Authors: Elise V. Taniguchi1, MD; Izabela Almeida1, MD; Cecília Agapito2, MD; Claudio Zett1, Carolina Gracitelli1, MD, PhD; Letícia Sant’Ana1, MD; Cristiane Kayser2, MD, PhD; Tiago Prata1, MD, PhD; Augusto Paranhos1, MD, PhD

1Department of Ophthalmology, Federal University of Sao Paulo
2Department of Rheumatology, Federal University of Sao Paulo

Purpose: To evaluate ocular and systemic vascular features of open angle glaucoma (OAG) and healthy controls, using optical coherence tomography angiography (OCT-A), nail-fold capillaroscopy, laser Doppler imaging and rheumatology blood tests.

Methods: Twenty-five open angle glaucoma patients, with visual acuity better than 20/60, and no previous glaucoma surgeries in at least one eye were recruited to this study, along with twenty-five age-matched healthy subjects. OCT-A (DRI OCT Triton, Topcon, Japan) was performed in both eyes of all subjects and each set of scans comprised images of the optic nerve head and macula. Nail-fold capillaroscopy (Stereo Microscope SZ40, Olympus, Japan) was performed in all fingers of both hands, except thumbs and the following parameters were evaluated: number of hemorrhages, number of dilated loops and number of tortuous capillaries; Laser Doppler imaging (Moor LDI-VR, Moor Instruments, Axminster, UK) was used to measure fingertip blood flow (FBF) on the non-dominant hand in the following time points: Baseline, 1, 10 and 20 minutes after cold stimulus at 14°C (CS). Measurements are expressed as perfusion unit (PU). Rheumatology blood tests include antinuclear antibody, extractable nuclear antigens, anti-DNA antibodies and Endothelin 1.

Results: 66.7% of OAG patients presented with nail-fold abnormalities versus 16.7% of healthy controls (p=0.04, Chi-Square). There was a significant difference in the FBF mean baseline of OAG patients versus controls (318.7 ± 86.2 vs. 398.2 ± 46.0 PU, respectively, p=0.005, together with a significant decrease in FBF at 10 and 20 minutes after CS in OAG patients in comparison to controls (p=0.008 and p=0.0001, respectively). There was no significant difference in the foveal avascular zone area measurement of OAG (n=10) and controls (n=10) (323.26 ± 97.27 vs. 285.32 ± 64.67 vs, respectively, p=0.37) However, a significant correlation was found between FAZ area and FBF at 20 minutes (R2=0,27, p=0,049).

Conclusions: These preliminary results support systemic vascular abnormalities could be present in OAG patients.