Observations on the etiology of trigeminal neuralgia, hemifacial spasm, acoustic nerve dysfunction and glossopharyngeal neuralgia. Definitive microsurgical treatment and results in 117 patients.

Microsurgical observations have been made of the cranial nerve root entry or exit zones 117 patients operated upon for the treatment of hyperactive-hypoactive dysfunction syndromes (trigeminal neuralgia, hemifacial spasm, acoustic nerve dysfunction, and glossopharyngeal neuralgia). Cross-compression or distortion of the appropriate nerve root at its entry or exit zone was noted in all patients. This compression or distortion was usually caused by normal or arteriosclerotic, elongated arterial loops, it was usually relieved by decompressive microsurgical techniques. A small percentage of patients were found to have compression of the nerve root at the entry-exit zone by a tumor, a vein, or some other structural abnormality; they were relieved by tumor excision or other measures as described. Relief was gradual postoperatively if the treated nerve was not stroked or manipulated at operation but it was immediate if the nerve was manipulated. Preoperative evidence of decreased nerve function improved postoperatively.