Electrodiagnostic findings in the early stages of Bell's palsy and Ramsay-Hunt's syndrome.

The incidence of denervation, as determined electrodiagnostically (nerve excitability test and electroneuronography), was analysed during the course of the disease in 150 patients with Bell's palsy and 45 with Ramsay-Hunt's syndrome. Of all 150 patients, 14.2% of those with Bell's palsy and 44% of the patients with Ramsay-Hunt syndrome either showed denervation at the time of the initial examination or developed denervation from neurapraxia within 3 weeks after the onset of paralysis.