Intracochlear schwannoma

Abstract

Intralabyrinthine schwannomas are benign, slow-growing tumors that originate from Schwann cells lining the terminal ends of the cochlear and vestibular nerves. Magnetic resonance imaging (MRI) with gadolinium is considered the best diagnostic tool for this disease. Kennedy et al proposed a classification system, based upon the MRI observations, that identifies seven different classes according to the site of the tumor: intravestibular, intracochlear, intravestibulocochlear, transmodiolar, transmacular, transotic, and tympanolabyrinthine. A case of a patient undergoing a 2-year follow-up with serial MRI and managed with a wait-and-see strategy is described. The rationale of the diagnosis and the different treatments of choice are discussed.

Keywords: Intralabyrinthine schwannoma; MRI; follow-up; surgery.

Figure 1

Heavily T2-weighted fast spin-echo images in the axial planes (A, B, C). A normal basal turn of the left cochlea. A schwannoma occupies the posterior parts of both scalae of the second turn. Normal fluid in the scala tympani of the anterior second turn (arrow). The first turn is full, although it opens somewhat at the apex.

Figure 2

T1-weighted (A) and gadolinium-enhanced T1-weighted (B, C) images in the axial planes. There is a strongly enhancing schwannoma in the first and second cochlear turns.