Diagnosis of neurinoma in the region of the jugular foramen--a case report.

Neurinomas in the region of the jugular foramen are extremely rare, are difficult to diagnose before surgery, and have seldom been described in the literature. The typical jugular foramen syndromes (Collet-Sicard syndrome, Vernet's paralysis) may be caused by many various disorders. The diagnostic problems are illustrated using one of our cases as an example. The differential diagnosis was made before surgery using currently available radiologic techniques. The tentative diagnosis "neurinoma of the hypoglossal nerve" was confirmed intraoperatively and histologically.