Establishing connectivity through microdissections of midbrain stimulation-related neural circuits.

Comprehensive understanding of the neural circuits involving the ventral tegmental area is essential for elucidating the anatomofunctional mechanisms governing human behaviour, in addition to the therapeutic and adverse effects of deep brain stimulation for neuropsychiatric diseases. Although the ventral tegmental area has been targeted successfully with deep brain stimulation for different neuropsychiatric diseases, the axonal connectivity of the region is not fully understood. Here, using fibre microdissections in human cadaveric hemispheres, population-based high-definition fibre tractography and previously reported deep brain stimulation hotspots, we find that the ventral tegmental area participates in an intricate network involving the serotonergic pontine nuclei, basal ganglia, limbic system, basal forebrain and prefrontal cortex, which is implicated in the treatment of obsessive-compulsive disorder, major depressive disorder, Alzheimer's disease, cluster headaches and aggressive behaviours.

Unveiling the axonal connectivity between the precuneus and temporal pole: Structural evidence from the cingulum pathways.

Neuroimaging studies have consistently demonstrated concurrent activation of the human precuneus and temporal pole (TP), both during resting-state conditions and various higher-order cognitive functions. However, the precise underlying structural connectivity between these brain regions remains uncertain despite significant advancements in neuroscience research. In this study, we investigated the connectivity of the precuneus and TP by employing parcellation-based fiber micro-dissections in human brains and fiber tractography techniques in a sample of 1065 human subjects and a sample of 41 rhesus macaques. Our results demonstrate the connectivity between the posterior precuneus area POS2 and the areas 35, 36, and TG of the TP via the fifth subcomponent of the cingulum (CB-V) also known as parahippocampal cingulum. This finding contributes to our understanding of the connections within the posteromedial cortices, facilitating a more comprehensive integration of anatomy and function in both normal and pathological brain processes. PRACTITIONER POINTS: Our investigation delves into the intricate architecture and connectivity patterns of subregions within the precuneus and temporal pole, filling a crucial gap in our knowledge. We revealed a direct axonal connection between the posterior precuneus (POS2) and specific areas (35, 35, and TG) of the temporal pole. The direct connections are part of the CB-V pathway and exhibit a significant association with the cingulum, SRF, forceps major, and ILF. Population-based human tractography and rhesus macaque fiber tractography showed consistent results that support micro-dissection outcomes.

Repeat stereotactic radiosurgery for progressive vestibular schwannomas after primary gamma knife radiosurgery.

PURPOSE: Limited data provides guidance on the management of vestibular schwannomas (VSs) that have progressed despite primary Gamma Knife radiosurgery (GKRS). The present article reports our long-term experience after repeat GKRS for VS with sustained progression after solely primary GKRS management. METHODS: A retrospective review of 1997 patients managed between 1987 and 2023 was conducted. Eighteen patients had sustained tumor progression after primary GKRS and underwent repeat GKRS. The median repeat GKRS margin dose was 11 Gy (IQR: 11-12), the median tumor volume was 2.0 cc (IQR: 1.3-6.3), and the median cochlear dose in patients with preserved hearing was 3.9 Gy (IQR: 3-4.1). The median time between initial and repeat GKRS was 65 months (IQR: 38-118). RESULTS: The median follow-up was 70 months (IQR: 23-101). After repeat GKRS, two patients had further tumor progression at 4 and 21 months and required partial resection of their tumors. The 10-year actuarial tumor control rate after repeat GKRS was 88%. Facial nerve function was preserved in 13 patients who had House-Brackmann grade 1 or 2 function at the time of repeat GKRS. Two patients with serviceable hearing preservation (Gardner-Robertson grade 1 or 2) at repeat GKRS retained that function afterwards. In patients with tinnitus, vestibular dysfunction, and trigeminal neuropathy, symptoms remained stable or improved for 16/16 patients, 12/15 patients, and 10/12 patients, respectively. One patient developed facial twitching in the absence of tumor growth 21 months after repeat GKRS. CONCLUSIONS: Repeat GKRS effectively controlled tumor growth and preserved cranial nerve outcomes in most patients whose VS had sustained progression after initial primary radiosurgery.

The detrimental effect of biopsy preceding resection in surgically accessible glioblastoma: results from the national cancer database.

PURPOSE: Aggressive resection in surgically-accessible glioblastoma (GBM) correlates with improved survival over less extensive resections. However, the clinical impact of performing a biopsy before definitive resection have not been previously evaluated. METHODS: We analyzed 17,334 GBM patients from the NCDB from 2010-2014. We categorized them into: "upfront resection" and "biopsy followed by resection". The outcomes of interes included OS, 30-day readmission/mortality, 90-day mortality, and length of hospital stay (LOS). The Kaplan-Meier methods and accelerated failure time (AFT) models were applied for survival analysis. Multivariable binary logistic regression were performed to compare differences among groups. Multiple imputation and propensity score matching (PSM) were conducted for validation. RESULTS: "Upfront resection" had superior OS over "biopsy followed by resection" (median OS:12.4 versus 11.1 months, log-rank p = 0.001). Similarly, multivariable AFT models favored "upfront resection" (time ratio[TR]:0.83, 95%CI: 0.75-0.93, p = 0.001). Patients undergoing "upfront gross-total resection (GTR)" had higher OS over "upfront subtotal resection (STR)", "GTR following STR", and "GTR or STR following initial biopsy" (14.4 vs. 10.3, 13.5, 13.3, and 9.1 months;TR: 1.00 [Ref.], 0.75, 0.82, 0.88, and 0.67). Recent years of diagnosis, higher income, facilities located in Southern regions, and treatment at academic facilities were significantly associated with the higher likelihood of undergoing upfront resection. Multivariable regression showed a decreased 30 and 90-day mortality for patients undergoing "upfront resection", 73% and 44%, respectively (p < 0.001). CONCLUSIONS: Pre-operative biopsies for surgically accessible GBM are associated with worse survival despite subsequent resection compared to patients undergoing upfront resection.

Sonodynamic therapy for adult-type diffuse gliomas: past, present, and future.

BACKGROUND: Intra-axial brain tumors persist as significant clinical challenges. Aggressive surgical resection carries risk of morbidity, and the blood-brain barrier (BBB) prevents optimal pharmacological interventions. There is a clear clinical demand for innovative and less invasive therapeutic strategies for patients, especially those that can augment established treatment protocols. Focused ultrasound (FUS) has emerged as a promising approach to manage brain tumors. Sonodynamic therapy (SDT), a subset of FUS, utilizes sonosensitizers activated by ultrasound waves to generate reactive oxygen species (ROS) and induce tumor cell death. OBJECTIVE: This review explores the historical evolution and rationale behind SDT, focusing on its mechanisms of action and potential applications in brain tumor management. METHOD: A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Preclinical studies have demonstrated the efficacy of various sonosensitizers, including 5-aminolevulinic acid (5-ALA), fluorescein, porphyrin derivatives, and nanoparticles, in conjunction with FUS for targeted tumor therapy and BBB disruption. Clinical trials have shown promising results in terms of safety and efficacy, although further research is needed to fully understand the potential adverse effects and optimize treatment protocols. Challenges such as skull thickness affecting FUS penetration, and the kinetics of BBB opening require careful consideration for the successful implementation of SDT in clinical practice. Future directions include comparative studies of different sonosensitizers, optimization of FUS parameters, and exploration of SDT's immunomodulatory effects. CONCLUSION: SDT represents a promising frontier in the treatment of aggressive brain tumors, offering hope for improved patient outcomes.

Gamma knife radiosurgery for clival metastasis: case series and systematic review.

PURPOSE: Clival metastatic cancer is rare and has limited literature to guide management. We describe management of clival metastasis with Gamma Knife radiosurgery (GKRS). We augment our findings with a systematic review of all forms of radiation therapy for clival metastasis. METHODS: Records of 14 patients with clival metastasis who underwent GKRS at the University of Pittsburgh Medical Center from 2002 to 2023 were reviewed. Treatment parameters and clinical outcomes were assessed. A systematic review was conducted using evidence-based guidelines. RESULTS: The average age was 61 years with male predominance (n = 10) and average follow-up of 12.4 months. The most common primary cancers were prostate (n = 3) and lung (n = 3). The average time from cancer diagnosis to clival metastasis was 34 months. The most common presenting symptoms were headache (n = 9) and diplopia (n = 7). Five patients presented with abducens nerve palsies, and two presented with oculomotor nerve palsies. The median tumor volume was 9.3 cc, and the median margin dose was 15 Gy. Eleven patients achieved tumor control after one procedure, and three with progression obtained tumor control after repeat GKRS. One patient recovered abducens nerve function. The median survival from cancer diagnosis and GKRS were 49.7 and 15.3 months, respectively. The cause of death was progression of systemic cancer in six patients, clival metastasis in one, and unknown in four. The systematic review included 31 studies with heterogeneous descriptions of treatment and outcomes. CONCLUSION: Clival metastasis is rare and associated with poor prognosis. GKRS is a safe, effective treatment for clival metastasis.

Complications and visual outcomes following surgical resection of pediatric optic pathway/hypothalamic gliomas: a systematic review and meta-analysis.

Pediatric optic pathway/hypothalamic gliomas (OPHG) pose challenges in treatment due to their location and proximity to vital structures. Surgical resection plays a key role in the management of OPHG especially when the tumor exhibits mass effect and causes symptoms. However, data regarding outcomes and complications of surgical resection for OPHG remains heterogenous. The authors performed a systematic review on pediatric OPHG in four databases: PubMed, EMBASE, Cochrane Library, and Google Scholar. We included studies that reported on the visual outcomes and complications of OPHG resection. A meta-analysis was performed and reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 26 retrospective studies were included. Seven hundred ninety-seven pediatric patients with OPHG undergoing surgical resection were examined. A diagnosis of NF1 was confirmed in 9.7%. Gross total resection was achieved in 36.7%. Intraorbital optic pathway gliomas showed a significantly higher gross total resection rate compared to those located in the chiasmatic/hypothalamic region (75.8% vs. 9.6%). Postoperatively, visual acuity improved in 24.6%, remained unchanged in 68.2%, and worsened in 18.2%. Complications included hydrocephalus (35.4%), anterior pituitary dysfunction (19.6%), and transient diabetes insipidus (29%). Tumor progression post-resection occurred in 12.8%, through a mean follow-up of 53.5 months. Surgical resection remains an essential strategy for treating symptomatic and large pediatric OPHG and can result in favorable vision outcomes in most patients. Careful patient selection is critical. Patients should be monitored for hydrocephalus development postoperatively and followed up to assess for tumor progression and adjuvant treatment necessity.

Sodium fluorescein-guided resection of brain metastases: A needed approach or an option? A systematic review and meta-analysis.

PURPOSE: Brain metastases (BM) often leave residual tumors despite having visible margins, which increases the risk of local tumor recurrence and can impact overall patient survival rates. Fluorescence-guided surgery (FGS) utilizing sodium fluorescein (FL) has been reported as an effective technique in recent studies. This study aimed to evaluate the efficacy of FL FGS in improving the extent of resection of brain metastases and its impact on overall survival. METHODS: We conducted a systematic search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Our primary focus was on gross total resection (GTR). Additionally, we extracted survival data and evaluated the risk of bias using a modified version of the Joanna Briggs Institute critical appraisal tool. RESULTS: The study comprised 970 patients with brain metastases through eight different studies. The study found that patients who underwent FL-guided resection had a significantly higher rate of GTR (OR: 2.02, 95% CI: 1.14-3.56, p = 0.0156, I2 = 41.5%). Additionally, the study concluded that FL-guided resection is associated with better overall survival rates (HR: 0.61, 95%CI: 0.47 0.80, p = 0.0003, I2 = 41.5%). CONCLUSION: Our research suggests that the use of FL is associated with a higher rate of GTR and improved overall patient survival. None of the studies we reviewed reported significant complications associated with the use of FL in patients.

Phase II study of border zone stereotactic radiosurgery with bevacizumab in patients with recurrent or progressive glioblastoma multiforme.

PURPOSE: Recurrent glioblastoma is universally fatal with limited effective treatment options. The aim of this phase 2 study of Border Zone SRS plus bevacizumab was to evaluate OS in patients with recurrent GBM. METHODS: Patients with histologically confirmed GBM with recurrent disease who had received prior first-line treatment with fractionated radiotherapy and chemotherapy and eligible for SRS were enrolled. Bevacizumab 10 mg/kg was given day -1, day 14, and then every 14 days until disease progression. 1-14 days before BZ-SRS procedure, patients underwent brain MRI /MRS. MRS with measurement of choline-to-N-acetyl aspartate index (CNI) area ≥ 3 was targeted for SRS. RESULTS: From 2015-2017, sixteen of planned 40 patients were enrolled. The median age was 62 (range, 48-74Y). 3/16 (0.188) participants experienced grade 2 toxicity. No AREs were reported. The mOS was 11.73 months compared to 8.74 months (P = 0.324) from date of SRS for the BZ-SRS and institutional historical controls, respectively. PFS-6 and OS-6 were 31.2% (p = 0.00294) and 81.2%(p = 0.058), respectively. Of 13 evaluable for best response: 1 CR (p = 0.077), 4 PR (p = 0.308), 7 SD (p = 0.538), and 1 PD (p = 0.077). 11/16 participants had MRS scans with an estimated probability that MRS changes a treatment plan of 0 (0, 0.285). CONCLUSION: BZ-SRS with bevacizumab was feasible and well tolerated. There is no significant survival benefit using BZ-SRS with bevacizumab compared to institutional historical controls. Secondary analysis revealed a trend toward improved PFS-6, but not OS-6 after BZ-SRS. MRS scans did not result in changes to SRS treatment plans.

Stereotactic radiosurgery for patients with brain metastases from gastroesophageal cancers.

BACKGROUND: The prognosis of patients with brain metastases from gastroesophageal (GE) cancers remains unclear despite recent advances in systemic therapies. The authors present a large single-institution experience in the use of stereotactic radiosurgery (SRS). METHODS: A retrospective review of 71 GE cancer patients (64 male, 90.14%) who underwent Gamma Knife SRS was conducted. Overall, 243 brain metastases were treated and the median number of metastases per patient was 2 (range:1-21). The median age at SRS was 66 years (range: 26-85) and the median treatment day KPS was 80 (range: 50-100). The median cumulative tumor volume was 6.7 cc (range: 0.27-104.76) and the median single-session margin dose was 18 Gy (range: 12-20). RESULTS: The median overall survival after SRS was 7 months (range: 1-64). At last follow up, 54 (76.06%) patients were deceased, 8 of whom (14.81%) expired secondary to their intracranial metastases. Four patients (5.63%) experienced local tumor progression at a median time of 8 months (range: 2-13) after SRS. Ten patients (14%) experienced new remote tumor development at a median time of 4 months (range: 0-14) after SRS. Whole-brain radiation therapy (2 patients, 20%) and repeat SRS (8 patients, 80%) were used for newly developed tumors. The incidence of transient adverse radiation effects was 8.45%. CONCLUSIONS: In this study, the 12-month local tumor control rate was 90%. Incidences of adverse radiation effect rates were rare. The median overall survival of 7 months indicates the poor prognosis of patients with brain spread of their GE cancer.

Stereotactic radiosurgery outcome for deep-seated cerebral arteriovenous malformations in the brainstem and thalamus/basal ganglia: systematic review and meta-analysis.

Deep-seated unruptured AVMs located in the thalamus, basal ganglia, or brainstem have a higher risk of hemorrhage compared to superficial AVMs and surgical resection is more challenging. Our systematic review and meta-analysis provide a comprehensive summary of the stereotactic radiosurgery (SRS) outcomes for deep-seated AVMs. This study follows the guidelines set forth by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Statement. We conducted a systematic search in December 2022 for all reports of deep-seated arteriovenous malformations treated with SRS. Thirty-four studies (2508 patients) were included. The mean obliteration rate in brainstem AVM was 67% (95% CI: 0.60-0.73), with significant inter-study heterogeneity (tau2 = 0.0113, I2 = 67%, chi2 = 55.33, df = 16, p-value < 0.01). The mean obliteration rate in basal ganglia/thalamus AVM was 65% (95% CI: 0.58-0.72) with significant inter-study heterogeneity (tau2 = 0.0150, I2 = 78%, chi2 = 81.79, df = 15, p-value < 0.01). The presence of deep draining veins (p-value: 0.02) and marginal radiation dose (p-value: 0.04) were positively correlated with obliteration rate in brainstem AVMs. The mean incidence of hemorrhage after treatment was 7% for the brainstem and 9% for basal ganglia/thalamus AVMs (95% CI: 0.05-0.09 and 95% CI: 0.05-0.12, respectively). The meta-regression analysis demonstrated a significant positive correlation (p-value < 0.001) between post-operative hemorrhagic events and several factors, including ruptured lesion, previous surgery, and Ponce C classification in basal ganglia/thalamus AVMs. The present study found that radiosurgery appears to be a safe and effective modality in treating brainstem, thalamus, and basal ganglia AVMs, as evidenced by satisfactory rates of lesion obliteration and post-surgical hemorrhage.

Fluorescence-guided resection of intradural spinal tumors: a systematic review and meta-analysis.

Intradural spinal tumors present significant challenges due to involvement of critical motor and sensory tracts. Achieving maximal resection while preserving functional tissue is therefore crucial. Fluorescence-guided surgery aims to improve resection accuracy and is well studied for brain tumors, but its efficacy has not been fully assessed for spinal tumors. This meta-analysis aims to delineate the efficacy of fluorescence guidance in intradural spinal tumor resection. The authors performed a systematic review in four databases. We included studies that have utilized fluorescence agents, 5-aminolevulinic acid (5-ALA) or sodium fluorescein, for the resection of intradural spinal tumors. A meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 12 studies involving 552 patients undergoing fluorescence-guided intradural spinal tumor resection were included. Meningiomas demonstrated a 98% fluorescence rate and were associated with a homogenous florescence pattern; however, astrocytomas had variable fluorescence rate with pooled proportion of 70%. There was no significant difference in gross total resection (GTR) rates between fluorescein and 5-ALA (94% vs 84%, p = .22). Pre-operative contrast enhancement was significantly associated with intraoperative fluorescence with fluorescein. Intramedullary tumors with positive intraoperative fluorescence were significantly associated with higher GTR rates (96% vs 73%, p = .03). Utilizing fluorescence guidance during intradural spinal tumor resection holds promise of improving intraoperative visualization for specific intradural spinal tumors. Meningiomas and ependymomas have the highest fluorescence rates especially with sodium fluorescein; on the other hand, astrocytomas have variable fluorescence rates with no superiority of either agent. Positive fluorescence of intramedullary tumors is associated with a higher degree of resection.

Standardized intraoperative 5-ALA photodynamic therapy for newly diagnosed glioblastoma patients: a preliminary analysis of the INDYGO clinical trial.

PURPOSE: Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. The unfavorable prognosis despite maximal therapy relates to high propensity for recurrence. Thus, overall survival (OS) is quite limited and local failure remains the fundamental problem. Here, we present a safety and feasibility trial after treating GBM intraoperatively by photodynamic therapy (PDT) after 5-aminolevulinic acid (5-ALA) administration and maximal resection. METHODS: Ten patients with newly diagnosed GBM were enrolled and treated between May 2017 and June 2018. The standardized therapeutic approach included maximal resection (near total or gross total tumor resection (GTR)) guided by 5-ALA fluorescence-guided surgery (FGS), followed by intraoperative PDT. Postoperatively, patients underwent adjuvant therapy (Stupp protocol). Follow-up included clinical examinations and brain MR imaging was performed every 3 months until tumor progression and/or death. RESULTS: There were no unacceptable or unexpected toxicities or serious adverse effects. At the time of the interim analysis, the actuarial 12-months progression-free survival (PFS) rate was 60% (median 17.1 months), and the actuarial 12-months OS rate was 80% (median 23.1 months). CONCLUSIONS: This trial assessed the feasibility and the safety of intraoperative 5-ALA PDT as a novel approach for treating GBM after maximal tumor resection. The current standard of care remains microsurgical resection whenever feasible, followed by adjuvant therapy (Stupp protocol). We postulate that PDT delivered immediately after resection as an add-on therapy of this primary brain cancer is safe and may help to decrease the recurrence risk by targeting residual tumor cells in the resection cavity. Trial registration NCT number: NCT03048240. EudraCT number: 2016-002706-39.

Fluorescence guided surgery for pituitary adenomas.

PURPOSE: Resection of pituitary adenomas presents a number of unique challenges in neuro-oncology. The proximity of these lesions to key vascular and endocrine structures as well as the need to interpret neuronavigation in the context of shifting tumor position increases the complexity of the operation. More recently, substantial advances in fluorescence-guided surgery have been demonstrated to facilitate the identification of numerous tumor types and result in increased rates of complete resection and overall survival. METHODS: A review of the literature was performed, and data regarding the mechanism of the fluorescence agents, their administration, and intraoperative tumor visualization were extracted. Both in vitro and in vivo studies were assessed. The application of these agents to pituitary tumors, their advantages and limitations, as well as future directions are presented here. RESULTS: Numerous laboratory and clinical studies have described the use of 5-ALA, fluorescein, indocyanine green, and OTL38 in pituitary lesions. All of these drugs have been demonstrated to accumulate in tumor cells. Several studies have reported the successful use of the majority of the agents in inducing intraoperative tumor fluorescence. However, their sensitivity and specificity varies across the literature and between functioning and non-functioning adenomas. CONCLUSIONS: At present, numerous studies have shown the feasibility and safety of these agents for pituitary adenomas. However, further research is needed to assess the applicability of fluorescence-guided surgery across different tumor subtypes as well as explore the relationship between their use and postoperative clinical outcomes.

Guidelines in the management of CNS tumors.

INTRODUCTION: Evidence-based, clinical practice guidelines in the management of central nervous system tumors (CNS) continue to be developed and updated through the work of the Joint Section on Tumors of the Congress of Neurological Surgeons (CNS) and the American Association of Neurological Surgeons (AANS). METHODS: The guidelines are created using the most current and clinically relevant evidence using systematic methodologies, which classify available data and provide recommendations for clinical practice. CONCLUSION: This update summarizes the Tumor Section Guidelines developed over the last five years for non-functioning pituitary adenomas, low grade gliomas, vestibular schwannomas, and metastatic brain tumors.

Proposed definition of competencies for surgical neuro-oncology training.

OBJECTIVE: The aim of this work is to define competencies and entrustable professional activities (EPAs) to be imparted within the framework of surgical neuro-oncological residency and fellowship training as well as the education of medical students. Improved and specific training in surgical neuro-oncology promotes neuro-oncological expertise, quality of surgical neuro-oncological treatment and may also contribute to further development of neuro-oncological techniques and treatment protocols. Specific curricula for a surgical neuro-oncologic education have not yet been established. METHODS: We used a consensus-building approach to propose skills, competencies and EPAs to be imparted within the framework of surgical neuro-oncological training. We developed competencies and EPAs suitable for training in surgical neuro-oncology. RESULT: In total, 70 competencies and 8 EPAs for training in surgical neuro-oncology were proposed. EPAs were defined for the management of the deteriorating patient, the management of patients with the diagnosis of a brain tumour, tumour-based resections, function-based surgical resections of brain tumours, the postoperative management of patients, the collaboration as a member of an interdisciplinary and/or -professional team and finally for the care of palliative and dying patients and their families. CONCLUSIONS AND RELEVANCE: The present work should subsequently initiate a discussion about the proposed competencies and EPAs and, together with the following discussion, contribute to the creation of new training concepts in surgical neuro-oncology.

Neurosurgical management of brain and spine tumors in the COVID-19 era: an institutional experience from the epicenter of the pandemic.

The challenges of neurosurgical patient management and surgical decision-making during the 2019-2020 COVID-19 worldwide pandemic are immense and never-before-seen in our generation of neurosurgeons. In this case-based formatted report, we present the Mount Sinai Hospital (New York, NY) Department of Neurosurgery institutional experience in the epicenter of the pandemic and the guiding principles for our current management of intracranial, skull base, and spine tumors. The detailed explanations of our surgical reasoning for each tumor case is tailored to assist neurosurgeons across the United States as they face these complex operative decisions put forth by the realities of the pandemic.

Postoperative outcomes following glioblastoma resection using a robot-assisted digital surgical exoscope: a case series.

INTRODUCTION: Maximal extent of resection (EOR) of glioblastoma (GBM) is associated with greater progression free survival (PFS) and improved patient outcomes. Recently, a novel surgical system has been developed that includes a 2D, robotically-controlled exoscope and brain tractography display. The purpose of this study was to assess outcomes in a series of patients with GBM undergoing resections using this surgical exoscope. METHODS: A retrospective review was conducted for robotic exoscope assisted GBM resections between 2017 and 2019. EOR was computed from volumetric analyses of pre- and post-operative MRIs. Demographics, pathology/MGMT status, imaging, treatment, and outcomes data were collected. The relationship between these perioperative variables and discharge disposition as well as progression-free survival (PFS) was explored. RESULTS: A total of 26 patients with GBM (median age = 57 years) met inclusion criteria, comprising a total of 28 cases. Of these, 22 (79%) tumors were in eloquent regions, most commonly in the frontal lobe (14 cases, 50%). The median pre- and post-operative volumes were 24.0 cc and 1.3 cc, respectively. The median extent of resection for the cohort was 94.8%, with 86% achieving 6-month PFS. The most common neurological complication was a motor deficit followed by sensory loss, while 8 patients (29%) were symptom-free. CONCLUSIONS: The robotic exoscope is safe and effective for patients undergoing GBM surgery, with a majority achieving large-volume resections. These patients experienced complication profiles similar to those undergoing treatment with the traditional microscope. Further studies are needed to assess direct comparisons between exoscope and microscope-assisted GBM resection.

Hyperthermia treatment advances for brain tumors.

Hyperthermia therapy (HT) of cancer is a well-known treatment approach. With the advent of new technologies, HT approaches are now important for the treatment of brain tumors. We review current clinical applications of HT in neuro-oncology and ongoing preclinical research aiming to advance HT approaches to clinical practice. Laser interstitial thermal therapy (LITT) is currently the most widely utilized thermal ablation approach in clinical practice mainly for the treatment of recurrent or deep-seated tumors in the brain. Magnetic hyperthermia therapy (MHT), which relies on the use of magnetic nanoparticles (MNPs) and alternating magnetic fields (AMFs), is a new quite promising HT treatment approach for brain tumors. Initial MHT clinical studies in combination with fractionated radiation therapy (RT) in patients have been completed in Europe with encouraging results. Another combination treatment with HT that warrants further investigation is immunotherapy. HT approaches for brain tumors will continue to a play an important role in neuro-oncology.