High myopia modifies OCT measurements

Optical coherence tomography (OCT) measurements are altered in patients with high myopia, a recent study has found.

The study included 92 high myopia patients (mean age, 35.19±14.29 years; 56 females) who contributed 92 eyes for analysis. OCT was performed to measure the thickness of the retinal nerve fibre layer (RNFL) and of the superior and inferior ganglion cell complex (GCC). A parallel group of 70 eyes from 70 controls (mean age, 36.22±11.42 years; 42 females) was also included.

Compared to controls, patients with high myopia had significantly thinner superior and inferior GCC measurements (p<0.001). RNFL thickness at the superior, inferior, and nasal regions, as well as scores in the Early Treatment Diabetic Retinopathy Study (ETDRS) tool, were likewise significantly different between groups (p<0.001). Central macular thickness did not differ between groups.

Moreover, the superficial (SVD; p=0.005) and deep (DVD; p<0.001) vascular densities were significantly reduced in patients with high myopia.

Researchers then found that both SVD and DVD were negatively associated with axial length (AL). In contrast, GCC, RNFL, and best-corrected visual acuity were all significant and positive correlates.

Multivariate regression analysis additionally showed that in high myopia patients, high SVD was independently associated with shorter AL and greater mean RNFL thickness. DVD, on the other hand, correlated with better visual acuity and shorter AL.

“Vascular alterations may be one of the main pathophysiological mechanisms in high myopia, and alternative treatments and preventive measures targeting these vascular alterations may be the subject of future studies,” researchers said.