Optical Coherence Tomography Angiography Findings in Primary Progressive Multiple Sclerosis Patients Receiving Ocrelizumab Treatment

<b>Objectives</b>: The aim of this study was to evaluate macular vessel area densities (superficial and deep) and foveal avascular zone (FAZ) measurements using OCT-A in the eyes of primary progressive multiple sclerosis (PPMS) patients receiving Ocrelizumab treatment with or without optic nerve involvement. <b>Methods</b>: The medical records of PPMS patients who received Ocrelizumab treatment at least once were reviewed. Retinal nerve fiber layer (RNFL) thickness measurements and OCT-A analysis were conducted on the PPMS patients and on age-matched healthy individuals. The patient group was divided into two subgroups: eyes with optic neuritis (PPMS+ON) and eyes without ON (PPMS-ON). Central and mean superficial vessel area (SVA) and deep vessel area (DVA) densities, as well as foveal avascular zone (FAZ) measurements, were analyzed. All parameters were statistically compared between groups and subgroups. <b>Results</b>: A total of 38 PPMS patients receiving Ocrelizumab treatment and 31 healthy individuals were included in this study. Statistically significant differences were observed between the groups in terms of best corrected visual acuity (BCVA), RNFL thickness, and the superficial vessel area densities for all parts except for the central part. In terms of deep vessel area densities, differences were found in the central and inferior parts. The mean FAZ area also showed a statistically significant difference between groups. Mean RNFL thickness differed significantly between the subgroups. Mean nasal, temporal, inferior part, and total superficial vessel area densities were statistically different between the subgroups. The central and inferior parts of the deep vessel area densities showed statistically significant differences. The mean FAZ area was also statistically different between the subgroups. <b>Conclusions</b>: The findings suggest that macular superficial and deep vascular densities are affected in PPMS patients receiving the same therapy modality and that previous optic neuritis may influence the results.