Use of fresnel prism glasses to treat stroke patients with hemispatial neglect

OBJECTIVE: To explore the functional effects of prism adaptation training on patients with hemispatial neglect after stroke. DESIGN: Observational study. SETTING: Inpatient rehabilitation unit in rural Australia. PARTICIPANTS: Four subjects with hemispatial neglect, recruited from consecutive admissions of patients less than 60 days poststroke. INTERVENTION: Prism adaptation treatment, consisting of five 10-minute training sessions over 12 to 17 days. MAIN OUTCOME MEASURES: The FIM instrument, Catherine Bergego Scale (CBS), subjective straight ahead pointing, Albert's line cancellation, letter cancellation, and line bisection. Ambulatory patients also performed the Timed Up & Go test. RESULTS: Immediate effects of prism adaptation training included improvements in both subjective straight ahead pointing and in the Albert's line cancellation task. Letter cancellation, line bisection, FIM, and CBS scores improved in all subjects. Improvements in a functional task were also observed immediately following prism adaptation treatment. Obstacle avoidance while walking improved after prism adaptation training in 2 ambulatory subjects. CONCLUSIONS: Prism adaptation training shows promise as a new treatment to supplement current strategies for the clinical management of hemispatial neglect after stroke. This study is limited by small sample size and absence of a control group. Further research will be needed to demonstrate efficacy for this inexpensive and relatively safe device.