2026 Poster Presentations
P062: RECONSTRUCTION AND CSF LEAK AFTER ENDOSCOPIC ENDONASAL APPROACH OF CLIVAL CHORDOMAS: A SYSTEMATIC REVIEW AND META-ANALYSIS
Rudolfh Batista Arend, MS1; Pedro Henrique Ieggli, MS1; Bruno Zilli Peroni, MS1; Gabriel Lima Vieira Barbosa, MS2; Lucas Teles da Silva, MS2; Ana Clara Uliana Rezende, MS3; Amanda Delai Lobo, MS4; Natan Lucca Lima, MS5; Alex Roman, Msc, MD6; Martin Batista Coutinho da Silva, MD7; Pierre-Olivier Champagne, MD8; Guilherme Gago, MD7; 1Federal University of Fronteira Sul, Passo Fundo, RS, Brazil; 2Federal University of Ceará, Ceará, Brazil; 3Higher School of Sciences of Santa Casa de Misericórdia of Vitória, Espírito Santo, Brazil; 4Pontifical Catholic University of Paraná, Paraná, Brazil; 5Federal University of Santa Catarina, Santa Catarina, Brazil; 6Institute of Neurosurgery and Spine Surgery (INCC), Passo Fundo, RS, Brazil; 7University of Passo Fundo, Passo Fundo, Brazil; 8Université Laval, Quebec, Canada
Objective: To determine pooled postoperative cerebrospinal fluid (CSF) leak rates after endoscopic endonasal approach (EEA) for clival chordomas, and contextualize associated infectious and CSF-dynamic complications.
Method: We systematically searched PubMed, Embase, Scopus, and Web of Science up to July 2025. We included studies reporting clival chordoma patients treated via an endoscopic endonasal approach with reconstructive details and postoperative CSF leak data; we excluded non-EEA approaches, non-chordoma histologies, non-English/Spanish/Portuguese, series with <5 patients, and secondary evidence (systematic reviews/meta-analyses, conference abstracts, case reports). A single-group meta-analysis of proportions was performed using random-effects with Freeman–Tukey transformation; heterogeneity was summarized with I². Funnel asymmetry was assessed with Egger’s test. The protocol was prospectively registered (PROSPERO: CRD420251155767).
Result: We included 17 observational studies comprising 1123 procedures reporting CSF outcomes. Autologous fat graft was the most frequently used material for skull base reconstruction (reported in 88% of the studies), followed by fascia lata (82%) and vascularized flaps, such as the nasoseptal or middle turbinate flap (71%). Fibrin glue/absorbable gelatin sponge/haemostat was employed in 71% of the studies. A multilayer closure technique was adopted in 88% of the cases. Lumbar drainage was used in 21.4% of patients (n = 420 for this outcome), most often in a prophylactic setting – placed intraoperatively either in all patients or selectively in high-risk cases – and generally maintained for 3 to 5 days. Some authors, however, reserved lumbar drainage for the postoperative initial management of suspected CSF leaks, while others considered external ventricular drainage (EVD) as an alternative under similar circumstances. The pooled CSF leak rate was 11.70% (95%CI 6.82–16.59; I²=62%, p=0.0003). Omitting Schnurman et al., CSF leak rate was 5% (95%CI 3–6; I²=51%). The pooled meningitis rate was 9.81% (95%CI 4.99–14.63; I²=68%, p=0.0009). The pooled hydrocephalus rate was 0.82% (95%CI 0.06–2.15; I²=40%, p=0.14). Omitting Alsayed et al., hydrocephalus rate was 1% (95%CI 0–2; I²=0%). Egger’s test suggested funnel asymmetry for CSF leak and meningitis (intercepts 1.924, 95%CI 1.36–2.49, p=7.36×10?6; and 1.998, 95%CI 1.05–2.95, p=0.0033, respectively), while no asymmetry was detected for hydrocephalus (intercept –1.397, 95%CI –3.29–0.49, p=0.171).
Conclusion: Following EEA for clival chordomas, CSF leak occurs in ~1 in 9 patients and is accompanied by meningitis in ~1 in 10, whereas hydrocephalus is rare. These data underscore the need for aggressive, standardized multilayer/vascularized reconstruction and targeted leak-prevention pathways in high-risk scenarios. Future comparative analyses should clarify the roles of lumbar drains, buttress/gasket-seal adjuncts, and tumor topography (upper vs lower clivus) in mitigating CSF-related morbidity.
Figure 1. PRISMA Flow Diagram
Figure 2. (A) Forest plot, (B) Baujat plot and (C) leave-one-out analysis of cerebrospinal fluid leak
Figure 3. Forest plot of meningitis
Figure 4. (A) Forest plot, (B) Baujat plot and (C) leave-one-out analysis of hydrocephalus
