High Correlation between OCTA and OCT Measurements in Patients with Optic Atrophy

Abstract

Purpose : Non-invasive retinal imaging such as optical coherence tomography (OCT) is routinely used in evaluation of patients with vision loss, and optical coherence tomography angiography (OCTA) is a new imaging modality that is beginning to be used clinically. In this study, we measured OCT and OCTA in patients with optic atrophy and age-matched controls and determined whether there is OCT-OCTA correlation.

Methods : We recruited patients with vision loss from a single institution using approved protocol and performed a retrospective, cross-sectional study in 28 patients with optic atrophy (mean age 58 ± 3 yrs, range 17-92 yrs) and 18 age-matched controls (mean age 52 ± 5 yrs, range 19-92 yrs). Inclusion criteria for those with optic atrophy include stable vision loss for >6 months, no other cause of vision loss, and Humphrey visual field mean deviation worse than -5 dB. Patients with optic atrophy included non-arteritic and arteritic anterior ischemic optic neuropathy, optic neuritis, cancer, and others. Control subjects included those with no known history or exam findings of optic nerve or retinal issues. We quantified changes in retinal vasculature using custom-written Matlab programs. Statistical analyses performed included Mann-Whitney test and regression analysis.

Results : Compared with age-matched controls, those with optic atrophy had significantly lower vessel area density at the optic disc (0.3370 ± 0.0087, ctrl: 0.4297±0.0074, P<0.0001) and macula (atrophy:0.3436±0.0071, ctrl:0.3876±0.0086, P=0.0018). Similarly, those with optic atrophy had significantly thinner OCT retinal nerve fiber layer (RNFL) thickness (atrophy:61±1 µm, ctrl:91±1 µm, P<0.0001) and macular ganglion cell complex (atrophy:58±2 µm, ctrl: 80±1 µm, P<0.0001). Regression analysis revealed significant correlation between OCTA disc vessel density and OCT RNFL thickness (R²:0.4913, P<0.0001) and between OCTA macular vessel density and OCT macular ganglion cell complex thickness (R²:0.2152, P=0.0003). There was also significant correlation between OCTA disc and macular vessel densities (R²:0.362, P<0.0001) and RNFL and macular GCC thickness (R²:0.8239, P<0.0001).

Conclusions : In patients with optic atrophy, there was significant thinning of the OCT RNFL and macular ganglion cell complex compared with age-matched controls, and these changes were significantly correlated with a decrease in both optic disc and macular vessel density on OCTA.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.