Usefulness of muscle denervation as an MRI sign of peripheral nerve pathology.
Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non-compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion-recovery and fat-suppressed T2-weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1-weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders.
Lisle
D A
DA
Department of Medical Imaging, Redcliffe District Hospital, Redcliffe, Queensland, Australia. dlisle@bigpond.net.au
Johnstone
S A
SA
D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009121:Muscle Denervation; D018482:Muscle, Skeletal / Q000294:innervation*; D016491:Peripheral Vascular Diseases / Q000175:diagnosis*