The afferent pupillary defect in asymmetric glaucoma
R. H. Brown, J. D. Zilis, M. G. Lynch and G. E. Sanborn
Department of Ophthalmology, University of Texas Health Science Center, Dallas 75235-9057.
The OCTOPUS 2000 perimeter and a central 30 degrees program were used to
study consecutively 27 patients with glaucoma who had either a relative
afferent pupillary defect (APD) or asymmetric optic nerve cupping without
an APD. The mean difference in visual field sensitivity between fellow eyes
was 48.2% (range, 13% to 93%) for the APD group and 5.5% (range, 0% to
9.0%) for the non-APD group. The mean difference in cup-disc ratio was 0.43
(range, 0.2 to 0.6) for the APD group and 0.24 (range, 0.2 to 0.3) for the
non-APD group. The APD depth was quantitated with neutral density filters
and correlated with visual field asymmetry but not with cup-disc ratio
asymmetry. There was no overlap between the APD and non-APD groups in the
amount of visual field asymmetry: Every patient with a sensitivity
difference of 13% or greater had an APD. The presence of an APD indicates
that a threshold of asymmetric optic nerve damage has been exceeded. With
automated perimetry, this threshold can be quantitated and may improve the
assessment of patients with glaucoma.