Brien Holden Vision Institute.

Brien Holden Vision Institute.

Form-deprivation myopia can be induced in the mouse. This model may be useful to investigate underlying mechanisms of myopia in mammals, because of easier handling and availability of genetically manipulated strains.

No abstract

Aim-To compare the eYcacy of reoperation and botulinum toxin injection in treating infantile esotropes early after unsatisfactory surgical alignment. Methods-55 strabismic children who had been unsuccessfully operated for infantile esotropia were randomised to reoperation (28 patients) or botulinum toxin injection (27 patients). The motor outcomes (percentage of successful motor outcome and percentage change in deviation) were compared at 6 months, 1 year, and 3 years after retreatment, and the sensory outcomes (percentage with fusion ability and stereo perception) at the 3 year follow up visit. Results-The motor and sensory outcomes and the stability of motor results were similar in patients reoperated and treated with botulinum injection. At the 3 year visit 67.8% and 59.2% of children were, respectively, within 8 prism dioptres of orthotropia (p=0.72). The frequency of fusion ability was, respectively, 60.7% and 51.8% (p=0.71), and the frequency of stereo perception (<400 seconds of arc, Randot circles), 57.1% and 48.1% (p=0.70). The botulinum injection was more likely to be eVective when carried out in the 6 months following initial surgery. Conclusions-Botulinum injection is a rapid and less invasive alternative to reoperation in children who have been unsuccessfully treated with surgery to correct infantile esotropia. (Br J Ophthalmol 1999;83:783-787) In a recent study, botulinum toxin injection was found to be as eVective as reoperation in the retreatment of children previously operated to correct an acquired esotropia, particularly in early failures or patients retreated soon after the primary procedure.1 After surgery for infantile esotropia it is also necessary to retreat children in many cases. Often motor success is defined as a deviation equal to or less than 8 or 10 prism dioptres. The motor success rates of 50-65% with the traditional 5 mm maximum for recession of the medial recti 2-5 improved to 84% with recessions measured from the corneoscleral limbus or augmented recessions. [6][7][8][9] It follows that about 20% of patients may need a second procedure. Undercorrections are usually predominant among failures, 2-5 7-9 but other authors have also found overcorrections in a considerable number of results.6 Although the proportion of infantile esotropes who require a secondary procedure is near to that found for acquired esotropes, it is questioned whether the sensory results obtained in the former category may be as good as in the latter. 10-13In this study we compare the eYcacy of the two extant therapeutic options-reoperation and botulinum toxin-after an unsatisfactory result of surgery for infantile esotropia, a clinical setting with presumably less fusional and stereo perception potential than acquired esotropia. MethodsWe included in the study children with infantile esotropia who required a second procedure for alignment in whom the initial surgery was performed between 1990 and 1994. Participants should have been operated for the first time before 24 months of age and retreated ...