Accommodative ability in exotropia: predictive value of surgical success.

PURPOSE: To evaluate the state and symmetry of accommodative response in the two eyes of patients with basic intermittent exotropia and to determine whether accommodative response is a predicting factor to the outcome of unilateral recession-resection procedures or symmetric lateral rectus recessions. METHODS: Dynamic retinoscopy was performed preoperatively on 47 patients with basic intermittent exotropia with the capacity for fusion who were undergoing a first operation for intermittent exotropia. To obtain a clinical measurement of the degree of binocular accommodative response, the monocular estimate method was used. Patients were divided into two groups: those with an "equal effective accommodative response" and those with an "unequal accommodative response" between the two eyes. Both groups received either unilateral recession-resection procedures or symmetric lateral rectus recessions. RESULTS: Thirty-two of 47 patients (68%) showed a persistent interocular difference in accommodative amplitude (asymmetric accommodation) of at least 0.75 D. Among these 32 patients with an "unequal effective accommodation," 5 of 14 patients (35.7%) receiving lateral rectus recessions had a satisfactory outcome compared with 13 of the 18 patients (72%) receiving recess/resect procedures (p = 0.039). Of the 15 patients with an "equal effective accommodation," 7 of 8 (87%) receiving recession-resection procedures had a satisfactory outcome compared with 5 of 7 patients (71%) who had lateral rectus recessions (p = 0.57). CONCLUSIONS: Data suggest that patients with an asymmetric accommodative response benefit more from recession-resection procedures. A decrease in accommodative response of the nondominant eye could be a predicting factor on the outcome of exotropia surgery.

Against-the-rule (ATR) astigmatism as a predicting factor for the outcome of amblyopia treatment.

PURPOSE: To evaluate whether with-the-rule (WTR) or against-the-rule (ATR) astigmatism influences the treatment outcome of anisometropic amblyopia. DESIGN: A cohort study. METHODS: Retrospective study of patients with unilateral amblyopia due to anisometropia without strabismus. Ninety-eight patients with simple, compound, mixed, oblique myopic, and hyperopic astigmatism were divided into seven groups based on the type of astigmatism. The groups were reviewed as to the amount of anisometropia, duration of occlusion, and best-corrected visual acuity (BCVA) before and after treatment. RESULTS: There was statistically significant longer duration of occlusion and less lines gain of BCVA among patients with hyperopic ATR astigmatism compared with patients with hyperopic WTR astigmatism (P =.0143 and P =.0000, respectively) and myopic ATR patients compared with myopic WTR patients (P =.0392 and P =.0192, respectively). For the same parameters, group differences were also statistically significant when all hyperopic or myopic simple/compound/mixed ATR patients were compared with all hyperopic or myopic simple/compound/mixed WTR patients (P =.0015 and P =.0000, respectively). CONCLUSION: The outcome of amblyopia treatment seems to be less favorable in patients with either hyperopic or myopic ATR astigmatism. Near vision impairment may be more amblyogenic than distance vision impairment during visual development.