Short-term effect of prism adaptation treatment on severity of unilateral spatial neglect following right hemispheric stroke: a systematic review and meta-analysis.

Objective: This work aimed to investigate the effects of prism adaptation on unilateral spatial neglect following right hemispheric stroke.

Design: Systematic review and meta-analysis of randomized controlled trials (RCTs).

Patients: Patients with unilateral spatial neglect following right hemispheric stroke.

Methods: RCTs comparing prism adaptation with placebo therapy were systematically searched across 4 databases (PubMed, Web of Science, CINAHL, and Cochrane Library). Screening, data extraction, and quality assessment were performed by 2 independent reviewers.

Results: A total of 7 RCTs, involving 227 participants, satisfied the eligibility criteria. The results showed significant short-term effects of prism adaptation on neglect outcomes (SMD: 0.49 [95% CI: 0.07 to 0.92], p = 0.02) but not on the Catherine Bergego Scale (CBS) (SMD: -0.38 [95% CI: -1.27 to 0.51], p = 0.40). Subgroup analyses revealed that larger prism angles (exceeding 10°) had greater prism adaptation effects on both neglect outcomes and CBS (SMD: 0.71 [95% CI: 0.30 to 1.12], p = 0.0007 and SMD: -0.77 [95% CI: -1.51 to -0.02], p = 0.04, respectively).

Conclusion: This study demonstrated that larger prism angle with greater than 10° was identified as a crucial factor in eliciting prism adaptation effects. These findings support the use of prism adaptation with angles exceeding 10° as a therapeutic approach for unilateral spatial neglect.