Purpose:
Correlation of retinal nerve fiber layer (rNFL) thinning measured by optical coherence tomography (OCT) and visual field defects measured by Humphrey Visual Field (HVF) testing has been well documented in cases of glaucomatous optic neuropathy, but less is known about other optic neuropathies. We attempt to show if a relationship exists between OCT and HVF in patients with optic atrophy due to various etiologies.
Methods:
Retrospective chart review from 2002–2005. Subjects included if optic atrophy and reliable 30–2 HVF testing and OCT of the peripapillary rNFL were obtained within 3 months of each other. Subjects were divided into 3 groups based on the etiology of optic atrophy: pseudotumor cerebri (n=6), optic neuritis due to multiple sclerosis (n=10) and miscellaneous (n=18). HVF points were correlated to anatomic quadrants of the optic nerve using methods previously described in the literature by Wirtschafter and Garway–Heath. HVF depression for each quadrant on total deviation plot was designated as mild (–1 to –5db), moderate (–6 to–15db), and severe (>–15db). The average rNFL thickness and percent reduction from a normative database for each quadrant was calculated.
Results:
PERCENT NFL REDUCTION BY OPTIC NERVE QUADRANT
Conclusions:
1. There appears to be a relationship between the severity of visual field defects and rNFL thinning except in the temporal quadrant. 2. The Wirtschafter and Garway–Heath methods of anatomical correlation of optic nerve head and HVF plots are very similar, with biggest differences in temporal quadrant, where the number of visual field points differs most.
3. There was a similiar relationship between HVF defects and rNFL thinning between the optic neuritis/MS group and miscellaneous etiology group, but not in pseudotumor cerebri group. This may indicate that gliosis from chronic severe papilledema can alter OCT values.
Keywords: visual fields • optic disc • neuro-ophthalmology: optic nerve