RELATIVE AFFERENT PUPILLARY DEFECTS IN PATIENTS WITH LEBER HEREDITARYOPTIC NEUROPATHY AND UNILATERAL VISUAL-LOSS

PURPOSE: It has been suggested that the pupillary light reaction is re latively preserved in the affected eyes of patients with Leber heredit ary optic neuropathy (LHON), To test the hypothesis that visual-pupill omotor dissociation exists in LHON, we performed a retrospective study to evaluate the magnitude of the relative afferent pupillary defect ( RAPD) in patients who had experienced monocular visual loss. We also c ompared the size of the measured RAPD with the size of the RAPD that w ould be expected on the basis of documented visual field loss. METHODS : We identified a cohort of patients with LHON and monocular visual lo ss, whose pupillary reactions had been quantified using neutral densit y filters. From a review of the case records, we determined whether an RAPD was present, as well as the magnitude of the documented RAPDs, W e also calculated the expected size of the RAPD for each patient, usin g previously established templates that correlated the size of the RAP D with the degree of visual field loss. RESULTS: An RAPD was identifie d in all 10 patients in this study. There was no significant differenc e between the size of the measured and predicted RAPD, nor did the siz e of the RAPD correlate with visual acuity or the time interval betwee n the onset of visual loss and evaluation. CONCLUSION: The results of this study do not support the hypothesis that visual-pupillomotor diss ociation is a common feature of LHON. (Am J Ophthalmol 1998;126:291-29 5, (C) 1998 by Elsevier Science Inc. All rights reserved.).