P.84 - Magnetic resonance image in oculopharyngeal muscular dystrophy

Abstract

In the past decade, muscle magnetic resonance image (MRI) has proved to be useful for diagnosis and follow-up in many muscle dystrophies. Oculopharyngeal muscle dystrophy (OPMD) is an autosomal dominant inherited muscle dystrophy characterized by late onset of progressive ptosis, dysphagia and lower limb weakness. There are only a few articles describing the skeletal muscle findings on MRI scans in a small number of patients with OPMD. We are conducting an international and multicentric study with the objective of describing the pattern of fat infiltration in muscle imaging in a large cohort of patients, and correlating it with clinical function. We have analyzed axial T1-W sequences of whole-body MRIs using modified Mercuri scale to estimate the fat infiltration of each muscle. We have also collected clinical data from all the patients analyzed. We present the results of the analysis of the first 20 patients analyzed. Our results show a distinct pattern of muscle involvement. Soleus, tongue and adductor magnus are affected in nearly all patients. Peroneus, gluteus and the posterior compartment of the thigh are also affected in most patients, whereas the gastrocnemius and the vasti are not affected until the late stages of the disease. In the trunk, anterior serratus is the most frequently infiltrated muscle. In contrast to this, upper limbs and pelvic floor muscles are spared in the majority of patients. We have found a positive correlation between clinical situation and muscle MRI changes. In conclusion, the pattern we are describing is consistent among patients with OPMD and different from other dystrophies. Therefore, MRI could be a useful tool for the diagnosis of oculopharyngeal muscle dystrophy.