Subdural patch graft technique for watertight closure of large dural defects in extended transsphenoidal surgery

OBJECTIVE: The most common postoperative complication of the transsphenoidal approach is cerebrospinal fluid (CSF) rhinorrhea. If the dura is widely opened beyond the sellar floor and massive intraoperative CSF leakage is encountered, then the conventional packing method, in which the sella turcica is filled with pieces of fat or muscle, demonstrates a relatively high incidence of CSF rhinorrhea. For more reliable prevention of postoperative CSF leakage, we developed a method for watertight closure of large dural defects. METHODS: For 34 consecutive patients with suprasellar tumors, we performed tumor resection via an extended transsphenoidal approach, in which the surgical window in the sellar floor was extended to the planum sphenoidale to expose the suprasellar cistern. The patients were retrospectively divided into three groups according to the dural defect closure technique used. Group I consisted of the first two patients, whose large dural openings were closed with a conventional fat-packing method. Group II consisted of the next 10 patients, whose large dural defects were patched with fascia and sutured with 5-0 nylon, in a watertight manner. Group III consisted of the last 22 patients, who underwent watertight dural closure with a new knot-tying technique and a double-layer patch graft, which generously covered the dural defect of the cranial base with subdural placement. In Group III, intracranial CSF compressed the patch graft against the cranial base and sealed the gap between the patch graft and the cranial base in a watertight manner. The double-layer patch graft was composed of autologous fascial membrane and a commercially available, expanded polytetrafluoroethylene dural substitute. RESULTS: Postoperative CSF leakage was noted for 50% of the patients in Group I, 30% of the patients in Group II, and 9% of the patients in Group III. The time required for dural closure for Group III was approximately 50% shorter than that required for Group II (45.9 +/- 12.4 min versus 93.5 +/- 19.1 min, P < 0.001). CONCLUSION: The subdural double-layer patch graft technique is simple and reliable for the prevention of CSF rhinorrhea after transsphenoidal surgery associated with a widely opened dura.