[Intraoperative brainstem auditory evoked potential in the microvascular decompression of the 5th and 7th cranial nerves].

Microvascular decompression techniques are rational surgical procedures for treating trigeminal neuralgia and facial hemispasm, with results ranging from good to excellent in 90% of cases. Among the most frequent complications recorded in the literature concerning these decompressions, impairment of the facial nerve and auditory nerve account for 5% to 10% due to mechanical traction and/or vascular injury. The peroperative use of early brain-stem evoked potentials (BAEP) was performed on 17 patients in a series of 325 decompressions of the trigeminal nerve, and on 17 patients in a series of 25 decompressions for facial hemispasm. Such peroperative monitoring is considered to be most important in the surgical technique. The author reports on his experience and results.