Author: El Ouafi Bouazzaoui (Tunisia)
Co-authors: Rahma Saidane, Racem Choura, Asma Khallouli, Slim Selmi, Afef Maalej, Riadh Rannen
To evaluate peripapillary region perfusion changes during different stages of diabetic retinopathy (DR) using Optical coherence tomography angiography (OCTA).
Department of Ophthalmology of the Military Hospital of Tunis, Tunisia.
Thirty-six eyes from 36 diabetic patients and 36 age-matched healthy controls were included in the study. After a complete medical examination, Spectral Domain OCT and OCT-A exams were performed using Optovue RTVue XR Avanti, AngioVue. The scan area used was 4.5 × 4.5 mm centered on the optic nerve head for measurement of Radial Peripapillary Capillaries (RPC) vessel densities including: whole image (wi), inside disc (id) and peripapillary (pp). Peripapillary Retinal Nerve Fiber Layer (RNFL) thickness was also evaluated in all subjects.
The study population was divided into three groups: Group 1 of 13 eyes without DR, Group 2 of 11 eyes with minimal to moderate non-proliferative DR, Group 3 of 12 eyes with severe non-proliferative DR and proliferative DR and 36 age-matched healthy subjects (control group). The mean age was 51.88 ± 7.03 in control group, 48.78 ± 11.79 in group 1, 50.79 ± 9.02 in group 2, 52.00 ± 9.33 in group 3. The sex ratio was 1.15 in each group. A statistically significant decrease in all peripapillary vascular densities with increasing of DR Severity was noted (From group 1 to group 3) (P <0.001). No significant difference in RNFL thickness was found between the 4 groups (p=0.34). There was a significant negative correlation between DR severity and peripapillary vascular densities (r=-0.54, p <0.001). However, no statistically significant association was found with RNFL thickness (r=0.008, p = 0.4). There was a significantly positive correlation between RPC vascular density and RNFL thickness only in group 2 (r = 0.72, P <0.001) (Spearman rank correlation analysis).
OCT-A is a non-invasive imaging modality that may be useful to evaluate peripapillary vascular network damages due to DR. Correlation between DR and peripapillary vascular alterations can be potentially of great help monitoring DR progression.
The authors declare no conflict of interest.