A pilot randomized controlled trial comparing effectiveness of prism glasses, visual search training and standard care in hemianopia

Rowe, FJ ORCID: 0000-0001-9210-9131, Conroy, EJ ORCID: 0000-0003-4858-727X, Bedson, E, Cwiklinski, E, Drummond, A, García-Fiñana, M ORCID: 0000-0003-4939-0575, Howard, C, Pollock, A, Shipman, T, Dodridge, C
et al (show 5 more authors) (2017) A pilot randomized controlled trial comparing effectiveness of prism glasses, visual search training and standard care in hemianopia. Acta Neurologica Scandinavica, 136 (4). pp. 310-321.

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Objective: Pilot trial to compare prism therapy and visual search training, for homonymous hemianopia, to standard care (information only). Methods: Prospective, multicentre, parallel, single-blind, three-arm RCT across fifteen UK acute stroke units. Participants: Stroke survivors with homonymous hemianopia. Interventions: Arm a (Fresnel prisms) for minimum 2 hours, 5 days per week over 6 weeks. Arm b (visual search training) for minimum 30 minutes, 5 days per week over 6 weeks. Arm c (standard care—information only). Inclusion criteria: Adult stroke survivors (>18 years), stable hemianopia, visual acuity better than 0.5 logMAR, refractive error within ±5 dioptres, ability to read/understand English and provide consent. Outcomes: Primary outcomes were change in visual field area from baseline to 26 weeks and calculation of sample size for a definitive trial. Secondary measures included Rivermead Mobility Index, Visual Function Questionnaire 25/10, Nottingham Extended Activities of Daily Living, Euro Qual, Short Form-12 questionnaires and Radner reading ability. Measures were post-randomization at baseline and 6, 12 and 26 weeks. Randomization: Randomization block lists stratified by site and partial/complete hemianopia. Blinding: Allocations disclosed to patients. Primary outcome assessor blind to treatment allocation. Results: Eighty-seven patients were recruited: 27—Fresnel prisms, 30—visual search training and 30—standard care; 69% male; mean age 69 years (SD 12). At 26 weeks, full results for 24, 24 and 22 patients, respectively, were compared to baseline. Sample size calculation for a definitive trial determined as 269 participants per arm for a 200 degree2 visual field area change at 90% power. Non-significant relative change in area of visual field was 5%, 8% and 3.5%, respectively, for the three groups. Visual Function Questionnaire responses improved significantly from baseline to 26 weeks with visual search training (60 [SD 19] to 68.4 [SD 20]) compared to Fresnel prisms (68.5 [SD 16.4] to 68.2 [18.4]: 7% difference) and standard care (63.7 [SD 19.4] to 59.8 [SD 22.7]: 10% difference), P=.05. Related adverse events were common with Fresnel prisms (69.2%; typically headaches). Conclusions: No significant change occurred for area of visual field area across arms over follow-up. Visual search training had significant improvement in vision-related quality of life. Prism therapy produced adverse events in 69%. Visual search training results warrant further investigation.

Item Type: Article
Uncontrolled Keywords: homonymous hemianopia, pilot trial, prism therapy, randomized controlled trial, standard care, stroke, visual search training
Depositing User: Symplectic Admin
Date Deposited: 03 Jan 2017 14:02
Last Modified: 19 Jan 2023 07:24
DOI: 10.1111/ane.12725
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3005014