Neurofibromatosis type 2: optic nerve sheath meningioma in one orbit, intramuscular schwannoma in the other.

A highly unusual patient with neurofibromatosis type 2 (NF2) presenting with simultaneous bilateral orbital tumors is described. A 12-year-old girl with a family history of NF2 was examined because of bilateral proptosis. Visual acuities were light perception RE and 20/40 LE. Magnetic resonance imaging studies showed bilateral cerebellopontine angle tumors, a tumor surrounding the right intraorbital optic nerve, and a large left lateral orbital mass mixed with the lateral rectus muscle. The histopathological diagnoses following incisional biopsies were right optic nerve sheath meningioma and left intramuscular schwannoma. The left-sided orbital schwannoma and the right-sided vestibular schwannoma were treated with fractionated stereotactic radiotherapy. This patient enlarges the spectrum of clinical presentations that can be encountered at young age in patients with NF2.