Topographic correlation of retinal vascularity and electrophysiology in Nepalese high myopes: Insights for early detection and monitoring.

BACKGROUND

mfERG and OCTA parameters have been widely used in myopes to study retinal changes in the myopic retina. However, this study addresses the sensitivity of mfERG and OCTA in tracking myopic axial length changes.

METHODS

Forty high myopes (mean spherical equivalent, MSE ≥ -6.00D) and 40 age- and sex- matched emmetropes (MSE=0.00D) underwent a comprehensive eye examination, including ocular biometry, OCTA for assessment of superficial capillary plexus vessel density (SCP-VD) and deep capillary plexus vessel density (DCP-VD), and mfERG for measuring N1 and P1 amplitude and implicit time. Correlation between mfERG and OCTA parameters was evaluated by comparing Ring 1, Ring 2 and Ring 3 mfERG parameters with foveal, parafoveal (3 mm) and perifoveal (6 mm) OCTA parameters, respectively. Receiver Operating Characteristics (ROC) curve analysis was performed to calculate the sensitivity of mfERG and OCTA parameters in tracking myopic axial length elongation in different retinal loci.

RESULTS

In high myopes, mfERG amplitudes and implicit time exhibited a significant positive and negative correlation, respectively, with OCTA parameters in perifoveal and parafoveal zones. In the foveal region, N1 implicit time (AUC= 0.701), in the perifoveal region, DCP-VD (AUC = 0.710), P1 implicit time (AUC = 0.704) and N1 implicit time (AUC = 0.708) demonstrated good sensitivity whereas, in the parafoveal region, SCP-VD (AUC = 0.693) and N1 implicit time (AUC = 0.680) demonstrated average sensitivity in detecting axial length elongation.

CONCLUSION

We infer that mfERG and OCTA parameters show differential sensitivity in tracking axial length elongation in different retinal loci and could serve as tools for myopia management.