Tension pneumocephalus as a result of endonasal surgery: an uncommon intracranial complication.

Tension pneumocephalus (TP) is a clinical entity characterized by continued build-up of air within the cranial cavity, leading to abnormal pressure exerted upon the brain and subsequent neurologic deterioration, due to development of a mass effect and potentially a herniation syndrome. Intracranial complications of endoscopic sinus surgery (ESS) and other endonasal procedures are fortunately very rare, occurring in less than 3% of cases. We report 4 cases of small bone defects (<3 mm) in the anterior cranial base accompanied by TP, caused by ESS and other endonasal procedures. The pathophysiology and management of this clinical entity is discussed with a pertinent literature. Four patients with small (<3 mm) skull base defects were identified. All patients presented with active cerebrospinal fluid leaks. CT scans showed intracranial tension pneumocephalus. Using image-guided endoscopic techniques, all defects were addressed with multi-layer repair. Closure was achieved in all patients on the first attempt, with an average follow-up of 36 months. Tension pneumocephalus is a rare event that can occur as a result of traumatic or iatrogenic violation of the dura and should be considered in all patients presenting with altered mental status after endoscopic sinus surgery or other surgical and diagnostic procedures that violate either the cranial or spinal dura. Because of the potential for rapid clinical deterioration and death, prompt brain imaging is warranted to rule out the diagnosis, and urgent neurosurgical consultation is indicated for definitive management.