[Prognostic diagnosis of facial palsy with electroneuronography]

We examined the accuracy of electroneuronography (ENoG) as a prognostic indicator in 58 patients with facial palsy: 47 patients with Bell's palsy and 11 patients with Ramsay-Hunt syndrome over a period of one year. For surface recording, the active electrodes were placed over the orbicularis oculi, orbicularis oris, quadratus labii, nasal alae or nasolabial fold, and the indifferent electrode over the same muscle in the opposite side. ENoG over nasal alae showed the most reliable value and the next was orbicularis oris. All other muscles were less reliable. We found that in 87.2% of cases, recovery was satisfactory in Bell's palsy and 63.6% cases in Ramsay-Hunt syndrome. Of the 47 Bell's palsy patients, 38 patients (80.9%) had a response to ENoG over nasal alae of 10% or greater, while 5 patients (45.5%) of the 11 patients with Ramsay-Hunt syndrome. All these patients recovered satisfactorily within four months. Nine of 47 patients (19.1%) with Bell's palsy and 6 of 11 patients (54.5%) with Ramsay-Hunt syndrome had a response of 10% or less. Satisfactory recovery rate among these patients was 33.3%. In conclusion, ENoG over nasal alae and orbicularis oris shows reliable values among other muscles. Patients with responses to ENoG over nasal alae of 10% or greater showed satisfactory recovery.