Learning curve for the transsphenoidal endoscopic endonasal approach to pituitary tumors

Single Center Neurosurgical Outcomes and Trends in Endoscopic Endonasal Resection of 297 Sellar/Suprasellar Tumors Stratified by Duration of Neurosurgical Career

BACKGROUND/OBJECTIVE

Endoscopic endonasal transsphenoidal surgery (EETS) is a common treatment for sellar and suprasellar tumors. While endoscopic training has improved over the years and formal fellowship training is now broadly available, the operative nuances of EETS conjectures the existence a learning curve as a neurosurgeon matures with experience. We aim to evaluate operative outcomes of 3 different experience levels of neurosurgeons over time at a single institution.

METHODS

We reviewed all adult patients who underwent EETS at Loyola University Medical Center by 3 early career, 1 midcareer, and 2 late career neurosurgeons from 2007 to 2023. A comparative assessment of patient demographics, tumor features, and surgical outcomes was done using metrics such as length of surgery, rates of gross total resection (GTR) and symptomatic improvement, new postoperative steroid dependence, and development of diabetes insipidus (DI). T-tests and χ2 were used to statistically evaluate the study cohorts.

RESULTS

A total of 297 patients underwent EETS. One hundred three (35%) were operated on by an early career, 122 (41%) by a mid-career, and 72 (24%) by a late career neurosurgeon. Late-career surgeons had shorter operation times (144 vs. 180 minutes with early and mid-career, P = 0.029) and increased GTR rates (P = 0.008). There were no significant differences between the symptomatic improvement rates amongst various surgeon experience levels. Although not statistically significant, early-career neurosurgeons had lower rates of new postoperative steroid dependence. Patients of early career surgeons experienced significantly less DI (15% vs. 40%, P = 0.004).

CONCLUSIONS

Late-career neurosurgeons had shorter operation lengths, achieved higher rates of GTR, and their patients experienced significantly higher rates of DI. Overall outcomes remained stable throughout the course of 16 years between different surgeon experience levels.

Collaborative Human-Computer Vision Operative Video Analysis Algorithm for Analyzing Surgical Fluency and Surgical Interruptions in Endonasal Endoscopic Pituitary Surgery: Cohort Study

BACKGROUND

The endonasal endoscopic approach (EEA) is effective for pituitary adenoma resection. However, manual review of operative videos is time-consuming. The application of a computer vision (CV) algorithm could potentially reduce the time required for operative video review and facilitate the training of surgeons to overcome the learning curve of EEA.

OBJECTIVE

This study aimed to evaluate the performance of a CV-based video analysis system, based on OpenCV algorithm, to detect surgical interruptions and analyze surgical fluency in EEA. The accuracy of the CV-based video analysis was investigated, and the time required for operative video review using CV-based analysis was compared to that of manual review.

METHODS

The dominant color of each frame in the EEA video was determined using OpenCV. We developed an algorithm to identify events of surgical interruption if the alterations in the dominant color pixels reached certain thresholds. The thresholds were determined by training the current algorithm using EEA videos. The accuracy of the CV analysis was determined by manual review, and the time spent was reported.

RESULTS

A total of 46 EEA operative videos were analyzed, with 93.6%, 95.1%, and 93.3% accuracies in the training, test 1, and test 2 data sets, respectively. Compared with manual review, CV-based analysis reduced the time required for operative video review by 86% (manual review: 166.8 and CV analysis: 22.6 minutes; P<.001). The application of a human-computer collaborative strategy increased the overall accuracy to 98.5%, with a 74% reduction in the review time (manual review: 166.8 and human-CV collaboration: 43.4 minutes; P<.001). Analysis of the different surgical phases showed that the sellar phase had the lowest frequency (nasal phase: 14.9, sphenoidal phase: 15.9, and sellar phase: 4.9 interruptions/10 minutes; P<.001) and duration (nasal phase: 67.4, sphenoidal phase: 77.9, and sellar phase: 31.1 seconds/10 minutes; P<.001) of surgical interruptions. A comparison of the early and late EEA videos showed that increased surgical experience was associated with a decreased number (early: 4.9 and late: 2.9 interruptions/10 minutes; P=.03) and duration (early: 41.1 and late: 19.8 seconds/10 minutes; P=.02) of surgical interruptions during the sellar phase.

CONCLUSIONS

CV-based analysis had a 93% to 98% accuracy in detecting the number, frequency, and duration of surgical interruptions occurring during EEA. Moreover, CV-based analysis reduced the time required to analyze the surgical fluency in EEA videos compared to manual review. The application of CV can facilitate the training of surgeons to overcome the learning curve of endoscopic skull base surgery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06156020; https://clinicaltrials.gov/study/NCT06156020.

The learning curve in endoscopic transsphenoidal skull-base surgery: a systematic review

BACKGROUND

The endoscopic endonasal transsphenoidal approach (EETA) has revolutionized skull-base surgery; however, it is associated with a steep learning curve (LC), necessitating additional attention from surgeons to ensure patient safety and surgical efficacy. The current literature is constrained by the small sample sizes of studies and their observational nature. This systematic review aims to evaluate the literature and identify strengths and weaknesses related to the assessment of EETA-LC.

METHODS

A systematic review was conducted following the PRISMA guidelines. PubMed and Google Scholar were searched for clinical studies on EETA-LC using detailed search strategies, including pertinent keywords and Medical Subject Headings. The selection criteria included studies comparing the outcomes of skull-base surgeries involving pure EETA in the early and late stages of surgeons' experience, studies that assessed the learning curve of at least one surgical parameter, and articles published in English.

RESULTS

The systematic review identified 34 studies encompassing 5,648 patients published between 2002 and 2022, focusing on the EETA learning curve. Most studies were retrospective cohort designs (88%). Various patient assortment methods were noted, including group-based and case-based analyses. Statistical analyses included descriptive and comparative methods, along with regression analyses and curve modeling techniques. Pituitary adenoma (PA) being the most studied pathology (82%). Among the evaluated variables, improvements in outcomes across variables like EC, OT, postoperative CSF leak, and GTR. Overcoming the initial EETA learning curve was associated with sustained outcome improvements, with a median estimated case requirement of 32, ranging from 9 to 120 cases. These findings underscore the complexity of EETA-LC assessment and the importance of sustained outcome improvement as a marker of proficiency.

CONCLUSIONS

The review highlights the complexity of assessing the learning curve in EETA and underscores the need for standardized reporting and prospective studies to enhance the reliability of findings and guide clinical practice effectively.

The Learning Curve for Endoscopic Endonasal Transsphenoidal Pituitary Surgery: Evaluating Endocrine Outcomes

OBJECTIVE

In South Australia endoscopic endonasal approach (EEA) pituitary surgery has been practiced since 2006, largely by two neurosurgeons with a small fellowship-trained otolaryngology team. The aim of this cohort study was to determine if a "learning curve" can be established over this time period, as represented by structural and endocrine patient outcomes.

METHOD

Retrospective cohort study of patients undergoing EEA surgery between 2006 and 2021 in Adelaide, South Australia at three tertiary teaching hospitals.. Cases were divided by each surgeon and split into groups of sequential 40 cases. Endocrine assessment pre- and post-operatively involved static pituitary and end-organ hormones, with dynamic tests as required, assessed by an pituitary endocrinologist. Each hormonal axis (gonadal, cortisol, thyroid, prolactin and growth hormone) was documented preoperatively and at an early and long term follow up at 1-2 and 12 months, respectively.

RESULTS

The study included a cohort of 443 pituitary adenomas managed with endoscopic endonasal transsphenoidal surgery in a consecutive fashion between two neurosurgeons over 16-years. Gross tumour resection but not visual visual outcomes improved with surgical experience but this outcome may be neurosurgeon dependent. Endocrine outcomes were not consistently improved with experience, but lower rates of hypopituitarism were seen with experience with one neurosurgeon. Average follow up was approximately 5 years, and a minimum follow up of 12 months for all patients.

CONCLUSIONS

We present long term endocrine follow up for patients with functional and non-functional adenomas. Improved rates of gross tumour resection were evident with with surgical experience. However, there was no apparent change in post-operative endocrine outcomes.

Exposure of the Cavernous Sinus via the Endoscopic Transorbital and Endoscopic Endonasal Approaches: A Comparative Study

OBJECTIVE

To compare the endoscopic transorbital approach (ETOA) and endoscopic endonasal approach (EEA) in terms of cavernous sinus (CS) exposure.

METHODS

Four cadaveric heads (8 sides) were dissected. The CS was accessed using the EEA and ETOA. Stereotactic measurements of the length of the main structures exposed, angles of attack, depths of surgical corridor, and areas of exposure were obtained and compared between the approaches. An illustrative case is also presented.

RESULTS

The endoscopic transorbital approach (ETOA) exposed the lateral and superior compartments of the CS without obstruction by the internal carotid artery (ICA). The EEA exposed all compartments after mobilizing the ICA. Both approaches enabled similar exposure of the cranial nerves. The depth of surgical corridor was significantly shorter with the ETOA (P < 0.01). The areas of lateral compartment exposure were similar. As the number of instruments placed into the surgical channel increased, the available angles of attack with the ETOA became smaller and were smaller than those of the EEA. In the clinical case presented, the tumor was successfully removed without complications.

CONCLUSIONS

The ETOA has the advantages of a sterile surgical channel, short operation time, little patient trauma, short surgical corridor, large exposure area, and interdural pathway; moreover, it allows dissection through the interdural space without entering the neurovascular compartment of the CS. Although the space for manipulation of instruments is limited, the ETOA is suitable for treating selected tumors in the superior and lateral compartments of the CS.

Learning Curve for Endoscopic Transsphenoidal Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Endoscopic transsphenoidal surgery (ETSS) is emerging as an effective, minimally invasive surgery technique for brain tumors of the pituitary fossa. Using a surgical endoscope, surgeons can obtain a broader, nearer, and more apparent visual field with minimal keyhole entrance. However, ETSS may require a steep learning curve to achieve technical competence and relevant outcomes. Moreover, there is no consensus on the learning process of ETSS. We aimed to review and determine the technical proficiency points of ETSS and discuss how to accelerate the learning curve.

METHODS

Core databases, including PubMed, Embase, and the Cochrane Library, were systematically searched for learning curve studies that demonstrated the clinical outcomes and learning status of ETSS for pituitary adenomas using numerical data. Quality assessments of the included articles were performed using the Newcastle-Ottawa scale. The cutoff points were evaluated based on various outcome measures.

RESULTS

Eleven full-text articles, representing 2780 cases, were selected from 317 screened studies. The outcome measures were operative time, tumor removal, endocrinological results, visual field, and surgical complications. The plateaus or cutoff points in the learning curve varied with a mean of 103 ± 139.43 (range, 9-500) cases.

CONCLUSIONS

ETSS is an efficient and minimally invasive alternative surgical option for pituitary tumors. Plateau points may differ according to outcome measures, patient selection, training status, and surgical conditions. Therefore, great care should be taken when interpreting the learning curve. A systematic training program is essential to improve the learning process of endoscopic neurosurgical procedures.

Surgical Strategies in the Treatment of Giant Pituitary Adenomas

BACKGROUND AND OBJECTIVES

The management of giant pituitary adenomas (GPAs) is challenging due to associated endocrinopathies and the close proximity of these tumors to critical structures, such as the optic nerves, structures of the cavernous sinus, and hypothalamus. The objective of this review article was to summarize the current management strategies for giant pituitary adenomas, including the role of open and endoscopic surgical approaches and the role of medical and radiation therapy in conjunction with surgery.

METHODS

We conducted a retrospective review of GPAs operated at our institute between January 2010 and March 2023. Surgical approaches, extent of resection, and associated complications were documented. Furthermore, we conducted a thorough literature review to identify relevant studies published in the past decade, which were incorporated along with insights gained from our institutional case series of GPAs to analyze and integrate both the existing knowledge base and our institution's firsthand experience in the management of GPAs.

RESULTS

A total of 46 giant pituitary adenomas (GPAs) were operated on, using various surgical approaches. Transsphenoidal approach was used in 25 cases and a staged approach using transsphenoidal and pterional was used in 15 cases. Other approaches included transcortical-transventricular, transcallosal, pterional/orbitozygomatic, and subfrontal approaches. Complications and technical nuances were reported.

CONCLUSION

The management of giant pituitary adenomas remains complex, often involving several modalities-open or endoscopic resection, radiosurgery, and medical management of both the tumor and associated endocrinopathies. Surgical resections are often challenging procedures that require careful consideration of several factors, including patient characteristics, tumor location, and size, and the experience and skill of the surgical team.

Current and Future Perspectives of Microscopic and Endoscopic Transsphenoidal Surgery for Pituitary Adenomas: A Narrative Review

Transsphenoidal resection remains the standard treatment for most pituitary adenomas. However, the ideal surgical approach to safely access these lesions, either microsurgical or endoscopic, continues to be debated. Since the introduction of endoscopic transsphenoidal surgery, centers around the world have increasingly adopted this technique, experiencing a shift away from the conventional microsurgical approach. Large series reporting the efficacy and safety of endoscopic surgery have fueled a growing interest in comparing clinical outcomes between both approaches. Still, proving superiority of either surgical approach remains an elusive task due to the inherent drawbacks of surgical observational studies, as we are still faced with a growing body of evidence reporting conflicting results. Thus, a comprehensive discussion regarding the reach and limitations of both techniques becomes necessary. In this narrative review, we perform a critical appraisal of the literature and provide an expert opinion on the state-of-the-art in transsphenoidal surgery for pituitary adenomas. The advantages and limitations of each approach are assessed and compared from a technical standpoint, and their reported outcomes evaluated in the framework of this transition phase. Available evidence should be interpreted in light of individual patient characteristics and within the context of each medical center, taking into consideration the known impact that surgical expertise and multidisciplinary management hold on clinical outcomes.

The learning curve for endoscopic endonasal pituitary surgery: a systematic review

Recent literature demonstrates that a learning curve exists for endoscopic pituitary surgery. However, there is significant variability in the way these studies report their outcomes. This study aims to systematically review the literature regarding outcomes for endoscopic pituitary surgery and how this may be related to a surgical learning curve. An electronic search of the databases Medline, Scopus, Embase, Web of Science and Cochrane Library databases was performed and data extracted according 2020 Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) statement. Ten articles were included in the review as they examined the following: rates of gross total resection, average operative time, CSF leak rate, visual outcomes, endocrine outcomes and how these results were influenced by surgical experience. We have demonstrated that a learning curve exists for some outcome variables for endoscopic pituitary surgery. However, there is significant heterogeneity in the current body of literature which makes clear comparisons difficult.

Evolution of Surgical Outcomes in Endoscopic Endonasal Resection of Craniopharyngiomas

Introduction  Wide variations exist in the management of craniopharyngiomas, including pituitary stalk preservation/sacrifice. This study examines the practice patterns over 16 years using the endoscopic endonasal approach for the resection of craniopharyngiomas and it examines the effects of stalk preservation. Methods  Retrospective analysis was conducted for 66 patients who underwent endoscopic transsphenoidal surgery for resection of craniopharyngiomas. Patients were stratified into three epochs: 2005 to 2009 ( N  = 20), 2010 to 2015 ( N  = 23), and 2016 to 2020 ( N  = 20), to examine the evolution of surgical outcomes. Subgroup analysis between stalk preservation/stalk sacrifice was conducted for rate of gross total resection, anterior pituitary function preservation, and development of new permanent diabetes insipidus. Results  Gross total resection rates across the first, second, and third epochs were 20, 65, and 52%, respectively ( p  = 0.042). Stalk preservation across epochs were 100, 5.9, and 52.6% ( p  = 0.0001). New permanent diabetes insipidus did not significantly change across epochs (37.5, 68.4, 71.4%; p  = 0.078). Preservation of normal endocrine function across epochs was 25, 0, and 23.8%; ( p  = 0.001). Postoperative cerebrospinal fluid (CSF) leaks significantly decreased over time (40, 4.5, and 0%; [ p  = 0.0001]). Stalk preservation group retained higher normal endocrine function (40.9 vs. 0%; p  = 0.001) and less normal-preoperative to postoperative panhypopituitarism (18.4 vs. 56%; p  = 0.001). Stalk sacrifice group achieved higher GTR (70.8 vs. 28%, p  = 0.005). At last follow-up, there was no difference in recurrence/progression rates between the two groups. Conclusion  There is a continuous evolution in the management of craniopharyngiomas. Gross total resection, higher rates of pituitary stalk and hormonal preservation, and low rates of postoperative CSF leak can be achieved with increased surgical experience.

Navigating the learning curve with large and giant tumors: Initial experience with endoscopic endonasal transphenoidal resection of PitNETs

BACKGROUND

The endoscopic endonasal approach (EEA) has progressively become the preferred choice of surgical intervention for PitNETs. However, the adoption in Sub-Saharan Africa has been low. We report our initial experience with the utility of the EEA in PitNETs particularly in large and giant tumors despite limited resources.

METHODS

The study was over a 73-month period at the University College Hospital, Ibadan, Nigeria. Pre and post-operative clinical, imaging and neuro-ophthalmological findings were documented. Perioperative and postoperative outcomes were recorded. We compared the outcomes between the early 23 and later 22 patients. Data were analyzed using descriptive statistics, student's t test, Mann-Whitney U test and Chi square test at α = 0.05.

RESULTS

There were 45 patients; 25(55.6%) were males. Mean age was 49.9 ± 13.4 years. Visual symptoms predominated with 12(26%) blind in at least one eye. Median tumor volume was 20.9 cm³ and mean tumor diameter was 4.09 ± 0.89 cm. 31(68.9%) had gross or near total excision. Vision improved in 31(68.9%). There were 2 procedure related mortality from CSF leak/meningitis. The mean of the tumor diameter of the earlier patients was less than that of the latter (3.84 vs 4.40 cm, p = 0.04,). The latter group also had more gross or near total resections (26.8% versus 41.5%) but this was not statistically significant. There was no difference in postoperative complications.

CONCLUSIONS

EEA remains a veritable option for PitNETs, including for large and huge tumors, even within resource challenged environments, with acceptable limits of complications.

The learning curve of endoscopic endonasal transsphenoidal surgery for pituitary adenomas with different surgical complexity

Objective

To investigate the learning curve under different surgical complexity in endoscopic transsphenoidal approach for pituitary adenoma.

Methods

273 patients undergoing endoscopic transsphenoidal surgery for pituitary adenoma were collected retrospectively and divided into three groups chronologically (early, middle, and late periods). Surgical complexity was differentiated based on Knosp classification (Knsop grade 0-2 vs. Knosp grade 3-4), tumor maximum diameter (MD) (macroadenomas vs. giant adenomas), and history of previous surgery for pituitary adenoma (first operation vs. reoperation). Then the temporal trends in operative time, surgical outcomes, and postoperative complications were evaluated from early to late.

Results

The median operative time decrease from 169 to 147 min across the three periods (P = 0.001). A significant decrease in operative time was seen in the simple groups [Knosp grade 0-2 adenoma (169 to 137 min, P < 0.001), macroadenoma (166 to 140 min, P < 0.001), and first operation (170.5 to 134 min, P < 0.001)] but not in their complex counterparts (P > 0.05). The GTR rate increased from 51.6% to 69.2% (P = 0.04). The surgical period was an independent factor for GTR in the simple groups [Knosp grade 0-2 adenoma: OR 2.076 (95%CI 1.118-3.858, P = 0.021); macroadenoma: OR = 2.090 (95%CI 1.287-3.393, P = 0.003); first operation: OR = 1.809 (95%CI 1.104-2.966, P = 0.019)] but not in the complex groups. The biochemical cure rate increased over periods without statistical significance (from 37.5% to 56.3%, P = 0.181). Although intraoperative CSF leakage rose (from 20.9% to 35.2%) and postoperative CSF leakage reduced (from 12.1% to 5.5%), there was no statistically significant trend across the three time periods (P > 0.05).

Conclusion

This study showed that complex operations might have a prolonged learning curve. Differentiating surgical difficulty and using multivariate combined analysis may be more helpful in clinical practice.

High fidelity simulation of the endoscopic transsphenoidal approach: Validation of the UpSurgeOn TNS Box

Objective

Endoscopic endonasal transsphenoidal surgery is an established technique for the resection of sellar and suprasellar lesions. The approach is technically challenging and has a steep learning curve. Simulation is a growing training tool, allowing the acquisition of technical skills pre-clinically and potentially resulting in a shorter clinical learning curve. We sought validation of the UpSurgeOn Transsphenoidal (TNS) Box for the endoscopic endonasal transsphenoidal approach to the pituitary fossa.

Methods

Novice, intermediate and expert neurosurgeons were recruited from multiple centres. Participants were asked to perform a sphenoidotomy using the TNS model. Face and content validity were evaluated using a post-task questionnaire. Construct validity was assessed through post-hoc blinded scoring of operative videos using a Modified Objective Structured Assessment of Technical Skills (mOSAT) and a Task-Specific Technical Skill scoring system.

Results

Fifteen participants were recruited of which n = 10 (66.6%) were novices and n = 5 (33.3%) were intermediate and expert neurosurgeons. Three intermediate and experts (60%) agreed that the model was realistic. All intermediate and experts (n = 5) strongly agreed or agreed that the TNS model was useful for teaching the endonasal transsphenoidal approach to the pituitary fossa. The consensus-derived mOSAT score was 16/30 (IQR 14-16.75) for novices and 29/30 (IQR 27-29) for intermediate and experts (p < 0.001, Mann-Whitney U). The median Task-Specific Technical Skill score was 10/20 (IQR 8.25-13) for novices and 18/20 (IQR 17.75-19) for intermediate and experts (p < 0.001, Mann-Whitney U). Interrater reliability was 0.949 (CI 0.983-0.853) for OSATS and 0.945 (CI 0.981-0.842) for Task-Specific Technical Skills. Suggested improvements for the model included the addition of neuro-vascular anatomy and arachnoid mater to simulate bleeding vessels and CSF leak, respectively, as well as improvement in materials to reproduce the consistency closer to that of human tissue and bone.

Conclusion

The TNS Box simulation model has demonstrated face, content, and construct validity as a simulator for the endoscopic endonasal transsphenoidal approach. With the steep learning curve associated with endoscopic approaches, this simulation model has the potential as a valuable training tool in neurosurgery with further improvements including advancing simulation materials, dynamic models (e.g., with blood flow) and synergy with complementary technologies (e.g., artificial intelligence and augmented reality).

Clinical application of the “sellar barrier’s concept” for predicting intraoperative CSF leak in endoscopic endonasal surgery for pituitary adenomas with a machine learning analysis

Background

Recently, it was defined that the sellar barrier entity could be identified as a predictor of cerebrospinal fluid (CSF) intraoperative leakage. The aim of this study is to validate the application of the sellar barrier concept for predicting intraoperative CSF leak in endoscopic endonasal surgery for pituitary adenomas with a machine learning approach.

Methods

We conducted a prospective cohort study, from June 2019 to September 2020: data from 155 patients with pituitary subdiaphragmatic adenoma operated through endoscopic approach at the Division of Neurosurgery, Università degli Studi di Napoli “Federico II,” were included. Preoperative magnetic resonance images (MRI) and intraoperative findings were analyzed. After processing patient data, the experiment was conducted as a novelty detection problem, splitting outliers (i.e., patients with intraoperative fistula, n = 11/155) and inliers into separate datasets, the latter further separated into training (n = 115/144) and inlier test (n = 29/144) datasets. The machine learning analysis was performed using different novelty detection algorithms [isolation forest, local outlier factor, one-class support vector machine (oSVM)], whose performance was assessed separately and as an ensemble on the inlier and outlier test sets.

Results

According to the type of sellar barrier, patients were classified into two groups, i.e., strong and weak barrier; a third category of mixed barrier was defined when a case was neither weak nor strong. Significant differences between the three datasets were found for Knosp classification score (p = 0.0015), MRI barrier: strong (p = 1.405 × 10⁻⁶), MRI barrier: weak (p = 4.487 × 10⁻⁸), intraoperative barrier: strong (p = 2.788 × 10⁻⁷), and intraoperative barrier: weak (p = 2.191 × 10⁻¹⁰). We recorded 11 cases of intraoperative leakage that occurred in the majority of patients presenting a weak sellar barrier (p = 4.487 × 10⁻⁸) at preoperative MRI. Accuracy, sensitivity, and specificity for outlier detection were 0.70, 0.64, and 0.72 for IF; 0.85, 0.45, and 1.00 for LOF; 0.83, 0.64, and 0.90 for oSVM; and 0.83, 0.55, and 0.93 for the ensemble, respectively.

Conclusions

There is a true correlation between the type of sellar barrier at MRI and its in vivo features as observed during endoscopic endonasal surgery. The novelty detection models highlighted differences between patients who developed an intraoperative CSF leak and those who did not.

Effects of a transsphenoidal surgery quality improvement program on patient outcomes and hospital financial performance

OBJECTIVE

A comprehensive quality improvement (QI) program aimed at all aspects of patient care after pituitary surgery was initiated at a single center. This initiative was guided by standard quality principles to improve patient outcomes and optimize healthcare value. The programmatic goal was to discharge most elective patients within 1 day after surgery, improve patient safety, and limit unplanned readmissions. The program is described, and its effect on patient outcomes and hospital financial performance over a 5-year period are investigated.

METHODS

Details of the patient care pathway are presented. Foundational elements of the QI program include evidence-based care pathways (e.g., for hyponatremia and pain), an in-house research program designed to fortify care pathways, patient education, expectation setting, multidisciplinary team care, standard order sets, high-touch postdischarge care, outcomes auditing, and a patient navigator, among other elements. Length of stay (LOS), outcome variability, 30-day unplanned readmissions, and hospital financial performance were identified as surrogate endpoints for healthcare value for the surgical epoch. To assess the effect of these protocols, all patients undergoing elective transsphenoidal surgery for pituitary tumors and Rathke's cleft cysts between January 2015 and December 2019 were reviewed.

RESULTS

A total of 609 adult patients who underwent elective surgery by experienced pituitary surgeons were identified. Patient demographics, comorbidities, and payer mix did not change significantly over the study period (p ≥ 0.10). The mean LOS was significantly shorter in 2019 versus 2015 (1.6 ± 1.0 vs 2.9 ± 2.2 midnights, p < 0.001). The percentage of patients discharged after 1 midnight was significantly higher in 2019 versus 2015 (75.4% vs 15.6%, p < 0.001). The 30-day unplanned hospital readmission rate decreased to 2.8% in 2019 from 8.3% in 2015. Per-patient hospital profit increased 71.3% ($10,613 ± $19,321 in 2015; $18,180 ± $21,930 in 2019), and the contribution margin increased 42.3% ($18,925 ± $19,236 in 2015; $26,939 ± $22,057 in 2019), while costs increased by only 3.4% ($18,829 ± $6611 in 2015; $19,469 ± $4291 in 2019).

CONCLUSIONS

After implementation of a comprehensive pituitary surgery QI program, patient outcomes significantly improved, outcome variability decreased, and hospital financial performance was enhanced. Future studies designed to evaluate disease remission, patient satisfaction, and how the surgeon learning curve may synergize with other quality efforts may provide additional context.

Initial experience in the microsurgical treatment of ruptured brain aneurysms in the endovascular era: characteristics and safety of the learning curve in the first 300 consecutively treated patients

PURPOSE

Currently, there is an increasing tendency to refer only complex aneurysms for microsurgery. The formation of new neurosurgeons dedicated to open vascular neurosurgery becomes challenging in a situation in which complex aneurysms must be dealt with early in the career, raising questions about the safety of the learning curve.

METHODS

We analyzed the characteristics and surgical results of the first 300 consecutively treated patients after subarachnoid hemorrhage by a single neurosurgeon. The incidence of surgical complications and clinical outcomes during the learning curve were analyzed, looking for critical periods regarding patient safety. Microsurgical operative times were also studied.

RESULTS

A high frequency of wide-necked aneurysms was observed (70.3%), and, as a result, large (> 10 mm), MCA and paraclinoid aneurysms were overrepresented. A statistically significant correlation between surgical experience and clinical outcomes was observed, with progressive surgical experience resulting in a lower incidence of unfavorable outcomes. We also observed a higher frequency of major surgical complications, unfavorable clinical outcomes, and lower complete occlusion rates among the first 40 patients. Microsurgical operative times progressively and significantly decreased during the learning curve.

CONCLUSIONS

We observed a high prevalence of wide-necked aneurysms. Young neurosurgeons must be trained and prepared to deal with these aneurysms early in their careers. Although we observed a decrease in unfavorable results with cumulative surgical experience, the first 40 cases were associated with higher rates of major surgical complications, worse clinical outcomes, and lower complete occlusion rates, indicating that this period may be more critical to patient safety.

Volumetric Resection and Complications in Nonfunctioning Pituitary Adenoma by Fully Endoscopic Transsphenoidal Approach along 15 Years of Single-Center Experience

Objective  The aim of this study was to evaluate the rate of complications and the extent of resection (EOR) of nonfunctioning pituitary adenomas by endoscopic endonasal approach (EEA) in a 15-year learning curve. Methods  A total of 100 patients operated by the same surgical team were divided chronologically into two, three, and four groups, comparing differences in EOR measured by a semiautomatic software (Smartbrush, Brainlab), rate of immediate postoperative complications, and the visual and hormonal status at 6 months. Results  There were no significant differences over the years in rates of postoperative complications and in visual status at 6 months. A significant linear correlation between the EOR and the number of surgeries (rho = 0.259, p  = 0.007) was found. The analysis was performed in three groups because of the remarkable differences among them; the EOR were: 87.2% (early group), 93.03% (intermediate group), and 95.1% (late group) ( p  = 0.019). Gross total resection was achieved in 30.3, 51.5, and 64%, respectively ( p  = 0.017); also, the rate of reoperation and the worsening of at least one new hormonal axis were worse in the early group. Consequently, the early group had a higher risk of incomplete resection compared with the late group (odds ratio: 4.2; 95% confidence interval: 1.5-11.7). The three groups were not different in demographic and volume tumor variables preoperatively. Conclusions  The first 33 interventions were associated with a lower EOR, a high volume of residual tumor, a high reoperation rate, and a higher rate of hormonal dysfunction. We did not find differences in terms of postoperative complications and the visual status at 6-month follow-up.

Early outcomes of endoscopic endonasal approach pituitary adenomas resection with minimal nasal injury

To report the results of a consecutive series of pituitary adenomas resected through endoscopic endonasal approach (EEA) with minimal nasal injury.Retrospectively review tumor characteristics and surgical outcomes of a consecutive series of EEA pituitary adenomas resection performed mainly by a single author between March 2018 and June 2019.A total of 75 endoscopic endonasal approach pituitary adenoma resections were performed by the authors' team. Of the 75 patients, 28 through mononostril EEA, 47 through Binonostril EEA. Hadad-Bassagasteguy vascularized nasoseptal flap was harvested in only 4 (5.3%) patients with a high risk of postoperative cerebrospinal fluid leak, and one side middle turbinate only been resected in 2 (2.7%) patients, other patients preserved bilateral middle turbinate. Of the 75 patients, gross total resection is 74.7%, near-total resection is 16.0%. Endocrinological remission was achieved in 76.9% of GH-secreting adenomas, 61.5% of prolactin-secreting adenomas. The postoperative cerebrospinal fluid leak rate was 2.7%. Two patients had suprasellar hemorrhage, 1 patient had perioperative stroke, 2 patients had permanent diabetes insipidus, no cranial nerve deficits, internal carotid artery injury, anosmia, and death. The sino-nasal function was measured with the Sino-Nasal Outcome Test-22 and visual analog scale for olfaction preoperatively and postoperatively, and there was no statistically significant difference.The EEA is an effective approach to resect pituitary adenomas, the gross total resection and near-total resection rate and endocrinological remission rate are satisfactory. The EEA is a safe approach, as the complication rate is acceptable compared with those reported in the previous series of microscopic and endoscopic approaches. These results can be achieved with minimal nasal injury.

Development of a Cadaveric Multiport Model of Posterior Circulation Aneurysm Clipping for Neurosurgery and Otolaryngology Residents

Posterior circulation aneurysms are difficult to treat with the current methods of coiling and clipping. To address limitations in training, we developed a cadaveric model to train learners on endoscopic clipping of posterior circulation aneurysms. An endoscopic transclival approach (ETA) and a transorbital precaruncular approach (TOPA) to successfully access and clip aneurysms of the posterior circulation are described. The model has flexibility in that a colored silicone compound can be injected into the cadaveric vessels for the purpose of training learners on vascular anatomy. The other option is that the model could be connected to a vascular perfusion pump allowing real-time appreciation of a pulsatile or ruptured aneurysm. This cadaveric model is the first of its kind for training of endoscopic clipping of posterior circulation aneurysms. Learners will develop proficiency in endoscopic skills, appropriate dissection, and appreciation for relative anatomy while developing an algorithm that can be employed in a real operative arena. Going forward, various clinical scenarios can be developed to enhance the realism, allow learners from different specialties to work together, and emphasize the importance of teamwork and effective communication.

Endoscopic transsphenoidal surgery for resection of pituitary macroadenoma: A retrospective study

BACKGROUND

The endoscopic transsphenoidal approach is an efficient minimally invasive procedure for removal of pituitary tumors that can be accomplished through a one-hand or two-hand approach. The one-hand procedure through one nostril is more intuitive for surgeons, but maneuvering the instruments can be restrictive. The two-hand procedure using a one-and-half nostril approach provides more precise manipulation. This study aimed to compare the surgical outcomes of one-hand/mono-nostril and two-hand/one-and-half nostril surgeries for resection of large pituitary tumors by a single neurosurgeon.

MATERIALS AND METHODS

The surgical data of 78 consecutive cases with pituitary macroadenoma (diameter >1 cm) were reviewed retrospectively. Altogether, 30 cases received one-hand/mono-nostril surgery, while 48 cases received two-hand/one-and-half nostril surgery. Postoperative outcomes of the two operations were compared.

RESULTS

The operative time, hospital stay, residual rate of pituitary macroadenoma, visual field, surgical complications, and re-operative rates were slightly improved in the two-hand/one-and-half nostril surgery group compared with that in the one-hand/mono-nostril surgery group (all p>0.05). However, postoperative hypopituitarism was less frequent (1/48; 2.0%) with the two-hand/one-and-half nostril approach than with the mono-nostril approach (p = 0.004). Similar surgical outcomes were found in all patients with either small or large pituitary tumors, except that the difference in postoperative improvement in visual field change reached statistical significance (p = 0.044).

CONCLUSION

A single-surgeon endoscopic endonasal transsphenoidal surgery with two-hand/one-and-half nostril approach is an effective and safe procedure for removal of large pituitary tumors.

Ergonomics in Endoscopic Transsphenoidal Surgery: A Survey of the North American Skull Base Society

Objective Different surgical set-ups for endoscopic transsphenoidal surgery (ETS) have been described, but studies on their ergonomics are limited. The aim of this article is to describe present trends in the ergonomics of ETS.

Design and Participants A 33-question, web-based survey was sent to North American Skull Base Society members in 2018 and 116 responded to it (16% of all members). Most respondents were from North America (76%), in academic practice (87%), and neurosurgeons (65%); they had more than 5 years of experience in ETS (73%), had received specific training (66%), and performed at least 5 procedures/mo (55%).

Results Mean reported time for standard and complex procedures were 3.7 and 6.3 hours, respectively. The patient's body is usually positioned in a straight, supine position (84%); the head is in a neutral position (46%) or rotated to the side (38%). Most surgeons perform a binostril technique, work with a partner (95%), and operate standing (94%), holding suction (89%) and dissector (83%); sometimes the endoscope is held by the primary surgeon (22–24%). The second surgeon usually holds the endoscope (72%) and irrigation (42%). During tumor removal most surgeons stand on the same side (65–66%). Many respondents report strain at the dorsolumbar (50%) or cervical (26%) level. Almost one-third of surgeons incorporate a pause during surgery to stretch, and approximately half exercise to be fit for surgery; 16% had sought medical attention for ergonomic-related symptoms.

Conclusion Most respondents value ergonomics in ETS. The variability in surgical set-ups and the relatively high report of complaints underline the need for further studies to optimize ergonomics in ETS.

Endoscopic versus nonendoscopic surgery for resection of pituitary adenomas: a national database study

OBJECTIVE

For symptomatic nonsecreting pituitary adenomas (PAs), resection remains a critical option for treatment. In this study, the authors used a large-population national database to compare endoscopic surgery (ES) to nonendoscopic surgery (NES) for the surgical management of PA.

METHODS

The National Cancer Database was queried for all patients diagnosed with histologically confirmed PA who underwent resection between 2010 and 2016 in which the surgical approach was specified. Due to database limitations, microsurgery and craniotomy were both categorized as NES.

RESULTS

Of 30,488 identified patients, 16,373 (53.7%) underwent ES and 14,115 (46.3%) underwent NES. There was a significant increase in the use of ES over time (OR 1.16, p < 0.01). Furthermore, there was a significant temporal increase in ES approach for tumors ≥ 2 cm (OR 1.17, p < 0.01). Compared to NES, patients who underwent ES were younger (p = 0.01), were treated at academic centers (p < 0.01), lived a greater distance from their treatment site (p < 0.01), had smaller tumors (p < 0.01), had greater medical comorbidity burden (p = 0.04), had private insurance (p < 0.01), and had a higher household income (p < 0.01). After propensity score matching to control for age, tumor size, Charlson/Deyo score, and type of treatment center, patients who underwent ES had a shorter length of hospital stay (LOS) (3.9 ± 4.9 days vs 4.3 ± 5.4 days, p < 0.01), although rates of gross-total resection (GTR; p = 0.34), adjuvant radiotherapy (p = 0.41), and 90-day mortality (p = 0.45) were similar. On multivariate logistic regression, African American race (OR 0.85, p < 0.01) and tumor size ≥ 2 cm (OR 0.89, p = 0.01) were negative predictors of receiving ES, whereas diagnosis in more recent years (OR 1.16, p < 0.01), greater Charlson/Deyo score (OR 1.10, p = 0.01), receiving treatment at an academic institution (OR 1.67, p < 0.01) or at a treatment site ≥ 20 miles away (OR 1.17, p < 0.01), having private insurance (OR 1.09, p = 0.01), and having a higher household income (OR 1.11, p = 0.01) were predictive of receiving ES. Compared to the ES cohort, patients who started with ES and converted to NES (n = 293) had a higher ratio of nonwhite race (p < 0.01), uninsured insurance status (p < 0.01), longer LOS (p < 0.01), and higher rates of GTR (p = 0.04).

CONCLUSIONS

There is an increasing trend toward ES for PA resection including its use for larger tumors. Although ES may result in shorter LOS compared to NES, rates of GTR, need for adjuvant therapy, and short-term mortality may be similar. Factors such as tumor size, insurance status, facility type, income, race, and existing comorbidities may predict receiving ES.

How long is the tail end of the learning curve? Results from 1000 consecutive endoscopic endonasal skull base cases following the initial 200 cases

OBJECTIVE

Endoscopic endonasal approaches (EEAs) to the skull base have evolved over the last 20 years to become an essential component of a comprehensive skull base practice. Many case series show a learning curve from the earliest cases, in which the authors were inexperienced or were not using advanced closure techniques. It is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement. Cases performed during the early steep learning curve were eliminated to examine whether the continued improvement exists over the "tail end" of the curve.

METHODS

A prospectively acquired database of all EEA cases performed by the senior authors at Weill Cornell Medicine/NewYork-Presbyterian Hospital was reviewed. The first 200 cases were eliminated and the next 1000 consecutive cases were examined to avoid the bias created by the early learning curve.

RESULTS

Of the 1000 cases, the most common pathologies included pituitary adenoma (51%), meningoencephalocele or CSF leak repair (8.6%), meningioma (8.4%), craniopharyngioma (7.3%), basilar invagination (3.1%), Rathke's cleft cyst (2.8%), and chordoma (2.4%). Use of lumbar drains decreased from the first half to the second half of our series (p <0.05) as did the authors' use of fat alone (p <0.005) or gasket alone (p <0.005) for dural closure, while the use of a nasoseptal flap increased (p <0.005). Although mean tumor diameter was constant (on average), gross-total resection (GTR) increased from 60% in the first half to 73% in the second half (p <0.005). GTR increased for all pathologies but most significantly for chordoma (56% vs 100%, p <0.05), craniopharyngioma (47% vs 0.71%, p <0.05) and pituitary adenoma (67% vs 75%, p <0.05). Hormonal cure for secreting adenomas also increased from 83% in the first half to 89% in the second half (p <0.05). The rate of any complication was unchanged at 6.4% in the first half and 6.2% in the latter half of cases, and vascular injury occurred in only 0.6% of cases. Postoperative CSF leak occurred in 2% of cases and was unchanged between the first and second half of the series.

CONCLUSIONS

This study demonstrates that contrary to popular belief, the surgical learning curve does not plateau but can continue for several years depending on the complexity of the endpoints considered. These findings may have implications for clinical trial design, surgical education, and patient safety measures.

Transcranial approach as surgical treatment for giant pituitary adenoma during COVID 19 pandemic - What can we learn?: A case report

Introduction

In the COVID 19 pandemic, pituitary surgery is one of challenging surgical treatment, especially the involving transsphenoid approach. It was reported that the aerosolisation and mucosal involvement increase the risk of viral transmission during operation. Therefore, transcranial is a safer surgical approach during COVID-19 pandemic. This study aimed to reported transcranial approach to treat giant pituitary adenoma with aggressive visual disturbance which require urgent surgical management.

Case presentation

We reported a 21-year old male, who required urgent surgery because of progressive visual disturbance due to giant pituitary adenoma. On brain MRI with contrast, it was revealed an extraaxial tumor extending anteriorly over plannum sphenoidal with the greatest diameter was 5.34 cm. Transcranial approach was chosen to resect the tumor. Near total removal of the tumor was achieved without damaging vital neurovascular structure. The visual acuity was improved and no significant postoperative complication. Pathology examination revealed pituitary adenoma.

Conclusion

Transcranial surgery for pituitary adenoma is still an armamentarium in neurosurgical practice, especially in the COVID 19 pandemic to provide safer surgical approach.

Guidelines in the management of CNS tumors

INTRODUCTION

Evidence-based, clinical practice guidelines in the management of central nervous system tumors (CNS) continue to be developed and updated through the work of the Joint Section on Tumors of the Congress of Neurological Surgeons (CNS) and the American Association of Neurological Surgeons (AANS).

METHODS

The guidelines are created using the most current and clinically relevant evidence using systematic methodologies, which classify available data and provide recommendations for clinical practice.

CONCLUSION

This update summarizes the Tumor Section Guidelines developed over the last five years for non-functioning pituitary adenomas, low grade gliomas, vestibular schwannomas, and metastatic brain tumors.

Trends in endoscopic and microscopic transsphenoidal surgery: a survey of the international society of pituitary surgeons between 2010 and 2020

PURPOSE

This comparative survey of surgical practice patterns between 2010 and 2020 aims to elicit trends in practice patterns for transsphenoidal surgery and to identify areas for improvement.

METHODS

Web-based surveys were sent to the International Society of Pituitary Surgeons via a membership listserv in 2010 and 2020. These 33-item surveys collected information on demographics, surgical approach, perceived advantages and disadvantages, and recommendations for improvements. Statistical analyses were conducted using the Mann-Whitney U test for continuous variables and Fisher's exact test for categorical variables.

RESULTS

There were 51 respondents in 2010 and 82 respondents in 2020. The majority were full-time academic surgeons from the United States or Europe. Preference for a purely endoscopic technique increased from 43% in 2010 to 87% in 2020. Preference for routinely working with an otolaryngologist or second neurosurgeon increased from 35 to 51%. Most surgeons (74%) reported that they were more likely to achieve a greater extent of resection with the endoscope, though 51% noted increased operating time. The most commonly rated advantage (34%) of endoscopic TSS was fewer postoperative nasoseptal perforations; the most commonly (34%) rated disadvantage was more postoperative complications, including cerebrospinal fluid leak. Respondents were divided on whether microscopic TSS should continue to be taught in residency. Many (32%) advocated for improved endoscopic instrumentation and team training.

CONCLUSION

Endoscopic TSS is now the clearly preferred method for surgery amongst a cohort of higher-volume academic neurosurgeons. This trend is likely to continue, and this provides guidelines for future training.

Multimaterial and multicolor 3D-printed model in training of transnasal endoscopic surgery for pituitary adenoma

OBJECTIVE

The aim of the present study was to investigate the practical value of a multimaterial and multicolor 3D-printed model in anatomical teaching, surgical training, and preoperative planning of transnasal endoscopic surgery for pituitary adenoma.

METHODS

Multimodality neuroimaging data were obtained in a 42-year-old healthy male volunteer and a 40-year-old female patient with an invasive nonfunctional pituitary adenoma. Three 3D-printed models were produced: a monomaterial and monocolor model, a monomaterial and multicolor model, and a multimaterial and multicolor model. The effects on anatomical teaching and surgical training for exposing the vidian nerve were assessed by 12 residents, and the training effect was validated on cadavers. The practical values for preoperative planning were evaluated by 6 experienced neurosurgeons. All evaluations were based on 5-point Likert questionnaires.

RESULTS

The multimaterial and multicolor model was superior to the monomaterial models in surgical training for exposing the vidian nerve (Fisher test; p < 0.05). In addition, the multimaterial and multicolor model was superior to the monomaterial models in anatomical teaching and preoperative planning (Friedman test; p < 0.05).

CONCLUSIONS

Multimaterial and multicolor 3D printing technology makes it convenient and efficient to produce a practical model for simulating individualized and complex anatomical structures in the sellar region. Furthermore, the multimaterial model can provide a more realistic manipulative experience for surgical training and facilitate the preoperative planning.

The slope of the learning curve in 600 consecutive endoscopic transsphenoidal pituitary surgeries

BACKGROUND

Endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma has become a mainstay of treatment over the last two decades and it is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement.

OBJECTIVE

The objective of this study was to assess the slope of the learning curve over a long period of time for a variety of outcomes measures.

METHODS

We examined outcomes and complications in a consecutive series of 600 EETS for pituitary adenoma grouped into quartiles based on date of surgery.

RESULTS

GTR significantly increased across quartiles from 55 to 79% in the last quartile (p < 0.005). The rate of intraoperative CSF leak significantly decreased from 60% in the first quartile to 33% in the last quartile and the rate of lumbar drain placement from 28% in the first quartile to 6% in the last quartile (p < 0.005). Hormonal remission for secreting adenomas increased from 68% in the first quartile to 90% in the last quartile (p < 0.05). The rate of post-operative CSF leak trended lower (3% in first quartile to 0.7% in last two quartiles). The greatest improvement in outcome occurred between the first and second quartiles (19.9%), but persistent improvement occurred between the second and third (6.7%) and third and fourth quartiles (8.0%).

CONCLUSION

Although the slope of the learning curve is steeper earlier in a surgeon's experience, the slope does not plateau and continues to increase even over more than a decade.

Endonasal endoscopic transsphenoidal approach robot prototype: A cadaveric trial

BACKGROUND

The Endonasal Endoscopic Transsphenoidal Surgery (EETS) is a minimally invasive procedure to approach and remove pituitary tumors and other sellar lesions. The process causes less pain, faster recovery, and provides further minimal invasive access in critical cases. However, a slight deviation of tools from the target area can be fatal to the patients. The aim of this study is to design and develop a prototype robot to demonstrate neurosurgical robot-assisted EET approach.

METHODS

The effectiveness of a prototype robot in executing a minimally invasive EET surgery was studied in 6 cadavers. The robot was associated with a multi-information integrated technique for surgery including QR code tracking. The robot was controlled and driven by the neurosurgeon.

RESULTS

The standard procedure of EET was followed and the robot carried out the first stage of EET under the supervision of neurosurgeon. Finally, the sellar was reached by the neurosurgeon. The result was determined by qualitative analysis and was confirmed by the neurosurgeon. The time for the entire EET surgical procedure showed marked reduction compared to the traditional EET approach.

CONCLUSION

The robot design was found to be technically feasible and hence can be used for assisting the EET procedure. The robot used was able to assist the neurosurgeon correctly to approach the sinus.

Reconstruction of pediatric skull base defects: A retrospective analysis emphasizing the very young

INTRODUCTION

Pathology of the pediatric skull base is rare and ranges from congenital defects to malignancy and traumatic defects. Pediatric patients, particularly those ≤6 years of age, present a unique set of anatomic challenges for the skull base surgeon. The goal of this study was to retrospectively review our experience with reconstruction of pediatric skull base defects with particular emphasis on those ≤6 years of age.

METHODS

A retrospective chart review was conducted of patients ≤20 years of age who underwent endoscopic endonasal and combined endoscopic and open approaches to address cranial base pathology from 2007 to 2018. Patients were divided into two groups; those ≤6 years of age (group A) and those >6 years of age and ≤20 years of age (group B) and reconstructive techniques and outcomes were analyzed.

RESULTS

Intraoperative communication with the subarachnoid space (CSF leak) was created in 50% (3/6) of patients ≤ 6 years of age compared to 32.7% (16/49) in patients > 6 years and ≤20 years of age (P < 0.40) in management of their skull base disease. A vascularized flap was utilized for reconstruction in 66.7% (4/6) of patients ≤ 6 years of age and included a nasoseptal flap in 33.3% (2/6). A vascularized flap was utilized for reconstruction in 38.8% (19/49) of patients > 6 years and ≤20 years of age and most commonly included a nasoseptal flap (22.4%, 11/49). A lumbar drain was utilized in 50% (3/6) of patients ≤ 6 years of age compared to 18.4% (9/49) in patients > 6 and ≤20 years of age (P < 0.08). Post-operative CSF leaks were encountered in 16.7% (1/6) of patients ≤ 6 years of age compared to 10.2% (5/49) in patients > 6 and ≤20 years of age (P < 0.63). Behavioral issues were noted to potentially contribute to failed skull base reconstruction in patients <6 years of age.

CONCLUSIONS

Pediatric patients, particularly those ≤6 years of age, present a unique set of anatomic and behavioral challenges for the skull base surgeon as highlighted in this study.

Challenges, Learning Curve, and Safety of Endoscopic Endonasal Surgery of Sellar-Suprasellar Lesions in a Community Hospital

BACKGROUND AND OBJECTIVE

Endoscopic endonasal surgery (EES) for the management of sellar, suprasellar, and anterior skull base lesions is gaining popularity. Our aim was to analyze and present the clinical outcomes of EES for the management of these lesions in a community hospital setting.

METHODS

We retrospectively reviewed the charts of 56 patients with sellar, suprasellar, and anterior skull base lesions who underwent EES between 2010 and 2018.

RESULTS

There was male predominance (53.6%) with a mean age of 54.9 ± 13.7 years. Lesions were 45 pituitary adenomas, 5 meningiomas, 3 metastatic, 1 craniopharyngioma, 1 Rathke cyst, and 1 mucocele. Gross total excision was achieved in 57.1%, subtotal excision occurred in 37.5%, and decompression and biopsy were achieved in 5.4% patients. Postoperative vision normalized or improved in 27 patients (86.1%) and was stable in 4 patients (13.9%). Recovery of a preexisting hormonal deficit occurred in 13 (23.2%) patients, and a new hormonal deficit occurred in 9 patients (16.1%). The mean hospital stay was 6.1 ± 4.9 days. Postoperative complications included cerebrospinal fluid leak in 8 patients (14.3%). Four patients (7.1%) had meningitis. Diabetes insipidus was present in 19 patients (33.9%), and postoperative intracranial hematoma requiring evacuation was necessary in 2 patients (3.6%). The mean follow-up duration was 47.5 ± 25.8 months. Lesion progression or recurrence requiring redo surgery occurred in 5 patients (8.9%). Regarding the learning curve, the postoperative cerebrospinal fluid leak, meningitis, new hormonal deficits, and diabetes insipidus decreased in the second half of the patients.

CONCLUSIONS

EES provides an effective and safe surgical option with low morbidity and mortality for the treatment of sellar, suprasellar, and anterior skull base lesions in a community hospital setting.

Three-Hand Endoscopic Endonasal Transsphenoidal Surgery: Experience With an Anatomy-Preserving Mononostril Approach Technique

BACKGROUND

Variations on the endoscopic transsphenoidal approach present unique surgical techniques that have unique effects on surgical outcomes, extent of resection (EOR), and anatomical complications.

OBJECTIVE

To analyze the learning curve and perioperative outcomes of the 3-hand endoscopic endonasal mononostril transsphenoidal technique.

METHODS

Prospective case series and retrospective data analysis of patients who were treated with the 3-hand transsphenoidal technique between January 2007 and May 2015 by a single neurosurgeon. Patient characteristics, preoperative presentation, tumor characteristics, operative times, learning curve, and postoperative outcomes were analyzed. Volumetric EOR was evaluated, and a logistic regression analysis was used to assess predictors of EOR.

RESULTS

Two hundred seventy-five patients underwent an endoscopic transsphenoidal surgery using the 3-hand technique. One hundred eighteen patients in the early group had surgery between 2007 and 2010, while 157 patients in the late group had surgery between 2011 and 2015. Operative time was significantly shorter in the late group (161.6 min) compared to the early group (211.3 min, P = .001). Both cohorts had similar EOR (early group 84.6% vs late group 85.5%, P = .846) and postoperative outcomes. The learning curve showed that it took 54 cases to achieve operative proficiency with the 3-handed technique. Multivariate modeling suggested that prior resections and preoperative tumor size are important predictors for EOR.

CONCLUSION

We describe a 3-hand, mononostril endoscopic transsphenoidal technique performed by a single neurosurgeon that has minimal anatomic distortion and postoperative complications. During the learning curve of this technique, operative time can significantly decrease, while EOR, postoperative outcomes, and complications are not jeopardized.

Anatomical Workspace Study of Endonasal Endoscopic Transsphenoidal Approach

Purpose

To determine the workspace through an anatomical dimensional study of the skull base to further facilitate the design of the robot for endonasal endoscopic transsphenoidal (EET) surgery.

Methods

There were 120 cases having a paranasal sinus CT scan in the database. The internal volumes of the nasal cavities (NC), the volumes of the sphenoid sinuses (SS), and the distance between the anterior nasal spine and base of the sellar (d-ANS-BS) were measured.

Results

The Pearson correlation coefficient (PCC) between the relevant distances and the volumes of the right NC was 0.32; between the relevant distances and the volumes of the left NC was 0.43; and between the relevant distances and volumes of NC was 0.41; with a statistically significant difference (p < 0.001). All PCCs had a statistically significant meaningful difference (p < 0.05).

Conclusion

The volume of NCs were significantly correlated with distances (p < 0.05). The safest and shortest distance to guide the robotic arm length in the EET approach could be represented by d-ANS-BS. This result was also used as primary information for further robotic design.

Intra-operative MRI vs endoscopy in achieving gross total resection of pituitary adenomas: a systematic review

BACKGROUND

Intraoperative magnetic resonance imaging (iMRI) is a technology that may improve rates of gross total resection (GTR) for pituitary adenomas. The endoscope is another less expensive technology, which also may maximize resection rates. A direct comparison of these approaches and their additive benefit has never been performed.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standard. PubMed and Embase databases were searched for studies that examined GTR for pituitary adenoma resection with either endoscopic transsphenoidal surgery (eTSS), microscopic transsphenoidal surgery with iMRI (mTSS + iMRI), or endoscopic transsphenoidal surgery with iMRI (eTSS + iMRI).

RESULTS

Eighty-five studies that reported GTR rates in 7124 pituitary adenoma patients were identified. For all pituitary adenomas, eTSS had a pooled proportion of GTR of 68.9% (95% CI 64.7-73.0%) which was similar to that of mTSS + iMRI (GTR 68.3%; 95% CI = 59.4-76.5%) and eTSS + iMRI (GTR 70.7%; 95% CI = 56.9-89.6%). For the subgroup of pituitary macroadenomas, pooled proportions for GTR were similar between eTSS and mTSS + iMRI (eTSS: GTR 59.4%; 95% CI = 49.6-68.7% vs mTSS + iMRI: GTR 68.8%; 95% CI = 57.3-79.3%), and higher for eTSS + iMRI (81.1%; 95% CI = 75.5-86.2%). The post-operative CSF leak proportion for eTSS (4.7%; 95% CI = 3.6-5.9%) was similar to that for eTSS + iMRI (3.7%; 95% CI = 1.6-6.5%) and mTSS + iMRI (4.6%; 95% CI = 2.0-8.3%). No direct statistical comparisons could be performed.

CONCLUSION

Final GTR proportions are similar whether the surgeon uses a microscope supplemented with iMRI or endoscope with or without iMRI. The benefit of the two technologies may be complementary for macroadenomas. These findings are important to consider when comparing the efficacy of different technical strategies in the management of pituitary adenomas.

Carotid Artery Injury during Transsphenoidal Pituitary Surgery: Lessons from a 15-Year Modern Microsurgery Cohort

Background  Internal carotid artery (ICA) injury is a rare but potentially catastrophic complication of transsphenoidal resection (TSR) of pituitary tumors, potentially resulting in a host of deficits due to the risk of hemorrhage, ischemia, or even death. The endoscopic endonasal approach (EEA) has gained considerable popularity in the modern era, with few busy neurosurgeons remaining committed to practicing transnasal pituitary microsurgery. Our objective was therefore to characterize the overall incidence of ICA injury in a large, longitudinal, single-surgeon microscopic TSR series conducted during the modern EEA era. Methods  Retrospective case series. Results  Overall TSR volume by the senior author (F.B.M.) was 817 pituitary tumors during the study period, 2002 to 2017. Within that cohort, two instances of ICA injury were identified (0.2%), including one each with Cushing's disease and acromegaly, both of whom ultimately recovered without residual neurologic deficit. No pediatric injuries were identified. Conclusion  Vascular injury is an exceedingly rare complication of transsphenoidal pituitary surgery. Adjuncts to prevent this complication include careful review of the coronal magnetic resonance imaging, identification of the midline, as needed use of the Doppler, and initial caudal opening of the sellar dura. Although potentially disastrous, good neurologic outcomes may be obtained, with immediate judicious packing followed by immediate digital subtraction angiography to assess vessel patency and secondary complications such as pseudoaneurysm.

Beyond the Learning Curve: Comparison of Microscopic and Endoscopic Incidences of Internal Carotid Injury in a Series of Highly Experienced Operators

BACKGROUND

As the endoscopic endonasal approach (EEA) has gained popularity as an alternative to microsurgery (MS) for transsphenoidal resection (TSR), numerous studies have attempted to assess the differential risk of internal carotid artery (ICA) injury between the techniques, yet results have been equivocal and contradictory. The aim of this study was to evaluate ICA injury in MS versus EEA among highly experienced neurosurgeons.

METHODS

We performed a systematic literature review of publications from 2002-2017 reporting ICA injury outcomes in ≥250 cases using MS or EEA.

RESULTS

Seventeen series reporting 11,149 patients were included: 3 MS series, 13 EEA series, and 1 series with adequate samples for each. ICA injury incidences were 0.0%-1.6% in cohorts of 275-3000. MS series documented 5 ICA injuries in 2672 operations, for an overall incidence of 0.2% (range, 0.0%-0.4%), and EEA series reported 30 ICA injuries in 8477 operations, for a 0.4% injury rate (range, 0.0%-1.6%); the difference was nonsignificant (P = 0.25). Increased operative experience was associated with decreased incidence of ICA injury, a finding preserved in the overall study cohort and within discretely examined MS and EEA subgroups (overall r² = 0.08, MS r² = 0.23, EEA r² = 0.07).

CONCLUSIONS

ICA injury is the most serious complication of TSR of pituitary neoplasms. Operator inexperience may be a more important risk factor than choice of surgical technique, given the comparably low rates of injury obtained by highly experienced surgeons independent of technique. This emphasizes the need for consolidated care in pituitary centers of excellence, improvement of high-fidelity simulators, and skull base mentorship between senior and junior staff.

Complications associated with microscopic and endoscopic transsphenoidal pituitary surgery: experience of 1153 consecutive cases treated at a single tertiary care pituitary center

OBJECTIVE

Pituitary adenomas (PAs) are benign neoplasms that are frequently encountered during workup for endocrinopathy, headache, or visual loss. Transsphenoidal surgery remains the first-line approach for PA resection. The authors retrospectively assessed complication rates associated with transsphenoidal PA resection from an institutional database.

METHODS

A retrospective analysis of 1153 consecutive transsphenoidal pituitary adenoma resections performed at the Keck Hospital of USC between November 1992 and March 2017 was conducted. Microscopic transsphenoidal resection was performed in 85.3% of cases, and endoscopic transsphenoidal resection was performed in 14.7%. Analysis of perioperative complications and patient and tumor risk factors was conducted.

RESULTS

The overall median hospital stay was 3 days. There was 1 perioperative death (0.1%). Surgical complications included postoperative cerebrospinal fluid leak (2.6%), epistaxis (1.1%), postoperative hematoma (1.1%), meningitis (1.0%), cranial nerve paresis (0.8%), hydrocephalus (0.8%), vision loss (0.6%), stroke (0.3%), abdominal hematoma or infection (0.2%), carotid artery injury (0.1%), and vegetative state (0.2%). Perioperative medical complications included bacteremia/sepsis (0.5%), pneumonia (0.3%), myocardial infarction (0.3%), and deep venous thrombosis/pulmonary embolism (0.1%). Endocrine complications were the most frequent, including transient diabetes insipidus (4.3%), symptomatic hyponatremia (4.2%), new hypopituitarism (any axis) (3.6%), permanent diabetes insipidus (0.3%), and adrenal insufficiency (0.2%). There were no significant differences between microscopic and endoscopic approaches with regard to surgical complications (6.4% vs 8.8%, p = 0.247) or endocrine complications (11.4 vs 11.8%, p = 0.888). Risk factors for surgical complications included prior transsphenoidal surgery (11.4% vs 6.8%, p = 0.025), preoperative vision loss (10.3% vs 6.8%, p = 0.002), and presence of PA invasion on MRI (8.5% vs 4.4%, p = 0.007).

CONCLUSIONS

In this single tertiary center study assessing complications associated with transsphenoidal PA resection, the rate of death or major disability was 0.26%. Risk factors for complications included prior surgical treatment and PA invasion. No differences in complication rates between endoscopic and microscopic surgery were observed. When performed at experienced pituitary centers, transsphenoidal surgery for PAs may be performed with a high degree of safety.

Microscopic versus endoscopic transsphenoidal surgery in the Leiden cohort treated for Cushing's disease: surgical outcome, mortality, and complications

BACKGROUND

First-choice treatment for Cushing's disease is transsphenoidal adenomectomy. Since its introduction in the 1970s, many centers have now switched from microscopic to endoscopic surgery. We compared both techniques for the treatment of Cushing's disease at the Leiden University Medical Center, a European reference center for pituitary diseases.

METHODS

Cohort study with inclusion and follow-up of consecutive Cushing's disease patients primarily treated by transsphenoidal surgery at the Leiden University Medical Center between 1978 and 2016. We compared remission rates (primary endpoint), mortality, and complications between microscopic (performed up to 2005) and endoscopic (performed from 2003 onwards) surgery. Subgroup analyses were performed by tumor size, surgical experience, and preoperative imaging techniques. Additionally, surgeons' intraoperative findings regarding presence and removal of the adenoma were related to surgical outcome.

RESULTS

Of 137 included patients, 87 were treated microscopically and 50 endoscopically. Three months after microscopic surgery, 74 patients (86%) were in remission. Five-year recurrence-free survival was 89% (95% confidence interval [CI]: 82-96%), and ten-year recurrence free survival was 84% (95% CI: 75-93%). After endoscopic surgery, 39 patients (83%) were in remission. Both five-year and ten-year recurrence-free survival were 71% (95% CI: 55-87%). Hazard ratio for recurrence was 0.47 (95% CI: 0.19-1.14), and for mortality 2.79 (95% CI: 0.35-22.51), for microscopic versus endoscopic surgery. No learning curve was found for endoscopy, nor an influence of preoperative imaging technique for microscopy. In addition, we did not find a clear relation between the surgeons' intraoperative findings and surgical outcomes.

CONCLUSIONS

This study did not identify a clear advantage of microscopic or endoscopic transsphenoidal surgery for the treatment of Cushing's disease based on clinical outcome. The transition to endoscopic surgery at our center was not accompanied by transient worsening of outcomes, which may be reassuring for those considering transitioning.

Defining the lateral limits of the endoscopic endonasal transtuberculum transplanum approach: anatomical study with pertinent quantitative analysis

OBJECTIVE

The extended endoscopic endonasal transtuberculum transplanum approach is currently used for the surgical treatment of selected midline anterior skull base lesions. Nevertheless, the possibility of accessing the lateral aspects of the planum sphenoidale could represent a limitation for such an approach. To the authors' knowledge, a clear definition of the eventual anatomical boundaries has not been delineated. Hence, the present study aimed to detail and quantify the maximum amount of bone removal over the planum sphenoidale required via the endonasal pathway to achieve the most lateral extension of such a corridor and to evaluate the relative surgical freedom.

METHODS

Six human cadaveric heads were dissected at the Laboratory of Surgical NeuroAnatomy of the University of Barcelona. The laboratory rehearsals were run as follows: 1) preliminary predissection CT scans, 2) the endoscopic endonasal transtuberculum transplanum approach (lateral limit: medial optocarotid recess) followed by postdissection CT scans, 3) maximum lateral extension of the transtuberculum transplanum approach followed by postdissection CT scans, and 4) bone removal and surgical freedom analysis (a nonpaired Student t-test). A conventional subfrontal bilateral approach was used to evaluate, from above, the bone removal from the planum sphenoidale and the lateral limit of the endonasal route.

RESULTS

The endoscopic endonasal transtuberculum transplanum approach was extended at its maximum lateral aspect in the lateral portion of the anterior skull base, removing the bone above the optic prominence, that is, the medial portion of the lesser sphenoid wing, including the anterior clinoid process. As expected, a greater bone removal volume was obtained compared with the approach when bone removal is limited to the medial optocarotid recess (average 533.45 vs 296.07 mm2; p < 0.01). The anteroposterior diameter was an average of 8.1 vs 15.78 mm, and the laterolateral diameter was an average of 18.77 vs 44.54 mm (p < 0.01). The neurovascular contents of this area were exposed up to the insular segment of the middle cerebral artery. The surgical freedom analysis revealed a possible increased lateral maneuverability of instruments inserted in the contralateral nostril compared with a midline target (average 384.11 vs 235.31 mm2; p < 0.05).

CONCLUSIONS

Bone removal from the medial aspect of the lesser sphenoid wing, including the anterior clinoid process, may increase the exposure and surgical freedom of the extended endoscopic endonasal transtuberculum transplanum approach over the lateral segment of the anterior skull base. Although this study represents a preliminary anatomical investigation, it could be useful to refine the indications and limitations of the endoscopic endonasal corridor for the surgical management of skull base lesions involving the lateral portion of the planum sphenoidale.

Secondary pituitary abscess following transsphenoidal surgery with recurrent meningitis: A case report

RATIONALE

The transsphenoidal surgical (TS) approach to sellar masses is the preferred surgical route in most cases. Secondary pituitary abscess (PA) following TS is an extremely rare but serious postoperative complication with potentially high disability and mortality.

PATIENT CONCERNS

We describe an uncommon case of secondary PA in a 42-year-old woman, who underwent uncomplicated transsphenoidal procedures without cerebrospinal fluid leak, to treat primary Rathke cleft cyst. Without obvious cause, the patient suffered recurrent meningitis with complaints of headache, hyperpyrexia, and chills from 1 month after the operation.

DIAGNOSIS

There were no significant imaging findings until a new rim-enhancement lesion was seen in the sellar region on magnetic resonance imaging during the 6th episode of meningitis 11 months after the initial surgery. A diagnosis of secondary PA was considered; INTERVENTIONS:: Therefore, she underwent a 2nd TS with pus evacuation and antibiotic treatment.

OUTCOMES

She improved remarkably and had no recurrence of symptoms during the 9-month follow-up.

LESSONS

Our aim was to present this rare case and discuss the most likely etiologies and preventive measures for this condition. In patients with recurrent meningitis but dormant imaging manifestations after TS, the possibility of secondary PA should considered. Adequate surgical drainage with microbiology-guided antibiotic therapy is the 1st choice for treatment.

Bibliometric Analysis of Journals in the Field of Endoscopic Endonasal Surgery for Pituitary Adenomas

Endoscopic endonasal surgery for pituitary adenomas is being performed more frequently worldwide in the recent years. This first bibliometric analysis was conducted aiming to have a microscopic view of research activities about endoscopic endonasal surgery for pituitary adenomas. The original articles about endoscopic endonasal surgery for pituitary adenomas were extracted from the Web of Science (WoS) and analyzed concerning their distributions. We also explored the potential correlations between publications of different countries and their gross domestic product (GDP) via Pearson correlation test. The total number of original articles retrieved from WoS was 307 from 1997 to 2017. The number of original articles published in the last decade has increased by 530.95% compared with that published in the former decade. The United States has published 124 articles (40.391%), followed by Italy with 40 (13.029%) and Japan with 27 articles (8.795%). The journal that published the highest number of original articles was Journal of Neurosurgery with 31 (10.098%), followed by Neurosurgery (n = 23, 7.492%), World Neurosurgery (n = 23, 7.492%), and Neurosurgical Focus (n = 15, 4.886%). There was a strong correlation between publication numbers and GDP of different countries (r = 0.889, P < 0.001). There is a skyrocket trend of endoscopic endonasal surgery for pituitary adenomas during the last 2 decades, and countries with high GDP tend to make more contributions to this field.

Gross total resection of pituitary adenomas after endoscopic vs. microscopic transsphenoidal surgery: a meta-analysis

BACKGROUND

Microscopic transsphenoidal surgery (mTSS) is a well-established method to address adenomas of the pituitary gland. Endoscopic transsphenoidal surgery (eTSS) has become a viable alternative, however. Advocates suggest that the greater illumination, panoramic visualization, and angled endoscopic views afforded by eTSS may allow for higher rates of gross total tumor resection (GTR). The aim of this meta-analysis was to determine the rate of GTR using mTSS and eTSS.

METHODS

A meta-analysis of the literature was conducted using PubMed, EMBASE, and Cochrane databases through July 2017 in accordance with PRISMA guidelines.

RESULTS

Seventy case series that reported GTR rate in 8257 pituitary adenoma patients were identified. For all pituitary adenomas, eTSS (GTR=74.0%; I² = 92.1%) was associated with higher GTR as compared to mTSS (GTR=66.4%; I² = 84.0%) in a fixed-effect model (P-interaction < 0.01). For functioning pituitary adenomas (FPAs) (n = 1170 patients), there was no significant difference in GTR rate between eTSS (GTR=75.8%; I² = 63.9%) and mTSS (GTR=75.5%; I² = 79.0%); (P-interaction = 0.92). For nonfunctioning pituitary adenomas (NFPAs) (n = 2655 patients), eTSS (GTR=71.0%; I² = 86.4%) was associated with higher GTR as compared to mTSS (GTR=60.7%; I² = 87.5%) in a fixed-effect model (P-interaction < 0.01). None of the associations were significant in a random-effect model (all P-interaction > 0.05). No significant publication bias was identified for any of the outcomes.

CONCLUSION

Among patients who were not randomly allocated to either approach, eTSS resulted in a higher rate of GTR as compared to mTSS for all patients and for NFPA patients alone, but only in a fixed-effect model. For FPA, however, eTSS did not seem to offer a significantly higher rate of GTR. These conclusions should be interpreted with caution because of the nature of the included non-comparative studies.

Preoperative risk factors for postoperative complications in endoscopic pituitary surgery: a systematic review

BACKGROUND

The ability to preoperatively predict postoperative complication risks is valuable for individual counseling and (post)operative planning, e.g. to select low-risk patients eligible for short stay surgery or those with higher risks requiring special attention. These risks however, are not well established in pituitary surgery.

METHODS

We conducted a systematic review of associations between preoperative characteristics and postoperative complications of endoscopic transsphenoidal surgery according to the PRISMA guidelines. Risk of bias was assessed through the QUIPS tool.

RESULTS

In total 23 articles were included, containing 5491 patients (96% pituitary adenoma). There was a wide variety regarding the nature and number of risk factors, definitions, measurement and statistics employed, and overall quality of mainly retrospective studies was low. Consistent significant associations were older age for complications in general, and intraventricular extension for cerebrospinal fluid (CSF) leaks. Associations identified in some but not all studies were younger age, increased BMI, female gender, and learning curve for CSF leaks; increased tumor size for complications in general; and Rathke's cleft cysts for diabetes insipidus. Mortality (incidence rate 1%) was not addressed as a risk factor.

CONCLUSION

Based on current literature, of low to medium quality, it is not possible to comprehensively quantify risk factors for complications. Nevertheless, older age and intraventricular extension were associated with increased postoperative complications. Future research should aim at prospective data collection, reporting of outcomes, and uniformity of definitions. Only then a proper risk analysis can be performed for endoscopic pituitary surgery.

Transsphenoidal pituitary surgery: comparison of two sellar reconstruction techniques and their effect on postoperative cerebrospinal fluid leakage

Transsphenoidal surgery is a common procedure in patients with pituitary adenomas. Several techniques have been previously postulated to achieve sufficient sellar reconstruction to avoid cerebrospinal fluid (CSF) leakage. We analyzed our institutional database concerning two sellar reconstruction techniques and development of postoperative CSF leakage. From 2009 to 2015, 255 patients underwent transsphenoidal pituitary surgery at our institution. According to the technique used for sellar reconstruction, patients were divided into two groups: (1) with muscle patch and fibrin glue and (2) with fibrin glue alone. Postoperative CSF leakage occurred in 7% of the patients. Occurrence of postoperative CSF leakage did not differ significantly between both sellar reconstruction techniques (p = 0.2). Patients who underwent sellar reconstruction with fibrin glue alone had significantly shorter operating time (p < 0.0001), as well as shorter length of hospital stay (p = 0.01). On multivariate analysis, occurrence of intraoperative CSF leakage was the only predictor for postoperative CSF leakage (p < 0.0001). The present data suggests that sellar reconstruction after transsphenoidal pituitary surgery seems to be equally effective in preventing postoperative CSF leakage. However, the use of fibrin glue alone results in shorter hospital stay and operating time without exposing patients to more frequent CSF leakage.

Cumulative sum analysis of the learning curve for endoscopic resection of juvenile nasopharyngeal angiofibroma

BACKGROUND

To determine the learning curve with cumulative sum analysis for endoscopic resection of juvenile nasopharyngeal angiofibroma (JNA) and investigate whether the surgeon's expertise is a risk factor for recurrence.

MATERIALS AND METHODS

We reviewed the medical records of patients with JNA who underwent endoscopic or endoscopic-assisted surgery between 2006 and 2015. We used cumulative sum (Cusum) analysis to plot the learning curve for operation time versus chronological sequence, and verified the Cusum curve by risk-adjusted Cusum (RA-Cusum) analysis. We identified three phases of expertise. The recurrence rate was analyzed using the Kaplan-Meier method and log-rank tests. A multivariable Cox regression analysis was performed to identify the independent risk factors for recurrence.

RESULTS

We included 154 JNA patients with a median age of 16 years. The surgeon overcame the learning curve after case 80 with increasing surgical efficiency and competence. The learning curve plotted by Cusum analysis divided the cases into three phases: phase 1, accumulation of initial experience (cases 1-41); phase 2, further accumulation of experience (cases 42-117); and phase 3, mastering the procedure (cases 118-154). Pearson's χ² tests showed that tumor stage (P = 0.021), blood loss (P = 0.001), operation time (P < 0.001), and phase (P < 0.001) were associated with recurrence. The log-rank test showed that time to recurrence was significantly shorter in phase 1 than in phases 2 and 3. Blood loss and phase were independently prognostic factors for time to recurrence, with P values of 0.023 and 0.009, respectively. The RA-Cusum analysis identified two inflection points of the curve at case 44 and 83, and verified the results of Cusum analysis.

CONCLUSION

Surgical experience and competence with endoscopic resection affect the recurrence rate in JNA patients.

LEVEL OF EVIDENCE

4.