Very delayed CSF leak in patients after craniotomy for resection of skull base tumors

Cerebrospinal fluid (CSF) leak is a potentially dangerous neurosurgical complication. Delayed CSF leak has already been described after trauma, radiation therapy and endonasal transsphenoidal surgery for Sella turcica pathologies. Still, very few reported cases describe delayed CSF leak after craniotomy for tumors. We present our experience with patients showing delayed CSF leak after skull base tumor resection.

Data for all tumors resected from the skull base region from January 2004 to December 2018 was retrieved from the surgeon's prospective database and supplemented with a retrospective file review. Patients who presented CSF leak within the first 12 months after surgery and those with a history of trauma or radiation-based treatment to the skull base region were excluded from the study. Epidemiology, clinical presentation, previous surgical approach, pathology, interval between craniotomy and CSF leak and proposed treatment were analyzed.

Overall, more than two thousand patients underwent surgery for resection of skull base tumors during the study period. Six patients (two male, four female; mean age 57.5 years, range 30-80) presented with delayed CSF leak, including five (83%) who presented with bacterial meningitis. After skull base tumor resection, CSF leak developed in a mean of 72 months (range 12-132). Three patients underwent retrosigmoid craniotomy, two for resection of cerebellopontine angle epidermoid cyst and one for resection of a petro tentorial meningioma; one had trans petrosal retrolabyrinthine craniotomy for resection of a petroclival epidermoid cyst; one had far lateral craniotomy for resection of a foramen magnum meningioma; and one had pterional craniotomy for resection of a cavernous sinus meningioma. All patients underwent surgical re-exploration and repair. CSF leak was managed with mastoid obliteration in five patients and skull base reconstruction with fat graft in one.

Recognition of very delayed CSF leak as a potential complication after resection of skull base tumors may be useful tool in long-term patient management. In our experience, these patients usually present with bacterial meningitis. Surgical options should be considered as a definitive treatment.