Accuracy of Pupil Assessment for the Detection of Glaucoma

Abstract

Objective To assess the accuracy of using pupillary light reflex (PLR) in detecting glaucoma. Clinical Relevance Glaucoma is a specific disease of the optic nerve and is often more severe in 1 eye. When large enough, this asymmetry in disease severity can cause a relative afferent pupillary defect (RAPD). Better detection of RAPDs may be one way to identify persons with glaucoma. Methods We searched Medline and Embase through June 2012 and searched bibliographies for relevant studies for additional references. Two authors independently reviewed all articles and selected studies that assessed PLRs in patients with glaucoma. We analyzed data using mixed-effect bivariate summary receiver operating characteristic meta-analysis models. Results A total of 30 studies were included in this review. An RAPD was observed in 9% to 82% of patients with glaucoma. Eleven studies with a total of 7271 participants were included in the analysis, and the pooled estimate corresponded to a sensitivity of 0.63 (95% confidence interval [CI], 0.43–0.80) and a specificity of 0.93 (95% CI, 0.85–0.97). After excluding 2 studies that used the swinging flashlight test, the sensitivity increased to 0.74 (95% CI, 0.59–0.85) with a specificity of 0.85 (95% CI, 0.77–0.90). Study designs and different pupil measurement techniques explained part of the heterogeneity between studies. Conclusions Patients with glaucoma frequently have an abnormal PLR and comparing the responses between the 2 eyes can in part distinguish between those with glaucoma and those without the disease. Newer instruments and analytic approaches to assess pupil function may improve the performance of pupil screening.

Detecting Glaucoma Using Automated Pupillography

“…For example, a recent systematic review found that relative afferent pupillary defect (RAPD) can be detected in one third to two thirds of glaucomatous patients using the swinging flashlight test. 7-9 An RAPD is an important marker of asymmetric impairment of the afferent visual system and, in a subject with glaucoma, is likely to indicate significant damage to the optic nerve. 10,11 Moreover, the magnitude of the pupillary response defect has been shown to correlate with the severity of disease.…”

Clinical Characteristics and Current Treatment of Glaucoma

“…Thus unilateral or markedly asymmetric glaucoma does not alter pupil size but it will produce an afferent pupillary defect on a swinging flashlight test. (Schiefer et al 2012;Chang et al 2013). When light is placed in front of the healthier eye, both pupils constrict, but when the light swings over to the eye with more optic nerve disease, afferent conduction is slowed and the pupil exhibits a paradoxical dilatation.…”

Detection of asymmetric glaucomatous damage using automated pupillography, the swinging flashlight method and the magnified-assisted swinging flashlight method

“…However, the proportion of patients with asymmetric glaucoma was similar to other reports. 14 Second, we had a heterogeneous sample of patients that included subjects with diagnosis of glaucoma, glaucoma suspect, and ocular hypertension. Patients with glaucoma suspect and ocular hypertension status may have less asymmetric damage than those with more advanced disease, and the extent of this asymmetry may vary according to the clinical index used.…”

“…13 A systematic metaanalysis has suggested that older generations of automated pupillography, including pupil cycle time, infrared video pupillography, and pupil perimetry have higher sensitivity and specificity than the SFM in detecting glaucoma. 14 In this study, we directly compared the ability of the SFM, MA-SFM and the RAPDx pupillograph to detect asymmetric glaucomatous damage, as defined by standard clinical measures of optic nerve structure and function.…”