[Prism adaptation test before strabismus surgery : Results of a survey and literature review]. / Prismenadaptationstest vor Schieloperationen : Ergebnisse einer Umfrage und Literaturreview.

ABSTRACT

BACKGROUND: Variable preoperative deviations and compensatory mechanisms may cause wrong dosage of strabismus surgery and result in over- or undercorrection. A long-lasting prism adaptation test (PAT) before surgery is supposed to reduce those difficulties and to improve the postoperative results. To date, the use of prism adaptation before surgery has not been systematically examined. METHODS: A total of 15 strabismologists and 28 orthoptists in Austria were interviewed about their approach to prism adaptation in 9 types of strabismus. They were also asked about the basis of their decision for a certain treatment regime. RESULTS: Of those interviewed, 28% performed preoperative prism adaptation for weeks to years. Of those, 7% based their decision on evidence from the literature, 54% decide on personal experience, 15% due to guidelines of their institution, and 23% follow the teaching of their medical school. DISCUSSION: Reports in the literature reveal inconsistent results on PAT. In published studies, PAT was rarely performed longer than 4 weeks and only shows significant improvements on outcome in particular pathologies as acquired esotropia. Long-term PAT appears questionable as to date there is no evidence for a better postoperative outcome. Before setting up guidelines, further controlled, prospective studies on PAT must be conducted.