MAGNETIC-RESONANCE-IMAGING IN THE DIAGNOSIS OF NEUROMUSCULAR DISEASES

The classical morphological diagnosis of neuromuscular diseases with muscle biopsy is increasingly combined with muscle imaging methods. The MRI (Magnetic Resonance Imaging) of the muscle exceeds muscle CT and myosonography in sensitivity and specificity. Sample errors of the muscle biopsy in sense of false negative results or very much alterated tissue can be avoided with MRI guided muscle biopsy. In inflammatory myopathies MRI of the thighs reveals a muscle edema frequently accentuated in the vastus lateralis muscle. The specifity of the muscle edema in the MRI is unknown. The signal alteration in MRI of polyneuropathies and motor neuron diseases points out that muscle fibers are converted into connective tissue. Muscle atrophy and missing muscle hypertrophy are linked to the amount of mesenchymal changings in these diagnoses.