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.

[Labyrinthine fistulae and cholesteatoma]. / Fistules labyrinthiques et cholestéatome.

The case notes of 33 patients with labyrinthine fistulae have been studied; they have been found in 10% of cholesteatomas. The usual site is the lateral semicircular canal. Only 17 patients experienced vertigo, 2 had total deafness, and 14 others had a mixed deafness. Scanning with fine cuts in both the axial and coronal planes demonstrates the lesion definitively in 70% of cases, but the fistula may be discovered only at operation, either in the lateral semicircular canal, or especially at the level of the oval window (5 cases). The authors usually use the closed technique (26 cases), and always seek to remove the matrix in its entirety, followed by the use of bone powder to close the fistula. In 2 patients there was a loss of hearing on bone conduction at 4 and 8 KHz, and only one had total loss of hearing. No patients had vertigo persisting after 6 months. The indications and results are compared with those found in the literature. It now seems unusual to experience postoperative sensory-neural hearing loss provided that the presence of a fistula is recognised early on, and that the covering of squamous epithelium is removed completely atraumatically at the last part of the operation.

[Failures after tympanoplasty]. / Les échecs après tympanoplastie.

Failures and pitfalls in chronic ear surgery have been studied. The material consists of a retrospective study of 616 cases of tympanoplasty. The results were mainly analysed into cases of iatrogenic cholesteatoma (23), labyrinthine fistulae (25) and disruption of ossicular chain (46). The incidence of fistula into the semi-circular canal is high with cholesteatoma, and careful removal of the matrix is recommended to prevent sensorineural hearing loss. Disarticulation of the incudo-stapedial joint is performed to eradicate attic cholesteatoma and protect the cochlea. However, this procedure gives a risk of damage to the inner ear. The frequency and nature of sensorineural losses following chronic ear surgery have been discussed. Surgical precautions are advocated to prevent inner ear damage or other iatrogenic complications.