Endoscopic-assisted surgical repair of ear cerebrospinal fluid leakage through a subtemporal craniotomy

CSF fistula involves abnormal leakage of cerebrospinal fluid (CSF) from its normal pathways, typically from high- to low-pressure areas at the base of the skull. It requires an osteomeningeal breach, causing discomforts such as headaches and abnormal drainage. Temporal bone CSF leakage often results from trauma or chronic otitis media, and its surgical treatment is often delayed. The application of endoscopes in skull base procedures has become increasingly common, offering new ways to improve visualization during performance. Endoscopic tools provide a broad view, sharp image quality, enhanced magnification, and the advantage of visualizing areas that are typically hard to see directly.

CSF leaks in the temporal bone can be challenging to diagnose, with subtle symptoms that can go undetected for years. Imaging techniques such as computed tomography (CT) and magnetic resonance imaging are used for diagnosis, with CT cisternography being the most reliable. Surgical repair may be necessary in certain cases. Most patients do not require surgery, as conservative management is effective. Surgery is considered for severe symptoms. Absolute contraindications include conditions that prevent general anesthesia, while relative contraindications include vestibular issues and migraines. Endoscopic surgery involves a light source, rigid endoscope, and high-definition camera. The defect is repaired using materials such as bone wax, fat, and fibrin glue. Surgery is performed under general anesthesia with a small incision behind the ear, and the skull base is reconstructed.

Once the patient can ambulate and tolerate a diet, they can be discharged (average hospital stay is 2 days) on 60 mg of oral prednisone daily for 2 weeks followed by a 1-week taper. During postoperative course, patient's course was uncomplicated and there was no evidence of CSF leakage at 24 h, nor at the review 2 weeks later in the outpatient clinic.

CSF leaks of temporal bone origin are rare and should be considered in patients with non-resolving outer ear effusion or meningitis. Temporal bone CT represents the most valuable imaging modality for diagnosis and preoperative surgical planning. Isolated dural defects of the tegmen tympani may be repaired through subtemporal approach through a craniotomy. Endoscope-assisted surgery leads to an elevated efficacy of defining precisely the site of the bone defect.