Factors contributing to failure in endoscopic skull base defect repair

Endoscopic repair of skull base (SB) defects is successful in over 90% of cases. Certain factors may contribute to failure of SB repair techniques or need for secondary repair.

Five-year retrospective review of endoscopic SB defect repairs performed by a single surgeon.

Eighty-nine patients undergoing 110 procedures to repair 97 SB defects were evaluated. Etiology of defects included surgical/iatrogenic (64%), spontaneous (17%), traumatic (12%), congenital (6%), and idiopathic (1%). Defects occurred in the sella (41%), sphenoid sinus (18%), ethmoid roof (17%), olfactory cleft (16%), frontal sinus/recess (6%), and middle cranial fossa (2%). Sixty-three patients (71%) underwent primary SB defect repair and 26 patients underwent secondary repair (29%). In revision cases, mean number of prior repair attempts was 1.5 (range, 1-4). Factors potentially contributing to need for secondary SB defect repair included inability to localize SB defect (p =0 .008), development of new SB defect, prior sinus or SB surgery (p < 0.001), prior craniotomy (p < 0.001), prior radiation therapy (p = 0.002), and intracranial infection (p = 0.023). SB defects were successfully closed in 83 patients overall (93%), with success achieved in 97% of primary patients and 85% of secondary patients. Of failures, 3 patients required craniotomy for defect closure, 2 patients underwent permanent cerebrospinal fluid (CSF) diversion, and 1 patient has persistent CSF rhinorrhea.

Although endoscopic repair of SB defect remains largely successful, certain factors should alert the surgeon to the potential for failure of repair or need for secondary SB defect repair.