Purchase this article with an account.
Dolly Shuo-Teh Chang, Michael V Boland, Karun Arora, David S Friedman; The relationship between quantitative pupillometry and estimated ganglion cell counts in patients with glaucoma. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3303.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To assess the relationship between the pupillary light reflex and estimated retinal ganglion cell (RGC) counts in patients with glaucoma.
We included both eyes of 148 patients with glaucoma in at least one eye (mean age 67±11, 49% female) in a prospective case-control study. Pupil responses were recorded and analyzed using an automated binocular pupillometer at multiple, controlled stimulus intensities while using varied stimulus patterns and colors. The amplitude of pupil constriction was calculated by the percentage change in pupil diameter between constriction onset and peak constriction in response to stimuli. The magnitude of a relative afferent pupillary defect (RAPD) was calculated by the log of the relative ratio of the amplitude between two eyes multiplied by 10. RGC counts were estimated using empirical formulas that combine estimates from both functional (eccentricity and sensitivity measured by standard automated perimetry) and structural (retinal nerve fiber layer thickness - RNFL) tests. For analyses performed at the level of individual eyes, we used multi-level modeling to account for between-eye correlations within individuals.
The average mean deviation of included eyes was -7.3±7.3 dB (range -30.2 to 4.2) and the average RNFL thickness was 66.7±16.1μm (range 30 to 112). Eyes with lower estimated RGC count had smaller response amplitude (p<0.001), longer time to constriction (p=0.002), and slower constriction velocity (p<0.001). RGC count was not associated with dilation velocity (p=0.10) after adjusting for age and gender. For every 0.3 log unit difference in RAPD score, there was an average decrease in estimated RGC counts of 79,299 (p<0.001).
There is a statistically significant association between estimated RGC count and pupillary response to stimuli. Quantitative pupillography may be useful in diagnosis and monitoring of optic neuropathies.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only