Macular and Optic Nerve Head Vessel Density and Progressive Retinal Nerve Fiber Layer Loss in Glaucoma

Abstract

Purpose : To prospectively investigate the relationship between macula and peripapillary vessel density and progressive retinal nerve fiber layer (RNFL) loss in patients with mild to moderate primary open angle glaucoma

Methods : In this prospective observational study, 132 eyes of 83 patients with glaucoma included followed for at least 2 years (mean±SD: 27.3±3.36 months).Measurements of macula whole image vessel density (m-WIVD) and optic nerve head whole image vessel density (onh-WIVD) were acquired at baseline using optical coherence tomography angiography (OCT-A). RNFL measurements were obtained semiannually using spectral-domain optical coherence tomography (SDOCT). Random-effects models were used to investigate the relationship between baseline vessel density parameters and rates of RNFL loss after adjusting for the following confounding factors: baseline visual field mean deviation (MD) central corneal thickness (CCT), and average intraocular pressure (IOP) during follow-up. Main outcome measures were effects of m-WIVD and onh-WIVD on rates of RNFL loss over time.

Results : Average baseline m-WIVD and onh-WIVD were 50.0±3.7% and 58.2±2.4%, respectively. Average baseline RNFL thickness was 79.5 ±14.8 µm which declined with a mean (95% CI) slope of -1.07 µm/year (-1.28, -0.85). In the univariable model, including only a predictive factor and time and their interaction, each 1 % lower m-WIVD and onh-WIVD was associated with a 0.11 µm/year (p<0.001) and 0.06 µm/year (p=0.031) faster rate of RNFL decline, respectively. A similar relationship between low m-WIVD (p=0.008) and onh-WIVD (p=0.046) and faster rates of RNFL loss was found using a multivariable model accounting for age, MD, average IOP and CCT.

Conclusions : Lower baseline macula and optic nerve head vessel density is associated with a faster rate of RNFL progression in mild to moderate glaucoma. Assessment of optic nerve head and macula vessel density may add significant information to the evaluation of the risk of glaucoma progression and prediction of rates of disease worsening.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.