Ten mistakes to avoid while testing for RAPD
Introduction: A relative afferent pupillary defect (RAPD) is an important sign that detects a lesion in the afferent pathway of light reflex. It is seen in unilateral or asymmetric bilateral lesions of the retina and optic nerve upto but not involving the chiasm. It has been noted though, even in lesions of optic tract and pretectal afferent fibres of dorsal mid brain. Although the test requires both eyes, it is essential to note that it requires only one working pupil. Swinging flashlight test of Levitan: Before performing the test, one must examine the pupil for shape, size of the pupils, anisocoria if any and reaction to light. It is important to note all these since anisocoria and small sized pupils may make it difficult to detect relative afferent pupillary defect. After completing this basic examination, one must proceed to perform the swinging flash light test, keeping in mind the following ten avoidable mistakes: 1. The ideal light: The test must be performed with a halogen tra

