G343(P) Experience of muscle magnetic resonance imaging in a small neuromuscular service

Abstract

Aim The number of known neuromuscular conditions has increased significantly with recent advances detailing molecular characteristics and this can present a diagnostic challenge. In addition to the clinical presentation and investigations such as muscle biopsy and neurophysiology the magnetic resonance imaging (MRI) pattern of muscle involvement can provide useful information towards achieving a diagnosis. Our aim was to evaluate the use of skeletal muscle MRI as a diagnostic tool in a relatively small neuromuscular service. Methods Children with a suspected neuromuscular disorder but without a specific diagnosis had muscle MRI performed. All children had T1-weighted imaging at two levels (the thigh and lower limb). Some cases also had T2-weighted or short tau inversion recovery (STIR) imaging. The scans were jointly reviewed by a paediatric neurologist and a radiologist with an interest in musculoskeletal imaging. Results Since 2007 13 children have had skeletal muscle MRI in this centre. In 3 patients the pattern of MRI involvement contributed directly to the diagnosis and in 2 cases it helped direct the muscle biopsy. In a further 3 patients a normal MRI helped in a decision to avoid, or at least defer, a muscle biopsy. Details of their clinical presentations and MRI findings are presented. Conclusion Muscle MRI is a useful tool in the diagnostic process of children with suspected neuromuscular disorders. We believe that our experience demonstrates its benefits in a relatively small service.