Endoscopic pituitary tumor surgery

Recent advances in Otology: Current landscape and future direction

Hearing is an essential sensation, and its deterioration leads to a significant decrease in the quality of life. Thus, great efforts have been made by otologists to preserve and recover hearing. Our knowledge regarding the field of otology has progressed with advances in technology, and otologists have sought to develop novel approaches in the field of otologic surgery to achieve higher hearing recovery or preservation rates. This requires knowledge regarding the anatomy of the temporal bone and the physiology of hearing. Basic research in the field of otology has progressed with advances in molecular biology and genetics. This review summarizes the current views and recent advances in the field of otology and otologic surgery, especially from the viewpoint of young Japanese clinician-scientists, and presents the perspectives and future directions for several topics in the field of otology. This review will aid next-generation researchers in understanding the recent advances and future challenges in the field of otology.

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.

Endonasal endoscopic surgery for pituitary adenomas

Pituitary adenomas are slow-growing, benign intracranial tumors that can be characterized as functional (hormone-producing) or non-functional (non-hormone producing). Symptoms therefore arise from either endocrinologic abnormalities or mass effect on surrounding structures resulting in symptoms such as visual impairment and headache. In the last two decades, technical innovations have shifted surgical resection of such adenomas to endoscopic endonasal approaches. In this review, we describe the evolving approach to pituitary adenomas in the modern endoscopic era, including preoperative multidisciplinary review, relevant surgical anatomy, and a description of the technical nuances of standard and expanded approaches to the anterior skull base.

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.

3-Dimensionally Printed Affordable Nose Model: A Reliable Start in Endoscopic Training for Young Neurosurgeons

BACKGROUND

Training neurosurgical skills is one of the most important tasks of a residency program. Techniques' complexity and pathology rarity define a long learning curve for mastering different surgical skills for which simulation on anatomic samples is extremely important. For this purpose, cadaver laboratory training is the most reliable tool. However, since access to cadaveric specimens is limited, due to costs and availability, surgical skills could be developed using inanimate models. This work aimed to develop a printable 3-dimensional model of the nasal cavity and sellar floor using an open-source downloadable file, to give residents the opportunity to improve their endoscopic surgical skills in a low-risk atmosphere with little cost.

METHODS

The 3D model was realized taking as a sample a real-case CT scan imaging from which the sellar floor was removed. A quail egg was placed underneath the printed model covering the sellar floor opening. Under endoscopic visualization, the "sellar floor" was drilled by each participant with the goal of sparing the egg's inner membrane. Once the task was achieved, surgeons were asked to participate in a satisfaction survey.

RESULTS

The total cost for printing was 6.31€ (6,72$). A satisfaction survey showed technical improvement (90%), increased confidence (80%), and bringing learned skills into the operating room (70%), leading to a 100% agreement in introducing this project into residency programs.

CONCLUSIONS

Training on affordable anatomic models represents a useful tool in technical skills improvement. We believe this model could help residents bring their technical capabilities to more sophisticated levels.

Modified transseptal approach in endoscopic transsphenoidal pituitary surgery

OBJECTIVE

Transsphenoidal pituitary surgery is commonly performed via a direct transostial approach with a posterior septectomy. However, a technique via an endoscopic transseptal route has been described that avoids a posterior septectomy, but it comes with its own disadvantages.

METHODS

This paper describes a modification, and discusses its pros and cons.

RESULTS

The initial incision in the mucosa is placed level with the anterior middle turbinate. The mucoperichondrial flap is raised ipsilaterally until the sphenoid sinus ostium. An incision is made at the osseocartilaginous junction, and the contralateral mucoperichondrial flap is raised. The bony septum and posterior aspect of this flap is excised. The size and position of this window can be adapted. At the end of the operation, the lateralised intact mucoperichondrial flap is moved back to the midline.

CONCLUSION

Excision or deflection of the cartilaginous septum is not required. It maintains an intact septal mucosa on one side and avoids a septal perforation.

The Evolution of Pituitary Gland Surgery from the Ancients to the Millennials

Located at the base of the skull, the pituitary gland has a long and controversial history, not only in terms of its anatomy, but especially in the functions it performs and in the attempt to approach it surgically. Considered by Galen of Pergamon to have a role in releasing waste products of the brain, a theory accepted until the 17th century, the pituitary gland became a separate entity once with the anatomical descriptions of the famous Andreas Vesalius. At the beginning of the 18th century, researches of the time began to be more and more interested in this gland, trying to identify its functions, and at the same time correcting the traditional theories that were wrong or incomplete. Later, they turned their attention to experimental animal studies that represented the germinal nucleus for the transcranial and endoscopic pituitary surgery. In this review, an attempt has been made to record the entire history of anatomy, physiology and surgery of the pituitary gland, from antiquity to the current day's surgical techniques.

Neuroendoscopy: intraventricular and skull base tumor resection in children

During the last 30 years, the neurosurgeons have witnessed a revolution in the practice of interventricular surgery. The advent of neuroendoscopy at the end of the 1980s has allowed a minimally invasive management of a very large series of pathologies in pediatric neurosurgery ranging from hydrocephalus to arachnoid cyst to intraventricular tumors. The progresses in the management of hydrocephalus, intracranial cyst, and the fluid filled collection nevertheless has been more rapid and radical due to the simpler equipment that is necessary to perform this kind of surgery. The intraventricular tumors instead have been addressed in a slower way, and for many years, the only endoscopic procedure that was allowed on interventricular tumors was a biopsy associated with the management of hydrocephalus. Only very small tumors have been considered operable for complete removal during many years due to the limitations of the neuroendoscopic equipment and to the small calibers of the working channel. More recently, the advent of new devices and new surgical techniques are offering new perspectives on the possibility of intraventricular tumor surgery in children. In this review, we describe the historical perspective of the learning curve of intraventricular tumor surgery under neuroendoscopic control and try to offer a view of the future perspective in the removal of larger intraventricular tumors, analyzing the main indications for intraventricular endoscopic tumor surgery. We offer as well an historical perspective of the evolution of skull base surgery and endonasal transsphenoidal approach for skull-based tumors in children. This kind of surgery that has acquired widespread acceptance for many pathologies in adult age has diffused more slowly in pediatric neurosurgery due to the anatomical limitation observed in these age range. Also in this field, the slow evolution of the technique and of the technology available to neurosurgeons has allowed a very significant expansion of indication for the minimally invasive removal of skull base tumors in children.

Treatment of Clival Chordomas: A 20-Year Experience and Systematic Literature Review

Clival chordomas are rare but aggressive skull base tumors that pose significant treatment challenges and portend dismal prognosis. The aim of this study was to highlight the advantages and limitations of available treatments, to furnish prognostic indicators, and to shed light on novel therapeutic strategies. We conducted a retrospective study of clival chordomas that were surgically treated at our institution from 2003 to 2022; for comparison purposes, we provided a systematic review of published surgical series and, finally, we reviewed the most recent advancements in molecular research. A total of 42 patients underwent 85 surgeries; median follow-up was 15.8 years, overall survival rate was 49.9% at 10 years; meanwhile, progression-free survival was 26.6% at 10 years. A significantly improved survival was observed in younger patients (<50 years), in tumors with Ki67 ≤ 5% and when adjuvant radiotherapy was performed. To conclude, clival chordomas are aggressive tumors in which surgery and radiotherapy play a fundamental role while molecular targeted drugs still have an ancillary position. Recognizing risk factors for recurrence and performing a molecular characterization of more aggressive lesions may be the key to future effective treatment.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Trends in Endoscopic and Microscopic Approaches to Transsphenoidal Pituitary Surgery in the US

OBJECTIVES

Among the transsphenoidal (TSS) approaches to pituitary tumors, the microscopic approach (MA) has historically been the predominant technique with the increasing adoption of the endoscopic approach (EA). This study investigates national trends in TSS approaches and postoperative outcomes for MA and EA through 2021.

METHODS

The TriNetX database was queried for patients undergoing TSS (MA and EA) between 2010 and 2021. Data were collected on demographics, geographic distribution of surgical centers, postoperative complications, stereotactic radiosurgery (SRT), repeat surgery, and postoperative emergency department (ED) visits.

RESULTS

8644 TSS cases were queried between 2010 and 2021. MA rates were highest until 2013 when rates of EA (52%) surpassed MA (48%) and continued to increase through 2021 (81%). From 2010 to 2015 EA had higher odds of a postoperative CSF leak (OR 3.40) and diabetes insipidus (DI (OR 2.30)) versus MA (p < 0.05); from 2016 to 2021 differences were not significant. Although there was no significant difference among approaches from 2010 to 2015 for syndrome of inappropriate antidiuretic hormone (SIADH), hyponatremia, or bacterial meningitis, from 2016 to 2021 EA had lower odds of SIADH (OR 0.54) and hyponatremia (OR 0.71), and higher odds of meningitis (OR 1.79) versus MA (p < 0.05). EA had higher odds of additional surgery (either EA or MA) after initial surgery from 2010 to 2021. From 2010 to 2015 EA had lower odds of postoperative SRT compared to MA, whereas in 2016-2021 there was no statistical difference among approaches.

CONCLUSION

This study demonstrates increasing EA adoption for TSS in the United States since 2013. Complication rates have overall improved for EA compared to MA, potentially as a result of improving surgeon familiarity and experience.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2135-2140, 2023.

Incidence, risk factors, management and prevention of severe postoperative epistaxis after endoscopic endonasal transsphenoidal surgery: a single center experience

Objective

Postoperative epistaxis is a very rare but severe complication after endoscopic endonasal transsphenoidal surgery (EETS) that can lead to catastrophic consequences. However, the incidence, risk factors, management and prevention of postoperative epistaxis remain unclear.

Patients and methods

Consecutive patients with pituitary adenoma (PA), Rathke's cleft cyst, craniopharyngioma, or clival chordoma who received EETS in our department between September 2020 and November 2022 were retrospectively analyzed. The incidence, risk factors, management and prevention of postoperative epistaxis were investigated and analyzed.

Results

A total of 557 consecutive patients who received EETS were included in this study. Eight patients (1.4%) (7 PAs and 1 Rathke's cleft cyst) experienced severe postoperative epistaxis. The size of the PAs was 9.6 mm-46.2 mm, with a median size of 22.1 mm. Epistaxis occurred 4 h to 30 days (median 14.5 days) postoperatively. Bleeding was stopped in 3 patients after nasal packing with iodoform gauze. The remaining 5 patients for whom nasal packing was insufficient were all sent to the operating room, and posterior nasal septal artery (PNSA) bleeding was identified and successfully treated with endoscopic bleeding artery electrocauterization under general anesthesia. In the EETS, all 8 patients had downward extension of the septal mucosal incision, in which 6 had intraoperative bleeding of PNSA that were cauterized by bipolar diathermy. Four patients had causative factors, including administration of antiplatelet agents, Valsalva-like manoeuvre, nose blowing and removal of nasal packing, respectively. No patients had recurrent epistaxis during the follow-up period.

Conclusion

Post-EETS epistaxis is a rare but severe complication that could lead to catastrophic consequences, and one of the most common bleeding sources is the PNSA. Endoscopic bleeding artery electrocauterization under general anesthesia may be a safe, economic and effective measure for epistaxis refractory to nasal packing. Avoiding excessive downward extension of the septal mucosal incision could contribute to the prevention of postoperative epistaxis.

Non-functioning pituitary macroadenoma following surgery: long-term outcomes and development of an optimal follow-up strategy

Objectives

Recurrence and regrowth of non-functioning pituitary macroadenomas (NFPMs) after surgery are common but remain unpredictable. Therefore, the optimal timing and frequency of follow-up imaging remain to be determined. We sought to determine the long-term surgical outcomes of NFPMs following surgery and develop an optimal follow-up strategy.

Methods

Patients underwent surgery for NFPMs between 1987 and 2018, with a follow-up of 6 months or more, were identified. Demographics, presentation, management, histology, imaging, and surgical outcomes were retrospectively collected.

Results

In total, 383 patients were included; 256 were men (256/383; 67%) with median follow-up of 8 years. Following primary surgery, 229 patients (229/383; 60%) achieved complete resection. Of those, 28 (28/229; 11%) developed recurrence, including six needed secondary surgery (6/229; 3%). The rate of complete resection improved over time; in the last quartile of cases, 77 achieved complete resection (77/95; 81%). Reoperation-free survival at 5, 10 and 15 years was 99%, 94% and 94%, respectively. NFPMs were incompletely resected in 154 patients (154/383; 40%); of those, 106 (106/154; 69%) had regrowth, and 84 (84/154; 55%) required reoperation. Surgical reintervention-free survival at 5, 10 and 15 years was 74%,49% and 35%, respectively. Young age and cavernous sinus invasion were risk factors for undergoing reoperation (P < 0.001 and P < 0.0001, respectively) and radiotherapy (P = 0.003 and P < 0.001, respectively). Patients with residual tumour required reoperation earlier than those underwent complete resection (P = 0.02). Radiotherapy to control tumour regrowth was delivered to 65 patients (65/383; 17%) after median time of 1 year following surgery. Radiotherapy was administered more in patients with regrowth of residual disease (61/106; 58%) than those who had NFPMs recurrence (4/28; 14%) (P ≤ 0.001) Following postoperative radiotherapy, one patient (1/65; 2%) had evidence of regrowth, seven (7/65; 11%) had tumour regression on imaging, and no patients underwent further surgery.

Conclusions

NFPMs recurrence and regrowth are common, particularly in patients with residual disease post-operatively. We propose a follow-up strategy based on stratifying patients as "low risk" if there is no residual tumour, with increasing scan intervals, or "high risk" if there is a residual tumour, with annual scans for at least five years and extended lifelong surveillance after that.

Staged Strategies to Deal with Complex, Giant, Multi-Fossa Skull Base Tumors

Given the complex and multifaceted nature of resecting giant tumors in the anterior, middle, and, to a lesser extent, the posterior fossa, we present two example strategies for navigating the intricacies of such tumors. The foundational premise of these two approaches is based on a two-stage method that aims to improve the visualization and excision of the tumor. In the first case, we utilized a combined endoscopic endonasal approach and a staged modified pterional, pretemporal, with extradural clinoidectomy, and transcavernous approach to successfully remove a giant pituitary adenoma. In the second case, we performed a modified right-sided pterional approach with pretemporal access and extradural clinoidectomy. This was followed by a transcortical, transventricular approach to excise a giant anterior clinoid meningioma. These cases demonstrate the importance of performing staged operations to address the challenges posed by these giant tumors.

The Party Wall: Redefining the Indications of Transcranial Approaches for Giant Pituitary Adenomas in Endoscopic Era

The evolution of endoscopic trans-sphenoidal surgery raises the question of the role of transcranial surgery for pituitary tumors, particularly with the effectiveness of adjunct irradiation. This narrative review aims to redefine the current indications for the transcranial approaches for giant pituitary adenomas in the endoscopic era. A critical appraisal of the personal series of the senior author (O.A.-M.) was performed to characterize the patient factors and the tumor's pathological anatomy features that endorse a cranial approach. Traditional indications for transcranial approaches include the absent pneumatization of the sphenoid sinus; kissing/ectatic internal carotid arteries; reduced dimensions of the sella; lateral invasion of the cavernous sinus lateral to the carotid artery; dumbbell-shaped tumors caused by severe diaphragm constriction; fibrous/calcified tumor consistency; wide supra-, para-, and retrosellar extension; arterial encasement; brain invasion; coexisting cerebral aneurysms; and separate coexisting pathologies of the sphenoid sinus, especially infections. Residual/recurrent tumors and postoperative pituitary apoplexy after trans-sphenoidal surgery require individualized considerations. Transcranial approaches still have a critical role in giant and complex pituitary adenomas with wide intracranial extension, brain parenchymal involvement, and the encasement of neurovascular structures.

Volumetric measurement of paranasal sinuses and its clinical significance in pituitary neuroendocrine tumors operated using an endoscopic endonasal approach

Objective

Endoscopic endonasal surgery (EES) for deep intracranial lesions has gained popularity following recent developments in endoscopic technology. The operability of invasive pituitary neuroendocrine tumors (PitNETs) depends on the anatomy of the nasal cavity and paranasal sinus. This study aimed to establish a simple volume reconstruction algorithm of the nasal cavity and paranasal sinus. Additionally, this is the first study to demonstrate the relationship between the segmentation method and the clinical significance in patients with PitNET.

Methods

Pre-and postoperative tumor volumes were analyzed in 106 patients with primary (new-onset) PitNETs (80 nonfunctioning and 26 functioning) who underwent EES. The efficiency and accuracy of the semiautomatic segmentation with manual adjustments (SSMA) method was compared with other established segmentation methods for volumetric analysis in the nasal cavity and paranasal sinuses. Correlations between the measured nasal cavity and paranasal sinus volumes and the extent of tumor removal were evaluated.

Results

The SSMA method yielded accurate and time-saving results following the volumetric analyses of nasal cavity and paranasal sinuses with complex structures. Alternatively, the manual and semiautomatic segmentation methods proved time-consuming and inaccurate, respectively. The sphenoid sinus volume measured by SSMA was significantly correlated with the extent of tumor removal in patients with nonfunctioning Knosp grade 3 and 4 PitNET (r = 0.318; p = 0.015).

Conclusion

The volume of sphenoid sinus potentially could predict the extent of resection due to better visualization of the tumor for PitNETs with CS invasion.

The 100 Most Cited Articles in Endoscopic Endonasal Skull Base Surgery: A Bibliometric Analysis

BACKGROUND

The accelerated growth of endoscopic endonasal skull base surgery has led to an abundance of highly cited works that have helped shape the field into its current state. Highlighting these works can serve as a guide for trainees and facilitate evidence-based clinical decision making and operative techniques.

METHODS

Elsevier's Scopus database was used to generate a list of the 100 most cited articles on endoscopic endonasal skull base surgery in September 2022. Results were categorized based on pathology, approach, study design, and study objective. A citation per year analysis was conducted to highlight later publications that may not have had the time to accumulate as many citations as older publications.

RESULTS

The average number of citations for the 100 most cited articles was 210 per article (range 104-1285). Publication dates ranged from 1997 to 2019, with the highest number of articles among the 100 most cited being published in 2008 (15 articles). The journal with the greatest number of publications was Neurosurgery (30 articles). Of the 100 most cited articles, 77 were published between 2000 and 2010. Moreover, 40 of the 100 articles reported surgical outcomes and related complications, and the most common pathology was pituitary adenoma (25 articles).

CONCLUSIONS

This article provides a list of highly influential articles in the field of endoscopic endonasal skull base surgery, highlighting its rapid evolution over the last 3 decades and demonstrating its leap from small descriptive series confined to certain pathologies to larger cohorts exploring possible boundaries and other pathologies.

Guanti bianchi technique for resection of selected pituitary adenomas

Introduction

Since the introduction of the endoscopic endonasal approach (EEA) to skull base, the nasal phase has been a true challenge as it represents the moment of definition of the corridor, thus defining the instruments maneuverability at tumor removal phase. The longstanding cooperation between ENT and neurosurgeons have provided the possibility of creating adequate corridor with maximal respect toward nasal structures and mucosa. This sparked the idea of entering the sella as thieves, so we named "Guanti Bianchi" technique a lesser invasive variation of the approach for the removal of selected pituitary adenoma.

Research Question

The purpose of this study is to present the preliminary results of "Guanti Bianchi" technique.

Material and Methods

Data from 17 patients undergoing "Guanti Bianchi" technique (out of 235 standard EEA) at our center, were retrospectively analysed. ASK Nasal-12, a quality-of-life instrument developed specifically to assess patient perception of nasal morbidity, was administered pre- and postoperatively.

Results

10 (59%) patients were men and 7 (41%) women. The mean age was 67.7 (range 35-88). The average duration of the surgical procedure was 71.17 minutes (range 45-100). GTR was achieved in all patients, no postoperative complications were observed. Baseline ASK Nasal-12 was near normal in all patients, 3/17 (17,6%) experienced transitory very mild symptoms without any worsening at 3 and 6 months.

Discussion and Conclusions

This minimally invasive technique does not require turbinectomy or carving of the nasoseptal flap, it alters the nasal mucosa as little as necessary, and it is quick and easy to perform.

Surgical Approaches to the Third Ventricle: An Update

The third ventricle is located in the deepest part of the brain and is delimited by both telencephalic and diencephalic structures. Its location makes every surgical procedure inside or around it quite challenging, due to the distance from the surface to the fragility of the neurovascular structures that is necessary to dissect before entering its cavity and to the narrow surgical corridors through which it is necessary to work. Its geometric localization inside the cranial cavity and the anatomical relationship with the interhemispheric fissure offers nevertheless to the surgeon an impressive variety of surgical approaches, which allow to reach every millimeter of the third ventricle lumen. Mastering properly all these approaches requires an impressive anatomical knowledge, the best available technology, and most refined technical skills, making the surgery of the third ventricle a point of excellence in the evolution of each neurosurgeon. The development of neuronavigation and neuroendoscopy has been a revolution in neurosurgery in the last 20 years and offered special advantages for the surgery of the third ventricle. In fact, the narrow corridors of approach make the precision of the neuronavigation and the enlightenment and magnification of the neuroendoscopy especially useful to reach the third ventricle cavity and working inside or around it. This chapter reviews the history of the surgery of the third ventricle and offers an update of the variety of surgical corridors identified and of the technology now available to properly work through them and inside the third ventricle cavity.

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.

Endoscopic Endonasal Surgery for Uncommon Pathologies of the Sellar and Parasellar Regions

Endoscopic skull base surgery has become an integral part of the present neurosurgical armamentarium. The pioneering efforts in which the purely endoscopic transsphenoidal approach was introduced have triggered a growing tide of using the endoscopic endonasal procedures for a large variety of skull base lesions. Because of their anatomical peculiarities, lesions of the sellar and parasellar regions lend themselves very well to the endoscopic endonasal approaches. Apart from the common pathological entities, many other less frequent pathologies are encountered in the sellar and parasellar area. In this chapter, we review the surgical technique of the endoscopic endonasal transsphenoidal approach and its extensions applied to a variety of rare and uncommon pathological entities involving the sella turcica and clivus. An overview of these pathological entities is also presented and exemplified.

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.

Predictive value of pituitary tumor morphology on outcomes and complications in endoscopic transsphenoidal surgery

PURPOSE

Endoscopic transsphenoidal surgery (ETSS) is an increasingly utilized approach for resection of pituitary tumors. Prior studies have evaluated preoperative tumor size, location, and extent as prognostic factors for surgical resection. There is little data on the relationship between preoperative pituitary tumor radiographic morphology and surgical outcomes.

STUDY DESIGN

Retrospective longitudinal study.

SETTING

Single tertiary care institution.

SUBJECTS AND METHODS

Preoperative magnetic resonance imaging and computed tomography scans from patients undergoing ETSS for pituitary tumor resections from 2007 to 2017 were retrospectively evaluated. A neuroradiologist classified these pituitary tumors into six morphologic groups, each defined by volume, dimensions, extension, and shape. Surgical difficulty, rates of incomplete resection, and postoperative complications were then stratified in relation to the morphologic groups.

RESULTS

Pituitary tumors from 131 patients were classified from preoperative imaging into six characteristic morphologies: (1) microtumor, (2) round, (3) transverse oblong, (4) superior-inferior oblong, (5) bilobed, and (6) large lobulated. Tumors that were characterized with the large lobulated, bilobed, and transverse oblong morphologies correlated with higher rates of postoperative evidence of residual tumor (70%, 36%, and 47%, respectively, all P < 0.002). Likewise, large lobulated, bilobed, and transverse oblong morphologies were also associated with intraoperative cerebrospinal fluid leaks (70%, 31%, and 35%, respectively, all P < 0.05).

CONCLUSIONS

We describe a novel descriptive system for the morphology of pituitary tumors that can be determined from preoperative imaging. Different tumor morphologic groups are associated with varying degrees of gross tumor resection, complications, and surgical difficulty. Utilizing pituitary tumor morphology may aid surgeons in planning the extent of resection, need for complex closure, and patient counseling.

Historiographies of surgical innovation: endoscopic endonasal pituitary surgery

The historiography of medicine has shifted from narratives of inevitable progress, authored mainly by the medical profession, to a more complex, analytical approach in which historians place medicine in its social context. However, the history of surgery has lagged behind somewhat; Christopher Lawrence suggests this is because the recent focus on the construction of medical knowledge does not incorporate the practical aspects of surgery, which are difficult to extract from their previous linear narrative. Thomas Schlich likewise recognises that surgery is both knowledge and skill-therefore more of a 'craft' than medicine. A possible solution is aligning the history of surgery with the history of technology: analysing the interplay of instruments and human activity.This case study uses the history of endoscopic endonasal pituitary surgery to explore the historiography of surgical innovation, in the context of its heavy reliance on both technology and interdisciplinary divisions of labour. Re-enactment, evolutionary frameworks and using Social Construction of Technology methods all require close collaboration between historian and surgeon to bridge the gap between scholarship and tacit knowledge.

The Current State of Visualization Techniques in Endoscopic Skull Base Surgery

Skull base surgery has undergone significant progress following key technological developments. From early candle-lit devices to the modern endoscope, refinements in visualization techniques have made endoscopic skull base surgery (ESBS) a standard practice for treating a variety of conditions. The endoscope has also been integrated with other technologies to enhance visualization, including fluorescence agents, intraoperative neuronavigation with augmented reality, and the exoscope. Endoscopic approaches have allowed neurosurgeons to reevaluate skull base neuroanatomy from new perspectives. These advances now serve as the foundation for future developments in ESBS. In this narrative review, we discuss the history and development of ESBS, current visualization techniques, and future innovations.

Surgical Planning and Simulation of Endonasal Endoscopic Surgery for Pituitary Adenoma With Cavernous Sinus Invasion

BACKGROUND

Transsphenoidal endoscopic endonasal surgery (EES) provides effective treatment for patients with lesions of the sella turcica. The endoscopic technique requires different instrumentation, which depends on the gross anatomy of the nasal cavity. The treatment of lateral lesions is more challenging in EES.

OBJECTIVE

To evaluate the effect of preoperative simulation using multiple anatomic landmarks.

METHODS

Pre- and postoperative tumor volumes were analyzed in 33 patients with nonfunctioning pituitary adenomas who underwent EES (Knosp grades 3 and 4). The surgical working angle and space were three-dimensionally simulated at the plane of the anterior/posterior surgical field (tuberculum sellae/posterior clinoid process) using multiple anatomic landmarks of high-resolution computed tomography scans, such as nasal piriform aperture (proximal surgical corridor), and the width of bilateral vidian canals or lamina perpendicularis of palatine bone (distal surgical corridor). Receiver operating characteristic curves for the removed tumor volume were used to determine the cutoff value for the simulated working angle and space.

RESULTS

Simulated working space at the plane of tuberculum sellae using piriform aperture and lamina perpendicularis of palatine bone was associated with the removed tumor volume in the cavernous sinus. Patients with a larger working space (≥42.7 mm) significantly showed a higher removed tumor volume ( P = .023). There was no relationship between other parameters and the removed tumor volume.

CONCLUSION

A new method to predict the surgical field for cavernous sinus lesions around sella turcica was successfully established. Further studies are needed to define and expand applications of this simulation method.

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.

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.

Sinonasal Symptoms and Self-Reported Health before and after Endoscopic Pituitary Surgery—A Prospective Study

Objectives Despite the limited invasiveness of endoscopic transsphenoidal surgery (ETSS), some degree of nasal structure destruction is unavoidable. Our objective was to evaluate sinonasal morbidity and self-reported health before and 6 months after ETSS for pituitary tumors, and to identify possible predictive factors for deterioration in sinonasal health.

Design Prospective observational cohort study.

Setting University tertiary referral hospital.

Participants Totally 109 consecutive adult patients undergoing ETSS for pituitary tumors between 2015 and 2019.

Main Outcome Measures Sinonasal symptoms and self-reported health before and 6 months after ETSS, assessed by the Sinonasal Outcome Test (SNOT-22) and the EQ-5D questionnaire. Predictive factors for postoperative deterioration in sinonasal symptoms.

Results The overall SNOT-22 score did not change, but the score of the rhinologic domain of SNOT-22 worsened from 6.0 ± 5.9 before to 8.0 ± 7.4 6 months after surgery (p = 0.011). The EQ-5D visual analog scale improved from 64.0 ± 22.9 before to 71.1 ± 18.7 6 months after surgery (p = 0.00088). Univariate and multivariable regression analyses showed that prior sinonasal surgery was associated with a significant worsening in rhinologic symptoms 6 months after surgery (p = 0.046 and p = 0.020, respectively).

Conclusions Although self-reported overall health improved, significant deterioration of rhinologic symptoms was seen 6 months after ETSS. This information is important for preoperative patient counselling. Further refinement of the surgical technique and follow-up strategies to reduce postoperative sinonasal morbidity could be of value, especially in patients who have undergone prior sinonasal surgery.

A Modified Microscopic-Endoscopic Bilateral Transseptal Approach for Pituitary Adenomas: Comparisons of Nasal Outcome and Quality of Life Using the Microscopic Transnasal Approach

OBJECTIVES

In this study, we introduced a novel modified microscopic-endoscopic bilateral transseptal approach for pituitary adenoma resection to minimize surgery-related nasal injury. We also retrospectively compared comprehensive nasal outcomes and quality of life between the microscopic transnasal approaches.

METHODS

Patients with pituitary adenomas who underwent modified microscopic-endoscopic bilateral transseptal or microscopic transnasal approaches were assessed for olfactory function and quality of life using the Sniffin' Sticks test, the Sino-Nasal Outcome Test-22 (SNOT-22), the SF-36, the anterior skull base (ASK) nasal inventory, and the subjective visual analog scale (VAS) before and 1 and 3 months after surgery. A nasal endoscopy procedure was also performed to evaluate structure abnormalities at 1 and 3 months after surgery.

RESULTS

Fifty-eight patients who underwent either modified microscopic-endoscopic bilateral transseptal (35 patients) or microscopic transnasal (23 patients) surgery were consecutively enrolled. Patients who underwent either transnasal approach experienced similar surgical complications, except for intraoperative cerebrospinal fluid leakage (43.5% vs 14.3% for modified microscopic-endoscopic bilateral transseptal or microscopic transnasal approach, respectively; p = 0.013). Patients who underwent the two approaches fully recovered according to the SF-36, SNOT-22, VAS, and Sniffin' Sticks surveys, but not ASK scores, 3 months post-operatively. There was no significant difference in nasal endoscopy outcome at 3 months follow-up between the two approaches.

CONCLUSIONS

The modified microscopic-endoscopic bilateral transseptal approach showed largely similar nasal mucosa protective outcomes to those of the microscopic transnasal approach for pituitary adenoma surgery. After pituitary adenoma resection using the modified approach, patients' postoperative olfactory function, nasal structure, and quality of life can be restored to preoperative status within 3 months.

Endoscopic vs. Microscopic Transsphenoidal Surgery for the Treatment of Pituitary Adenoma: A Meta-Analysis

Purpose

Currently, endoscopic transsphenoidal surgery (ETS) and microscopic transsphenoidal surgery (MTS) are commonly applied treatments for patients with pituitary adenomas. This meta-analysis was conducted to evaluate the efficacy and safety of ETS and MTS for these patients.

Methods

A computer search of Pubmed, Embase, Cochrane library, Web of Science, and Google Scholar databases was conducted for studies investigating ETS and MTS for patients with pituitary adenomas. The deadline is March 01, 2021. RevMan5.1 software was used to complete this meta-analysis after literature screening, data extraction, and literature quality evaluation.

Results

A total of 37 studies including 5,591 patients were included. There was no significant difference in gross tumor removal (GTR) and hormone-excess secretion remission (HES remission) between two groups [RR = 1.10, 95% CI (0.99–1.22), P = 0.07; RR = 1.09, 95% CI (1.00–1.20), P = 0.05]. ETS was associated with lower incidence of diabetes insipidus (DI) [RR = 0.71, 95% CI (0.58–0.87), P = 0.0008], hypothyroidism [RR = 0.64, 95% CI (0.47–0.89), P = 0.007], and septal perforation [RR = 0.32, 95% CI (0.13–0.79), P = 0.01] than those with MTS.

Conclusion

This meta-analysis indicated that ETS cannot significantly improve GTR and HES remission. However, ETS could reduce the incidence of DI, hypothyroidism, and septal perforation without increasing the rate of other complications.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/#myprospero, identifier: CRD42021241217.

Utilizing a Novel Pituitary Retractor for Early Descent of the Diaphragma Sellae during Endoscopic Transsphenoidal Pituitary Surgery

Objective

Early descent of the diaphragm sellae (DS) during endoscopic endonasal transsphenoidal surgery (EETS) for pituitary macroadenoma surgery is occasionally a troublesome event by blocking the surgical field. Here we introduce an alternative technique with the new pituitary retractor and present our clinical experiences.

Methods

We designed a simple and rigid pituitary retractor with the least space occupation in the nasal cavity to be compatible in EETS. The pituitary retractor was held by external holder system to support the herniated DS stably. We retrospectively reviewed a clinical 22 cases of pituitary macroadenomas underwent EETS using the pituitary retractor.

Results

The pituitary retractor stably pushed up the herniated DS in all cases, and the surgeon proceeded the procedure with bimanual maneuver. The pituitary retractor was helpful to remove tumors around the medial cavernous sinus and behind the DS in 16 and seven cases, respectively. In four cases, the meticulous hemostasis was completed with the direct visualization by the DS elevation with this retractor. Gross total tumor resection was performed in 20/22 patients (91%). The impaired visual function and hypopituitarism were improved in 18/20 (90%) and 7/14 (50%) patients after surgery, respectively. There was no complication related with the pituitary retractor.

Conclusion

During EETS for pituitary macroadenomas, the novel pituitary retractor reported in this study is a very useful technique when the herniated DS block the surgical field and bimanual maneuver. This pituitary retractor can help to result in the excellent surgical outcomes with minimal morbidity.

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

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

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.

Endoscopic Endonasal Approach for Clipping Anterior Communicating Artery Aneurysms From Cadaver Studies and Three-Dimensional Printed Models to a Clinical Case

OBJECTIVES

Anterior communicating artery (ACoA) aneurysm is one of the most common intracranial aneurysms, and it is also the aneurysm with the highest rupture rate. With the improvement of endoscopic techniques, it is possible to use an endoscopic endonasal approach (EEA) to clip ACoA aneurysms. For further analysis of the EEA for clipping ACoA aneurysms, we used cadaver heads and three-dimensional (3D)-printed models to finish the anatomical study, and we finally selected 1 clinical case to complete the clipping through the EEA.

MATERIALS AND METHODS

We first collected 3 cadaver heads to simulate the EEA. Then, the imaging data of 29 real cases of ACoA aneurysm were collected, and the model of an aneurysm was prepared by 3D printing technology; then, the EEA was used to simulate the clipping of the aneurysm model. Finally, a clinical case with 2 ACoA aneurysms was selected to adopt the EEA for clipping.

RESULTS

Both the cadaver head and 3D-printed aneurysm model could simulate aneurysm clipping with the EEA. The clinical case of the selected ACoA aneurysm can successfully complete the clipping through the EEA.

CONCLUSIONS

3D-printed models are a good method to study the anatomical characteristics of a surgical approach. For specially selected ACoA aneurysms, the EEA is relatively simple method that can be used to clip the aneurysm successfully. The EEA for clipping ACoA aneurysms is a useful complement to the current traditional craniotomy approaches and endovascular embolization.

Long-Term Quality of Life after Endoscopic Pituitary Adenoma Surgery with Nasoseptal Flap Reconstruction

INTRODUCTION

Endoscopic endonasal transsphenoidal surgery (EETS) on the pituitary gland is considered safe and efficacious. The nasoseptal flap (NSF) is sometimes used to prevent or repair postoperative cerebrospinal fluid (CSF) leaks. Few investigators have quantified long-term quality-of-life (QOL) outcomes regarding sinonasal measures after EETS, with or without involvement of the NSF. This study assesses whether the septal flap affects sinonasal QOL outcomes for patients receiving EETS for pituitary adenoma.

METHODS AND MATERIALS

This is a retrospective study of patients who underwent EETS between 2013 and 2018. A total of 62 adults completed the Sinonasal Outcome Test-22 (SNOT-22) at least one year after the surgery. Outcome measures were compared between patients who underwent EETS with and without septal flap reconstruction.

RESULTS

For the entire cohort, there were 14 patients (22.6%) who had septal flap reconstruction and 48 patients (77.4%) who did not. Patient demographics, tumor characteristics, surgical outcomes, and duration between surgery and completion of the questionnaire were similar for both groups. The mean SNOT-22 scores in the no reconstruction (NR) group and the nasoseptal flap reconstruction (NSFR) group were similar (P=0.9). In terms of SNOT-22 subdomains (rhinologic symptoms, extranasal rhinologic symptoms, ear/facial symptoms, psychological dysfunction, and sleep dysfunction), no significant differences were found when comparing the groups.

CONCLUSION

As compared with no reconstructive involvement, NSF utilization does not affect the QOL and nasal symptoms of patients undergoing EETS.

Results of Endoscopic Surgery in Patients with Pituitary Adenomas : Association of Tumor Classification Grades with Resection, Remission, and Complication Rates

Objective

The endoscopic endonasal transsphenoidal approach is a widely-used method for the surgical treatment of pituitary adenomas. We aimed to evaluate the results of endoscopic surgery by comparing preoperative classification methods and investigating their relationship with postoperative resection and remission rates and complications.

Methods

We retrospectively reviewed the medical records of 236 patients (118 males) who underwent surgery for pituitary adenomas. Preoperative Knosp classification, tumor size (TS), suprasellar extension (SSE), postoperative resection and remission rates, and complications were evaluated.

Results

The follow-up period was 3 months to 6 years. The patients’ ages ranged between 16 and 84 years. Endocrinologically, 114 patients (48.3%) had functional adenoma (FA), and 122 patients (51.7%) had non-functional adenoma (NFA). Among the FA group, 92 (80.7%) showed remission. A statistically significant difference was found between patients with and without remission in terms of the Knosp, TS, and SSE classifications (p<0.01). Knosp, TS, and SSE classification grades were found to be correlated with the resection rates (p<0.01). Meningitis was seen in seven patients (3.0%), diabetes insipidus in 16 (6.9%; permanently in two [0.9%]), and rhinorrhea in 19 (8.1%). Thirty-six patients (15.3%) developed pituitary insufficiency and received hormone replacement therapy.

Conclusion

The resection categories and remission rates of FAs were directly proportional to the adenoma sizes and Knosp grades, while the degree of suprasellar growth further complicated resection and remission rates. Adenoma sizes less than 2 cm and SSEs less than 1 cm are associated with favorable remission and resection rates.

The manufacturing procedure of 3D printed models for endoscopic endonasal transsphenoidal pituitary surgery

BACKGROUND

Endoscopic endonasal transsphenoidal pituitary surgery is usually difficult and risky. With limited sources of cadaveric skulls, traditional methods of using virtual images to study the surgery are difficult for neurosurgeons and students because the surgery requires spatial imagination and good understanding of the patient's conditions as well as practical experience. The three-dimensional (3D) printing technique has played an important role in clinical medicine due to its advantages of low cost, high-efficiency and customization.

OBJECTIVE

CT images are used as the source data of 3D printing. The data obtained directly from the CT machine has limited accuracy, which cannot be printed without processing. Some commercial platforms can help build an accurate model but the cost and customization are not satisfactory. In this situation, a tactile, precise and low-cost 3D model is highly desirable.

METHODS

Five kinds of computer software are used in the manufacturing of medical 3D models and the processing procedure is easy to understand and operate.

RESULTS

This study proposes a practical and cost-effective method to obtain the corrected digital model and produce the 3D printed skull with complete structures of nasal cavity, sellar region and different levels of pituitary tumors. The model is used for the endoscopic endonasal transsphenoidal pituitary surgery preparation.

CONCLUSION

The 3D printed medical model can directly help neurosurgeons and medical students to practice their surgery skills on both general and special cases with customized structures and different levels of tumors.

A Meta-Analysis of Endoscopic vs. Microscopic Transsphenoidal Surgery for Non-functioning and Functioning Pituitary Adenomas: Comparisons of Efficacy and Safety

Background: Although microscopic (MTSS) and endoscopic transsphenoidal surgery (ETSS) are both effective approaches for treating non-functioning pituitary adenomas (NFPA) and functioning pituitary adenomas (FPA), the consensus remains unidentified on whether there are differences in the risk of postoperative complications between the two surgical approaches.

Method: A meta-analysis of the study of MTSS vs. ETSS for NFPA and FPA was conducted by searching the electronic databases of PubMed, Cochrane Library, and EMBASE, from the date of establishment of electronic databases to September 2020 based on the PRISMA guidelines.

Results: In this study, a total of 16 studies were selected, hailing from Belgium, the USA, India, Finland, France, Korea, Spain, China, and Canada. We enrolled 1003 patients in the ETSS and 992 patients in the MTSS group. In patients with NFPA, the ETSS group was related to a higher incidence of post-operative gross-total resection (GTR). (OR = 1.655, 95% CI 1.131–2.421, P = 0.010). In participants with FPA, the results illustrated that the ETSS group had higher rates of visual improvement (OR = 2.461, 95% CI 1.109–5.459) and gross-total resection (OR = 2.033, 95% CI 1.335–3.096), as well as lower meningitis rates (OR = 0.195, 95% CI 0.041–1.923). In participants with acromegaly, no significant difference was shown in the postoperative complications.

Conclusion: Based on current evidence, participants with NFPA treated by endoscopy were related to higher rates of GTR; patients with FPA treated by ETSS were related to higher rates of visual improvement and GTR, as well as a lower rates of meningitis.

Mononostril endoscopic endonasal approach for pituitary surgery

BACKGROUND

Most surgical teams currently consider that endoscopy has become the "gold standard" technique for the transsphenoidal approach to pituitary surgery. Pituitary adenomas are commonly benign tumours and should benefit from the least invasive approach.

METHOD

In Foch Hospital, from 2006 to 2020, 2835 patients with pituitary adenomas were treated with a mononostril endoscopic endonasal approach. Here we describe the fine details of the nasal, sphenoidal and sellar steps of this technique.

CONCLUSION

Complete preservation of the nasal corridor, luxation of the nasal septum and tailored sellar bone resection are essential for safe resection of pituitary adenomas.

Cone Beam Computed Tomography Analysis of Sphenoid Sinus Pneumatization and Relationship with Neurovascular Structures

Background

The sphenoid sinus is considered as the most variable pneumatized structure of the skull.

Purpose

The aim of the present study was to determine the prevalence of the Onodi cell as well as to evaluate the relationship between the sphenoid sinus type of pneumatization and the presence of surrounding neurovascular protrusion using cone beam computed tomography (CBCT).

Methods

The CBCT images of 500 patients/996 sides [203 males (40.6%) and 297 females (59.4%)] were analyzed in this study. The type of sphenoid sinus pneumatization, prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusion and dehiscence, and also the frequency of Onodi cell were assessed.

Results

The percentages of the conchal, presellar, sellar, postsellar (a), and postsellar (b) types of pneumatization were 1%, 11.5%, 35.5%, 38.9%, and 13.1%, respectively. The more the sphenoid sinuses pneumatized, the greater the frequency of ON and ICA protrusion and dehiscence of their wall to the sinus. The prevalence of Onodi cell was 38.8%. A significant correlation was found between ON dehiscence and the presence of Onodi cells.

Conclusion

The present study demonstrated a significant relationship between the sinus type and frequency of neurovascular protrusions. Therefore, the sphenoid sinus extent of pneumatization might be useful in predicting the risk of iatrogenic damage to the surrounding structures.

Practice patterns in the management of recurrent and residual non-functioning pituitary adenomas: Results from a Canada-wide survey

Background

There is no consensus regarding the management and postoperative follow-up of non-functioning pituitary adenomas (NFAs) in the setting of recurrent or residual disease. Subsequent treatment options include continued follow-up, re-resection or radiotherapy. To address this gap and better understand current practice patterns, we surveyed neurosurgeons and radiation oncologists in Canada.

Methods

Neurosurgeons and radiation oncologists (ROs) across Canada were invited to complete a standardized online questionnaire. Summary statistics were computed, and Fisher's Exact tests were performed to assess significance. Qualitative analyses were performed through open and axial coding.

Results

Thirty-three participants completed the questionnaires, with neurosurgeons representing a majority of respondents (n = 20 vs n = 13). When treating giant (>3 cm) tumors, 90.9% of neurosurgeons in practice for less than 10 years reported using an endoscopic approach, as compared to only 66.7% of neurosurgeons in practice for 10 years of more. Additionally, neurosurgeons who were newer to practice had a greater tendency to advocate for stereotactic radiosurgery (SRS) or re-resection (54.5% and 36.4%, respectively), as compared to older surgeons who showed a higher propensity (22.2%) to advocate for observation. The presence of cavernous sinus extension appeared to encourage ROs to offer radiotherapy sooner (61.4%), as compared to 40% of neurosurgeons.

Conclusions

Our results identified both variations and commonalities in practice amongst Canadian neurosurgeons. Approaches deviated in the setting of residual tumor based on years of practice. This work provides a critical foundation for future studies aiming to define evidence-based best practices in the management of NFAs.

•

No consensus in treatment of residual/recurrent non-functioning pituitary adenomas

•

Younger physicians prefer radiotherapy compared to senior physicians.

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Skull base neurosurgeons advocate more aggressively for re-resection.

•

There is a need for standardization of treatment guidelines.

A case series and review of the mononostril endoscopic transnasal transsphenoidal approach: Safe and effective in a low resource setting

BACKGROUND

A transnasal transsphenoidal (TNTS) approach can be performed through a binostril or mononostril technique. The binostril technique is generally preferred, however the mononostril may be an underutilized approach with significant benefits.

METHODS

All (n = 521) pituitary adenoma transsphenoidal surgeries performed from March 2008 until July 2017 at a university hospital in Indonesia were isolated. The majority (n = 512) were performed through a mononostril approach with no nasal speculum by a single experienced neurosurgeon. A PubMed literature review researching the differences in indications, techniques, and outcomes for both approaches supplements the case series. The mononostril surgical technique is described in detail.

RESULTS

The average mononostril operating time was 105 min. The most prevalent surgical complications were CSF leak (4.1 %), diabetes insipidus (3.7 %) and cacosmia (2.1 %). Visual field deficits noted in 85 %, 89 % improved. Length of stay was less than 2 days for 90 %, with 13 ICU admissions (average one day). Recurrence rate was 8.2 % at follow up (1-10 years).

CONCLUSIONS

Based on a literature review, binostril TNTS surgeries have longer operative time and a higher risk of epistaxis. According to our experience, post-operative patient comfort and satisfaction are higher with the monostril approach. Furthermore, this technique is easier to teach, ENT assistance unnecessary, and thus especially advantageous in low resource settings. Our CSF leak and tumor recurrence rates were lower than reported binostril rates in the literature. The mononostril technique is both safe and effective and should be strongly considered for an appropriately pre-selected subset of pituitary adenomas.

Analysis of Related Factors of Tumor Recurrence or Progression After Transnasal Sphenoidal Surgical Treatment of Large and Giant Pituitary Adenomas and Establish a Nomogram to Predict Tumor Prognosis

BACKGROUND

Pituitary adenoma (PA) is a benign neuroendocrine tumor caused by adenohypophysial cells, and accounts for 10%-20% of all primary intracranial tumors. The surgical outcomes and prognosis of giant pituitary adenomas measuring ≥3 cm in diameter differ significantly due to the influence of multiple factors such as tumor morphology, invasion site, pathological characteristics and so on. The aim of this study was to explore the risk factors related to the recurrence or progression of giant and large PAs after transnasal sphenoidal surgery, and develop a predictive model for tumor prognosis.

METHODS

The clinical and follow-up data of 172 patients with large or giant PA who underwent sphenoidal surgery at the Second Affiliated Hospital of Zhejiang University School of Medicine from January 2011 to December 2017 were retrospectively analyzed. The basic clinical information (age, gender, past medical history etc.), imaging features (tumor size, invasion characteristics, extent of resection etc.), and histopathological characteristics (pathological results, Ki-67, P53 etc.) were retrieved. SPSS 21.0 software was used for statistical analysis, and the R software was used to establish the predictive nomogram.

RESULTS

Seventy out of the 172 examined cases (40.7%) had tumor recurrence or progression. The overall progress free survival (PFS) rates of the patients at 1, 3 and 5 years after surgery were 90.70%, 79.65% and 59.30% respectively. Log-rank test indicated that BMI (P < 0.001), Knosp classification (P < 0.001), extent of resection (P < 0.001), Ki-67 (P < 0.001), sphenoidal sinus invasion (P = 0.001), Hardy classification (P = 0.003) and smoking history (P = 0.018) were significantly associated with post-surgery recurrence or progression. Cox regression analysis further indicated that smoking history, BMI ≥25 kg/m², Knosp classification grade 4, partial resection and ≥3% Ki-67 positive rate were independent risk factors of tumor recurrence or progression (P < 0.05). In addition, the nomogram and ROC curve based on the above results indicated significant clinical value.

CONCLUSION

The postoperative recurrence or progression of large and giant PAs is related to multiple factors and a prognostic nomogram based on BMI (≥25 kg/m²), Knosp classification (grade 4), extent of resection (partial resection) and Ki-67 (≥3%) can predict the recurrence or progression of large and giant PAs after transnasal sphenoidal surgery.