P123 MRI based criteria to differentiate dysferlinopathies from other genetic muscle diseases

• Published in: Neuromuscular disorders : NMD 2023-10, Vol.33, p.S78-S78
• Main Authors: Diaz, C Bolaño, Verdu-Diaz, J., Gonzalez-Chamorro, A., Straub, V., Manera, J Diaz
• Format: Article
• Language: English
• ISSN: 0960-8966; 1873-2364
• DOI: 10.1016/j.nmd.2023.07.058

Muscle MRI is a useful tool for the diagnosis of neuromuscular diseases as it identifies selective patterns of pathology that are characteristic of a specific diagnosis. In the case of dysferlinopathy (DYSF), we have described the muscle MRI features of 182 patients included in the Clinical Outcome Study for Dysferlinopathies (COS1). Using this data, we were able to identify eight characteristic MRI features labelled “pattern rules” based on the semi-quantitative Mercuri score that were present in nearly 90% of patients. Our aim was to apply this set of rules to patients diagnosed with other genetic muscle diseases (GMD) to determine whether they were a useful diagnostic tool and create a decision tree making algorithm. We used MRI data from 182 patients with DYSF from the COS1 study and 1000 MRI scans of patients with other GMD (ANO5 68, CAPN3 82, DUX4 269, DYS 46, LMNA 80, PABPN1 168, GAA 98, SCGC 76, FKRP 39, VCP 74). We calculated sensitivity (S), specificity (E), positive and negative predictive values (PPV/NPV), accuracy (Ac) and diagnostic odds ratio for each rule (significant p value