Distance Stereoacuity in Children with Intermittent Exotropia Using B-VAT II Video Acuity Tester

ABSTRACT

The purpose of this study is to determine if distance stereoacuity could be used as an objective means of assessing control in intermittent exotropia. We evaluated distance stereoacuity in 37 patients with intermittent exotropia showing orthophoria postopratively using the Mentor B-VAT II Videoacuity tester. All patients had fusion at near but 14 of 31 patients(38%) had fusion at distance preoperatively. The mean preoperative distance stereoacuities were 216 seconds with binocular vision circle(BVC) and 351 seconds with binocular vision random dot E(BVRDE) ( p=0.0002). The postoperative improvement was statistically significant with BVC(p=0.001), not statistically significant with BVRDE(p=0.7). On our results it seems to be easier to know BVC than BVRDE in children. It suggests that the BVC is a useful test for assessing control in intermittent exotropia.