Neurovisual rehabilitation in cerebral blindness.

Abstract

The efficacy of a systematic training of saccadic eye movements was evaluated in hemianopic patients with three main objectives: (1) to determine the role of visual field recovery, (2) to assess the transfer of treatment gains to functional outcome measures, and (3) to evaluate the patients' subjective experience throughout therapy. Within-subject repeated measures design. The mean follow-up interval was 3 months (range, 1 to 10 months). Outpatients of a day clinic for the treatment of neuropsychological disorders that is associated with a city hospital. A consecutive sample of 22 hemianopic patients without neglect after unilateral stroke. Follow-up was possible in all cases. Saccadic eye movement strategies were treated regularly (30-minute daily sessions 5 days per week; 25 to 27 total treatment sessions). Visual perimetry results, visual search field within the scotoma, visual search on projected slides with wide eccentricity, search times for identifying objects visually on a table (table test), and standardized rating of the degree of subjective visual impairment due to the field defect. All outcome measures were planned before initiation of the study. (1) Increase in visual search field size (mean, 30 degrees). (2) Training-related visual field increases in 12 (54%) of 22 patients (mean increase, 6.7 degrees; range, 2 degrees to 24 degrees). (3) Transfer of treatment gains to functional measures (table test) and improvement after training in patients' subjective rating of their visual impairments. (4) Stability of improvements at the 3-month follow-up visit. (5) Return to part-time work in 20 (91%) of 22 patients. All mentioned results were significant (nonparametric tests; alpha level, .05; two-sided; adjusted for the number of tests). Training of compensatory eye movement strategies restores oculomotor functions, improves performance in functional visual activities, and reintegrates hemianopic patients into vocational life.