Intramedullary tumours in patients with neurofibromatosis type 2: MRI features associated with a favourable prognosis

Abstract

To assess the magnetic resonance imaging (MRI) features and natural history of intramedullary tumours in patients with neurofibromatosis type 2 (NF2). Eleven NF2 patients with intramedullary spinal cord tumours were identified from the database of the multidisciplinary NF2 clinic. All the imaging studies of these patients were individually reviewed by two neuroradiologists to evaluate the size, number, location, imaging characteristics, and interval growth of the intramedullary tumours. Two of the 11 patients had lesions that required surgery. Both these lesions were in the cervical region, and extended over three and five segments respectively. Nine patients with a mean imaging follow-up period of 77 months had lesions that remained stable, apart from the development of small peritumoral cysts in three. The lesions were well circumscribed, often multiple, usually less than 1cm in diameter, and were most frequently found in the cervical cord. The majority of intramedullary tumours in NF2 patients are very slow growing and share certain MRI features that differ from those of progressive or symptomatic lesions.