A Novel Use of Retinoscopy for the Evaluation of Binocular Balance of Spherical Refractive Errors

Abstract

Purpose Binocular balancing is an important component of refractive correction to avoid asthenopic complaints. Polaroid filters are commonly used for binocular balancing; they rely on subjective examination and cannot represent daily visual activities. We describe a new examination approach to evaluate binocular balance with retinoscopy, which is an objective examination method and does not require strict patient cooperation. Methods Healthy young individuals with refractive errors (under the age of 40) were included in this study. Each patient was examined by three different ophthalmologists in the same room at 20-min intervals. The first ophthalmologist performed refractive examination separately for each eye, the second physician used binocular balance tests with polaroid glasses, and the third physician practiced binocular balance test with retinoscopy. After completion of clinical examinations, autorefractometry was repeated with cycloplegia. The difference between the spherical equivalents (SE) of the eyes was calculated for each method and compared with the SE difference obtained by cycloplegic autorefractometry. The SPSS 21.0 software was used for the statistical tests. Results The study included 30 patients (16 males, 14 females) and the mean age of the patients was 21 +/- 8.5 years (range 10-37 years). There was no significant difference between the four groups for the interocular difference of SE (Greenhouse-Geisser F = 1.390, p = 0.257). The highest correlation was found between the retinoscopic binocular balance technique and cycloplegic autorefractometry (r = 0.878, p < 0.001). In addition, the intraclass correlation coefficient and the 95% limits of agreement supported strong agreement. Conclusion Currently used binocular examination tests are subjective and some patients give inconsistent answers impairing the reliability of the outcome. These tests cannot be performed on patients with limited ability to cooperate. This study demonstrates that the use of retinoscopy in the evaluation of binocular balance delivers reliable results and is a low-cost, practical approach to address the above-mentioned problems.