Rapid pupil-based assessment of glaucomatous damage.
OBJECTIVE
To investigate the ability of a technique employing pupillometry and functionally-shaped stimuli to assess loss of visual function due to glaucomatous optic neuropathy.


METHODS
Pairs of large stimuli, mirror images about the horizontal meridian, were displayed alternately in the upper and lower visual field. Pupil diameter was recorded and analyzed in terms of the "contrast balance" (relative sensitivity to the upper and lower stimuli), and the pupil constriction amplitude to upper and lower stimuli separately. A group of 40 patients with glaucoma was tested twice in a first session, and twice more in a second session, 1 to 3 weeks later. A group of 40 normal subjects was tested with the same protocol.


RESULTS
Results for the normal subjects indicated functional symmetry in upper/lower retina, on average. Contrast balance results for the patients with glaucoma differed from normal: half the normal subjects had contrast balance within 0.06 log unit of equality and 80% had contrast balance within 0.1 log unit. Half the patients had contrast balances more than 0.1 log unit from equality. Patient contrast balances were moderately correlated with predictions from perimetric data (r = 0.37, p < 0.00001). Contrast balances correctly classified visual field damage in 28 patients (70%), and response amplitudes correctly classified 24 patients (60%). When contrast balance and response amplitude were combined, receiver operating characteristic area for discriminating glaucoma from normal was 0.83.


CONCLUSIONS
Pupillary evaluation of retinal asymmetry provides a rapid method for detecting and classifying visual field defects. In this patient population, classification agreed with perimetry in 70% of eyes.
Chen
Yanjun
Y
Department of Biological Sciences, SUNY State College of Optometry, New York, New York, USA.
Wyatt
Harry J
HJ
Swanson
William H
WH
Dul
Mitchell W
MW
D015350:Contrast Sensitivity / Q000502:physiology; D007839:Functional Laterality; D005901:Glaucoma / Q000473:pathology*; D006801:Humans; D009900:Optic Nerve / Q000473:pathology*; D011680:Pupil / Q000502:physiology*; D011681:Pupil Disorders / Q000473:pathology*; D012160:Retina / Q000473:pathology / Q000502:physiology / Q000503:physiopathology; D014794:Visual Fields