Assessment of frontal lobe sagging after endoscopic endonasal transcribriform resection of anterior skull base tumors: is rigid structural reconstruction of the cranial base defect necessary?
OBJECTIVE
The endoscopic endonasal transcribriform approach (EETA) is a viable alternative option for resection of selected anterior skull base (ASB) tumors. However, this technique results in the creation of large cribriform defects. Some have reported the use of a rigid substitute for ASB reconstruction to prevent postoperative frontal lobe sagging. We evaluate the degree of frontal lobe sagging using our triple-layer technique [fascia lata, acellular dermal allograft, and pedicled nasoseptal flap (PNSF)] without the use of rigid structural reconstruction for large cribriform defects.


METHODS
Retrospective analysis.


METHODS
Nine patients underwent an EETA for resection of large ASB tumors from August 2010 to November 2011. The degree of frontal lobe displacement after EETA, defined as the ASB position, was calculated based on the most inferior position of the frontal lobe relative to the nasion-sellar line defined on preoperative and postoperative imaging. A positive value signified upward displacement, and a negative value represented inferior displacement of the frontal lobe.


RESULTS
The average cribriform defect size was 9.3 cm(2) (range, 5.0-13.8 cm(2) ). The average distance of postoperative frontal lobe displacement was 0.2 mm (range, -3.9 to 2.9 mm) without any cases of significant brain sagging. The mean follow-up period was 10.1 months (range, 4-19 months). There were no postoperative CSF leaks.


CONCLUSIONS
Rigid structural repair may not be necessary for ASB defect repair after endoscopic endonasal resection of the cribriform plate. Our technique for multilayer cranial base reconstruction appears to be satisfactory in preventing delayed frontal lobe sagging.
Department of Otolaryngology - Head & Neck Surgery, Neurological Institute of New Jersey, University of Medicine and Dentistry of New Jersey - New Jersey Medical School, Newark, New Jersey 07103, USA. jean.anderson.eloy@gmail.com
Jean Anderson
JA
Eloy
Pratik A
PA
Shukla
Osamah J
OJ
Choudhry
Rahul
R
Singh
James K
JK
Liu
D062088:Acellular Dermis; D000293:Adolescent; D000328:Adult; D000368:Aged; D004724:Endoscopy / Q000379:methods*; D005004:Ethmoid Bone / Q000601:surgery*; D005260:Female; D005625:Frontal Lobe / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000637:transplantation; D009300:Nasal Septum / Q000637:transplantation; D009666:Nose; D019651:Plastic Surgery Procedures / Q000379:methods*; D012189:Retrospective Studies; D019291:Skull Base / Q000601:surgery*; D019292:Skull Base Neoplasms / Q000175:diagnosis / Q000601:surgery*; D013524:Surgical Flaps; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult