Patients who have primary open-angle glaucoma might see a greater impact on their perfused capillary density (PCD) than patients with myopia, according to new research developed using optical coherence tomography angiography (OCT-A). The study, published in the April issue of JAMA Ophthalmology, studied 87 people with myopic eyes with glaucoma, 17 patients with myopic eyes without glaucoma, 93 patients with non-myopic eyes with glaucoma and 51 control participants. These subjects were assessed for perfused capillary density (PCD) using OCT-A.1
Previous research shows PCD is associated with glaucomatous damage, which is easily visualized using OCT-A. One study found a mean PCD in glaucomatous eyes of 80.6%—significantly less than the 93.0% found in normal eyes.2 PCD is also known to decrease in pathological myopia, leading the researchers in this study to look for a possible connection between the two disease states using the new imaging modality.3
They found PCD progressively decreased from the control group’s status to the myopia-without-glaucoma group, followed by the glaucoma-without-myopia subjects. The group with both myopia and glaucoma saw the greatest decrease in PCD.1
Despite the interesting results, the study’s cross-sectional design hinders the researchers from determining if the association is a cause of or is only associated with other confounding factors, the authors note.1
1. Suwan Y, Fard MA, Geyman LS, et al. Association of myopia with peripapillary perfused capillary density in patients with glaucoma: an optical coherence tomography angiography study. JAMA Ophthalmol. April 5, 2018. [Epub ahead of print].