Assessment of the neurophysiologic examination in the earlier diagnosis of amyotrophic lateral sclerosis

摘要

We evaluated the role of neurophysiologic examination when the patients with amyotrophic lateral sclerosis (ALS) were first presented to neuromuscular clinic for a definitive opinion. Motor evoked potentials (MEPs), nerve conduction study and needle EMG were examined in 31 patients. The increase of the threshold of MEPs and the central motor conduction time (CMCT) was recognized in 52.9% of the patients with hyperreflexia, 28.6% of them without hyperreflexia and 45.8% of all 31 patients. The decrease of the amplitude of MEPs/M ratio was recognized in 66.7% of patients with hyperreflexia, 58.3% of them without hyperreflexia and 62.5% of all 31 patients, In the first time of examination, 40% of the clinically definite ALS patients coincided with electro-physiological features of definite primary lower motor neuron degeneration of El Escorial revised criteria (1998). At the first presentation to the hospital, many patients with ALS were not considered to fulfill El Escorial revised EMG criteria. Neurophysiologic examination should be made repeatedly in the earlier diagnosis of ALS.