97th DOG Annual Meeting 1999
AUTOMATED SWINGING FLASHLIGHT TEST
T. Peters, H. Lüdtke, B. Wilhelm, R. Schmid, H. Wilhelm
Introduction: The swinging flashlight test is a valuable method to diagnose an assymmetric optic neuropathy objectively. However, the test depends from the examiners experience and skill, and there are many pitfalls that may lead to inadequate results.
Methods: We added an illumination device consisting of LED arrays to a binocular recording pupillograph. Be means of this set-up the swinging flashlight test was carried out in 102 normal subjects and 31 patients with optic neuropathies and compared to clinical results.
Results: In normals, a relative afferent pupillary defect of more than 0.3 log units was encountered only in 2 %. 95% were below 0.2 log units. There was a good correlation between clinical testing and pupillography.
Discussion: A pupillographic swinging flashlight test with computerized evaluation is no longer dependent from the examiner and may avoid typical mistakes (e.g. differences in illumination of both eyes). Measuring an RAPD is more precise than clinically. Because of binocular recording and evaluation anisocoria or unilaterally disturbed light reaction do not interfere with the test. An automated swinging flashlight test may serve as a screening method, as a supplement to clinical examination and as an objective method in studies and assessments.
University Eye Hospital, Dept. of Pathophysiology of Vision and Neuro-ophthalmology, D-72076 Tübingen