Abstract
To evaluate the reliability of conventional tests for facial nerve degeneration, comparison of the thresholds and correlation with prognosis were made between the conventional percutaneous and direct stimulation methods in 11 cases of facial palsy in which decompression operation were performed and follwed up for more than 6 months.
Although all cases showed the findings of complete or high degree nerve degeneration with the preoperative percutaneous stimulation test, the threshold for the intraoperative direct stimulation test varied from 4 volts (normal) to more than 30 volts.
The results of intraoperative direct stimulation test correlated well with prognosis (degree of improvement of palsy score). The cases with thresholds within 30 volts showed good recovery of palsy (more than 32 points of palsy score), while the cases with thresholds more than 30 volts showed plasy scores less than 28 points except one case.
Our results indicates that the direct stimulation method is better than the percutaneous stimulation method as an electrodiagnostic test for nerve degeneration.
