Neurophysiological methodologies: diagnosis of peripheral nerve disease and assessment of pharmacological agents

Recent developments in the field of neurophysiology have led to the refinement of neurophysiological techniques, enabling clinical investigators to assess neuropathy patients with greater precision. In addition to conventional nerve conduction studies and electromyography, novel axonal excitability techniques and quantitative sensory testing may be used to improve diagnosis and to characterize and serially monitor peripheral nerve disorders. A significant expansion in the number of clinical trials being conducted for neurological indications has increased the impetus to further develop neurophysiological measures that reflect the responsiveness to drug therapies. Measures such as motor unit number estimation and the neurophysiological index may facilitate the advancement of compounds in the drug discovery pipeline. This review summarizes several electrodiagnostic and neurophysiological techniques, both conventional and novel, highlighting recent advances that are relevant to disease diagnosis and the assessment of patient response to treatment strategies.