Disorders Involving a Persistent Craniopharyngeal Canal: A Case Series

Background A persistent craniopharyngeal canal (PCC) is a rare embryologic remnant that presents as a well-corticated defect of the midline sphenoid body extending from the sellar floor to the nasopharynx. Our case series describes three unique presentations of this scarcely reported congenital midline defect and their subsequent management.

Cases Case 1 describes a 56-year-old woman who underwent an endonasal endoscopic removal of what was thought to be a mucous retention cyst of the nasopharynx. The patient subsequently presented to our institution with delayed clear fluid rhinorrhea and meningitis. She was found to have a cerebrospinal fluid (CSF) leak from a PCC encephalocele. Case 2 describes a 41-year-old woman with a history of menstrual irregularities who underwent magnetic resonance imaging for evaluation of a pituitary lesion. She was instead found to have a massive encephalocele descending within a PCC canal and terminating as a mass in the nasopharynx. Case 3 describes a 14-year-old girl with a history of macrocephaly, cerebral aqueduct stenosis, and hydrocephalus as an infant, who was later found to have severe type II Chiari malformation and a PCC containing air bubbles, suggestive of pneumoencephalocele. In all cases, the defect was repaired primarily without complications.

Discussion PCCs are associated with diverse pathology and may present in various ways. Cases 2 and 3 in this series are representative of the larger subset of patients in the literature who present with the defect incidentally; either during work-up of symptoms unrelated to the malformation or in association with other congenital malformations. The presentation of a persistent craniopharyngeal canal with CSF leak as in Case 1, however, is exceedingly rare. Regardless of the manner of presentation in our series, a standard approach to diagnosis with preoperative imaging and subsequent transnasal endoscopic repair of the skull base defect could be undertaken and yielded successful patient outcomes.

Conclusion The persistent craniopharyngeal canal is a rare congenital anatomic variant and clinical presentation may vary based on the size and contents of the malformation. Thus, careful review of preoperative radiology is critical to the management. Nonetheless, subsequent surgical repair and reconstruction are associated with excellent postoperative outcomes.