115P MRI of whole-body muscles and tongue of patients with Spinal Muscular Atrophy

Abstract

Patients with spinal muscular atrophy (SMA) have an autosomal recessive motor neuron disorder that causes their muscles to degenerate. The muscle affection is visible on MRI as progressive muscle atrophy and increased intramuscular fat content. Multiple studies have shown increased intramuscular fat fraction in sections of the body. The bulbar function can also be affected but is not well documented with MRI or functional tests. This study is the first to describe the intramuscular fat fraction of the whole body from the tongue, axial muscles, and arm muscles to muscles of the thigh and calf and to correlate MRI findings of the tongue to bulbar function. The study is a cross-sectional study. We hope to include 24 patients with SMA type II-III and investigate them with MRI T1- and Dixon-imaging, motor function measure 32 (MFM32), lung function, the bulbar rating scale, a timed swallowing test, and questionnaires on swallowing and talking. We will make a heatmap of the involved muscles and correlate the findings to the type of SMA, number of survival motor neuron 2-copies, MFM32 score, and questionnaires. The study is ongoing and expected to end in the Summer of 2024. Results will be presented at the conference.