Abstract
Purpose:
To examine whether the intrinsically photosensitive retinal ganglion cells (ipRGCs) are preserved in genetically confirmed autosomal dominat optic atrophy (ADOA).
Methods:
29 patients, aged 18 to 72 years, with either the c.983A>G (n=14) or the c.2708_2711delTTAG mutation (n=15) were examined with monochromatic pupillometry, using isoluminant (300 cd/m2) red (660 nm) or blue (470 nm) light, optical coherence tomography (OCT), automated visual field analysis (VFA), and with determination of best corrected visual acuity (BCVA). Since two different mutations were examined, initially we compared all outcome variables between the two, and finding no statistically significant difference (p> 0.05) between them, we pooled them and compared this sample of 29 patients to an age matched control group of 40 healthy controls
Results:
BCVA was poor (56 letters ETDRS, compared with 91 letters in controls, p<0.0001, t-test) in the ADOA patients, but their post-illuminatory pupil response (PIPR) did not differ significantly from those of an age matched control group (blue light: ADOA/controls = 1.04 , p=0.45; red light: ADOA/controls = 1.06, p=0.49, t-tests) and no statistically significant effect was noted of peripapillary retinal nerve fiber layer thickness, ganglion cell-inner plexiform layer thickness or age.
Conclusions:
The pupillary light reflex (PLR) to blue light of 300 cd/m2 was preserved in both mutations despite severe visual loss and optic nerve atrophy. The study confirms, in a large study of two genetically homogeneous groups, that the intrinsically photosensitive retinal ganglion cells (ipRGCs) are spared in ADOA, and that the decline of their function with age is nonsignificant as compared with that of a healthy control group.