ORIGINAL ARTICLE Surgical treatment of trigeminal schwannomas M. Necmettin Pamir & Selçuk Peker & Fatih Bayraklı & Türker Kılıç & M. Memet Özek Received: 16 December 2006 / Revised: 22 March 2007 / Accepted: 28 April 2007 / Published online: 4 August 2007 # Springer-Verlag 2007 Abstract Schwannomas that arise from the trigeminal nerve are rare, but this nerve is the second most frequent intracranial site of schwannoma occurrence next to the vestibular nerve. The advent of microsurgical techniques and skull-base approaches has greatly enhanced the surgical management of these tumors, and outcomes have improved markedly. This report documents 18 cases of histologically verified schwan- nomas that arose from the trigeminal nerve and were treated surgically in our clinic between January 1992 and July 2005. The patients were ten women and eight men of age 39.7 years (range, 22–62 years). The tumor was located in the middle fossa (type A) in five cases, in the middle and posterior fossae (type C) in nine cases, in the posterior fossa (type B) in two cases, and in the branches of the trigeminal nerve (type D) in two cases. Total excision was achieved in 17 cases, and there was no mortality in the series. Our results indicate that trigeminal schwannomas, regardless of type, can be removed via skull-base approaches. We present an algorithm for surgical management of trigeminal schwannomas based on our experience and information from the literature. Keywords Cavernous sinus . Schwannoma . Surgery . Trigeminal Introduction Schwannomas are benign neoplasms of peripheral nerve sheaths that arise distal to the oligodendroglial-schwann myelination junction. Trigeminal nerve schwannomas are rare, but this nerve is the second most common intracranial site of occurrence after vestibular nerve origin. Trigeminal schwannomas account for 0.07% to 0.28% of all intracra- nial tumors and 0.8% to 8% of all intracranial schwanno- mas [7, 11, 16, 17, 22, 30]. As noted, these tumors can arise anywhere between the root and the distal extracranial branches of the trigeminal nerve. They produce a variety of symptoms and signs that depend on tumor location and the direction and extent of tumor growth. The aim of surgery in cases of trigeminal schwannoma is tumor extirpation with preservation of cranial nerve function. Introduction of microsurgical techniques and advanced skull-base approaches has led to markedly improved outcomes for surgically treated trigeminal schwannomas [6, 8, 17, 22, 26, 29–31]. This report documents our experience with surgical treatment of these tumors. Patients and methods Eighteen patients with histologically verified trigeminal schwannomas underwent surgical treatment in our clinic between January 1992 and July 2005. Detailed general, ophthalmological and neurological examinations were done in each case. Neurosurg Rev (2007) 30:329–337 DOI 10.1007/s10143-007-0093-5 M. N. Pamir : M. M. Özek Department of Neurosurgery, Marmara University Department of Neurosurgery, Marmara University Neurological Sciences Institute, Acibadem Kozyatagi Hospital, İstanbul, Turkey S. Peker (*) Department of Neurosurgery, Acibadem Kozyatagi Hospital, Inonu Cad. Okur Sk., Kozyatagi, Kadikoy, İstanbul 34742, Turkey e-mail: peker@atlas.net.tr F. Bayraklı : T. Kılıç Marmara University Department of Neurosurgery, Marmara University Neurological Sciences Institute, İstanbul, Turkey