OPHTHALMOLOGIC EXAMINATION OF PATIENTS WITH SEASONAL AFFECTIVE-DISORDER, BEFORE AND AFTER BRIGHT LIGHT THERAPY

PURPOSE: We assessed the potential ocular hazards of bright light ther apy for patients with seasonal affective disorder, after both short- a nd long-term treatment, and identified prospective patients with pre-e xisting ocular abnormalities. METHODS: Fifty patients with seasonal af fective disorder received daily exposure to artificial light in the mo rning or evening for 30 minutes at an illuminance level of 10,000 lux (irradiant dose, 0.016 J/cm(2)). Ophthalmologic examinations were perf ormed before and after short term treatment (two to eight weeks) and a fter three to six years of use during the fall and winter months. Over the four years of patient intake, the eye examination included subset s of the following tests: visual acuity, intraocular pressure, slit-la mp biomicroscopy, direct and indirect ophthalmoscopy, color vision, vi sual field, fundus photography, Amsler grid, ocular motility, pupillar y reactions, contrast sensitivity, stereopsis, and the macular stress test. RESULTS: No ocular changes were detected after short-term treatm ent. Long-term treatment (three to six years) of 17 patients, with cum ulative exposure durations of 60 to 1,250 hours, also resulted in no o cular abnormalities. CONCLUSIONS: Light therapy yields about 75% clini cal remissions. It is effective as an antidepressant and appears safe for the eyes. Current knowledge is insufficient to specify any definit e ocular contraindications for bright light therapy, although we recom mend that patients with pre-existing ocular abnormalities and those us ing photosensitizing drugs undergo treatment only with periodic ophtha lmologic examination.