CLINICAL, ELECTROMYOGRAPHIC, AND ULTRASONOGRAPHIC ASSESSMENT OF FOCALNEUROPATHIES

The study was intended to evaluate the diagnostic value of muscle ultr asonography in the diagnosis of focal neuropathy. Two hundred four pat ients with possible unilateral injury to nerve roots, plexuses, and ne rves extremity were examined prospectively by means of manual muscle t esting, electromyography (EMG), and muscle ultrasonography. These find ings were compared with those of 36 control subjects. Pathologic spont aneous activity correlated very closely with abnormal ultrasonographic findings, especially with increased muscular echointensity. Ultrasono graphy was as sensitive as manual muscle testing and EMG in the detect ion of muscle involvement. Ultrasonography and EMG were complementary. In about 15% of muscles, only one of the two techniques revealed path ologic findings. Increased muscle echointensity was seen in 79% and mu scle atrophy in 48% of muscles assessed to be abnormal. The first ultr asonographic abnormalities appeared 10 days and pathologic spontaneous activity 18 days after acute injury. Ultrasonography was slightly but significantly less reliable than EMG. Muscle ultrasound can help in v isualizing anatomic abnormalities such as muscle atrophy and mesenchym al abnormalities in nerve root, plexus, and nerve lesions.