An unusual case of large posterior fossa neurenteric cyst involving bilateral cerebellopontine angle cisterns: report of a rare case and review of literature.

Background: Intracranial neurenteric cysts are rare cystic masses of endodermal origin lined with mucin producing low columnar or cuboidal epithelium. Approximately 141 cases have been reported so far. Most of the posterior fossa neurenteric cysts are typically small, located anteriorly to the brainstem in the midline or in the cerebellopontine angle cistern area.

Methods: We present a rare, histologically proven case of a large lobulated intracranial neurenteric cyst measuring 4.2 centimeters in the maximal transverse dimension and involving bilateral cerebellopontine angle cisterns. We also present a review of the literature on this uncommon finding.

Conclusions: Imaging features of neurenteric cyst are non-specific and it should be considered in the differential diagnosis for any intracranial extraaxial cystic lesion.