title: Useful 'sliding-lock-knot' technique for suturing dural patch to prevent cerebrospinal fluid leakage after extended transsphenoidal surgery.
abstract: BACKGROUND
  Postoperative cerebrospinal fluid (CSF) leakage is a major problematic complication after extended transsphenoidal surgery (TSS). Watertight closure of the sellar dura with a fascial patch graft is a method of choice for preventing CSF leakage; however, suturing and knotting in a deep and narrow operative field is technically challenging and time consuming. To present a simple and effective knotting technique named the 'sliding-lock-knot' technique, in which the knot can easily be slid to the suturing point and tied automatically using only a single string, without loosening.
  
  
  METHODS
  We use a 6-0 nylon suture and Mosquito forceps. At first, after putting a stitch, a single knot is made by hand out of the nasal cavity. Then the 'sliding-lock-knot' is made using a forceps as shown in the illustration. The knot slides deep into the operative field through the nostril and it is automatically tied only by pulling a string.
  
  
  RESULTS
  A 73-year-old woman presented with progressive visual deterioration. She had an intra-and suprasellar craniopharyngioma that was compressing the optic chiasm. She underwent an extended TSS, and the tumor was totally resected. The dural defect was closed with a fascial patch graft sutured on the dura using this technique, then covered with a vascularized mucoseptal flap. Neither CSF leakage nor meningitis was encountered during the postoperative period.
  
  
  CONCLUSIONS
  The 'sliding-lock-knot' technique is simple and useful for dural suturing in microscopic/endoscopic extended TSS. This technique is a helpful tool for preventing CSF leakage after this challenging surgical procedure.
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Akutsu
authors.forename: Shingo
authors.initials: S
authors.lastname: Takano
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Akira
authors.initials: A
authors.lastname: Matsumura
keywords: Cerebrospinal fluid leakage; extended transphenoidal surgery; fascial patch graft; watertight closure