Quantitative Anatomical Comparison of Surgical Approaches to Meckel's Cave.

BACKGROUND: Meckel's cave is a challenging surgical target due to its deep location and proximity to vital neurovascular structures. Surgeons have developed various microsurgical transcranial approaches (MTAs) to access it, but there is no consensus on the best method. Newer endoscopic approaches have also emerged. This study seeks to quantitatively compare these surgical approaches to Meckel's cave, offering insights into surgical volumes and exposure areas. METHODS: Fifteen surgical approaches were performed bilaterally in six specimens, including the pterional approach (PTA), fronto-temporal-orbito-zygomatic approach (FTOZA), subtemporal approach (STA), Kawase approach (KWA), retrosigmoid approach (RSA), retrosigmoid approach with suprameatal extension (RSAS), endoscopic endonasal transpterygoid approach (EETPA), inferolateral transorbital approach (ILTEA) and superior eyelid approach (SEYA). All the MTAs were performed both with 10 mm and 15 mm of brain retraction, to consider different percentages of surface exposure. A dedicated navigation system was used to quantify the surgical working volumes and exposure of different areas of Meckel's cave (ApproachViewer, part of GTx-Eyes II, University Health Network, Toronto, Canada). Microsurgical transcranial approaches were quantified with two different degrees of brain retraction (10 mm and 15 mm). Statistical analysis was performed using a mixed linear model with bootstrap resampling. RESULTS: The RSAS with 15 mm of retraction offered the maximum exposure of the trigeminal stem (TS). If compared to the KWA, the RSA exposed more of the TS (69% vs. 46%; p = 0.01). The EETPA and ILTEA exposed the Gasserian ganglion (GG) mainly in the anteromedial portion, but with a significant 20% gain in exposure provided by the EETPA compared to ILTEA (42% vs. 22%; p = 0.06). The STA with 15 mm of retraction offered the maximum exposure of the GG, with a significant gain in exposure compared to the STA with 10 mm of retraction (50% vs. 35%; p = 0.03). The medial part of the three trigeminal branches was mainly exposed by the EETPA, particularly for the ophthalmic (66%) and maxillary (83%) nerves. The EETPA offered the maximum exposure of the medial part of the mandibular nerve, with a significant gain in exposure compared to the ILTEA (42% vs. 11%; p = 0.01) and the SEY (42% vs. 2%; p = 0.01). The FTOZA offered the maximum exposure of the lateral part of the ophthalmic nerve, with a significant gain of 67% (p = 0.03) and 48% (p = 0.04) in exposure compared to the PTA and STA, respectively. The STA with 15 mm of retraction offered the maximum exposure of the lateral part of the maxillary nerve, with a significant gain in exposure compared to the STA with 10 mm of retraction (58% vs. 45%; p = 0.04). The STA with 15 mm of retraction provided a significant exposure gain of 23% for the lateral part of the mandibular nerve compared to FTOZA with 15 mm of retraction (p = 0.03). CONCLUSIONS: The endoscopic approaches, through the endonasal and transorbital routes, can provide adequate exposure of Meckel's cave, especially for its more medial portions, bypassing the impediment of major neurovascular structures and significant brain retraction. As far as the most lateral portion of Meckel's cave, MTA approaches still seem to be the gold standard in obtaining optimal exposure and adequate surgical volumes.

Neuropsychological Evaluation and Functional Magnetic Resonance Imaging Tasks in the Preoperative Assessment of Patients with Brain Tumors: A Systematic Review.

BACKGROUND: Current surgical treatment of gliomas relies on a function-preserving, maximally safe resection approach. Functional Magnetic Resonance Imaging (fMRI) is a widely employed technology for this purpose. A preoperative neuropsychological evaluation should accompany this exam. However, only a few studies have reported both neuropsychological tests and fMRI tasks for preoperative planning-the current study aimed to systematically review the scientific literature on the topic. METHODS: PRISMA guidelines were followed. We included studies that reported both neuropsychological tests and fMRI. Exclusion criteria were: no brain tumors, underage patients, no preoperative assessment, resting-state fMRI only, or healthy sample population/preclinical studies. RESULTS: We identified 123 papers, but only 15 articles were included. Eight articles focused on language; three evaluated cognitive performance; single papers studied sensorimotor cortex, prefrontal functions, insular cortex, and cerebellar activation. Two qualitative studies focused on visuomotor function and language. According to some authors, there was a strong correlation between performance in presurgical neuropsychological tests and fMRI. Several papers suggested that selecting well-adjusted and individualized neuropsychological tasks may enable the development of personalized and more efficient protocols. The fMRI findings may also help identify plasticity phenomena to avoid unintentional damage during neurosurgery. CONCLUSIONS: Most studies have focused on language, the most commonly evaluated cognitive function. The correlation between neuropsychological and fMRI results suggests that altered functions during the neuropsychological assessment may help identify patients who could benefit from an fMRI and, possibly, functions that should be tested. Neuropsychological evaluation and fMRI have complementary roles in the preoperative assessment.

Comparison of anatomical-based vs. nTMS-based risk stratification model for predicting postoperative motor outcome and extent of resection in brain tumor surgery.

BACKGROUND: Two statistical models have been established to evaluate characteristics associated with postoperative motor outcome in patients with glioma associated to the motor cortex (M1) or the corticospinal tract (CST). One model is based on a clinicoradiological prognostic sum score (PrS) while the other one relies on navigated transcranial magnetic stimulation (nTMS) and diffusion-tensor-imaging (DTI) tractography. The objective was to compare the models regarding their prognostic value for postoperative motor outcome and extent of resection (EOR) with the aim of developing a combined, improved model. METHODS: We retrospectively analyzed a consecutive prospective cohort of patients who underwent resection for motor associated glioma between 2008 and 2020, and received a preoperative nTMS motor mapping with nTMS-based diffusion tensor imaging tractography. The primary outcomes were the EOR and the motor outcome (on the day of discharge and 3 months postoperatively according to the British Medical Research Council (BMRC) grading). For the nTMS model, the infiltration of M1, tumor-tract distance (TTD), resting motor threshold (RMT) and fractional anisotropy (FA) were assesed. For the PrS score (ranging from 1 to 8, lower scores indicating a higher risk), we assessed tumor margins, volume, presence of cysts, contrast agent enhancement, MRI index (grading white matter infiltration), preoperative seizures or sensorimotor deficits. RESULTS: Two hundred and three patients with a median age of 50 years (range: 20-81 years) were analyzed of whom 145 patients (71.4%) received a GTR. The rate of transient new motor deficits was 24.1% and of permanent new motor deficits 18.8%. The nTMS model demonstrated a good discrimination ability for the short-term motor outcome at day 7 of discharge (AUC = 0.79, 95 %CI: 0.72-0.86) and the long-term motor outcome after 3 months (AUC = 0.79, 95 %CI: 0.71-0.87). The PrS score was not capable to predict the postoperative motor outcome in this cohort but was moderately associated with the EOR (AUC = 0.64; CI 0.55-0.72). An improved, combined model was calculated to predict the EOR more accurately (AUC = 0.74, 95 %CI: 0.65-0.83). CONCLUSION: The nTMS model was superior to the clinicoradiological PrS model for potentially predicting the motor outcome. A combined, improved model was calculated to estimate the EOR. Thus, patient counseling and surgical planning in patients with motor-associated tumors should be performed using functional nTMS data combined with tractography.

Surgical management of Glioma Grade 4: technical update from the neuro-oncology section of the Italian Society of Neurosurgery (SINch®): a systematic review.

PURPOSE: The extent of resection (EOR) is an independent prognostic factor for overall survival (OS) in adult patients with Glioma Grade 4 (GG4). The aim of the neuro-oncology section of the Italian Society of Neurosurgery (SINch®) was to provide a general overview of the current trends and technical tools to reach this goal. METHODS: A systematic review was performed. The results were divided and ordered, by an expert team of surgeons, to assess the Class of Evidence (CE) and Strength of Recommendation (SR) of perioperative drugs management, imaging, surgery, intraoperative imaging, estimation of EOR, surgery at tumor progression and surgery in elderly patients. RESULTS: A total of 352 studies were identified, including 299 retrospective studies and 53 reviews/meta-analysis. The use of Dexamethasone and the avoidance of prophylaxis with anti-seizure medications reached a CE I and SR A. A preoperative imaging standard protocol was defined with CE II and SR B and usefulness of an early postoperative MRI, with CE II and SR B. The EOR was defined the strongest independent risk factor for both OS and tumor recurrence with CE II and SR B. For intraoperative imaging only the use of 5-ALA reached a CE II and SR B. The estimation of EOR was established to be fundamental in planning postoperative adjuvant treatments with CE II and SR B and the stereotactic image-guided brain biopsy to be the procedure of choice when an extensive surgical resection is not feasible (CE II and SR B). CONCLUSIONS: A growing number of evidences evidence support the role of maximal safe resection as primary OS predictor in GG4 patients. The ongoing development of intraoperative techniques for a precise real-time identification of peritumoral functional pathways enables surgeons to maximize EOR minimizing the post-operative morbidity.

Idiopathic normal pressure hydrocephalus: postoperative patient perspective and quality of life.

BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a potentially reversible disease. Surgical results have been well described in the literature, but only a few studies investigated the subjective outcome. This study aimed to investigate the patient's expectations about surgery, the perceived improvement after treatment, and its impact on the quality of life (QoL). METHODS: A new dedicated survey was created to investigate subjectively different aspects of the treatment pathway of iNPH (diagnosis, symptoms, expectations from surgery, surgical operation, surgical results, and postoperative QoL), together with the SF-12 and EQ-5D as validated, standardized tools. RESULTS: Forty-five patients were included. Forty-three percent of cases received the diagnosis after at least 1 year, with symptoms worsening in 73%, and frustration in 93%. Reaching a diagnosis was important for 100% of patients, with high expectations from surgery; 86% of them hoped to return to a normal life. Seventy-two percent of patients reported a significant postoperative improvement (walking 68%, mood 57%). Memory and incontinence did not improve in 64% of cases. Subjectively, QoL improved in 72% of cases. The SF-12 score is comparable to controls >75 years, but lower than the 65-75 years group. The EQ-5D index was 0.66 (lower than those of the 65-75 years group = 0.823, and >75 years group = 0.724). Pain and discomfort, instead, were lower compared to the healthy population (43% vs 56%). The idea of having an implanted device and of long-term follow-up is not worrying for 80% of patients; approximately two-thirds of them reported a regained control of their lives. CONCLUSIONS: The importance of early diagnosis and patients' perspective, alongside clinical evaluation, is highlighted. The self-reported evaluations on symptoms and QoL, along with the balance between postoperative worries and benefits, should be discussed preoperatively with patients and relatives, and included postoperatively to comprehensively assess the surgical outcome.

Preliminary Validation of FoRCaSco: A New Grading System for Cerebral and Cerebellar Cavernomas.

OBJECTIVE: Surgical indications for cerebral cavernous malformations (CCMs) remain significantly center- and surgeon-dependent; available grading systems are potentially limited, as they do not include epileptologic and radiologic data. Several experienced authors proposed a new grading system for CCM and the first group of patients capable of providing its statistical validation was analyzed. METHODS: A retrospective series of 289 CCMs diagnosed between 2008 and 2021 was collected in a shared anonymous database among 9 centers. The new grading system ranges from -1 to 10. For each patient with cortical and cerebellar cavernous malformations the grading system was applied, and a retrospective outcome analysis was performed. We proposed a score of 4 as a cutoff for surgical indication. RESULTS: Operated patients with a score ≥4 were grouped with non-operated patients with a score <4, as they constituted the group that received correct treatment according to the new grading system. Patients with a score ≥4, who underwent surgery and had an improved outcome, were compared to patients with a score ≥4 who were not operated (P = 0.04), and to patients with a score <4 who underwent surgery (P < 0.001). CONCLUSIONS: This preliminary statistical analysis demonstrated that this new grading would be applicable in surgical reality. The cutoff score of 4 correctly separated the patients who could benefit from surgical intervention from those who would not. The outcome analysis showed that the treated patients in whom the grading system has been correctly applied have a better outcome than those in whom the grading system has not been applied.

Are convexity meningiomas all the same? A clinico-radiological analysis of surgically treated eloquent areas convexity meningiomas.

BACKGROUND: Convexity meningiomas are considered low-risk tumors, with high possibility of cure and low risk of relapse after resection. Very few studies have investigated meningiomas located in or around highly eloquent regions (namely perirolandic and perisylvian fissures). This study aimed to determine the differences in preoperative characteristics and postoperative outcomes between convexity meningiomas at eloquent area and non-eloquent areas. METHODS: Retrospective study on patients who underwent surgical resection for convexity meningioma. Patients were divided into eloquent and non-eloquent area. Statistical analysis was made comparing preoperative and postoperative data of both groups. RESULTS: The study included a total of 117 patients: 80 with eloquent area tumor and 37 with non-eloquent area tumor. Statistically significant differences were detected between the groups in preoperative KPS (93±10 in eloquent vs. 97±6 in non-eloquent; P=0.008) and in large-caliber vein involvement (76.3% in cases vs. 16.2% in controls; P<0.001). Postoperatively, patients with eloquent area tumors showed initial deterioration in neurological status followed by recovery; final outcomes were comparable to that of patients with non-eloquent area tumors. However, patients with eloquent area meningiomas had higher propensity to suffer from seizures postoperatively. Postoperative complications and long-term outcomes were not significantly different between the two groups. CONCLUSIONS: Patients with eloquent areas convexity meningiomas do not appear to have higher surgical risk. Neurological status is more likely to worsen immediately after surgery, but long-term recovery is satisfactory. Seizure control after surgery appears to be poorer in patients with perirolandic meningioma.

Predicting the Extent of Resection of Motor-Eloquent Gliomas Based on TMS-Guided Fiber Tracking.

BACKGROUND: Surgical planning with nTMS-based tractography is proven to increase safety during surgery. A preoperative risk stratification model has been published based on the M1 infiltration, RMT ratio, and tumor to corticospinal tract distance (TTD). The correlation of TTD with corticospinal tract to resection cavity distance (TRD) and outcome is needed to further evaluate the validity of the model. AIM OF THE STUDY: To use the postop MRI-derived resection cavity to measure how closely the resection cavity approximated the preoperatively calculated corticospinal tract (CST) and how this correlates with the risk model and the outcome. METHODS: We included 183 patients who underwent nTMS-based DTI and surgical resection for presumed motor-eloquent gliomas. TTD, TRD, and motor outcome were recorded and tested for correlations. The intraoperative monitoring documentation was available for a subgroup of 48 patients, whose responses were correlated to TTD and TRD. RESULTS: As expected, TTD and TRD showed a good correlation (Spearman's ρ = 0.67, p < 0.001). Both the TTD and the TRD correlated significantly with the motor outcome at three months (Kendall's Tau-b 0.24 for TTD, 0.31 for TRD, p < 0.001). Interestingly, the TTD and TRD correlated only slightly with residual tumor volume, and only after correction for outliers related to termination of resection due to intraoperative monitoring events or the proximity of other eloquent structures (TTD ρ = 0.32, p < 0.001; TRD ρ = 0.19, p = 0.01). This reflects the fact that intraoperative monitoring (IOM) phenomena do not always correlate with preoperative structural analysis, and that additional factors influence the intraoperative decision to abort resection, such as the adjacency of other vulnerable structures. The TTD was also significantly correlated with variations in motor evoked potential (MEP) responses (no/reversible decrease vs. irreversible decrease; p = 0.03). CONCLUSIONS: The TTD approximates the TRD well, confirming the best predictive parameter and giving strength to the nTMS-based risk stratification model. Our analysis of TRD supports the use of the nTMS-based TTD measurement to estimate the resection preoperatively, also confirming the 8 mm cutoff. Nevertheless, the TRD proved to have a slightly stronger correlation with the outcome as the surgeon's experience, anatomofunctional knowledge, and MEP observations influence the expected EOR.

Hybrid Robotics for Endoscopic Transnasal Skull Base Surgery: Single-Centre Case Series.

BACKGROUND: Only preclinical studies and case reports have described robotic surgery for endoscopic transnasal skull base surgery. OBJECTIVE: To evaluate the role of a novel robotic endoscope holder, developed for transsphenoidal surgery. METHODS: Patients were prospectively enrolled for 3 mo at the Neurosurgery Unit of Brescia. Endoscope Robot® was used to assist during the sphenoidal phase of the approach, tumor removal, and skull base reconstruction. A Likert scale questionnaire was given to all surgeons after each procedure. Patients who underwent robotic-assisted surgery were matched with nonrobotic ones for pathology and type of procedure. All surgical videos were evaluated during bimanual phases. RESULTS: Twenty-one patients underwent robot-assisted, endoscopic transsphenoidal surgery for different pathologies (16 pituitary adenomas, 3 chordomas, 1 craniopharyngioma, 1 pituitary exploration for Cushing disease) for a total of 23 procedures (1 patient underwent 2 endoscopic revisions of a skull base reconstruction). Subjective advantages reported by surgeons included smoothness of movement, image steadiness, and improvement of maneuvers in narrow spaces and with angled endoscopes; as the main limitation, Endoscope Robot® appeared to be relatively heavy during the initial endoscope positioning. A comparative analysis with a historical matched cohort documented similar clinical outcomes, while endoscope lens cleaning and position readjustments were significantly less frequent in robotic procedures. CONCLUSION: Although confirmation in larger studies is needed, Endoscope Robot® was a safe and effective tool, especially advantageous in lengthy interventions through deep and narrow corridors.

Quantitative Anatomic Comparison of Microsurgical Transcranial, Endoscopic Endonasal, and Transorbital Approaches to the Spheno-Orbital Region.

BACKGROUND: The spheno-orbital region (SOR) is a complex anatomic area that can be accessed with different surgical approaches. OBJECTIVE: To quantitatively compare, in a preclinical setting, microsurgical transcranial approaches (MTAs), endoscopic endonasal transpterygoid approach (EEA), and endoscopic transorbital approaches (ETOAs) to the SOR. METHODS: These approaches were performed in 5 specimens: EEA, ETOAs (superior eyelid and inferolateral), anterolateral MTAs (supraorbital, minipterional, pterional, pterional-transzygomatic, and frontotemporal-orbitozygomatic), and lateral MTAs (subtemporal and subtemporal transzygomatic). All specimens underwent high-resolution computed tomography; an optic neuronavigation system with dedicated software was used to quantify working volume and exposed area for each approach. Mixed linear models with random intercepts were used for statistical analyses. RESULTS: Anterolateral MTAs offer a direct route to the greater wings (GWs) and lesser wings (LWs); only they guarantee exposure of the anterior clinoid. Lateral MTAs provide access to a large area corresponding to the GW, up to the superior orbital fissure (SOF) anteriorly and the foramen rotundum medially. ETOAs also access the GW, close to the lateral portion of SOF, but with a different angle of view as compared to lateral MTAs. Access to deep and medial structures, such as the lamina papyracea and the medial SOF, is offered only by EEA, which exposes the LW and GW only to a limited extent. CONCLUSION: This is the first study that offers a quantitative comparison of the most used approaches to SOR. A detailed knowledge of their advantages and limitations is paramount to choose the ideal one, or their combination, in the clinical setting.

An international call for a new grading system for cerebral and cerebellar cavernomas.

Surgical indications for cerebral cavernous malformations remain significantly center- and surgeon-dependent. Available grading systems are potentially limited, as they do not include epileptological and radiological data. A novel grading system is proposed for supratentorial and cerebellar cavernomas: it considers neuroradiological features (bleeding, increase in size), neurological status (focal deficits and seizures), location of the lesion and age of the patient. The score ranges from -1 to 10; furthermore, surgery should be considered when a score of 4 or higher is present. Based on neuroradiological characteristics, 0 points are assigned if the CCM is stable in size at different neuroradiological controls, 1 point if there is an increase in volume during follow-up, 2 points if intra- or extra-lesional bleeding <1 cm is present and 3 points if the CCM produced a hematoma >1 cm. Regarding focal neurological deficits, 0 points are assigned if absent and 2 points if present. For seizures, 0 points are assigned if absent, 1 point if present, but controlled by medications, and 2 points if drug resistant. We considered the site of the CCM, and in case of deep-seated lesions in a critical area (basal ganglia, thalamus) 1 point (-1) is subtracted, while for subcortical or deep cerebellar lesions 0 points are assigned, for CCMs in a cortical critical area 1 point is assigned and in case of lesions in cortical not in critical area or superficial cerebellar area, 2 points are assigned. As far as age is concerned, 0 points are assigned for patients older than 50 years and 1 point for patients younger than 50. In conclusion, a novel grading for surgical decision making in cerebral cavernomas, based on the experience of selected neurosurgeons, basic scientists, and patients, is suggested with the aim of further improving and standardizing the treatment of CCMs. The aim of this paper was also to call for both retrospective and prospective multicenter studies with the aim of testing the efficacy of the grading system in different centers.

Transclival approaches for intradural pathologies: historical overview and present scenario.

Recently, endoscopic transsphenoidal transclival approaches have been developed and their role is widely accepted for extradural pathologies. Their application to intradural pathologies is still debated, but is undoubtedly increasing. In the past five decades, different authors have reported various extracranial, anterior transclival approaches for intradural pathologies. The aim of this review is to provide a historical overview of transclival approaches applied to intradural pathologies. PubMed was searched in October 2018 using the terms transcliv*, cliv* intradural, transsphenoidal transcliv*, transoral transcliv*, transcervical transcliv*, transsphenoidal brainstem, and transoral brainstem. Exclusion criteria included not reporting reconstruction technique, anatomical studies, reviews without new data, and transcranial approaches. Ninety-one studies were included in the systematic review. Since 1966, transcervical, transoral, transsphenoidal microsurgical, and, recently, endoscopic routes have been used as a corridor for transclival approaches to treat intradural pathologies. Each approach presents a curve that follows Scott's parabola, with evident phases of enthusiasm that quickly faded, possibly due to high post-operative CSF leak rates and other complications. It is evident that the introduction of the endoscope has led to a significant increase in reports of transclival approaches for intradural pathologies. Various reconstruction techniques and materials have been used, although rates of CSF leak remain relatively high. Transclival approaches for intradural pathologies have a long history. We are now in a new era of interest, but achieving effective dural and skull base reconstruction must still be definitively addressed, possibly with the use of newly available technologies.

Posttraumatic Vertebral Arteriovenous Fistula: A Lifeline from Tetraplegia?

BACKGROUND: Vertebral artery (VA) rupture is a rare condition that occurs about in 0.5% of cervical trauma. The management of our case was complicated by a spinal epidural hematoma (SEH) leading to worsening neurologic deficits. Only 1 similar case has been reported before in the literature. CASE DESCRIPTION: We report the case of a 37-year-old victim of a serious car accident. Shortly after admission to the emergency department, she developed weakness in all 4 limbs and sensory deficit below T6 level. Cervical spine computed tomography scan revealed an SEH from C1 to T3. Computed tomography angiography scan showed rupture of the left VA at C3 level, with a posttraumatic vertebral arteriovenous fistula at the same level, draining in the epidural venous plexus and to the right jugular internal vein. Immediately after embolization of the left VA, we performed a cervical decompression from C2 to C7. Three months after surgery the patient had a full recovery. CONCLUSIONS: No guidelines exist to treat this situation. We propose consequential steps to treat a posttraumatic cervical SEH with evidence of VA rupture.

The oculomotor neurovascular conflict: Literature review and proposal of management.

BACKGROUND: The Oculomotor nerve (OCN) lies in a close relationship with large arteries inside the basal cisterns. Therefore, it may be compressed by vascular malformations or aneurysms. Nevertheless, the compression is not always related to pathologic conditions. Indeed, some cases of neurovascular conflicts of the OCN have been described in the literature. METHODS: A case of neurovascular conflict of the OCN resolved after steroid treatment is reported. Additionally, a systematic literature review of those cases was performed. RESULTS: OCN palsy due to a neurovascular conflict has been described as acute or chronic persistent palsy, or with an intermittent presentation. Symptoms result from compression, although asymptomatic compression is not uncommon. Surgical treatment, pharmacological treatment, and observation have been reported as options in the literature. Microvascular decompression was employed effectively in some cases of OCN neurovascular conflict. Nevertheless, other cases were treated successfully with steroids (persistent presentation) and carbamazepine (intermittent presentation). A management algorithm based on the results of the literature review is proposed. CONCLUSIONS: Treatment options for OCN neurovascular conflicts and their results are heterogeneous. Based on the literature review, the pharmacological treatment seems to be the most appropriate first-line approach, reserving surgery for refractory cases. Collecting clinical information about new cases will allow defining treatment standards for this rare condition.

Surgical Management of Brain Cavernous Malformations.

Surgical removal of accessible lesions is the only direct therapeutic approach for cerebral cavernous malformations (CCMs). The approach should be carefully evaluated according to clinical, anatomical, and neuroradiological assessment in order to both select the patient and avoid complications. In selected cases, a quantitative anatomical study with a preoperative simulation of surgery could be used to plan the operation. Neuronavigation, ultrasound, and neurophysiologic monitoring are generally required respectively to locate the CCMs and to avoid critical areas. The chapter describes all the possible surgical approaches for supratentorial, infratentorial, deep seated and brain stem CCMs. In any case before performing surgery, the physicians should always consider the benign nature of the lesions and the absolute necessity to avoid not only neurological deficits, but also a neuropsychological impairment that could affect the quality of life of the patients.

Pituitary adenomas and neuropsychological status: a systematic literature review.

Neurocognitive and psychological dysfunctions associated with pituitary adenomas (PAs) are clinically relevant, though probably under-reported. The aim of the current review is to provide an update on neuropsychological status, psychopathology, and perceived quality of life (QoL) in patients with PAs. A systematic research was performed in PubMed and Scopus in order to identify reports on neurocognitive, psychiatric, and psychological disorders in PAs. Prevalence of alterations, QoL evaluation, and used tests were also recorded. PRISMA guidelines were followed. Of 62,448 identified articles, 102 studies were included in the systematic review. The prevalence of neurocognitive dysfunctions was 15-83% in Cushing's Disease (CD), 2-33% in acromegaly, mostly affecting memory and attention. Memory was altered in 22% of nonfunctioning (NF) PAs. Worsened QoL was reported in 40% of CD patients. The prevalence of psychiatric disorders in CD reached 77% and in acromegaly 63%, mostly involving depression, followed by psychosis, and anxiety. The prevalence of psychopathology was up to 83% in CD, and 35% in acromegaly. Postoperative improvement in patients with CD was observed for: learning processes, overall memory, visuospatial skills, and language skills. Short-term memory and psychomotor speed improved in NFPAs. Postoperative improvement of QoL, somatic symptoms, obsessive-compulsive disorder, and coping strategies was seen in CD and acromegaly. Reports after radiotherapy are discordant. There is wide variability in used tests. PAs have been recently shown to be associated with altered neurocognitive and neuropsychological functions, as well as QoL. These data suggest the importance of a multidisciplinary evaluation for an optimal management.

High-Definition 3-Dimensional Exoscope for 5-ALA Glioma Surgery: 3-Dimensional Operative Video.

A 54-yr-old man presented with the radiological recurrence of a glioblastoma at the level of the left anterior cingulate gyrus, 46 mo after first surgery, which had been complicated by bone flap infection. Due to the relatively small recurrence, the long survival, and the good neurological status, surgery was warranted. A new, high-definition (4 K) and 3-dimensional exoscope (ORBEYE; Sony Olympus Medical Solutions Inc, Tokyo, Japan) was used during the surgical approach and throughout tumor removal, which was aided by five-aminolevulinic acid (5-ALA) derived fluorescence. The postoperative course was characterized by supplementary motor area syndrome, which quickly improved, leading to a discharge home 1 wk after surgery. Histological examination confirmed a wild-type (WT) IDH1/2, MGMT (DNA repair enzyme O6-methylguanine-DNA methyltransferase) methylated glioblastoma with a proliferative index focally as high as 20%. He is now being considered for a second-line treatment. As recently reported for spinal surgery,1 we believe this technology has significant potential for its small dimension (which can provide optimal positioning even in ergonomically challenging positions), ease of movement, and image quality, including 5-ALA fluorescence. The patient's consent was obtained for publication.

Quantitative anatomical comparison of transnasal and transcranial approaches to the clivus.

BACKGROUND AND OBJECTIVE: The clivus was defined as "no man's land" in the early 1990s, but since then, multiple approaches have been described to access it. This study is aimed at quantitatively comparing endoscopic transnasal and microsurgical transcranial approaches to the clivus in a preclinical setting, using a recently developed research method. METHODS: Multiple approaches were performed in 5 head and neck specimens that underwent high-resolution computed tomography (CT): endoscopic transnasal (transclival, with hypophysiopexy and with far-medial extension), microsurgical anterolateral (supraorbital, mini-pterional, pterional, pterional transzygomatic, fronto-temporal-orbito-zygomatic), lateral (subtemporal and subtemporal transzygomatic), and posterolateral (retrosigmoid, far-lateral, retrolabyrinthine, translabyrinthine, and transcochlear). An optic neuronavigation system and dedicated software were used to quantify the working volume of each approach and calculate the exposure of different clival regions. Mixed linear models with random intersections were used for statistical analyses. RESULTS: Endoscopic transnasal approaches showed higher working volume and larger exposure compared with microsurgical transcranial approaches. Increased exposure of the upper clivus was achieved by the transnasal endoscopic transclival approach with intradural hypophysiopexy. Anterolateral microsurgical transcranial approaches provided a direct route to the anterior surface of the posterior clinoid process. The transnasal endoscopic approach with far-medial extension ensured a statistically larger exposure of jugular tubercles as compared with other approaches. Presigmoid approaches provided a relatively limited exposure of the ipsilateral clivus, which increased in proportion to their invasiveness. CONCLUSIONS: This is the first anatomical study that quantitatively compares in a holistic way exposure and working volumes offered by the most used modern approaches to the clivus.

Three-Dimensional High-Definition Ventriculoscope: Single-Center Case Series.

OBJECTIVE: Three-dimensional (3D), high-definition (HD) endoscopy has been recently introduced in neurosurgery, and its value has been discussed extensively in endonasal skull base surgery. Because there has been no reported clinical series on the use of a recent 3D-HD ventriculoscope, the aim of this study was to describe our initial experience with this novel device. METHODS: Patients consecutively operated on from June 2016 to June 2018 with a 3D-HD ventriculoscope were prospectively collected. The system is a 6-mm, 0-degree optic with a 105-degree field of view, with a central working channel of 2.2-mm diameter and 2 side channels of 1.3-mm diameter. Patients' demographic data, preoperative symptoms, and neurologic status; neuroradiologic data; type of surgery; operative time; intraoperative and postoperative complications, and follow-up data were prospectively recorded and retrospectively reviewed. RESULTS: Twenty-four patients (age range: 3-84 years) underwent 25 procedures including endoscopic third ventriculocisternostomy, biopsy, and cyst fenestration. The technical goal of surgery was obtained in all patients. There were no intraoperative complications, expect for 1 intraoperative epileptic seizure. Postoperative complications included asymptomatic subdural collections in 2 patients, infection, and delayed endoscopic third ventriculocisternostomy closure in 1 patient each. Relative limits of the system are its size and the availability of only a 0-degree optic. Image quality appeared satisfactory in all procedures. The lack of a dedicated introducer was resolved, exploiting a vascular "peel-away" system. CONCLUSIONS: 3D-HD technology seems to provide potential advantages in ventricular surgery. This initial experience is promising but must be confirmed by larger series.