Decision-making algorithm for minimally invasive approaches to anterior skull base meningiomas

Evolving concepts in meningioma management in the era of genomics

Meningioma is the most common type of primary brain tumor. Surgical resection followed by surveillance is the first-line treatment for the majority of symptomatic meningiomas; however, recent advances in molecular sequencing, DNA methylation, proteomics, and single-cell sequencing provide insights into further characterizing this heterogeneous group of tumors with a wide range of prognoses. A subset of these tumors are highly aggressive and cause severe morbidity and mortality. Therefore, identifying those individuals with a poor prognosis and intervening are critical. This review aims to help readers interpret the molecular profiling of meningiomas to identify patients with worse prognoses and guide the management and strategy for surveillance.

Neuroanatomical insights into neuro-ophthalmic presentations of skull base meningiomas: Pathways to precision medicine - A meta-analysis

Background

Skull base meningiomas are intricately related to neuro-ophthalmic functions and have been related to direct influences on both the afferent and efferent visual pathways due to close contacts with crucial neurovascular structures. The present article reviews the neuro-ophthalmic presentations of these tumors, necessitating the need for precise anatomic information for the delivery of customized diagnostic and therapeutic approaches.

Methods

A literature review was conducted using PubMed and Scopus, focusing on terms related to skull base meningiomas and their neuro-ophthalmic impacts. The review included recent and seminal articles to assess advances in understanding and managing these tumors from an anatomical perspective.

Results

The findings underscore the diversity in neuro-ophthalmic manifestations based on the meningioma's location, affecting visual pathways differently. For instance, meningiomas in the optic nerve sheath typically lead to isolated optic neuropathy and are often managed with radiation therapy. In contrast, those extending from the sphenoid wing require more aggressive approaches like open surgery. This review highlights how the tumor's location dictates the choice of treatment, ranging from conservative management to multidisciplinary surgical interventions.

Conclusion

Proper recognition of the sites of skull base meningiomas results in a treatment tailored to provide therapy aimed explicitly at neuro-ophthalmic outcomes related to the site of the tumors. This approach will not only help to treat effectively but also avoid a wide range of complications and, in turn, increase the effectiveness of the treatment results that a patient will receive. Future studies should aim to refine these anatomical insights toward further advancements in modes of treatment.

Clinical application of transcranial neuroendoscopy combined with supraorbital keyhole approach in minimally invasive surgery of the anterior skull base

To explore the techniques, safety, and feasibility of minimally invasive neurosurgery through the supraorbital eyebrow arch keyhole approach by neuroendoscopy. Retrospective analysis of clinical data of patients with various cranial diseases treated by transcranial neuroendoscopic supraorbital eyebrow keyhole approach in our hospital from March 2021 to October 2023. A total of 39 complete cases were collected, including 21 cases of intracranial aneurysms, 9 cases of intracranial space occupying lesions, 5 cases of brain trauma, 3 cases of cerebrospinal fluid rhinorrhea, and 1 case of cerebral hemorrhage. All patients' surgeries were successful. The good prognosis rate of intracranial aneurysms was 17/21 (81%), and the symptom improvement rate of intracranial space occupying lesions was 8/9 (88.9%). Among them, the initial symptoms of one patient with no improvement were not related to space occupying, while the total effective rate of the other three types of patients was 9/9 (100%). The average length of the craniotomy bone window of the supraorbital eyebrow arch keyhole is 3.77 ± 0.31 cm, and the average width is 2.53 ± 0.23 cm. The average postoperative hospital stay was 14.77 ± 6.59 days. The average clearance rate of hematoma by neuroendoscopy is 95.00% ± 1.51%. Our results indicate that endoscopic surgery through the supraorbital eyebrow arch keyhole approach is safe and effective for the treatment of anterior skull base lesions and cerebral hemorrhage. However, this retrospective study is a single center, small sample study, and the good surgical results do not exclude the subjective screening of suitable patients by clinical surgeons, which may have some bias. Although the clinical characteristics such as indications and contraindications of this surgical method still require further prospective and multicenter clinical research validation, our study still provides a new approach and choice for minimally invasive surgical treatment of anterior skull base lesions.

Interdisciplinary Management of Skull Base Tumors

OBJECTIVE

Endoscopic endonasal skull base surgery has gained acceptance worldwide. Comparative analysis has demonstrated that endoscopic skull base surgery may have advantages for many pathologies of the anterior skull base, e. g., sinonasal malignant tumors; pathologies of the central skull base, e. g., pituitary adenomas, craniopharyngiomas; well-selected cases of planum sphenoidale and tuberculum sellae meningiomas; or for clival lesions, e. g., chordomas, chondrosarcomas, or selected meningiomas. Over the past three decades, interdisciplinary surgical teams, consisting of otolaryngologists and neurosurgeons, have provided detailed anatomical knowledge, suggested new approaches or modifications of established surgical techniques, and offered continued surgical education.

METHOD

A review of pertinent literature was conducted with an emphasis on interdisciplinary endoscopic surgery of skull base lesions.

RESULTS

Based on the authors̓ surgical experience in two different interdisciplinary endoscopic skull base centers, the authors classify approaches for endoscopic endonasal skull base surgery, describe indications, and key anatomic landmarks for common pathologies, and highlight surgical techniques to avoid complications.

CONCLUSION

Interdisciplinary endonasal endoscopic surgery combines surgical expertise, improves resection rates for many pathologies, and minimizes morbidity by reducing the incidence of surgical complications.

Minimally invasive approach for skull base meningiomas

INTRODUCTION

Skull base meningiomas constitute a complex group of skull base tumors. The endoscopic endonasal approaches (EEA) and endoscopic Keyhole have a minimally invasive philosophy with high effectiveness, safety, and a significant decrease in postoperative morbidity in these tumors.

OBJECTIVE

To describe the results of the use of minimally invasive approaches to skull base meningiomas.

METHOD

A descriptive, retrospective study was carried out in 140 patients at the "Hermanos Ameijeiras" Hospital who underwent surgery for cranial base meningiomas using minimally invasive approaches to the cranial base. The degree of tumor resection, tumor recurrence, reinterventions, and complications were evaluated.

RESULTS

ESA were used in 72.8% of the study, while endoscopic Keyholes were used in 26.4% and combined approaches in 0.7%. In relation to total tumor resection, 91.9% was generally achieved. Overall tumor recurrence and reinterventions were less than 8.5% and 4%, respectively. Complications in ESA were: cerebrospinal fluid (CSF) fistula (2.1%), diabetes insipidus, hydrocephalus, cerebral infarction, surgical site hematoma, worsening of cranial nerves I-IV (1.4%) respectively. While in the Keyhole type approaches: seizures (2.9%), hydrocephalus (1.4%), CSF fistula (1.4%), worsening of Nerves IX-XII (0.7%).

CONCLUSIONS

The following study reaffirms that minimally invasive approaches for skull base meningiomas constitute advanced surgical techniques for these tumors, associated with a low rate of postoperative complications.

Extended Unifrontal craniotomy for midline anterior cranial fossa meningiomas: A better shot at preservation of neurovascular structures

Numerous surgical approaches have been described for the resection of anterior cranial fossa meningioma. The common problems associated with these approaches are excessive brain retraction, injury to neurovascular structures, transection of superior sagittal sinus (SSS), and a higher risk of new-onset anosmia. The authors describe a unilateral extended frontal approach with the aim to minimize brain handling without the need for SSS transection and possibly better olfaction preservation.

METHODS

Thirteen patients with anterior cranial fossa meningioma were operated on using the novel technique of unilateral extended frontal skull base approach. The clinical presentation, radiological studies, intraoperative findings, and outcome at follow-up were recorded.

RESULTS

Gross total tumor resection could be achieved in 12 out of 13 patients. At least one of the olfactory tracts could be anatomically preserved in all patients, and superior sagittal sinus was preserved in all patients. Functional olfaction preservation was achieved in 8 patients. No patient developed new-onset anosmia.

CONCLUSIONS

The extended unilateral frontal approach is a viable and reliable alternative for extended bifrontal technique for the resection of large midline anterior cranial fossa meningiomas with avoidance of SSS ligation, decreased brain handling with better olfaction preservation while achieving comparable tumor resection and acceptable cosmetic outcomes.

Anatomical variations of foramen of the diaphragma sellae and neighboring structures: a cadaveric study

The aim of our study was to examine the variations and types of foramen of diaphragma sellae (FDS) and their relationship with nearby surgical landmarks on cadavers.Twenty adult (9 male, 11 female) formalin-fixed cadaveric heads were bilaterally used to analyze the anatomical relationships around the supradiaphragmatic region of sella turcica. Lengths and distances of nearby surgical landmarks were measured by a digital microcaliper. SPSS version 25 was used to analyze the comparison between genders and body sides. Dorsum sellae distances to tuberculum sellae and the optic chiasm(OC) were higher in males than females (p < 0.05). Type 8 infundibulum passage was the most common variation with 50%. There was no finding related to types 1-4 of infundibulum passage. Thus, the present study has indicated that the infundibulum passes mostly from the posterior half of the foramen. The shape of the foramen was irregular in 45%, circular in 20%, sagittally oval in 20%, and horizontally oval in 15% of the cases. The OC was noted normal in 60%, prefixed in 35%, and postfixed in 5% of the cases. Comprehensive anatomical knowledge about the types of the FDS and their neighboring structures is crucial for preoperative planning of sellar region diseases in terms of navigating the region when accessing the foramen. Discrimination of variations of FDS, OC, and pituitary stalk, their relationships, and differences between genders is useful to minimize potential surgical complications.

Fully Endoscopic Supraorbital Approach for Anterior Cranial Base Meningiomas

BACKGROUND

Anterior cranial base meningiomas include those meningiomas originating from the tuberculum sellae, the planum sphenoidale, or the olfactory groove, with surgical excision being the main treatment modality for these tumors. Conventional microscopic and endoscope-assisted versions of the supraorbital keyhole approach via an eyebrow incision emerged into minimally invasive options that are frequently utilized nowadays for treating these tumors. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Notwithstanding, the fully endoscopic or endoscope-controlled version of the supraorbital keyhole approach is not routinely practiced by neurosurgeons, with few series published so far. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic supraorbital approach for anterior cranial base meningiomas.

METHODS

From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic excision of anterior cranial base meningiomas via supraorbital approach were retrieved and analyzed. The pertinent literature was also reviewed.

RESULTS

The surgical technique of the fully endoscopic supraorbital approach for anterior cranial base meningiomas was formulated.

CONCLUSION

The fully endoscopic supraorbital approach for anterior cranial base meningiomas has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Comparison of the Endoscopic Endonasal Approach with the Endoscopic Supraorbital Keyhole Approach to the Tuberculum Sellae Region: A Quantitatively Cadaveric Study

BACKGROUND

 The endoscopic endonasal approach (EEA) and the endoscopic supraorbital keyhole approach (eSKA) provide minimally invasive access to tuberculum sellae (TS) tumors. Evaluation of the operating maneuverability is helpful for approach selection. Herein, we compared the two approaches and aimed to provide quantitative anatomic data for surgical decision-making in the management of TS lesions.

METHODS

 Fifteen dissections were performed on five silicone-injected cadaveric heads. The EEA and eSKA (both right and left) were performed on each head. Surgical freedom and working angles in the axial and sagittal planes were calculated using the stereotactic navigation system in the selected six targets: the midpoint of the leading edge of the sphenoid sinus (leSS), the midpoint of the edge of the dorsum sellae (eDS), the ipsilateral medial opticocarotid recess (imOCR), the contralateral medial opticocarotid recess (cmOCR), the ipsilateral lateral opticocarotid recess (ilOCR), and the contralateral lateral opticocarotid recess (clOCR).

RESULTS

 The surgical freedom at the ilOCR and the axial working angles at the leSS, ilOCR, and imOCR (imOCR with excessive manipulation of the optic apparatus) were greater in the eSKA. The EEA provided greater surgical freedom and/or working angles at most targets than eSKA (the surgical freedom at the imOCR, cmOCR, clOCR, and eDS; the axial working angles at the cmOCR and clOCR; and the sagittal working angles at the leSS, imOCR, cmOCR, clOCR, and eDS).

CONCLUSION

 The EEA provides greater surgical freedom and working angles for paramedian lesions, whereas the eSKA provides better surgical maneuverability for lesions with lateral extension.

Fully Endoscopic Retrosigmoid Approach for Cerebellopontine Angle Tumors

BACKGROUND

Fully endoscopic or endoscope-controlled approaches are essentially keyhole approaches in which rigid endoscopes are the sole visualization tools used during the whole procedure. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Fully endoscopic retrosigmoid approach for cerebellopontine angle tumors is a minimally invasive approach that is not routinely practiced by neurosurgeons, with few series published so far. Unfamiliarity with the technique, steep learning curve, and concerns about inadequate exposure, neurovascular injury, and decreased visibility may explain this fact. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic retrosigmoid approach and present an overview of the published series.

METHODS

From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic retrosigmoid approach for cerebellopontine angle tumors were retrieved and analyzed. The pertinent literature was also reviewed.

RESULTS

The surgical technique of the fully endoscopic retrosigmoid approach was formulated.

CONCLUSION

The endoscopic technique has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Fully Endoscopic Nontubular Retractor Approach for Intraaxial Tumors

BACKGROUND

Fully endoscopic or endoscope-controlled approaches are essentially keyhole approaches in which rigid endoscopes are the sole visualization tools used during the whole procedure. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Fully endoscopic resection of intraparenchymal brain tumors is a minimally invasive approach that is not routinely practiced by neurosurgeons, with a few major series published so far. Unfamiliarity with the technique, steep learning curve, and concerns about inadequate exposure and decreased visibility may explain this fact. The majority of the purely endoscopic resections for intraparenchymal brain lesions are performed nowadays through tubular retractor systems. In very limited instances, however, the fully endoscopic technique is performed without tubular retractors. In this chapter, we elaborate on the surgical technique and nuances of the fully endoscopic nontubular retractor approach for intraaxial tumors.

METHODS

From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, and operative charts and videos of cases undergoing fully endoscopic excision for intraaxial brain tumors were retrieved and analyzed. The pertinent literature was also reviewed.

RESULTS

The surgical technique of the fully endoscopic nontubular retractor approach for intraaxial tumors was formulated.

CONCLUSION

The endoscopic technique has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Meta-analysis of mortality in adults with growth hormone deficiency: Does growth hormone replacement therapy really improve mortality rates?

Growth hormone (GH) deficiency (GHD) is one of the most prevalent deficiencies in patients with hypopituitarism and several cohort studies have demonstrated an increased mortality risk in hypopituitary patients with a presumed GHD. The cause of the excess mortality is most likely multifactorial, including the etiology of the hypopituitarism, non-physiological replacement therapies (mostly glucocorticoid), tumor treatment and its side effects as well as untreated GHD. Several years later, other cohort studies that investigated life expectancy in patients with hypopituitarism on GH replacement therapy (GHRT) that showed a normalized mortality. By comparison of the distribution of characteristics of interest between cohorts, we discuss the existing literature to answer the following question: does growth hormone replacement really improve mortality rates in adult patients with hypopituitarism and GHD? We also conducted a meta-analysis of these studies. Since the literature suffers from selection and time bias (improvement of tumor management and other pituitary hormone replacement therapies), there is no high-quality evidence that replacement therapy for GHD really improves mortality. However, the available data does suggest that GHRT plays a significant part in the normalization of the mortality in patients with hypopituitarism.

Cosmetic Outcomes of Supraorbital Keyhole Craniotomy Via Eyebrow Incision: A Systematic Review and Meta-Analysis

Background  Supraorbital eyebrow craniotomy is a minimally invasive alternative to a frontotemporal craniotomy and is often used for tumor and vascular pathologies. The purpose of this study was to investigate how patient cosmetic outcomes are affected by technique variations of this approach. Methods  PubMed, Embase, and Scopus databases were systematically searched, and results were reported according to PRISMA guidelines. For the meta-analysis portion, the DerSimonian-Laird random effects model was used, and the primary end points were patient satisfaction and percentage of permanent cosmetic complications. Results  A total of 2,629 manuscripts were identified. Of those, 124 studies (8,241 surgical cases) met the inclusion criteria. Overall, 93.04 ± 11.93% of patients reported favorable cosmetic outcome following supraorbital craniotomy, and mean number of cases with permanent cosmetic complications was 6.62 ± 12.53%. We found that vascular cases are associated with more favorable cosmetic outcomes than tumor cases ( p  = 0.0001). Addition of orbital osteotomy or use of a drain is associated with adverse cosmetic outcomes ( p  = 0.001 and p  = 0.0001, respectively). The location of incision, size of craniotomy, utilization of an endoscope, method of cranial reconstruction, skin closure, use of antibiotics, and addition of pressure dressing did not significantly impact cosmetic outcomes ( p  > 0.05 for all). Conclusions  Supraorbital craniotomy is a minimally invasive technique associated with generally high favorable cosmetic outcomes. While certain techniques used in supraorbital keyhole approach do not pose significant cosmetic risks, utilization of an orbital osteotomy and the addition of a drain correlate with unfavorable cosmetic outcomes.

The Impact of Endoscopic Endonasal Surgery on Quality of Life in Patients with Malignant Tumors of the Anterior Skull Base: A Prospective Study

Objective

To investigate the effects of endoscopic endonasal surgery (EES) on longitudinal quality of life (QoL) in patients with malignant tumors of the anterior skull base.

Methods

Eligible patients prospectively completed the Anterior Skull Base Surgery Questionnaire (ASBQ) and the 22-item Sino-Nasal Outcome Test (SNOT-22) questionnaires in referring to 3 different periods throughout their treatment and recovery.

Results

Forty patients were included. The median volume coronal maximum length of the tumor was 3.6 cm (95% CI 2.7-4.1cm). Overall QoL significantly worsened at 1 month postoperatively but returned to baseline after 1 year. Unrelieved symptoms in specific domains prompted further evaluation of individual items. Transient worsening of taste (p=0.011) and olfaction (p=0.004) lasted for 1 month but gradually relieved within the first postoperative year, but vision consistently worsened over the course of the treatment (p=0.126). Age>50 years (p<0.001), comorbidities (p<0.001), tumor necrosis (p<0.001) and recurrence (p=0.001) were associated with worse preoperative QoL. Poor long-term QoL was noted in those undergoing adjuvant therapy (p=0.032). Overall ASBQ scores (p=0.024), subdomain scores in specific symptoms (p=0.016), and vision scores (p=0.009) were worse only in patients with the greater coronal maximum diameter at 1-month postoperatively. Greater coronal maximum diameter was related to worse preoperative subdomain scores regarding specific symptoms (p=0.030) and decreased postoperative long-term decreased vision scores (p=0.014).

Conclusion

Long-term site-specific and sinonasal QoL eventually stabilized after EES. Greater coronal maximum diameter was significantly associated with worsened vision function. Temporarily worse olfactory, vision, and taste function may be tied to decreased short-term QoL.

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.

Olfactory Groove Meningiomas: Comprehensive assessment between the different microsurgical transcranial approaches and the Endoscopic Endonasal Approaches, systematic review and metanalysis on behalf of the EANS skull base section

•OGM surgery is much more complex than a simple debate of "from above or from below" (transcranial vs endoscopic).•Lateral Sub-frontal and Superior Interhemispheric seem the most effective, superior and versatile approaches for OGM.•Minimally Invasive Transcranial approaches showed no inferiority in OGM sized <4 ​cm.•Endoscopic Endonasal Approaches showed inferior results in surgical and in functional outcomes for OGM.

Surgical outcomes and longitudinal quality of life after endoscopic endonasal surgery for anterior skull base meningioma

OBJECTIVE

The objective of this study was to establish the effect of endoscopic endonasal surgery on longitudinal quality of life (QOL) in patients with anterior skull base meningioma.

METHODS

A prospectively collected cohort of consecutively operated anterior skull base meningiomas was analyzed. All cases were performed using the endoscopic endonasal approach (EEA). Sinonasal-specific and overall QOL were measured using the 22-Item Sinonasal Outcome Test and the Anterior Skull Base Questionnaire longitudinally (at 3 weeks, 6 weeks, and 3, 6, and 12 months) across the first postoperative year. The relationship between surgical and QOL outcomes to clinical and radiological characteristics was analyzed using multivariate regression.

RESULTS

Fifty cases were available, with a mean age of 61.5 years and female predominance (74.0%). Visual dysfunction and headache were the most common presenting symptoms, and tumors commonly took origin from the planum (46.0%), tuberculum (44.0%), and olfactory groove (24.0%). Median tumor volume was 4.6 cm3. Visual improvement was noted in 73.1% of cases with preoperative field deficits, while nonimprovement was associated with greater tumor height (p = 0.04). Gross-total resection was not possible in patients with 360° vessel encasement and high-grade cavernous sinus extension with ophthalmoplegia. Postoperative diabetes insipidus was observed only in cases with suprasellar extension. Sinonasal-specific QOL worsened transiently after surgery but returned to baseline levels after 3 weeks. Olfaction and taste scores returned to preoperative baseline scores within the year. Overall QOL at presentation was worse in those with larger tumors (p = 0.04) and visual failure (p = 0.04) and better in those presenting with headache (p = 0.04). Transient worsening of QOL was seen in the first 3 weeks, which returned to baseline by 6 weeks, and then improved to above preoperative levels at 6 months and beyond. Worse QOL at baseline (p = 0.01) and visual improvement (p = 0.01) predicted QOL improvement after surgery.

CONCLUSIONS

Longitudinal QOL in anterior skull base meningioma has been examined for the first time. Endoscopic endonasal surgery improves overall QOL after a transient 3-week worsening due to the sinonasal morbidity of the approach. Visual function is intimately tied to QOL, with worse vision associated with worse preoperative QOL, and QOL improving in parallel with visual restoration after surgery. The EEA is associated with better visual outcomes and should be the preferred approach in accessible tumors.

Endonasal transsphenoidal surgery for planum sphenoidale versus tuberculum sellae meningiomas

OBJECTIVE

The aim of this study was to determine if the distinction between planum sphenoidale (PS) and tuberculum sellae (TS) meningiomas is clinically meaningful and impacts the results of the endoscopic endonasal approach (EEA).

METHODS

A consecutive series of patients who were 18 years of age or older and underwent EEA for newly diagnosed grade I PS meningiomas (PSMs) and TS meningiomas (TSMs) between October 2007 and May 2021 were included. The PS and TS were distinguished by drawing a line passing through the center of the TS and perpendicular to the PS on postcontrast T1-weighted MRI. Probabilistic heatmaps were created to display the actual distribution of tumor volumes. Tumor volume, extent of resection (EOR), visual outcome, and complications were assessed.

RESULTS

The 47 tumors were distributed in a smooth continuum. Using an arbitrary definition, 24 (51%) were PSMs and 23 (49%) were TSMs. The mean volume of PSMs was 5.6 cm3 compared with 4.5 cm3 for TSMs. Canal invasion was present in 87.5% of PSMs and 52% of TSMs. GTR was achieved in 38 (84%) of 45 cases in which it was the goal, slightly less frequently for PSMs (78%) compared with TSMs (91%), although the difference was not significant. Th mean EOR was 99% ± 2% for PSMs and 98% ± 11% for TSMs. Neither the suprasellar notch angle nor the percentage of tumor above the PS impacted the rate of GTR. After a median follow-up of 28.5 months (range 0.1–131 months), there were 2 (5%) recurrences after GTR (n = 38) both of which occurred in patients with PSMs. Forty-two (89%) patients presented with preoperative impaired vision. Postoperative vision was stable or improved in 96% of patients with PSMs and 91% of patients with TSMs. CSF leakage occurred in 4 (16.6%) patients with a PSM, which resolved with only lumbar drainage, and in 1 (4.3%) patient with a TSM, which required reoperation.

CONCLUSIONS

PSM and TSMs arise in a smooth distribution, making the distinction arbitrary. Those classified as PSMs were larger and more likely to invade the optic canals. Surgical outcome for both locations was similar, slightly favoring TSMs. The arbitrary distinction between PSMs and TSMs is less useful at predicting outcome than the lateral extent of the tumor, regardless of the site of origin.

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.

Olfactory Outcomes after Resection of Tuberculum Sella and Planum Sphenoidale Meningiomas via a Transcranial Approach

Objectives Controversy exists surrounding the optimal approaches to tuberculum sella meningioma (TSM) and planum meningioma (PM). Olfaction is infrequently considered within this context but is nonetheless an important quality of life measure. The evolution of olfactory outcomes following contemporary transcranial surgery remains unclear. This study reviews olfactory outcomes after supraorbital craniotomy for TSM or PM and defines temporal trends in its recovery.

Study Design A prospective study of a patients who underwent a minimally invasive supraorbital craniotomy for TSM or PM was conducted at a single neurosurgical center.

Participants & Main Outcome Measures All patients were questioned about olfaction at presentation 3 months postoperatively, 12 months postoperatively, and annually thereafter (median follow-up = 37 months). The olfactory status of patients was categorized as normosmia, anosmia, hyposmia, parosmia, (altered perception of odours), or phantosmia, (olfactory hallucinations).

Results Twenty-two patients were included in the study analysis, (range = 27–76). Precisely, 3 months after surgery, seven patients had normal olfaction (32%). Six patients were anosmic, (27%) four hyposmic, (18%), three parosmic, (14%), and two were phantosmic (9%). At 1-year follow-up, almost half of patients (10; 48%) were normosmic, while two patients (9.5%) were anosmic. There were no further improvements in olfaction between 1 year and long-term follow-up.

Conclusion Subfrontal transcranial approaches for TSM or PM appear to be associated with changes in olfaction that can improve with time; these improvements occur within the first year after surgery. Impacts upon olfaction should be considered when selecting a surgical approach and patients counseled appropriately.

Anterior Skull Base Meningioma: Surgical Approach and Complication Avoidance

Introduction  Endoscopic endonasal approach (EEA) and keyhole transcranial approaches (TCAs) are being increasingly used in anterior skull base meningioma (ASBM) surgery. Objective  We compare tumor resection rates and complication profiles of EEA and supraorbital keyhole approach (SOKHA) with conventional TCAs. Methods  Fifty-four patients with ASBM (olfactory groove meningioma [OGM], n  = 19 and planum sphenoidale/tuberculum sellae meningioma [PSM/TSM], n  = 35) operated at a single center over 7 years were retrospectively analyzed. Results  The overall rate of gross total resection (GTR) was higher in OGM (15/19, 78.9%) than PSM-TSM group (23/35, 65.7%, p  = 0.37). GTR rate with OGM was 90% and 75% with TCA and EEA. Death ( n  = 1) following medical complication (TCA) and cerebrospinal fluid leak requiring re-exploration ( n  = 2, one each in TCA and EEA) accounted for the major complications in OGM. For the PSM/TSM group, the GTR rates were 73.3% ( n  = 11/15), 53.8% ( n  = 7/13), and 71.4% ( n  = 5/7) with TCA, EEA, and SOKHA, respectively. Seven patients (20%) of PSM-TSM developed major postoperative complications including four deaths (one each in TCA and SOKHA, and two in EEA groups) and three visual deteriorations. Direct and indirect vascular complications were common in lesser invasive approaches to PSM-TSM especially if the tumor has encased intracranial arteries. Conclusion  No single approach is applicable to all ASBMs. TCA is still the best approach to obtain GTR but has tissue trauma-related problems. SOKHA may be a good alternative to TCA in selected PSM-TSMs, while EEA may be an alternate option in some OGMs. A meticulous patient selection is needed to derive reported results of EEA for PSM-TSM.

Supraorbital Keyhole Craniotomy via Eyebrow Incision: A Systematic Review and Meta-Analysis

BACKGROUND

Supraorbital eyebrow keyhole craniotomy is a minimally invasive alternative to a frontotemporal craniotomy and is often used for tumor resection and aneurysm clipping. The purpose of this study is to provide a contemporary review on the outcomes related to this approach and to determine whether they vary with the type of pathology and the addition of an endoscope.

METHODS

PubMed, Embase, and Scopus databases were systematically searched, and results were reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. For the meta-analysis portion, the DerSimonian-Laird random effects model was used.

RESULTS

A total of 2629 manuscripts were identified. of those, 124 studies (8241 surgical cases) met the inclusion criteria. Mean total complication rate was 26.7 ± 25.7% and the mean approach-related mortality rate was 1.3 ± 2.8%. Technical success, defined as gross total tumor resection or complete aneurysm clipping, was achieved in 83.6 ± 21.5% of the cases. Vascular pathologies were associated with greater technical success, lower total complications, and longer length of hospital stay compared with tumor cases (P < 0.05 for all). For vascular cases, addition of the endoscope yielded lower technical success (P = 0.001) and lower complication rate (P = 0.041). The use of the endoscope for tumor pathologies did not affect technical success, complications, mortality, length of hospital stay, operative time, or reoperation rate (P > 0.05).

CONCLUSIONS

The supraorbital craniotomy via an eyebrow incision is a feasible minimally invasive approach with an overall high technical success rate for both vascular and tumor pathologies.

Keyhole surgery for giant basal brain tumors. Theoretical explanation with an example of trans-eyebrow subraorbital approach

BACKGROUND

Improvement of modern neurosurgical technology has given rise to keyhole surgery for a wide range of pathologies. Supraorbital trans-eyebrow approach has been described in detail for small tumors of anterior cranial fossa and suprasellar neoplasms. Can we use this small and less traumatic approach for a more complex tumor extending beyond the suprasellar region?

OBJECTIVE

To analyze own experience of surgical treatment of large and giant parasellar tumors via supraorbital approach, to identify the principles of such operations, indications and possible limitations.

MATERIAL AND METHODS

There were 58 resections of parasellar tumors via mini-supraorbital approach had been performed between 2016 and 2021 at the 2nd pediatric neurosurgical department. We selected 42 patients with large and giant tumors extending beyond the chiasmal-sellar zone and causing occlusive hydrocephalus (mean volume 44.2 cm³). Preoperative status of patients, postoperative clinical data and logistics of in-hospital treatment were analyzed.

RESULTS

Total resection was performed in all cases. No redo surgeries or revisions were required. There were no cases of wound infection, CSF leakage and damage to large vessels.

CONCLUSION

We standardized planning of surgeries for large neoplasms considering available knowledge about the nature of diseases, analysis of clinical and X-ray data, goals and objectives of surgery. The reader is offered a theoretical substantiation of applicability of keyhole surgery for chiasmal-sellar tumors on the example of well-known mini-supraorbital approach. We gave certain advices on planning such operations and illustrated clinical examples.

The Role of 3D Tractography in Skull Base Surgery: Technological Advances, Feasibility, and Early Clinical Assessment with Anterior Skull Base Meningiomas

Objective  The aim of this study is to determine feasibility of incorporating three-dimensional (3D) tractography into routine skull base surgery planning and analyze our early clinical experience in a subset of anterior cranial base meningiomas (ACM). Methods  Ninety-nine skull base endonasal and transcranial procedures were planned in 94 patients and retrospectively reviewed with a further analysis of the ACM subset. Main Outcome Measures  (1) Automated generation of 3D tractography; (2) co-registration 3D tractography with computed tomography (CT), CT angiography (CTA), and magnetic resonance imaging (MRI); and (3) demonstration of real-time manipulation of 3D tractography intraoperatively. ACM subset: (1) pre- and postoperative cranial nerve function, (2) qualitative assessment of white matter tract preservation, and (3) frontal lobe fluid-attenuated inversion recovery (FLAIR) signal abnormality. Results  Automated 3D tractography, with MRI, CT, and CTA overlay, was produced in all cases and was available intraoperatively. ACM subset : 8 (44%) procedures were performed via a ventral endoscopic endonasal approach (EEA) corridor and 12 (56%) via a dorsal anteromedial (DAM) transcranial corridor. Four cases (olfactory groove meningiomas) were managed with a combined, staged approach using ventral EEA and dorsal transcranial corridors. Average tumor volume reduction was 90.3 ± 15.0. Average FLAIR signal change was -30.9% ± 58.6. 11/12 (92%) patients (DAM subgroup) demonstrated preservation of, or improvement in, inferior fronto-occipital fasciculus volume. Functional cranial nerve recovery was 89% (all cases). Conclusion  It is feasible to incorporate 3D tractography into the skull base surgical armamentarium. The utility of this tool in improving outcomes will require further study.

Endoscopic Endonasal and Supraorbital Removal of Tuberculum Sellae Meningiomas: Anatomic Guides and Operative Nuances for Keyhole Approach Selection

BACKGROUND

With growing worldwide endoscopy experience, endonasal and supraorbital removal of tuberculum sellae meningiomas (TSM) has increased.

OBJECTIVE

To describe anatomic factors for guiding approach selection and outcomes.

METHODS

Retrospective analysis of patients undergoing endonasal or supraorbital TSM resection: approach criteria, clinical outcomes, acute magnetic resonance imaging (MRI) fluid-attenuated inversion-recovery (FLAIR)/T2 changes.

RESULTS

From 2008 to 2020, 33 patients (mean age 55 ± 11 yr) were identified: 20 (61%) had endonasal and 13 (39%) supraorbital removal. Comparing endonasal and supraorbital approaches, mean tumor volume (3.7 ± 3.5 cm3 vs 7.7 ± 8.5 cm3, P = .07); percent tumor above planum (42% vs 65%, P = .02), and lateral tumor beyond supraclinoid internal carotid arteries (1.4 ± 2.0 mm vs 4.0 ± 3.2 mm, P = .006) were greater for supraorbital route. Sellar depth was greater for endonasal route tumors (12.2 ± 2.6 mm vs 9.3 ± 2.4 mm, P = .003). Endoscopy, used in 10/13(77%) supraorbital cases, was helpful in additional tumor removal in 4/10(40%). Gross total removal and mean volumetric tumor resection were 16/20(80%) and 97.5% by endonasal, and 5/13(39%) and 96% by supraorbital route. Vision improved in 12/17 (71%) endonasal, 6/8 (75%) supraorbital operations, and worsened in 1 (3%) supraorbital case. Endonasal approach with optic canal decompression increased over study period: 15/20 (75%) endonasal patients vs 1/13(8%) supraorbital (P < .001). Postoperative FLAIR/T2 MRI changes occurred in 2/12 supraorbital and 0/20 endonasal cases.

CONCLUSION

In our experience, both endonasal and supraorbital routes are safe and effective for TSM removal. Greater tumor extension below planum and medial optic canal invasion favor endonasal route, while larger size and lateral extension favor supraorbital route. Given high frequency of TSM growth into optic canals and better access for medial optic canal tumor removal, endonasal route may be preferred for most TSMs.

Comparison of Three Surgical Approaches for Frontobasal Meningiomas: Purely Endoscopic Endonasal, Purely Microscopic Bifrontal Transcranial, and Combined Endoscopic and Microscopic Supraorbital Transciliary Approaches

ABSTRACT

Surgical removal of frontobasal meningiomas (FBMs) can be achieved using different techniques, including endoscopic, transcranial, and combined approaches. The advantages and disadvantages of the outcomes of these approaches should be compared to provide the most convenient surgical treatment to the patient. This study aimed to compare 3 surgical approaches for FBMsin terms of outcomes and determine the superiority of each on the basis of anatomical, surgical, and clinical efficacy. Systematic review was performed to identify studies comparing techniques for the surgical removal of FBMs. Each group included 13 patients; 39 patients with FBMshad undergone surgery. These groups were endoscopic endonasal approach (EEA), microscopic bifrontal transcranial approach (MTA), and endoscopic plus microscopic combined supraorbital transciliary approach (STA) groups. Data on the demographics of patient population, pre- and post-operative neurological examination, tumor properties, imaging studies, and surgical complications were extracted. The mean age at the time of surgery for the patient population was 53.2 years. Among the groups, no statistically significant differences were observed with regard to sex (P = 0.582). The mean follow-up time was 56.7 months. A statistically significant difference was observed in the mean tumor volume among the groups; the MTA group showed the highest mean tumor volume. However, no significant difference was found in the mean tumor volume between EEA and STA groups. Regarding operation duration, the STA group had the shortest operation time (mean = 281.5 minutes), whereas the average surgical duration in MTA group was the longest (mean = 443.8 minutes). The average bleeding volume was highest in the MTA group (mean = 746.2 ml) and lowest in the EEA group (mean = 320.8 ml). Tumor removal was incomplete in three patients (two in the EEA group and one in the MTA group). Recurrence was detected in two cases. One patient with recurrence was operated using the endoscopic surgical approach, whereas the other patient underwent the microscopic bifrontal approach. Post-operative hyposmia/anosmia or decreased olfactory function was the most common complication observed in 5 patients, 2 patients each in the EEA and MTA groups and one in the STA group. The second most common complication was wound infection in one patient in the MTA group and two patients in the STA group (7.7%). Both cerebrospinal fluid (CSF) leakage and meningitis were present in two patients (5.1%), one patient each from the EEA and STA groups. Pre-operative visual disturbances were reported in 13 patients (33.3%), all of which resolved post-operatively No statistical differences were found among the groups. Mortality occurred in a patient in the MTA group (2.6%) caused by cardiac arrest on post-operative day 1. This is the first study comparing the surgical outcomes of three surgical approaches for FBMs. Although recent literature suggests that both endoscopic and transcranial approaches have their own advantages and disadvantages, the authors showed that none of the surgical approaches have obvious superiority over the others with regard to outcomes. Thus, the selection of the ideal surgical approach should be based on surgical experience and tumor characteristics.

[Interdisciplinary surgery to the central skull base-current status]

Hintergrund

Die Schädelbasis stellt eine chirurgisch hochkomplexe Einheit dar und ist häufig nur über kombinierte Zugangswege erreichbar. Neu entwickelte Operationstechniken mit Verwendung von mikrochirurgischen Visualisierungsverfahren und aktiven Instrumenten („powered instruments“) sowie „Multi-Port-Zugänge“ ermöglichen neue, weniger traumatische Operationskorridore. Hierfür ist eine enge interdisziplinäre Zusammenarbeit zwischen dem Chirurgen aus dem Fachgebiet der Hals-Nasen-Ohren-Heilkunde sowie dem Neurochirurgen notwendig. Die aktuell etablierten Zugangsverfahren zur zentralen Schädelbasis werden aufgrund eigener klinischer Erfahrungen und unter Berücksichtigung der Entität systematisiert und in Bezug auf die aktuelle Studienlage erörtert.

Material und Methode

Es erfolgte eine retrospektive, qualitative und deskriptive Auswertung der Operationsberichte einzelner Patienten, die in der Zeit zwischen 2006 und 2019 mit Pathologien an der zentralen Schädelbasis chirurgisch gemeinsam von der Neurochirurgie und der Hals-Nasen-Ohren-Heilkunde/Kopf- und Halschirurgie behandelt wurden.

Ergebnisse

Die chirurgischen Zugangswege zur zentralen Schädelbasis ließen sich nachfolgend kategorisieren, teilweise auch in Kombination derselben, als sog. Multi-Port-Zugänge: transnasal-transsphenoidal, subfrontal, subtemporal, transzygomatisch, transpterygonal, transpetrös, translabyrinthär und subokzipital. Maßgebend für die Wahl des Zugangswegs waren die Lokalisation und Art der Pathologie, sowie der mögliche Anspruch auf Funktionserhalt und Komplettentfernung.

Schlussfolgerung

Aufgrund der Komplexität der Strukturen der zentralen Schädelbasis, der unterschiedlichsten Tumorentitäten und der benötigten Fachkompetenz unterschiedlicher Facharztdisziplinen bleibt die Chirurgie der zentralen Schädelbasis eine Herausforderung, der man sich nur an speziellen, nach den Kriterien der Gesellschaft für Schädelbasischirurgie e. V. zertifizierten Kompetenzzentren stellen sollte.

The endoscope-assisted supraorbital "keyhole" approach for anterior skull base meningiomas: an updated meta-analysis

INTRODUCTION

The gold-standard treatment for symptomatic anterior skull base meningiomas is surgical resection. The endoscope-assisted supraorbital "keyhole" approach (eSKA) is a promising technique for surgical resection of olfactory groove (OGM) and tuberculum sellae meningioma (TSM) but has yet to be compared with the microscopic transcranial (mTCA) and the expanded endoscopic endonasal approach (EEA) in the context of existing literature.

METHODS

An updated study-level meta-analysis on surgical outcomes and complications of OGM and TSM operated with the eSKA, mTCA, and EEA was conducted using random-effect models.

RESULTS

A total of 2285 articles were screened, yielding 96 studies (2191 TSM and 1510 OGM patients). In terms of effectiveness, gross total resection incidence was highest in mTCA (89.6% TSM, 91.1% OGM), followed by eSKA (85.2% TSM, 84.9% OGM) and EEA (83.9% TSM, 82.8% OGM). Additionally, the EEA group had the highest incidence of visual improvement (81.9% TSM, 54.6% OGM), followed by eSKA (65.9% TSM, 52.9% OGM) and mTCA (63.9% TSM, 45.7% OGM). However, in terms of safety, the EEA possessed the highest cerebrospinal fluid leak incidence (9.2% TSM, 14.5% OGM), compared with eSKA (2.1% TSM, 1.6% OGM) and mTCA (1.6% TSM, 6.5% OGM). Finally, mortality and intraoperative arterial injury were 1% or lower across all subgroups.

CONCLUSIONS

In the context of diverse study populations, the eSKA appeared not to be associated with increased adverse outcomes when compared with mTCA and EEA and offered comparable effectiveness. Case-selection is paramount in establishing a role for the eSKA in anterior skull base tumours.

Trends in cerebrospinal fluid leak rates following the extended endoscopic endonasal approach for anterior skull base meningioma: a meta-analysis over the last 20 years

OBJECTIVE

The extended endoscopic approach provides unimpaired visualization and direct access to ventral skull base pathology, but is associated with cerebrospinal fluid (CSF) leak in up to 25% of patients. To evaluate the impact of improved surgical techniques and devices to better repair skull base defects, we assessed published surgical outcomes of the extended endoscopic endonasal approach in the last two decades for a well-defined homogenous group of tuberculum sellae and olfactory groove meningioma patients.

METHODS

Random-effects meta-analyses were performed for studies published between 2004 (first publications) and April 2020. We evaluated CSF leak as primary outcome. Secondary outcomes were gross total resection, improvement in visual outcomes in those presenting with a deficit, intraoperative arterial injury, and 30-day mortality. For the main analyses, publications were pragmatically grouped based on publication year in three categories: 2004-2010, 2011-2015, and 2016-2020.

RESULTS

We included 29 studies describing 540 patients with tuberculum sellae and 115 with olfactory groove meningioma. The percentage patients with CSF leak dropped over time from 22% (95% CI: 6-43%) in studies published between 2004 and 2010, to 16% (95% CI: 11-23%) between 2011 and 2015, and 4% (95% CI: 1-9%) between 2016 and 2020. Outcomes of gross total resection, visual improvement, intraoperative arterial injury, and 30-day mortality remained stable over time CONCLUSIONS: We report a noticeable decrease in CSF leak over time, which might be attributed to the development and improvement of new closure techniques (e.g., Hadad-Bassagasteguy flap, and gasket seal), refined multilayer repair protocols, and lumbar drain usage.

Meningiomas of the Planum Sphenoidale and Tuberculum Sella

Patients with meningiomas of the planum sphenoidale and tuberculum sella often present with insidious vision loss in one or both eyes as the only sign or symptom of their disease, although other sensory, oculomotor, and even endocrine abnormalities may be seen in a minority of cases. Incidentally discovered tumors also are common, as patients may undergo neuroimaging for unrelated symptoms or events. Depending on the size and orientation of the tumor, central vision loss from optic nerve compression may be a later sign, and loss of peripheral vision in one or both eyes may not be recognized until it has progressed to areas closer to fixation. A thorough neuroophthalmologic assessment including visual field testing will help to define the extent of optic pathway involvement. Both fundus examination and optical coherence tomography of the retinal nerve fiber layer and macular ganglion cell complex will aid in determining prognosis after treatment of the tumor. Orbital surgery rarely is indicated as primary therapy for meningiomas in this location, and surgical resection or debulking is usually pursued before consideration is given to radiation therapy. Because of the long-term risk of residual tumor growth or recurrence, neuroophthalmic surveillance along with serial neuroimaging is required for years after tumor resection and/or radiation therapy.

Cerebral Anatomy Detection and Surgical Planning in Patients with Anterior Skull Base Meningiomas Using a Virtual Reality Technique

Anterior skull base meningiomas represent a wide cohort of tumors with different locations, extensions, configurations, and anatomical relationships. Diagnosis of these tumors and review of their therapies are inseparably connected with cranial imaging. We analyzed the influence of three-dimensional-virtual reality (3D-VR) reconstructions versus conventional computed tomography (CT) and magnetic resonance imaging (MRI) images (two-dimensional (2D) and screen 3D) on the identification of anatomical structures and on the surgical planning in patients with anterior skull base meningiomas. Medical files were retrospectively analyzed regarding patient- and disease-related data. Preoperative 2D-CT and 2D-MRI scans were retrospectively reconstructed to 3D-VR images and visualized via VR software to detect the characteristics of tumors. A questionnaire of experienced neurosurgeons evaluated the influence of the VR visualization technique on identification of tumor morphology and relevant anatomy and on surgical strategy. Thirty patients were included and 600 answer sheets were evaluated. The 3D-VR modality significantly influenced the detection of tumor-related anatomical structures (p = 0.002), recommended head positioning (p = 0.005), and surgical approach (p = 0.03). Therefore, the reconstruction of conventional preoperative 2D scans into 3D images and the spatial and anatomical presentation in VR models enabled greater understanding of anatomy and pathology, and thus influenced operation planning and strategy.

Eyebrow supraorbital keyhole craniotomy for olfactory groove meningiomas with endoscope assistance: case series and systematic review of extent of resection, quantification of postoperative frontal lobe injury, anosmia, and recurrence

BACKGROUND

Olfactory groove meningiomas (OGMs) are commonly treated with open craniotomy. Endonasal approaches have also been described.

OBJECTIVE

To present clinical and radiographic outcomes for the minimally invasive eyebrow incision supraorbital keyhole approach with endoscopic assistance for OGMs.

METHODS

We performed a retrospective single-center cohort study and a systematic literature review.

RESULTS

Fifteen patients were identified, all with Grade I meningiomas. Radiographic gross total resection of enhancing tumor was achieved in all patients. Mean frontal lobe fluid-attenuated inversion recovery volume decreased from 11.1 ± 18.3 cm³ preoperatively to 9.9 ± 11.4 cm³ immediately postoperatively, and there was minimal new restricted diffusion (3.2 ± 2.2 cm³; max 7.5 cm³). Median length of stay was 3 days (range 2-8). Vision was improved in 4 (80%) and stable in 1 (20%) of 5 patients with a preoperative deficit. New postoperative anosmia occurred in 3 (23%) of 13 patients with any preoperative olfaction. All patients were satisfied with their cosmetic result at 3 months. After a median follow-up of 32.2 months, there were 2 (13.3%) asymptomatic radiographic recurrences, 1 treated with radiosurgery and the other with endoscopic endonasal approach (EEA). No patients required further craniotomy. Systematic review revealed the present series to be the largest to date reporting disaggregated outcomes for the eyebrow approach to OGM.

CONCLUSION

The eyebrow incision supraorbital keyhole craniotomy with endoscopic assistance is a safe and effective approach to OGM with tumor control rates similar to more invasive open approaches and better than the endonasal approach. Rates of frontal lobe injury, CSF leak and anosmia are comparatively low.

The transbasal approach to the anterior skull base: surgical outcome of a single-centre case series

A variety of sinonasal tumours, meningiomas or other lesions of the anterior skull base involve the paranasal sinuses and the periorbital area. The transbasal approach (TBA) has turned out to be a feasible technique to reach those lesions. A retrospective review at a neurosurgical university department between November 2007 and January 2020 with adult patients who underwent resection of oncologic pathologies through TBA. Surgical technique, extent of resection (EOR), clinical outcome and postoperative complications were analysed. 18 TBAs between November 2007 and January 2020 were performed. Median age was 62 (range 25–83), 7 female and 11 male patients. Gross total resection rate was 85.8% throughout all entities. Four (22.2%) patients suffered from WHO°I meningiomas and 14 (77.7%) from other extra-axial lesions. Preoperative Karnofsky Performance Status Scale (KPSS) was 80% (range 40–90), postoperative KPSS 80% (range 20–100). Rate of postoperative complications requiring intervention was 16.7%. Median follow-up was 9.8 (range 1.2–71.8) months. Modifications and extensions of the classic TBA are not mandatory. Complete resection can be performed under functional and cosmetic-preserving aspects. Second-step procedures such as transnasal approaches may be performed to avoid high morbidity of more aggressive TBAs, if necessary. Surgical considerations should be kept simple and straightforward.

Minimally Invasive Approaches to Anterior Skull Base Meningiomas

Objective Anterior skull base meningiomas include olfactory groove, planum sphenoidale, and tuberculum sellae lesions. Traditionally, standard craniotomy approaches have been used to access meningiomas in these locations. More recently, minimally invasive techniques including supraorbital and endonasal endoscopic approaches have gained favor; however there are limited published series comparing the use of these two techniques for these meningiomas. Using our patent database, we identified patients who underwent these two approaches, and conducted a retrospective chart review to compare outcomes between these two techniques.

Methods A total of 32 patients who underwent minimally invasive approaches were identified: 20 supraorbital and 11 endoscopic endonasal. Radiographic images, presenting complaints and outcomes, were analyzed retrospectively. The safety of each approach was evaluated.

Results The mean extent of resection through a supraorbital approach was significantly greater than that of the endoscopic endonasal approach, 88.1 vs. 57.9%, respectively (p = 0.016). Overall, preoperative visual acuity and anopsia deficits were more frequent in the endonasal group that persisted postoperatively (visual acuity: p = 0.004; anopsia: p = 0.011). No major complications including cerebrospinal fluid (CSF) leaks or wound-related complications were identified in the supraorbital craniotomy group, while the endonasal group had two CSF leaks requiring lumbar drain placement. Length of stay was shorter in the supraorbital group (3.4 vs. 6.1 days, p < 0.001).

Conclusion Anterior skull base meningiomas can be successfully managed by both supraorbital and endoscopic endonasal approaches. Both approaches provide excellent direct access to tumor in carefully selected patients and are safe and efficient, but patient factors and symptoms should dictate the approach selected.

Single surgeon experience with minimally invasive supraorbital craniotomy versus bifrontal craniotomy for anterior skull base meningiomas

Background:

Anterior skull base meningiomas (ASBMs) account for about 10% of meningiomas. Bifrontal craniotomy (BFC) represents the traditional transcranial approach to accessing meningiomas in these locations. Supraorbital craniotomy (SOC) provides a minimally invasive subfrontal corridor in select patients. Here, we present our series of ASBM accessed by SOC and BFC by a single surgeon to review decision-making and compare outcomes in both techniques.

Methods:

Thirty-three patients were identified with ASBM. Age, tumor characteristics, presenting symptoms, postoperative complications, and outcomes were analyzed.

Results:

Bifrontal and SOC were performed in 13 and 20 patients, respectively. Mean follow-up time was 98.4 months. Patients undergoing SOC had smaller tumor size, located farther from the posterior table of frontal sinus, had less peritumoral edema, and decreased length of stay compared to patients undergoing BFC. Extent of resection was slightly better with BFC (99.8%) compared to SOC (91.8%), although this difference did not reach statistical significance. Recurrence-free survival and rate of re-do surgeries were not different between two groups. BFC was associated with higher rates of postoperative encephalomalacia.

Conclusion:

SOC provides an excellent surgical option for ASBMs providing comparable extent of resection, minimal manipulation of brain, and excellent cosmetic outcomes for patients. The patient selection is key to maximize the benefits from this approach.

Midline Meningiomas of the Anterior Skull Base: Surgical Outcomes and a Decision-Making Algorithm for Classic Skull Base Approaches

Simple Summary

Resectioning midline meningiomas of the anterior skull base such as olfactory groove, planum sphenoidale, or tuberculum sellae is challenging, and determining the appropriate approach is important. Based on our experience with midline meningiomas, we propose a decision algorithm for choosing suitable transcranial approaches. With dichotomizing classic skull bases approaches into median and lateral ones, we display that median approaches provide satisfactory results for olfactory groove meningiomas, whereas lateral approaches enable sufficient exposure of the visual apparatus for planum sphenoidale meningiomas or tuberculum sellae meningiomas. This manuscript aims to point out the sufficiency and feasibility of classic transcranial techniques.

Abstract

(1) Background: Midline meningiomas such as olfactory groove (OGMs), planum sphenoidale (PSMs), or tuberculum sellae meningiomas (TSMs) are challenging, and determining the appropriate approach is important. We propose a decision algorithm for choosing suitable transcranial approaches. (2) Methods: A retrospective chart review between 06/2007 and 01/2020. Clinical outcomes, radiographic findings, and postoperative complication rates were analyzed with respect to operative approaches. (3) Results: We included 88 patients in the analysis. Of these, 18.2% (16/88) underwent an interhemispheric approach, 72.7% (64/88) underwent a pterional/frontolateral/supraorbital approach, 2.3% (2/88) underwent a unilateral subfrontal approach, and 6.8% (6/88) underwent a bifrontal approach. All OGMs underwent median approaches, along with one PSM. All of the other PSMs and TSMs were resected via lateral approaches. The preoperative tumor volume was ∅20.2 ± 27.1 cm³. Median approaches had significantly higher tumor volume but also higher rates of Simpson I resection (75.0% vs. 34.4%). An improvement of visual deficits was observed in 34.1% (30/88). The adverse event rate was 17.0%. Median follow-up was 15.5 months (range 0–112 months). (4) Conclusions: Median approaches provides satisfying results for OGMs, lateral approaches enable sufficient exposure of the visual apparatus for PSMs and TSMs. In proposing a simple decision-making algorithm, the authors found that satisfactory outcomes can be achieved for midline meningiomas.

The interhemispheric fissure-surgical outcome of interhemispheric approaches

Exposure of the anterior skull base is challenging due to strategic structures. The interhemispheric approach (IHA) has turned out to be a feasible technique. We report our experience with IHAs in patients with extraaxial lesions (EAL). We performed a retrospective chart review at a tertiary neurosurgical center between April 2009 and March 2020. We included patients with resection of EAL through IHAs concentrating on surgical technique, complete resection rate, postoperative outcome, and complications. Seventy-four patients resected by an IHA were included: 49 (66.2%) frontal (FIA), nine (12.1%) parietooccipital (PIA), and 16 (21.6%) frontobasal IHAs (FBIAs). Median age at time of surgery was 59 years (range 16–88 years), 47 (63.5%) female and 27 (36.5%) male. Complete resection rate was 83.8% (FIA 89.8%, PIA 55.6%, FBIA 81.3%). Rate of new minor deficits was 17.6%, rate of major deficits 5.4%, total rate 23.0%. 51 (68.9%) WHO°I meningiomas, ten (13.5%) WHO°II meningiomas, two (2.7%) WHO°III meningiomas, nine (12.2%) metastases, one (1.4%) sarcoma, and one (1.4%) local adenocarcinoma were resected. Total complication rate was 27.0%. Rate of major complications requiring intervention was 9.6%. Mean follow-up was 34.2 (± 33.2) months. In patients with lesions of the interhemispheric fissure, overall morbidity and complications are comparatively high. Extensions of IHAs with potential even higher morbidity are not necessary though; we support the use of standardized IHAs. Our findings suggest regular usage of relatively feasible IHAs for a satisfying outcome. Invasive, complicated, or contralateral trajectories were not needed.

Endoscopic endonasal approach for suprasellar meningiomas: introduction of a new scoring system to predict extent of resection and assist in case selection with long-term outcome data

OBJECTIVE

The endoscopic endonasal approach (EEA) has gained increasing popularity for the resection of suprasellar meningiomas (SSMs). Appropriate case selection is critical in optimizing patient outcome. Long-term outcome data are lacking. The authors systematically identified preoperative factors associated with extent of resection (EOR) and determined the relationship between EOR and long-term recurrence after EEA for SSMs.

METHODS

In this retrospective cohort study, the authors identified preoperative clinical and imaging characteristics associated with EOR and built on the recently published University of California, San Francisco resectability score to propose a score more specific to the EEA. They then examined the relationship between gross-total resection (GTR; 100%), near-total resection (NTR; 95%-99%), and subtotal resection (STR; < 95%) and recurrence or progression with Kaplan-Meier survival analysis.

RESULTS

A total of 51 patients were identified. Radiographic GTR was achieved in 40 of 47 (85%) patients in whom it was the surgical goal. Significant independent risk factors for incomplete resection were prior surgery (OR 25.94, 95% CI < 2.00 to 336.49, p = 0.013); tumor lateral to the optic nerve (OR 13.41, 95% CI 1.82-98.99, p = 0.011); and complete internal carotid artery (ICA) encasement (OR 15.12, 95% CI 1.17-194.08, p = 0.037). Tumor size and optic canal invasion were not significant risk factors after adjustment for other variables. A resectability score based on the multivariable model successfully predicted the likelihood of GTR; a score of 0 had a positive predictive value of 97% for GTR, whereas a score of 2 had a negative predictive value of 87.5% for incomplete resection. After a mean follow-up of 40.6 ± 32.4 months (mean ± SD), recurrence was 2.7% after GTR (1 patient with atypical histology), 44.4% after NTR, and 80% after STR (p < 0.0001). Vision was stable or improved in 93.5% and improved in 67.4% of patients with a preoperative deficit. There were 5 (9.8%) postoperative CSF leaks, of which 4 were managed with lumbar drains and 1 required a reoperation.

CONCLUSIONS

The EEA is a safe and effective approach to SSMs, with favorable visual outcomes in well-selected cases. The combination of postoperative MRI-based EOR with direct endoscopic inspection can be used in lieu of Simpson grade to predict recurrence. GTR dramatically reduces recurrence and can be achieved regardless of tumor size, proximity or encasement of the anterior cerebral artery, or medial optic canal invasion. Risk factors for incomplete resection include prior surgery, tumor lateral to the optic nerve, and complete ICA encasement.

Comparative anatomical analysis between the minipterional and supraorbital approaches

OBJECTIVE

Keyhole approaches, namely the minipterional approach (MPTa) and the supraorbital approach (SOa), are alternatives to the standard pterional approach to treat lesions located in the anterior and middle cranial fossae. Despite their increasing popularity and acceptance, the indications and limitations of these approaches require further assessment. The purpose of the present study was to determine the differences in the area of surgical exposure and surgical maneuverability provided by the MPTa and SOa.

METHODS

The areas of surgical exposure afforded by the MPTa and SOa were analyzed in 12 sides of cadaver heads by using a microscope and a neuronavigation system. The area of exposure of the region of interest and surgical freedom (maneuverability) of each approach were calculated.

RESULTS

The area of exposure was significantly larger in the MPTa than in the SOa (1250 ± 223 mm2 vs 939 ± 139 mm2, p = 0.002). The MPTa provided larger areas of exposure in the ipsilateral and midline compartments, whereas there was no significant difference in the area of exposure in the contralateral compartment. All targets in the anterior circulation had significantly larger areas of surgical freedom when treated via the MPTa versus the SOa.

CONCLUSIONS

The MPTa provides greater surgical exposure and better maneuverability than that offered by the SOa. The SOa may be advantageous as a direct corridor for treating lesions located in the contralateral side or in the anterior cranial fossa, but the surgical exposure provided in the midline region is inferior to that exposed by the MPTa.

Endoscopic transorbital surgery for Meckel's cave and middle cranial fossa tumors: surgical technique and early results

OBJECTIVE

Tumors involving Meckel's cave remain extremely challenging because of the surrounding complex neurovascular structures and deep-seated location. The authors investigated a new minimal-access technique using the endoscopic transorbital approach (eTOA) through the superior eyelid crease to Meckel's cave and middle cranial fossa lesions and reviewed the most useful surgical procedures and pitfalls of this approach.

METHODS

Between September 2016 and January 2018, the authors performed eTOA in 9 patients with tumors involving Meckel's cave and the middle cranial fossa. The lesions included trigeminal schwannoma in 4 patients, meningioma in 2 patients, metastatic brain tumor in 1 patient, chondrosarcoma in 1 patient, and dermoid cyst in 1 patient. In 7 of the 9 patients, eTOA alone was performed, while the other 2 patients underwent a combined eTOA and endoscopic endonasal approach or retrosigmoid craniotomy. Data including details of surgical techniques and clinical outcomes were recorded.

RESULTS

Gross-total resection was performed in 7 of the 9 patients (77.8%). Four patients underwent extended eTOA (with lateral orbital rim osteotomy). Drilling of the trapezoid sphenoid floor, a middle fossa "peeling" technique, and full visualization of Meckel's cave were applied to approach the lesions. Tumors were exposed and removed extradurally in 3 patients and intradurally in 6 patients. There was no postoperative CSF leak.

CONCLUSIONS

The eTOA affords a direct route to access Meckel's cave and middle cranial fossa lesions. With experience, this novel approach can be successfully applied to selected skull base lesions. To achieve successful removal of the tumor, emphasis should be placed on the importance of adequately removing the greater sphenoid wing and vertical crest. However, because of limited working space eTOA may not be an ideal approach for posterior fossa lesions.

Preservation of olfaction in anterior midline skull base meningiomas: a comprehensive approach

BACKGROUND

Olfaction is an undervalued sense in neurosurgery. Attempted surgical resection of anterior cranial fossa meningiomas puts the olfactory pathway at risk. Preservation of olfaction may increase the postoperative quality of life. Objective assessment of olfaction may inform clinical decision-making and influence the selection of operative approaches for surgical resection.

METHODS

We reviewed all patients who underwent surgical resection for midline anterior skull base meningiomas from July 1, 2014, through December 31, 2017. Patient demographics, tumor size, operative approach, pre- and postoperative deficits, and Simpson grade were collected and analyzed. Postoperative olfaction was assessed by clinical evaluation as well as objective evaluation using the University of Pennsylvania Smell Identification Test (UPSIT).

RESULTS

Twenty-eight patients (10 male, 18 female) were included with an average age of 53.8 years (range 27-80 years). Twenty-six patients underwent craniotomy for resection, while 2 patients had endoscopic approaches. Average tumor volume was 402.1 cm³ (6.6-2507.7 cm³). Preoperatively, five patients (17.8%) presented with olfactory impairment. Objectively, 50% of patients (14/28) consented and completed the UPSIT. The average postoperative UPSIT score was 25.8/40 (9/40-38/40). Two patients not identified on clinical assessment alone demonstrated postoperative olfactory deficit on UPSIT (2/14).

CONCLUSION

There are limited published studies evaluating olfaction in patients who undergo skull-based approaches for anterior fossa meningiomas. Our series showed the highest olfaction preservation rate (87.5%) using a comprehensive strategy and multitude of surgical approaches based on the olfactory function and tumor characteristics.