Disclosures: Benjamin T. Buterbaugh, DO: No financial relationships or conflicts of interest

Case Diagnosis: 62-year-old female with motor band sign on MRI

Case Description or Program Description: The patient presented with progressive quadriparesis, dysphonia and dysphagia. Patient had been previously diagnosed with left hemiparesis which was attributed to a magnetic resonance imaging (MRI) negative ischemic stroke. Subsequently, patient progressively began losing function in her right extremity followed by dysphagia and dependence with ambulation and transfers over a 1-year period.

Setting: Academic Acute Care Hospital

Assessment/Results: Full laboratory workup was unremarkable. MRI brain demonstrated findings of curvilinear bands of low signal in the cortical gray matter on T2-weighted MRI, consistent with motor band sign. Further physical exam revealed dysphonia, diplegia, hyperreflexia, tongue wasting, tongue fasciculations, weak cough, quadriparesis, and atrophy throughout. Frontal release signs were also present. Electromyography showed active denervation and chronic reinnervation in 3 spinal segments consistent with motor neuron disease. Patient was started on rilouzole and was set up with the amyotrophic lateral sclerosis (ALS) clinic.

Discussion (relevance): While the Gold Coast Criteria can help a clinician diagnose ALS, there are other clues that can assist in diagnosis. Motor band sign is a MRI finding due to iron accumulation in the microglia of the motor cortex producing curvilinear bands of low signal in the cortical gray matter that can be seen in at least 5% of patients with ALS on T2-weighted-Fluid-Attenuated Inversion Recovery Sequence. While this finding is not specific for ALS, it is a clue that motor disease is present.

Conclusions: Motor band sign can be seen on MRI and should trigger a full ALS workup including electrodiagnosis. Early diagnosis of ALS will become increasingly important as new treatments become more effective at modifying disease course.

Level of Evidence: Level V

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PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/motor-band-sign-on-mri-a-unique-clue-for-possible-als-diagnosis-a-case-report/