Macular microvaculature evaluation using optical coherence tomography angiography in patients with high myopia

Background: Myopia is one of the common refractive error. Optical Coherence Tomography Angiography (OCTA) is a non-invasive investigation of microvasculature of the retina. Aim: To evaluate the OCTA study of the FAZ area and vascular density (VD) at superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) in myopic patients versus healthy controls and their correlations to axial length (AL), best corrected visual acuity (BCVA) and spherical equivalent (SE). Setting and Design: Prospective cross-sectional comparative study. Methods and material 75 eyes of 54 patients, group A are 50 eyes with high myopia and group B are 25 eyes of age matched healthy controls. OCTA images were obtained, analyzed and compared using SPSS v.12 in both groups. Results: Foveal thickness was significantly increased in the myopic group (259.7±23.9) P=0.025, while the paravfoveal thickness was decreased (305.9±18.5) P < 0.001. Both superficial and deep FAZ area were increased in group A. The foveal VD at SCP was significantly higher in Group A (30.3±5.2) P=0.006. The whole image DCP VD was significantly lower (44.5±5.4) P < 0.001. Regarding CC, there was a significant difference in both foveal and parafoveal VD (66.1±4.9) (66.5±4.6) P=0.006 and 0.017, respectively, with both being higher in group A. The study also showed the importance of the CD at DCP and CC being negatively correlated with LogMAR BCVA and positively with the SE, while foveal thickness was positively correlated with the AL. Conclusion: OCTA is a valid and fast technique that could give insights about microvascular changes in myopia.