Pedicled Nasoseptal Flap After Endoscopic Endonasal Resection of Skull Base Tumors: A Comparative Meta-Analysis with Other Modalities of Reconstruction

Abstract

Objectives

Endoscopic endonasal surgery for skull base tumors has advanced significantly, but postoperative cerebrospinal fluid (CSF) leak remains a significant concern. Introducing the vascularized pedicled nasoseptal flap (PNSF) has markedly reduced CSF leak rates, though outcomes remain variable across different studies. This systematic review and meta-analysis aimed to compare the efficacy of vascularized versus nonvascularized reconstruction techniques in these procedures.

Design

Three databases (PubMed, Cochrane, and Embase) were systematically searched to identify studies comparing CSF leak rates between PNSF and nonvascularized techniques for reconstruction after endoscopic endonasal skull base surgeries. It was designed according to the preferred reporting items for systematic reviews and meta-analyses reporting guidelines. Statistical analysis was performed using Review Manager, with heterogeneity evaluated via the I ² statistic.

Results

After thorough selection, twenty articles were selected, and a total of 4,088 patients were included, of whom 1,851 were assigned to the nasoseptal flap group, and 2,237 were assigned to the no-flap group. The postoperative CSF leak ratio was significantly lower in the group that underwent reconstruction with PNSF compared with all the other grouped methods, respectively, 3.4 and 5.6% (odds ratio [OR]: 0.48; 95% confidence interval [CI]: 0.34–0.66; p < 0.00001; I ² = 54%).

Conclusion

Our results suggest that using the PNSF is associated with a lower incidence of postoperative CSF leak than other reconstruction techniques in endoscopic skull base surgeries and may be used for patients at risk of this complication.

Keywords

skull base tumors - endoscopic endonasal resection - nasoseptal flap - skull base reconstruction

Contributors' Statement

A.M.L.F. and R.A.C.C. were responsible for the conception and design of the study. Material preparation, data collection, and analysis were performed by A.M.L.F., M.N.F.F., and O.A.P.M.T. The first draft of the manuscript was written by A.M.L.F., R.A.C.C., M.N.F.F., and O.A.P.M.T., and all authors provided comments on previous versions of the manuscript. All authors read and approved the final manuscript.

Publication History

Received: 02 February 2025

Accepted: 23 June 2025

Article published online:
10 July 2025

• References

• 1 Tadokoro K, Domack A, Germanwala AV. et al. Open and endoscopic skull base approaches. Curr Otorhinolaryngol Rep 2020; 8: 136-146
• 2 Hannan CJ, Almhanedi H, Al-Mahfoudh R, Bhojak M, Looby S, Javadpour M. Predicting post-operative cerebrospinal fluid (CSF) leak following endoscopic transnasal pituitary and anterior skull base surgery: a multivariate analysis. Acta Neurochir (Wien) 2020; 162 (06) 1309-1315
• 3 Hadad G, Bassagasteguy L, Carrau RL. et al. A novel reconstructive technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope 2006; 116 (10) 1882-1886
• 4 Di Perna G, Penner F, Cofano F. et al. Skull base reconstruction: a question of flow? A critical analysis of 521 endoscopic endonasal surgeries. PLoS One 2021; 16 (03) e0245119
• 5 Esposito F, Dusick JR, Fatemi N, Kelly DF. Graded repair of cranial base defects and cerebrospinal fluid leaks in transsphenoidal surgery. Oper Neurosurg (Hagerstown) 2007; 60 (4, suppl 2): 295-303 , discussion 303–304
• 6 Luginbuhl AJ, Campbell PG, Evans J, Rosen M. Endoscopic repair of high-flow cranial base defects using a bilayer button. Laryngoscope 2010; 120 (05) 876-880
• 7 Garcia-Navarro V, Anand VK, Schwartz TH. Gasket seal closure for extended endonasal endoscopic skull base surgery: efficacy in a large case series. World Neurosurg 2013; 80 (05) 563-568
• 8 Hara T, Akutsu H, Yamamoto T. et al. Cranial base repair using suturing technique combined with a mucosal flap for cerebrospinal fluid leakage during endoscopic endonasal surgery. World Neurosurg 2015; 84 (06) 1887-1893
• 9 Ishikawa T, Takeuchi K, Nagata Y. et al. Three types of dural suturing for closure of CSF leak after endoscopic transsphenoidal surgery. J Neurosurg 2018; 131 (05) 1625-1631
• 10 Kassam AB, Thomas A, Carrau RL. et al. Endoscopic reconstruction of the cranial base using a pedicled nasoseptal flap. Neurosurgery 2008; 63 (Suppl. 01) ONS44-ONS52 , discussion ONS52–ONS53
• 11 Zanation AM, Carrau RL, Snyderman CH. et al. Nasoseptal flap reconstruction of high flow intraoperative cerebral spinal fluid leaks during endoscopic skull base surgery. Am J Rhinol Allergy 2009; 23 (05) 518-521
• 12 Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hofmann TC, Mulrow CD. The PRISMA et al. statement: an updated guideline for reporting systematic reviews. BMJ 2020; 2021: 372
• 13 Sterne JAC, Savović J, Page MJ. et al. RoB 2: a revised tool for assessing risk of bias in randomised trials. BMJ 2019; 366: l4898
• 14 Sterne JA, Hernán MA, Reeves BC. et al. ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions. BMJ 2016; 355: i4919
• 15 Tam S, Duggal N, Rotenberg BW. Olfactory outcomes following endoscopic pituitary surgery with or without septal flap reconstruction: a randomized controlled trial. Int Forum Allergy Rhinol 2013; 3 (01) 62-65
• 16 Jakimovski D, Bonci G, Attia M. et al. Incidence and significance of intraoperative cerebrospinal fluid leak in endoscopic pituitary surgery using intrathecal fluorescein. World Neurosurg 2014; 82 (3–4): e513-e523
• 17 Tosaka M, Prevedello DM, Yamaguchi R. et al. Single-layer fascia patchwork closure for the extended endoscopic transsphenoidal transtuberculum transplanum approach: deep suturing technique and preliminary results. World Neurosurg 2021; 155: e271-e284
• 18 Younus I, Gerges MM, Uribe-Cardenas R. et al. How long is the tail end of the learning curve? Results from 1000 consecutive endoscopic endonasal skull base cases following the initial 200 cases. J Neurosurg 2020; 134 (03) 750-760
• 19 Eide JG, Salmon MK, Kshirsagar RS. et al. Reconstruction with mucosal graft reduces recurrence after endoscopic surgery of Rathke cleft cyst. World Neurosurg 2022; 167: e664-e669
• 20 Jeon C, Hong SD, Seol HJ. et al. Reconstructive outcome of intraoperative cerebrospinal fluid leak after endoscopic endonasal surgery for tumors involving skull base. J Clin Neurosci 2017; 45: 227-231
• 21 Kessler RA, Garzon-Muvdi T, Kim E, Ramanathan M, Lim M. Utilization of the nasoseptal flap for repair of cerebrospinal fluid leak after endoscopic endonasal approach for resection of pituitary tumors. Brain Tumor Res Treat 2019; 7 (01) 10-15
• 22 Koutourousiou M, Gardner PA, Fernandez-Miranda JC, Tyler-Kabara EC, Wang EW, Snyderman CH. Endoscopic endonasal surgery for craniopharyngiomas: surgical outcome in 64 patients. J Neurosurg 2013; 119 (05) 1194-1207
• 23 Kuan EC, Yoo F, Patel PB, Su BM, Bergsneider M, Wang MB. An algorithm for sellar reconstruction following the endoscopic endonasal approach: a review of 300 consecutive cases. J Neurol Surg B Skull Base 2018; 79 (02) 177-183
• 24 Li B, Zhao S, Fang Q. et al. Risk factors and management associated with postoperative cerebrospinal fluid leak after endoscopic endonasal surgery for pituitary adenoma. Front Surg 2022; 9: 973834
• 25 Mascarenhas L, Moshel YA, Bayad F. et al. The transplanum transtuberculum approaches for suprasellar and sellar-suprasellar lesions: avoidance of cerebrospinal fluid leak and lessons learned. World Neurosurg 2014; 82 (1-2): 186-195
• 26 McCoul ED, Anand VK, Singh A, Nyquist GG, Schaberg MR, Schwartz TH. Long-term effectiveness of a reconstructive protocol using the nasoseptal flap after endoscopic skull base surgery. World Neurosurg 2014; 81 (01) 136-143
• 27 McDowell MM, Chiang M, Abou-Al-Shaar H. et al. Applications of endoscopic endonasal surgery in early childhood: a case series. Pediatr Neurosurg 2021; 56 (06) 519-528
• 28 Paluzzi A, Fernandez-Miranda JC, Tonya Stefko S, Challinor S, Snyderman CH, Gardner PA. Endoscopic endonasal approach for pituitary adenomas: a series of 555 patients. Pituitary 2014; 17 (04) 307-319
• 29 Pérez-López C, Palpan AJ, Zamarrón Á. et al. Free mucosal graft for reconstruction after nonfunctional pituitary adenoma surgery. Asian J Neurosurg 2020; 15 (04) 946-951
• 30 Horiguchi K, Murai H, Hasegawa Y, Hanazawa T, Yamakami I, Saeki N. Endoscopic endonasal skull base reconstruction using a nasal septal flap: surgical results and comparison with previous reconstructions. Neurosurg Rev 2010; 33 (02) 235-241 , discussion 241
• 31 Zhao W, Yang G, Li R. et al. Effects of cruciate embedding fascia-bone flap technique on grade II-III cerebral spinal fluid leak in endoscopic endonasal surgery. BMC Surg 2022; 22 (01) 288
• 32 Rotman LE, Kicielinski KP, Broadwater DR. et al. Predictors of nasoseptal flap use after endoscopic transsphenoidal pituitary mass resection. World Neurosurg 2018; 124: e356-e364
• 33 Zhang C, Yang Z, Liu P. Strategy of skull base reconstruction after endoscopic transnasal pituitary adenoma resection. Front Surg 2023; 10: 1130660
• 34 Majovsky M, Astl J, Kovar D, Masopust V, Benes V, Netuka D. Olfactory function in patients after transsphenoidal surgery for pituitary adenomas-a short review. Neurosurg Rev 2019; 42 (02) 395-401
• 35 Castle-Kirszbaum M, Wang YY, King J. et al. Patient wellbeing and quality of life after nasoseptal flap closure for endoscopic skull base reconstruction. J Clin Neurosci 2020; 74: 87-92