Traumatic, iatrogenic, and spontaneous cerebrospinal fluid (CSF) leak: endoscopic repair.

Over the past two decades, Cerebrospinal Fluid (CSF) leak repair has advanced from open invasive intracranial approaches to transnasal endoscopic ones that avoid the traditional morbidities of frontal craniotomy approaches--such as anosmia, intracranial haemorrhage or oedema, seizures, memory deficiencies, and behaviour disorders--reducing morbidity, reducing hospitalisation times and accelerating return to work, and therefore cutting indirect costs. The diagnosis of CSF rhinorrhoea is both clinical and radiological. The presence of CSF in clear nasal drainage should be established by analysis for CSF markers. Localisation of the leak site involves radiological investigation, mainly Computerised Tomography (CT) and Magnetic Resonance Imaging (MRI). In addition to suppressing symptoms, the main goal of the closure of CSF rhinorrhoea is to prevent ascending meningitis. The operative management of cerebrospinal fluid leak is advised in the following circumstances: persistent, posttraumatic CSF leaks after 4 to 6 weeks of conservative treatment; all cases of spontaneous CSF fistulae; cases with intermittent leaks; delayed posttraumatic leaks; cases of CSF leak with a history of meningitis; false CSF rhinorrhoea coming from the petrous bone via the Eustachian tube. The graft material used depends mainly on the authors' experience and did not significantly influence the success rate. The main steps in the surgical procedures do not differ as much from one author to the other: accurate localisation of the defect; creation of a raw surface around the defect to accept the graft and to help in the formation of synechiae to support the seal later; plugging of the defect with fat covered with fascia lata supported by absorbable gelatin and Merocel. The differences between the authors relate to the use of fluorescein to locate the defect, the importance of prophylactic antibiotherapy, the plugging materials, the technique of underlay or overlay grafting, the use of fibrin glue and the need for lumbar drainage. The success rate for endoscopic repair of CSF rhinorrhoea is high: approximately 90% at the first attempt. Recent reports in the literature highlight the group of patients with spontaneous idiopathic CSF leak as a group with specific attributes and treatment challenges.