Evolution of the graded repair of CSF leaks and skull base defects in endonasal endoscopic tumor surgery: trends in repair failure and meningitis rates in 509 patients

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.

The impact of obesity on rates of post-operative CSF leak following endoscopic skull base surgery: results from a prospective international multi-centre cohort study

Aims

Post-operative CSF leak is the major source of morbidity following transsphenoidal approaches (TSA) and expanded endonasal approaches (EEA) to lesions of the sella turcica and the ventral skull base. There are conflicting reports in the literature as to whether obesity (BMI ≥30) is a risk factor for this complication. We aimed to evaluate data collected as part of prospective multi-centre cohort study to address this question.

Methods

The CRANIAL (CSF Rhinorrhoea After Endonasal Intervention to the Skull Base) study database was reviewed and patients were divided into obese and non-obese cohorts. Data on patient demographics, underlying pathology, intra-operative findings and skull base repair techniques were analysed.

Results

TSA were performed on 726 patients, of whom 210 were obese and 516 were non-obese. The rate of post-operative CSF leak in the obese cohort was 11/210 (5%), compared to 17/516 (3%) in the non-obese cohort, which was not statistically significant (χ2 = 1.520, p=0.217). EEA were performed on 140 patients, of whom 28 were obese and 112 were non-obese. The rate of post-operative CSF leak in the obese cohort was 2/28 (7%), which was identical to the rate observed in the non-obese cohort 8/112 (7%) Fisher's Exact Test, p=1.000). These results persisted following adjustment for inter-institutional variation and baseline risk of post-operative CSF leak.

Conclusion

CSF leak rates following TSA and EEA, in association with modern skull base repair techniques, were found to be low in both obese and non-obese patients. However, due to the low rate of post-operative CSF leak, we were unable to fully exclude a small contributory effect of obesity to the risk of this complication.

Free temporalis muscle fascia graft in dural reconstruction following surgical resection of intermediate and malignant skull base tumors: A 10-year experience from a single center

BACKGROUND

Data from patients with post-ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base tumors were retrospectively analyzed.

METHODS

The primary predictor and outcome variables were the reconstructive methods for dural repair and postoperative cerebrospinal fluid (CSF) leakage rate, respectively.

RESULTS

Eighty patients were included, and 94 postoperative dural reconstructions were performed using FTFG. The postoperative CSF leakage rate was 3.19%. The postoperative CSF leakage rates did not significantly differ between open and endonasal endoscopic surgeries (1.92% vs. 4.88%; p > 0.05). In cases completed using the endonasal endoscopic approach, the postoperative CSF leakage rate was significantly associated with the intraoperative CSF leak flow (p < 0.05).

CONCLUSIONS

Post-ablative dural defect reconstruction using FTFG resulted in low postoperative CSF leakage and complication rates comparable to those of free fascia lata graft from available literature.

A Comprehensive Analysis of Tobacco Smoking History as a Risk for Outcomes after Endoscopic Transsphenoidal Resection of Pituitary Adenoma

Objectives  This study seeks to comprehensively analyze the impact of smoking history on outcomes after endoscopic transsphenoidal hypophysectomy (TSH) for pituitary adenoma. Design  This was a retrospective study. Setting  This study was done at the tertiary care center. Participants  Three hundred and ninety-eight adult patients undergoing TSH for a pituitary adenoma. Main Outcome Measures  Clinical and tumor characteristics and operative factors were collected. Patients were categorized as never, former, or active smokers, and the pack-years of smoking history was collected. Years since cessation of smoking was obtained for former smokers. Specific outcomes included postoperative cerebrospinal fluid (CSF) leak, length of hospitalization, 30-day return to the operating room, and 30-day readmission. Smoking history details were comprehensively analyzed for association with outcomes. Results  Any history of smoking tobacco was associated with return to the operating room (odds ratio [OR] = 2.67, 95% confidence interval [CI]: 1.05-6.76, p  = 0.039), which was for persistent CSF leak in 58.3%. Among patients with postoperative CSF leak, any history of smoking was associated with need for return to the operating room to repair the CSF leak (OR = 5.25, 95% CI: 1.07-25.79, p  = 0.041). Pack-years of smoking was positively associated with a return to the operating room (OR = 1.03, 95% CI: 1.01-1.06, p  = 0.048). In all multivariable models, all negative outcomes were significantly associated with the covariate: occurrence of intraoperative CSF leak. Conclusion  This is the first study to show smoking may have a negative impact on healing of CSF leak repairs after TSH, requiring a return to the operating room. This effect appears to be dose dependent on the smoking history. Secondarily, intraoperative CSF leak as covariate in multivariable models was significantly associated with all negative outcomes.

Systematic review of errors on beta-2 transferrin gel electrophoresis testing of rhinorrhea and otorrhea

BACKGROUND

Beta-2 transferrin (B2-Tf) gel electrophoresis (GE) is the preferred non-invasive diagnostic modality for confirming cerebrospinal fluid (CSF) in body fluids. While B2-Tf GE testing is highly sensitive and specific for CSF, false-positive (FP) and false-negative (FN) results can lead to diagnostic and therapeutic dilemmas. Several series have demonstrated potential causes of false B2-Tf GE results, but few studies have reported reasons for these errors. The purpose of this systematic review was to describe sources of B2-Tf GE errors.

METHODS

A systematic review was performed by searching OVID, EMBASE, and Web of Science databases for B2-Tf GE studies. After applying exclusion criteria, original research studies directly addressing erroneous B2-Tf GE results underwent qualitative analysis.

RESULTS

Of the 243 abstracts screened, 71 underwent full-text review and 18 studies reporting B2-Tf GE errors were included for analysis. There were 15 potential FPs, 12 actual FPs, 12 potential FNs, 19 actual FNs, and 14 indeterminate results. There were also 246 potentially indeterminate results from in vitro studies. Reasons for B2-Tf GE errors included serum transferrin alterations (n = 17; all potential), infection related (n = 13; 9 potential), orbital or salivary contamination (n = 2; 1 potential), and collection related (n = 255; 246 potential). There were 31 false or indeterminate results with unspecified reasons. There were no reported errors due to laboratory processing.

CONCLUSIONS

Multiple potential or actual reasons for false or indeterminate results have been reported for B2-Tf GE testing of rhinorrhea and otorrhea. Future studies should explore reasons for B2-Tf testing errors and how these may affect clinical decision making.

The Transorbital Approach: A Comprehensive Review of Targets, Surgical Techniques, and Multiportal Variants

The transorbital approach (TOA) is gaining popularity in skull base surgery scenarios. This approach represents a valuable surgical corridor to access various compartments and safely address several intracranial pathologies, both intradurally and extradurally, including tumors of the olfactory groove in the anterior cranial fossa (ACF), cavernous sinus in the middle cranial fossa (MCF), and the cerebellopontine angle in the posterior cranial fossa (PCF). The TOA exists in many variants, both from the point of view of invasiveness and from that of the entry point to the orbit, corresponding to the four orbital quadrants: the superior eyelid crease (SLC), the precaruncular (PC), the lateral retrocanthal (LRC), and the preseptal lower eyelid (PS). Moreover, multiportal variants, consisting of the combination of the transorbital approach with others, exist and are relevant to reach peculiar surgical territories. The significance of the TOA in neurosurgery, coupled with the dearth of thorough studies assessing its various applications and adaptations, underscores the necessity for this research. This extensive review delineates the multitude of target lesions reachable through the transorbital route, categorizing them based on surgical complexity. Furthermore, it provides an overview of the different transorbital variations, both standalone and in conjunction with other techniques. By offering a comprehensive understanding, this study aims to enhance awareness and knowledge regarding the current utility of the transorbital approach in neurosurgery. Additionally, it aims to steer future investigations toward deeper exploration, refinement, and exploration of additional perspectives concerning this surgical method.

An experience in treatment of neurologically silent clival chordoma mimicking a nasopharyngeal tumor

Cranial chordoma is a rare neoplasm that is challenging to both diagnose and manage. We present our experience in treating a case of clival chordoma mimicking a nasopharyngeal mass without any signs of cranial deficits or intracranial insult. Management was comprised of endoscopic transnasal debulking surgery followed by radiotherapy. However, we failed to achieve an oncologic outcome due to the development of lethal central nervous system and respiratory infections 1 month after the surgery.

Profiles of central nervous system surgical site infections in endoscopic transnasal surgery exposing the intradural space

OBJECTIVE

Despite its efficacy and minimal invasiveness, the clean-contaminated nature of endoscopic transnasal surgery (ETS) may be susceptible to central nervous system surgical site infections (CNS-SSIs), especially when involving intradural exposure. However, the profiles of ETS-associated CNS-SSIs are not fully elucidated.

METHODS

The institutional ETS cases performed between May 2017 and March 2023 were retrospectively analysed. The incidences of CNS-SSIs were calculated, and their risk factors examined.

RESULTS

The incidence of CNS-SSIs was 2.3% (7/305) in the entire cohort and 5.0% (7/140) in ETSs with intradural exposure. All the CNS-SSIs were meningitis and developed following ETS with intradural exposure. The incidences were 0%, 5.6% and 5.8% in ETSs with Esposito grade 1, 2 and 3 intraoperative cerebrospinal fluid leakage, respectively. Among the pre- and intra-operative factors, body mass index (unit odds ratio (OR), 0.62; 95% confidence interval (CI), 0.44-0.89; P<0.01), serum albumin (unit OR, 0.03; 95% CI, 0.0007-0.92; P=0.02), and American Society of Anesthesiologists physical status score (unit OR, 20.7; 95% CI, 1.65-259; P<0.01) were significantly associated with CNS-SSIs. Moreover, postoperative cerebrospinal fluid leakage was also significantly associated with CNS-SSIs (OR, 18.4; 95% CI, 3.55-95.0; P<0.01).

CONCLUSIONS

The incidence of ETS-associated CNS-SSIs is acceptably low. Intradural exposure was a prerequisite for CNS-SSIs. Malnutrition and poor comorbidity status should be recognized as important risks for CNS-SSIs in ETS.

CSF leak after pediatric endoscopic endonasal expanded approaches: a series review

PURPOSE

Endoscopic endonasal approaches in the pediatric population pose specific challenges. Management of postoperative cerebrospinal fluid [CSF] leak is probably the major concern. The purpose of the present investigation is to describe and analyze the incidence of postoperative CSF leaks in our pediatric series of endoscopic endonasal approaches.

METHODS

This is a retrospective analysis, case review of our institutional series. Descriptive statistical parameters and bivariate correlations are analyzed.

RESULTS

Twenty-one patients have been operated through endoscopic approaches in our series. Four patients showed a postoperative CSF leak needing a revision surgery; these cases are described in further detail. Approaches expanded beyond the sellar area and non-sellar pneumatization of the sphenoid sinus were significantly associated with a higher risk of postoperative CSF leak.

CONCLUSIONS

CSF leak incidence after endoscopic endonasal approaches is higher in pediatric patients than in adult series. Anatomic and pathologic factors add complexity to these approaches in children. Multilayer closure is advisable to prevent and treat this complication.

Application of a Novel Versatile Mini Posterior Nasoseptal Graft in Endoscopic Transsphenoidal Pituitary Adenoma Surgery

BACKGROUND

Skull base reconstruction is a key technique in patients undergoing endoscopic transnasal skull base surgery. Although a pedicled nasoseptal flap (PNSF) is often used to repair large skull base defects with high-flow cerebrospinal fluid leakage, bone exposure of the donor site of the PNSF can result in long-term crusting.

OBJECTIVE

To design a novel and versatile mini posterior nasoseptal graft for the reconstruction of defects in the sellar floor or PNSF or pedicled nasoseptal rescue flap (PNSRF) donor site in patients undergoing pituitary adenoma surgery.

METHODS

Patients who underwent pituitary adenoma removal through an endoscopic endonasal approach and repair of a sellar defect or PNSF/PNSRF donor site using the mini posterior nasoseptal graft technique from January 2019 to January 2020 were retrospectively evaluated. Pituitary adenomas were removed using a binostril 4-hand technique through a transnasal transsphenoidal transsellar approach or an expanded transsellar approach.

RESULTS

Mini posterior nasoseptal grafts were successfully used in 70 patients who underwent pituitary adenoma removal through an endoscopic transsphenoidal sellar approach. Mini posterior nasoseptal grafts repaired sellar defects in 40 patients and donor site defects of the contralateral PNSF/PNSRF in 30 patients. None of these patients experienced cerebrospinal fluid leakage or major complications.

CONCLUSIONS

A mini posterior nasoseptal graft is a safe and effective technique for repairing sellar defects after endoscopic transnasal pituitary adenoma surgery. This technique can also be used to repair defects in PNSF/PNSRF donor sites.

"In situ bone flap" combined with vascular pedicled mucous flap to reconstruction of skull base defect

BACKGROUND

At present, neuroendoscopy technology has made rapid development, and great progress has been made in the operation of lesions in the saddle area of the skull base. However, the complications of cerebrospinal fluid and intracranial infection after the operation are still important and life-threatening complications, which may lead to poor prognosis.

AIM

To investigate the method of in situ bone flap combined with nasal septum mucosal flap for reconstruction of enlarged skull base defect by endonasal sphenoidal approach and to discuss its application effect.

METHODS

Clinical data of 24 patients undergoing transnasal sphenoidal endoscopic approach in the Department of Neurosurgery, Affiliated 2 Hospital of Nantong University from January 2019 to December 2022 were retrospectively analyzed. All patients underwent multi-layer reconstruction of skull base using in situ bone flap combined with nasal septum mucosa flap. The incidence of intraoperative and postoperative cerebrospinal fluid leakage and intracranial infection were analyzed, and the application effect and technical key points of in situ bone flap combined with nasal septum mucosa flap for skull base bone reconstruction were analyzed.

RESULTS

There were 5 cases of high flow cerebrospinal fluid (CSF) leakage and 7 cases of low flow CSF leakage. Postoperative cerebrospinal fluid leakage occurred in 2 patients (8.3%) and intracranial infection in 2 patients (8.3%), which were cured after strict bed rest, continuous drainage of lumbar cistern combined with antibiotic treatment, and no secondary surgical repair was required. The patients were followed up for 8 to 36 months after the operation, and no delayed cerebrospinal fluid leakage or intracranial infection occurred during the follow-up. Computed tomography reconstruction of skull base showed satisfactory reconstruction after surgery.

CONCLUSION

The use of in situ bone flap combined with vascular pedicled mucous flap to reconstruction of skull base defect after endonasal sphenoidal approach under neuroendoscopy has a lower incidence of cerebrospinal fluid leakage and lower complications, which has certain advantages and is worthy of clinical promotion.

Endoscopic endonasal pituitary surgery: How we do it. Consensus statement on behalf of the EANS skull base section

Introduction and research question

The use of an endoscope in skull base surgery provides a panoramic close-up view over the intracranial structures from multiple angles with excellent illumination, thus permitting greater extent of resection of tumors arising at sellar area, mostly represented by PitNet - Pituitary neuroendocrine tumors, with higher likelihood of preserving vital/intact gland tissue. For this refined specialty of neurosurgery, unique skills need to be acquired along a steep learning curve.

Material and methods

EANS (European Association of Neurosurgical Societies) skull base section panelists were enrolled and 11 completed the survey: the goal was to provide a consensus statement of the endoscopic endonasal approach for pituitary adenoma surgery.

Results

The survey consisted of 44 questions covering demographics data (i.e., academic/non-academic center, case load, years of experience), surgical techniques (i.e., use of neuronavigation, preoperative imaging), and follow-up management.

Discussion and conclusions

In this paper we identified a series of tips and tricks at different phases of an endoscopic endonasal pituitary surgery procedure to underline the crucial steps to perform successful surgery and reduce complications: we took in consideration the principles of the surgical technique, the knowledge of the anatomy and its variations, and finally the importance of adjoining specialties experts.

Treatment outcomes of neuroendoscopic and microscopic trans-sphenoidal pituitary adenomectomies and the effects on hormone levels

BACKGROUND

We aimed to compare the treatment outcomes of neuroendoscopic and microscopic trans-sphenoidal pituitary adenomectomies, as well as the effects on hormone levels and clinical symptoms.

METHODS

A total of 82 patients with pituitary adenomas that were surgically resected from June 2018 to March 2021 were selected and divided into a group receiving neuroendoscopic trans-sphenoidal pituitary adenomectomy (group A, N.=40), and the other group receiving microscopic surgery (group B, N.=42). Surgery-related indices, hormone levels before discharge and alleviation of symptoms 24 weeks after surgery were compared.

RESULTS

Both groups had significantly different degrees of tumor resection (P<0.05). The proportion of cases receiving total adenomectomy in group A significantly exceeded that of group B (P<0.05). The surgical time of group A was significantly longer than that of group B (P<0.05). Group A had significantly shorter mean hospitalization stay than that of group B (P<0.05). The postoperative hormone levels of both groups decreased significantly differently (P<0.05). Before discharge, the hormone recovery rate of group A significantly surpassed that of group B (P<0.05). The hormone levels of cases with prolactinoma, adrenocorticotropic hormone adenoma and growth hormone adenoma in group A dropped more significantly than those of group B did (P<0.05).

CONCLUSIONS

Compared with microscopic surgery, neuroendoscopic trans-sphenoidal pituitary adenomectomy worked more effectively, induced fewer postoperative complications and better promoted the postoperative recovery of hormone levels.

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.

The incidence and risk factors of unplanned reoperation in endoscopic endonasal surgeries: a single center study

The incidence of unplanned reoperation after surgery during the same hospitalization is considered one of most important evaluation indicators for health care quality. The purpose of this study was to determine the incidence and risk factors related to unplanned reoperation after an endoscopic endonasal approach (EEA). All patients who underwent elective endoscopic endonasal surgery from January 2016 to December 2021 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, were included. We identified the patients who underwent an unplanned reoperation and those who did not and divided them into two groups. The demographic data and risk factors were compared between the groups by univariate and multivariate logistic regression analyses. Of the 1783 patients undergoing EEA for various lesions of the skull base, the incidence of unplanned reoperation was 2.3%. The most common unplanned reoperations were repair of cerebrospinal fluid (CSF) leakage (39%), sellar hematoma evacuation (34.1%), hemostasis of epistaxis (14.6%) and external ventricular drainage for obstructive hydrocephalus (9.8%). The maximum diameter of tumor ≥ 3 cm (OR 2.654, CI 1.236-5.698; p = 0.012), meningioma (OR 4.198, CI 1.169-15.072; p = 0.028), craniopharyngioma (OR 5.020, CI 2.020-12.476; p = 0.001) and other sellar lesions (OR 4.336, CI 1.390-13.527; p = 0.012) and an operation time ≥ 240 min (OR 2.299, CI 1.170-4.518; p = 0.016) were the independent risk factors for unplanned reoperations in multivariate regression analysis. Of the 41 patients undergoing unplanned reoperation, 16 patients died, twenty-one patients had panhypopituitarism, 13 patients had transient and 6 had permanent diabetes insipidus, and 11 patients presented with intracranial infection and 6 of these patients were cured. By reviewing our department's data, we stated the incidence and risk factors for unplanned reoperation. It is important for the hospital administration and neurosurgeons to place more emphasis on these indicators. Furthermore, we suggest some effective quality improvement initiatives to reduce the incidence of unplanned reoperation.

Rhinologic outcome of endoscopic transnasal-transsphenoidal pituitary surgery: an institutional series, systematic review, and meta-analysis

PURPOSE

We aimed to summarize the available data on the objective rhinologic outcome after endoscopic transnasal-transsphenoidal (ETT) surgery.

METHODS

Retrospective study on a consecutive cohort of treatment-naïve patients undergoing ETT pituitary gland surgery. Additionally, a systematic review and meta-analysis with focus on the rhinologic outcome, including postoperative smell function was performed.

RESULTS

The institutional series incorporated 168 patients. A concomitant endoscopic septoplasty was performed in 29/168 patients (17.3%). A nasoseptal flap was used for reconstruction of large skull-base defects or high-flow CSF leaks in 4/168 (2.4%) patients. Early postoperative rhinologic complications (< 4 weeks) included epistaxis (3%), acute rhinosinusitis (1.2%) and late postoperative complications (≥ 8 weeks) comprised prolonged crusting (15.6%), symptomatic synechiae (11.9%) and septal perforation (0.6%). Postoperative smell function was not impaired (Fisher's exact test, p = 1.0). The systematic review included 19 studies on 1533 patients with a median postoperative epistaxis rate of 1.4% (IQR 1.0-2.2), a postoperative acute rhinosinusitis rate of 2.3% (IQR 2.1-3.0), a postoperative synechiae rate of 7.5% (IQR 1.8-19.1) and a postoperative septal perforation rate of 2.2% (IQR 0.5-5.4). Seven studies including a total of 206 patients reported adequate outcome measures for smell function before and after ETT surgery. Only 2/7 studies reported an impairment of smell function postoperatively, especially in patients with nasoseptal flap harvesting.

CONCLUSION

Early and late postoperative rhinologic complication rates after ETT surgery for pituitary lesions seem to be low. A thorough evaluation of smell function, in particular in patients at risk for nasoseptal flap harvesting, may be an important factor in optimal postoperative care.

Multi-layered repair of high-flow CSF fistulae following endoscopic skull base surgery without nasal packing or lumbar drains: technical refinements to optimise outcome

AIMS

Post-operative CSF leak remains a significant problem following endoscopic skull base surgery, particularly when there is a high-flow intra-operative CSF leak. Most skull base repair techniques are accompanied by the insertion of a lumbar drain and/or the use of nasal packing which have significant shortcomings. Our aim was to review the results of a large series of endoscopic skull base cases where a high-flow intra-operative CSF leak rate was encountered and repaired to assess if modifications in technique could reduce the post-operative CSF leak rate.

METHODS

A retrospective review of a prospectively maintained database of skull base cases performed by a single surgeon over a 10-year period was performed. Data regarding patient demographics, underlying pathology, skull base repair techniques and post-operative complications were analysed.

RESULTS

One hundred forty-two cases with high-flow intra-operative CSF leak were included in the study. The most common pathologies were craniopharyngiomas (55/142, 39%), pituitary adenomas (34/142, 24%) and meningiomas (24/142, 17%). The CSF leak rate was 7/36 (19%) when a non-standardised skull base repair technique was used. However, with the adoption of a standardised, multi-layer repair technique, the post-operative CSF leak rate decreased significantly (4/106, 4% vs. 7/36, 19%, p = 0.006). This improvement in the rate of post-operative CSF leak was achieved without nasal packing or lumbar drains.

CONCLUSION

With iterative modifications to a multi-layered closure technique for high-flow intra-operative CSF leaks, it is possible to obtain a very low rate of post-operative CSF leak, without lumbar drains or nasal packing.

Prediction of intraoperative cerebrospinal fluid leaks in endoscopic endonasal transsphenoidal pituitary surgery based on a deep neural network model trained with MRI images: a pilot study

Objective

This study aimed to investigate the reliability of a deep neural network (DNN) model trained only on contrast-enhanced T1 (T1CE) images for predicting intraoperative cerebrospinal fluid (ioCSF) leaks in endoscopic transsphenoidal surgery (EETS).

Methods

396 pituitary adenoma (PA) cases were reviewed, only primary PAs with Hardy suprasellar Stages A, B, and C were included in this study. The T1CE images of these patients were collected, and sagittal and coronal T1CE slices were selected for training the DNN model. The model performance was evaluated and tested, and its interpretability was explored.

Results

A total of 102 PA cases were enrolled in this study, 51 from the ioCSF leakage group, and 51 from the non-ioCSF leakage group. 306 sagittal and 306 coronal T1CE slices were collected as the original dataset, and data augmentation was applied before model training and testing. In the test dataset, the DNN model provided a single-slice prediction accuracy of 97.29%, a sensitivity of 98.25%, and a specificity of 96.35%. In clinical test, the accuracy of the DNN model in predicting ioCSF leaks in patients reached 84.6%. The feature maps of the model were visualized and the regions of interest for prediction were the tumor roof and suprasellar region.

Conclusion

In this study, the DNN model could predict ioCSF leaks based on preoperative T1CE images, especially in PAs in Hardy Stages A, B, and C. The region of interest in the model prediction-making process is similar to that of humans. DNN models trained with preoperative MRI images may provide a novel tool for predicting ioCSF leak risk for PA patients.

Intradural fat graft packing is not indispensable in preventing postoperative cerebrospinal fluid leakage in endoscopic endonasal pituitary adenoma surgeries

Objectives

Is intradural fat graft packing indispensable in preventing postoperative cerebrospinal fluid leakage in endoscopic endonasal pituitary adenoma surgeries? This study aimed to review the methods and outcomes of our graded sellar floor reconstruction strategy without fat graft packing in endoscopic endonasal pituitary adenoma surgeries.

Methods

From March 2018 to December 2022, 200 patients underwent endoscopic endonasal pituitary adenoma resection by a single author in our institute. We applied different graded skull base reconstruction strategies in different periods. Intradural fat graft packing was used to reconstruct the skull base in the early period, from March 2018 to June 2019, but fat graft was not used in the late period, from January 2020 to December 2022. The effect of these different graded skull base reconstruction strategies and whether intradural fat graft packing is necessary were evaluated by observing the incidence of postoperative cerebrospinal fluid leak.

Results

In the early period, fat graft was used to reconstruct skull base when the intraoperative cerebrospinal fluid (CSF) leakage existed. There were two patients who suffered from postoperative cerebrospinal fluid leak in this group. In the late period, fat graft was not used to reconstruct the skull base, and no patient suffered from postoperative cerebrospinal fluid leakage in this group.

Conclusions

Intradural fat graft packing is unnecessary in the endoscopic endonasal pituitary adenoma resection. The outcome of our graded sellar floor reconstruction strategy is satisfactory.

Formal Closure of Endoscopic Endonasal Skull Base Defects With a "Bow Tie" Tri-Layer Graft

OBJECTIVE

Risk factors for a postoperative cerebrospinal fluid leak (CSF) after surgery include an intraoperative high flow of CSF, elevated body mass index, defect size, and defect site. In our prior series, a high postoperative CSF leak rate for tumors of the central skull base (planum, sella, and clivus) appeared to be due to graft migration. We changed our closure technique from a single layer of collagen +/- fat graft to a novel graft, termed a "Bow tie" (a tri-layer fat graft with two pieces of collagen matrix), and report our results in this study.

METHODS

Retrospective temporal epoch study of a single otolaryngologist's experience of closing skull base defects in our skull base center from 2005 to 2017.

RESULTS

One hundred and forty-nine patients met inclusion criteria in two time periods, pre- and post-introduction of the Bow tie technique. In epoch I, from 2005 to 2013, 79 patients had reconstruction with a single layer of dural graft (25 had additional free fat graft). In epoch II, from 2014 to 2017, 70 patients had reconstruction with the Bow tie.

RESULTS

CSF leak rates were 8.7% overall: 15.2% in epoch I and 1.4% in epoch II (p = 0.01). After controlling the procedure, defects with a size greater than 2 cm had a 5.7 greater likelihood of failure. Epoch II had a lower incidence of major complications.

CONCLUSION

Using a single surgeon's experience, the multilayer Bow tie has a significant reduction in postoperative CSF leak and associated major complications for defects of the central skull base.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:1568-1575, 2023.

Surgical Anatomy and Approaches of the Anterior Cranial Fossa from a Transcranial and Endonasal Perspective

The anterior cranial fossa (ACF) is a complex anatomical region that can be affected by a broad spectrum of pathology. For the surgical treatment of these lesions, many approaches have been described, each of them with different scope and potential surgical complications, often associated with significant morbidity. Traditionally, tumors involving the ACF have been operated by transcranial approaches; however, in the last two decades, endoscopic endonasal approaches (EEAs) have been gaining popularity. In this work, the authors review and describe the anatomical aspects of the ACF and the technical nuances of transcranial and endoscopic approaches for tumors located in this region. Four approaches were performed in embalmed cadaveric specimens and the key steps were documented. Four illustrative cases of ACF tumors were selected to demonstrate the clinical application of anatomical and technical knowledge, which are essential in the preoperative decision-making process.

Endoscopic endonasal surgery for non-invasive pituitary neuroendocrinology tumors with incomplete pseudocapsule

Background

Pituitary neuroendocrinology tumors (PitNETs) with pseudocapsule can be effectively removed by the pseudocapsule-based extracapsular resection technique. In the areas without pseudocapsule, the tumor cells can spread into the adjacent tissues at the cellular level, which brings a great challenge to achieving total tumor resection.

Methods

Our surgical strategy for PitNETs with an incomplete pseudocapsule is to combine the pseudocapsule-based extracapsular resection technique with the intensive excision technique for the removal of the tumor. Specifically, the pseudocapsule-based extracapsular resection technique is applied in the areas with pseudocapsule, while in the areas without pseudocapsule, the intensive excision technique bounded by adjacent normal structures is adopted. Moreover, a pathological examination was performed to determine the situations of pseudocapsule and tumor cell remnant.

Results

All growth hormone-secreting PitNETs achieved biochemical remission after surgery. There was no deterioration of pituitary functions postoperatively, and the preoperative hypopituitarism had improved in all patients postoperatively. In total, two cases suffered a transient diabetes insipidus, and intraoperative cerebrospinal fluid leakage was observed in two cases but no postoperative cerebrospinal fluid leakage in all cases. There was no recurrence during the follow-up. The fragmental pseudocapsule and small tumor remnants were found in the majority of suspicious tissues by histological staining.

Conclusion

The effectiveness and safety of the surgical strategy were preliminarily explored for removing PitNETs without incomplete pseudocapsules. In overview, the pseudocapsule-based extracapsular resection technique is applied in areas with pseudocapsule, while the intensive excision bounded by adjacent normal structures is adopted in other areas.

Strategy of skull base reconstruction after endoscopic transnasal pituitary adenoma resection

Objective

Endoscopic endonasal surgery (EES) is commonly performed for resection of lesions of the anterior/middle cranial fossa region. Cerebrospinal fluid (CSF) leakage is a major complication. Skull base reconstruction after EES is challenging. We describe our reconstruction strategy and technique and analyze its outcomes.

Methods

We retrospectively analyzed 703 patients with pituitary adenoma who underwent EES in our center from January 2020 to August 2022. Clinical, imaging, operative, and pathologic data were recorded from the medical records and analyzed. Skull base reconstruction was performed to achieve the following three goals: seal the original leak, eliminate dead space, provide blood supply, and early ambulation. Reconstruction was tailored to individual patients based on grade of CSF leakage encountered during surgery.

Results

The number of patients with a grade 0, 1, 2, and 3 intraoperative CSF leak was 487, 101, 86, and 29, respectively. Overall incidence of postoperative CSF leakage was 0.14% (1/703). Fascia sutured and vascularized nasoseptal flap were selected for all grade 3 CSF leaks. One patient who experienced postoperative CSF leakage developed intracranial infection and were treated with lumbar CSF drainage that failed; eventually re-exploration surgery for repair was required. Other patients did not have complications such as CSF leak and infection. 29 patients with grade 3 CSF leakage did not complain of severe nasal complications after operation. No perioperative complications related to the strategy (overpacking, infections, or hematomas) occurred. Incidence of postoperative CSF leak according to intraoperative leak grade was as follows: grade 0, zero; grade 1, zero; grade 2, 1.16% (1/86); and grade 3, zero.

Conclusion

The principles of sealing the original leak, eliminating dead space, providing blood supply, and early ambulation are key in skull base reconstruction after EES. Individualization of these principles can significantly reduce the incidence of postoperative CSF leakage and intracranial infection and reduce the use of lumbar CSF drainage. Skull base suture technique is safe and effective in patients with high-flow cerebrospinal fluid leaks.

Risk Factors for Postoperative Cerebrospinal Fluid Leak after Graded Multilayer Cranial Base Repair with Suturing via the Endoscopic Endonasal Approach

This study analyzed risk factors for postoperative cerebrospinal fluid (CSF) leak after graded multilayer cranial base repair method with dural suturing. We performed surgery via the endoscopic endonasal approach (EEA) from 2012.6 to 2018.4, and those consecutive clinical data were prospectively accumulated and retrospectively analyzed. We tailored the repair method according to the intraoperative CSF leak grade. Among 388 surgeries via the EEA, there were 10 (2.6%) cases of postoperative CSF leak after graded repair with suturing. Postoperative CSF leak occurred in two of the 150 cases without intraoperative CSF leak (grade 0), one of the 104 cases with small (grade 1) intraoperative CSF leak, two of the 60 cases with moderate (grade 2) leak, and five of the 74 cases with large (grade 3) leak. Univariate analysis indicated that chordoma (P = 0.023), estimated tumor volume ≥ 7400 mm³ (P = 0.003), and maximum tumor diameter ≥ 32.5 mm (P = 0.001) were significant risk factors for postoperative CSF leak. Additionally, among cases with intraoperative grade 3 CSF leak, chordoma (P = 0.021), estimated tumor volume ≥ 23000 mm³ (P = 0.003), and maximum tumor diameter ≥ 45.5 mm (P = 0.001) were significant risk factors for postoperative CSF leak. Maximum tumor diameter, estimated tumor volume, and chordoma tumor pathology are related to a higher risk of postoperative CSF leak.

Skull Base Reconstruction following Surgical Treatment of Sinonasal Malignancies

Skull base defects following resection of anterior cranial fossa and sinonasal tumors are not uncommon. Advances in endoscopic techniques have allowed for entirely endonasal resection and reconstruction of these tumors. This article discusses techniques in the evaluation and management of anterior skull base defects.

Predictive model for preoperative risk calculation of cerebrospinal fluid leak after resection of midline craniofacial mass lesions

Background

Complex anterior skull base defects produced by resection of mass lesions vary in size and configuration and may be extensive. We analyzed the largest single-center series of midline craniofacial lesions extending intra- and extracranially. The study aims at the development of a predictive model for preoperative measurement of the risk of the postoperative cerebrospinal fluid (CSF) leak based on patients' characteristics and surgical plans.

Methods

166 male and 149 female patients with mean age 40,5 years (1 year and - 81 years) operated for benign and tumor-like midline craniofacial mass lesions were retrospectively analyzed using logistic regression method (Ridge regression algorithm was selected). The overall CSF leak rate was 9.6%. The ROSE algorithm and 'glmnet' software suite in R were used to overcome the cohort's disbalance and avoid overtraining the model.

Results

The most influential modifiable negative predictor of the postoperative CSF leak was the use of extracranial and combined approaches. Use of transbasal approaches, gross total resection, utilization of one or two vascularized flaps for skull base reconstruction were the foremost modifiable predictors of a good outcome. Criterium of elevated risk was established at 50% with a specificity of the model as high as 0.83.

Conclusions

The performed study has allowed for identifying the most significant predictors of postoperative CSF leak and developing an effective formula to estimate the risk of this complication using data known for each patient. We believe that the suggested web-based online calculator can be helpful for decision making support in off-pattern clinical situations.

CSF rhinorrhoea after endonasal intervention to the skull base (CRANIAL): A multicentre prospective observational study

Objective

Despite progress in endonasal skull-base neurosurgery, cerebrospinal fluid (CSF) rhinorrhoea remains common and significant. The CRANIAL study sought to determine 1) the scope of skull-base repair methods used, and 2) corresponding rates of postoperative CSF rhinorrhoea in the endonasal transsphenoidal approach (TSA) and the expanded endonasal approach (EEA) for skull-base tumors.

Methods

A prospective observational cohort study of 30 centres performing endonasal skull-base neurosurgery in the UK and Ireland (representing 91% of adult units). Patients were identified for 6 months and followed up for 6 months. Data collection and analysis was guided by our published protocol and pilot studies. Descriptive statistics, univariate and multivariable logistic regression models were used for analysis.

Results

A total of 866 patients were included - 726 TSA (84%) and 140 EEA (16%). There was significant heterogeneity in repair protocols across centres. In TSA cases, nasal packing (519/726, 72%), tissue glues (474/726, 65%) and hemostatic agents (439/726, 61%) were the most common skull base repair techniques. Comparatively, pedicled flaps (90/140, 64%), CSF diversion (38/140, 27%), buttresses (17/140, 12%) and gasket sealing (11/140, 9%) were more commonly used in EEA cases. CSF rhinorrhoea (biochemically confirmed or requiring re-operation) occurred in 3.9% of TSA (28/726) and 7.1% of EEA (10/140) cases. A significant number of patients with CSF rhinorrhoea (15/38, 39%) occurred when no intraoperative CSF leak was reported. On multivariate analysis, there may be marginal benefits with using tissue glues in TSA (OR: 0.2, CI: 0.1-0.7, p<0.01), but no other technique reached significance. There was evidence that certain characteristics make CSF rhinorrhoea more likely - such as previous endonasal surgery and the presence of intraoperative CSF leak.

Conclusions

There is a wide range of skull base repair techniques used across centres. Overall, CSF rhinorrhoea rates across the UK and Ireland are lower than generally reported in the literature. A large proportion of postoperative leaks occurred in the context of occult intraoperative CSF leaks, and decisions for universal sellar repairs should consider the risks and cost-effectiveness of repair strategies. Future work could include longer-term, higher-volume studies, such as a registry; and high-quality interventional studies.

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.

Multiportal Combined Endoscopic Endonasal and Transorbital Pathways: Qualitative and Quantitative Anatomic Studies of the "Connection" Skull Base Areas

BACKGROUND

Combined endonasal and transorbital multiportal surgery has been recently described for selected skull base pathologies. Nevertheless, a detailed anatomic description and a quantitative comprehensive anatomic study of the skull base areas where these 2 endoscopic routes converge, a so-called connection areas, are missing in the scientific literature.

OBJECTIVE

To identify all the skull base areas and anatomic structures where endonasal and transorbital endoscopic avenues could be connected and combined.

METHODS

Five cadaveric specimens (10 sides) were used for dissection. Qualitative description and quantitative analysis of each connection areas were performed.

RESULTS

At the anterior cranial fossa, the connection area was found at the level of the sphenoid planum; in the middle cranial fossa, it was at the Mullan triangle; finally, in the posterior cranial fossa, the connection area was just behind the medial portion of the petrous apex. The average extradural working areas through the transorbital approach were 4.93, 12.93, and 1.93 cm 2 and from the endonasal corridor were 7.75, 10.45, and 7.48 cm 2 at the level of anterior, middle, and posterior cranial fossae, respectively.

CONCLUSION

The combined endonasal and transorbital endoscopic approach is an innovative entity of skull base neurosurgery. From the anatomic point of view, our study demonstrated the feasibility of this combined approach to access the entire skull base, by both corridors, identifying a working connection area in each cranial fossa. These data could be extremely useful during the surgical planning to predict which portion of a lesion could be removed through each route and to optimize patients' care.

Postoperative protocols following endoscopic skull base surgery: An evidence-based review with recommendations

BACKGROUND

Postoperative management strategies for endoscopic skull base surgery (ESBS) vary widely because of limited evidence-based guidance.

METHODS

The PubMed, EMBASE, and Cochrane databases were systematically reviewed from January 1990 through February 2022 to examine 18 postoperative considerations for ESBS. Nonhuman studies, articles written in a language other than English, and case reports were excluded. Studies were assessed for levels of evidence, and each topic's aggregate grade of evidence was evaluated.

RESULTS

A total of 74 studies reporting on 18 postoperative practices were reviewed. Postoperative pain management, prophylactic antibiotics, and lumbar drain use had the highest grades of evidence (B). The literature currently lacks high quality evidence for a majority of the reviewed ESBS precautions. There were no relevant studies to address postoperative urinary catheter use and medical intracranial pressure reduction.

CONCLUSION

The evidence for postoperative ESBS precautions is heterogeneous, scarce, and generally of low quality. Although this review identified the best evidence available in the literature, it suggests the urgent need for more robust evidence. Therefore, additional high-quality studies are needed in order to devise optimal postoperative ESBS protocols.

Endoscopic Endonasal Transsphenoidal Approach to Repair Cerebrospinal Fluid Rhinorrhea After an Anterior Clinoidectomy for Aneurysm Clipping: Series of 4 Cases

BACKGROUND

Cerebrospinal fluid (CSF) rhinorrhea through a pneumatized optic strut is a known potential complication after an anterior clinoidectomy that is used to microsurgically clip a proximal internal carotid artery aneurysm. The original craniotomy site can be reopened to repair the skull base defect, but this technique has disadvantages.

OBJECTIVE

To avoid a repeat craniotomy and address the limitations of a transcranial approach, a straightforward alternative was used for skull base repair-the binostril endoscopic endonasal transsphenoidal approach.

METHODS

This retrospective case series describes the use of endoscopic transsphenoidal repair and outcomes for patients with CSF leaks after anterior clinoidectomy for aneurysm repair between January 1, 2015, and December 31, 2019.

RESULTS

Four adult patients (3 women and 1 man) with a mean age of 59.5 years were reviewed. Skull base repair occurred on average 24 days (range, 4-75 days) after the index operation. After demucosalization of the parasellar sphenoid sinus, the fistula in the pneumatized optic strut was reconstructed with a free nasal mucosal graft with or without an autologous muscle graft. None of the patients developed a recurrent CSF leak at a mean follow-up of 12.5 months (range, 8-22 months), and none experienced complications.

CONCLUSION

The endoscopic endonasal transsphenoidal approach was safe and effective for skull base repair in 4 patients with CSF rhinorrhea after an anterior clinoidectomy for aneurysm clipping.

Endoscopic Reconstruction of the Anterior Skull Base Following Tumor Resection: Application of a Novel Bioabsorbable Plate

OBJECTIVE

Endoscopic repair of skull base defects is required following resection of intracranial pathology via the endoscopic endonasal approach (EEA). Many closure techniques have been described, but choosing between techniques remains controversial. We report outcomes of 560 EEA procedures of skull base reconstruction performed on 508 patients over a 15-year-period. Halfway through this period, we adopted the use of a rigid, bioabsorbable extrasellar plate for reconstruction, enabling a comparison between this technique and those used previously.

METHODS

All patients undergoing EEA from 2005 to 2019 at our institution were retrospectively reviewed. Demographic information, surgical pathology, tumor dimensions and radiographic features, reconstructive technique, and patient-related outcomes were collected and analyzed with univariate and multivariate statistical modeling.

RESULTS

Five-hundred sixty procedures were performed on 508 patients. The series complication rate was 8.2%. Overall, cerebrospinal fluid (CSF) leak rate was 5.0% but varied significantly across closure techniques (p < 0.001). Critically, the CSF leak rate in the 272 cases prior to our 2013 adoption of the Resorb-X Plate (RXP) was 8.5%, whereas leak rate in the subsequent 288 cases was 1.7%. RXP was protective against CSF leak (p = 0.001), whereas gross total resection (GTR) correlated with increased leak rate (p = 0.001). Patient BMI was significantly associated with risk of leak (p = 0.047). Other variables did not impact leak risk.

CONCLUSION

Reconstructive technique, extent of resection, and patient BMI significantly contributed to CSF leak rate. GTR was associated with increased leak risk while the RXP was protective. The bioabsorbable RXP is an effective option for rigid skull base repair with comparatively few complications.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:1092-1098, 2023.

A simple surgical technique for sellar closure after transsphenoidal resection of pituitary adenomas in the context of risk factors for cerebrospinal fluid leaks and meningitis

OBJECTIVE

The transsphenoidal approach is the standard for most pituitary tumors. Despite low morbidity, postoperative CSF fistulas and meningitis are specific complications. Various surgical closure techniques for intraoperative CSF (iCSF) leak and sellar reconstruction have been described. For many years the authors have applied synthetic materials for iCSF leak repair and sellar closure in a standardized fashion in their department. Here they analyze the surgical outcome as well as risk factors for iCSF leak and meningitis.

METHODS

All patients with transsphenoidal resection of a pituitary adenoma performed by the same surgeon between January 2013 and December 2019 were screened retrospectively. A small amount of iCSF flow without a diaphragmatic defect was classified as a minor leak, and obvious CSF flow with or without a diaphragmatic defect was classified as a major leak. In case of iCSF leak, a fibrin- and thrombin-coated sponge was used to cover the diaphragmatic defect and another one was used for the sellar opening. A gelatin sponge was placed in the sphenoid sinus as an abutment. The primary and secondary outcomes were the number of postoperative CSF (pCSF) leaks and meningitis, respectively. Clinical, histological, and perioperative data from medical records were collected to identify risk factors for CSF leak and meningitis.

RESULTS

Of 417 transsphenoidal surgeries, 359 procedures in 348 patients with a median age of 54 years were included. There were 96 iCSF leaks (26.7%; 37.5% major, 62.5% minor). In 3 of 359 cases (0.8%) a pCSF fistula occurred, requiring revision surgery in 2 patients and a lumbar drain in 1 patient. Meningitis occurred in 3 of 359 cases (0.8%). All 3 patients recovered without sequelae after antibiotic therapy. According to univariate analysis, risk factors for iCSF leak were macroadenoma (p = 0.006) and recurrent adenoma (p = 0.032). An iCSF leak was found less often in functioning adenomas (p = 0.025). In multivariate analysis recurrent tumors remained as a risk factor (p = 0.021) for iCSF leak. Patients with iCSF leak were at increased risk for a pCSF leak (p = 0.005). A pCSF leak in turn represented the key risk factor for meningitis (p = 0.033).

CONCLUSIONS

Patients with macroadenomas and recurrent adenomas are especially at risk for iCSF leak. An iCSF leak in turn increases the risk for a pCSF leak, which carries the risk for meningitis. The authors' surgical technique leads to a very low rate of pCSF leaks and meningitis without using autologous graft materials. Hence, this technique is safe and improves patient comfort by avoiding the disadvantages of autologous graft harvesting.

Multidisciplinary Postoperative Care Pathway to Reduce Readmissions following Endoscopic Transsphenoidal Pituitary Surgery: Improving Quality of Patient Care

Background  Thirty-day unplanned readmission following endoscopic transsphenoidal pituitary surgery (ETPS) occurs in up to 14% of patients. Delayed hyponatremia is one of the most common causes, accounting for 30% of readmissions and often occurs within 1 week of surgery. The authors' prior retrospective review identified endocrinology follow-up as protective factor. Objectives  Implementation of a multidisciplinary postoperative care (POC) pathway: (1) to reduce 30-day hospital readmissions following ETPS and (2) improve inpatient and outpatient coordination of care with endocrinologist. Methods  This study is a single institution temporal cohort study of patients prior to (control cohort) and after implementation of the POC pathway (intervention cohort). The POC pathway utilized postdischarge 1 to 1.5 L/d fluid restriction, postoperative days 5 to 7 serum sodium, and endocrinology follow-up within 1 week of discharge to stratify patients into tiered hyponatremia regimens. Results  A total of 542 patients were included in the study, 409 (75%) in the control cohort and 133 (25%) in the intervention cohort. All-cause readmission was significantly reduced following implementation of the POC pathway (14 vs. 6%, p  = 0.015). Coordination with endocrinologist significantly increased in the inpatient (96 vs. 83%, p  < 0.001) and outpatient (77 vs. 68%, p  = 0.042) settings. Patients who were not in the POC pathway had the highest risk of readmission (odds ratio: 2.5; 95% confidence interval: 1.1-5.5). Conclusion  A multidisciplinary POC pathway incorporating endocrinologist in conjunction with postdischarge weight-based fluid restriction and postoperative serum sodium levels can safely be used to reduce 30-day readmissions following ETPS.

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.

Exploration of the causes of cerebrospinal fluid leakage after endoscopic endonasal surgery for sellar and suprasellar lesions and analysis of risk factors

Objective

Postoperative cerebrospinal fluid (CSF) leakage following endoscopic endonasal surgery (EES) is a frequent complication. This study aims to identify potential risk factors of postoperative CSF leakage.

Methods

A retrospective review of 360 patients who underwent EES was included. The associations between postoperative CSF leakage and patient demographics, medical history, tumor characteristics, and intraoperative repair techniques were analyzed; the diagnosis and repair of postoperative CSF leakage were also introduced.

Results

Postoperative CSF leakage occurred in 14 patients (3.9%), 2 of them cured by lumbar cistern drainage, 12 underwent endoscopic repair. Among these 12 cases, 3 were repaired twice, and the rest were cured the first time. During the repair surgery, insufficient embedded fat was detected in one case detected, seven with breached inner artificial dura, three had vascularized pedicle nasoseptal flap (VP-NSF) displacement, two with VP-NSF perforation, two with VP-NSF inactivation, and one with imperfect adherence to VP-NSF to the skull base. Eight cases had intracranial infections. Excluding one case who died of severe intracranial infection, the rest were cured and discharged without obvious sequelae. Multivariate analysis revealed that the suprasellar lesion, subarachnoid invasion, and intraoperative grade 3 flow CSF leakage were the risk factors of CSF leakage after operation, while the bone flap was a protective factor.

Conclusion

Bone flap combined with VP-NSF and iodoform gauze for skull base reconstruction is recommended in high-risk patients, while postoperative lumbar cistern drain remains dispensable.

Risk factors and management associated with postoperative cerebrospinal fluid leak after endoscopic endonasal surgery for pituitary adenoma

Objective

To determine risk factors and management for the development of a postoperative cerebrospinal fluid (CSF) leak after an endoscopic endonasal surgery (EES) for pituitary adenomas.

Methods

The clinical data of 400 patients who underwent EES for resection of pituitary adenomas from December 2018 to November 2019 in the Department of Neurosurgery of Beijing Tiantan Hospital were retrospectively reviewed. Age, gender, body mass index (BMI), tumor size, Knosp grade, suprasellar extension grade, sellar floor erosion grade, repeated transsphenoidal surgery, intraoperative CSF leak, use of pedicled nasoseptal flap and lumbar drain were collected and analyzed.

Results

Postoperative CSF leak occurred in 14 of 400 patients (3.5%). Age, gender, BMI, tumor size, Knosp grade and repeated transsphenoidal surgery were not risk factors for CSF leak. Suprasellar extension grade (≥B 6.0% vs. <B 1.4%; p = 0.024), sellar floor erosion grade (≥III 5.7% vs. <III 0.6%; p = 0.020) and intraoperative CSF leak (Yes 7.5% vs. No 2.0%; p = 0.009) were factors associated with an increased postoperative CSF leak rate.

Conclusions

Higher suprasellar extension grade, higher sellar floor erosion grade and intraoperative CSF leak were risk factors for postoperative CSF leak after endoscopic treatment of pituitary adenoma. Strict skull base reconstruction including use of a pedicled nasoseptal flap and perioperative lumbar drainage may avoid postoperative CSF leak.

Craniopharyngioma resection and aneurysm clipping performed simultaneously by pure endoscopic endonasal approach: A case report and literature review

Craniopharyngioma is one of the most challenging issues for neurosurgeons as a brain tumor. Among the approaches of neurosurgery, in comparison to craniotomy, the endoscopic endonasal approach (EEA) has risen in popularity over the last two decades; unruptured intracranial aneurysms are relatively commonly found in the general population. The EEA as a new paradigm in the treatment of aneurysm has been reported to successfully clip dozens of cases of intracranial aneurysm. However, when reviewing the domestic and foreign literature, it appeared that cases of craniopharyngioma complicated with intracranial aneurysm purely treated by EEA have not been reported so far. In the present study, the published literature regarding endoscopic endonasal surgery for craniopharyngioma and intracranial aneurysms was reviewed, accompanied with a case of craniopharyngioma complicated with intracranial aneurysm, both of which were simultaneously treated by EEA.

Duct-like diverticulum at the base of third ventricle tumors: a morphological signature diagnostic of papillary craniopharyngioma

This study describes and characterizes a narrow, hollow tubular structure, termed as duct-like diverticulum (DV), found specifically at the basal midline of papillary craniopharyngiomas (PCPs) located within the third ventricle (3V). The presence of this structure was systematically investigated on autopsy studies and magnetic resonance imaging (MRI) scans of 3536 craniopharyngioma (CP) cases published in the medical literature from 1911 to 2021, as well as in other twelve 3V tumor categories (n = 1470 cases). A basal DV was observed in a total of 50 PCPs, including two of our own cases. This DV corresponds to a tubular-shaped recess invaginated at the midline bottom of the tumor, following the same angled trajectory as the pituitary stalk. It can be easily seen as a hypointense linear structure on T1- and T2-weighted MRI scans, with two main length types: long DVs (74%), which reach the tumor center, and short DVs (26%), which penetrate the tumor only a few millimeters. The DV sign identifies the papillary CP type with a specificity of 100% and a sensitivity of 33% in the overall CP population. This finding also serves to establish the strictly intra-3V location of the lesion with a 95% specificity and 42% sensitivity among papillary CPs. No similar basal DV was found in adamantinomatous CPs nor among other categories of strictly 3V tumors. Consequently, the presence of a diverticulum in a 3V tumor represents a morphological signature pathognomonic of the papillary type and a valuable sign to reliably define the strictly 3V topography.

Advances in Pituitary Surgery

Pituitary surgery has advanced considerably in recent years with the exploration and development of various endoscopic approaches and techniques. Different endoscopic skull base approaches are being applied to access sellar tumors in different locations. Moreover, extracapsular dissection and cavernous sinus exploration have enabled gross total resection of sellar tumors where it could not have been achieved in the past. Techniques for skull base reconstruction have also progressed, allowing surgeons to remove larger and more complicated tumors than before. This review article discusses different endoscopic skull base approaches, surgical techniques for removing pituitary adenomas, and reconstruction methods for repairing postoperative low-flow and high-flow cerebrospinal fluid leakage.

Critical appraisal of minimally invasive keyhole surgery for intracranial meningioma in a large case series

Background

Meningioma surgery has evolved over the last 20 years with increased use of minimally invasive approaches including the endoscopic endonasal route and endoscope-assisted and gravity-assisted transcranial approaches. As the “keyhole” concept remains controversial, we present detailed outcomes in a cohort series.

Methods

Retrospective analysis was done for all patients undergoing meningioma removal at a tertiary brain tumor referral center from 2008–2021. Keyhole approaches were defined as: use of a minimally invasive “retractorless” approach for a given meningioma in which a traditional larger approach is often used instead. The surgical goal was maximal safe removal including conservative (subtotal) removal for some invasive locations. Primary outcomes were resection rates, complications, length of stay and Karnofsky Performance Scale (KPS). Secondary outcomes were endoscopy use, perioperative treatments, tumor control and acute MRI FLAIR/T2 changes to assess for brain manipulation and retraction injury.

Results

Of 329 patients, keyhole approaches were utilized in 193(59%) patients (mean age 59±13; 30 (15.5%) had prior surgery) who underwent 213 operations; 205(96%) were skull base location. Approaches included: endoscopic endonasal (n = 74,35%), supraorbital (n = 73,34%), retromastoid (n = 38,18%), mini-pterional (n = 20,9%), suboccipital (n = 4,2%), and contralateral transfalcine (n = 4,2%). Primary outcomes: Gross total/near total (>90%) resection was achieved in 125(59%) (5% for petroclival, cavernous sinus/Meckel’s cave, spheno-cavernous locations vs 77% for all other locations). Major complications included: permanent neurological worsening 12(6%), CSF leak 2(1%) meningitis 2(1%). There were no DVTs, PEs, MIs or 30-day mortality. Median LOS decreased from 3 to 2 days in the last 2 years; 94% were discharged to home with favorable 90-day KPS in 176(96%) patients. Secondary outcomes: Increased FLAIR/T2 changes were noted on POD#1/2 MRI in 36/213(17%) cases, resolving in all but 11 (5.2%). Endoscopy was used in 87/139(63%) craniotomies, facilitating additional tumor removal in 55%. Tumor progression occurred in 26(13%) patients, mean follow-up 42±36 months.

Conclusions & relevance

Our experience suggests minimally invasive keyhole transcranial and endoscopic endonasal meningioma removal is associated with comparable resection rates and low complication rates, short hospitalizations and high 90-day performance scores in comparison to prior reports using traditional skull base approaches. Subtotal removal may be appropriate for invasive/adherent meningiomas to avoid neurological deficits and other post-operative complications, although longer follow-up is needed. With careful patient selection and requisite experience, these approaches may be considered reasonable alternatives to traditional transcranial approaches.

Effects of cruciate embedding fascia-bone flap technique on grade II-III cerebral spinal fluid leak in endoscopic endonasal surgery

Background

Cerebral spinal fluid (CSF) leak remains an important issue in endoscopic endonasal surgery (EES). A standard protocol for skull base closure has not yet been established, and the application of rigid buttress has not been given sufficient attention. To emphasize the functions of support and fixation from rigid buttress in reconstruction, we introduced the cruciate embedding fascia-bone flap (CEFB) technique using autologous bone graft to buttress the fascia lata attachment to the partially sutured skull base dural defect and evaluated its efficacy in a consecutive case series of grade II–III CSF leaks in EES.

Methods

Data from consecutive patients diagnosed with sellar region lesions with grade II–III CSF leaks during EES were collected from May 2015 to May 2020. Skull base reconstructions were performed with the CEFB or the conventional pedicle vascularized nasoseptal flap (PNSF). Related clinical data were analysed. The combined use of the CEFB and PNSF was applied to an additional supplemental case series of patients with grade III leak and multiple high-risk factors.

Results

There were 110 and 65 patients included in the CEFB and PNSF groups, respectively. The CEFB demonstrated similar effects on the incidence of postoperative CSF leak (2.7%), intracranial infection (4.5%), and lumbar drainage (LD) placement (5.5%) as PNSF (3.1%, 3.1%, and 6.2%), but with less epistaxis (CEFB: 0%, PNSF: 6.2%) and nasal discomforts (CEFB: 0%, PNSF: 7.7%). The LD duration (CEFB: 6.67 ± 2.16 days, PNSF: 10.50 ± 2.38 days), bed-stay time (CEFB: 5.74 ± 1.58 days, PNSF: 8.83 ± 3.78 days) and hospitalization time (CEFB: 10.49 ± 5.51 days, PNSF: 13.58 ± 5.50 days) were shortened in the CEFB group. The combined use of CEFB and PNSF resulted in 0 postoperative CSF leaks in the supplemental case series of 23 highly susceptible patients.

Conclusion

This study suggested that the new CEFB technique has the potential to prevent postoperative CSF leak in EES. The results indicated that it can be used effectively without PNSF in suitable cases or applied in addition to a PNSF with high compatibility when necessary. Its effectiveness should be further verified with a larger cohort and better design in the next step.

Trial Registration Current Controlled Trials ChiCTR2100044764 (Chinese Clinical Trial Registry); date of registration: 27 March 2020. Retrospectively registered

Risk Factors and Reconstruction Techniques for Persistent Cerebrospinal Fluid Leak in Patients Undergoing Endoscopic Endonasal Approach to the Posterior Fossa

Background High-flow skull base dural defects are associated with an increased risk of postoperative cerebrospinal fluid (CSF) leaks.

Objective This study aimed to identify the risk factors for persistent postoperative CSF leak after endoscopic endonasal surgery (EES) and determine the ideal reconstruction strategy after initial failed repair.

Methods Patients with CSF leak after intradural EES between October 2000 and February 2017 were identified. Cases with persistent CSF leak were compared with patients with similar pathologic diagnosis without a persistent leak to identify additional risk factors.

Results Two hundred and twenty-three out of 3,232 patients developed postoperative CSF leak. Persistent leaks requiring more than one postoperative repair occurred in 7/223 patients (3.1%). All seven had undergone intradural approach to the posterior fossa for resection of recurrent/residual clival chordomas. This group was matched with 25 patients with recurrent/residual clival chordoma who underwent EES without postoperative CSF leak (control group). Age, gender, history of diabetes, smoking, or radiotherapy were not statistically different between the groups. Obesity (body mass index > 30) was significantly more common in the group with persistent leak (86%) compared with controls (36%) (p = 0.02). All patients with a persistent CSF leak developed meningitis (p = 0.001). Five patients with persistent leak required a pericranial flap to achieve definitive repair.

Conclusion Multiple recurrent CSF leak after EES primarily occurs following resection of recurrent/residual posterior fossa chordoma. Obesity is a major risk factor and meningitis is universal with persistent leak. Flap necrosis may play a role in the development of persistent CSF leaks, and the use of secondary vascularized flaps, specifically extracranial–pericranial flaps, should be considered as an early rescue option in obese patients.

Clinical Efficacy of the Multilayered Skull Base Reconstruction Using In Situ Bone Flap in Endoscopic Endonasal Approach for Craniopharyngioma

Objective  The aim of the study is to summarize and analyze the efficacy of the multilayered skull base reconstruction using in situ bone flap in endoscopic endonasal approach (EEA) for craniopharyngiomas. Methods  A retrospective review of 65 patients who underwent resection of their histopathology confirmed craniopharyngiomas performed at a single institution. Based on the team's understanding and mastery of skull base reconstruction techniques, patients were divided into two groups according to the methods of reconstruction in two periods. First (March 2015 through August 2016), osseous reconstruction was not adopted and served as the control group (34 cases). Second (September 2016 through July 2019), in situ bone flap repair of the skull base (complete osseous reconstruction) served as observation group (31 cases). The length of hospitalization and nasal exudation, bed rest time of hospital discharge, the incidence of cerebrospinal fluid leaks, lumbar drainage, and intracranial/pulmonary infections were collected and compared. Results  Compared with the control group, patients in the observation group had obviously less lumbar drainage and CSF leakage ( p  < 0.05), but had no significant difference in cases of re-operation, meningitis, and pulmonary infection. At the meantime, cases of nasal exudation, bed rest, and hospitalization of the observation group were significantly reduced ( p  < 0.05) in the observation group. Conclusion  The multilayered reconstruction technique (especially using in situ bone flap, combined with vascularized pedicled nasoseptal flap) is a safe and effective method in achieving watertight closure after EEEA, and can significantly reduce the incidence of cerebrospinal fluid leaks, and facilitate rehabilitation in skull base reconstruction of craniopharyngiomas.

Dural Invasion as a Marker of Aggressive Pituitary Adenomas

BACKGROUND

Predictive markers of aggressive pituitary tumors have not been consistently demonstrated. Dural invasion and invasion-associated proteins, including matrix metalloproteinase-9 (MMP9) and cofilin, have been proposed to predict aggressive behavior and recurrence, but findings to date have been inconsistent.

OBJECTIVE

To assess whether microscopic dural invasion predicts aggressive pituitary adenoma behavior and whether MMP9 and cofilin expression correlates with pathological and clinical invasion markers.

METHODS

We retrospectively studied 328 consecutive pituitary mass resections by a single neurosurgeon at a single center; 254 were adenomas, and 98 had dural biopsies sent for routine pathological evaluation. Assessments included clinical features, postoperative course, and immunochemical expression of MMP9, cofilin, and phospho-cofilin. Recurrence was evaluated in those with at least 12 months of postoperative follow-up.

RESULTS

Dural invasion was evident in 48% of biopsy specimens and was associated with male sex, larger tumors, suprasellar extension and sphenoid sinus invasion, cranial nerve palsies, and hypogonadism. Recurrence rates and the expression of MMP9, cofilin, and phospho-cofilin did not differ between those with and without dural invasion. However, differential expression of phospho-cofilin was associated with growth hormone deficiency and compressive pituitary mass effects.

CONCLUSION

Dural invasion is associated with larger tumors, suprasellar and sphenoid sinus invasion, and pituitary failure but is not predictive of a more aggressive postoperative course. Routine dural biopsy is therefore of limited benefit in predicting postoperative recurrences. Cofilin expression may be an adjunctive biomarker of invasion in recurrent tumors, but MMP9 expression does not predict tumor behavior.

Evaluation of early postoperative day 1 discharge after endoscopic endonasal pituitary adenoma resection

OBJECTIVE

While multiple studies have evaluated the length of stay after endonasal transsphenoidal surgery (ETS) for pituitary adenoma, the potential for early discharge on postoperative day 1 (POD 1) remains unclear. The authors compared patients discharged on POD 1 with patients discharged on POD > 1 to better characterize factors that facilitate early discharge after ETS.

METHODS

A retrospective chart review was performed for patients undergoing ETS for pituitary adenoma at a single tertiary care academic center from February 2005 to February 2020. Discharge on POD 1 was defined as a discharge within 24 hours of surgery.

RESULTS

A total of 726 patients (mean age 55 years, 52% male) were identified, of whom 178 (24.5%) patients were discharged on POD 1. These patients were more likely to have pituitary incidentaloma (p = 0.001), require dural substitutes and DuraSeal (p = 0.0001), have fewer intraoperative CSF leaks (p = 0.02), and have lower postoperative complication rates (p = 0.006) compared with patients discharged on POD > 1. POD 1 patients also showed higher rates of macroadenomas (96.1% vs 91.4%, p = 0.03) and lower rates of functional tumors (p = 0.02). POD > 1 patients were more likely to have readmission within 30 days (p = 0.002), readmission after 30 days (p = 0.0001), nasal synechiae on follow-up (p = 0.003), diabetes insipidus (DI; 1.7% vs 9.8%, p = 0.0001), postoperative hypocortisolism (21.8% vs 12.1%, p = 0.01), and postoperative steroid usage (44.6% vs 59.7%, p = 0.003). The number of patients discharged on POD 1 significantly increased during each subsequent time epoch: 2005-2010, 2011-2015, and 2016-2020 (p = 0.0001). On multivariate analysis, DI (OR 7.02, 95% CI 2.01-24.57; p = 0.002) and intraoperative leak (OR 2.02, 95% CI 1.25-3.28; p = 0.004) were associated with increased risk for POD > 1 discharge, while operation epoch (OR 0.46, 95% CI 0.3-0.71; p = 0.0001) was associated with POD 1 discharge.

CONCLUSIONS

This study demonstrates that discharge on POD 1 after ETS for pituitary adenomas was safe and feasible and without increased risk of 30-day readmission. On multivariate analysis, surgical epoch was associated with decreased risk of prolonged length of stay, while factors associated with increased risk of prolonged length of stay included DI and intraoperative CSF leak. These findings may help in selecting patients who are deemed reasonable for safe, early discharge after pituitary adenoma resection.

Clinical Outcomes of Transcranial and Endoscopic Endonasal Surgery for Craniopharyngiomas: A Single-Institution Experience

Objective

Craniopharyngioma has always been a challenge for the neurosurgeon, and there is no consensus on optimal treatment. The objective of this study was to compare surgical outcomes and complications between transcranial surgery (TCS) and endoscopic endonasal surgery (EES) of craniopharyngiomas.

Methods

A retrospective review of patients who underwent craniopharyngioma resection at Wuhan Union Hospital between January 2010 and December 2019 was performed. A total of 273 patients were enrolled in this retrospective study. All patients were analyzed with surgical effects, endocrinologic outcomes, complications, and follow-up results.

Results

A total of 185 patients underwent TCS and 88 underwent EES. There were no significant differences in patient demographic data, preoperative symptoms, and tumor characteristics between the two groups. The mean follow-up was 30.5 months (range 8–51 months). The EES group had a greater gross total resection (GTR) rate (89.8% EES vs. 77.3% TCS, p < 0.05) and lower rate of hypopituitarism (53.4% EES vs. 68.1% TCS, p < 0.05) and diabetes insipidus (DI) (51.1% EES vs. 72.4% TCS, p < 0.05). More postoperative cerebrospinal fluid (CSF) leaks occurred in the EES group (4.5% EES vs. 0% TCS, p < 0.05). More patients in the EES group with preoperative visual deficits experienced improvement after surgery (74.5% EES vs. 56.3% TCS, p < 0.05). There were statistical differences in the recurrence rates (12.5% EES vs. 23.8% TCS, p < 0.05) between the 2 groups.

Conclusion

These data support the view that EES is a safe and effective minimally invasive surgery compared to TCS. Compared to TCS, EES has fewer surgical complications and a lower recurrence rate.

Surgical complications of endoscopic approach to skull base: analysis of 584 consecutive patients

PURPOSE

Endoscopic techniques have been widely applied for challenging cranial base surgeries in recent years. In this study, we evaluated the safety and efficacy of using the endoscopic endo-nasal route for various skull base pathologies in terms of postoperative complications.

METHODS

A total of 584 consecutive patients who underwent endoscopic skull base surgery were studied. Peri- and post-operative complications and risk factors affecting the occurrence of these complications were evaluated.

RESULTS

648 endoscopic skull base surgical procedures were performed on 584 patients (47.8% females and 52.2% males) with the mean age of 41.2 years. Pituitary adenoma (69.3%) was the most common pathology. Post-operative mortality was 2.0%. The rates of post-operative permanent neurological deficit (one case of 6th nerve injury, two 12th nerve injuries and one hemiparesis) and visual deterioration were 0.6% and 1.5%, respectively. Ten patients (1.7%) were complicated with meningitis and it was the cause of death in 3. Systemic complications not directly attributable to skull base surgical access occurred in 2% (11 patients) with 5 mortalities. The rate of intra-operative vascular injury was 1% and among them one patient died due to PCA injury. The most common post-operative complications were diabetes insipidus (12.5%), anterior pituitary dysfunction (10.6%) and CSF leak (3.6%), respectively. In general, reoperation, malignant lesions, and level IV of surgical complexity were associated with a higher incidence of complications.

CONCLUSION

Endoscopic endo-nasal approach can be a safe and less-morbid first-line treatment of patients with various skull base lesions.