Transnasal-transsphenoidal endoscopic surgery of the pituitary gland

Deep Temporal Muscle Pedicled Flap: A Novel Reconstruction Technique Following Transorbital Approach, Anatomic Study, and Surgical Implications

BACKGROUND AND OBJECTIVES

The temporalis muscle flap has historically been used for repairing defects from orbital procedures and is commonly used in cranial, oral, and facial reconstructions. However, its application for reconstructing the skull base after a transorbital approach has not been explored. Reconstruction after a transorbital intradural approach is still object of preclinical and clinical investigation, with various techniques emerging recently. This study introduces a novel method suitable for extensive resections of the skull base, including intradural resections of the anterior, middle, and posterior cranial fossae.The study aimed to investigate the feasibility of rotating a vascularized myofascial flap from the anterior third of the temporalis muscle onto the skull base, exploring its extension into the middle cranial fossa after drilling the greater wing of the sphenoid.

METHODS

Six endoscopic dissections were performed on formalin-fixed heads to illustrate the feasibility of preparing a deep fascia flap from the temporalis muscle. Red silicone latex was injected into the external carotid artery to confirm the vascular integrity of the deep temporal branches of the maxillary artery.

RESULTS

The deep temporalis myofascial flap offers a large, well-vascularized tissue that can be easily rotated to cover skull base defects after transorbital approaches. Its coverage extends from the middle and anterior cranial fossae to the infratemporal fossa and the lateral wall of the cavernous sinus. It also effectively covers dural defects at the temporal pole.

CONCLUSION

With an appropriate temporal bony window and sufficient exposure, it is feasible to endoscopically prepare a rotation flap from the anterior third of the temporalis muscle, minimizing the need for resecting the lateral orbital margin. This approach is a favorable alternative to traditional reconstruction techniques, offering quick setup in a single operative procedure. Future studies are needed to confirm minimal donor site morbidity regarding masticatory function.

Impact of posterior septectomy on olfaction in endoscopic endonasal transsphenoidal surgery

BACKGROUND

Endoscopic endonasal transsphenoidal surgery is widely used to resect pituitary adenomas, yet its impact on olfactory function after resection of the posterosuperior nasal septum remains a concern. To optimize surgical techniques to preserve olfactory function, it is essential to understand the relationship between the extent of septal resection and olfactory outcomes.

METHODS

This retrospective study analyzed 295 patients who underwent pituitary adenoma surgery. The extent of nasal septum resection was quantified and its impact on olfactory function was assessed using the Cross-Cultural Smell Identification Test (CCSIT), Sino-Nasal Outcome Test-22 (SNOT-22), and a Visual Analog Scale (VAS) for olfactory loss. Preoperative and 6-month postoperative scores were compared to evaluate changes in olfactory function.

RESULTS

There was a significant correlation between larger septal resections and greater reductions in CCSIT scores, indicating a decline in olfactory function. Furthermore, patients with more extensive septal resections reported increased discomfort and olfactory loss, as evidenced by higher SNOT-22 and VAS scores. These findings highlight the importance of the nasal septum in maintaining laminar airflow and its role in olfactory function.

CONCLUSION

Study underscores the adverse effects of extensive posterior septectomy on olfactory outcomes. Minimizing the extent of septal resection may help preserve olfactory function, suggesting a need for surgical strategies that maintain septum integrity to reduce the risk of postoperative olfactory impairment.

Skull base surgery for malignant tumors: The 2nd international collaborative study (1995-2015)

BACKGROUND

The current study presents the effort of a global collaborative group to review the management and outcomes of malignant tumors of the skull base worldwide.

PATIENTS AND METHODS

A total of 28 institutions contributed data on 3061 patients. Analysis evaluated clinical variables, survival outcomes, and multivariable factors associated with outcomes.

RESULTS

The median age was 56 years (IQR 44-67). The open surgical approach was used in 55% (n = 1680) of cases, endoscopic resection was performed in 36% (n = 1087), and the combined approach in 9.6% (n = 294). With a median follow-up of 7.1 years, the 5-year OS DSS and RFS were 65%, 71.7% and 53%, respectively. On multivariable analysis, older age, comorbidities, histology, dural/intracranial involvement, positive margins, advanced stage, and primary site were independent prognostic factors for OS, DSS, and RFS. Adjuvant RT was a protective prognostic factor.

CONCLUSION

The progress across various disciplines may have contributed to improved OS and DSS in this study compared to previous reports.

Outcome of endoscopic transsphenoidal surgery for acromegaly: Comparison of using and not using the floor standing pneumatic powered endoscope-holder system

Introduction

Endoscopic transsphenoidal surgery can be performed by two surgeons, including an endoscopist (PE/2S), and by a single surgeon with an endoscope-holder system (PE/1S + H). We analyzed the surgical outcome, and outcome predictors in acromegaly patients in endoscopic transsphenoidal surgery using floor standing pneumatic endoscope-holder system.

Methods

Endoscopic transsphenoidal surgery was performed with PE/1S+H (n = 51) and PE/2S (n = 20). Postoperative remission was evaluated by the 2010 consensus criteria for acromegaly. We compared the surgical results of PE/2S style and PE/1S+H style, and investigated the factors associated with favorable surgical outcomes.

Results

There was no difference in clinical background between the PE/2S and the PE/1S + H groups. The remission rates for PE/2S and PE/1S+H were 65.0% and 82.4%, respectively, with no significant difference (p = 0.128). In consecutive 71 cases, statistically useful predictors of remission were low preoperative growth hormone (GH) level (<12 ng/mL), low Knosp grade (0-2), and low revised Knosp grade (0-3A). In the conventional Knosp grade 0-2 and 3/4, the sensitivity was 0.76 and the specificity was 0.81. In the revised Knosp grade 0-3A and 3B/4, the sensitivity was 0.96 and the specificity was 0.44.

Conclusion

The outcome of GH-producing pituitary neuroendocrine tumors surgically removed by PE/1S+H could be almost equivalent to that by PE/2S. Preoperative low GH level and Knosp grades, including revised Knosp grades, are useful preoperative predictors for surgical remission of acromegaly.

Long term results with medpor® reconstruction of the anterior skull base at a single institute

OBJECTIVES

To evaluate a technique of multi-layered CSF repair following endonasal anterior skull base surgery using medpor graft.

DESIGN

Retrospective review of consecutive case series from a single centre.

SUBJECTS

68 cases of repair of CSF leaks utilising medpor identified from a larger prospectively maintained database of endonasal endoscopic procedures at our centre.

METHODS

Retrospective review of a database of consecutive anterior skull base cases from 2016-2022, and further data collection from electronic hospital records.

RESULTS

During follow up there were 7 cases of post-op CSF leak (10.3%). There were no radiological complications, and no cases of medpor removal or extrusion. Rates of infection were low, there were 3 (4.4%) cases of confirmed bacterial meningitis within our cohort. The mean length of stay was 4.7 days (median 3 days), with 16 cases discharged on the first post-operative day.

CONCLUSIONS

Our experience of using medpor in anterior skull base reconstruction demonstrates that medpor is a readily available, easily handled, and reliable graft option with relatively low rates of infection and post-op CSF leak. Its use reduces the use of autologous graft materials and the associated donor site morbidity. Our long term follow up data further demonstrates the safety and efficacy of this technique.

A tough bioadhesive hydrogel supports sutureless sealing of the dural membrane in porcine and ex vivo human tissue

Complete sequestration of central nervous system tissue and cerebrospinal fluid by the dural membrane is fundamental to maintaining homeostasis and proper organ function, making reconstruction of this layer an essential step during neurosurgery. Primary closure of the dura by suture repair is the current standard, despite facing technical, microenvironmental, and anatomic challenges. Here, we apply a mechanically tough hydrogel paired with a bioadhesive for intraoperative sealing of the dural membrane in rodent, porcine, and human central nervous system tissue. Tensile testing demonstrated that this dural tough adhesive (DTA) exhibited greater toughness with higher maximum stress and stretch compared with commercial sealants in aqueous environments. To evaluate the performance of DTA in the range of intracranial pressure typical of healthy and disease states, ex vivo burst pressure testing was conducted until failure after DTA or commercial sealant application on ex vivo porcine dura with a punch biopsy injury. In contrast to commercial sealants, DTA remained adhered to the porcine dura through increasing pressure up to 300 millimeters of mercury and achieved a greater maximum burst pressure. Feasibility of DTA to repair cerebrospinal fluid leak in a simulated surgical context was evaluated in postmortem human dural tissue. DTA supported effective sutureless repair of the porcine thecal sac in vivo. Biocompatibility and adhesion of DTA was maintained for up to 4 weeks in rodents after implantation. The findings suggest the potential of DTA to augment or perhaps even supplant suture repair and warrant further exploration.

Endoscopic Anatomy of the Skull Base

Presently, endoscopic skull base surgery has undergone significant advancements since its inception over two decades ago. Nevertheless, it is imperative to underscore that the fundamental basis of all surgical procedures lies in the meticulous understanding of anatomy, with particular emphasis on the ventral anatomy. This facet has recently garnered increased attention.Following the advancements in endoscopic skull base surgery techniques, this chapter will concentrate on the pertinent anatomical considerations that serve as key foundations for successful procedures. These considerations are categorized into two planes: the sagittal plane and the coronal plane.The sagittal plane is further subdivided into five distinct approaches, namely,(1) the transcribriform approach, (2) the transplanum approach, (3) the transsellar approach, (4) the transclival approach, and (5) the transodontoid approach.On the other hand, the coronal plane is delineated into seven specific zones to facilitate comprehension and potential applications: (1) the petrous apex approach, (2) the intrapetrous approach, (3) the suprapetrous approach, (4) the cavernous sinus approach, (5) the infratemporal approach, (6) the medial condyle approach, and (7) the jugular foramen approach.By organizing the anatomical aspects in this systematic manner, the information provided becomes more accessible, fostering a comprehensive understanding of the subject matter for potential future application.

Reconstruction of the Anterior Skull Base Using the Nasoseptal Flap: A Review

The nasoseptal flap is a workhorse reconstructive option for anterior skull base defects during endonasal surgery. This paper highlights the versatility of the nasoseptal flap. After providing a brief historical perspective, this review will focus on the relevant primary literature published in the last ten years. We will touch upon new applications of the flap, how the flap has been modified to expand its reach and robustness, and some of the current limitations. We will conclude by discussing what the future holds for improving upon the design and use of the nasoseptal flap in anterior skull base reconstruction.

Frontiers of Cranial Base Surgery: Integrating Technique, Technology, and Teamwork for the Future of Neurosurgery

The landscape of cranial base surgery has undergone monumental transformations over the past several decades. This article serves as a comprehensive survey, detailing both the historical and current techniques and technologies that have propelled this field into an era of unprecedented capabilities and sophistication. In the prologue, we traverse the historical evolution from rudimentary interventions to the state-of-the-art neurosurgical methodologies that define today's practice. Subsequent sections delve into the anatomical complexities of the anterior, middle, and posterior cranial fossa, shedding light on the intricacies that dictate surgical approaches. In a section dedicated to advanced techniques and modalities, we explore cutting-edge evolutions in minimally invasive procedures, pituitary surgery, and cranial base reconstruction. Here, we highlight the seamless integration of endocrinology, biomaterial science, and engineering into neurosurgical craftsmanship. The article emphasizes the paradigm shift towards "Functionally" Guided Surgery facilitated by intraoperative neuromonitoring. We explore its historical origins, current technologies, and its invaluable role in tailoring surgical interventions across diverse pathologies. Additionally, the digital era's contributions to cranial base surgery are examined. This includes breakthroughs in endoscopic technology, robotics, augmented reality, and the potential of machine learning and AI-assisted diagnostic and surgical planning. The discussion extends to radiosurgery and radiotherapy, focusing on the harmonization of precision and efficacy through advanced modalities such as Gamma Knife and CyberKnife. The article also evaluates newer protocols that optimize tumor control while preserving neural structures. In acknowledging the holistic nature of cranial base surgery, we advocate for an interdisciplinary approach. The ecosystem of this surgical field is presented as an amalgamation of various medical disciplines, including neurology, radiology, oncology, and rehabilitation, and is further enriched by insights from patient narratives and quality-of-life metrics. The epilogue contemplates future challenges and opportunities, pinpointing potential breakthroughs in stem cell research, regenerative medicine, and genomic tailoring. Ultimately, the article reaffirms the ethos of continuous learning, global collaboration, and patient-first principles, projecting an optimistic trajectory for the field of cranial base surgery in the coming decade.

Neuroendoscopy: How We Got Here

From its inception in ancient Egyptian rituals, neuroendoscopy always promised a minimally invasive route to the cerebrum. Early visionaries, however, hit the proverbial wall of technical development until the 20th century, when new technologies allowed for light to be transmitted across a tube for visualization of intracranial structures. Despite a hiccupping start, with surgical microscopy hampering initial excitement, the development and transformation of neuroendoscopy continued, and today it is a widespread and reliable surgical option for the treatment of numerous varied and complex pathologies.

Computer assisted skull base surgery: a contemporary review

Skull base surgery has evolved significantly since Harvey Cushing's first descriptions in the early 1900s. Computer aided surgery (CAS) applications continue to expand; they include virtual surgical planning, augmented and virtual reality, 3D printing of models/cutting guides/implants, surgical navigation, and intraoperative imaging. The authors will review the current skull base CAS literature and propose a computer aided surgical workflow categorizing these applications into 3 phases: 1) Virtual planning, 2) Surgical execution, 3) Intraoperative verification.

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

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

Implementation of a Streamlined Care Pathway to Reduce Cost and Length of Stay for Patients Undergoing Endoscopic Transsphenoidal Pituitary Surgery

BACKGROUND

We implemented a streamlined care pathway for patients undergoing endoscopic transsphenoidal (TSA) pituitary surgery. Select patients are recovered in the postanesthesia care unit and transferred to a step-down unit for intermediate neurologic care (INCU), with clinicians trained to manage cerebrospinal fluid leak, diabetes insipidus (DI), and other complications.

METHODS

We evaluated all TSA surgeries performed at 1 academic medical center from 7th January, 2017 to 30th March, 2020, collecting patient factors, tumor characteristics, cost variables, and outcomes. The INCU pathway was implemented on 7th January 2018. Pathway patients were compared with nonpathway patients across the study period. Outcomes were assessed using multivariate regression, adjusting for patient and surgical characteristics, including intraoperative cerebrospinal fluid leak, postoperative DI, and tumor dimensions.

RESULTS

One hundred eighty-seven patients were identified. Seventy-nine were on the INCU pathway. Mean age was 53.5 years. Most patients were male (66%), privately insured (62%), and white (66%). Mean total cost of admission was $27,276. Mean length of stay (LOS) was 3.97 days. Use of the INCU pathway was associated with total cost reduction of $6376.33 (P < 0.001, 95% confidence interval [CI]: $3698.21-$9054.45) and LOS reduction by 1.27 days (P = 0.008, 95% CI: 0.33-2.20). In-hospital costs were reduced across all domains, including $1964.87 in variable direct labor costs (P < 0.001, 95% CI: $1142.08-$2787.64) and $1206.52 in variable direct supply costs (P < 0.001, 95% CI: $762.54-$1650.51). Pathway patients were discharged earlier despite a higher rate of postoperative DI (25% vs. 11%, P = 0.011), with fewer readmissions (0% vs. 6%, P = 0.021).

CONCLUSIONS

A streamlined care pathway following TSA surgery can reduce in-hospital costs and LOS without compromising patient outcomes.

Endoscopic endonasal approach for infradiaphragmatic craniopharyngiomas: a multicentric Italian study

OBJECTIVE

Infradiaphragmatic craniopharyngiomas (ICs) represent a distinct subtype, harboring a sellar-suprasellar origin and generally growing in the extra-arachnoidal space contained by the diaphragma sellae. They have been considered ideal for surgical removal through the transsphenoidal approach since the 1960s. The authors present a multicentric national study, intending to selectively analyze IC behavior and the impact of the transsphenoidal endoscopic endonasal approach (EEA) on surgical outcomes.

METHODS

Craniopharyngiomas that were intraoperatively recognized as infradiaphragmatic and removed with standard EEA between 2000 and 2021 at 6 Italian neurosurgical departments were included in the study. Clinical, radiological, and surgical findings and outcomes were evaluated and reviewed.

RESULTS

In total, 84 patients were included, with 45.23% identified as pediatric cases and 39.28% as having recurrent tumors. The most common presenting symptoms were endocrine (75%), visual (59.52%), and hypothalamic (26.19%) disorders. ICs were classified as extending below (6 intrasellar and 41 occupying the suprasellar cistern) or above (26 obliterating the anterior recesses of the third ventricle and 11 extending up to the foramina of Monro) the chiasmatic cistern. Gross-total resection (GTR) was achieved in 54 cases (64.28%). Tumor extension above the chiasmatic cistern and calcifications were associated with lower likelihood of GTR. The cumulative rate of postoperative complications was 34.53%, with CSF leak being the most common (14.28%). Endocrine, visual, and hypothalamic functions deteriorated postoperatively in 41/78 patients (52.56%), 5/84 (5.95%), and 14/84 (16.67%), respectively. Twenty-eight patients (33.33%) had recurrence during follow-up (mean 63.51 months), with a mean 5-year progression-free survival (PFS) rate of 58%. PFS was greater in patients who achieved GTR than patients with other extent of resection.

CONCLUSIONS

This is the largest series in the literature to describe ICs removed with standard EEA, without the need for additional bone and dural opening over the planum sphenoidale. EEA provides a direct route to ICs, the opportunity to manage lesions extending up to the third ventricle without breaching the diaphragma, and high rates of GTR and satisfactory clinical outcomes. Increased surgical complexity and morbidity should be expected in patients with extensive suprasellar extension and involvement of the surrounding vital neurovascular structures.

Clinical Applicability of the Sellar Barrier Concept in Patients with Pituitary Apoplexy: Is It Possible?

There is evidence of association between sellar barrier thickness and intraoperative cerebrospinal fluid (CSF) leakage, impacting the postoperative prognosis of the patients. The aim of this study is to analyze the clinical applicability of the sellar barrier concept in a series of operated patients with pituitary apoplexy (PA). A retrospective study was conducted including 47 patients diagnosed with PA who underwent surgical treatment through a transsphenoidal approach. Brain magnetic resonance imaging (MRI) of the patients were evaluated and classified utilizing the following criteria: strong barrier (greater than 1 mm), weak barrier (less than 1 mm), and mixed barrier (less than 1 mm in one area and greater than 1 mm in another). The association between sellar barrier types and CSF leakage was analyzed, both pre- and intraoperatively. The preoperative MRI classification identified 10 (21.28%) patients presenting a weak sellar barrier, 20 patients (42.55%) with a mixed sellar barrier, and 17 patients (36.17%) exhibiting a strong sellar barrier. Preoperative weak and strong sellar barrier subtypes were associated with weak (p ≤ 0.001) and strong (p = 0.009) intraoperative sellar barriers, respectively. Strong intraoperative sellar barrier subtypes reduced the odds of CSF leakage by 86% (p = 0.01). A correlation between preoperative imaging and intraoperative findings in the setting of pituitary apoplexy has been observed.

Surgeon's Eyes on the Relevant Surgical Target

The resolution of the naked eye has been a challenge for the neurosurgical endeavor since the very first attempts of cranial surgery, and advances have been achieved over the centuries, driven by a synergism between the application of emerging technology into the surgical environment and the expansion of the capabilities of neurosurgery. The understanding of the principles of the optical properties of lenses by Abbè (1840-1905) led to the introduction of loupes in the surgical practice, increasing the visual performance during macroscopic procedures. Modern neurosurgery began with the possibility of illumination and magnification of the surgical field as provided by the microscope. Pioneering contributions from Donaghy and Yasargil opened the way to the era of minimalism with reduction of operative corridors and surgical trauma through the adoption of the microsurgical technique. Almost at the same time, engineering mirabilia of Hopkins in terms of optics and lenses allowed for introduction of rigid and flexible endoscopes as a viable tool in neurosurgery. Nowadays, neurosurgeons are aware of and confident using effective and modern tools of visualization in their armamentarium. Herein we present a cogent review of the evolution of visualization tools in neurosurgery, with a special glimpse into the current development and future achievements.

Comparison of the endoscopic endonasal to microscopic sublabial transsphenoidal approach in a case series of pituitary macroadenomas

For a number of years, the microscopic sublabial transsphenoidal (MST) approach was considered the gold standard approach for the treatment of pituitary macroadenomas. Nonetheless, the trend is currently shifting away from the MST to the endonasal transsphenoidal (EET) approach. The aim of the present study was to examine the post-operative outcomes of the first cases operated by a team of two young surgeons using the EET approach, compared to the cases operated by a team of senior neurosurgeons with extensive experience with the MST approach. For this purpose, data from 20 patients with pituitary adenoma were retrospectively collected from a single center who were operated by the current and previous pituitary-surgery teams. All the patients who presented with visual impairment in the EET group recovered completely (5/5), whereas 4/5 patients in the MST group recovered completely. Primary hospitalization duration was similar in the two groups. Gross tumor removal was achieved in 90% of patients in the EET group compared to 70% of the patients operated with the MST technique. Intraoperative complications were comparable between the two groups. The first cases operated at the center with EET proved to have better visual outcomes and a larger tumor removal when compared to the MST group. A greater experience in using this technique could exponentiate the differences in the post-operative outcomes, such as a lower hospitalization duration and fewer intraoperative complications. On the whole, colleagues who have yet to familiarize themselves with the EET approach could perhaps be encouraged to learn to utilize this technique, provided that their center is staffed with an experienced team of skull base surgeons to intervene in an intraoperative complication.

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.

The Prognostic-Based Approach in Growth Hormone-Secreting Pituitary Neuroendocrine Tumors (PitNET): Tertiary Reference Center, Single Senior Surgeon, and Long-Term Follow-Up

Postoperative deserved outcomes in acromegalic patients are to normalize serum insulin-like growth factor (IGF-1), reduce the tumoral mass effect, improve systemic comorbidities, and reverse metabolic alterations. Pituitary neuroendocrine tumors (PitNET) are characterized to present a heterogeneous behavior, and growth hormone (GH)-secreting PitNET is not an exception. Promptly determining which patients are affected by more aggressive tumors is essential to guide the optimal postoperative decision-making process [prognostic-based approach]. From 2006 to 2019, 394 patients affected by PitNET were intervened via endoscopic endonasal transsphenoidal approach by the same senior surgeon. A total of 44 patients that met the criteria to be diagnosed as acromegalic and were followed up at least for 24 months (median of 66 months (26-156) were included in the present study. Multiple predictive variables [age, gender, preoperative GH and IGF-1 levels, maximal tumor diameter, Hardy's and Knosp's grade, MRI. T2-weighted tumor intensity, cytokeratin expression pattern, and clinicopathological classification] were evaluated through uni- and multivariate statistical analysis. Sparse probability of long-term remission was related to younger age, higher preoperative GH and- or IGF-1, group 2b of the clinicopathological classification, and sparsely granulated cytokeratin expression pattern. Augmented recurrence risk was related to elevated preoperative GH levels, tumor MRI T2-weighted hyperintensity, and sparsely granulated cytokeratin expression pattern. Finally, elevated risk for reintervention was related to group 2b of the clinicopathological classification, Knosp's grade IV, and tumor MRI T2-weighted hyperintensity. In this study, the authors determined younger age, higher preoperative GH and- or IGF-1 levels, group 2b of the clinicopathological classification, Knosp's grade IV, MRI T2-weighted tumor hyperintensity and sparsely granulated cytokeratin expression pattern are related to worse postoperative outcomes in long-term follow-up patients affected with GH-secreting PitNET.

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.

Large Pituitary Adenoma: Strategies to Maximize Volumetric Resection Using Endoscopic Endonasal Approaches and an Analysis of Factors Limiting Resection

BACKGROUND

Large pituitary adenomas (LPAs), which constitute ∼5%-14% of all pituitary adenomas, are considered challenging tumors owing to their locally aggressive behavior, low gross total resection rate, and high prevalence of visual deficits and hypopituitarism. We evaluated the utility of various extended endoscopic endonasal approaches in maximizing the resection of LPAs and studied the factors affecting the extent of surgical resection.

METHODS

A retrospective study of all LPAs (defined as a minimum diameter >3 cm and tumor volume >10 cm3) treated via an endoscopic endonasal approach between January 2015 and December 2020 was performed. The volumetric extent of resection (3-dimensional volumetric analysis software) was correlated with various demographic, tumor-related, pathologic, and immunohistochemical factors and its effects on the clinical outcomes studied.

RESULTS

The present study included 106 patients with LPAs. The mean extent of the resection volume was 79.18 ± 21.75 cm3. The factors that affected the extent of resection included the preoperative tumor volume (P = 0.03) and Knosp grade (P = 0.03). The percentage increase in the extent of resection with the use of 2 endonasal corridors was 10.6% and with 3 corridors was 14%. Visual improvement occurred in 82% of patients, and new-onset persistent hormonal insufficiency occurred in 2.9% of patients. Mortality directly related to surgery occurred in 1.8% of cases.

CONCLUSIONS

Extended endoscopic endonasal approaches can safely and effectively be used for gross total resection of LPAs. However, we found that the preoperative tumor volume and Knosp grade were significant factors affecting the extent of tumor resection. The use of multiple endoscopic endonasal corridors can increase the volumetric extent of resection for LPAs.

Indocyanine Green Endoscopy for Pituitary Adenomas with Parasellar Extension: Results from a Preliminary Case Series

BACKGROUND

Advances in visualization tools have brought new confidence, including endoscope-integrated indocyanine (E-ICG), which makes pituitary and skull-base surgery safer and more effective. We report here our preliminary experience with the use of E-ICG to 1) visualize the cavernous segment of the internal carotid artery (ICA); and 2) functionally and anatomically preserve the pituitary gland.

METHODS

A dedicated ICG-integrated endoscope was used in 15 patients with parasellar pituitary adenomas. Indocyanine was administered at 2 different time points during surgery: an early bolus of 12.5 mg at the sphenoid sinus opening to expose the position of the parasellar segment of the ICAs and to identify the position of the normal pituitary gland so that it could be preserved during tumor removal. Subsequently, a second late bolus of 12 mg of ICG was injected to obtain a real-time "wire angiographic" visualization of the flow of the ICAs.

RESULTS

Gross total resection was achieved in 12 cases (80%), whereas subtotal resection was performed in the other 3 cases (20%). The pituitary gland was clearly discernable in 11 cases (91.6%). None of the patients manifested new endocrinologic deficits or major vascular complications.

CONCLUSIONS

E-ICG is a safe and essential aid for pituitary adenomas invading the cavernous sinus. Its performance as a pituitary marker and real-time video angiography showed promising results in terms of extent of resection, endocrinologic outcomes, and prevention of intraoperative complications.

Endoscopic transsphenoidal surgery for non-functioning pituitary adenoma: Learning curve and surgical results in a prospective series during initial experience

Background

To report the initial experience of surgery for non-functioning pituitary adenoma (NFPA) from a neurosurgeon in a dedicated residency training endoscopic transsphenoidal (ETS) program, and detail the surgical and clinical outcomes during this period.

Methods

A prospective series of all patients operated for NFPA, using an ETS approach, during the three first years of experience of a newly board-certified neurosurgeon was analysed. Clinical, radiological and peri-operative data were collected. Extent of resection (EOR) was determined by formal volumetric analysis. Impact of the learning curve and predictive factors of gross total resection (GTR) were determined.

Results

Fifty-three patients with NFPA were included in this prospective cohort which was divided in two periods of time (“First period”: 30 first cases, and “second period”: 23 following cases). Baseline characteristics of the patients in the two periods were similar. Overall occurrence of complication was 22% and was not significantly different in the two periods of time. No patient had severe neurological complication. Gross total resection was achieved in 70% of patients. Mean Extent of resection was 96%. In a multiple linear regression model, a higher EOR was positively correlated with experience (p = 0.018) and negatively correlated with Knosp Score equal to 4 (p < 0.001). Predictive factors for GTR were Higher Knosp grade (p = 0,01), higher pre-operative volume (p = 0.03), and second period of time (p = 0.01).

Conclusion

NFPA surgery can be safe and efficient during the learning period. Dedicated intensive learning, careful patient selection and multidisciplinary work are key to shorten the learning curve and achieve satisfactory results.

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.

Soft Gasket Seal Reconstruction after Endoscopic Endonasal Transtuberculum Resection of Craniopharyngiomas

BACKGROUND

The expanded endoscopic endonasal approach (EEA) is currently well-accepted for a variety of ventral skull base tumors. Such approach often results in a trans-dural defect and intraoperative cerebrospinal fluid (CSF) leak and adequate reconstruction is necessary to prevent postoperative CSF leak and its complications. Reconstruction is usually performed utilizing a variety of materials along with the nasoseptal flap (NSF).

OBJECTIVE

This work's aim is to describe a new reconstructive technique called 'Soft Gasket Seal' (SGS) in detail and compare it with the standard reconstructive technique at our institution for craniopharyngiomas operated via transtuberculum EEA.

METHODS

A retrospective chart review was achieved to identify patients who underwent transtubercular EEA for craniopharyngioma between 2010 and 2018, by the same neurosurgical and otolaryngology team using either the SGS or the standard reconstructive technique.

RESULTS

Of 36 patients who met criteria and were considered for analysis, 15 patients underwent the Soft Gasket Seal reconstruction and 21, the standard reconstruction. There were 16 female (44%) and 20 male (56%) patients. The median age was 42.2±20.9 years. The rate of postoperative CSF leak in the group of patients treated with the standard technique was 14.2%, and 6.6% in the SGS group (OR 0.43 [CI 95% 0.007 - 6.15, p = 0.62).

CONCLUSION

The SGS technique provides a simple reconstructive technique in conjunction with the NSF, showing a tendency of lower complications when compared to our standard technique, while avoiding donor site morbidity. Such results are encouraging, but further studies are necessary to confirm these findings.

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.

Professor Rathke's gift to neurosurgery: the cyst, its diagnosis, surgical management, and outcomes

PURPOSE

Rathke cleft cysts (RCC) are a target for transsphenoidal surgery when symptomatic; however, the surgical techniques and outcomes continue to be of interest. Our goal is to highlight nuances in diagnosis, surgical philosophy and techniques, and outcomes.

METHODS

We retrospectively reviewed a single surgeon experience in a contemporary series of RCC from April 2008 through December 2019. The clinical presentation, radiographic studies, intraoperative findings, histopathological diagnosis, postoperative complications, and outcome data were recorded and analyzed.

RESULTS

A total of 131 endoscopic endonasal operations were performed on 116 patients (30 male, 86 female), with an average age of 39 years. We identified 102 patients without prior surgery, and 14 patients with prior surgery elsewhere. Postoperative complications included transient diabetes insipidus (DI) (n = 23, 20%), permanent DI (n = 5, 4%), SIADH (n = 6, 5%), epistaxis (n = 6, 5%), postoperative infection (n = 3, 2.5%), postoperative CSF leak (n = 1, < 1%), intrasellar hematoma (n = 1, < 1%), and stroke (n = 1, < 1%). Visual improvement was observed in 74% (n = 31/42) of patients presenting with visual loss, and headache improvement in 86% (n = 80/93). Overall, the recurrence rate in our cohort was 11%, with a lower recurrence rate seen in males (p = 0.02). The median follow-up duration was 15.2 months (interquartile range 1.7-52.3) CONCLUSION: Our results reflect the philosophy of a conservative surgical approach, designed to preserve normal pituitary function, and avoid DI, while achieving the maximal feasible resection. Evacuation of the cyst contents and meticulous sampling of the cyst wall when possible for histopathological diagnosis are crucial. The postoperative relief of symptoms and signs is gratifying, as are the overall rates of recurrence and outcomes.

Pituitary Tumor Surgery: Comparison of Endoscopic and Microscopic Techniques at a Single Center

OBJECTIVE

To understand the transition from microscopic surgery (MS) to endoscopic surgery (ES) on the pituitary across the United States, we assessed a single institution practicing both procedures to discern advantages and disadvantages for each.

PATIENTS AND METHODS

Retrospective institutional chart review of 534 patients in a large practice over a 6-year period (January 1, 2014, to December 31, 2019) comparing a single MS neurosurgeon with a single ES neurosurgeon operating on the same days.

RESULTS

In this series, 14% (n=75) of patients had a prior operation, there were no carotid artery injuries, the overall risk for a postoperative infection was 0.4% (n=2), and risk for a postoperative cerebrospinal fluid leak requiring treatment was 2.0% (n=11). Mean ± SD hospital stay was 1.3±0.04 days; readmission for any reason within 30 days occurred in 3.4% (n=18) of patients. The mean volumetric resection for MS was 86.9%±1.7% and for ES was 91.7%±1.3% (P=.03). There was a higher rate of notable events (P=.015) with MS, but MS had 16% lower cost and operative times were 48 minutes shorter than for ES (83±7 vs 131±6 minutes). The ES required substantially fewer postoperative secondary treatments such as radiation therapy (P=.003).

CONCLUSION

Pituitary surgery is a very safe and effective procedure regardless of technique. The MS has shorter operative times and overall lower cost. The ES results in increased volumetric resection and fewer secondary treatments. Both techniques can be valuable to a large practice, and understanding these niches is important when selecting optimal approaches to pituitary surgery for a given patient.

Residual and Recurrent Disease Following Endoscopic Endonasal Approach as a Reflection of Anatomic Limitation for the Resection of Midline Anterior Skull Base Meningiomas

BACKGROUND

Endoscopic endonasal approaches (EEAs) to anterior skull base meningiomas have grown in popularity, though anatomic limitations remain unclear.

OBJECTIVE

To show the anatomic limits of EEA for meningiomas.

METHODS

Retrospective chart review for all patients that underwent EEA for anterior skull base meningiomas from 2005 to 2014.

RESULTS

A total of 100 patients averaged follow-up of 46.9 mo (24-100 mo). A total of 35 patients (35%) had olfactory groove, 33 planum sphenoidale (33%), and 32 tuberculum sella (32%) meningiomas. The average diameter was 2.9 cm (0.5-8.1 cm). Vascular encasement was seen in 11 patients (11%) and calcification in 20 (20%). Simpson Grade 1 (SG1) resection was achieved in 64 patients (64%). Only calcification impacted degree of resection (40% SG1, P = .012). The most common residual was on the anterior clinoid dura (11 patients [11%]). Six (6%) had residual superior/lateral to the optic nerve. Residual tumor was adherent to the optic apparatus or arteries in 5 patients (5%) each, and 3 patients (3%) had residual lateral to the mid-orbit. Rates of residual decreased over time. A total of 11 patients (11%) had tumor recurrence (mean of 40 mo): 4 (4%) on the anterior clinoid, 2 (2%) each on the lateral orbital roof, adherent to optic apparatus and superolateral to the optic nerve, and 1 (1%) was at the anterior falx.

CONCLUSION

Anterior skull base meningiomas can effectively be approached via EEA in most patients; tumors extending to the anterior clinoid, anterior falx, or superolateral to the optic nerve or orbital roof, especially if calcified, may be difficult to reach via EEA.

Footsteps of the Innovations in Rhinology

Rhinology is the study of nose, paranasal sinus, and nasopharynx. The nose is the most prominent structure on the human face and has been a subject of study since ancient human civilization. The history of rhinology has reflected the sociocultural aspects of the times, and rhinology has achieved remarkable growth with innovative discoveries by numerous pioneers. The focus of surgical procedures of the paranasal sinus shifted from mucosal stripping to functional endoscopic surgery with advancement of technology. Furthermore, the field of rhinology is gradually expanding due to cutting-edge technologies such as image-guided surgery, three-dimensional endoscopy, and robotic surgery. Additional clinical experiences and technological developments are expected to further advance rhinology.

Incidence and Management of Delayed Epistaxis Following Endoscopic Skull Base Surgery

Objective:

Among other complications of endoscopic skull base surgery, delayed epistaxis has not been given much importance. This report presents postoperative delayed nosebleed cases in a large number of patients who underwent an endoscopic endonasal transsphenoidal approach to the sellar region for resection of lesions.

Methods:

Three hundred and sixty three patients who were reached to the sellar region by endoscopic endonasal transsphenoidal route and operated was included in the study. Retrospective chart reviewing of these patients was performed. The correlation between the duration of nosebleeds, bleeding location, treatment methods and comorbidities of the patients were evaluated.

Results:

Ten patients (3.6%) reported delayed epistaxis in the postoperative period and were referred to the otolaryngology department. Postoperative epistaxis occurred between days 7^th and 33^th (mean 16.5) days. The treatment consisted of chemical silver nitrate cauterization in two patients, return to the operating room in three patients, nasal packing in five patients.

Conclusion:

Delayed postoperative epistaxis often has no obvious etiology, and intervention requires teamworking. Well-coordinated teamworking of the neurosurgeon with other specialities such as neuroradiology and otorhinolaryngology is needed to achieve better results.

Modern endoscopic skull base neurosurgery

INTRODUCTION

Since the early use of the endoscopic view for treating simple intrasellar pituitary adenomas, the skull base surgery has experienced an unprecedented revolution elevating the treatment of skull base lesions to the next level in proficiency and excellence of care.

METHODS

We have reviewed the preclinical and clinical evidence supporting the use of the endoscope in the treatment of skull base lesions. In this article, we aim to discuss and provide a wide view of the current indications and future perspectives of the endoscopic endonasal approaches (EEA) and of the endoscopic transcranial approaches.

RESULTS

As in the development of any other technique, EEA have gone through a transformation process from theoretical anatomic models to a pragmatic clinical use. Along the way, EEA have required several modifications, as well as pushbacks in the application of this technique in some indications. This process has resulted in the provision of an additional tool to the current surgical armamentarium that allows the skull base surgeon to face most challenging lesions along the skull base.

CONCLUSIONS

The judicious combination of transcranial and endoscopic-transnasal approaches warrants highest chances of achieving satisfactory tumors resection with a reduced risk of complications.

Multilayered Artificial Dura-Mater Models for a Minimally Invasive Brain Surgery Simulator

In this study, new artificial dura-mater models were developed using a multilayered structure of a rubber material (represent an elastic component of a dura-mater) and a fiber sheet (represent fiber component of a dura-mater). The artificial dura-mater models were prepared for use in a brain surgery simulator, especially for transnasal pituitary surgery. The mechanical characteristics of the artificial dura-mater models were tested to check the similarities with porcine dura-mater. Tensile stress, viscoelasticity, and the cutting force generated by microscissors were tested to evaluate the fabricated models. Neurosurgeons also assessed the dura-mater models to evaluate their characteristics. The results indicate that these models made of two different non-woven fiber sheets emulated accurately the actual dura-mater.

Collagen Matrix With Mucoperiosteum Graft as an Effective Fatless Flapless Reconstruction After Endoscopic Pituitary Adenoma Resection

BACKGROUND

Proper skull base reconstruction after endoscopic endonasal pituitary surgery is of great importance to decrease the rate of complications.

OBJECTIVE

To assess the safety and efficacy of reconstruction with materials other than fat graft and naso-septal flaps (NSF) to avoid their associated morbidities.

METHODS

The authors' institutional database for patients who underwent endoscopic endonasal approach for pituitary adenoma was reviewed. Exclusion criteria included recurrence, postradiation therapy, and reconstruction by fat graft or NSF. They were divided into group A, where collagen matrix (CM) (DuraGen® Plus Matrix, Integra LifeSciences Corporation, Plainsboro, New Jersey) alone was used; group B, where CM and simple mucoperiosteum graft were used and group C, which included cases without CM utilization.

RESULTS

The study included 252 patients. No age, gender, or body mass index statistically significant difference between groups. Group B included the largest tumor size (23.0 mm) in comparison to groups A (18.0 mm) and C (13.0 mm). Suprasellar extension was more frequently present (49.4%) in comparison to groups A (29.8%, P = .001) and C (21.2%, P < .001). Postoperative cerebrospinal fluid (CSF) leak rate was 0%, 2.9%, and 6% in groups A, B, and C, respectively. In group B, the CSF leak rate decreased from 45.9% intraoperatively to 2.9% postoperatively (P < .001). In group A, the CSF leak reduction rate was almost statistically significant (P = .06).

CONCLUSION

Utilization of CM and simple mucosperiosteal graft in skull base reconstruction following pituitary adenoma surgery is an effective method to avoid the morbidities associated with NSF or fat graft.

Endoscopic Transnasal Trans-Sphenoidal Approach for Pituitary Adenomas: A Comparison to the Microscopic Approach Cohort by Propensity Score Analysis

BACKGROUND

Despite some evidence for the adoption of endoscopic transnasal trans-sphenoidal surgery (ETSS) for pituitary adenomas, the advantages of this technique over the traditional approach have not been robustly confirmed.

OBJECTIVE

To compare ETSS with the microscopic sublabial trans-septal trans-sphenoidal surgery (MTSS) for pituitary adenomas.

METHODS

We retrospectively reviewed 2 cohorts of ETSS and MTSS performed at our institution from 1995 to 2017. Patient characteristics, surgical data, and outcomes were recorded prospectively. We performed a univariate and multivariable analysis to determine the best surgical approach. To improve the quality of the results, we matched the distribution of patient characteristics between groups by propensity score (PS) method.

RESULTS

A total of 187 procedures (90 MTSS, 97 ETSS) were reviewed. We found better results in the ETSS group in terms of gross total resection (P = .002) and hormone-excess secretion control (P = .014). There was also a lower incidence of cerebrospinal fluid leakage (P = .039), transitory diabetes insipidus (P = .028), and postoperative hypopituitarism (P = .045), as well as a shorter hospital length of stay (P < .001). After PS matching, we confirmed by multivariable logistic regression analysis an increased odds ratio of gross total resection for the ETSS (3.910; 95% CI 1.720-8.889; P = .001).

CONCLUSION

By PS method, our results suggest that the ETSS provides advantages over the traditional MTSS approach for tumor resection. Better control of secreting tumors and a lower rate of most complications also support the selection of the ETSS approach for the treatment of pituitary adenomas.

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

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

The Angelina Dissectors: A Novel Design of Dissectors for Endoscopic Endonasal Approaches

Background  The description and refinement of the transsphenoidal approach would not be possible without new tools and technologies developed by surgeons to facilitate this approach, which is nowadays the standard procedure for more than 90% of sellar lesions. The latest major change in transsphenoidal surgery was the introduction of the rigid endoscope and the subsequent description of the endoscopic endonasal approach. Traditional bayoneted instruments, when used for this technique, were inadequate. New instruments designed, specifically for this technique, are necessary to facilitate the surgeon's work and improve patient outcome. Objective  This study describes a novel design of dissectors created specifically for endoscopic endonasal approaches. Methods  To develop and design the Angelina dissectors, we used our extensive surgical experience to identify the shortcomings of the available dissectors used for transsphenoidal surgery and created the Angelina dissectors. Results  The Angelina dissector was designed with a unique shaft shape which facilitates endoscopic endonasal surgery. Conclusion  Even though an endoscopic endonasal approach is possible using other instruments, the design of these dissectors aids the surgeon's work. It is our impression, based on personal experience that it allows more freedom of movement and dexterity during the procedure, which could translate as an improved patient outcome.

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

BACKGROUND

Post-operative CSF leak is the major source of morbidity following endoscopic transsphenoidal surgery. The purpose of this study was to identify factors associated with post-operative CSF leak in patients undergoing this surgery and facilitate the prospective identification of patients at higher risk of this complication.

METHODS

A review of a prospectively maintained database containing details of 270 endoscopic transsphenoidal operations performed by the senior author over a 9-year period was performed. Univariate analysis was performed using the Chi-squared and Fisher's exact tests, as appropriate. A logistic regression model was constructed for multivariate analysis.

RESULTS

The rate of post-operative CSF leak in this series was 9%. On univariate analysis, previous surgery, resection of craniopharyngiomas, adenomas causing Cushing's disease and intra-operative CSF leaks were associated with an increased risk of post-operative CSF leak. The use of a vascularised nasoseptal flap and increasing surgical experience were associated with a decreased rate of CSF leak. On multivariate analysis, a resection of tumour for Cushing's disease (OR 5.79, 95% CI 1.53-21.95, p = 0.01) and an intra-operative CSF leak (OR 4.56, 95% CI 1.56-13.32, p = 0.006) were associated with an increased risk of post-operative CSF leak. Increasing surgical experience (OR 0.14, 95% CI 0.04-0.46, p = 0.001) was strongly associated with a decreased risk of post-operative CSF leak.

CONCLUSIONS

Increasing surgical experience is a strong predictor of a decreased risk of developing post-operative CSF leak following endoscopic transsphenoidal surgery. Patients with Cushing's disease and those who develop an intra-operative CSF leak should be managed with meticulous skull base repair and close observation for signs of CSF leak post-operatively.

Craniopharyngiomas: experience and results

INTRODUCTION

Craniopharyngiomas are a big challenge in the neurosurgical field. Because these lesions involve important systems, surgeons must weigh the risks of aggressive resection against the long-term challenges of recurrence. We present the outcomes of our patients based on clinical results, degree of resection, recurrence and disease-free survival.

MATERIALS AND METHODS

We reviewed medical records in all patients who had undergone surgical resection for craniopharyngioma at (Hospital Italiano de Buenos Aires) between 2007 and 2019. We considered ophthalmological examinations, imaging studies, endocrinological studies and surgical complications. Radical resections were planned in all of the patients. To help choose the correct surgical approach, craniopharyngiomas were classified based on tumor location.

RESULTS

Thirty cases of craniopharyngioma were analysed. 12.5% were classified as intrasellar, 12.5% as prechiasmatic, 43.75% as retrochiasmatic, and 31.25% as intraventricular. Overall, 38 cases involved a transcranial surgery (15 orbitozygomatic approach; 19 pterional approach and 4 transcallosal approach), seven involved a transsphenoidal approach, two microscopic transnasal approach and one ventricular endoscopy for emptying the craniopharyngioma cyst. Gross-total resection was achieved in 43.7% and near-total resection (more than 90%) in 25%. The mean follow-up period after resection was 4.7 years. Tumor recurrence occurred in 48%, with an average of 42.7 disease-free months.

CONCLUSION

Total tumor resection is the best treatment for craniopharyngioma. Due to its high morbidity and mortality, a multidisciplinary team is necessary for the management of these tumors.

Endoscopic Endonasal Transsphenoidal Surgery: History and Evolution

In previous decades, extensive and disfiguring transfacial and/or transcranial approaches were used to reach the sellar and parasellar areas. However, these surgical routes were burdened by severe complications and high mortality rates. Recently, the development of endoscopic endonasal techniques has revolutionized the surgical strategies for approaching the sella and adjacent areas and increased the development of transsphenoidal surgery. With these techniques, surgeons have been able to overcome the visual limitations of the open surgical approaches and access areas previously hidden from view. After the contributions of the Pittsburgh duo, Carrau and Jho, pioneers of pure endoscopic surgery, our school began to implement this technique, introducing technical innovations and variations, describing the anatomical details and defining new routes, and playing a key role in its widespread clinical application.

Endoscopic subperichondrial transseptal transsphenoidal approach is safe and efficient for non-extended pituitary surgery

PURPOSE

To report the results of a series of patients undergoing the endoscopic subperichondrial transseptal (STRAS) approach for pituitary surgery and to evaluate the efficiency and the safety of this approach.

METHODS

This is a single-centre retrospective study including all patients undergoing pituitary lesion resection through the STRAS approach from January 2002 to December 2017 by a multidisciplinary surgical team (ENT and neurosurgeon). Demographic data, tumour type, complication rate and pre- and post-operative visual, endocrine and tumour status were retrospectively analysed.

RESULTS

119 patients were included in the study, 80 (67%) presenting macroadenoma, 24 (20%) microadenoma (20%) and 6 (5%) giant adenoma. 61 (51%) patients had secreting adenoma and 51 (42%) patient had non-functioning adenoma. The STRAS approach allowed a good visualization of intrasphenoidal and intrasellar anatomical landmarks in all cases and no patient needed turbinate resection. No patient died or had neurological deficit. Endocrine remission or control was achieved in 90.5% of hormone-secreting microadenomas and in 84.2% of hormone-secreting macroadenomas. Gross-total resection was achieved for 39 patients (48.8%) of the 80 macroadenomas. Nasal complication rate was very low, with no septal perforation and two epistaxis (1.7%) medically treated.

CONCLUSION

The STRAS approach is an elegant approach to the sphenoid sinus that enables a good exposure of the intrasphenoidal anatomical landmarks with a maximal preservation of the nasal mucosa. This approach allows an intrasellar work with great comfort and safety for the surgeon using a two-hand or a four-hand technique.

Pituitary Adenomas: What Are the Key Features? What Are the Current Treatments? Where Is the Future Taking Us?

Pituitary tumors are a heterogeneous group of lesions (usually benign) and proper understanding of the anatomy, physiology, and pathology of the hypothalamic/pituitary region is essential to make an accurate diagnosis and define the essential treatment options (i.e., surgery, medical therapies, and radiotherapy, alone or in combination). Surgery is the primary treatment for acromegaly, Cushing disease, thyroid-stimulating hormone-secreting adenomas, resistant prolactinomas, and nonfunctioning pituitary adenomas causing mass effect. Medical and radiation therapy are reserved in cases in which surgery is not possible or does not provide a complete cure. In the last decades, tremendous innovations (i.e., targeted drugs and refined surgical tools and techniques) have expanded the treatment strategies for pituitary adenomas. We herein report the current indications for and depiction of the surgical techniques in pituitary surgery, review current medical treatments, and provide a glimpse of future possibilities.

Endoscopic anatomy of the sellar barrier: From the anatomical model to the operating room

BACKGROUND

The sellar barrier concept reflects the association between the components of the roof of the pituitary fossa and the risk of intraoperative cerebrospinal fluid (CSF) leak in the surgery of pituitary adenomas. We based our concept in previous reports on the microsurgical anatomy of the pituitary fossa's superior wall. However, proof of the usefulness of this concept in endoscopic approaches is yet missing. The aim of this study was to describe the endoscopic anatomy of the sellar barrier and its subtypes in a laboratory setting and to provide evidence of its clinical usefulness.

METHODS

We provided anatomical models in six fresh-frozen head and neck specimens. We performed an endoscopic endonasal approach and recreated a pathological model of each possible subtype of sellar barrier. To demonstrate the usefulness of this model in clinical practice, we conducted a prospective study including all patients with pituitary adenoma operated by an endoscopic approach between June and July 2019.

RESULTS

We successfully recreated the models for each subtype of sellar barrier. When analyzing the clinical cases, we found that intraoperatively, 73.69% (14) had a strong sellar barrier; 21.05% (4) had mixed sellar barrier, and 5.26% (1) had weak sellar barrier. We recorded one case of intraoperative CSF leak in a patient with a weak sellar barrier by magnetic resonance imaging.

CONCLUSION

We described the endoscopic anatomy of the sellar barrier and we recreated the three subtypes in anatomical models. We also identified these subtypes in a series of clinical cases, proving its clinical usefulness.

Endoscopic transsphenoidal approach to skull base lesions. A clinical prospective study

OBJECTIVE

To review the patients operated by endoscopic transphenoidal approach for skull base lesions. All the clinical data including age, gender, type of pathology, surgical outcome and surgical complications were studied.

METHODS

A clinical prospective study was conducted on 94 cases with skull base lesion that were treated in Neuroscience Hospital in Baghdad, Iraq between October 2011 and December 2016. We followed each patient for an average of 2 years after surgery to determine most common lesion involving the skull base, age and gender distribution, surgical outcome, complications and hospital accommodation. Freeze system of Storz all the cases in the study.

RESULTS

The majority of our patients were between the ages of 20-29 years. Among the 94 patients, 67% had macro adenomas, followed by craniopharyngioma 11%. The mortality rate was 2.1%, Gross total removal was 57.4%. All patients show improvement of the headache after surgery, visual improvement was noticed in 73.4% and hospital accommodation was 2-5 days. Three patients developed cerebrospinal fluid leak, Infection meningitis developed in 3 patients 3.1%, and 2 patients (2.1%) suffered from hormonal disorders and were referred to endocrinologist for therapy. Diabetes insipidus developed as a temporary complication in 4 cases (4.2%).

CONCLUSION

Trassphenoidal surgery is relatively safe surgery for properly selected patients.

Development and validation of a preclinical model for training and assessment of cerebrospinal fluid leak repair in endoscopic skull base surgery

BACKGROUND

Achieving an effective endoscopic skull base reconstruction in case of large dural defects requires specific training and can be extremely challenging. The aim of this study was to describe the development and validation of a preclinical model for cerebrospinal fluid (CSF) leak repair, which can be used for training and to test the mechanical efficacy of endoscopic skull base reconstruction.

METHODS

Eleven fresh-frozen cadaver heads were dissected. A catheter was inserted in the subdural space via a cervical access, which was sealed with mastic; a vertical graduated tube connected to the catheter measured intracranial pressure (ICP), while stained water was injected intracranially. After endoscopic skull base reconstruction was performed, an expert surgeon assessed its efficacy. ICP was then gradually increased until a leak was evident and CSF leak pressure value was recorded. The correlation between subjective and quantitative evaluations was investigated through Pearson and Spearman correlation tests.

RESULTS

The model was successfully tested in 11 specimens. A single, large dural defect was created in each model (transplanum-transtuberculum = 4; transplanum-transtuberculum-transsellar = 3; transclival = 3; transcribriform-transplanum = 1). Skull base reconstruction always comprised a rigid buttress with temporal fascia and/or fat. The CSF leak pressure ranged from 4 to 110 cmH₂ O. The correlation between expert subjective and quantitative assessment of skull base reconstruction mechanical efficacy was high (r = 0.7; r_s = 0.7; p = 0.010 and p = 0.006, respectively).

CONCLUSION

This preclinical model is simple, easily reproducible, and effective in simulating an intraoperative leak and objectively measures the CSF leak pressure point of a skull base reconstruction.

A systematic review of effects and complications after transsphenoidal pituitary surgery: endoscopic versus microscopic approach

Background: Microscopic transsphenoidal surgery (MTS) has been considered as the gold standard for transsphenoidal pituitary surgery, but nowadays endoscopic transsphenoidal surgery (ETS) has become popular due to its wide view and improved lighting.Material and methods: The electronic databases were systematically searched, and the meta-analyses of the eligible studies that evaluated endoscopic versus microscopic methods in patients with pituitary surgery were conducted with Review Manager 5.0. The primary outcomes included visual improvement, gross tumor removal (GTR), cerebrospinal fluid (CFS) leak, diabetes insipidus (DI), other complications, and length of hospital stay. The Egger's test was conducted to estimate possible publication bias.Results: In total, 13 articles eventually met the inclusion criteria. The meta-analyses suggested that the differences with regard to visual improvement, overall complication rate, GTR, CSF leak, diabetes insipidus (DI), meningitis, visual impairment, syndrome of inappropriate antidiuretic hormone secretion (SIADH), new onset hypopituitarism, and hypothyroidism between the endoscopic and microscopic groups were not statistically significant. The length of hospital stay was much longer with the microscopic approach when compared with the endoscopic method.Conclusion: The endoscopic and microscopic approaches show similar effects and complication rates. The endoscopic technique could be adopted as a reasonable alternative in pituitary surgery.