Trends in macular and optic nerve head vessel density following myopic photorefractive keratectomy

Purpose We aimed to apply Optical Coherence Tomography Angiography (OCTA) to comprehensively assess changes in the optic nerve head (ONH) and macular perfusion before and after the myopic photorefractive keratectomy (PRK). Methods A total of 26 myopic patients eligible for PRK were included based on specific criteria, with meticulous exclusion criteria in place to minimize potential confounders. Participants underwent OCTA assessments of the ONH and macula using the Spectralis OCT (Heidelberg) before, as well as at 1 and 3months after PRK. MATLAB software was utilized for image analysis. Results The average age at the time of surgery was 31.3 ± 5.82years with 26.9% of participants being male. The mean intraocular pressure before the surgery was 15.84 ± 2.46 mmHg. Significant alterations were observed in macular vessel density, emphasizing regional variations in vascular response. Regarding Large vessel density (LVD), there was a significant decrease in Superficial Vascular Complex (SVC) (from 24.21–18.67%, P = 0.011) and deep vascular complex (DVC) (from 26.93% to 21.81, P = 0.003) between before surgery and 3 months later. Similarly, in Capillary Vessel Density (CVD (, significant changes were observed between before surgery and 3 months later in SVC (from 18.22–21.16%, P = 0.004) and DVC (from16.89–21.44%, P = 0.002). In comparison to the macula, vascular densities were more stable overtime in optic nerve head. In both LVD and CVD, only DVC had significant decrease between before surgery and 3 months after (P = 0.008, and 0.038 respectively). Conclusions While PRK appears to maintain the integrity of certain ocular structures, alterations in macular and optic nerve head perfusion post-PRK suggest potential effects on retinal blood supply. Long-term monitoring is crucial to understand the implications of these changes, particularly in the context of conditions such as diabetes.