Brain Tumor Resection Research Articles

RAGE Inhibitors as Alternatives to Dexamethasone for Managing Cerebral Edema Following Brain Tumor Surgery.

Resection of brain tumors frequently causes injury to the surrounding brain tissue that exacerbates cerebral edema by activating an inflammatory cascade. Although corticosteroids are often utilized peri-operatively to alleviate the symptoms associated with brain edema, they increase operative morbidities and suppress the efficacy of immunotherapy. Thus, novel approaches to minimize cerebral edema caused by neurosurgical procedures will have significant utility in the management of patients with brain tumors.We have studied the role of the receptor for advanced glycation end products (RAGE) and its ligands on inflammatory responses to neurosurgical injury in mice and humans. Blood-brain barrier (BBB) integrity and neuroinflammation were characterized by Nanostring, flow cytometry, qPCR, and immunoblotting of WT and RAGE knockout mice brains subjected to surgical brain injury (SBI). Human tumor tissue and fluid collected from the resection cavity of patients undergoing craniotomy were also analyzed by single-cell RNA sequencing and ELISA.Genetic ablation of RAGE significantly abrogated neuroinflammation and BBB disruption in the murine SBI model. The inflammatory responses to SBI were associated with infiltration of S100A9-expressing myeloid-derived cells into the brain. Local release of pro-inflammatory S100A9 was confirmed in patients following tumor resection. RAGE and S100A9 inhibitors were as effective as dexamethasone in attenuating neuroinflammation. However, unlike dexamethasone and S100A9 inhibitor, RAGE inhibition did not diminish the efficacy of anti-PD-1 immunotherapy in glioma-bearing mice. These observations confirm the role of the RAGE axis in surgically induced neuroinflammation and provide an alternative therapeutic option to dexamethasone in managing post-operative cerebral edema.

Association between insomnia disorder and mortality among patients who underwent craniotomy for brain tumor resection: a South Korean nationwide cohort study.

To assess the prevalence and related factors of a newly developed insomnia disorder following craniotomy for brain tumor resection. Furthermore, we examined the association of pre- and postoperative insomnia with the 2-year mortality rate. The South Korean national registration cohort database was used as the data source. This study includes all adult patients who underwent craniotomy for brain tumor resection from January 1, 2011, to December 31, 2017. G47.0 and F51.0 (International Statistical Classification of Diseases and Related Health Problems 10th Revision codes) were used to identify insomnia disorders. In total, 4,851 patients were included. Among them, 913 (18.8%) and 447 (9.2%) patients were assigned to the preoperative and postoperative insomnia groups, respectively. After modeling using multivariable logistic regression, older age (odds ratio (OR) 1.02, 95% confidence interval (CI) 1.01-1.03; P < 0.001), reoperation within 1year (OR 2.12, 95% CI 1.47-3.06; P < 0.001), and newly acquired brain disability (OR 1.32, 95% CI 1.01-1.71; P = 0.043) were associated with an increased prevalence of newly developed postoperative insomnia disorder. After modeling using multivariable Cox regression, the preoperative and postoperative insomnia disorder groups showed a 1.17-fold (hazard ratio (HR) 1.17, 95% CI 1.02-1.34; P = 0.021) and a 1.85-fold (HR 1.85, 95% CI 1.59-2.15, P < 0.001) increased 2-year all-cause mortality risk compared to the control group, respectively. In South Korea, 9.2% of the patients with brain tumors were newly diagnosed with an insomnia disorder following craniotomy for brain tumor resection, which was associated with an increased risk of 2-year mortality.

Same-day discharge after brain tumor resection: a prospective pilot study.

PurposeOutpatient brain surgery has many advantages for the psychological and physical wellbeing of patients, as well as reduced costs to the health care system. Compared with inpatient admissions, same day discharges reduce patient exposure to nosocomial infection, thromboembolic complications, and medical error. We aim to establish a prospectively collected quality outcomes database to examine the outcomes of patients that undergo brain tumor resection and are discharged home the same day as surgery.MethodsWe have established a prospectively collected quality outcomes database to examine the outcomes of all patients that underwent brain tumor resection by a single neurosurgeon (R.J.K) at our institution from August 2020 to August 2021 and were discharged home the same day as surgery.ResultsOver the one-year period this study was conducted, 37 of 334 patients met inclusion criteria for the outpatient protocol. Thirty-two patients were discharged on the same day as surgery. Five patients (14%) were considered eligible for outpatient surgery but were ultimately admitted to the hospital postoperatively and were discharged after an overnight observation. No postoperative complications were noted at two-week postoperative follow-up.ConclusionIn select patients undergoing brain tumor surgery, same day discharge should be considered. Establishing a multidisciplinary team of physicians, nurses, radiologists, and physical therapists is critical to achieving this aim. Physicians should have a low threshold to admit a patient with concerning exam findings, complications, or complicated past medical history. Once discharged, open communication with the patient and their family is critical to detect complications that should trigger rehospitalization and intervention.

Effect of Artificial Intelligence Tutoring vs Expert Instruction on Learning Simulated Surgical Skills Among Medical Students

To better understand the emerging role of artificial intelligence (AI) in surgical training, efficacy of AI tutoring systems, such as the Virtual Operative Assistant (VOA), must be tested and compared with conventional approaches. To determine how VOA and remote expert instruction compare in learners' skill acquisition, affective, and cognitive outcomes during surgical simulation training. This instructor-blinded randomized clinical trial included medical students (undergraduate years 0-2) from 4 institutions in Canada during a single simulation training at McGill Neurosurgical Simulation and Artificial Intelligence Learning Centre, Montreal, Canada. Cross-sectional data were collected from January to April 2021. Analysis was conducted based on intention-to-treat. Data were analyzed from April to June 2021. The interventions included 5 feedback sessions, 5 minutes each, during a single 75-minute training, including 5 practice sessions followed by 1 realistic virtual reality brain tumor resection. The 3 intervention arms included 2 treatment groups, AI audiovisual metric-based feedback (VOA group) and synchronous verbal scripted debriefing and instruction from a remote expert (instructor group), and a control group that received no feedback. The coprimary outcomes were change in procedural performance, quantified as Expertise Score by a validated assessment algorithm (Intelligent Continuous Expertise Monitoring System [ICEMS]; range, -1.00 to 1.00) for each practice resection, and learning and retention, measured from performance in realistic resections by ICEMS and blinded Objective Structured Assessment of Technical Skills (OSATS; range 1-7). Secondary outcomes included strength of emotions before, during, and after the intervention and cognitive load after intervention, measured in self-reports. A total of 70 medical students (41 [59%] women and 29 [41%] men; mean [SD] age, 21.8 [2.3] years) from 4 institutions were randomized, including 23 students in the VOA group, 24 students in the instructor group, and 23 students in the control group. All participants were included in the final analysis. ICEMS assessed 350 practice resections, and ICEMS and OSATS evaluated 70 realistic resections. VOA significantly improved practice Expertise Scores by 0.66 (95% CI, 0.55 to 0.77) points compared with the instructor group and by 0.65 (95% CI, 0.54 to 0.77) points compared with the control group (P < .001). Realistic Expertise Scores were significantly higher for the VOA group compared with instructor (mean difference, 0.53 [95% CI, 0.40 to 0.67] points; P < .001) and control (mean difference. 0.49 [95% CI, 0.34 to 0.61] points; P < .001) groups. Mean global OSATS ratings were not statistically significant among the VOA (4.63 [95% CI, 4.06 to 5.20] points), instructor (4.40 [95% CI, 3.88-4.91] points), and control (3.86 [95% CI, 3.44 to 4.27] points) groups. However, on the OSATS subscores, VOA significantly enhanced the mean OSATS overall subscore compared with the control group (mean difference, 1.04 [95% CI, 0.13 to 1.96] points; P = .02), whereas expert instruction significantly improved OSATS subscores for instrument handling vs control (mean difference, 1.18 [95% CI, 0.22 to 2.14]; P = .01). No significant differences in cognitive load, positive activating, and negative emotions were found. In this randomized clinical trial, VOA feedback demonstrated superior performance outcome and skill transfer, with equivalent OSATS ratings and cognitive and emotional responses compared with remote expert instruction, indicating advantages for its use in simulation training. ClinicalTrials.gov Identifier: NCT04700384.

Application of Intraoperative Contrast-Enhanced Ultrasound in the Resection of Brain Tumors.

To investigate the value of routine intraoperative ultrasound (IU) and intraoperative contrast-enhanced ultrasound (ICEUS) in the surgical treatment of brain tumors, and to explore the utilization of ICEUS for the removal of the remnants surrounding the resection cavity. In total, 51 patients who underwent operations from 2012 to 2018 due to different tumors in the brain were included in this study. The clinical data were evaluated retrospectively. IU was performed in all patients, among which 28 patients underwent ICEUS. The effects of IU and ICEUS on tumor resection and recurrence were evaluated. Semiquantitative analysis was performed to compare ICEUS parameters of the brain tumor with those of the surrounding tissue. In total, 36 male and 15 female patients were included in this study. The average age was 43 years (range: 14-68 years). The follow-up period was from 7 to 74 months (mean follow-up 32 months). IU was used in all patients, and no lesion was missed. Among them, 28 patients underwent ICEUS. The rate of total removal of the ICEUS group (23/28, 82%) was significantly higher than that of the IU group (11/23, 48%) (P<0.05). The recurrence rate of ICEUS and IU was 18% (5/23), and 22% (5/28), respectively, and the difference did not reach statistical significance (P>0.05). The semiquantitative analysis showed that the intensity and the transit time of microbubbles reaching the lesions were significantly different from the intensity and the transit time of microbubbles reaching the surrounding tissue (P<0.05) and reflected indirectly the volume and the speed of blood perfusion in the lesions was higher than those in the surrounding tissue. ICEUS is a useful tool in localizing and outlining brain lesions, especially for the resection of the hypervascular lesions in the brain. ICEUS could be more beneficial for identifying the remnants and improving the rate of total removal of these lesions than routine intraoperative ultrasound.

Label-free identification of human glioma xenograft of mouse brain with quantitative ultraviolet photoacoustic histology imaging.

The ability to unveil molecular specificities of endogenous nonfluorescent chromophores of ultraviolet photoacoustic imaging technology enables label-free histology imaging of tissue specimens. In this work, we exploit ultraviolet photoacoustic microscopy for identifying human glioma xenograft of mouse brain ex vivo. Intrinsically excellent imaging contrast of cell nucleus at ultraviolet photoacoustic illumination along with good spatial resolution allows for discerning the brain glioma of freshly-harvested thick brain slices, which circumvents laborious time-consuming preparations of the tissue specimens including micrometer-thick slicing and H&E staining that are prerequisites in standard histology analysis. The identification of tumor margins and quantitative analysis of tumor areas is implemented, representing good agreement with the standard H&E-stained observations. Quantitative ultraviolet photoacoustic microscopy can access fast pathological assessment to the brain tissues, and thus potentially facilitates intraoperative brain tumor resection to precisely remove all cancerous cells and preserve healthy tissue for maintaining its essential function.

Comparative associations of baseline frailty status and age with postoperative mortality and duration of hospital stay following metastatic brain tumor resection.

Metastatic brain tumors are the most common intracranial neoplasms diagnosed in the United States. Although baseline frailty status has been validated as a robust predictor of morbidity and mortality across various surgical disciplines, evidence within cranial neurosurgical oncology is limited. Adult metastatic brain tumor patients treated with resection were identified in the National Inpatient Sample during the period of 2015-2018. Frailty was quantified using the 11-point modified frailty index (mFI-11) and its association with clinical endpoints was evaluated through complex samples multivariable logistic regression and receiver operating characteristic (ROC) curve analyses. Among 13,650 metastatic brain tumor patients identified (mean age 62.8years), 26.8% (n = 3665) were robust (mFI = 0), 31.4% (n = 4660) were pre-frail (mFI = 1), 23.2% (n = 3165) were frail (mFI = 2), and 15.8% (n = 2160) were severely frail (mFI ≥ 3). On univariable assessment, these cohorts stratified by increasing frailty were significantly associated with postoperative complications (13.6%, 15.9%, 23.9%, 26.4%; p < 0.001), mortality (1.2%, 1.4%, 2.7%, 3.2%; p = 0.028), and extended length of stay (eLOS) (15.7%, 22.5%, 28.9%, 37.7%; p < 0.001). Following multivariable logistic regression analysis, frailty (by mFI-11) was independently associated with postoperative mortality (aOR 1.34, 95% CI 1.08, 1.65) and eLOS (aOR 1.26, 95% CI 1.17, 1.37), while increasing age was not associated with these endpoints. ROC curve analysis demonstrated superior discrimination of frailty (by mFI-11) in comparison with age for both mortality (AUC 0.61 vs. 0.58) and eLOS (AUC 0.61 vs. 0.53). Further statistical assessment through propensity score adjustment and decision tree analysis confirmed and extended the findings of the primary analytical models. Frailty may be a more robust predictor of postoperative outcomes in comparison with age following metastatic brain tumor resection.

Combined Neurophysiotherapy and Accelerated Skill Acquisition Programme in Improving Upper Extremity Motor Function in Hemiplegia after Brain Tumour Resection

Astrocytomas are one of the most common primary tumours of central nervous system seen in paediatric population. Although it is treatable and has a good prognosis, some individuals suffer from motor dysfunction following brain tumour resection which could result in decreased mobility, difficulty with daily tasks, increased risk of immobility-related problems, falls, pain, anxiety/depression. Thus, having a negative impact on overall quality of life and functional independence. Comprehensive neurophysiotherapy in such cases play a critical role in preventing and alleviating motor dysfunction, and its effects, and improve functional independence. This is the report of a 10-year-old female with astrocytoma in the right frontoparietal lobe, which was diagnosed using magnetic resonance imaging and immunohistochemistry. She underwent craniotomy for the same. But after tumour resection, she developed left hemiplegia wherein involvement of upper limb was more as compared to lower limb. She was given neurophysiotherapy and Accelerated Skill Acquisition Programme (ASAP) which aided in improving upper extremity motor function and functional independence.

Assessment of safe and gross total resection of intra-axial brain tumors

Background Safe and gross total resection (GTR) of intra-axial brain-tumor surgery is associated with improving functional outcomes, reducing symptoms, and decreasing the incidence of postoperative complications. Intraoperative imaging helps in achieving the maximum extent of resection. Intraoperative evaluation of the neurological function provides safe tumor resection in eloquent areas. Aim This study aimed to assess the achievement of GTR of intra-axial brain tumors guided by neuronavigation and intraoperative ultrasound and to evaluate the safety of tumor resection in eloquent areas with the use of intraoperative neurophysiological monitoring or awake craniotomy. Patients and methods This study included 30 patients with intra-axial brain tumors in the period from September 2019 to February 2021. Neuronavigation and intraoperative ultrasound were used for all cases, while intraoperative neurophysiological monitoring or awake craniotomy was used for intra-axial brain tumor in eloquent area. Operative details, outcomes, and final results had been recorded and analyzed. Results The mean age was 42 years (4–75 years). GTR was achieved in 18/30 (60%) of all cases. GTR was achieved in 4/10 (40%) of tumors located in the eloquent area, while GTR increased to 14/20 (70%) in noneloquent areas. The mean Karnofsky performance status for all cases has improved from 80 preoperatively to 86.67 postoperatively. Conclusion Neuronavigation and intraoperative ultrasound provides maximization of the extent of resection of intra-axial brain tumors. Intraoperative neurophysiological monitoring or awake craniotomy provides safe tumor resection in eloquent areas.

Awake craniotomy with dexmedetomidine during resection of brain tumours located in eloquent regions.

An awake craniotomy (AC) is the gold standard for the resection of supra-tentorial brain tumours in eloquent areas. Intraoperative monitoring "on-demand" of essential eloquent brain functions and the increasing need to preserve higher intellectual functions during surgery requires aunique anaesthetic approach during AC. Dexmedetomidine is considered the first-choice pharmacological agent for sedation during AC. Twenty-six patients with asingle brain tumour located in areas of eloquent brain function were enrolled in this prospective study. The patients underwent AC under conscious sedation. Motor-evoked potentials and brainstem-evoked auditory potentials were measured using neurophysiological tests during surgery to assess brain potentials. Intraoperative brain relaxation was reached using amodified Bristow scale. Neuromonitoring and psychological tests were maintained until meningeal closure. All operations were carried out successfully, and no reoperations were needed. No significant impact on circulatory and respiratory parameters was observed during conscious sedation based on dexmedetomidine. Neither instrumental airway support nor conversion to general anaesthesia was necessary. Brain relaxation was good in 84% of cases. Intraoperative epileptic episodes were observed in 15% of the patients. Neuro-logical and psychological monitoring was satisfactory. Unaltered muscle force was observed postoperatively in 88% of the patients. AC performed under conscious sedation, and dexmedetomidine infusion without instrumental airway support, was safe and well-tolerated by patients with comfortable physiological sleep for most of the procedure. This approach to AC was associated with minimal risk of perioperative adverse events and may be particularly beneficial in patients with severe comorbidities.

Fluorescein-guided resection of newly diagnosed high-grade glioma: Impact on extent of resection and outcome

IntroductionMaximal resection of high-grade glioma (HGG) improves progression–free survival (PFS) and overall survival (OS). Fluorescein sodium (FL) in combination with the YELLOW 560 ​nm filter (Carl Zeiss Meditec, Germany) is a safe and feasible method of visualizing residual tumor tissue during brain tumor resection. Research questionWe hypothesized that use of FL positively influenced the volumetric extent of resection (EOR), PFS, and OS in patients undergoing resection of a newly diagnosed HGG. Materials and methodUsing a prospective HGG registry, we identified 347 patients (median age 62.4 years; 141 women) with preoperative high-quality magnetic resonance images for volumetric analysis. Resection was performed under white light in n ​= ​151 (43.5%, white-light group) and under FL-guidance in n ​= ​196 (56.5%, FL group). Sex, age, presurgical Karnofsky Performance Index (KPI), O6-Methylguanin-DNA-Methyltransferase-Gene (MGMT) status, and adjuvant treatment modalities were well balanced between the groups. Volumetric analysis was performed by quantifying pre- and postoperative tumor volume based on gadolinium-enhanced T1 sequences in a blinded fashion. ResultsIn the FL group, postoperative tumor volume was significantly smaller (p ​= ​0.003); accordingly, quantitative EOR was significantly larger (p ​= ​0.003). Significantly more complete resections were achieved in the FL group than in the white-light group (p ​= ​0.003). The FL group showed significantly longer PFS (p ​= ​0.020) and OS (p ​= ​0.015, log rank testing). Multivariate Cox regression modelling showed age, presurgical KPI, MGMT status, and FL-guided resection to be independent prognostic factors for survival. Discussion and conclusionCompared to white-light resection, FL-guided resection of newly diagnosed HGG significantly improved EOR and prolonged OS.

Presurgical predictors of early cognitive outcome after brain tumor resection in glioma patients

Gliomas are commonly characterized by neurocognitive deficits that strongly impact patients’ and caregivers’ quality of life. Surgical resection is the mainstay of therapy, and it can also cause cognitive impairment. An important clinical problem is whether patients who undergo surgery will show post-surgical cognitive impairment above and beyond that present before surgery. The relevant rognostic factors are largely unknown.This study aims to quantify the cognitive impairment in glioma patients 1-week after surgery and to compare different pre-surgical information (i.e., cognitive performance, tumor volume, grading, and lesion topography) towards predicting early post-surgical cognitive outcome.We retrospectively recruited a sample of N = 47 patients affected by high-grade and low-grade glioma undergoing brain surgery for tumor resection. Cognitive performance was assessed before and immediately after (∼1 week) surgery with an extensive neurocognitive battery. Multivariate linear regression models highlighted the combination of predictors that best explained post-surgical cognitive impairment.The impact of surgery on cognitive functioning was relatively small (i.e., 85% of test scores across the whole sample indicated no decline), and pre-operative cognitive performance was the main predictor of early post-surgical cognitive outcome above and beyond information from tumor topography and volume. In fact, structural lesion information did not significantly improve the accuracy of prediction made from cognitive data before surgery.Our findings suggest that post-surgery neurocognitive deficits are only partially explained by preoperative brain damage. The present results suggest the possibility to make reliable, individualized, and clinically relevant predictions from relatively easy-to-obtain information.

Rapid intraoperative diagnosis of pediatric brain tumors using Raman spectroscopy: A machine learning approach

BackgroundSurgical resection is a mainstay in the treatment of pediatric brain tumors to achieve tissue diagnosis and tumor debulking. While maximal safe resection of tumors is desired, it can be challenging to differentiate normal brain from neoplastic tissue using only microscopic visualization, intraoperative navigation, and tactile feedback. Here, we investigate the potential for Raman spectroscopy (RS) to accurately diagnose pediatric brain tumors intraoperatively.MethodsUsing a rapid acquisition RS device, we intraoperatively imaged fresh ex vivo brain tissue samples from 29 pediatric patients at the Lucile Packard Children’s Hospital between October 2018 and March 2020 in a prospective fashion. Small tissue samples measuring 2-4 mm per dimension were obtained with each individual tissue sample undergoing multiple unique Raman spectra acquisitions. All tissue samples from which Raman spectra were acquired underwent individual histopathology review. A labeled dataset of 678 unique Raman spectra gathered from 160 samples was then used to develop a machine learning model capable of (1) differentiating normal brain from tumor tissue and (2) normal brain from low-grade glioma (LGG) tissue.ResultsTrained logistic regression model classifiers were developed using our labeled dataset. Model performance was evaluated using leave-one-patient-out cross-validation. The area under the curve (AUC) of the receiver-operating characteristic (ROC) curve for our tumor vs normal brain model was 0.94. The AUC of the ROC curve for LGG vs normal brain was 0.91.ConclusionsOur work suggests that RS can be used to develop a machine learning-based classifier to differentiate tumor vs non-tumor tissue during resection of pediatric brain tumors.

The default network is causally linked to creative thinking

Creative thinking represents a major evolutionary mechanism that greatly contributed to the rapid advancement of the human species. The ability to produce novel and useful ideas, or original thinking, is thought to correlate well with unexpected, synchronous activation of several large-scale, dispersed cortical networks, such as the default network (DN). Despite a vast amount of correlative evidence, a causal link between default network and creativity has yet to be demonstrated. Surgeries for resection of brain tumors that lie in proximity to speech related areas are performed while the patient is awake to map the exposed cortical surface for language functions. Such operations provide a unique opportunity to explore human behavior while disrupting a focal cortical area via focal electrical stimulation. We used a novel paradigm of individualized direct cortical stimulation to examine the association between creative thinking and the DN. Preoperative resting-state fMRI was used to map the DN in individual patients. A cortical area identified as a DN node (study) or outside the DN (controls) was stimulated while the participants performed an alternate-uses-task (AUT). This task measures divergent thinking through the number and originality of different uses provided for an everyday object. Baseline AUT performance in the operating room was positively correlated with DN integrity. Direct cortical stimulation at the DN node resulted in decreased ability to produce alternate uses, but not in the originality of uses produced. Stimulation in areas that when used as network seed regions produced a network similar to the canonical DN was associated with reduction of creative fluency. Stimulation of areas that did not produce a default-like network (controls) did not alter creative thinking. This is the first study to causally link the DN and creative thinking.

Development of a Navigation-guided Fence-post Catheter for Brain Tumor Resection.

Navigation system devices have been developed to allow precise resection of brain tumor. The fence-post catheter techniques that use a navigation system have been used in many neurosurgery centers. However, an exclusive catheter for the fence-post catheter techniques have not been made, and substituted silicon tube of the cerebral ventricle drainage or a Nelaton catheter is widely used. In this brief technical note, we describe a new fence-post catheter with steel tip device that was designed for more precise tissue resection and is useful in tumor resection. The newly designed fence-post catheter helps to visually gauge the accurate depth from the tumor bottom during tumor resection. Furthermore, the catheter tip has moderate weight and is made of a non-magnetic material. Using our fence-post catheter, which has a metal part at the tip of the tube (length, 13 mm), operators can clearly notice that they are getting closer to base of the tumor by checking the metal part during the resection of deep tumors. Our newly developed fence-post tube enables easy confirmation of the distance to deep-tissue regions and improves the degree of safety during tumor removal. J. Med. Invest. 69 : 117-119, February, 2022.

Second-look surgery after pediatric brain tumor resection – Single center analysis of morbidity and volumetric efficacy

IntroductionPostoperative residual tumor can occur for intentional or unintentional reasons. Decision-making regarding second-look surgery has to weigh molecular biology, probability of total resection and prognostic relevance against potential additional morbidity. In interdisciplinary tumor boards the neurosurgeon has to estimate risk and efficacy of second-look surgery in individual cases, based on precise data. Research questionAim of this study was to provide such data by analyzing morbidity and volumetric efficacy of second-look surgery at a designated pediatric neuro-oncology unit. Material and methodsChildren who received second-look surgery in 2007–2018 after incomplete resections were analyzed retrospectively. Measurements were performed on early postoperative magnetic resonance imaging, comparing axial diameter-based measurement as well as computer-assisted volumetric analysis. Results59 patients (37% of the overall cohort; 21 female; mean age: 8 ​± ​5 years) received a subtotal (n ​= ​35) or near total (n ​= ​24) resection. After interdisciplinary case review, 12 of these patients received second-look surgery mainly for residual ependymoma. This led to further tumor volume reduction in all cases (new degrees of resection: subtotal ​= ​2, near total ​= ​6, gross total ​= ​4). No new permanent morbidity or perioperative mortality was observed. Discussion and conclusionSecond-look surgery did not increase mortality and permanent morbidity, had an 8% rate of transient morbidity and achieved tumor volume reduction above 95% in 75% of selected cases, with 4 additional gross total resections. Second-look surgery is safe and effective with regard to volumetric outcome parameters even in cases with good initial resections, although the role of second-look surgery regarding oncological outcome has to be further investigated in times of personalized molecular medicine.

A case of improved walking endurance after brain tumor resection due to exercise therapy focusing on hip adductor muscle action in the loading-response phase

A case of improved walking endurance after brain tumor resection due to exercise therapy focusing on hip adductor muscle action in the loading-response phase

Using machine learning to evaluate large-scale brain networks in patients with brain tumors: Traditional and non-traditional eloquent areas.

BackgroundLarge-scale brain networks and higher cognitive functions are frequently altered in neuro-oncology patients, but comprehensive non-invasive brain mapping is difficult to achieve in the clinical setting. The objective of our study is to evaluate traditional and non-traditional eloquent areas in brain tumor patients using a machine-learning platform.MethodsWe retrospectively included patients who underwent surgery for brain tumor resection at our Institution. Preoperative MRI with T1-weighted and DTI sequences were uploaded into the Quicktome platform. We categorized the integrity of nine large-scale brain networks: language, sensorimotor, visual, ventral attention, central executive, default mode, dorsal attention, salience and limbic. Network integrity was correlated with preoperative clinical data.ResultsOne-hundred patients were included in the study. The most affected network was the central executive network (49%), followed by the default mode network (43%) and dorsal attention network (32%). Patients with preoperative deficits showed a significantly higher number of altered networks before the surgery (3.42 vs 2.19, P < .001), compared to patients without deficits. Furthermore, we found that patients without neurologic deficits had an average 2.19 networks affected and 1.51 networks at-risk, with most of them being related to non-traditional eloquent areas (P < .001).ConclusionOur results show that large-scale brain networks are frequently affected in patients with brain tumors, even when presenting without evident neurologic deficits. In our study, the most commonly affected brain networks were related to non-traditional eloquent areas. Integrating non-invasive brain mapping machine-learning techniques into the clinical setting may help elucidate how to preserve higher-order cognitive functions associated with those networks.

Emerging Super-specialty of Neurology: Intraoperative Neurophysiological Monitoring (IONM) and Experience in Various Neurosurgeries at a Tertiary Care Hospital in Doha, Qatar.

IntroductionIntraoperative neurophysiological monitoring (IONM) helps in better patient outcomes by minimizing risks related to the functional status of the nervous system during surgical procedures. An IONM alert to the surgical team during the surgery can help them identify the cause and take immediate corrective action. IONM confers possible benefits, including improved surgical morbidity and mortality, better patient care, minimal neurological deficits, reduced hospital stay, medical costs, and litigation risk. In addition, a highly skilled IONM team will make a better patient outcome.MethodsWe retrospectively reviewed 62 consecutive patients who underwent intracranial and spinal neurosurgical procedures. Multimodality IONM was utilized, including somatosensory evoked potentials, transcranial electrical motor evoked potential, spontaneous and triggered electromyography, electroencephalography, electrocorticography, cortical sensory mapping, and direct electrical cortical stimulation. Of a total of 62 patients, two patients revealed neurotonic EMG discharges during IONM, and most patients woke up without any new neurological deficit.ResultsSixty-two patients were included, ranging from age 5 to 77 years (mean 43.5 years), with 54.8% men and 45.2% female. Multimodality IONM was used in all patients. Two EMG alerts were recorded during IONM, during a brain tumor resection, and right acetabular hip surgery with postoperative right foot drop.ConclusionMultimodality IONM is the gold standard of care for any surgical services and is used as real-time monitoring of functional integrity of neural structures at risk. If utilized by trained and expert teams, numerous surgeries may benefit from multimodality intraoperative neurophysiologic monitoring.

TB-9 An attempt to establish a patient-derived brain tumor culture model by organoid culture method

Background: Molecular heterogeneity among and within tumors are one of the reasons for the poor survival rate of brain tumors even with the current standard therapy. However, monolayer culture and neuro-sphere culture (NS) use exogenous growth factors, so may not show the true nature of the tumor. And the culture establishment rate is low, especially low-grade tumors. Therefore, we used the glioblastoma organoid (GBO) culture method showed by Fadi to create culture models of various brain tumors and investigated their characteristics. Methods: We examined the establishment rate in pathological and genotypic types of 56 patients who underwent brain tumor resection at our hospital between January 2020 and June 2021 and were cultured with GBO or NS. If tumor cells are increased visually at 1 month after culture, we defined establishment. Results: There were 15 cases of glioblastoma, 7 cases of anaplastic astrocytoma, 7 cases of diffuse astrocytoma, 3 cases of diffuse midline glioma, 2 cases of anaplastic oligodendroglioma, 5 cases of oligodendroglioma, and 16 cases of others. The establishment rate was 76.5% by the GBO method and 40% by the N S method. By histological type, GBO: 80% in glioblastoma, NS: 58.3% in glioblastoma, GBO: 83.3% in AA, NS: 40% in AA, and GBO: 100% in DA. The IDH mutation and pTERT mutation were investigated in GBO: IDHwt/TERT+ 87.5%, IDHwt/TERT- 64.3%, IDHmt/TERT- 100%, and in NS: IDHwt/TERT+ 75%, IDHwt/TERT- 33.3%, IDHmt/ TERT- 20% in NS. In addition, establishment was observed in GBO 2 case in medulloblastoma, 1 case in ependymoma. Discussion and Conclusion: This suggest that GBO can be used to establish culture models for low-grade tumors. In addition, GBO can establish culture earlier, so it is expected to be applicable to personalized therapies such as preclinical drug efficacy studies tailored to individual patients.