Sparser macula microvasculature in neuromyelitis optica spectrum disorder occurs independently of optic neuritis.

Purpose: To evaluate the macula microvascular perfusion in neuromyelitis optica spectrum disorder (NMOSD) patients and assess the correlation with their clinical features.
Methods: 35 aquaporin-4 seropositive NMOSD patients (38 NMOSD eyes without optic neuritis, NMOSD-NON, and 32 NMOSD eyes with optic neuritis) and 35 healthy controls (HC) were included in our study. Swept-source optical coherence tomography angiography (SS-OCTA) was used to image and segment the macula microvasculature into the inner macula vascular complex (IVC), superficial vascular plexus (SVC), and deep vascular plexus (DVC). An inbuilt software within the OCTA tool was used to measure the microvascular perfusion in these two plexuses.
Results: NMOSD eyes without optic neuritis showed sparser (P < 0.05) IVC and SVC compared with healthy controls; NMOSD eyes with optic neuritis showed significantly sparser (P < 0.001) IVC, SVC, and DVC when compared with healthy controls respectively. NMOSD eyes with optic neuritis showed significantly sparser IVC (P = 0.002), SVC (P = 0.001) and DVC (P = = 0.040) when compared with eyes without optic neuritis.
Conclusions: Microvascular impairment in NMOSD patients occurs independently of ON. Microvascular impairment is associated with reduced visual acuity and frequency of ON.
(Copyright © 2021. Published by Elsevier B.V.)