Strabismus Surgery for Esotropia, Down Syndrome and Developmental Delay; Is an Altered Surgical Dose Required? A Literature Review

Abstract

Background and Purpose: There is a high rate of strabismus, in particular esotropia, in children with Down syndrome or developmental delay, which frequently requires surgical correction. A paper in 1994 advocated that the surgical dose be adjusted due to an altered response in these children. The aim of this literature review is to evaluate the available evidence to establish whether an altered surgical approach is required in either population. Methods: A literature review was conducted using PubMed and Web of Knowledge. Only English language papers were eligible for inclusion. The papers were collated in chronological order for analysis, and their references searched for further relevant papers. Forward citation searches were also undertaken. Results: A 2 × 2 comparison is made between publications on Down syndrome (in isolation) and developmental delay populations (including Down syndrome) with adjusted versus non-adjusted surgery. Published surgical success rates on esotropia from unaltered surgical doses range from 62.0%-85.7% (four papers) in the Down syndrome cohort, with none of the adjusted surgeries having a successful outcome. Surgical success rates from adjusted surgical doses in developmental delay cohort range from 37.5%-86.0% (seven papers), with one unadjusted surgical success rate of 76.0%. The results across the studies are summarised in a table and discussed. Conclusions: An exaggerated surgical effect in individuals with developmental delay has been reported, and this population may benefit from a reduced surgical dose. Published research does not support giving a reduced surgical dose in individuals with Down syndrome, but more research needs to be done to make a definitive conclusion.

Frequency of Strabismus with Down Syndrome

“…superior or inferior and medial or lateral. 7 Agonists and antagonists are the muscles acting at the same time. Opposite muscles of other eye are equally innervated at the same time i.e.…”

Neuro-Ophthalmological Manifestations in Children with Down Syndrome: Current Perspectives

“…The surgical treatment for esotropia in Down syndrome is highly effective, with no need to adjust the surgery dosage recommended for typically developing children. 118,119 The success rate after classical surgical procedures is reported to be between 66 and 90%. 37,[120][121][122] Visual acuity and accommodation tests, suitably adapted for intellectual level, will allow amblyopia to be detected then treated, and therefore improve visual outcomes in children with Down syndrome.…”