Background: Classic teaching suggests that surgery for intermittent exotropia should be based on distance/near differences. Divergence excess, according to tradition, should be treated with symmetric lateral rectus recessions; simulated divergence excess and basic deviations should be treated with a recess/resect procedure. This teaching, to our knowledge, has not been systematically tested. Objectives: To evaluate the appropriateness of selective surgery based on distance/near differences and to determine if bilateral lateral rectus recessions affect the distance deviation more than the near deviation. Patients and Methods: Patients with basic type intermittent exotropia were randomized to 2 groups, those receiving either unilateral recess/resect procedures or symmetric lateral rectus recessions. Patients with simulated divergence excess intermittent exotropia received symmetric lateral rectus recessions. Outcome was observed 1 year after surgery. Results: Of 19 patients with basic exotropia receiving lateral rectus recessions, 10 patients (52%) had a satisfactory outcome compared with 14 (82%) of the 17 pa
Background: Burian's classification of exotropia based on the difference between the distance deviation and near deviation (distance/near differences)leaves some questions unanswered. Controversy exists concerning whether the divergence excess pattern is caused by an excess of divergence or by excessive accommodative convergence. Much of the literature on this subject has been confusing because investigators did not eliminate tenacious proximal fusion as an artifact in calculating the ratio of accommodative convergence to accommodation (AC/A ratio). Previously, one of us (B.J.K.) proposed a classification system that respected this artifact and subdivided the classification system proposed by Burian.Methods: A total of 202 consecutive patients with an exotropia underwent a series of measurements to determine the respective role of accommodative convergence and tenacious proximal fusion as a cause for their distance/near differences. In addition, the value obtained by a rapid prism adaptation test as a possible substitute for 1 hour of monocular occlusion was studied.Results: In 98 patients, the initial distance deviation exceeded the near deviation. In 10 patients, the distance/ near differences were caused by a high AC/A ratio, which
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.