Case report: Magnetic resonance imaging (MRI) appearances of benign schwannoma of the larynx

Abstract

A 30-year-old Ghanaian woman presented with a history of hoarseness of voice since birth which had recently worsened. At laryngoscopy a soft, solid mass was seen filling the left ventricle and expanding into the left supraglonis. The tumour was biopsied and later debulked. Histological examination revealed fragments of a benign schwannoma (neurilemmoma). Immunohistochemistry confirmed the Schwann cell nature of the tumour. Nasendoscopy, 3 months later, showed recurrence of the tumour and MRI was performed before and after enhancement with gadolinium with a view to definitive surgery. MRI was performed on a 1.0T scanner (Siemens, Impact) with a Helmholtz neck coil. Contiguous Tl-weighted images (5mm) (TR 693 ms, TE 17 ms) demonstrated a 2 x 1.5 cm. ovoid nodule involving the left aryepiglottic fold and extending down to the level of the cords (Fig. 1). It is similar in intensity to muscle though a little inhomogeneous. The signal intensity of the lesion is higher than muscle on the proton density (TR 3549ms, TE 22ms) and T2-weighted images (TR 3549 ms, TE 90 ms) (Fig. 2). The edge of the lesion is well defined. The left pyriform fossa is compressed and the vestibule distorted. There is patchy enhancement after intravenous gadolinium (0.1 mmol/kg) given by hand injection (TR 658ms, TE 17ms) (Fig. 3).