Endoscopic Endonasal Transsphenoidal Surgery: History and Evolution

Morphometric Analysis of the Sella Turcica on Cone-Beam Computed Tomography Images

INTRODUCTION

Sella turcica is an important anatomic formation that contains the pituitary gland and is in a close neighborhood with many vital structures. It is important to know the morphometry of the sella turcica, as it is a transition point during surgical interventions such as the endoscopic endonasal transsphenoidal approach to the region. The findings obtained are thought to be useful in the examination of sella turcica and surrounding structures and will contribute to the literature by knowing the morphometry of the region for the surgical method.

METHOD

In this study, cone-beam computed tomography images of 400 individuals, 200 females and 200 males, aged between 18 and 65 years, who did not have craniofacial pathology, who applied to Gaziantep University, Faculty of Dentistry between 2015 and 2020 for any reason, were evaluated retrospectively. In the sagittal section, 8 parameters were examined, 6 of which were transverse.

RESULTS

The length () of the sella turcica in the sagittal plane is 10.19±1.77 mm, the diameter of the sella turcica is 11.6±1.69 mm, the anterior height of the sella turcica is 7.88±1.56 mm, the median height of the sella turcica 8.18±1.42 mm, posterior height of sella turcica 6.98±1.31 mm, width of sella turcica 11.10±1.6 mm. The distance between anterior clinoid processes in the transverse plane was 24.93±2.57 mm, and the distance between posterior clinoid processes was 14.92±2.46 mm.

CONCLUSION

It was determined that there was an increase in many parameters with age, and length of the sella turcica and anterior clinoid processes were statistically significantly higher in males.

Endoscopic Endonasal Transsphenoidal Resection of Pituitary Adenomas in Patients Presenting With Monocular Blindness

BACKGROUND AND OBJECTIVES

Suprasellar tumors, particularly pituitary adenomas (PAs), commonly present with visual decline, and the endoscopic endonasal transsphenoidal approach (EETA) is the primary management for optic apparatus decompression. Patients presenting with complete preoperative monocular blindness comprise a high-risk subgroup, given concern for complete blindness. This retrospective cohort study evaluates outcomes after EETA for patients with PA presenting with monocular blindness.

METHODS

Retrospective analysis of all EETA cases at our institution from June 2012 to August 2023 was performed. Inclusion criteria included adults with confirmed PA and complete monocular blindness, defined as no light perception, and a relative afferent pupillary defect secondary to tumor mass effect.

RESULTS

Our cohort includes 15 patients (9 males, 6 females), comprising 2.4% of the overall PA cohort screened. The mean tumor diameter was 3.8 cm, with 6 being giant PAs (>4 cm). The mean duration of preoperative monocular blindness was 568 days. Additional symptoms included contralateral visual field defects (n = 11) and headaches (n = 10). Two patients presented with subacute PA apoplexy. Gross total resection was achieved in 46% of patients, reflecting tumor size and invasiveness. Postoperatively, 2 patients experienced improvement in their effectively blind eye and 2 had improved visual fields of the contralateral eye. Those with improvements were operated within 10 days of presentation, and no patients experienced worsened vision.

CONCLUSION

This is the first series of EETA outcomes in patients with higher-risk PA with monocular blindness on presentation. In these extensive lesions, vision remained stable for most without further decline and improvement from monocular blindness was observed in a small subset of patients with no light perception and relative afferent pupillary defect. Timing from vision loss to surgical intervention seemed to be associated with improvement. From a surgical perspective, caution is warranted to protect remaining vision and we conclude that EETA is safe in the management of these patients.

Extended endoscopic endonasal approach to the chiasmatic cistern: An anatomical study of the arachnoid

This paper studied the arachnoid of the chiasmatic cistern (CC) and the methods for increasing the exposure of the CC from an endoscopic perspective. Eight anatomical specimens with vascular injection were used for endoscopic endonasal dissection. The anatomical characteristics of the CC were studied and documented, and anatomical measurements were collected. The CC is an unpaired five-walled arachnoid cistern located between the optic nerve, optic chiasm, and the diaphragma sellae. The average exposed area of the CC before the anterior intercavernous sinus (AICS) was transected was 66.67 ± 33.76 mm2 . After the AICS was transected and the pituitary gland (PG) was mobilized, the average exposed area of the CC was 95.90 ± 45.48 mm2 . The CC has five walls and a complex neurovascular structure. It is located in a critical anatomical position. The transection of the AICS and mobilization of the PG or the selective sacrifice of the descending branch of the superior hypophyseal artery can improve the operative field.

Endoscopic endonasal transsphenoidal surgery for unusual sellar lesions: eight cases and review of the literature

Background

Preoperative imaging for some unusual lesions in the sellar region can pose challenges in establishing a definitive diagnosis, impacting treatment strategies.

Methods

This study is a retrospective analysis of eight cases involving unusual sellar region lesions, all treated with endoscopic endonasal transsphenoidal surgery (EETS). We present the clinical, endocrine, and radiological characteristics, along with the outcomes of these cases.

Results

Among the eight cases, the lesions were identified as follows: Solitary fibrous tumor (SFT) in one case, Lymphocytic hypophysitis (LYH) in one case, Cavernous sinus hemangiomas (CSH) in one case, Ossifying fibroma (OF) in two cases; Sphenoid sinus mucocele (SSM) in one case, Pituitary abscess (PA) in two cases. All patients underwent successful EETS, and their diagnoses were confirmed through pathological examination. Postoperatively, all patients had uneventful recoveries without occurrences of diabetes insipidus or visual impairment.

Conclusion

Our study retrospectively analyzed eight unusual lesions of the sellar region. Some lesions exhibit specific imaging characteristics and clinical details that can aid in preoperative diagnosis and inform treatment strategies for these unusual sellar diseases.

Neurosurgery for the rhinologist

PURPOSE OF REVIEW

The purpose of this review is to provide a comprehensive anatomical appraisal of the neurosurgical anatomy exposed through the endonasal and paranasal sinuses routes, focusing on the most common expanded endonasal approaches (EEAs) as well as recent advances in this surgical field.

RECENT FINDINGS

The EEAs are redefining the management of skull base pathology. Neurovascular structures previously considered a limitation, can be now approached through these surgical corridors. Advances in this field include the development of new surgical techniques and routes that allow better visualization and access to pathologies located in the ventral skull base. Understanding the surgical anatomy related to EEAs is essential not only for neurosurgeons but also for rhinologists.

SUMMARY

Knowledge of the surgical anatomy of the most common EEAs that utilize paranasal sinuses as a surgical corridor enables more effective management of complex skull base pathologies. Comprehensive anatomical knowledge of these corridors and the surrounding neurovascular structures is crucial to maximize benefits of EEAs and improve outcomes.

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.

Application of binasal speculum in endoscopic endonasal surgery for lesions in sellar region

Objective

This study aims to access the efficacy of the binasal speculum in endoscopic endonasal surgery by evaluating clinical outcomes and examining its utility through process-based performance measures in both surgeons and assistants.

Methods

A total of 59 patients with lesions in sellar region who underwent endoscopic endonasal surgery with the binasal speculum between September 2020 and March 2023 were included in this study. We assessed the extent of resection and documented postoperative nasal condition. Both surgeons and assistants completed post-use surveys to exam the utility of the binasal speculum and provide an overall grading.

Results

Gross total resection (GTR) was successfully achieved in 94.9% (56/59) of patients, with subtotal resection (STR) observed in 5.1% (4/59) of patients. Intraoperative cerebrospinal fluid (CSF) leakage occurred in 23.7% (14/59) of cases, and nasoseptal flap (NSF) reconstruction was required in 55.9% (33/59) of cases. The nasal airway patency rapidly recovered within 14 days in a significant majority of patients (94.9%, 56/59). Moreover, olfactory function was regained within three months postoperatively by 91.5% (54/59) of patients. The overall post-use survey mean score was 26.4. Specifically, surgeons had a mean score of 26.5, while assistants had a slightly lower mean score of 26.2. The mean overall grading for the binasal speculum was 3. Both surgeons and assistants provided a mean overall grading of 3.

Conclusion

The binasal speculum provides nasal mucosa protection and reduces the risk of an endoscopic lens clouded by mucosa or blood. It plays a crucial role in accurate guidance and facilitates the swift delivery of surgical instruments, particularly in left-blinded nasal cavities. The binasal speculum reduces the learning curve, especially for endoscopic surgeons with limited experience, while enhancing collaboration and coordination between surgeons and assistants during surgery. Both surgeons and assistants rated the overall utility of the binasal speculum as "excellent."

The Role of Augmented Reality Neuronavigation in Transsphenoidal Surgery: A Systematic Review

In the field of minimally invasive neurosurgery, microscopic transsphenoidal surgery (MTS) and endoscopic transsphenoidal surgery (ETS) have been widely accepted as a safe approach for pituitary lesions and, more recently, their indications have been extended to lesions at various skull base regions. It is mandatory during transsphenoidal surgery (TS) to identify key anatomical landmarks in the sphenoid sinus and distinguish them from the lesion. Over the years, many intraoperative tools have been introduced to improve the neuronavigation systems aiming to achieve safer and more accurate neurosurgical interventions. However, traditional neuronavigation systems may lose the accuracy of real-time location due to the discrepancy between the actual surgical field and the preoperative 2D images. To deal with this, augmented reality (AR)-a new sophisticated 3D technology that superimposes computer-generated virtual objects onto the user's view of the real world-has been considered a promising tool. Particularly, in the field of TS, AR can minimize the anatomic challenges of traditional endoscopic or microscopic surgery, aiding in surgical training, preoperative planning and intra-operative orientation. The aim of this systematic review is to analyze the potential future role of augmented reality, both in endoscopic and microscopic transsphenoidal surgeries.

Transorbital and supraorbital uniportal multicorridor approach to the orbit, anterior, middle and posterior cranial fossa: Anatomic study

Introduction

The transorbital route has been proposed for addressing orbital and paramedian skull base lesions. It can be complemented by further marginotomies, as per "extended-transorbital approach" and combined with others ventro-basal approaches featuring the concept of "multiportal surgery". Nevertheless, it cannot address some anatomical regions like the clinoid, carotid bifurcation and the Sylvian fissure. Therefore, we propose a combined transorbital and a supraorbital approach, attainable by a single infra-brow incision, and we called it "Uniportal multicorridor" approach.

Research question

The aim of our study is to verify its feasibility and deep anatomical targets through a cadaveric study.

Materials and methods

Anatomic dissections were performed at the Laboratory of ICLO Teaching and Research Center (Verona, Italy) on four formalin-fixed cadaveric heads injected with colored neoprene latex (8 sides). A stepwise dissection of the supraorbital and transorbital approaches (with an infra-brow skin incision) to the anterior tentorial incisura, clinoid area, lateral wall of the cavernous sinus, middle temporal fossa, posterior fossa, and Sylvian fissure is described.

Results

We analyzed the anatomic areas reached by the transorbital corridor dividing them as follow: lateral wall of the cavernous sinus, middle temporal fossa, posterior fossa, and Sylvian fissure; while the anatomic areas addressed by the supraorbital craniotomy were the clinoid area and the anterior tentorial incisura.

Conclusions

The described uniportal multi-corridor approach combines a transorbital corridor and a supraorbital craniotomy, providing a unique intra and extradural control over the anterior, middle, and posterior fossa, tentorial incisura and the Sylvian fissure, via an infra-brow skin incision.

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.

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

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

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.

Adamantinomatous craniopharyngioma: evolution in the management

BACKGROUND

In spite of the continuous progresses in pediatric neurosurgery, adamantinomatous craniopharyngioma (AC) remains a challenging tumor due to its proximity to optic pathways, pituitary gland, hypothalamus, and Willis' circle, which can result in significant endocrine, cognitive, and neurological morbidity after treatment with subsequent impact on the patient's quality of life (QoL). The relevance that QoL has today explains the changes in the management of AC observed over the time. The goal of the present article is to provide a historical background, to show the milestones in the changes of the AC treatment, and to analyze the current main options to manage such a challenging tumor.

MATERIAL AND METHODS

The pertinent literature has been reviewed. Moreover, a comparison between the past and recent personal series is reported.

RESULTS

Three main eras have been identified. The first (named Cushing era) was characterized by the need to realize a harmless surgery and to define the best way to approach AC; the second (microscope era) was characterized by a tremendous technical and technological development, with remarkable results in term of safe tumor resection and control but relatively poor QoL outcomes; and the third one (current period) is characterized by an increasing integration between surgery and adjuvant treatments, with relatively minor tumor control but significant improvement of QoL (comparable overall survival). The authors' experience reflects these changes. Two groups of children were compared: 52 cases (mean follow-up: 17.5 years) belong to the historical series (group 1, 1985-2003, aggressive surgical management) and 41 (mean follow-up: 8.5 years) to the current one (Group 2, 2004-2021, integrated management). No significant differences between the two groups were detected about recurrence rate, surgical mortality, and overall survival. However, Group 2 showed significant lower rates of postoperative panhypopituitarism, obesity, and visual deterioration.

CONCLUSIONS

Radical surgery allows for a good AC control with a low rate of recurrence but high risk of permanent morbidity. Despite the greater number of recurrences and surgeries, the more conservative policy, based on a combination of treatments, seems to provide the same tumor control with a better QoL. The advances in trans-nasal and trans-ventricular endoscopy, in proton therapy and in the management of the AC cyst are the main factors that allowed such an improvement.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Endoscopic Endonasal Approach to the Sellar and Parasellar Regions

Introduction  Surgery of the sellar and parasellar regions can be challenging due to the complexity of neurovascular relationships. The main goal of this study is to develop an educational resource to help trainees understand the pertinent anatomy and procedural steps of the endoscopic endonasal approaches (EEAs) to the sellar and parasellar regions. Methods  Ten formalin-fixed latex-injected specimens were dissected. Endoscopic endonasal transsphenoidal transsellar, transtuberculum-transplanum, and transcavernous approaches were performed by a neurosurgery trainee, under supervision from the senior authors and a PhD in anatomy with advanced neuroanatomy experience. Dissections were supplemented with representative case applications. Results  Endoscopic endonasal transsphenoidal approaches afford excellent direct access to sellar and parasellar regions. After a wide sphenoidotomy, a limited sellar osteotomy opens the space to sellar region and medial portion of the cavernous sinus. To reach the suprasellar space (infrachiasmatic and suprachiasmatic corridors), a transplanum-prechiasmatic sulcus-transtuberculum adjunct is needed. The transcavernous approach gains access to the contents of the cavernous sinus and both medial (posterior clinoid and interpeduncular cistern) and lateral structures of the retrosellar region. Conclusion  The anatomical understanding and technical skills required to confidently remove skull base lesions with EEAs are traditionally gained after years of specialized training. We comprehensively describe EEAs to sellar and parasellar regions for trainees to build knowledge and improve familiarity with these approaches and facilitate comprehension and learning in both the surgical anatomy laboratory and the operating room.

Update on the Diagnosis and Management of Meningiomas

This series of five articles (one original article and four reviews) focuses on the most recent and interesting research studies on the biomolecular and radiological diagnosis and the surgical and medical management of meningiomas [...].

History, Current Techniques, and Future Prospects of Surgery to the Sellar and Parasellar Region

The sellar and parasellar region can be affected by diverse pathologies. The deep-seated location and surrounding critical neurovascular structures make treatment challenging; there is no singular, optimal approach for management. The history and development of transcranial and transsphenoidal approaches by pioneers in skull base surgery were largely aimed at treating pituitary adenomas, which are the most common lesions of the sella. This review explores the history of sellar surgery, the most commonly used approaches today, and future considerations for surgery of the sellar/parasellar region.

Current Role of Endoscopic Endonasal Approach for Craniopharyngiomas: A 10-Year Systematic Review and Meta-Analysis Comparison with the Open Transcranial Approach

In recent years, the endoscopic endonasal approach (EEA) for craniopharyngiomas has proven to be a safe option for extensive tumor resection, with minimal or no manipulation of the optic nerves and excellent visualization of the superior hypophyseal branches when compared to the Transcranial Approach (TCA). However, there is an ongoing debate regarding the criteria for selecting different approaches. To explore the current results of EEA and discuss its role in the management of craniopharyngiomas, we performed MEDLINE, Embase, and LILACS searches from 2012 to 2022. Baseline characteristics, the extent of resection, and clinical outcomes were evaluated. Statistical analysis was performed through an X² and Fisher exact test, and a comparison between quantitative variables through a Kruskal-Wallis and verified with post hoc Bonferroni. The tumor volume was similar in both groups (EEA 11.92 cm³, -TCA 13.23 cm³). The mean follow-up in months was 39.9 for EEA and 43.94 for TCA, p = 0.76). The EEA group presented a higher visual improvement rate (41.96% vs. 25% for TCA, p < 0.0001, OR 7.7). Permanent DI was less frequent with EEA (29.20% vs. 67.40% for TCA, p < 0.0001, OR 0.2). CSF Leaks occurred more frequently with EEA (9.94% vs. 0.70% for TCA, p < 0.0001, OR 15.8). Recurrence rates were lower in the EEA group (EEA 15.50% vs. for TCA 21.20%, p = 0.04, OR 0.7). Our results demonstrate that, in selected cases, EEA for resection of craniopharyngiomas is associated with better results regarding visual preservation and extent of tumor resection. Postoperative CSF leak rates associated with EEA have improved compared to the historical series. The decision-making process should consider each person's characteristics; however, it is noticeable that recent data regarding EEA justify its widespread application as a first-line approach in centers of excellence for skull base surgery.

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

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Efficacy of a Novel Augmented Reality Navigation System Using 3D Computer Graphic Modeling in Endoscopic Transsphenoidal Surgery for Sellar and Parasellar Tumors

In endoscopic transsphenoidal skull base surgery, knowledge of tumor location on imaging and the anatomic structures is required simultaneously. However, it is often difficult to accurately reconstruct the endoscopic vision of the surgical field from the pre-surgical radiographic images because the lesion remarkably displaces the geography of normal anatomic structures. We created a precise three-dimensional computer graphic model from preoperative radiographic data that was then superimposed on a visual image of the actual surgical field and displayed on a video monitor during endoscopic transsphenoidal surgery. We evaluated the efficacy of this augmented reality (AR) navigation system in 15 consecutive patients with sellar and parasellar tumors. The average score overall was 4.7 [95% confidence interval: 4.58-4.82], which indicates that the AR navigation system was as useful as or more useful than conventional navigation in certain patients. In two patients, AR navigation was assessed as less useful than conventional navigation because perception of the depth of the lesion was more difficult. The developed system was more useful than conventional navigation for facilitating an immediate three-dimensional understanding of the lesion and surrounding structures.

Impact of Facility Volume on Patient Safety Indicator Events After Transsphenoidal Pituitary Surgery

OBJECTIVES

To investigate the impact of facility volume on Patient Safety Indicator (PSI) events following transsphenoidal pituitary surgery (TSPS).

STUDY DESIGN

Retrospective database review.

SETTING

National Inpatient Sample database (2003-2011).

METHODS

The National Inpatient Sample was queried for TSPS cases from 2003 to 2011. Facility volume was defined by tertile of average annual number of TSPS procedures performed. PSIs, based on in-hospital complications identified by the Agency of Healthcare Research and Quality, and poor outcomes, such as mortality and tracheostomy, were analyzed.

RESULTS

An overall 16,039 cases were included: 804 had ≥1 PSI and 15,235 had none. A greater proportion of male to female (5.8% vs 4.3%) and Black to White (7.0% vs 4.5%) patients experienced PSIs. There was an increased likelihood of poor outcome (odds ratio [OR], 3.1 [95% CI, 2.5-3.7]; P < .001) and mortality (OR, 30.1 [95% CI, 18.5-48.8]; P < .001) with a PSI. The incidence rates of PSIs at low-, intermediate-, and high-volume facilities were 5.7%, 5.1%, and 4.2%, respectively. Odds of poor outcome with PSIs were greater at low-volume facilities (OR, 3.3 [95% CI, 2.4-4.4]; P < .001) vs intermediate (OR, 3.1 [95% CI, 2.1-4.2]; P < .001) and high (OR, 2.5 [95% CI, 1.7-3.8]; P < .001). Odds of mortality with PSIs were greater at high-volume facilities (OR, 43.0 [95% CI, 14.3-129.4]; P < .001) vs intermediate (OR, 40.0 [95% CI, 18.5-86.4]; P < .001) and low (OR, 17.3 [95% CI, 8.0-37.7]; P < .001).

CONCLUSION

PSIs were associated with a higher likelihood of poor outcome and mortality following TSPS. Patients who experienced PSIs had a lower risk of poor outcome but increased mortality at higher-volume facilities.

Endoscopic endonasal surgical anatomy of the optic canal: key anatomical relationships between the optic nerve and ophthalmic artery

PURPOSE

A detailed understanding of the neurovascular relationships between the optic nerve (ON) and the ophthalmic artery (OA) in the optic canal (OC) is paramount for safe surgery. We focused on the neurovascular anatomy of this area from both an endoscopic endonasal and transcranial trajectories to compare the surgical exposures and perspectives offered by these different views and provide recommendations to increase the intraoperative safety.

METHODS

Twenty sides of ten formalin-fixed, latex-injected head specimens were utilized. The surgical anatomy and anatomical relationships of the OA in relationship to the ON along their intracranial and intracanalicular segments was studied from endoscopic endonasal and transcranial perspectives.

RESULTS

Three types of OA-ON relationships at the origin of the OA were identified: inferomedial (type 1, 35%), inferior (type 2, 55%), and inferolateral (type 3, 10%). The endoscopic endonasal trajectory offers an inferomedial perspective of the ON-OA neurovascular complex, in which the OA, especially when located inferomedially, is first encountered. When comparing with the transcranial view, all OA were covered by the nerve, type 1 was located below the medial third, type 2 below the middle third, and type 3 below the lateral third of the OC. The mean extension of the intracanalicular portion of both OA and ON was 8.9 mm, while the intracranial portion of the OA and ON were 9.3 mm and 12.4 mm, respectively. The OA, endoscopically, is located within the inferior half of the OC, and occupies 39%, 43%, and 42% of the OC height at its origin, mid, and end points, respectively. The mean distance between the superior margin of the OC at its origin and superior margin of the OA is 1.4 mm.

CONCLUSIONS

Detailed anatomical understanding of the OC, and the ON and OA at their intracranial and intracanalicular segments is paramount to safe surgery. When opening the OC dura endoscopically, our results suggest that a medial incision along the superior third of the OC with a proximal to distal direction is recommended to avoid injury of the OA.

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.

Does High-Definition 3-Dimensional Imaging Improve Orientation During Endoscopic Transsphenoidal Surgery? A Prospective Trial

BACKGROUND

Endoscopy has evolved as the standard visualization tool for endonasal transsphenoidal resection of sellar lesions. The most widely used 2-dimensional (2D) endoscopes harbor the problem of limited depth perception. Therefore, 3-dimensional (3D) endoscopes have been developed to enable depth perception through a stereoscopic view.

OBJECTIVE

To evaluate the impact of high-definition (HD) 2D vs 3D HD endoscopes on spatial orientation within the sphenoid sinus.

METHODS

In this prospective single-center study, 21 patients have been investigated (2021-2022). Eleven standardized anatomic landmarks, which were preoperatively defined on neuronavigation imaging, were intraoperatively targeted with a navigation probe using either 2D HD or 3D HD endoscopes for visualization.

RESULTS

Overall, 3D HD endoscopes provided a statistically significant higher accuracy of identification of sphenoid sinus landmarks (median deviation: 5.2 mm vs 4.2 mm, P < .001). In detail: tuberculum sellae (3.0 mm vs 4.3 mm, P = .047), most anterior point of sella (3.3 mm vs 4.8 mm, P = .049), and clivus indentation (3.8 mm vs 5.3 mm, P = .035). Anatomic variations such as a complex sphenoid sinus configuration had no influence on identifying sphenoid sinus landmarks.

CONCLUSION

According to our data, stereoscopic 3D HD endoscopy enhances intraoperative orientation by improved depth perception within the sphenoid sinus. This may add to the safety of endoscopic skull base procedures, especially in extended approaches and cases with distorted anatomy.

Retrospective Review of Surgical Site Infections after Endoscopic Endonasal Sellar and Parasellar Surgery: Multicenter Quality Data from the North American Skull Base Society

Introduction  Transnasal access to the anterior skull base provides a minimally invasive approach for sellar and parasellar masses compared with its open counterparts. The unique microbiome of the sinonasal mucosa provides distinct challenges not encountered with other cranial approaches. The use of antibiotics in these cases has not been standardized, and data remain scarce regarding infectious outcomes. Methods  We conducted a multicenter retrospective analysis of shared quality data points for the endoscopic endonasal approach (EEA) for pituitary adenomas, along with other sellar and parasellar region masses that were included by participating institutions. Patient and operative characteristics, perioperative and postoperative antibiotic regimens and their durations, intraoperative and postoperative cerebrospinal fluid leak, and onset of postoperative meningitis and sinusitis were compared. Results  Fifteen institutions participated and provided 6 consecutive months' worth of case data. Five hundred ninety-three cases were included in the study, of which 564 were pituitary adenomectomies. The incidences of postoperative meningitis and sinusitis were low (0.67 and 2.87% for all pathologies, respectively; 0.35% meningitis for pituitary adenomas) and did not correlate with any specific antibiotic regimen. Immunocompromised status posed an increased odds of meningitis in pituitary adenomectomies (28.6, 95% confidence interval [1.72-474.4]). Conclusions  The results show no clear benefit to postoperative antimicrobial use in EEA, with further larger studies needed.

Endoscopic versus Nonendoscopic Surgery for Resection of Craniopharyngiomas

OBJECTIVE

While surgery is a critical treatment option for craniopharyngiomas, the optimal surgical approach remains under debate. Herein, we studied a large cohort of craniopharyngioma patients to identify predictors of endoscopic surgery (ES) and to compare survival outcomes between patients undergoing ES versus nonendoscopic surgery (NES).

METHODS

The National Cancer Database was queried for patients receiving definitive surgical treatment in 2010-2016. Cox proportional hazards and propensity score-adjusted Kaplan-Meier analyses assessed mortality risk and overall survival, respectively. Predictors of surgical approach were evaluated via logistic regression.

RESULTS

Of 1721 patients, 508 (29.5%) underwent ES, 877 (50.9%) were female, and the average age was 41.8 ± 21.3 years. Matched ES and NES cohorts exhibited 5-year overall survival rates of 88.0% and 79.8%, respectively (P = 0.004). ES was associated with reduced mortality (Hazard Ratio = 0.634; 95% confidence interval [CI], 0.439-0.914; P = 0.015). Patients treated at academic facilities (Odds Ratio [OR] = 2.095; 95% CI, 1.529-2.904; P < 0.001) or diagnosed recently (OR = 1.132; 95% CI, 1.058-1.211; P < 0.001) were more likely to undergo ES, while those with tumor sizes >3 cm (OR = 0.604; 95% CI, 0.451-0.804; P < 0.001) or receiving adjuvant radiotherapy (OR = 0.641; 95% CI, 0.454-0.894; P = 0.010) were more likely to receive NES. Surgical inpatient stays were significantly shorter with ES compared to NES (8.0 vs. 10.5 days, P < 0.001). On linear regression, ES usage increased by 82.4% and NES usage decreased by 23.4% between 2010 and 2016 (R² = 0.575, P = 0.031).

CONCLUSIONS

ES of craniopharyngioma was associated with reduced mortality and shorter inpatient stays compared to NES. Factors including tumor size, extent of resection, facility type, and year of diagnosis may predict receiving ES. There is a trend towards increased usage of ES for surgical management of craniopharyngiomas.

The use of three-dimensional endoscope in transnasal skull base surgery: A single-center experience from China

Objective

The development of skull base surgery in the past decade has been influenced by advances in visualization techniques; recently, due to such improvements, 3D endoscopes have been widely used. Herein, we address its effect for transnasal endoscopic skull base surgery.

Methods

A total of 63 patients who under endoscopic endonasal surgery (EES) with 3-D endoscope were retrospectively reviewed, including pituitary adenomas, craniopharyngiomas, meningiomas, Rathke’s cleft cysts, and chordomas. According to different lesions, transsellar approach (24 cases), transsphenoidal–transtuberculum approach (14 cases), transclival approach (6 cases), and transpterygoid approach (19 cases) were selected.

Results

Total removal of tumors was achieved in 56 patients (88.9%) and subtotal removal in 7 cases (11.1%). Complications included diabetes insipidus in seven patients (11.1%), cerebrospinal fluid (CSF) leakage in two patients (3.2%), major vascular injury occurred in one patient (1.6%), cranial nerve injury in nine patients (14.3%), and meningitis in two patients (3.2%). There was no mortality in the series. All patients recovered and were back to normal daily life, and no tumor recurrence or delayed CSF leakage was detected during the follow-up (2–13 months, mean 7.59 months).

Conclusions

Via 3D EES, it improved depth perception and preserved important neurovascular tissue when tumors were removed, which is important for improving the operative prognosis.

Use of balloon-assisted nasal access to augment endoscopic endonasal transsphenoidal approach: illustrative case

BACKGROUND

Pituitary adenoma is a neurosurgical pathology commonly resected via endoscopic endonasal approach. Septal and nasal passage anatomy can affect the surgical corridor and may require septoplasty or other techniques for expansion.

OBSERVATIONS

The authors presented a case of pituitary macroadenoma with septal deviation with use of balloon-assisted nasal access for surgery.

LESSONS

This technique enhanced surgical width of field and instrument maneuverability via septal medialization for successful tumor resection.

Endoscopic pituitary surgery: A national database review

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Midline Skull Base Meningiomas: Transcranial and Endonasal Perspectives

Simple Summary

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. Over time, several corridors have been proposed, each one carrying its own pros and cons. During the last decades, the endoscopic endonasal route has been asserted among the classic routes for a growing number of midline and paramedian lesions. Therefore, the aim of our paper is to present a comprehensive review of the indications and techniques for the management of skull base meningiomas, emphasizing the ambivalent and complementary role of the low and high routes.

Abstract

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. The state of the art of skull base meningiomas accounts for both transcranial, or high, and endonasal, or low, routes. A comprehensive review of the pertinent literature was performed to address the surgical strategies and outcomes of skull base meningioma patients treated through a transcranial approach, an endoscopic endonasal approach (EEA), or both. Three databases (PubMed, Ovid Medline, and Ovid Embase) have been searched. The review of the literature provided 328 papers reporting the surgical, oncological, and clinical results of different approaches for the treatment of skull base meningiomas. The most suitable surgical corridors for olfactory groove, tuberculum sellae, clival and petroclival and cavernous sinus meningiomas have been analyzed. The EEA was proven to be associated with a lower extent of resection rates and better clinical outcomes compared with transcranial corridors, offering the possibility of achieving the so-called maximal safe resection.

Clinical Significance of Nasal Pathologies in Transnasal Transsphenoidal Pituitary Surgery

BACKGROUND

We evaluated the frequency of nasal pathologies and the significance of surgical access to the sellar region in patients who underwent an operation for sellar mass using the endonasal and microscopic transsphenoidal approaches.

METHODS

We retrospectively evaluated all patients who underwent surgery for pituitary macroadenoma using microscopic (n = 78) and endonasal (n = 20) transsphenoidal approaches. Patients' epicrisis, preoperative, and postoperative imaging as well as their operative notes were reviewed. Nasal pathologies and surgeries performed before or during the pituitary surgery were also documented. All endonasal surgeries were binostril and performed jointly by an ear, nose, and throat specialist and neurosurgeon. To determine the feasibility of endonasal and microscopic approaches, we developed an algorithm using the septum deviation classifications to determine the need for septoplasty.

RESULTS

The most common nasal pathology was septum deviation (n = 17; 17.3%). Of the other nasal pathologies, 6 cases (6%) were chronic sinusitis and 2 were (2.1%) middle turbinate bullosa.

CONCLUSIONS

The preoperative evaluation of patients undergoing endonasal transsphenoidal surgery by an ear, nose, and throat surgeon allows for the detection and treatment of nasal pathologies that may lead to serious perioperative and postoperative complications. Evaluating patients with septum deviation using our classification will help determine the necessity of preoperative or perioperative septum surgery, depending on the preferred pituitary surgical method.

Endoscopic endonasal surgical anatomy through the prechiasmatic sulcus: the key window to suprachiasmatic and infrachiasmatic corridors

BACKGROUND

Classically, the transtuberculum and transplanum approaches have been utilized to reach the suprachiasmatic and infrachiasmatic corridors. The aim of this study was to provide a better understanding of the key endoscopic endonasal anatomy of the suprachiasmatic and infrachiasmatic corridors provided through selective removal of the prechiasmatic sulcus (SRPS).

METHOD

A SRPS was performed in 16 sides of 8 alcohol-fixed head specimens. Twenty anatomical measurements were collected on the suprachiasmatic and infrachiasmatic corridors. The transplanum and transtuberculum approaches were also performed.

RESULTS

In the suprachiasmatic corridor, the SRPS exposed the anterior communicating artery (AComm) and the post-communicating segment of the anterior cerebral arteries in all the cases, while the pre-communicating segment of the anterior cerebral arteries, recurrent arteries of Heubner, and fronto-orbital arteries were visualized in 75% (12/16), 31% (5/16), and 69% (11/16) of cases, respectively. In the infrachiasmatic corridor, the ophthalmic segment of the internal carotid artery and superior hypophyseal arteries were always visible through the SRPS. The mean width and height of the prechiasmatic sulcus were 13.2 mm and 9.6 mm, respectively. The mean distances from the midpoint of the AComm to the anterior margin of the optic chiasm (OCh) was 5.3 mm. The mean width of the infrachiasmatic corridor was 12.3 mm at the level of the proximal margin of the ophthalmic segment of the internal carotid artery. The mean distances from the posterior superior limit of the pituitary stalk to the basilar tip and oculomotor nerve were 9.7 mm and 12.3 mm, respectively.

CONCLUSIONS

The SRPS provides access to the main neurovascular and cisternal surgical landmarks of the suprachiasmatic and infrachiasmatic corridors. This anatomical area constitutes the key part of the approach to the suprasellar area. To afford adequate surgical maneuverability, the transplanum or transtuberculum approaches are usually a necessary extension.

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.

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.

Anesthetic management during transsphenoidal pituitary surgery

PURPOSE OF REVIEW

Pituitary adenoma resections comprise a large proportion of intracranial tumor surgeries. This patient population is medically and physiologically complex and requires careful perioperative planning and management on the part of the anesthesiologist. This review will summarize anesthetic considerations for pre, intra, and postoperative management of patients undergoing transsphenoidal pituitary surgery.

RECENT FINDINGS

An endoscopic approach is favored for patients undergoing transsphenoidal pituitary surgery. Hemodynamic monitoring is important to maintain cerebral perfusion and avoid risk of bleeding; however, 'controlled' hypotension may have adverse effects. Multimodal analgesia is effective for the management of postoperative pain and may reduce the risk of postoperative complications, including respiratory depression and postoperative nausea and vomiting.

SUMMARY

Transsphenoidal pituitary surgery is a preferred approach for the surgical management of nonfunctioning pituitary macroadenomas with symptoms of mass effect and functioning adenomas that cannot be otherwise managed medically. Understanding tumor pathologies and systemic effects are essential for preoperative planning and providing safe anesthetic care during the perioperative period.

Role of Anterior Nasal Packing in Endoscopic Skull Base Surgery: Italian Survey

BACKGROUND

Nowadays, the endoscopic endonasal approach to sellar and parasellar region tumors is a common technique in neurosurgery, and surgical nuances, complications, and management strategies are shared in a multidisciplinary setting between neurosurgeons and ear, nose, and throat surgeons. Due to the heterogeneity of its variations, the role of the anterior nasal packing in endoscopic endonasal approach to the skull base surgery (EESBS) has not yet been unanimously accepted and no consensus or guidelines on its use exist.

MATERIALS AND METHODS

A survey containing 10 questions about indications, management advantages, and pitfalls of the use of anterior nasal packing in EESBS was created by using an online open-source tool (SurveyMonkey). The questionnaire was sent to 39 Italian neurosurgical departments, which routinely adopt the endoscopic endonasal approach.

RESULTS

Almost half of 39 selected centers (19; 48.7%) answered our survey. The main results can be summarized as 1) anterior nasal packing after EESBS is considered useful by 84% of participants, 2) prevention of epistaxis is the principal indication for anterior nasal packing, 3) the type of approach and skull base reconstruction influence the use of anterior nasal packing, and 4) nasal discomfort is considered the principal negative aspect of nasal packing.

CONCLUSIONS

Our study identified that anterior nasal packing is commonly adopted in certain conditions, namely when extensive nasal dissection is performed. Furthermore, the choice to adopt or not the anterior nasal packing should be tailored taking in account specific conditions, such as acromegaly and Cushing disease. It represents an important factor in reducing postoperative sinonasal complications of EESB.

Endoscopic Endonasal Transsphenoidal Approach for Third Ventriculostomy in the Management of Obstructive Hydrocephalus

ABSTRACT

Endoscopic third ventriculostomy (ETV) is a safe and effective method for the management of obstructive hydrocephalus. Traditional approach is a transfrontal trajectory through the foramen of Monro to access and open the third ventricle floor. Though endoscopic endonasal transsphenoidal approach (EETA) for pituitary and skull base tumors has become increasingly popular, no published literature has explored its utility in performing an ETV. Here, the authors reported a successful ETV for obstructive hydrocephalus through the EETA. A 57-year-old male presenting with progressive headache and gait disturbance for 3 months was diagnosed with obstructive hydrocephalus. Brain MRI revealed an obstruction of cerebrospinal fluid (CSF) flow at the cerebral aqueduct and supratentorial hydrocephalus, accompanied with dilatation and downward herniation of the third ventricle floor. Considering the displacement of the third ventricle floor and the indication for surgery, an ETV was successfully performed through the EETA. No postoperative complication was observed. Both radiological and clinical evaluation postoperatively confirmed ETV success with decreased ventricular size, increased CSF flow across the floor of the third ventricle, and improved clinical signs. EETA is a feasible approach for ETV in selected cases of obstructive hydrocephalus. This approach provides a short trajectory to directly visualize and open the Liliequist's membrane and the displaced floor of the third ventricle, while minimizes damage to normal brain tissue. Skull base repair with nasoseptal flap ensures the success rate by preventing postoperative CSF leak and infection.

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.

Early Experience of Endoscopic Endonasal Transphenoidal Surgery for Pituitary Adenoma: Preliminary Report of 56 Cases Operated in a West African Institution

BACKGROUND

Although endoscopic endonasal approach (EEA) has been popularized worldwide for pituitary adenoma surgery, in sub-Saharan Africa, neurosurgeons are still only starting their experience with it. This study was designed to assess the early results of EEA for pituitary adenoma from an under-equipped environment, namely, the Department of Neurosurgery of the Teaching Hospital of Yopougon Abidjan and Bouaké in Ivory Coast.

METHODS

The data of 56 cases of EEA for pituitary adenoma surgery performed between 2016 and March 2019 at the Teaching Hospital of Yopougon-Abidjan and Bouaké were retrospectively assessed. Pre- and postoperative neuro-ophthalmologic and hormonal status were analyzed. Moreover, the quality of tumor removal, and pre- and postoperative complications were also evaluated.

RESULTS

In this study, there were nonfunctional adenomas (20), prolactinoma (18), Cushing disease (9), and acromegaly (3). A reduced visual acuity and/or visual field defect was observed in 49 cases. The mean operation time was 225 ± 94.7 minutes. The tumor removals were complete in 57.14%, subtotal in 35.71%, and partial in 7.14%. These led to a visual improvement in 69.64%. Postoperative complications were cerebrospinal fluid leaks (19.64%), diabetes insipidus (12.50%), visual worsening (7.14%), meningitis (3.57%), and carotid injury (3.57%) that led to death.

CONCLUSIONS

This study represents the early surgical experience using EEA for treating pituitary adenoma in an under-equipped environment. Although the postoperative complication rate was relatively high, refinements of local surgeons' technique would lead to a better patient outcome.

Transorbital endoscopic approaches to the skull base: a systematic literature review and anatomical description

Transorbital endoscopic approaches are increasing in popularity as they provide corridors to reach various areas of the ventral skull base through the orbit. They can be used either alone or in combination with different approaches when dealing with the pathologies of the skull base. The objective of the current study is to evaluate the surgical anatomy of transorbital endoscopic approaches by cadaver dissections as well as providing objective clinical data on their actual employment and morbidity through a systematic review of the current literature. Four cadaveric specimens were dissected, and step-by-step dissection of each endoscopic transorbital approach was performed to identify the main anatomic landmarks and corridors. A systematic review with pooled analysis of the current literature from January 2000 to April 2020 was performed and the related studies were analyzed. Main anatomical landmarks are presented based on the anatomical study and systematic review of the literature. With emphasis on the specific transorbital approach used, indications, surgical technique, and complications are reviewed through the systematic review of 42 studies (19 in vivo and 23 anatomical dissections) including 193 patients. In conclusion, transorbital endoscopic approaches are promising and appear as feasible techniques for the surgical treatment of skull base lesions. Surgical anatomy of transorbital endoscopic approaches can be mastered through knowledge of a number of anatomical landmarks. Based on data available in the literature, transorbital endoscopic approaches represent an important complementary that should be included in the armamentarium of a skull base team.

Sellar Region Lesions and Intracranial Aneurysms in the Era of Endoscopic Endonasal Approach

In the clinical practice of neurosurgery, the endoscopic endonasal approach (EEA) has been the mainstream approach in the management of sellar region diseases. However, clinicians have come to realize that EEA procedure is associated with intraoperative hemorrhage. Due to the limited surgical field and poor proximal control under endoscope, massive hemorrhage always leads to severe complication or even perioperative death. Previously, intraoperative hemorrhage used to be attributed to endoscopic intervention of cavernous sinus or internal carotid artery, but our recent understanding of EEA indicated that preoperatively complicated intracranial aneurysms (IAs) may play a role. In this article, we retrospectively reviewed the baseline characteristics, treatment strategy, pathology, intraoperative findings, as well as radiological profiles of sellar region lesions complicated with IAs. With the focus put on the high comorbidity rate of sellar region lesions and IAs, we did further statistical analysis to sketch the outline of this coexisting circumstance and to emphasize the importance of computed tomography angiography (CTA) as routine EEA preoperative examination. Thorough patient-surgeon communication should be proceeded before the formulation of an individualized treatment strategy.

Improvement in the Quality of Early Postoperative Course After Endoscopic Transsphenoidal Pituitary Surgery: Description of Surgical Technique and Outcome

Objective: The endoscopic transsphenoidal pituitary surgery has gained popularity and has shown excellent results with a more comfortable postoperative course. However, the quality of the early postoperative course is not well-established in endoscopic transsphenoidal pituitary surgery. We hypothesized that the quality of the early postoperative course would be improved when an enhanced recovery after surgery (ERAS) protocol and minimally invasive endoscopic transsphenoidal pituitary surgery is implemented.

Methods: We implemented a perioperative management ERAS protocol for endoscopic transsphenoidal pituitary surgery by an experienced surgeon (Yuehui Ma) in our department from January 2018. From then the endoscopic transsphenoidal pituitary surgery was implemented with a minimally invasive technique, such as bony sella reconstruction and partial nasal packing. We compared the results of 78 endoscopic transsphenoidal pituitary surgery cases during the initiation of the ERAS protocol and minimally invasive technique implementation: 37 cases in the control group and 41 cases in the ERAS group. Outcomes assessed included the effectiveness and security of surgery, postoperative hospital length of stay (LOS), and postoperative status on postoperative day 1 (POD1).

Results: Postoperative status on POD1, such as nasal ventilation, out of bed, headache score, and liquid supplement, had significant improvement (P < 0.05). The median postoperative LOS decreased from 8 days in the control group to 3 days in the ERAS group (P < 0.05). The ERAS group had better economic benefit with fewer hospital charges (P < 0.05). There was no difference in the early postoperative diabetes insipidus and 30-day readmission for epistaxis, hyponatremia, or other complications between the two groups.

Conclusion: The quality of the early postoperative course was improved when a neurosurgical ERAS protocol and minimally invasive endoscopic transsphenoidal pituitary surgery with partially nasal packing were implemented. Endoscopic transsphenoidal pituitary day surgery could be recommended in some classes of patients though further evaluation in large case studies is warranted.

Early vascular modifications after endoscopic endonasal pituitary surgery: The role of OCT-angiography

Purpose

The aim of the present study is to analyze the changes in retinal vessel density (VD), using Optical Coherence Tomography Angiography (OCT-A), in patients that received endoscopic endonasal approach for the removal of an intra-suprasellar pituitary adenoma compressing optic chiasm.

Methods

We evaluated the VD in Superficial Capillary Plexus (SCP), Deep Capillary Plexus (DCP), Radial Peripapillary Capillary (RPC) and the Foveal Avascular Zone (FAZ) area in a series of fourteen patients (7 males, 7 females, mean age 56 ± 13 years), as compared to healthy controls. We also detected the structural Spectral Domain (SD)-OCT parameters: Ganglion Cell Complex (GCC), Retinal Nerve Fiber Layer (RNFL), visual field parameters (Mean Deviation, Pattern Standard Deviation) and Best Corrected Visual Acuity (BCVA). These measurements were performed prior than surgery and 48 hours after.

Results

The patients showed a significant decrease in VD of the macular and papillary regions, a significant increase in FAZ area, a significant impairment in SD-OCT, VF parameters and BCVA respect to 14 eyes of 14 healthy controls (p<0.05), at pre-op evaluation. In patients group the VD in SCP, DCP and RPC increased after surgery respect to baseline but the difference turned to be out statistically significant only in RPC (p = 0.003). Also the BCVA (p = 0.040) and the Mean Deviation at visual field (p = 0.015) significantly improved after surgery. While there was a reduction in structural OCT parameters but it was statistically significant only in GCC (p = 0.039). A positive correlation was found between the preoperative VD of the RPC, Mean Deviation, BCVA and the postoperative Mean Deviation (r = 0.426 p = 0.027; r = 0.624 p = 0.001; r = 0.515 p = 0.006).

Conclusion

OCT-A allows to detect the early changes occurring within 48 hours after surgery showing that the improvement in retinal vessel density could occur before the recovery of the structural OCT parameters and can be a positive predictive factor for the functional recovery.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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