NATURAL COURSE OF VISUAL FUNCTIONS IN THE BARDET-BIEDL SYNDROME

Objective: To determine the course of visual functions in patients wit h Bardet-Biedl syndrome. Patients and Methods: The 21 patients with Ba rdet-Biedl syndrome seen at Children's Hospital, Boston, Mass, had opt otype and grating acuities and dark-adapted thresholds measured over t ime. Their ages at first visit ranged from 2 weeks to 23 years (median age, 6 years). The courses of the visual functions were analyzed with a random-effects model. Results: Substantial declines in visual funct ions were found. On average, grating and optotype acuities declined 0. 09 log units (roughly 1 line) per year, and thresholds increased about 0.19 log units per year. The rates at which these visual functions we re lost and the predicted level of the visual functions at ages 11 to 12 years (the mean ages of measurement) varied among individuals.Concl usions: The visual prognosis for children with Bardet-Biedl syndrome i s poor. The course of both central and peripheral visual functions is variable.