Comparison of the low frequency fluctuation between AQP4 antibody positive and MOG antibody positive patients with optic neuritis

Abstract

Objective To compare the changes of spontaneous brain activity in myelin oligodendrocyte glycoprotein antibody (MOG-Ab) positive and Aquaporin 4 antibody (AQP4-Ab) positive neuromyelitis optica spectrum disorder (NMOSD) by using resting-state functional magnetic resonance imaging (fMRI). Methods A case control study was designed.A total of 11 NMOSD patients with positive MOG-Ab and 21 NMOSD patients with positive AQP4-Ab were enrolled from October 2006 to May 2017 in PLA General Hospital.Thirty-four healthy controls closely matched in age, sex and education were recruited and underwent resting-state fMRI scans.The amplitude of low-frequency fluctuation (ALFF) was extracted to investigate the spontaneous brain activity.This study was approved by Ethics Committee of PLA General Hospital (S2019-111-01). All subjects enrolled signed informed consent. Results Two patients in the MOG-Ab positive group had seizure history, and no seizure history was observed in AQP4-Ab positive group and healthy control group.Compared with healthy control group, all patients in MOG-Ab positive group and AQP4-Ab positive group had significantly increased ALFF values of prefrontal gyrus.The ALFF values of bilateral anterior central gyrus and bilateral posterior central gyrus in AQP4-Ab positive group were 1.89±0.56 and 2.10±0.69, respectively, which were lower than 3.32±1.15 and 3.61±1.23 in MOG-Ab positive group, the differences were statistically significant (both at P<0.001, AlphaSim correction). Conclusions Resting-state fMRI could provide new evidence of possibly multi-focal disease mechanisms.Hyperactivity in prefrontal cortex, motor cortex and somatosensory cortex might reflect differences in pathological processes between MOG-Ab positive and AQP4-Ab positive NMOSD patients. Key words: Optic neuritis; Resting-state functional magnetic resonance imaging; Amplitude of low frequency fluctuation; Neuromyelitis optica spectrum disorder; Aquaporin 4 antibody; Myelin oligodendrocyte glycoprotein antibody