Spectral domain optical coherence tomography (SD-OCT) and characteristics associated with glaucoma in community living older adults

Abstract

Purpose: Use of herald areas of the SD-OCT has been suggested for earlier diagnosis of early progression of open angle glaucoma and for screening of people at risk for visual field loss. We sought to examine whether characteristics of nerve fiber layer (NFL) thickness indicate important attributes of the optic disc and visual function characteristics as measured by frequency doubling technology (FDT) perimetry as potential markers of glaucomatous damage in a community of older adults.

Methods: Participants aged 43-86 years at baseline (n=4926) in the Beaver Dam Eye Study were examined up to 5 times approximately every 5 years between 1988-1990 and 2008-2010. At the 2008-2010 examination, SD-OCT scans of the NFL of 1503 participants were obtained and automatically analyzed using the Iowa Reference Algorithms (https://www.iibi.uiowa.edu/content/iowa-reference-algorithms-human-and-murine-oct-retinal-layer-analysis-and-display). Visual field function was assessed via FDT perimetry using the Humphrey Matrix (full-N 30-F). The optic cup and disc of each eye were measured on stereoscopic fundus photographs of Early Treatment Diabetic Retinopathy Study field 1. Intraocular pressures were measured with a Goldmann applanation tonometer after topical anesthesia. Visual fields were manually graded for the presence of specific patterns.

Results: Older age (P=.031) and female sex adjusted for age (P<.001) were associated with thinner NFL. Thicker NFL was found in the superior/superior temporal and inferior/inferior temporal region of both eyes and relative thinning in these areas was associated with increasing age, grader diagnosis of glaucomatous pattern on FDT, and lower pattern standard deviation. There was little effect of intraocular pressure on these patterns.

Conclusions: In a group of community living elders, measures of the NFL from SD-OCT were associated with characteristics of glaucomatous damage. These characteristics may herald future loss of visual field. Further research into the prospective importance of the changes may yield findings that can be incorporated into public health programs for early diagnosis of incipient glaucoma.