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Fresnel prisms improve visual perception in stroke patients with homonymous hemianopia or unilateral visual neglect
P W Rossi1, S Kheyfets, M J Reding
1Department of Neurology, Cornell University Medical College, Burke Rehabilitation Center, White Plains, NY.
Abstract:
We randomly assigned 39 patients with stroke and homonymous hemianopia or unilateral visual neglect to treatment with 15-diopter plastic press-on Fresnel prisms (n = 18) or to serve as controls (n = 21). Baseline evaluations of visual perception and activities-of-daily-living (ADL) function were similar for both groups. After 4 weeks, the prism-treated group performed significantly better than controls on the following: (1) Motor Free Visual Perception Test; (2) Line Bisection Task; (3) Line Cancellation Task; (4) Harrington Flocks Visual Field Screener; and (5) Tangent Screen Examination. There was no significant difference in Barthel ADL assessment at 4 weeks. Thus, treatment with 15-diopter Fresnel prisms improves visual perception test scores but not ADL function in stroke patients with homonymous hemianopia or unilateral visual neglect.
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