Magnetic Resonance Neurography Findings in Idiopathic Neuralgic Amyotrophy

Abstract

Idiopathic neuralgic amyotrophy (INA) is known as Parsonage-Turner syndrome or idiopathic brachial plexitis and is characterized by sudden onset of severe limb pain, followed by weakness and atrophy of limb. There is no specific tests for the diagnosis of INA. The diagnosis of INA is mainly dependent on the clinical history and electrodiagnostic study. It is often confused with more common disorders such as acute cervical radiculopathy, rotator cuff tear, or acute calcific tendinitis. A few recent reports have revealed that magnetic resonance image (MRI) of brachial plexus and shoulder can be helpful in the diagnosis of INA. We report two cases of classic INA in which MRI enhanced specificity and confidence in the diagnosis. MRI of the brachial plexus and corresponding limb as well as cervical spine should be included in patients clinically suspected of INA.