DENERVATED SKELETAL-MUSCLE - MR-IMAGING - WORK-IN-PROGRESS

PURPOSE: To evaluate the change in signal intensity of skeletal muscle s after denervation and to determine the clinical usefulness of magnet ic resonance (MR) imaging in diagnosis of denervation. MATERIALS AND M ETHODS: Denervated skeletal muscles associated with various forms of p eripheral neuropathy and spinal radiculopathy were studied with MR ima ging in 17 patients. RESULTS: On T1-weighted images, signal intensity of denervated muscles was normal in 14 patients and high in three. On T2-weighted images, all denervated muscles showed high signal intensit y on at least one MR image. High signal intensity in the denervated mu scles on T2-weighted images was observed 15 or more days after onset o f paralysis. In two patients, signal intensity of denervated muscles r eturned to normal after relief of paralysis. CONCLUSION. MR imaging is a noninvasive and accurate method for use in diagnosis of denervation and may ultimately eliminate the need for electromyography.