Nasal cerebral heterotopic tissue (nasal glioma) in the adult: a rare cause of primary cerebrospinal fluid rhinorrhea

BACKGROUND: Nasal cerebral heterotopia is a congenital lesion that is mainly detected in early childhood. The rare cases of this disorder found in adult patients are located intranasally. A common symptom is compromised nasal air passage. Clinical findings include polypoid masses in either the nasal cavity or the paranasal sinuses. To our knowledge, primary cerebrospinal fluid (CSF) rhinorrhea has been reported only twice in these patients. PATIENT: A 64-year-old female patient presented with CSF rhinorrhea proven by beta 2-transferrin testing. Previous head injury or intranasal manipulation were excluded. Anterior rhinoscopy revealed a watery drainage from the right middle meatus. CT scan showed a defect in the lateral roof of the right ethmoid sinus, approximately 5 mm in diameter; MRI revealed a mass in the right ethmoid and frontal sinuses, penetrating the anterior skull base. The lesion was resected by an extranasal approach. It showed a fibrous connection to the frontal lobe. Histologically, the lesion consisted of neural tissue composed of gray and white matter, both with a normal structuring. Dura and skull base were reconstructed. There were no signs of a CSF leak postoperatively. RESULTS AND CONCLUSIONS: The differential diagnosis of CSF rhinorrhea includes traumatic events and neoplasms, elevated intracranial pressure, and connate lesions as encephaloceles and, in rare cases, nasal cerebral heterotopia.