The utility of a direct ophthalmoscope in estimating the magnitude of refractive error using a modification of the Brückner test

Objective: To evaluate the utility of a direct ophthalmoscope in detecting the type and magnitude of refractive error using a modified Brückner test. Methods: In a prospective observational study, participants between the ages of 10 to 40 years underwent direct ophthalmoscopy by a single observer, using a modified interpretation of the Brückner test. The results were compared with the adjusted spherical equivalents obtained from retinoscopy (RSE), and subjective correction (SSE). The inter-test agreement, sensitivity, specificity, and predictive values were calculated. Results: A total of 598 eyes were evaluated. In the eyes with a normal glow, the modified Brückner technique had a substantial degree of agreement when compared with techniques of retinoscopy, subjective refractive assessment in predicting the type of refractive error (κ > 0.75). In comparison with the SSE, the test was around 90% sensitive in detecting the presence of hyperopia and myopia of more than 2 diopters, if the upper or lower crescents respectively, were large enough to cross the midline of the pupil. Conclusion: A direct ophthalmoscope is useful in diagnosing the presence and magnitude of spherical refractive errors. Clinical trial registration: Clinical Trials Registry–India (CTRI) No.: CTRI/2018/09/015711; http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=24928&EncHid=&userName=refractive%20errors.