Intracranial Neuroenteric Cyst in the Cerebellopontine Angle with Calcified Cyst Wall: A Rare Case Report.

Neuroenteric cysts (NCs) are rare benign lesions believed to originate from ectopic endodermal tissue. They are lined by gastrointestinal or respiratory epithelium capable of secreting mucin. Although most frequently located within the spinal canal, intracranial NCs are exceedingly rare and typically occur ventral to the brainstem. We report a case of a young female patient with an NC located in the cerebellopontine angle-an atypical site-exhibiting uncommon imaging features. Radiological evaluation revealed cystic contents with signal intensities similar to cerebrospinal fluid, a partially calcified cyst wall, and mild contrast enhancement. Extensive calcification resulted in firm adhesion to adjacent neurovascular structures. Surgical resection was performed, preserving a small calcified plaque that was tightly adherent to critical surrounding tissues. This case underscores the importance of including NCs in the differential diagnosis of intracranial cystic lesions, particularly when cyst wall calcification is present. Calcification can significantly influence surgical planning and increase the risk of adhesion to neurovascular structures, necessitating cautious dissection.