Factors impacting cerebrospinal fluid leak rates in endoscopic sellar surgery

Utilization of Polydioxanone Plate for Endoscopic Anterior Skull Base Repair: Operative Technique and Long-Term Cohort Outcomes

Objective  The purpose of this study is to report the technical procedure and our experience using a polydioxanone suture (PDS) plate with dural substitute as part of a fully resorbable gasket seal technique to repair anterior skull base defects. Methods  A series of patients undergoing anterior skull base reconstruction utilizing our resorbable gasket seal technique from January 2014 to July 2022 was reviewed. Results  A total of 155 patients were included. Nine (5.8%) of the included patients developed postoperative cerebrospinal fluid (CSF) leaks requiring reoperation. There were no cases of intraoperative cranial nerve injury or internal carotid artery injury. A total of 103 (66.5%) patients were observed to have an intraoperative CSF leak, including 57 low-flow leaks and 46 high-flow leaks; 1 of 57 (1.8%) patients with low-flow leaks and 8 of 46 (17.4%) patients with high-flow leaks developed a postoperative CSF leak. During the first 3 years that this technique was utilized at our center for the management of high-flow intraoperative CSF leaks, postoperative CSF leaks were documented in 4 of 12 (33.3%) patients, in comparison to 4 of 34 (11.8%) in the following years. Conclusion  PDS plate reconstruction confers several advantages and can be used in a diverse set of operative scenarios in conjunction with other reconstruction options. There appeared to be an associated learning curve as surgeons at our center gained experience with this new technique. Our findings show that the PDS plate reconstruction is safe and effective in repairing the skull base.

Complications following endoscopic transsphenoidal surgery for pituitary adenoma-special focus on intrasellar pressure

PURPOSE

The aim of this study was to explore risk factors for intraoperative events and postoperative complications of endoscopic transsphenoidal surgery (ETS) for pituitary tumors, and the role of intrasellar pressure (ISP) in relation to complications.

METHODS

The study was a single-center, retrospective, consecutive, observational study, with ISP data collected prospectively. After exclusions, the study population encompassed 69 patients. All had ISP measured intraoperatively during ETS for a pituitary adenoma and underwent standardized postoperative observations and follow-up. Data on complications within 3 months after surgery and some risk factors were collected retrospectively.

RESULTS

Decreased risk of postoperative cerebrospinal fluid leakage was seen with higher age. Large tumor volume was associated with higher risk of intraoperative events. ISP was not associated with complication frequency, but patients with ISP > 20 mmHg had increased frequency of postoperative epistaxis.

CONCLUSION

This study confirms earlier findings of low age as a possible risk factor for postoperative cerebrospinal fluid leakage. Tumor volume is suggested to be associated with higher complication risk. ISP does not seem to be a significant risk factor for intraoperative events or postoperative complications following ETS. Predictive risk factors for surgical complications after ETS are still not satisfactorily explained and heterogeneous definitions of complications are problematic in this context.

Analysis of Risk Factors and Development of a Prediction Model for Intraoperative Cerebrospinal Fluid Leakage During Transsphenoidal Pituitary Adenoma Surgery

OBJECTIVE

Cerebrospinal fluid (CSF) leakage may occur during transsphenoidal resection of pituitary adenomas, with implications for patient prognosis. However, although the risk factors for intraoperative CSF leakage have been widely studied and continuously explored, there are still some unknown factors that play a role.

METHODS

A retrospective study was conducted by collecting clinical data from 281 patients who underwent transsphenoidal resection of pituitary adenoma at Nanjing Drum Tower Hospital between October 2020 and October 2022.

RESULTS

The results showed CSF leakage occurred in 60 (21.4%) patients. In the univariate analysis, we found that tumor anteroposterior diameter (p = 0.024), hepatic insufficiency (p = 0.004), tough tumor texture (p < 0.001), and surgical protocol as complete removal (p = 0.01) significantly predicted the occurrence of CSF leakage. In the univariate analysis, we found that anteroposterior diameter was associated with the occurrence of intraoperative CSF leakage compared with another diameter (p = 0.04), indicating that the probability of CSF leakage significantly increased at the anteroposterior diameter of pituitary adenoma ≥2 cm. We included anteroposterior tumor diameter, hepatic insufficiency, complete removal, and tumor tough texture together in a multifactorial logistic regression analysis and produced a nomogram graph based on the results. In the multifactorial logistic regression analysis, the anteroposterior tumor diameter, tumor tough texture, hepatic insufficiency, and the surgical option of complete removal predicted intraoperative CSF leakage with an AUC of 0.804.

CONCLUSIONS

This provides a reference for assessing the risk of CSF leakage in patients before and early in the surgical procedure and may have clinical implications for better patient treatments.

Development and validation of a nomogram for predicting cerebrospinal fluid leak after endoscopic craniopharyngioma resection

OBJECTIVE

To identify risk factors for cerebrospinal fluid (CSF) leak after extended endoscopic endonasal surgery for craniopharyngiomas and develop a predictive model for predicting postoperative CSF leak.

METHODS

Six hundred and sixty cases of craniopharyngioma (training cohort: n = 462; validation cohort: n = 198) were retrospectively reviewed between October 2018 and May 2024, and relevant risk factors were identified. A nomogram was built using a stepwise logistic regression method based on the Akaike information criterion. The performance of the nomogram was evaluated using area under the curve (AUC), calibration curve, and decision curve analysis.

RESULTS

The overall rate of postoperative CSF leak was 4.5%. Higher prognostic nutritional index (PNI) level (OR 0.819, 95% confidence interval [CI] 0.735-0.912; p < 0.001) and larger dural defect (OR 6.789, 95% CI 3.112-14.807; p < 0.001) were identified as independent predictors for postoperative CSF leak in multivariable logistic regression analysis. The AUCs of the nomogram were 0.870 (95% CI, 0.782-0.957; p < 0.001) and 0.842 (95% CI, 0.722-0.963; p < 0.001) in the training and validation sets, respectively. Calibration curves in the training and validation cohorts showed satisfactory agreement between predictive and actual outcomes (p = 0.608 and p = 0.564, respectively). Decision curve analysis further confirmed the clinical usefulness of the nomogram.

CONCLUSIONS

Higher PNI levels may help reduce the risk of postoperative CSF leak, while a larger dural defect size was demonstrated as an independent risk factor. We developed and validated a nomogram for predicting CSF leak after endoscopic craniopharyngioma resection, which showed strong predictive performance and could assist clinicians in formulating personalized treatment strategies.

Clinical Application of Artificial Intelligence in Prediction of Intraoperative Cerebrospinal Fluid Leakage in Pituitary Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Postoperative cerebrospinal fluid (CSF) leakage is the leading adverse event in transsphenoidal surgery. Intraoperative CSF (ioCSF) leakage is one of the most important predictive factors for postoperative CSF leakage. This systematic review and meta-analysis aimed to evaluate the effectiveness of artificial intelligence (AI) models in predicting ioCSF.

METHODS

Literature records were retrieved on June 13, 2024, using the relevant key terms without filters in PubMed, Embase, Scopus, and Web of Science. Records were screened according to the eligibility criteria, and the data from the included studies were extracted. The quality assessment was performed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The meta-analysis, sensitivity analysis, and meta-regression were conducted using R software.

RESULTS

Our results demonstrate that the AI models achieved a pooled sensitivity of 93.4% (95% confidence interval [CI]: 74.8%-98.6%) and specificity of 91.7% (95% CI: 75%-97.6%). The subgroup analysis revealed that the pooled sensitivities in machine learning and deep learning were 86.2% (95% CI: 83%-88.8%) and 99% (95% CI: 93%-99%), respectively (P < 0.01). The subgroup analysis demonstrated a pooled specificity of 92.1% (95% CI: 63.1%-98.7%) for machine learning and 90.6% (95% CI: 78.2%-96.3%) for deep learning models (P = 0.87). The diagnostic odds ratio meta-analysis revealed an odds ratio 114.6 (95% CI: 17.6-750.9). The summary receiver operating characteristic curve demonstrated that the overall area under the curve of the studies was 0.955, which is a considerable performance.

CONCLUSIONS

AI models have demonstrated promising performance for predicting the ioCSF leakage in pituitary surgery and can optimize the treatment strategy.

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.

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.

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.

Defining benchmark outcomes for transsphenoidal surgery of pituitary adenomas: a multicenter analysis

IMPORTANCE

Benchmarks aid in improve outcomes for surgical procedures. However, best achievable results that have been validated internationally for transsphenoidal surgery (TS) are not available.

OBJECTIVE

We aimed to establish standardized outcome benchmarks for TS of pituitary adenomas.

DESIGN

A total of 2685 transsphenoidal tumor resections from 9 expert centers in 3 continents were analyzed.

SETTING

Patients were risk stratified, and the median values of each center's outcomes were established. The benchmark was defined as the 75th percentile of all median values for a particular outcome. The postoperative benchmark outcomes included surgical factors, endocrinology-specific values, and neurology-specific values.

RESULTS

Of 2685 patients, 1149 (42.8%) defined the low-risk benchmark cohort. Within these benchmark cases, 831 (72.3%) patients underwent microscopic TS, and 308 (26.8%) patients underwent endoscopic endonasal resection. Of all tumors, 799 (29.8%) cases invaded the cavernous sinus. The postoperative complication rate was 19.6% with mortality between 0.0% and 0.8%. Benchmark cutoffs were ≤2.9% for reoperation rate, ≤1.9% for cerebrospinal fluid leak requiring intervention, and ≤15.5% for transient diabetes insipidus. At 6 months, benchmark cutoffs were calculated as follows: readmission rate: ≤6.9%, new hypopituitarism ≤6.0%, and tumor remnant ≤19.2%.

CONCLUSIONS

This analysis defines benchmark values for TS targeting morbidity and mortality and represents the best outcomes in the best patients in expert centers. These cutoffs can be used to assess different centers, patient populations, and novel surgical techniques. It should be noted that the benchmark values may influence each other and must be evaluated in their own context.

Reducing CSF complications by a recycled Hadad's flap combined with autologous mucosa in secondary endoscope transsphenoidal surgery

Background

Transsphenoidal secondary operations are a minority but not a rare occurrence. How to viably prevent cerebral fluid (CSF)-related complications and confine surgery-caused injury in secondary surgery as minimally as possible is a huge challenge. This article shares our solution of recycling a prior Hadad-Bassagasteguy flap (HBF) along with a using small piece of free autologous mucosa to reconstruct the skull base.

Methods

Of 69 patients, fitted criteria were assigned into 2 different groups: a recycled HBF incorporated with an autologous free mucosa and a recycled HBF incorporated with an artificial dura to rebuild the skull base in secondary transsphenoidal surgery. The postoperative morbidities of pseudomeningocele, CSF leakage and meningitis were recorded and analyzed.

Results

A recycled HBF incorporated with an autologous mucosa is capable of reducing CSF complications compared to that of the matched group, particularly decreasing the morbidity of meningitis in secondary transsphenoidal surgery. Diabetes mellitus, craniopharyngioma, chordoma and the utilization of artificial dura were independent risk factors for CSF complications in secondary transsphenoidal surgery through univariate and multivariate logistic regression. In addition, diabetes mellitus and artificial dura are more likely to induce CSF leakage and meningitis. Patients suffering from craniopharyngioma are more susceptible to meningitis. Chordoma indiscriminately increased the risk of each CSF complication.

Conclusion

A recycled HBF incorporated with an autologous mucosa is reliable for reconstructing the skull base in secondary transsphenoidal surgery, especially for patients simultaneously suffering from diabetes mellitus and central skull base tumors.

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.

Two- and three-dimensional endoscopic endonasal surgery of large and giant pituitary adenomas-outcome analysis of a series of 62 patients from a single pituitary center

To analyze the perioperative course and clinical outcome of patients with large (lPA) and giant (gPA) pituitary adenoma who underwent endoscopic endonasal transsphenoidal surgery (EETS) using either two-dimensional (2D-E) or three-dimensional (3D-E) endoscopic systems. Single-center retrospective study of consecutive patients with lPA and gPA who underwent EETS between November 2008 and January 2023. LPA were defined as ≥ 3 cm and < 4 cm in diameter in at least one dimension and a volume of ≥ 10ccm; gPA were defined as larger than 4 cm in diameter and with a greater volume than 10ccm. Patient data (age, sex, endocrinological and ophthalmological status) and tumor data (histology, tumor volume, size, shape, cavernous sinus invasion according to the Knosp classification) were analyzed. 62 patients underwent EETS. 43 patients were treated for lPA (69.4%) and 19 patients for gPA (30.6%). 46 patients (74.2%) underwent surgical resection using 3D-E and 16 patients 2D endoscopy (25.8%). Statistical results are referred to the comparison between 3D-E and 2D-E. Patients' age ranged from 23-88 years (median 57), 16 patients were female (25.8%), 46 male (74.2%). Complete tumor resection was possible in 43.5% (27/62), partial resection in 56.5% (35/62). Resection rates did not differ between 3D-E (27 patients [43.5%]) and 2D-E (7 patients [43.8%], (p = 0.985). Visual acuity improved in 30 of 46 patients with preoperative deficit (65.2%). In the 3D-E group 21 of 32 patients (65.7%) improved, compared to 9 of 14 patients in the 2D-E group (64.3%). Improvement of visual field was achieved in 31 of 50 patients (62.0%; 22 of 37 patients in the 3D-E group [59.4%] and 9 of 13 patients in the 2D-E group [69.2%]). CSF leak was the most frequent complication and occurred in 9 patients (14.5%, [8 patients 17.4% 3D-E]) without statistical significance. Other surgical complications like postoperative bleeding, infection (meningitis) and deterioration of visual acuity and field were detected without statistical difference. New pituitary anterior lobe dysfunction was observed in 30 of 62 patients (48.4%, 8 patients [50.0%] in the 2D-E group and 22 patients [47.8%] in the 3D-E group). A transient deficit of posterior lobe was detected in 22.6% (14/62). No patient died within 30 days of surgery. Although 3D-E may improve surgical dexterity, in this series of lPA and gPA it was not associated with higher resection rates compared to 2D-E. However, 3D-E visualization during resection of large and giant PA is safe and feasible and patient's clinical outcome is not different compared to 2D-E.

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.

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.

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.

Endoscopic Endonasal Skull Base Surgery Complication Avoidance: A Contemporary Review

The endoscopic endonasal approach (EEA) provides a direct trajectory to ventral skull base lesions, avoidance of brain retraction, and clear visualization of cranial nerves as they exit skull base foramina. Despite these benefits, the EEA is not without complications. Here, we review published literature highlighting complications associated with the EEA including cerebrospinal fluid (CSF) leak, cranial nerve (CN) dysfunction, pituitary gland dysfunction, internal carotid artery (ICA) injury, infection, and others; we place special emphasis on discussing the prevention of these complications. As widespread adoption of the EEA continues, it becomes critical to educate surgeons regarding potential complications and their prevention while identifying gaps in the current literature to guide future research and advances in clinical care.

Interpretable Machine Learning-Based Prediction of Intraoperative Cerebrospinal Fluid Leakage in Endoscopic Transsphenoidal Pituitary Surgery: A Pilot Study

Purpose  Transsphenoidal surgery (TSS) for pituitary adenomas can be complicated by the occurrence of intraoperative cerebrospinal fluid (CSF) leakage (IOL). IOL significantly affects the course of surgery predisposing to the development of postoperative CSF leakage, a major source of morbidity and mortality in the postoperative period. The authors trained and internally validated the Random Forest (RF) prediction model to preoperatively identify patients at high risk for IOL. A locally interpretable model-agnostic explanations (LIME) algorithm is employed to elucidate the main drivers behind each machine learning (ML) model prediction. Methods  The data of 210 patients who underwent TSS were collected; first, risk factors for IOL were identified via conventional statistical methods (multivariable logistic regression). Then, the authors trained, optimized, and audited a RF prediction model. Results  IOL reported in 45 patients (21.5%). The recursive feature selection algorithm identified the following variables as the most significant determinants of IOL: Knosp's grade, sellar Hardy's grade, suprasellar Hardy's grade, tumor diameter (on X, Y, and Z axes), intercarotid distance, and secreting status (nonfunctioning and growth hormone [GH] secreting). Leveraging the predictive values of these variables, the RF prediction model achieved an area under the curve (AUC) of 0.83 (95% confidence interval [CI]: 0.78; 0.86), significantly outperforming the multivariable logistic regression model (AUC = 0.63). Conclusion  A RF model that reliably identifies patients at risk for IOL was successfully trained and internally validated. ML-based prediction models can predict events that were previously judged nearly unpredictable; their deployment in clinical practice may result in improved patient care and reduced postoperative morbidity and healthcare costs.

Risk Factors in a Pediatric Population for Postoperative Intracranial Infection Following Endoscopic Endonasal Skull Base Surgery and the Role of Antibiotic Prophylaxis

BACKGROUND

Endoscopic endonasal skull base surgery (EESBS) is performed through a non-sterile corridor. Intracranial infection rates in a pediatric population have not been extensively studied and the exact effect of antibiotic prophylaxis on rates of infection after EESBS in pediatric patients remains unclear.

OBJECTIVE

The purpose of our study is to investigate risk factors for postoperative intracranial infection during EESBS in a pediatric population and help elucidate the role of antibiotic prophylaxis.

METHODS

We conducted a retrospective chart review of 99 consecutive patients under the age of 18 who underwent EESBS at our institution from 2013 to 2021. Centers for Disease Control and Prevention/National Healthcare Safety Network criteria for diagnosis of meningitis were used to identify postoperative intracranial infections.

RESULTS

The average age was 12.3 years (range 1.6-18) with 66 male patients and 33 female patients. 49 patients had an intraoperative cerebrospinal fluid (CSF) leak, of which 4 had a postoperative CSF leak. We identified 3 postoperative intracranial infections (3%), which were all meningitis cases. The infection rate was 6% (3/49) among those with intraoperative CSF leaks. All patients with meningitis had a postoperative CSF leak. All infections were transclival approaches (2 chordoma and 1 neurenteric cyst).

CONCLUSION

This investigation represents one of the largest pediatric endoscopic skull base surgery cohorts. EESBS is safe to perform in pediatric populations, but transclival approaches and postoperative CSF leaks are risk factors for postoperative meningitis.

Endoscopic pituitary surgery: A national database review

BACKGROUND

Pituitary tumors surgery is increasingly performed via endoscopic transsphenoidal approach (TSP). This study describes outcomes of TSP surgery in the United States.

METHODS

A retrospective cross-sectional analysis of adult patients with pituitary adenoma was performed using the Nationwide Readmissions Database, 2010-2015.

RESULTS

A total of 5891 patients were identified. The average age was 51.29 ± 0.29 years. The risk of postoperative epistaxis, diabetes insipidus, cerebrospinal fluid (CSF) leak, and other general postoperative complications was 0.71%, 10.20%, 8.35%, and 2.37%, respectively. Independent risk factors of CSF leak included: age <65-year, male, body mass index ≥25, and multiple comorbidities (p < 0.001 each). The prevalence of CSF leak was not associated with hospital TSP volume and teaching status.

CONCLUSION

This study provides a national epidemiological perspective on TSP in the United States. The risk of postoperative CSF leak appears to be associated with intrinsic patient factors rather than resource and expertise availability.

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.

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.

Transsphenoidal Surgery of Giant Pituitary Adenoma: Results and Experience of 239 Cases in A Single Center

BACKGROUND

Transsphenoidal surgery (TSS) is first-line treatment for giant pituitary adenomas (PAs). Although PA is a benign neuroendocrine tumor that originates from adenohypophysial cells, the surgical outcomes and prognosis of giant PAs differ significantly due to multiple factors such as tumor morphology, invasion site, pathological characteristics and so on. The aim of this study was to evaluate surgical outcomes of giant PAs in a single-center cohort.

METHODS

The clinical features and outcomes of 239 patients with giant PA who underwent sphenoidal surgery at the Second Affiliated Hospital of Zhejiang University School of Medicine from January 2015 to October 2021 were collected from medical records. The basic clinical information (age, gender, function etc.), surgical procedure, imaging features (maximum diameter, invasion characteristics, tumor shape etc.) and histopathological characteristics (pathological results, Ki-67, P53 etc.) were retrospectively reviewed. SPSS 25.0 and Stata 12.0 software were used for statistical analysis.

RESULTS

A total of 239 patients with giant PAs underwent TSS, of which 168 surgeries (70.29%) were endoscopic endonasal transsphenoidal (EETS) and 71 (29.71%) were microscopic transsphenoidal (MTS). The mean preoperative maximum diameter in the cohort was 45.64 mm. Gross-total resection was achieved in 46 patients (19.25%), near-total in 56 (23.43%), subtotal in 68 (28.45%), and partial in 69 (28.87%) patients. The maximum tumor diameter and Knosp grade were the significant factors that limited the extent of the resection of giant PAs. A total of 193 patients (80.75%) experienced surgical complications, and the most common complications were postoperative diabetes insipidus (DI) (91, 38.08%), intracranial infection (36, 15.06%) and cerebrospinal fluid (CSF) leaks (37, 15.48%). In addition, there was a significant difference in the incidence of CSF leaks between the neuroendoscopy group and the microscopic group (P < 0.05).

CONCLUSION

The management of giant PAs remains a therapeutic challenge due to their large size and postoperative complications. The maximum diameter and Knosp grade of giant PAs significantly limited the extent of resection, which warrants a reasonable surgical plan.

Sinonasal Packing is Not a Requisite for Successful Cerebrospinal Fluid Leak Repair

Background Numerous methods have been described to repair nasal cerebrospinal fluid (CSF) leaks. Most studies have focused on optimizing CSF leak repair success, leading to closure rates of 90 to 95%.

Objective This study aimed to determine if excellent reconstruction rates could be achieved without using sinonasal packing.

Methods A prospective case series of 73 consecutive patients with various CSF leak etiologies and skull base defects was conducted to evaluate reconstruction success without sinonasal packing. The primary outcome measure was postoperative CSF leak. Secondary outcome measures were postoperative epistaxis requiring intervention in operating room or emergency department, infectious sinusitis, and 22-item sinonasal outcome test (SNOT-22) changes.

Results Mean age was 54.5 years and 64% were female. Multilayered reconstructions were performed in 55.3% of cases, with collagen or bone epidural inlay grafts, and nasal mucosal grafts or nasoseptal flaps for onlay layers. Onlay-only reconstructions with mucosal grafts or nasoseptal flaps were performed in 44.7% of cases. Tissue sealants were used in all cases, and lumbar drains were used in 40.8% of cases. There were two initial failures (97.4% initial success), but both resolved with lumbar drains alone (no revision surgeries). There were no instances of postoperative epistaxis requiring intervention in the operating room or emergency department. Infectious sinusitis occurred in 2.7% of patients in the first 3 months postoperatively. SNOT-22 did not change significantly from preoperatively to first postoperative visits, then improved over time.

Conclusion Nasal CSF leaks from various etiologies and defect sites were successfully repaired without using sinonasal packing, and patients experienced minimal sinonasal morbidity.

Risk factors impacting intra- and postoperative cerebrospinal fluid rhinorrhea on the endoscopic treatment of pituitary adenomas: A retrospective study of 250 patients

We aimed to identify the risk factors associated with intra- and postoperative cerebrospinal fluid (CSF) leakage in pituitary adenomas treated with endoscopic transsphenoidal surgery.This study is a retrospective analysis of 250 pituitary adenoma cases from January 2017 to December 2019 at our hospital. All patients underwent endoscopic endonasal transsphenoidal surgeries. Univariate and multivariate analyses were performed to investigate the risk factors associated with intra- and postoperative CSF rhinorrhea.Eighty (32.0%) and nine (3.6%) patients had intra- and postoperative CSF leakage, respectively. Tumor size was an independent risk factor for intraoperative CSF leakage (odds ratio [OR], 1.229; 95% confidence interval [CI], 1.133-1.334; P < .001); intraoperative CSF leakage was an independent risk factor for postoperative CSF leakage (OR, 7.707; 95% CI, 1.336-44.455; P = .022). Chronic respiratory disease (OR, 57.500; 95% CI, 8.031-411.682; P < .001) was also an independent risk factor for postoperative CSF leakage. Vascularized septal mucosal flap was a protective factor (OR, 0.107; 95% CI, 0.013-0.894; P = .039).Intraoperative CSF leakage is more likely to occur in large pituitary adenomas. In the presence of intraoperative CSF leakage, postoperative CSF rhinorrhea is very likely to occur. Patients with chronic respiratory disease are also more likely to develop postoperative CSF leakage. The sellar base reconstructed using vascularized nasal septal flaps can significantly decrease the risk. The Knosp grade, degree of tumor resection, and postoperative use of a lumbar subarachnoid drain did not have any effects on postoperative CSF rhinorrhea.

Development and Validation of Nomogram to Preoperatively Predict Intraoperative Cerebrospinal Fluid Leakage in Endoscopic Pituitary Surgery: A Retrospective Cohort Study

Background

Pituitary adenomas (PAs) are the most common tumor of the sellar region. PA resection is the preferred treatment for patients with clear indications for surgery. Intraoperative cerebrospinal fluid (iCSF) leakage is a major complication of PA resection surgery. Risk factors for iCSF leakage have been studied previously, but a predictive nomogram has not yet been developed. We constructed a nomogram for preoperative prediction of iCSF leakage in endoscopic pituitary surgery.

Methods

A total of 232 patients who underwent endoscopic PA resection at the Department of Neurosurgery in Jinling Hospital between January of 2018 and October of 2020 were enrolled in this retrospective study. Patients treated by a board-certified neurosurgeon were randomly classified into a training cohort or a validation cohort 1. Patients treated by other qualified neurosurgeons were included in validation cohort 2. A range of demographic, clinical, radiological, and laboratory data were acquired from the medical records. The Least Absolute Shrinkage and Selection Operator (LASSO) algorithm and uni- and multivariate logistic regression were utilized to analyze these features and develop a nomogram model. We used a receiver operating characteristic (ROC) curve and calibration curve to evaluate the predictive performance of the nomogram model.

Results

Variables were comparable between the training cohort and validation cohort 1. Tumor height and albumin were included in the final prediction model. The area under the curve (AUC) of the nomogram model was 0.733, 0.643, and 0.644 in training, validation 1, and validation 2 cohorts, respectively. The calibration curve showed satisfactory homogeneity between the predicted probability and actual observations. Nomogram performance was stable in the subgroup analysis.

Conclusions

Tumor height and albumin were the independent risk factors for iCSF leakage. The prediction model developed in this study is the first nomogram developed as a practical and effective tool to facilitate the preoperative prediction of iCSF leakage in endoscopic pituitary surgery, thus optimizing treatment decisions.

Heterogeneity in Outcome Reporting in Endoscopic Endonasal Skull Base Reconstruction: A Systematic Review

Objective  Presently, there are no standards for reporting outcomes of endoscopic endonasal skull base reconstruction (ESBR). This is problematic as a lack of consistent reporting makes synthesizing findings in systematic reviews and meta-analysis challenging. Thus, the aim of this study was to systematically review and describe the patterns of reporting outcomes in ESBR as a foundation for developing reporting guidelines. Study Design  Present study is a systematic review. Methods  Embase, PubMed, CINAHL, Cochrane Library, and Web of Science were searched for all publications with ≥25 patients and a focus on ESBR. The reporting patterns of each study's variables and outcomes were assessed. Results  A total of 112 studies were included in the review. The most commonly reported demographic variables were the number of included patients ( n  = 112, 100%) and types of pathologies treated ( n  = 104, 92.9%). Meanwhile, the most routinely described preoperative variable was history of prior treatment ( n  = 48, 42.9%). Type of reconstruction was a commonly reported intraoperative variable ( n  = 110, 98.2%), though the rate of intraoperative cerebrospinal fluid (CSF) leak was noted in only 76 studies (67.9%). With regard to postoperative outcomes, postoperative CSF leak rate was routinely provided ( n  = 101, 90.2%), but reporting of other surgical complications was more inconsistent. Ultimately, of the 43 variables and outcomes reviewed, a median of 12 (range: 4-22) was reported in each study. Conclusion  There is significant heterogeneity in the outcomes reported in studies relating to ESBR. This highlights the need for the development of standard reporting guidelines to minimize bias and improve interstudy comparability.

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.

Analysis of modifiable and nonmodifiable risk factors in patients undergoing pituitary surgery

OBJECTIVE

Pituitary adenomas (PAs) are among the most common intracranial tumors. Understanding the clinical effects of various modifiable risk factors (MRFs) and nonmodifiable risk factors (NMRFs) is important in guiding proper treatment, yet there is limited evidence outlining the influence of MRFs and NMRFs on outcomes of PA resection. The aim of this study was to analyze MRFs and NMRFs in patients undergoing resection for PAs.

METHODS

Using the 2016 and 2017 National Readmission Database, the authors identified a cohort of 9472 patients undergoing microscopic or endoscopic resection of a PA. Patients with nonoverlapping MRFs and NMRFs were analyzed for length of stay (LOS), hospital cost, readmission rates, and postoperative complications. From the original cohort, a subset of 373 frail patients (as defined by the Johns Hopkins Frailty Index) were identified and propensity matched to nonfrail patients. Statistical analysis included 1-way ANOVA, Tukey multiple comparisons of means, odds ratios, Wald testing, and unpaired Welch 2-sample t-tests to compare complications, outcomes, and costs between each cohort. Perioperative outcomes and hospital readmission rates were tracked, and predictive algorithms were developed to establish precise relationships between relevant risk factors and neurosurgical outcomes.

RESULTS

Malnourished patients had significantly longer LOSs when compared to nonmalnourished patients (p < 0.001). There was a significant positive correlation between the number of MRFs and readmission at 90 days (p = 0.012) and 180 days (p = 0.020). Obese patients had higher rates of postoperative neurological injury at the 30-day follow-up (p = 0.048) compared to patients with normal BMI. Within this NMRF cohort, frail patients were found to have significantly increased hospital LOS (p < 0.001) and total inpatient costs compared to nonfrail patients (p < 0.001). Predictive analytics showed that frail patients had significantly higher readmission rates at both 90-day (p < 0.001) and 180-day follow-ups (p < 0.001). Lastly, rates of acute postsurgical infection were higher in frail patients compared to nonfrail patients (p < 0.001).

CONCLUSIONS

These findings suggest that both MRFs and NMRFs negatively affect the perioperative outcomes following PA resection. Notable risk factors including malnutrition, obesity, elevated lipid panels, and frailty make patients more prone to prolonged LOS, higher inpatient costs, and readmission. Further prospective research with longitudinal data is required to precisely pinpoint the effects of various risk factors on the outcomes of pituitary surgery.

The effect of prior radiation on the success of ventral skull base reconstruction: A systematic review and meta-analysis

The incidence of cerebrospinal fluid leak after ventral skull base reconstruction is a primary outcome of interest to skull base surgeons. Exposure to pre-operative radiation may put patients at an increased risk of skull base reconstructive failure. A systematic search identified studies which included patients receiving ventral skull base reconstruction in the setting of pre-operative radiation. A meta-analysis using a random effects model was conducted to estimate an odds ratio of cerebrospinal fluid (CSF) leak in patients exposed to pre-operative radiation. A meta-analysis of 13 studies demonstrated that the odds ratio of CSF leak was 1.73 (95% CI 0.98-3.05). The majority of studies (77%) used vascularized tissue grafts for reconstruction. We identified an increased incidence of CSF leak among patients undergoing ventral skull base reconstruction after prior radiation therapy, although not of statistical significance. Skull base surgeons should exercise caution when planning reconstruction in this population.

Characteristics and overall survival in pediatric versus adult craniopharyngioma: a population-based study

PURPOSE

This study uses a large-population national database to describe the presenting clinical, sociodemographic, treatment, and clinical outcome differences between pediatric and adult craniopharyngiomas.

METHODS

This study utilized the 2004-2015 National Cancer Database and was queried for all cases of craniopharyngioma. Multivariate Cox proportional-hazards analysis was used to determine clinical and sociodemographic factors associated with mortality. Kaplan-Meier log-rank test determined differences in overall survival (OS) time.

RESULTS

The cohort consisted of 3638 patients, with 816 (22.4%) pediatric (≤ 18 years) patients. Pediatric patients presented with significantly higher frequency of large tumors (> 3 cm, 54.1 vs. 31.8%, p < 0.001), lower frequency of papillary subtype (0.9 vs. 11.5%, p < 0.001), and were exclusively treated at academic centers (100 vs. 73.4%, p < 0.001). Pediatric patients had significantly higher rates of adjuvant radiation (34.3 vs. 22.3%; p < 0.001), and had significantly lower 90-day mortality (1.6 vs. 4.9%; p < 0.001); however, no significant differences in extent of resection (p = 0.93), length of hospital stay (p = 0.53), and 30-day readmissions (p = 0.06) were observed between pediatric and adult patients. On Kaplan-Meier log-rank test, there were no significant differences in OS in pediatric patients receiving gross total resection (GTR), subtotal resection (STR), or STR + adjuvant radiation (p = 0.68). Lastly, when comparing endoscopic and open surgical approaches in pediatric patients, there were no significant differences in extent of surgical resection (p = 0.81), length of hospital stay (p = 0.54), 30-day readmissions (p = 0.22), and 90-day mortality (p = 0.80).

CONCLUSION

Craniopharyngioma has improved OS in pediatric compared to adult patients. Pediatric craniopharyngioma patients are best managed within multidisciplinary teams at academic centers with an individualized approach.

Reconstruction after extended endonasal approaches to the anterior cranial base: surgical techniques and current results

The development of extended endoscopic endonasal approaches (EEA) to the anterior skull base has allowed successful resection of selected extradural and intradural skull base tumors through an endonasal corridor, minimizing brain and cranial nerve manipulation. However, as the complexity of the approaches has increased, so has the need for more robust and reliable reconstructive options to minimize morbidity. Reconstructive decision-making after extended EEA for anterior skull base tumors must take into consideration multiple factors including patient characteristics (Body Mass Index, previous surgeries, and radiation), location and the size of the skull base defect. A multilayered reconstruction which includes a combination of free grafts and a vascularized flap is the standard approach to anterior skull base defects after EEA and should be applied in a stepwise manner tailored to each patient. The techniques and materials used to accomplish skull base repair are discussed, the outcomes in the literature are reviewed, and our reconstructive paradigm presented.

Endoscopic Reconstruction of Skull Base Defects Using Tutoplast

BACKGROUND

Various graft materials that are classified as autografts, xenografts, and allografts based on their origin have been used to endoscopically repair skull base defects. Tutoplast® (Tutogen Medical GmbH), an allogeneic natural collagen matrix, is processed through chemical sterilization that preserves tissue biocompatibility and structural integrity.

OBJECTIVE

To study the safety and efficacy of Tutoplast Fascia Lata and Tutoplast Temporalis Fascia® as primary graft materials in the endoscopic reconstruction of skull base defects of different sizes and etiologies and to compare the outcomes with those of other traditional graft materials based on our experience.

METHODS

This is a multi-center retrospective chart review of patients who underwent cerebrospinal fluid leak (CSF) endoscopic reconstruction with Tutoplast Fascia Lata or Tutoplast Temporalis Fascia as either a stand-alone reconstruction material or a part of a multilayer reconstruction depending on the defect at Prince Sultan Military Medical City and King Faisal Specialist Hospital and Research Center in Riyadh, Saudi Arabia, between 2017 and 2020. Our inclusion criteria were CSF leak repair with Tutoplast and a transnasal endoscopic approach. We reviewed demographic data, intraoperative and postoperative complications, repair materials, repair failure, defect size and location.

RESULTS

Tutoplast® was used as the primary graft material in 33 cases. Our main outcome was repair success with lack of post operative CSF leak, observed in 30 cases (90.9%). There was no significant association between postoperative CSF leaks and factors including different defect sizes, defect sites, demographic data, hospitalization duration, or postoperative radiation in oncological cases.

CONCLUSION

Tutoplast alone or in combination with other materials can be used safely and effectively for skull base defects repair.

Vascular pedicled flaps for skull base defect reconstruction

OBJECTIVE

Techniques for reconstruction of skull base defects have advanced greatly since the introduction of the vascular pedicled nasoseptal flap in 2006. The objective of this review is to assess the current state of the field by examining both intranasal and extranasal techniques of vascular pedicled skull base defect repair, their indications and success rates, and novel techniques that are currently under investigation.

METHODS

A review of the literature describing the use of vascular pedicled flaps in skull base defect reconstruction was conducted using PubMed and Google Scholar.

RESULTS

The nasoseptal flap remains the most widely used vascular pedicled flap for endoscopic repair of skull base defects. Its ease of harvest, wide arch of rotation, and high success rates make it a popular choice among surgeons. Several variations including a "rescue" nasopseptal flap have been developed. Other less commonly used pedicled intranasal flaps include the middle turbinate flap and the posterior pedicled inferior turbinate flap. Additionally, several novel vascular pedicled flaps have been developed and tested in small cohorts of patients. Extranasal flaps such as the pericranial flap and the temporoparietal fascia flap are used less frequently than intranasal flaps. However, they remain valuable options for reconstruction in certain situations.

CONCLUSION

Advancements continue to be made in the field of skull base defect reconstruction using vascular pedicled flaps. Though the nasoseptal flap remains the most widely utilized option, additional intranasal techniques continue to be developed and tested to optimize surgical outcomes and patient care.

LEVEL OF EVIDENCE

NA.

Neural network-based identification of patients at high risk for intraoperative cerebrospinal fluid leaks in endoscopic pituitary surgery

OBJECTIVE

Although rates of postoperative morbidity and mortality have become relatively low in patients undergoing transnasal transsphenoidal surgery (TSS) for pituitary adenoma, cerebrospinal fluid (CSF) fistulas remain a major driver of postoperative morbidity. Persistent CSF fistulas harbor the potential for headache and meningitis. The aim of this study was to investigate whether neural network-based models can reliably identify patients at high risk for intraoperative CSF leakage.

METHODS

From a prospective registry, patients who underwent endoscopic TSS for pituitary adenoma were identified. Risk factors for intraoperative CSF leaks were identified using conventional statistical methods. Subsequently, the authors built a prediction model for intraoperative CSF leaks based on deep learning.

RESULTS

Intraoperative CSF leaks occurred in 45 (29%) of 154 patients. No risk factors for CSF leaks were identified using conventional statistical methods. The deep neural network-based prediction model classified 88% of patients in the test set correctly, with an area under the curve of 0.84. Sensitivity (83%) and specificity (89%) were high. The positive predictive value was 71%, negative predictive value was 94%, and F1 score was 0.77. High suprasellar Hardy grade, prior surgery, and older age contributed most to the predictions.

CONCLUSIONS

The authors trained and internally validated a robust deep neural network-based prediction model that identifies patients at high risk for intraoperative CSF. Machine learning algorithms may predict outcomes and adverse events that were previously nearly unpredictable, thus enabling safer and improved patient care and better patient counseling.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Preoperative radiographic and clinical factors associated with the visualization of intraoperative cerebrospinal fluid during endoscopic transsphenoidal resection of pituitary adenomas

Background:

Intraoperative visualization of cerebrospinal fluid (CSF) during endoscopic endonasal resection of skull base tumors is the most common factor contributing to the development of postoperative CSF leaks. No previous studies have solely evaluated preoperative factors contributing to intraoperative CSF visualization. The purpose of this study was to identify preoperative factors predictive of intraoperative CSF visualization.

Methods:

Retrospective review of patients who underwent transsphenoidal resection of pituitary adenomas was conducted. Clinical and radiographic variables were compared for those who had CSF visualized to those who did not. Nominal logistic regression models were built to determine predictive variables.

Results:

Two hundred and sixty patients were included in the study. All significant demographic and radiographic variables on univariate analysis were included in multivariate analysis. Two multivariate models were built, as tumor height and supraclinoid extension were collinear. The first model, which considered tumor height, found that extension into the third ventricle carried a 4.60-fold greater risk of CSF visualization (P = 0.005). Increasing tumor height showed a stepwise, linear increase in risk; tumors >3 cm carried a 19.02-fold greater risk of CSF visualization (P = 0.003). The second model, which considered supraclinoid tumor extension, demonstrated that extension into the third ventricle carried a 4.38-fold increase in risk for CSF visualization (P = 0.010). Supraclinoid extension showed a stepwise, linear increase in intraoperative CSF risk; tumors with >2 cm of extension carried a 9.26-fold increase in risk (P = 0.017).

Conclusion:

Our findings demonstrate that tumor height, extension into the third ventricle, and extension above the clinoids are predictive of intraoperative CSF visualization.

Endonasal endoscopic surgery for pediatric anterior cranial fossa encephaloceles: A systematic review

BACKGROUND

Endoscopic endonasal skull base surgery (ESBS) is a well-established management strategy for anterior cranial fossa (ACF) encephaloceles in adults. However, its application to the pediatric population has not been evaluated in large-scale studies. This study systematically reviews the safety of ESBS for pediatric ACF encephaloceles.

METHODS

Articles reporting on pediatric patients undergoing purely ESBS for encephaloceles were reviewed from three databases (PubMed, Scopus, and Cochrane Library). Main outcomes were post-operative cerebrospinal fluid (CSF) leak and other surgical complications.

RESULTS

Twenty-three articles provided data on 110 eligible patients with a mean age of 4.3 years (range birth - 18 years). Intraoperative CSF leaks occurred in 18.5% of children while post-operative CSF leaks developed in 6.0% of cases. Rates of meningitis and hydrocephalus were each 3.7%. Other complications included alar collapse, nasal stenosis, transient diabetes insipidus, pneumonia, and neurologic injury, collectively occurring in 7.0% of cases. The rate of death was 4.8%. The average duration of follow-up was 25.3 months. Encephaloceles recurred in 5.2% of patients.

CONCLUSIONS

ESBS for pediatric ACF encephaloceles provides a relatively favorable risk-benefit profile, with a low rate of post-operative CSF leak, other surgical complications, and disease recurrence.

Endonasal Endoscopic Surgery for Pediatric Sellar and Suprasellar Lesions: A Systematic Review and Meta-analysis

OBJECTIVES

The advent of endonasal endoscopic skull base surgery (ESBS) has redefined the management of pediatric sellar and suprasellar lesions. To date, the outcomes of these procedures have not been systematically reviewed. This study performed a systematic review with meta-analysis of surgical outcomes for pediatric patients undergoing ESBS for sellar and suprasellar lesions.

DATA SOURCES

PubMed (National Library of Medicine, National Institutes of Health), Scopus (Elsevier), and Cochrane Library (Wiley).

REVIEW METHODS

Articles reporting on pediatric patients undergoing ESBS for craniopharyngiomas, pituitary adenomas, and Rathke's cleft cysts were reviewed. The primary outcome was postoperative cerebrospinal fluid (CSF) leak. Secondary outcomes included endocrine, visual, and other complications.

RESULTS

Twenty-five articles reporting on 554 patients were included. Overall postoperative CSF leak rate was 8.6%, with tumor-specific rates of 10.6% in craniopharyngiomas, 6.5% in pituitary adenomas, and 7.2% in Rathke's cleft cysts (P > .05). Older studies demonstrate higher postoperative CSF leak rates as compared with more recent studies (12.5% vs 6.1%, P = .0082). Younger children (8.9-12.6 years old) experienced a higher rate of postoperative CSF leaks as compared with older children (13.0-16.6 years old; 12.9% vs 4.9%, P = .0016). Additional postoperative complications included diabetes insipidus (26.7%), hypopituitarism (46.6%), visual deficits (2.6%), meningitis (3.4%), and weight gain (3.4%).

CONCLUSION

ESBS for pediatric sellar and suprasellar lesions is overall an effective management approach with an increasingly favorable risk-benefit profile. Younger children may be more susceptible to postoperative CSF leak as compared with older pediatric patients. Tumor type does not appear to be an independent risk factor for postoperative CSF leak in this population.

Quality of life and emotional burden after transnasal and transcranial anterior skull base surgery

OBJECTIVE

To analyze psychopathological outcome and health-related quality of life (QOL) for cohorts of patients undergoing transcranial or transnasal anterior skull base surgery.

METHODS

A prospective study of patients undergoing elective surgery for various entities of the anterior skull base was performed. Evaluation for depression (ADS-K score) and anxiety (PTSS, STAI-S, STAI-T, and ASI-3 scores) was done before surgery, at 3 and 12 months after surgery. The correlation between preoperative psychological burden and postoperative quality of life as measured by the SF-36 and EuroQol questionnaires was analyzed. Incidence and influence of these psychiatric comorbidities on clinical outcome were examined and compared between transnasal and transcranial subgroups.

RESULTS

We included 54 patients scheduled for surgery of a pituitary adenoma or meningioma of the anterior skull base between January 2013 and July 2017. Of these, a cohort of 40 (74.1%) completed follow-up interviews after 3 and 12 months. There were 60.0% female patients, median age was 57 years. 57.5% of patients had a meningioma and were operated transcranially, while 42.5% of patients received transnasal surgery for pituitary adenoma. The proportion of pathological anxiety scores significantly decreased from 75.0 to 45.0% (p = 0.002), without difference between transnasal and transcranial subgroups. After 3 months, mean EuroQol VAS score non-significantly increased by 0.07 (p = 0.236) across the entire cohort without significant difference between transcranial and transnasal subgroups (p = 0.478). The transnasal cohort tended to score higher in anxiety scores, whereas the transcranial cohort demonstrated higher depression scores without significant difference, respectively. The individually declared emotional burden significantly decreased from 6.7 to 4.0 on the ten-point Likert scale (p < 0.001) equally for both subgroups (transnasal, - 2.3; transcranial, - 3.0; p = 0.174). On last examination, about half of the patients in each subgroup (41.2% vs. 52.2%; p = 0.491) expressed a considerable recovery of preoperative bodily complaints such as headaches, dizziness, and unrest defined as a score of at least 8 on the Likert scaled item.

CONCLUSION

Both transnasal and transcranial approaches yield favorable postoperative QOL and psychopathological outcomes. The postoperative increase in QOL is partly influenced by preoperative expression of mental distress, which tends to resolve postoperatively.

Readmissions after endoscopic skull base surgery: associated risk factors and prevention

BACKGROUND

Unplanned readmissions within 30 days of discharge is a quality measure introduced by the Centers for Medicare Services. This measure has been used to rate hospital quality and also to penalize hospitals for excess readmissions. It has been hypothesized that shorter hospital stays and fewer readmissions are associated with endoscopic skull base procedures. In this study we analyze endoscopic skull base procedures performed at our institution over a 10-year period to identify rates and factors associated with readmissions after endoscopic skull base surgery.

METHODS

A retrospective chart review was performed at a tertiary care academic medical center identifying patients who underwent endoscopic skull base surgery over the past 10 years. Data on patient demographics and tumor variables, as well as patient variables such as body mass index (BMI), revision surgery, history of skull base radiation, medical comorbidities, intraoperative cerebrospinal fluid (CSF) leaks, and postoperative CSF leaks, were recorded.

RESULTS

Eight hundred thirty-three patients were included in our study. Sixty-one patients (7.3%) were readmitted a total of 66 times within 30 days. The most common reasons were as follows: hyponatremia (n = 18); CSF leak (n = 17); epistaxis (n = 3); diabetes insipidus (n = 3); rhinorrhea (n = 3); as well as other reasons. Statistical analysis revealed that the presence of intraoperative CSF leak was the only statistically significant variable associated with increased rate of readmissions within 30 days of discharge (p < 0.001).

CONCLUSION

Presence of intraoperative CSF leak was the only statistically significant variable associated with an increased risk for readmission after surgery. Other tumor and patient variables were not associated with an increased risk of readmission within 30 days.

Infectious Complications of Expanded Endoscopic Transsphenoidal Surgery: A Retrospective Cohort Analysis of 100 Cases

Objective  To identify perioperative factors that may predict postoperative cerebrospinal fluid (CSF) leak and meningitis following expanded endoscopic transsphenoidal surgery (EETS). Study Design  This is a retrospective study. This study was set at the Cedars-Sinai Medical Center, Los Angeles. A total of 78 patients who underwent EETS between January 2007 and November 2018 were participated. The main outcome measures were CSF leak and meningitis. Results  A total of 78 patients underwent a total of 100 EETS procedures; 17.9 and 10.3% of patients developed postoperative CSF leaks and meningitis, respectively. Out of eight, three patients with meningitis did not develop an observable CSF leak. The risk of developing meningitis in patients with a CSF leak was significantly higher than those without a leak, with an odds ratio (OR) of 11.48 (95% confidence interval, 2.33-56.47; p  = 0.004). Pituicytomas were significantly associated with meningitis compared with other pathologies. No other patient-specific factors were identified as risks for leak or meningitis, including method of skull base repair, sex, tumor volume, or body mass index, although there was a strong trend toward reduced CSF leak rates in patient with nasoseptal flaps used for skull base repair, compared with those without (9.5 vs. 25%). CSF protein was consistently elevated on the first CSF values obtained when meningitis was suspected. Conclusion  CSF leak and meningitis are common complications of expanded endonasal surgery No statistically significant risk factors for developing a postoperative leak other than the pathology of pituicytoma were identified, including method of skull base repair, although the use of a vascularized nasoseptal flap did trend toward a reduced CSF leak rate. CSF protein is the most sensitive marker for the presumptive diagnosis and timely treatment of meningitis.

Proposal of Standardization of Closure Techniques After Endoscopic Pituitary and Skull Base Surgery Based on Postoperative Cerebrospinal Fluid Leak Risk Classification

Postoperative cerebrospinal fluid (CSF) leak still represents the main limitation of endonasal endoscopic surgery. The aim of the study is to classify the risk of postoperative leak and to propose a decision-making protocol to be applied in the preoperative phase based on radiological data and on intraoperative findings to obtain the best closure.One hundred fifty-two patients were treated in our institution; these patients were divided into 2 groups because from January 2013 the closure technique was standardized adopting a preoperative decision-making protocol. The Postoperative CSF leak Risk Classification (PCRC) was estimated taking into account the size of the lesion, the extent of the osteodural defect, and the presence of intraoperative CSF leak (iCSF-L). The closure techniques were classified into 3 types according to PCRC estimation (A, B, and C).The incidence of the use of a nasoseptal flap is significantly increased in the second group 80.3% versus 19.8% of the first group and the difference was statistically significant P < 0.0001. The incidence of postoperative CSF leak (pCSF-L) in the first group was 9.3%. The incidence of postoperative pCSF-L in the second group was 1.5%. An analysis of the pCSF-L rate in the 2 groups showed a statistically significant difference P = 0.04.The type of closure programmed was effective in almost all patients, allowing to avoid the possibility of a CSF leak. Our protocol showed a significant total reduction in the incidence of CSF leak, but especially in that subgroup of patients where a leak is usually unexpected.

Predictors of Nasoseptal Flap Use After Endoscopic Transsphenoidal Pituitary Mass Resection

OBJECTIVE

The pedicled nasoseptal flap (NSF) is the widely accepted reconstructive technique of choice for repair of larger skull base defects after endoscopic endonasal approaches. There is a dearth of literature examining the decision-making process regarding flap harvest. The objective of this study is to evaluate preoperative characteristics that predict the use of NSF reconstruction after endoscopic transsphenoidal resection of pituitary tumors.

METHODS

In this retrospective case control study, demographic, clinical, imaging, and procedural details were gathered on all patients undergoing endoscopic transsphenoidal pituitary adenoma resection at a single academic center since January 2009. Characteristics were compared for patients receiving an NSF and those not undergoing NSF repair. A multivariate model that best predicted the use of an NSF was built and a risk score was developed.

RESULTS

Two hundred thirty-eight patients were included, and 39 underwent NSF placement. Tumor size and anatomic characteristics were the predominant factors that significantly differed between cases and controls. Patients with transsellar tumor extension had 6.3 higher odds of requiring NSF, each millimeter increase in tumor height on coronal T1 magnetic resonance imaging increased the odds of NSF use by 1.2. The flap risk score (FRS) is calculated by adding tumor height (mm) to 6 if there is transsellar extension. At an FRS of >35, the FRS is 87% specific and 85% sensitive for flap placement.

CONCLUSIONS

Preoperative imaging characteristics can predict NSF use. The FRS can be applied by surgical teams and referring physicians to determine which patients are more likely to undergo NSF repair.