FASCICULATIONS - CLINICAL, ELECTROMYOGRAPHIC, AND ULTRASONOGRAPHIC ASSESSMENT

Widespread fasciculations are an important clinical sign in, for examp le, degenerative lower motor neuron diseases (LMND). Usually they are detected by clinical inspection and electromyography. Recently myosono graphy has been proposed for the detection of fasciculations. This pro spective study compares the value of these three modes of examination in patients with degenerative LMND. Seventy healthy control persons an d 34 patients (11 women, 23 men; aged 43-78 years; median age 60.5) wi th LMND were included in the study. All participants were subjected to thorough visual screening for the presence of fasciculations. Fourtee n muscles were examined bilaterally by myosonography and a median of 8 muscles were screened electromyographically (only in the patients); t he investigators were blinded to the other findings. Clinical inspecti on and ultrasonography exhibited fasciculations in up to 5 and 8 muscl es, respectively, in 8 healthy persons. Ultrasonography demonstrated f asciculations in all patients, clinical inspection in all but 2, and e lectromyography in 26 of 33 patients (1 patient was not examined elect romyographically). Comparing the three methods, clinical observation r evealed fasciculations in 42%, electromyography in 39%, and ultrasonog raphy in 67% of all muscles. Thus, ultrasonography was significantly m ore sensitive than the other techniques (P < 0.001). The interrater ag reement (correlation coefficient) r in respect of the presence or abse nce of fasciculation was 0.71 for the clinical, 0.85 for the electromy ographic and 0.84 for the myosonographic examinations. Ultrasonography and electromyography were more reliable than the clinical examination (P < 0.001 and P < 0.01, respectively). Our study indicates that ultr asonography is more sensitive than clinical and electromyographic exam ination in visualizing fasciculations in patients with LMND. Additiona lly, it is more reliable than clinical examination.