Optical coherence tomography angiography (OCTA) has been widely used in assessing the retinal and choroidal microvasculature in glaucoma patients. Previous studies demonstrated that there are ethnic differences in macular and peripapillary CD of healthy subjects. Compared to white subjects, black subjects were found to lower macular and peripapillary CD.1-4 However, it is not known if such differences exist in the glaucomatous eyes, and how ethnic differences may affect the diagnostic performance of capillary density in detecting glaucoma patients.
Moghimiet al. evaluated the ethnic differences in the peripapillary CD in the patients with primary open-angle glaucoma (POAG). Results showed that after adjusting for age, disc area, and other confounders, significantly lower peripapillary CD was found in white subjects compared with black subjects in both mild (42.2% vs 46.5%) and moderate to advanced (34.7% vs 38.5%) glaucoma. The adjusted AUROC for discriminating between healthy and glaucomatous eyes for peripapillary CD was higher for white (0.95) compared with black (0.68) patients (P < 0.001).
This is an important study in OCTA imaging of glaucoma, since it is the first to report ethnic differences in glaucomatous eyes and confirmed that we should consider ethnic information when evaluating capillary density of glaucoma patients
This is an important study in OCTA imaging of glaucoma, since it is the first to report the ethnic differences in glaucomatous eyes and confirmed that we should consider ethnic information when evaluating capillary density of glaucoma patients. It should be noted that although white healthy subjects have higher peripapillary CD than black healthy subjects, white patients had lower peripapillary CD than black patients. Such results lead to another question: are there ethnic differences in CD reduction rate? A longitudinal study is needed to provide the answer. As shown in the study, ethnical differences also affect the diagnostic performance of CD in detecting glaucoma. This suggests that upon establishment of a normative OCTA CD database, we will need to consider a number of confounding factors, including age, gender, ethnicity, axial length, to improve the discriminatory power of CD in detecting glaucoma.