Anatomical and functional changes in paravascular abnormalities after epiretinal membrane removal

To investigate the anatomical and functional changes in areas containing paravascular abnormalities (PVA) in eyes with epiretinal membrane (ERM) after surgery.

Twenty-eight eyes with concurrent idiopathic ERM and PVA were enrolled in this prospective study. Best-corrected visual acuity (BCVA), central macular thickness (CMT), and areas of PVA in the superficial and deep capillary levels detected on en face optical coherence tomography were measured preoperatively and 1, 3, and 6 months postoperatively. Retinal sensitivity in selected PVA lesions was evaluated by microperimetry preoperatively and 1 and 6 months postoperatively.

The areas of PVA at the superficial capillary level before and 1, 3, and 6 months after surgery measured 1.65 ± 1.27, 0.44 ± 0.62, 0.40 ± 0.64, and 0.38 ± 0.62 mm², respectively, while those at the deep capillary level measured 0.27 ± 0.57, 0.10 ± 0.26, 0.09 ± 0.29, and 0.05 ± 0.15 mm², respectively. The areas of PVA in the superficial and deep capillary levels were significantly smaller postoperatively (all p < 0.001 at the superficial capillary level and p = 0.010 at the deep capillary level). Average retinal sensitivity values in the PVA lesions before and 1 and 6 months after surgery were 11.2 ± 3.5, 12.9 ± 3.2, and 13.2 ± 2.7 dB, respectively; the values at postoperative months 1 and 6 were significantly improved (p = 0.045 and p < 0.001, respectively). BCVA and CMT were significantly improved postoperatively.

PVA not only improves anatomically but also functionally after ERM surgery. Vitrectomy can improve not only central vision but also retinal sensitivity in areas of PVA.