Interventions for intermittent distance exotropia.

Abstract

The clinical management of intermittent distance exotropia has been discussed frequently in the literature but there is a lack of clarity regarding the indications for intervention, the most effective type and the optimum age at which it should be carried out. The objective of this review is to assess intervention criteria, the effects of various surgical and non-surgical treatments in people with intermittent distance exotropia and to determine the significance of factors such as age with respect to outcome. We searched the Cochrane Central Register of Controlled Trials - CENTRAL (which contains the Cochrane Eyes and Vision Group trials register) on the Cochrane Library (Issue 4 2002), MEDLINE (1966 to November 2002), EMBASE (1980 to November 2002) and LILACS (Latin American and Caribbean Literature on Health Sciences) (1966 to 2002). We manually searched the British Orthoptic Journal, proceedings of the European Strabismological Association (ESA), International Strabismological Association (ISA) and American Academy of Paediatric Ophthalmology and Strabismus meeting (AAPOS). We contacted researchers who are active in the field for information about further published or unpublished studies. There were no language restrictions in the manual or electronic searches. We planned to include randomised controlled trials of any surgical or non-surgical treatment for intermittent distance exotropia. Each reviewer independently assessed study abstracts identified from database and manual searches. Reviewer analysis was then compared and full papers for appropriate studies were obtained. No studies were found that met our selection criteria and therefore none were included for analysis. The available literature consists mainly of retrospective case reviews. These are difficult to compare and analyse due to a large variation in the definition of intermittent distance exotropia, intervention criteria and outcome measures. However there seems to be general agreement that non-surgical treatment is most appropriate in small angle deviations or as a supplement to surgery. Studies were found supporting both early and late surgical intervention so the optimal timing of surgical intervention cannot be concluded. Recent work indicates that bilateral surgery may be the most effective surgical procedure in these cases. There is clearly a need for carefully planned clinical trials to be undertaken to improve the evidence base for the management of this condition.