Optical coherence tomography angiography in identifying aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder.

Abstract

Background: Optical coherence tomography angiography (OCTA) has shown promise in assessing microvascular and structural alterations in the retina and optic nerve. This study primarily aimed to evaluate the utility of OCTA in distinguishing aquaporin-4 antibody-positive (AQP4-Ab+) neuromyelitis optica spectrum disorder (NMOSD) patients from healthy controls (HC). Additionally, exploratory analyses were conducted to examine differences between AQP4-Ab + and AQP4-Ab-, all MOG-Ab-negative(double-seronegative) groups in NMOSD patients.

Methods: We retrospectively analyzed clinical data from NMOSD patients admitted to the Neurology Department of our First Hospital from January 2018 to December 2020. Patients were categorized into AQP4-Ab-positive (AQP4-Ab+) and double-seronegative groups, with an age-matched normal control group. OCTA examinations were conducted to compare differences in optic nerve fiber layer thickness, macular central thickness, optic disc, macular blood flow, and clinical characteristics among the three groups.

Results: There were statistically significant gender differences among the three groups, with a higher proportion of females in the AQP4-Ab + group compared to the other two groups (P < 0.05). Structurally, significant differences were observed in all parameters between the AQP4-Ab + group and healthy controls (HC), as well as between the double-seronegative group and HC (all P < 0.05). Direct comparison between AQP4-Ab + and double-seronegative NMOSD patients revealed significant differences in specific OCTA parameters, including optic disc central vessel density (P < 0.001), inner optic disc ring vessel density (P = 0.010), inner optic disc ring superior vessel density (P = 0.008), and outer macular ring nasal vessel density (P = 0.042). However, most other OCTA parameters showed no statistically significant differences between the antibody-positive and antibody-negative subgroups (P > 0.05). The optic disc vessel density demonstrated the highest diagnostic efficiency overall, with the nasal side vessel density of the optic disc achieving an AUC of 0.829.

Conclusion: OCTA exhibits significant clinical utility in diagnosing AQP4-Ab + NMOSD. Differences between AQP4-Ab + and double-seronegative patients were explored and may provide further insight, although further research is required.

Trial registration: Not applicable.