Afferent Pupillary Defect in Asymmetric Glaucoma

To the Editor.  —In their article on the afferent pupillary defect in asymmetric glaucoma, Brown and coworkers¹ failed to acknowledge two pertinent references. The first report of the presence of an afferent pupillary defect in patients with glaucoma was by Levitan and coworkers² and was a multiphasic screening project in which five cases of asymmetric glaucoma were found among 42708 cases screened. In 1976, Kaback and coworkers³ reported the presence of an afferent pupillary defect in seven patients with asymmetric or unilateral glaucoma with accompanying visual fields. These authors emphasized that "the presence of this sign accompanied by an equivocal visual field change, or in patients with suspicious cupping who give unreliable fields, could decide the diagnosis of glaucoma ('optic nerve damage') in these predisposed individuals."