P 44. Structural and functional brain alterations in patients with myasthenia gravis

Introduction. Myasthenia gravis (MG) is an autoimmune disease affecting the peripheral nervous system and causes skeletal muscle weakness. Additionally, systemic inflammation, cognitive deficits and autonomic dysfunction have been described (Gilhus et al., 2019). Here, we investigate structural and functional brain changes in MG patients. Materials & Methods. Eleven MG patients (age: 70.64 ± 9.27; 11 male) were compared to age-, sex- and education-matched healthy controls (age: 70.18 ± 8.98). All patients received cholinesterase inhibitors. Structural brain changes were determined with voxel-based morphometry (VBM) using high-resolution T1-weighted MPRAGE sequences. Functional brain changes were accesed wih a neuropsychological test battery that probed cognitive deficits (MMST), attention, memory and executive functions. Results. MG patients showed significant grey matter volume reductions in the cingulate gyrus, in the inferior parietal lobe and in the fusiform gyrus. Furthermore, MG patients showed significant lower results in working memory (Spatial Span, p = .034, |d| = 1.466) and verbal episodic memory (VLMT, p = .003, |d| = 1.463). Discussion. Our results indicate that MG is associated with structural and functional brain alterations. Especially the grey matter volume changes in the cingulate gyrus and the inferior parietal lobe could be associated with cognitive deficits in memory and executive functions. Future research is needed to replicate this finding in a larger sample size and to investigate structural and functional brain changes in a longitudinal study. Reference Gilhus, Nils Erik; Tzartos, Socrates; Evoli, Amelia; Palace, Jacqueline; Burns, Ted M.; Verschuuren, Jan J. G. M. (2019): Myasthenia gravis. In: Nature reviews. Disease primers 5 (1), S. 30. DOI: 10.1038/s41572-019-0079-y.