Electrodiagnosis vs. Pathology II: Nerve

J Korean Assoc EMG Electrodiagn Med 2010;12(1):1-7.
Published online June 1, 2010.

Abstract

Although electrophysiological study (Nerve Conduction Studies/EMG) is among the most sensitive and reliable approaches to detect and to characterize certain aspects of nerves disease, it is important for physicians to appreciates that EMG has limited value in (1) inferring symptoms and neuropathic deficit, (2) inferring involvement of small diameter fiber, (3) inferring underlying biochemical or other pathophysiological derangement, (4) inferring the presence and type and pathologic alteration in single fibers or Schwann cell, or (5) inferring interstitial pathologic abnormalities. For these purpose, an adequate neurological history taking and examination, delicate histologic study of nerve, quantitative autonomic test, and a variety of laboratory examination are usually needed. The purpose of this article is not to diminish EMG or to elevate the procedure of nerve biopsy, rather to provide a conceptual framework for how these techniques and the clinical and laboratory examinations can be used together in the assessment and follow up of neuropathy.

Key Words: Nerve conduction studies, EMG, Nerve biopsy