Shahid Khan
This study is to share our experience of an effective dural repair technique, which we have utilised to minimise the incidence of postoperative CSF leakage in patients undergoing microvascular decompression (MVD) for Trigeminal Neuralgia and Hemifacial Spasm. Between 1987 and 2018, 134 patients had microvascular decompression, mainly for Trigeminal Neuralgia and Hemifacial Spasm in our unit. All our patients having posterior fossa MVD using the technique described by Janetta, had an apparently watertight repair of the dura at the end of the operation. We describe our technique using Duraguard ® and Histacryl® glue. The post-operative outcome of the duraplasty was assessed retrospectively by case note review. Of 134 patients, 129 (96.2%) had no post-operative CSF leakage. Only 5 (3.7%) of the patients experienced post-operative CSF leakage.(3 from the wound, 2 from the nose). We conclude that dural repair using the described technique utilising a dural substitute (Duraguard) and Histacryl glue is safe and effective in preventing post operative CSF leak following MVD. Cerebrospinal fluid (CSF) leakage is one of the most common complications after microvasculardecompression (MVD) for neurovascular cross compression syndrome, including hemifacial spasm(HFS), trigeminal neuralgia, and gloss pharyngeal neuralgia. Current treatments comprise reducing CSF pressure by continuous lumbar drainage or repeated spinal taps and administering antibioticsto prevent infections. Failure of these treatments finally requires additional surgical intervention. Even after these treatments, fatal situations, such as pseudomeningocele, meningitis, and abscessformation, may complicate the postoperative course and lead to permanent deficits. To prevent CSF leakage after MVD, it has been highly emphasized by Peter J. Jannetta to ensurewatertight dural closure. Additionally, primary dural closure (primary reapproximation andsuturing of the dural edges) is the best seal without the introduction of autologous grafts of fat orartificial dural substitutes . However, this is not always possible due to shrinkage of the dura materonly from exposure during surgery and/or electrocautery for dural bleeding.Although many dural replacements have been introduced and used to ensure watertight duralclosure, no substitute has proven to be complication-free in a large clinical trial, even suggesting somebenefit . Therefore, primary dural closure should be attempted during the closure of craniotomyor craniectomy for MVD.In this study, clinical outcomes related to CSF leakage after retrosigmoid craniectomy with MVDwere analyzed after using a simple technique to maintain the integrity of the dural flap, allowing forprimary dural closure. Between 2010 and January 2019, 360 consecutive cases were treated with retrosigmoid craniectomy,with MVD for HFS in 309 (85.8%) patients, trigeminal neuralgia in 50 (13.9%) patients, andglossopharyngeal neuralgia in one (0.3%) patient, and they were followed up more than one monthafter surgery. A retrospective review of medical records was performed to identify patients whoexperienced CSF leakage, including CSF rhinorrhea, otorrhea, pseudomeningocele, and/or incisionalleak, during the initial hospital stay or by the first postoperative clinical follow-up usually at onemonth after surgery. The primary outcome was the primary dural closure rate using the surgicaltechnique described below. Additionally, the author defined the secondary outcome as persistent CSFleakage that needs management with additional neurosurgical intervention such as continuous lumbardrainage, repeated spinal taps, and/or neurosurgical revision operation. Moreover, all patients with symptomatic CSF leakage were examed and assessed by otolaryngologists.We collected all of the patient data based on information contained in hospital electronic medicalrecords and followed the case record form, which was approved by the institutional review board.As a retrospective study, there was no risk to the subjects (minimum risk study), and the IRB committee approved (B-1903-528-105) the exemption of consent from the subjects. In this article, the author describes a straightforward and rapid technique to prevent CSF leakagethat can occur after MVD through retrosigmoid craniectomy. To prevent CSF leakage, the surgeonshould try various methods at each stage of surgery, but primary closure is fundamental. Besides, theauthor describes the surgical technique that enables primary dural closure in detail. After that, theextra fibrinogen/thrombin-based collagen fleece (TachoComb®; Nycomed, Linz, Austria) is appliedto the dural incision site after use for hemostasis, and to the opening of the mastoid air cell, whichenhances the watertight primary dural closure. Then, cranioplasty using artificial bone cement, whicheliminates dead space on the craniectomy site, is performed. Finally, the soft tissues, from muscles tothe skin, are closed watertight. With each step, the author could significantly reduce the occurrence ofpersistent CSF leakage that requires lumbar drainage or surgical intervention. It is crucial to achieving tight and reliable dural closure while performing retromastoid craniectomywith MVD.
