Graded Reconstruction Strategy Using a Multilayer Technique Without Lumbar Drainage After Endoscopic Endonasal Surgery

Expert Strategies: Skull Base Reconstruction-Global Perspectives, Insights, and Algorithms through a MixedMethods Approach

OBJECTIVE

There is limited consensus on endoscopic skull base surgery (ESBS) reconstruction principles. This study aims to generate comprehensive themes regarding ESBS reconstruction by pooling the experiences of ESBS experts, with comparison to a literature review of current published evidence.

METHODS

Structured qualitative interviews of ESBS experts regarding postoperative management and reconstruction of various defect locations were conducted.

RESULTS

A total of 68 experts comprising 40 academic teams across 13 countries with an average of 18 years of ESBS experience were included. We propose 10 stepwise algorithms for common skull base reconstruction scenarios based on these expert interviews. When available, the nasoseptal flap is used for all high_flow cerebrospinal leak defects. Multilayered reconstruction is favored at all anatomical subsites with increasing number of layers for increasing defect size and complexity. Heterogeneity exists in terms of inlay technique and materials, free grafting versus various pedicled flap options for low-flow defects or in the absence of a nasal septum, nasal packing, tissue sealant, lumbar drain use, and postoperative management. Commonalities and discrepancies between experts were summarized.

CONCLUSION

Skull base reconstruction and post-ESBS management is highly complex with a wide variety of practice patterns and expert strategies. Further research of higher quality evidence is warranted to identify optimal management patterns, though the current work aims to inform surgeons on these controversial areas by drawing from numerous experiences.

Impact of Previous Surgery and/or Radiation Therapy on Endoscopic Reconstruction Outcomes

BACKGROUND AND OBJECTIVES

The impact of prior local therapies, including radiation and surgery, on reconstruction outcomes after endonasal surgery is currently not well known. Reconstruction nuances in the preoperative setting merit further evaluation to avoid potential postoperative complications that can hinder overall tumor management and negatively impact patient outcome. We sought to determine whether prior treatments increase risk of reconstruction-related postoperative morbidity and to evaluate the effectiveness of our current treatment paradigm for skull base reconstruction.

METHODS

A retrospective review of all endonasal surgeries for tumor resection between March 2000 and March 2022 was performed. Patients were grouped based on treatment history. Patient demographics, operative, and postoperative reconstruction-related morbidity data were collected, including cerebrospinal fluid leak, sinonasal morbidity, and infectious complications. Variables significantly associated with postoperative complications in the univariate analysis were included in the multivariate Cox proportional hazards regression model. Complication-free survival curves were generated, and the log-rank test evaluated the relationship between complication-free survival and the different clinical, surgical, and treatment parameters. All statistical analyses were performed with SPSS 26 (IBM Corp) and Graph Pad 9.0 (GraphPad Software).

RESULTS

A total of 418 patients were included. 291 patients had no prior treatments, 49 patients had previously received radiation, and 78 patients had prior surgeries. Of the 49 patients who had prior radiation, 27% underwent reconstruction with tunneled pericranial flaps vs 16% of treatment-naïve patients. On multivariate analysis, prior treatment was not significantly associated with reconstruction-related complications. Negative smoking history, no leak or small intraoperative leak, and use of vascularized flap in reconstruction were protective factors.

CONCLUSION

In patients undergoing endonasal surgery, prior radiation and/or surgery does not appear to significantly increase the risk of immediate or delayed reconstruction complications using our current reconstructive management plan, which incorporates an upfront regional flap for high-risk cases.

Skull base reconstruction using hydroxyapatite and nasoseptal flap versus nasoseptal flap alone: meta-analysis and systematic review

Endoscopic endonasal surgery (EES) is widely employed for interventions in skull base. Despite advancements in surgical techniques, cerebrospinal fluid (CSF) leakage remains a significant concern. The introduction of nasoseptal flap (NSF) dramatically reduced the CSF leakage rates, yet reconstruction techniques continue to vary among institutions and lack standardization. Recently, injectable hydroxyapatite (HA), traditionally used in open skull base reconstruction, has been adapted for use in EES. This study compares the effectiveness of HA and NSF reconstruction with the standard multilayer NSF reconstruction alone. We searched for eligible studies in PubMed, Embase, and Cochrane Library. CSF leakage rates and reconstruction-associated complication rates were thoroughly evaluated. We initially reviewed 3650 records, narrowing down to 13 articles for full-text examination. Of these, 3 retrospective cohort studies met our inclusion criteria, comparing outcomes of HA combined with NSF to NSF alone. The HA plus NSF group tended to exhibit lower rates of CSF leakage compared to the NSF alone group. Similarly, the rate of reconstruction-associated complication was also lower in the HA plus NSF group than in the control group. Skull base reconstruction using HA and NSF can be an effective way to minimize CSF leakage without major complications.

Endoscopic Endonasal Reconstruction of Intraoperative Cerebrospinal Fluid Leak in Different Skull Base Regions: Outcomes, Meningitis, and Risk Factors

OBJECTIVES

Various nonvascularized or vascularized techniques have been adopted in endoscopic endonasal surgery (EES) for repairing intraoperative cerebrospinal fluid (CSF) leaks after tumor resection. Vascularized nasoseptal flaps, free nasoseptal grafts, free turbinate grafts, and fascia lata and mashed muscle are frequently used. Outcomes of those grafts applied in the defects of different regions need to be clarified.

METHODS

The data from a series of 162 patients with skull base tumor who underwent EES that had intraoperative CSF leak between Jan 2012 and Jan 2021 were retrospectively analyzed. The regions included anterior skull base, sellar region, clivus and infratemporal fossa. Repair failure rate (RFR), meningitis rate, and associated risk factors were assessed.

RESULTS

In total, 172 reconstructions were performed in 162 patients for the 4 sites of the skull base. There were 7 cases (4.3%) that had postoperative CSF leaks, which required second repair. The RFR for anterior skull base, sellar region, clivus, and infratemporal fossawas 2.6%, 2.2%, 16.7%, and 0%, respectively. The clivus defect was an independent risk factor for repair failure (P < 0.01). The postoperative meningitis rate was 5.6%. Repair failure was an independent risk factor for meningitis (P < 0.01).

CONCLUSIONS

Vascularized nasoseptal flap, free nasoseptal graft, free turbinate graft, and fascia lata and mashed muscle are reliable autologous materials for repairing the dural defects in different regions during EES. Clivus reconstruction remains a great challenge, which had a higher RFR and meningitis rate. Repair failure is significantly associated with postoperative meningitis.

Safety and efficacy of hydroset cranioplasty as an adjunct to gasket-seal and nasoseptal flap closure of the skull base. A case-controlled study

BACKGROUND

Cerebrospinal fluid leak after endoscopic skull base surgery remains a significant complication. Several investigators have suggested Hydroset cranioplasty to reduce leak rates. We investigated our early experience with Hydroset and compared the rate of nasal complications and CSF leak rates with case-controlled historic controls.

METHODS

We queried a prospective database of patients undergoing first time endoscopic, endonasal resection of suprasellar meningiomas and craniopharyngiomas from 2015 to 2023. We compared cases closed with a gasket seal, Hydroset, and a nasoseptal flap with those closed with only a gasket seal and nasoseptal flap. Demographics, technical considerations and postoperative outcomes (SNOT-22) were compared.

RESULTS

Seventy patients met inclusion criteria, twenty patients in the Hydroset group (meningioma n = 12; craniopharyngioma n = 8) and 50 control patients (meningioma n = 25; craniopharyngioma n = 25). CSF diversion was used in fewer Hydroset patients (75%, 15/20) compared with control group (94%, 47/50; p = 0.02). CSF leak was less frequent in the Hydroset than the control group (5% versus 12%, p = 0.38). One Hydroset patient required delayed nasal debridement. SNOT-22 responses demonstrated no significant difference in sinonasal complaints between groups (Hydroset average SNOT-22 score 22.45, control average SNOT-22 score 25.90; p = 0.58).

CONCLUSIONS

We demonstrate that hydroxyapatite reconstruction leads to improved CSF leak control above that provided by the gasket-seal and nasoseptal flap, without significant associated morbidity as long as the cement is fully covered with vascularized tissue.

Efficacy of hydroxyapatite-based skull base reconstruction for intraoperative high-flow cerebrospinal fluid leakage performed by less-experienced surgeons

Cerebrospinal fluid (CSF) leakage after endoscopic skull base surgery remains a challenge despite multilayer reconstruction including nasoseptal flap (NSF) has become a standard technique. Injectable hydroxyapatite (HXA) has shown promising results to prevent CSF leakage. This study aimed to validate the efficacy of HXA-based skull base reconstruction performed by less-experienced neurosurgeons who had short-term clinical experiences as independent surgeons. Between March 2018 and November 2022, 41 patients who experienced intraoperative high-flow CSF leakage following endoscopic endonasal surgery at two independent tertiary institutions were enrolled. Skull base reconstruction was performed using conventional multilayer techniques combined with or without HXA. The primary outcome was postoperative CSF leakage. The surgical steps and nuances were described in detail. The most common pathology was craniopharyngioma. Injectable HXA was used in 22 patients (HXA group) and conventional techniques were performed in 19 patients (control group). The HXA group achieved a significantly lower incidence of postoperative CSF leakage than the control group (0% vs. 26.3%, p = 0.016). No HXA-related complications were observed. The use of injectable HXA in skull base reconstruction was highly effective and safe. This technique and its favorable results might be readily reproduced by less-experienced neurosurgeons.

Combined surgical repair and venous sinus stenting for patients with skull base encephaloceles secondary to dural venous sinus stenosis

BACKGROUND

Chronically elevated intracranial pressure (ICP) seen in idiopathic intracranial hypertension (IIH) can cause the development of skull base encephaloceles and cerebrospinal fluid (CSF) leaks. Surgical repair and ventriculoperitoneal shunt (VPS) placement are mainstays of treatment. Venous sinus stenting (VSS) is a newly accepted treatment modality. The goal of this study was thus to determine if VSS can be used to treat symptoms and prevent recurrence after surgical encephalocele repair.

METHODS

Retrospective chart review of patients that had surgical repair of encephaloceles followed by VSS for symptomatic stenosis with elevated pressure gradient.

RESULTS

A total of 13 patients underwent a combined encephalocele repair and VSS. Seventy-two percent were female; 46% had headaches, 69% pulsatile tinnitus, and 92% CSF rhinorrhea or otorrhea. One had seizures. Mean lumbar opening pressure was 23.3 ± 2.6 cm H2O; the average sagittal-to-jugular pressure gradient was 12.7 ± 1.8 cmH2O and was elevated in all patients. Four patients had middle fossa craniotomy for repair of tegmen defect (one bilateral); one had a retrosigmoid craniotomy for repair of a sigmoid plate defect. Eight had an endoscopic endonasal repair for sphenoid or cribriform plate encephalocele. There were no VSS procedural complications or complications associated with dual antiplatelet therapy. One patient had meningitis after endoscopic repair that was treated with antibiotics. One patient had recurrence of both CSF leak and venous stenosis adjacent to the stent requiring repeat repair and VSS. There was no further recurrence.

CONCLUSION

In patients with dural sinus stenosis and encephaloceles requiring repair, VSS can be performed safely within weeks of surgery for relief of symptoms, resolution of underlying pathology, and prevention of CSF leak recurrence.

Antibiotics Prophylaxis for Endoscopic Endonasal Approach for Skull Base Tumor Surgery: A Meta-Analysis

BACKGROUND

The regimen of prophylactic antibiotic for endoscopic endonasal skull base surgery (EE-SBS) varies considerably depending on surgeons and their institutes. The purpose of the present meta-analysis is to assess the effect of antibiotic regimens on EE-SBS surgery for anterior skull base tumor.

METHODS

The PubMed, Embase, Web of Science, and Cochrane clinical trial databases were systematically searched through October 15, 2022.

RESULTS

The 20 included studies were all retrospective. The studies included a total of 10,735 patients who underwent EE-SBS for skull base tumor. The proportion of patients with postoperative intracranial infection across all 20 studies was 0.9% (95% confidence interval [CI] 0.5%-1.3%). The proportion of postoperative intracranial infection in the multiple antibiotics group did not show statistically significant difference to that of the single antibiotic agent group (proportion: 0.6%, 95% CI 0%-1.4% vs. proportion: 1%, 95% CI 0.6%-1.5%, respectively, P = 0.39). The ultra-short duration maintenance group showed lower incidence of postoperative intracranial infection, although it did not reach statistical significance (ultra-short group: 0.7%, 95% CI 0.5%-0.9%; short duration: 1.8%, 95% CI 0.5%-3%; and long duration: 1%, 95% CI 0.2%-1.9%, P = 0.22) The combination of the multiple antibiotics group did not show meaningful low incidence of postoperative intracranial infection (antibiotics combination group: 0.6%, 95% CI 0%-1.4%; cefazolin single group: 0.8%, 95% CI 0%-1.6%; and single antibiotics other than cefazolin: 1.2%, 95% CI 0.7%-1.7%, P = 0.22).

CONCLUSIONS

Multiple antibiotics did not show superiority compared with single antibiotic agent. Also, long maintenance duration of antibiotics did not reduce the incidence of postoperative intracranial infection.

Closure strategy for endoscopic pituitary surgery: Experience from 3015 patients

Introduction

Effective strategies are required to ensure optimal management of the crucial closure step in endoscopic pituitary surgery. Many surgical techniques have been reported but no significant consensus has been defined.

Methods

Between January 2006 and March 2022, 3015 adult patients with pituitary adenomas were operated on by a single expert neurosurgical team, using a mononostril endoscopic endonasal approach. Based of preoperative risk factors of and operative findings, a detailed closure strategy was used. Body mass index >40, sellar floor lysis, number of surgeries>2, large skull base destruction, prior radiotherapy were considered as preoperative risk factors for closure failure. All patients treated with an expanded endonasal approach were excluded.

Results

Patients were mostly women (F/M ratio: 1.4) with a median age of 50 (range: 18 -89). Intraoperative CSF leak requiring specific surgical management was observed in 319/3015 (10.6%) of patients. If intraoperative leak occurred, patients with predictive risk factors were managed using a Foley balloon catheter in case of sellar floor lysis or BMI>40 and a multilayer repair strategy with a vascularized nasoseptal flap in other cases. Postoperative CSF leak occurred in 29/3015 (1%) of patients, while meningitis occurred in 24/3015 (0.8%) of patients. In patients with intraoperative leak, closure management failed in 11/319 (3.4%) of cases.

Conclusion

Based on our significant 16-year experience, our surgical management is reliable and easy to follow. With a planned and stepwise strategy, the closure step can be optimized and tailored to each patient with a very low failure rate.

Extended endoscopic endonasal approach for resecting anterior intrinsic third ventricular craniopharyngioma

Background

The surgical treatment of the extended endoscopic endonasal approach (EEEA) is a safe and effective treatment for suprasellar craniopharyngiomas. However, due to damage to the hypothalamus and third ventricle floor (TVF), EEEA is generally regarded as unsuitable in treating intrinsic third ventricle craniopharyngioma (ITVC) that is entirely within the third ventricle. Until now, there have been only a small number of reports using EEEA to treat TVC via a supra-infrachiasmatic approach. Given that the translamina terminalis (TLT) corridor was used in the transcranial subfrontal approach, EEEA via a suprachiasmatic approach may be feasible and practical to treat ITVC. In the current study, we accumulated experience applying the suprachiasmatic translamina terminalis (STLT) corridor for anterior treatment of ITVC.

Methods

From March 2016 to December 2020, 14 patients with ITVC in our center were analyzed retrospectively. All patients underwent surgery by EEEA via an STLT corridor. The multilayer reconstruction technique was adopted to achieve skull base reconstruction. Data concerning the patient’s tumor resection, vision, hypophyseal hormone, and complications were collected.

Results

Gross-total resection was achieved in 13 (92.8%) of14 patients, with achievement of near-total (90%) resection in the remaining 1 patient. Nine cases (64.3%) were papillary craniopharyngiomas, and the other 5 cases were adamantinomatous subtypes. Postoperatively, 3 patients with pituitary insufficiency received hormone replacement therapy. No permanent diabetes insipidus or hypothalamic obesity was found. All pairs showed significant improvement or stability in vision except 1 patient who encountered visual deterioration. No other neurological deficit occurred postoperatively. Observation results for the exudation of nasal tissue and the length of hospitalization were satisfactory. After a mean follow-up period of 26.2 months, tumor recurrence was not observed.

Conclusion

TLT is a minimally invasive corridor used in EEEA for treating anterior ITVC without increasing risks of visual and hormonal deficits. The multilayered reconstruction technique we used is a safe and effective method for achieving watertight closure and avoiding cerebrospinal fluid leaks and infection. The endonasal approach via STLT provides a new, safe and efficacious operative strategy that should be considered a surgical alternative in treating ITVC.

Clinical Impact of Hydroxyapatite on the Outcome of Skull Base Reconstruction for Intraoperative High-Flow CSF Leak: A Propensity Score Matching Analysis

Background

Despite recent advances in skull base reconstructive techniques, including the multilayer technique during the last decade, complete reconstruction of grade 3 intraoperative high-flow cerebrospinal fluid (CSF) leak remains challenging. This study was designed to investigate the role of injectable hydroxyapatite (HXA) used in the multilayer technique on the clinical outcome of skull base reconstruction for intraoperative high-flow CSF leak.

Materials and Methods

This study enrolled 187 patients who experienced intraoperative high-flow CSF leak after endoscopic endonasal surgery for anterior skull base or suprasellar pathologies between January 2014 and July 2021. All skull base defects were reconstructed using the conventional multilayer technique including a vascularized naso-septal flap (NSF, n = 141) and the combined use of HXA with the conventional multilayer technique (HXA group, n = 46). We retrospectively evaluated the efficacy of the HXA group by 1:2 propensity score matching analysis.

Results

Overall, 17 of 187 patients (9.1%) showed postoperative CSF leaks, resulting in second reconstruction surgery. There were no statistical differences in patient age, sex, body mass index, tumor location, tumor type, and degree of resection, except for the follow-up period between the two groups. The HXA group showed a significantly lower incidence of postoperative CSF leak than the control group (0% vs. 12.1%, p < 0.05). Postoperative lumbar drain (LD) was performed in 8.7% of the HXA group compared to 46.1% of the control group (p < 0.01). CSF leak-related infection rates showed a decreasing tendency in the HXA group compared to the control group (0 vs. 7.1%, p = 0.06). A total of 46 patients in the HXA group were well matched with the control group (92 patients) at a 1:2 ratio. In the propensity score-matched control group, there were higher rates of postoperative CSF leaks than in the HXA group.

Conclusion

The use of HXA combined with the conventional multilayer technique completely reduced postoperative CSF leaks in this study. This technique resulted in reduced CSF leakage, even without postoperative LD, and decreased infection rates. Further randomized comparative studies are required to confirm our findings.