Cerebrospinal Fluid Leak and Pneumocephalus after FESS

The patient is a 75-year-old male with a history of chronic rhinosinusitis for years, status post balloon sinuplasty with recurrence of sinonasal symptoms including chronic nasal congestion, recurrent sinusitis, facial pressure, frontal headaches, and post nasal drip which had been refractory to daily large-volume saline irrigations, topical corticosteroids and several courses of antibiotics and prednisone. Functional endoscopic sinus surgery (FESS) was recommended and the patient underwent bilateral maxillary antrostomies, anterior ethmoidectomies, and frontal sinusotomies by an outside otolaryngologist. The patient called the office on postoperative day 1 (POD1) and noted left greater than right copious nasal discharge and conservative management was advised. On POD2, he then developed severe bitemporal headache, nausea, vomiting, and chills. Significantly, he reported his headache was exacerbated when standing and improved when lying down. He was advised to proceed to the emergency room, where postoperative imaging was consistent with extensive pneumocephalus and an unrecognized skull base bony defect at the junction of the fovea ethmoidalis and lateral lamella of the cribriform plate at the time of FESS (Fig. 11.1). Otolaryngology was consulted, and the patient was urgently taken to the operating suite for endoscopic repair of the skull base defect and cerebrospinal fluid (CSF) leak. A 2 mm × 2 mm defect was identified just superior to the anterior ethmoid artery, along the lateral lamella, without direct arterial injury (Fig. 11.2). The area around the defect was prepared by first ligating the anterior ethmoid artery using bipolar cautery, removing the surrounding remnant ethmoid cells along the skull base and then clearing a 3–4 mm circumference of mucosa around the defect. This skull base defect was repaired using a free mucosal overlay graft harvested from the contralateral nasal floor and secured with fibrin glue and resorbable nasal packing. Postoperatively, he noted improvement of his headache and he was subsequently discharged in stable condition and has been doing well at follow-up. He has smooth re-mucosalization of the left ethmoid skull base (Fig. 11.2c).