Thoracic and lumbar meningocele in neurofibromatosis type 1. Report of two cases and review of the literature.

We report two cases of ventrolateral thoracic and lumbar meningoceles associated with neurofibromatosis type 1, and present a review of the literature. Thoracic and lumbar meningoceles are rare lesions which are associated with neurofibromatosis in 60% to 85% of cases. Large meningoceles may cause pain, neurological signs, or respiratory complaints when located intrathoracically. Surgery is indicated in such cases, as well as when small meningoceles enlarge with time. The etiology of meningoceles in neurofibromatosis remains controversial. The authors postulate that ventrolateral lesions of the thoracic and lumbar spine are secondary to congenital mesodermal dysplasia and hypoplastic bone changes. MRI is the diagnostic method of choice, since it most adequately visualizes the pathological anatomy of the spinal cord, meninges, and adjacent structures in every sectional plane. CT scans are particularly useful in assessing the spinal bony changes.