Predicting post-operative cerebrospinal fluid (CSF) leak following endoscopic transnasal pituitary and anterior skull base surgery: a multivariate analysis

Does Cerebrospinal Fluid Leak in Pituitary Surgery Affect Patient Reported Quality of Life?

BACKGROUND

Endoscopic techniques allow for improved visualization and tumor debulking of pituitary adenomas. More thorough tumor resection, however, can be associated with higher rates of CSF leaks. We set out to determine if CSF leaks influenced patient perceived quality of life outcomes.

METHODS

This retrospective study included 152 patients who underwent endoscopic pituitary tumor resection over a 10-year period. QoL was assessed using the SF-36 questionnaire and completed before surgery, 6 weeks and 6 months post-operatively. Statistical analysis was conducted using a equivalence test and a two-way mixed model ANOVA to assess intraoperative CSF leak, postoperative CSF leak, redo surgery, and the use of a lumbar drain.

RESULTS

Of the 152 patients, 98 had a potential intraoperative CSF leak. Intra- and postoperative CSF leaks did not significantly impact patient reported QoL outcomes at 6 months following surgery. There was clinical equivalence in mental scores as early as 6 weeks and 6 months for physical scores. There was no statistically significant difference in physical (p-value = 0.975) and mental (p = 0.204) scores for patients who experienced a postoperative CSF leak. There was no statistically significant difference in QoL in the mental and physical scores for patients that received a lumbar drain (physical score p = 0.832; mental score p = 0.915) or redo surgery (physical score p = 0.830; mental score p = 0.204).

CONCLUSION

This article demonstrates that CSF leaks do not impact patient-reported QoL outcomes at 6 months post-surgery. This will allow surgeons to better provide insight and counsel patients regarding the relevance of CSF leaks in the setting of pituitary procedures.

LEVEL OF EVIDENCE

3 Laryngoscope, 135:1970-1974, 2025.

Suprasellar Anterior-Posterior Diameter Optimizes the Use of Intraoperative MRI in Patients Undergoing Endoscopic Pituitary Surgery

BACKGROUND AND OBJECTIVES

Intraoperative MRI (iMRI) has been demonstrated to improve the extent of resection of pituitary neuroendocrine tumors resected using endoscopic endonasal approaches. We sought to establish if preoperative clinicoradiological parameters could be used to predict which patients are most likely to benefit from iMRI and thus allow more efficient use of this technology.

METHODS

A prospectively maintained surgical database of all endoscopic pituitary tumor resections with iMRI guidance performed between May 2017 and September 2023 was accessed. Data were collected on clinical and radiological parameters that may predict reintervention after iMRI. Logistic regression models were constructed to assess the relationship between predictor variables and reintervention after iMRI.

RESULTS

Seventy-three patients were included in the study. After review of the iMRI, 24/73 (33%) patients underwent surgical reintervention. The combined rate of gross total resection/near total resection was 64/73 (88%). The rate of biochemical cure of endocrine disease after surgery for a hormonally active tumor was 15/21 (71%). On univariate logistic regression analysis, the only factor significantly associated with reintervention after iMRI was the suprasellar anterior-posterior diameter (odds ratio 1.1, 95% CI 1.01-1.2, P = .030).

CONCLUSION

Suprasellar anterior-posterior diameter ≥15 mm predicts the requirement for reintervention after endoscopic resection of pituitary neuroendocrine tumor. Use of this easily obtained radiological parameter will allow iMRI to be used in those patients who are most likely to benefit.

Resection of craniopharyngiomas: comparison between gross total resection and subtotal resection with adjuvant radiation

PURPOSE

The surgical treatment of craniopharyngiomas (CPs) remains a challenge, with significant variability in the literature.

METHODS

we therefore analyze current studies to demonstrate how the field has changed over the years.

RESULTS

Achieving a gross total resection for these histologically benign lesions often poses significant difficulty based on their proximity, adherence, or invasion of adjacent critically important neuronal and vascular structures. In our historical literature, gross-total resection from transcranial surgery often carried high morbidity leading some to advocate for subtotal resection paired with postoperative radiotherapy as a preferable strategy. The advent of the extended endonasal endoscopic approach has led to a reconsideration of this tactic.

CONCLUSIONS

In this review, we discuss several of the studies that led to the current understanding of surgical options for craniopharyngiomas and discuss how the endonasal approach and more recent published results may modify surgical thinking.

Operative considerations for resection of pituitary adenoma in patients with sickle cell disease: A retrospective analysis of 19,653 patients

Background

Sickle cell disease (SCD) is a hemoglobinopathy that affects over 30 million individuals worldwide. When significant "sickling" occurs, blood flow to specific organs can be impaired, resulting in ischemia or infarction. This can be problematic during intracranial surgery, in which low systemic circulatory volume due to significant blood loss can lead to intracranial hypotension. Using a multivariable modeling approach, we gathered a large patient dataset through a nationally representative database to inform future neurosurgical management of patients with concurrent SCD and pituitary adenoma.

Methods

We queried the Healthcare Cost and Utilization Project Nationwide Readmissions Database and implemented discharge weighting to identify a cohort of SCD patients who had undergone surgical resection of pituitary adenoma between 2015 and 2016. Variables investigated included patient age, sex, length of stay, postoperative complications and outcomes, payment methods, and median income, among several others.

Results

Retrospective analysis identified 19,612 non-sickle cell patients (NSCP) and 41 SCD patients. Complication profiles for the SCD cohort demonstrated significantly higher rates of postoperative pulmonary embolism (P = 0.042) and pneumonia (P = 0.005) compared to those of the NSCP cohort. In addition, the SCD cohort trended toward higher rates of readmission (15.25% vs. 9.76%) and deep vein thrombosis, although neither achieved statistical significance (P = 0.45 and 0.07, respectively).

Conclusion

SCD is a severe disorder that affects many individuals worldwide and represents a significant risk factor for complications and adverse outcomes in pituitary adenoma surgery. Further research is needed to explore SCD as a risk factor in pituitary surgery and the role it may play in perioperative complications.

Predictive Factors for Postoperative Cerebrospinal Fluid Drainage in Neurosurgical Management of Intracranial Aneurysms

BACKGROUND

Management of intracranial aneurysms (IAs) often requires complex neurosurgical interventions, with some patients necessitating postoperative cerebrospinal fluid (CSF) drainage. Identifying predictive factors for CSF drainage can enhance patient outcomes through targeted interventions and improved perioperative care.

METHODS

In this retrospective study, 151 patients who underwent surgical treatment for IAs were included. Demographic data, clinical presentation (Hunt-Hess grade and modified Fisher score), surgical details (operative time and intraoperative complications), and postoperative outcomes were reviewed. Both univariate and multivariable logistic regressions were conducted to identify predictors of postoperative CSF drainage. A subgroup analysis compared patients with anterior versus posterior circulation aneurysms.

RESULTS

Overall, 67 patients required postoperative CSF drainage. On multivariable analysis, age ≥60 years, high Hunt-Hess grade, operative time >5 hours, and intraoperative aneurysm rupture significantly increased the odds of drainage (P < 0.05). Subgroup analysis revealed that these risk factors conferred an even higher likelihood of CSF drainage in posterior circulation aneurysms. Gender and modified Fisher score did not show significant associations with drainage.

CONCLUSIONS

Advanced age, high Hunt-Hess grade, prolonged operative time, and intraoperative rupture predict postoperative CSF drainage in patients with IAs. Incorporating both global and subgroup-based risk assessments can help refine perioperative strategies to reduce complications and improve patient outcomes.

Advancement in perioperative management of pituitary adenomas-Current concepts and best practices

Pituitary adenomas are very common representing 18.1% of all brain tumors and are the second most common brain pathology. Transsphenoidal surgery is the mainstay of treatment for all pituitary adenomas except for prolactinomas which are primarily treated medically with dopamine agonists. A thorough endocrine evaluation of pituitary adenoma preoperatively is crucial to identify hormonal compromise caused by the large sellar mass, identifying prolactin-producing tumors and comorbidities associated with Cushing and acromegaly to improve patient care and outcome. Transsphenoidal surgery is relatively safe in the hands of experienced surgeons, but still carries a substantial risk of causing hypopituitarism that required close follow-up in the immediate postoperative period to decrease mortality. A multidisciplinary team approach with endocrinologists, ophthalmologists, and neurosurgeons is the cornerstone in the perioperative management of pituitary adenomas.

Conventional clinical signs and symptoms are poor predictors of postoperative cerebrospinal fluid leak: A single-centre cohort perspective

BACKGROUND

Postoperative cerebrospinal fluid (CSF) leak remains a concerning complication of the endoscopic endonasal approach (EEA) for skull base pathology. Signs and symptoms suggesting CSF leak often trigger additional workup during the postoperative course. We systematically evaluate associations between subjectively reported clinical signs/symptoms noted during the immediate postoperative period and incidence of postoperative CSF leaks.

METHODS

Retrospective chart review was conducted at a tertiary academic medical centre including 137 consecutive patients with intraoperative CSF leak during EEA with primary repair between July 2018 and August 2022. Postoperative CSF leak associations with clinical signs and symptoms were evaluated using positive (PPV) and negative predictive values (NPV), sensitivity, specificity and odds ratio (OR) via univariate logistic regression.

RESULTS

Seventy-nine patients (57.7%) had high-flow leaks repaired and 5 (3.6%) developed CSF leaks postoperatively. Of reported symptoms, rhinorrhea was most common (n = 52, 38.0%; PPV [95% CI] = 7.6% [4.8%, 11.9%]), followed by severe headache (n = 47, 34.3%; 6.3% [3.1%, 12.5%]), dizziness (n = 43, 31.4%; 2.3% [0.4%, 12.1%]), salty or metallic taste (n = 20, 14.6%; 9.9% [3.3%, 25.8%]), and throat drainage (n = 10, 7.3%; 9.9% [1.7%, 41.4%]). Nausea or vomiting constituted the most reported sign concerning for CSF leak (n = 73, 53.3%; PPV [95% CI] = 4.1% [2.0%, 8.1%]). On univariate regression, no sign or symptom, including rhinorrhea (OR [95% CI] = 7.00 [0.76-64.44]), throat drainage (3.42 [0.35-33.86]), salty/metallic taste (4.22 [0.66-27.04]), severe headache (3.00 [0.48-18.62]), dizziness (0.54 [0.06-4.94]), fever (3.16 [0.50-19.99]), and nausea/vomiting (1.33 [0.22-8.21]), associated with postoperative CSF leak.

CONCLUSIONS

A range of subjectively reported symptoms and signs failed to predict postoperative CSF leak. Further investigation is warranted to inform appropriate attention and response.

3 Tesla intra-operative MRI as an adjunct to endoscopic pituitary surgery: an early assessment of clinical utility

BACKGROUND

Extent of resection is a major determinant of outcomes following pituitary surgery. Intra-operative magnetic resonance imaging (iMRI), provides an immediate assessment of the extent of resection, allowing further tumour resection during the same procedure. However, such systems are expensive and significantly increase operative time, prompting some authors to question the additional benefit conferred by iMRI when combined with endoscopy. Our aim was to assess the impact of combining 3 T iMRI with endoscopy in patients with pituitary tumours.

METHODS

We retrospectively reviewed a prospectively maintained database to identify patients who underwent iMRI guided endoscopic resection of pituitary tumours between May 2017 and November 2018 (iMRI cohort). This cohort was compared with a pre-iMRI cohort of patients who underwent endoscopic resection of pituitary adenomas. Operative time, extent of resection, control of endocrine disease and post-operative complications were recorded and analysed.

RESULTS

Thirty-seven patients were included in each cohort. iMRI facilitated additional tumour resection in 6/37 (16%) of cases. In 4/37 cases (11%), iMRI prompted a return to theatre but no further tumour could be identified. The overall GTR rate, following iMRI was 24/37 (65%) as compared to 21/37 (57%) in the pre-iMRI cohort. Cure of endocrine disease associated with hormonally active tumours was achieved in 9/11 (82%) of cases in the iMRI cohort. The mean operative time in the iMRI cohort was 327 minutes (five hours 27 minutes).

CONCLUSIONS

3 T iMRI provides immediate identification of residual tumour following endoscopic pituitary surgery. This allows for resection of surgically accessible residual disease during the same procedure and is likely to reduce the requirement for later re-intervention. However, the use of iMRI in this setting is associated with significant resource allocation issues which must be considered prior to the widespread adoption of this technique.

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.

The Predictors of Postoperative Cerebrospinal Fluid Leak in Endoscopic Endonasal Pituitary Surgery: The Role of Tumor Volume

Objectives  Postoperative cerebrospinal fluid (Po-CSF) leak is still a challenging complication of endoscopic endonasal skull base surgery. However, data describing the predictive factors of Po-CSF leak in pure pituitary adenomas is lacking. Aim of this study is to determine the risk factors of Po-CSF leak in a pituitary adenoma group operated via pure transsellar endoscopic approach. Design  This is a retrospective cohort study. Setting  A single-center academic hospital. Participants  Patients operated for a pituitary adenoma between 2015 and 2021 and followed up until June 2022 were included. Main Outcome Measures  Demographics, comorbidities, imaging, and outcome were recorded. Univariate and multivariate logistic regression analyses were used to determine the risk factors of Po-CSF leak. Results  Of the total 170 patients with a mean age of 47.5 ± 13.8 (min: 15; max: 80), 11 (6.5%) had Po-CSF leak. Univariate analysis revealed age, diabetes mellitus (DM), and tumor volume as predictors of Po-CSF leak. According to the receiver operating characteristic analysis, 7.5 cm 3 of tumor volume was found to be a good cutoff value with a sensitivity of 82% and a specificity of 75%. Hence, multivariable logistic regression model adjusted by age showed that a tumor volume of > 7.5 cm 3 (odds ratio [OR]: 22.9; 95% confidence interval [CI]: 3.8-135.9, p  = 0.001) and DM (OR: 8.9; 95% CI: 1.7-46.5; p  = 0.010) are strong independent risk factors of Po-CSF leak in pure endoscopic endonasal pituitary surgery. Conclusion  Besides younger age and DM, a cutoff value for tumor volume > 7.5 cm 3 is the most remarkable risk factor for Po-CSF leak in pure endoscopic pituitary surgery. These patients should carefully be assessed preoperatively and potential preemptive surgical strategies should be taken into consideration to avoid complications.

Clinical and Surgical Outcomes of Endoscopic Endonasal Approach for Giant Pituitary Adenomas: Analysis of Predictive Factors

BACKGROUND

Giant pituitary adenomas (GPAs) are defined as tumors with ≥40 mm in any maximum diameter, and these tend to invade multiple intracranial compartments. Hence, treatment remains a surgical challenge.

OBJECTIVE

To describe the clinical and surgical outcomes of the endoscopic endonasal approach (EEA) for GPA in a pituitary referral center in Latin America and to analyze associated predictive factors.

METHODS

37 patients with histologically-confirmed GPA treated solely through the EEA between a 2-year period were included. Preoperative and postoperative clinical and neuroimaging findings; surgical morbidity and mortality; and binary logistic regression analysis to assess predictive factors were analyzed.

RESULTS

Preoperative visual impairment prevalence was 97.3%. Mean tumor volume was 32 cc and gross total resection rate was 40.5%. Favorable visual acuity and visual fields outcome rate was 75% and 82.9%, respectively. In the multivariate analysis, bilateral cavernous sinus invasion (P = 0.018) and postoperative cerebrospinal fluid (CSF) leak (P = 0.036) were associated with an unfavorable visual acuity outcome, while radiation therapy (P = 0.035) was for visual fields. Similarly, intraoperative CSF leak was a predictive factor for postoperative CSF leak (10.8%) (P = 0.042) and vascular injury (13.5%) (P = 0.048).

CONCLUSIONS

In this first Mexican clinical series, we demonstrated that the EEA is a safe and effective technique for GPA, although early diagnosis and prompt intervention may promote further visual function preservation without significant endocrine morbidity.

Validity of the flap risk score in predicting nasoseptal flap use after endoscopic transsphenoidal pituitary mass resection

Introduction

There remains a paucity of literature examining the decision algorithm for use of nasoseptal flap (NSF) after endoscopic endonasal approaches (EEA) to pituitary adenoma resection. In 2018, we published the first ever flap risk score (FRS) to predict the use of NSF. We present here a validity study examining the FRS as applied to our center.

Methods

A retrospective review was completed of consecutive patients undergoing EEA from January 2015 to March 2021. The sensitivity, specificity, and predictive value of the FRS were calculated. A multivariate logistic model was used to determine the relative weight imaging characteristics in predicting need for NSF. The relative weighting of the FRS was then re-optimized.

Results

A total of 376 patients underwent EEA for pituitary adenoma resection, with 113 (30.1%) requiring NSF. The FRS had a sensitivity and specificity of 43.4% and 94.7%, respectively. Sphenoid sinus extension increased the odds of needing a NSF equivalent to 19 mm of tumor height, as opposed to 6 mm in the original 2018 cohort. The re-optimized model had sensitivity and specificity of 79.6% and 76.4%, respectively.

Conclusion

We present a validity study examining the utility of FRS in predicting the use of NSF after EEA for pituitary adenoma resection. Our results show that while FRS is still predictive of the need for NSF after EEA, it is not as predictive now as it was for its original cohort. Therefore, a more comprehensive model is necessary to more accurately stratify patients' preoperative risk for NSF.

Risk Factors Associated with Postoperative CSF Leak in Extrasellar Tumors

Objective  While postoperative cerebrospinal fluid (CSF) leak rates of pituitary tumors have been frequently studied, there are fewer studies examining postoperative CSF leak rates for extrasellar tumors. The purpose of this study was to identify risk factors for the development of postoperative CSF leak in patients undergoing endoscopic surgery for extrasellar tumors. Methods  A retrospective chart review was done for patients who underwent endoscopic resection for extrasellar tumors between 2008 and 2020. Age, gender, tumor type, tumor location, tumor size, reconstruction technique, medical comorbidities, and other potential risk factors were identified. Data was analyzed to identify significant risk factors for development of postoperative CSF leak. Results  There were 100 patients with extrasellar tumors who developed intraoperative CSF leaks. Seventeen patients (17%) developed postoperative CSF leaks. Leaks occurred at a median of 2 days following surgery (range 0-34 days). Clival tumors had a significantly higher incidence of postoperative leak than those in other sites ( p  < 0.05). There were no significant differences in other locations, body mass index, tumor size, reconstruction technique, medical comorbidities, or other factors. There were nearly twice as many intraoperative grade III leaks in those who developed postoperative CSF leak, but this was not statistically significant ( p  = 0.12). Conclusion  Extrasellar tumors, particularly clival tumors, have a higher rate of postoperative CSF leak than pituitary tumors. Prophylactic lumbar drains can be considered for patients at high risk for developing postoperative CSF leak.

Risk factors of cerebrospinal fluid leakage after neuroendoscopic transsphenoidal pituitary adenoma resection: a systematic review and meta-analysis

Introduction

Cerebro spinal fluid (CSF) leakage is common and might lead to severe postoperative complications after endoscopic transsphenoidal pituitary adenoma resection. However, the risk factors of postoperative CSF leakage are still controversial. This article presents a systematic review to explore the explicit risk factors of CSF leakage after endoscopic transsphenoidal pituitary adenomere section.

Methods

PRISMA and AMSTAR guidelines were followed to assess the methodological quality of the systematic review. PubMed, Medline, Embase, Web of Science, Cochrane, Clinical Trails, CNKI, CBM, Wan Fang, and VIP databases were searched for all studies on postoperative CSF leak risk factors. The quality of the included studies was assessed by the Newcastle-Ottawa scale. Review Manager 5.4 software was used to calculate the pooled effect size of potential factors with statistical significance.

Results

A total of 6775 patients with pituitary adenoma across 18 articles were included, containing 482 cases of postoperative CSF leakage (accounting for 7.11%). All of the articles had a quality score > 5, indicating good quality. Meta-analysis showed that an increased risk of CSF leak was found for higher levels of BMI (MD=1.91, 95% CI (0.86,2.96), bigger tumor size [OR=4.93, 95% CI (1.41,17.26)], greater tumor invasion (OR=3.01, 95% CI (1.71, 5.31), the harder texture of tumor [OR=2.65, 95% CI (1.95,3.62)], intraoperative cerebrospinal fluid leakage [OR=5.61, 95% CI (3.53,8.90)], multiple operations [OR=2.27, 95% CI (1.60,3.23)].

Conclusion

BMI, multiple operations, tumor size, tumor invasion, hard texture, and intraoperative cerebrospinal fluid leakage are the risk factors of postoperative CSF leakage. Clinical doctors should pay attention to these risk factors, and conduct strict skull base reconstruction and careful postoperative management.

[Endoscopic transnasal resection of clival meningiomas]

BACKGROUND

Surgical treatment of ventral and ventrolateral meningiomas of posterior cranial fossa is difficult in modern neurosurgery. This is due to peculiarities of approach to these areas and concentration of critical structures (cranial nerves and great vessels). Currently, endoscopic transnasal approach to these meningiomas allows partial, and in some cases, total resection. However, this technique is not widespread.

OBJECTIVE

To analyze the world literature data on postoperative outcomes in patients with clival and petroclival meningiomas after endoscopic transnasal resection.

MATERIAL AND METHODS

We analyzed 22 articles representing treatment of 61 patients with clival and petroclival meningiomas.

RESULTS

Total or near-total resection was achieved in 22.9% of cases, subtotal resection - 40.9%, partial resection - 26.2% (data were not provided in other cases). Even partial and subtotal resection leads to significant regression of symptoms.

CONCLUSION

Endoscopic transnasal surgery is a full-fledged alternative to transcranial approaches in surgical treatment of clival meningiomas. It is also an additional option for patients with petroclival meningiomas after ineffective transcranial approaches. Transnasal tumor shrinkage and devascularization lead to brainstem decompression, regression of hydrocephalus and baseline clinical symptoms.

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.

Endoscopic Endonasal Approach in Craniopharyngiomas: Representative Cases and Technical Nuances for the Young Neurosurgeon

Craniopharyngiomas (CPs) are Rathke's cleft-derived benign tumors originating most commonly in the dorsum sellae and representing 2% of intracranial neoplasms. CPs represent one of the more complex intracranial tumors due to their invasive nature, encasing neurovascular structures of the sellar and parasellar regions, making its resection a major challenge for the neurosurgeon with important postoperative morbidity. Nowadays, an endoscopic endonasal approach (EEA) provides an "easier" way for CPs resection allowing a direct route to the tumor with direct visualization of the surrounding structures, diminishing inadvertent injuries, and providing a better outcome for the patient. In this article, we include a comprehensive description of the EEA technique and nuances in CPs resection, including three illustrated clinical cases.

Fat in the Fossa and the Sphenoid Sinus: A Simple and Effective Solution to CSF Leaks in Transsphenoidal Surgery. Cohort Study and Systematic Review

Objectives  Cerebrospinal fluid (CSF) leak following endoscopic transsphenoidal surgery (TSS) remains a challenge and is associated with high morbidity. We perform a primary repair with f at in the pituitary f ossa and further fat in the s phenoid sinus (FFS). We compare the efficacy of this FFS technique with other repair methods and perform a systematic review. Design, Patients, and Methods  This is a retrospective analysis of patients undergoing standard TSS from 2009 to 2020, comparing the incidence of significant postoperative CSF rhinorrhea (requiring intervention) using the FFS technique compared with other intraoperative repair strategies. Systematic review of current repair methods described in the literature was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Results  In all, there were 439 patients, with 276 patients undergoing multilayer repair, 68 patients FFS repair, and 95 patients no repair. No significant differences were observed in baseline demographics between the groups. Postoperative CSF leak requiring intervention was significantly lower in the FFS repair group (4.4%) compared with the multilayer (20.3%) and no repair groups (12.6%, p  < 0.01). This translated to fewer reoperations (2.9% FFS vs. 13.4% multilayer vs. 8.4% no repair, p  < 0.05), fewer lumbar drains (2.9% FFS vs. 15.6% multilayer vs. 5.3% no repair, p  < 0.01), and shorter hospital stay (median days: 4 [3-7] FFS vs. 6 (5-10) multilayer vs. 5 (3-7) no repair, p  < 0.01). Risk factors for postoperative leak included female gender, perioperative lumbar drain, and intraoperative leak. Conclusion  Autologous fat on fat graft for standard endoscopic transsphenoidal approach effectively reduces the risk of significant postoperative CSF leak with reduced reoperation and shorter hospital stay.

Machine learning driven prediction of cerebrospinal fluid rhinorrhoea following endonasal skull base surgery: A multicentre prospective observational study

Background

Cerebrospinal fluid rhinorrhoea (CSFR) is a common complication following endonasal skull base surgery, a technique that is fundamental to the treatment of pituitary adenomas and many other skull base tumours. The CRANIAL study explored CSFR incidence and related risk factors, particularly skull base repair techniques, via a multicentre prospective observational study. We sought to use machine learning to leverage this complex multicentre dataset for CSFR prediction and risk factor analysis.

Methods

A dataset of 865 cases - 725 transsphenoidal approach (TSA) and 140 expanded endonasal approach (EEA) - with cerebrospinal fluid rhinorrhoea as the primary outcome, was used. Relevant variables were extracted from the data, and prediction variables were divided into two categories, preoperative risk factors; and repair techniques, with 6 and 11 variables respectively. Three types of machine learning models were developed in order to predict CSFR: logistic regression (LR); decision tree (DT); and neural network (NN). Models were validated using 5-fold cross-validation, compared via their area under the curve (AUC) evaluation metric, and key prediction variables were identified using their Shapley additive explanations (SHAP) score.

Results

CSFR rates were 3.9% (28/725) for the transsphenoidal approach and 7.1% (10/140) for the expanded endonasal approach. NNs outperformed LR and DT for CSFR prediction, with a mean AUC of 0.80 (0.70-0.90) for TSA and 0.78 (0.60-0.96) for EEA, when all risk factor and intraoperative repair data were integrated into the model. The presence of intraoperative CSF leak was the most prominent risk factor for CSFR. Elevated BMI and revision surgery were also associated with CSFR for the transsphenoidal approach. CSF diversion and gasket sealing appear to be strong predictors of the absence of CSFR for both approaches.

Conclusion

Neural networks are effective at predicting CSFR and uncovering key CSFR predictors in patients following endonasal skull base surgery, outperforming traditional statistical methods. These models will be improved further with larger and more granular datasets, improved NN architecture, and external validation. In the future, such predictive models could be used to assist surgical decision-making and support more individualised patient counselling.

Factors Predicting Cerebrospinal Fluid Leaks in Microvascular Decompressions: A Case Series of 1011 Patients

BACKGROUND

Microvascular decompression (MVD) using a retrosigmoid approach is a highly effective, open-surgical procedure for neurovascular conflict in the posterior fossa, although there is a risk of postoperative cerebrospinal fluid (CSF) leak.

OBJECTIVE

To identify factors associated with postoperative CSF leakage after MVD.

METHODS

We retrospectively reviewed all patients who underwent MVDs at our institution from 2007 to 2020. Patient demographics, clinical diagnoses, and procedural characteristics were recorded and compared. Factors leading to CSF leak were analyzed using χ 2 , univariate, and multivariate regression.

RESULTS

Of 1011 patients who underwent MVDs, 37 (3.7%) presented with postoperative CSF leaks. In univariate analysis, the use of Cranios/Norian to obliterate the air cells was protective against CSF leak ( P = .01). Craniotomies ( P = .002), the use of dural substitutes such as Durepair ( P = .04), dural onlays such as DuraGen ( P = .04), muscle/fascia ( P = .03), and titanium mesh cranioplasty >5 cm ( P = .03) were associated with CSF leak. On multivariate analysis, only the presence of craniotomies ( P = .04) and nonprimary dural closure ( P = .03) were significant risk factors for CSF leak. When excluding the 34 (3.4%) patients who underwent a craniotomy, the lack of primary dural closure still remained significantly associated with postoperative CSF leak ( P = .04).

CONCLUSION

Our results represent one of the largest series of posterior fossa surgeries for a uniform indication in North America. Our study demonstrates increased risk for postoperative CSF leak when craniotomies are performed and when primary dural closure is not established. Given the small sample of patients who received a craniotomy, however, future studies corroborating this finding should be performed.

Remission, complications, and overall survival in transsphenoidal pituitary surgery-a Swedish single-center experience of 578 patients

BACKGROUND

Surgical treatment of pituitary lesions causing hormonal overproduction or mass effect is standard procedure. There are few reports on the results and complications related to these surgeries from Northern Europe. Our aim was to evaluate the outcome and complications of a single tertiary surgical center over more than a decade.

METHODS

This was a retrospective study on all patients that underwent pituitary surgery from 1st of January 2005 to 31st of December 2017. The analysis included type of lesion, surgical method, pre- and postoperative need for hormonal substitution, hormonal outcome, complications to surgery, survival, need for revision surgery, or stereotactic radiation. Appropriate statistical analyses were made to evaluate surgical results, complications, and survival.

RESULTS

Five hundred seventy-eight patients were included in the study. Remission was achieved in 58% of patients with GH-producing and 94% of ACTH-releasing adenomas. Sixty-six percent had no preoperative hormonal substitution compared to 39% postoperatively. Rhinosinusitis (10%) was the most commonly reported postoperative complication followed by leakage of cerebrospinal fluid (8%) and meningitis (4%). Standardized mortality rate for the study population was higher (p = 0.18) when compared to the general population.

CONCLUSION

Our results regarding remission rates and complications are in comparison with previous studies. Surgery of pituitary lesion can be considered a safe and efficient surgery. We noted lower rates of CSF leakage in the later part of the study period and believe that this, in part, was an effect by the introduction of a multidisciplinary surgical skull base team and increased surgical experience.

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.

Application of dural suturing in the endoscopic endonasal approach to the sellar region

Objectives

The endoscopic endonasal approach (EEA) is widely used in the treatment of cranial base tumors. Skull base reconstruction is a crucial part of EEA, which has a great impact on patients’ prognosis. In this study, we report our experience with sellar dural suturing in cranial base reconstruction and retrospectively analyze its effect.

Methods

The clinical data of 134 patients who suffered intraoperative CSF leakage and underwent EEA surgery in the Department of Neurosurgery of the First Affiliated Hospital of Nanjing Medical University from October 2018 to November 2020 were retrospectively collected and analyzed. According to whether sellar dural suturing was performed during the operation, they were divided into a suture group (55 cases) and a control group (79 cases).

Results

The results showed that dural suturing of the sellar floor effectively reduced the postoperative hospitalization duration (p = 0.026) and the use rates of lumbar drainage (p = 0.047), autologous fat transplantation (p = 0.038), and pedicled nasoseptal flaps (p = 0.026).

Conclusion

Sellar dural suturing under endoscopy is a promising and effective method for cranial base reconstruction in EEA surgery and is worthy of clinical application.

Factors Influencing Cerebrospinal Fluid Leaking following Pituitary Adenoma Transsphenoidal Surgery: A Meta-Analysis and Comprehensive Review

Background

Surgical resection is the main method to treat pituitary adenoma. Cerebrospinal fluid leakage (CSF Leak) is the main complication after transsphenoidal surgery. The impact of postoperative CSF Leak can be predicted in advance, and preventive measures can be taken in time. Clinically, a variety of factors may affect the occurrence of postoperative CSF Leak. In this study, meta-analysis was used to investigate the risk factors of postoperative CSF Leak as a clinical reference.

Methods

The databases PubMed, Medline, Embrase, Cochrane library, CNKI, and CBM were searched for all studies on the risk factors of postoperative CSF Leak. Studies were screened and finally included. The quality of the included studies was assessed by the Newcastle-Ottawa scale. We used Revman 5.4 software to conduct the pooled effect size of every potential statistically significant factor.

Results

13 articles with a total of 5967 patients with pituitary adenoma and 405 cases of postoperative CSF Leak were finally included, accounting for 6.79%. All of the 13 articles had a quality score > 5, indicating good quality. Meta-analysis showed that patient age (OR = 0.71, 95% CI (0.41, 1.20), P = 0.20) was not a factor influencing postoperative CSF Leak, while BMI (MD = 2.26, 95% CI (1.31, 3.20), P < 0.00001), tumor size (MD = 1.35, 95% CI (0.22, 2.49), P = 0.02), whether a second operation was performed (OR = 2.20, 95% CI (1.45, 3.33), P = 0.0002), and intraoperative CSF Leak (OR = 8.88, 95% CI (3.64, 21.69), P < 0.00001) were risk factors for postoperative CSF Leak in patients. Discussion. BMI, tumor size, reoperation, and intraoperative CSF Leak are the risk factors of postoperative CSF Leak. However, not all the factors were covered in this study, it is still worth continuing to deeply investigate in this topic.

Sinonasal outcomes associated with the use of BioGlue® in endoscopic transsphenoidal pituitary surgery

Concerns have been raised in the neurosurgical literature regarding the use of BioGlue®, a tissue sealant initially developed for cardiothoracic surgery, due to reports of an increased incidence of infection, wound breakdown, and CSF fistulae. The aim of this study was to determine if the use of BioGlue® in skull base repair impacts on the sinonasal outcomes and the incidence of post-operative infection following endoscopic pituitary surgery. SNOT-22 questionnaires were completed pre-operatively, and at 6, 12, and 24 weeks post-operatively by 50 patients. Pre- and post-operative MRI scans were reviewed and assessed for evidence of post-operative sinusitis. Patient records were consulted to ascertain the incidence of post-operative infection. Repeated measures ANOVA and Wilcoxon signed rank test were used for data analysis. Statistical analysis revealed a significant difference in the mean SNOT-22 scores across the four time intervals (F(1.605, 78.642) = 9.180, p = 0.001). This difference was powered by a deterioration at 6 weeks that recovered completely by 12 weeks. The mean SNOT-22 score in the study cohort at 24 weeks was 16.84/110 (range 0-57, ± 2.04) which was lower than the mean pre-operative score and is consistent with mild rhinosinusitis. There were no cases of post-operative meningitis and 1/50 (2%) case of post-operative sinusitis in this cohort. The use of BioGlue® in endoscopic endonasal pituitary surgery does not appear to lead to significant sinonasal morbidity. Previous concerns about the use of BioGlue® in transcranial procedures may not apply to extradural application of this tissue sealant in endoscopic transnasal surgery.

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

OBJECTIVE

Sellar reconstruction following endoscopic endonasal surgery (EES) requires modification based on the degree of cerebrospinal fluid (CSF) leak. For high-flow (grade II or III according to Esposito et al. 2007) intraoperative CSF leak, lumbar drainage (LD), in addition to the multilayer closing technique, is generally recommended. However, LD occasionally has complications including postpuncture headache, overdrainage symptoms, and increased length of stay. We retrospectively evaluated the outcome of our graded reconstruction strategy using a multilayer technique with a novel material, without LD, after EES.

METHODS

Ninety-seven patients who underwent EES with grade II or III intraoperative CSF leak between June 2020 and March 2021 were retrospectively reviewed. For grade II CSF leak, fibrin sealant and a nasoseptal flap were placed; for grade III CSF leak, a multilayer technique was used in combination with collagen matrix, an acellular dermal graft, injectable hydroxyapatite (HXA), and a nasoseptal flap. Postoperatively, routine LD was not performed.

RESULTS

This study included 48 (49.5%) grade II and 49 (50.5%) grade III CSF leaks. At follow-up (mean, 8.7 months), no patient showed postoperative CSF leak in either group. No HXA-associated complications occurred.

CONCLUSIONS

A graded surgical repair strategy after EES could avoid postoperative CSF leak. Combined use of injectable HXA and acellular dermal grafts for high-flow CSF leak can limit LD requirement without significant risks.

Transnasal transsphenoidal pituitary surgery in a large tertiary hospital, a retrospective study

OBJECTIVES

Pituitary adenomas (PAs), although being small tumours, can have quite an impact on patients' lives causing hormonal and visual disturbances, for which surgery must be performed. As a large peripheral hospital with specialists in pituitary surgery, an assessment of the efficacy and safety of transnasal transsphenoidal pituitary surgery was made.

METHODS

A retrospective analysis of neurosurgical reports as well as pre and postoperative imaging was made to evaluate the presenting symptoms, tumoural variables, peri-operative morbidity, and long-term outcome.

RESULTS

This cohort included 105 patients who were operated for PAs over a 9-year period, with a slight male predominance. Adenomas had a mean maximum diameter of almost 25 mm, with one-third of tumours presenting with a Knosp-grade 3 or 4. As expected, most patients presented with either visual (32.4%) or hormonal (40.0%) disturbances. After surgery, 85.3% had complete resolution of visual deficits, and 97.1% had normalisation of hormonal hypersecretion. Postoperative hormonal insufficiency requiring substitution was observed in 43.1% and was significantly more frequent in males and in non-functioning pituitary adenomas (NFAs). Postoperative cerebrospinal fluid (CSF) leakage was observed in 2.9%, and merely one patient developed meningitis. Tumour recurrence was significantly more frequent in patients with partial resection as compared to complete resection (25.6 vs. 7.9%).

CONCLUSIONS

This study demonstrates that transnasal transsphenoidal pituitary surgery can be performed safely and effectively in a large non-university hospital, improving visual and/or hormonal disturbances as well as providing long-term tumour control. Patients with larger adenomas are at an increased risk to develop postoperative hypopituitarism.

Skull base repair following endonasal pituitary and skull base tumour resection: a systematic review

PURPOSE

Postoperative cerebrospinal fluid rhinorrhoea (CSFR) remains a frequent complication of endonasal approaches to pituitary and skull base tumours. Watertight skull base reconstruction is important in preventing CSFR. We sought to systematically review the current literature of available skull base repair techniques.

METHODS

Pubmed and Embase databases were searched for studies (2000-2020) that (a) reported on the endonasal resection of pituitary and skull base tumours, (b) focussed on skull base repair techniques and/or postoperative CSFR risk factors, and (c) included CSFR data. Roles, advantages and disadvantages of each repair method were detailed. Random-effects meta-analyses were performed where possible.

RESULTS

193 studies were included. Repair methods were categorised based on function and anatomical level. There was absolute heterogeneity in repair methods used, with no independent studies sharing the same repair protocol. Techniques most commonly used for low CSFR risk cases were fat grafts, fascia lata grafts and synthetic grafts. For cases with higher CSFR risk, multilayer regimes were utilized with vascularized flaps, gasket sealing and lumbar drains. Lumbar drain use for high CSFR risk cases was supported by a randomised study (Oxford CEBM: Grade B recommendation), but otherwise there was limited high-level evidence. Pooled CSFR incidence by approach was 3.7% (CI 3-4.5%) for transsphenoidal, 9% (CI 7.2-11.3%) for expanded endonasal, and 5.3% (CI 3.4-7%) for studies describing both. Further meaningful meta-analyses of repair methods were not performed due to significant repair protocol heterogeneity.

CONCLUSIONS

Modern reconstructive protocols are heterogeneous and there is limited evidence to suggest the optimal repair technique after pituitary and skull base tumour resection. Further studies are needed to guide practice.

Evaluation of the Gross Total Resection Rate of Suprasellar Pituitary Macroadenomas with and without the Removal of the Tuberculum Sellae Bone

OBJECTIVE

Improving the gross total resection (GTR) rate of suprasellar pituitary macroadenomas (SPMAs) using the pure endoscopic endonasal transsphenoidal approach (EETA) has been a long-standing focus of neurosurgeons. This study was aimed at evaluating the influences of the removal of the tuberculum sellae bone (TSB) without opening the dura of the tuberculum sellae on the GTR rate of SPMAs via the EETA.

METHODS

We retrospectively analyzed medical reports of patients with SPMAs who underwent EETA between February 2015 and November 2020. Data on clinical manifestations, endocrinologic types, imaging features (Hardy classification, morphology, and texture), clinical outcomes, and TSB removal status were collected. All patients were followed up for 6 months postoperatively.

RESULTS

Seventy-eight patients were enrolled in our study. The GTR rates of the TSB removal group (45/78, 57.7%) and nonremoval group (33/78, 42.3%) were 80.0% (36/45) and 57.6% (19/33), respectively. Univariate logistic regression analysis found that the removal of TSB, rounded morphology, and low Hardy classification were correlated with higher GTR rates. Multiple logistic regression analysis indicated that even after adjusting for tumor types and imaging features, the removal of TSB had an independent effect on the GTR rate (odds ratio, 7.6; 95% confidence interval, 1.8-31.6; P = 0.005). The incidence rates of postoperative cerebrospinal fluid leakage and diabetes insipidus were not significantly different between the TSB removal group and TSB nonremoval group.

CONCLUSIONS

TSB removal using EETA without opening the tuberculum sellae dura improves the GTR rate of SPMAs without increasing the incidence of postoperative complications.

The incidence of postoperative cerebrospinal fluid leakage after elective cranial surgery: a systematic review

Cerebrospinal fluid (CSF) leakage is a major complication after elective neurosurgical procedures. The aim of this systematic literature review is to summarize the incidence rates of postoperative cerebrospinal fluid leakage for neurosurgical procedures, classified by surgical approach. The Pubmed, Cochrane, Embase, and Web of Science databases were searched for studies reporting the outcome of patients undergoing elective neurosurgical procedures. The number of patients, surgical approach, and indication for surgery were recorded for each study. Outcomes related to CSF leakage such as clinical manifestation and treatment were reported as well. One hundred and thirteen studies were included, reporting 94,695 cases. Overall, CSF leaks were present in 3.8% of cases. Skull base surgery had the highest rate of CSF leakage with 6.2%. CSF leakage occurred in 5.9% of anterior skull base procedures, 6.4% of middle fossa, and 5.2% of transpetrosal surgeries. 5.8% of reported infratentorial procedures were complicated by CSF leakage versus 2.9% of supratentorial surgeries. CSF leakage remains a common serious adverse event after cranial surgery. There exists a need for standardized procedures to reduce the incidence of postoperative CSF leakage, as this serious adverse event may lead to increased health care costs.

Perioperative Complications in Endoscopic Endonasal versus Transcranial Resections of Adult Craniopharyngiomas

BACKGROUND

Adult craniopharyngiomas are low-grade tumors of the pituitary infundibulum that can be locally aggressive and frequently present with profound visual deficits and endocrinopathies. Surgical resection remains the preferred initial treatment for these lesions, and recently endoscopic endonasal approaches (EEAs) have become increasingly used. However, minimal data exist comparing these techniques with traditional transcranial (TC) methods. The purpose of this study was to evaluate perioperative differences in EEA and TC approaches for adult craniopharyngiomas over the past several decades.

METHODS

Craniopharyngioma surgeries in the Nationwide Inpatient Sample from 1998 to 2014 were identified. Complication rates, mortality rates, and annual treatment trends were stratified by procedure. Annual caseload was assessed with linear regression, and multivariate logistic regression models were created to determine predictors of inpatient mortality and perioperative complications.

RESULTS

From 1998-2014, a significant increase in EEAs for craniopharyngiomas (+4.36/year, r² = 0.80, P < 0.0001) was observed. In contrast, no increase in TC surgeries for these lesions was seen. In multivariate analysis, EEAs were more likely to experience postoperative cerebrospinal fluid leak (odds ratio = 2.61, P < 0.0001). However, EEAs were protective against all other perioperative complications including diabetes insipidus, panhypopituitarism, visual impairment, and even mortality (odds ratio = 0.41, P = 0.0007).

CONCLUSIONS

Over the past several decades, utilization of EEAs to resect adult craniopharyngiomas has increased. EEAs appear to be associated with lower rates of perioperative mortality and complications. However, long-term, prospective studies controlling for tumor size, location, and preoperative symptomatology are needed to determine when one approach should be used preferentially over the other.

Endoscopic extended transsphenoidal surgery for newly diagnosed paediatric craniopharyngiomas

PURPOSE

Endoscopic extended transsphenoidal surgery (EETSS) has gained popularity for treatment of craniopharyngiomas. The aim of this study is to assess the outcome of endoscopic extended transsphenoidal surgery (EETSS) for newly diagnosed paediatric craniopharyngiomas.

METHODS

Patient details were obtained from a prospective database of all endoscopic transnasal operations performed by a single surgeon. Outcomes including visual function, pituitary function, body mass index (BMI), postoperative neurological deficit, extent of resection and recurrence on follow-up were obtained. Obesity was defined as BMI percentile of equal to or greater than 95%.

RESULTS

Between January 2011 and January 2020, 15 of 16 children (5-18 years old) with newly diagnosed craniopharyngiomas underwent EETSS. Four patients had a conchal-type sphenoid sinus. Gross total resection (GTR) was achieved in 4 patients and near total resection (NTR) in 5 patients. The remaining 6 had subtotal resection (STR). Postoperative radiotherapy was used in 6 patients (4 with STR, 2 with NTR). There were no postoperative deaths, strokes or CSF leaks. Normalisation of visual fields (VF) occurred in 9/13 patients with preoperative VF defects. One patient developed a new visual field defect. During a median follow-up period of 74 (8-104) months, 2 patients have required further surgery for tumour progression following initial STR, where a tumour remnant was left in situ to preserve the pituitary stalk. 6/11 patients developed new anterior pituitary dysfunction as a result of surgery and 9/12 developed new diabetes insipidus (DI). At the time of last follow-up, 14/15 children had anterior panhypopituitarism, 13/15 had DI and 1 patient developed new onset obesity. Two patients, who were obese preoperatively, were no longer obese at last follow-up.

CONCLUSIONS

EETSS can be performed as the first option in the majority of children with newly diagnosed craniopharyngioma, despite factors such as small nose, non-pneumatised sphenoid sinus, small sella or purely suprasellar tumour location. Preservation of the pituitary stalk at the expense of leaving residual tumour may not be in the best interests of the patient.

CSF Rhinorrhoea After Endonasal Intervention to the Skull Base (CRANIAL) - Part 1: Multicenter Pilot Study

Background

CRANIAL (CSF Rhinorrhoea After Endonasal Intervention to the Skull Base) is a prospective multicenter observational study seeking to determine 1) the scope of skull base repair methods used and 2) corresponding rates of postoperative cerebrospinal fluid (CSF) rhinorrhea in the endonasal transsphenoidal approach (TSA) and the expanded endonasal approach (EEA) for skull base tumors. We sought to pilot the project, assessing the feasibility and acceptability by gathering preliminary data.

Methods

A prospective observational cohort study was piloted at 12 tertiary neurosurgical units in the United Kingdom. Feedback regarding project positives and challenges were qualitatively analyzed.

Results

A total of 187 cases were included: 159 TSA (85%) and 28 EEA (15%). The most common diseases included pituitary adenomas (n = 142/187), craniopharyngiomas (n = 13/187). and skull base meningiomas (n = 4/187). The most common skull base repair techniques used were tissue glues (n = 132/187, most commonly Tisseel), grafts (n = 94/187, most commonly fat autograft or Spongostan) and vascularized flaps (n = 51/187, most commonly nasoseptal). These repairs were most frequently supported by nasal packs (n = 125/187) and lumbar drains (n = 20/187). Biochemically confirmed CSF rhinorrhea occurred in 6/159 patients undergoing TSA (3.8%) and 2/28 patients undergoing EEA (7.1%). Four patients undergoing TSA (2.5%) and 2 patients undergoing EEA (7.1%) required operative management for CSF rhinorrhea (CSF diversion or direct repair). Qualitative feedback was largely positive (themes included user-friendly and efficient data collection and strong support from senior team members), demonstrating acceptability.

Conclusions

Our pilot experience highlights the acceptability and feasibility of CRANIAL. There is a precedent for multicenter dissemination of this project, to establish a benchmark of contemporary practice in skull base neurosurgery, particularly with respect to patients undergoing EEA.

Methods of Skull Base Repair Following Endoscopic Endonasal Tumor Resection: A Review

Following the introduction of fully endoscopic techniques for the resection of pituitary tumors, there was a rapid expansion of the indications for endonasal endoscopic surgery to include extrasellar tumors of the skull base. These techniques offer significant advantages over traditional open surgical approaches to the skull base, including improved tumor resection, and better post-operative neurological outcomes. Following their introduction, however, the initial rate of post-operative CSF leak was unacceptably high. Post-operative CSF leak following skull base surgery is a major source of morbidity, and can lead to the development of life-threatening intracranial infection. The use of vascularized naso-septal flaps transformed the management of these patients, significantly reducing the rate of post-operative CSF leak and increasing the number of patients that could benefit from this less invasive treatment modality. Adequate repair of iatrogenic defects in the skull base is of crucial importance for patients with skull base tumors, as the development of a post-operative CSF leak, and the associated complications can significantly delay the administration of the adjunctive oncological therapies these patients require. In this review, we provide an overview of the latest evidence regarding skull base reconstruction following endoscopic skull base surgery, and describe the skull base repair technique in use at our institution.