Relative Afferent Pupillary Defect With Normal Visual Function-Reply

In Reply.  —We thank Drs Sinoff and Rosenberg for their interest in our case report and the opportunity for further clarification of our findings and their significance. Before editorial changes were made, our original manuscript submitted to the Archives included the following statement: "The amplitude of the RAPD in our patient is larger than that reported by Johnson and Bell.¹ This may have resulted from contraction anisocoria.^2-4 If the direct pupillary response is greater than the consensual response because of midbrain disease...,² it would require more neutral density filter to neutralize the afferent defect."In our study, a swinging flashlight test was carried out clinically with our patient requiring a neutral density filter of 1.8 log units to reverse the apparent relative afferent defect. Infrared pupillography, however, was carried out, not by the "swinging flashlight" technique, as Drs Sinoff and Rosenberg not unreasonably presumed, but by stimulating