Pneumocephalus from a frontal-ethmoid neurilemoma

Area of Science:

• Neurology
• Otolaryngology
• Neurosurgery

Background:

• Neurilemomas are typically benign nerve sheath tumors.
• Paranasal sinus tumors are uncommon, and neurilemomas in this location are exceptionally rare.
• Pneumocephalus, or air within the cranial cavity, is a serious condition often associated with trauma or surgery.

Observation:

• A 68-year-old male presented with neurological symptoms including memory lapse, character changes, and gait instability.
• Skull imaging revealed spontaneous pneumocephalus and a bony lesion in the right ethmoid sinus.
• Initial diagnosis of the ethmoid lesion was osteoma, suspected of causing dural erosion.

Findings:

• Histopathological examination identified the ethmoid lesion as an osteoid reaction surrounding a primary neurilemoma, not an osteoma.
• This represents the first reported instance of a paranasal sinus neurilemoma associated with pneumocephalus.
• The neurilemoma was successfully excised using a Lynch surgical approach.

Implications:

• Highlights the importance of considering rare tumors in the differential diagnosis of paranasal sinus lesions presenting with neurological symptoms.
• Demonstrates that neurilemomas, though rare in the paranasal sinuses, can lead to significant intracranial complications like pneumocephalus.
• Successful surgical management of this rare condition resulted in a positive long-term outcome for the patient.