Ophthalmologic examination of patients with seasonal affective disorder, before and after bright light therapy.

PURPOSE: We assessed the potential ocular hazards of bright light therapy for patients with seasonal affective disorder, after both short- and long-term treatment, and identified prospective patients with pre-existing ocular abnormalities. METHODS: Fifty patients with seasonal affective disorder received daily exposure to artificial light in the morning or evening for 30 minutes at an illuminance level of 10,000 lux (irradiant dose, 0.016 J/cm2). Ophthalmologic examinations were performed before and after short-term treatment (two to eight weeks) and after three to six years of use during the fall and winter months. Over the four years of patient intake, the eye examination included subsets of the following tests: visual acuity, intraocular pressure, slit-lamp biomicroscopy, direct and indirect ophthalmoscopy, color vision, visual field, fundus photography, Amsler grid, ocular motility, pupillary reactions, contrast sensitivity, stereopsis, and the macular stress test. RESULTS: No ocular changes were detected after short-term treatment. Long-term treatment (three to six years) of 17 patients, with cumulative exposure durations of 60 to 1,250 hours, also resulted in no ocular abnormalities. CONCLUSIONS: Light therapy yields about 75% clinical remissions. It is effective as an antidepressant and appears safe for the eyes. Current knowledge is insufficient to specify any definite ocular contraindications for bright light therapy, although we recommend that patients with preexisting ocular abnormalities and those using photosensitizing drugs undergo treatment only with periodic ophthalmologic examination.

Efficacy of brief, intense light exposure for treatment of winter depression.

A high-intensity fluorescent lighting system, tilted downward toward the head, and emitting negligible levels of ultraviolet radiation, was tested under two random crossover protocols in winter-depressed patients: 30-minute sessions at (a) 3,000 lux vs. 10,000 lux in early morning, and (b) morning vs. evening sessions at 10,000 lux. Judgment of clinical remission was based jointly on relative and absolute score improvements on a Structured Interview Guide for the Hamilton Depression Scale--Seasonal Affective Disorder Version (SIGH-SAD) and a set of supplementary atypical-vegetative items. Data are presented for 24 subjects who showed relapse upon withdrawal. An overall remission rate of 75 percent was found for morning light at 10,000 lux. The rates for evening light (25%) and 3,000 lux morning light (19%) were significantly lower. The remission rate for morning light treatment of 10,000 lux for 30 minutes approximately equalled 2,500 lux treatment for 2 hours (data from our earlier studies), suggesting a reciprocity between dosing dimensions of intensity and duration. No pathological changes were revealed by ophthalmological examinations given after 2 to 6 weeks of daily treatment.

Determination of optical penalization by vectographic fixation reversal.

Optical penalization for distance is a useful alternative to occlusion for treating amblyopia, and as maintenance therapy following occlusion. It is particularly useful in cases of patching noncompliance. The major key to patient acceptance is choosing the minimal amount of penalization necessary, while still ensuring that the patient actually switches fixation to the amblyopic eye. We have found the vectographic letter slide reliable for identifying the fixing eye for distance vision. Thirty-four patients were treated for anisometropic or strabismic amblyopia with distance optical penalization without the use of cycloplegic agents. Twenty-two patients had improvement of their visual acuity, and 10 patients remained the same during an average follow-up period of 22.5 months. The average visual acuity improved from 20/40 to 20/32. The dominant eye required an average of only +1.25 diopters of fogging for the patient to switch fixation to the amblyopic eye, significantly less than the arbitrary +3.00 diopters advocated by some clinicians.

Visual parameters associated with recovered retrobulbar optic neuritis.

Visual acuity, color vision, pupillary reaction, induced Pulfrich phenomenon, kinetic fields, static fields, afterimage testing, and ophthalmoscopic evaluation were studied in nine patients with a history of retrobulbar neuritis. The most consistently reliable test for determining the presence of an old optic nerve defect in these patients was meridional 0 to 180 degrees static perimetry. There was a uniform decrease in brightness discrimination to either side of the foveal peak.