or less. Six of these 20 patients (30%), after mean follow-up of 32.8 months, achieved spontaneous visual acuity improvement, defined as at least a five-line improvement on a decimal (logarithmic) scale, with an average increase of 7.6 lines in the first affected eye. At extended mean follow-up of 50.1 months, two of the six lost vision, so that four of the 20 (20%) had five lines or more of improvement.