PRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 95 No. 8 August 2002
An Extracranial Trigeminal Neurinoma Expanding
into the Infratemporal Fossa; A Case Report
Hiromi Sugiyama, Kazuo Gouzu, Norihiko Ishikawa and Seiji Kishimoto
(Tokyo Medical and Dental University)
Masahiro Kawana
(Niigata University)
A 21-year-old male with an extracranial trigeminal neurinoma is presented. Swelling of the pre-auricular region was noted in 1998 and the patient consulted in one of our clinics. CT scan and MRI demonstrated a lesion consisting of five linked nodules that seemed to extend along the extracranial course of the mandibular nerve, passing between the medial and lateral pterygoid muscles and extending laterally toward the medial aspect of the compressed parotid gland. The anterior condyle of the mandible was displaced. Pathological diagnosis by fine needle aspiration biopsy showed neurinoma. The tumor seemed to originate from the mandibular nerve. After the diagnosis was established, the patient was observed for 2 years without surgery. In 2000, repeat CT examination demonstrated that the tumors had enlarged and erosion of the oval foramen had progressed. Therefore, surgical treatment was indicated. Surgery was performed in September 2000. A bicoronal skin incision was made with extension to the periauricular and cervical area. An infratemporal extradural approach combined with a zygomatic and mandibular osteotomy. The moniliform tumor was totally extirpated. Postoperatively, the patient displayed sensory defects of the mandibular nerve and trismus. The latter was improved by rehabilitation one year postoperatively.
Key words : extracranial, trigeminal neurinoma, infratemporal fossa