Search

Low-income countries (LICs) and lower-middle-income countries (LMICs) are presented with unique challenges and opportunities when performing awake craniotomy (AC) for brain tumors. These circumstances arise from factors that are financial, infrastructural, educational, personnel, and sociocultural in nature. We performed a systematic narrative review of series on AC for intra-axial brain tumors in LICs/LMICs using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, focusing on the challenges and opportunities in these settings. The PubMed, Scopus, and Web of Science databases were searched. After initially identifying 74 studies, inclusion-exclusion criteria were applied, leaving a total of 14 studies included in the review. These involved 409 patients who underwent AC in LICs/LMICs. These series were from India, Ghana, Nigeria, Iran, Pakistan, Morocco, the Philippines, and Egypt. The most common pathology encountered were gliomas (10–70%). Most studies (11/14, 78.5%) reported on their technique of cortical-subcortical mapping. All reported on motor mapping and 8 of these performed language mapping. The most common outcomes reported were seizure and neurologic deficits, and longest follow-up was at 1 year. Challenges noted were lack of equipment and trained personnel, need for validated tests for the local setting, and sociocultural factors. Opportunities identified were volume for training, technique innovation, and international collaboration. There are numerous challenges and opportunities that arise when performing AC in LICs/LMICs. A collaborative approach toward harnessing the opportunities, and seeking creative solutions to address the challenges, would provide an ideal mechanism toward advancing neurosurgical care and specialty worldwide. [ABSTRACT FROM AUTHOR]

Sir William Macewen, a Scottish surgeon, made significant contributions to neurosurgery, beginning with his successful brain tumor resection in 1879. Born in 1848, Macewen's upbringing in a maritime family fostered a practical approach to learning. Macewen's pivotal brain tumor surgery demonstrated his adherence to antiseptic practices and precise localization techniques. Controversy arose regarding his precedence in neurosurgery, which he addressed through meticulous documentation and public presentations. His diagnostic prowess extended to cases of cerebral abscesses and intracranial conditions, relying on clinical observations rather than imaging technology. His 1893 monograph on brain infections remains influential in neurosurgery. Beyond neurosurgery, Macewen was innovative in asepsis, hernia repair, and bone surgery. His legacy as a clinical educator and advocate for surgical advancements earned him widespread recognition. This historical review aimed to explore and evaluate the published literature regarding Macewen's early brain tumor surgeries, seeking to establish his precedence over later surgeons including Godlee and Bennett. [ABSTRACT FROM AUTHOR]

A lack of brain expansion is considered a risk factor for recurrence after evacuation of a chronic subdural hematoma (CSDH). To the best of our knowledge, no studies have reported on objective measurement of brain expansion after evacuation of a CSDH. We performed a retrospective analysis of prospectively collected data of patients undergoing 2 burr hole evacuation of a CSDH. We measured the depth of the brain surface from the frontal burr hole dural opening after hematoma evacuation using a specially devised measuring tool. Other predictors analyzed for recurrence of hematoma were age, gender, a history of hypertension, the use of anticoagulant and/or antiplatelet agents, Glasgow coma scale score at presentation, unilateral or bilateral hematoma, computed tomography appearance, and hematoma thickness. Among 88 patients who underwent hematoma evacuation, 3 (3.4%) underwent surgery for recurrence. The significant factors associated with recurrence were the presence of bilateral hematoma (P = 0.001), hematoma width >2.3 cm (P = 0.04), gradation type of hematoma on the computed tomography scan (P = 0.03), and the depth of the brain after hematoma evacuation (P = 0.02). The brain expanded less in those with recurrence, with a mean depth of the brain of 18 ± 6 mm versus 7.27 ± 7.8 mm in those without recurrence. Evacuation of a CSDH through 2 burr holes, along with copious irrigation and bed rest for 3 days, resulted in a very low recurrence rate without the use of a drain. A lack of brain expansion might be a predictor of recurrence. To the best of our knowledge, this is the first study to quantitatively measure the depth of the brain at surgery in patients undergoing surgery for CSDH. [ABSTRACT FROM AUTHOR]

Despite the growing acceptance of neuronavigation in the field of neurosurgery, there is limited comparative research with contradictory results. This study aimed to compare the effectiveness (tumor resection rate and survival) and safety (frequency of neurological complications) of surgery for brain gliomas with or without neuronavigation. This retrospective cohort study evaluated data obtained from electronic records of patients who underwent surgery for gliomas at Dr. Alejandro Dávila Bolaños Military Hospital and the Clinic Hospital of Barcelona between July 2016 and September 2022. The preoperative and postoperative clinical and radiologic characteristics were analyzed and compared according to the use of neuronavigation. This study included 110 patients, of whom 79 underwent surgery with neuronavigation. Neuronavigation increased gross total resection by 57% in patients in whom it was used; gross total resection was performed in 56% of patients who underwent surgery with neuronavigation as compared with 35.5% in those who underwent surgery without neuronavigation (risk ratio [RR], 1.57; P = 0.056). The incidence of postoperative neurologic deficits (transient and permanent) decreased by 79% with the use of neuronavigation, (12% vs. 33.3%; RR, 0.21; P = 0.0003). Neuronavigation improved survival in patients with grade IV gliomas (15 months vs. 13.8 months), but it was not statistically significant (odds ratio (OR), 0.19; P = 0.13). Neuronavigation improved the effectiveness (greater gross total resection of tumors) and safety (fewer neurological deficits) of brain glioma surgery. However, neuronavigation does not significantly influence the survival of patients with grade IV gliomas. [ABSTRACT FROM AUTHOR]

Surgical site infections after craniotomy (SSI-CRANs) are a serious adverse event given the proximity of the wound to the central nervous system. SSI-CRANs are associated with substantial patient morbidity and mortality. Despite the importance and recognition of this event in other surgical fields, there is a paucity of evidence in the neurosurgical literature devoted to SSI-CRAN specifically in patients after brain tumor surgery. Systematic searches of Medline, Embase, and Cochrane Central were undertaken. The primary outcome was the incidence of SSI-CRAN at 30 and 90 days. Secondary outcomes were risk factors for SSI-CRAN. Thirty-seven studies reporting 91,907 patients with brain tumors who underwent cranial surgery were included in the meta-analysis. Pooled incidence of SSI-CRAN at 30 and 90 days was 4.03% (95% CI: 2.94%–5.28%, I2 = 97.3) and 6.17% (95% CI: 3.16%–10.07%, I2 = 97.3), respectively. Specifically, incidence of SSI-CRAN following surgery for posterior fossa tumors was the highest at 9.67% (95% CI: 5.98%–14.09%, I2 = 75.5). Overall pooled incidence of readmission within 30 days and reoperation due to SSI-CRAN were 13.9% (95% CI: 12.5%–15.5%, I2 = 0.0) and 16.3% (95% CI: 5.4%–31.3%, I2 = 72.9), respectively. Risk factors for SSI-CRAN included reintervention (risk ratio [RR] 1.58, 95% CI: 1.22–2.04, I2 = 0.0), previous radiotherapy (RR 1.69, 95% CI: 1.20–2.38, I2 = 0.0), longer duration of operation (mean difference 64.18, 95% CI: 3.96–124.40 minutes, I2 = 90.3) and cerebrospinal fluid (CSF) leaks (RR 14.26, 95% CI: 2.14–94.90, I2 = 73.2). SSI-CRAN affects up to 1 in 14 patients with brain tumors. High-risk groups include those with reintervention, previous radiotherapy, longer duration of operation, and CSF leaks. Further prospective studies should focus on bundles of care that will reduce SSI-CRAN. [ABSTRACT FROM AUTHOR]

Although the linear scalp incision is commonly used in neurosurgical practice, a systematic study elucidating its pros and cons in a specific surgical setting is lacking. Herein, we analyzed our experience with linear scalp incision in brain tumor surgery and the impact on intraoperative variables and postoperative complications. Patients undergoing brain tumor surgery (January 2014−December 2021) at 2 neurosurgical departments were included and divided into 2 groups: linear or flap scalp incision. Patients' demographics characteristics, surgical variables, and wound-related complications were analyzed. More than a total of 1036 craniotomies, linear incision (mean length 6cm) was adopted in 282 procedures (27.2%). Mean maximum diameter of the craniotomy was 5.25 cm, with no statistical difference between the 2 groups. In emergency surgery (36 cases), the linear and flap incisions were used indifferently. Linear incision was predominant in supratentorial and suboccipital lesions. Flap incision was significantly more frequent among meningiomas (P < 0.01). Neuronavigation, operative microscope, and subgaleal drain were more frequently used in the flap scalp incision group (P = 0.01). Overall complication rate was comparable to flap scalp opening (P = 0.40). The use of the linear incision was broadly applied for the removal of supratentorial and suboccipital tumors granting adequate surgical exposure with a low rate of postoperative complications. Tumors skull base localization resulted the only factor hindering the use of the linear incision. The choice of 1 incision over another didn't show to have any impact on intraoperative and postoperative variables, and it remains mainly based on surgeon expertise/preference. [ABSTRACT FROM AUTHOR]

Eloquent brain tumor surgery involves the delicate task of resecting tumors located in regions of the brain responsible for critical functions, such as language, motor control, and sensory perception. Preserving these functions is of paramount importance to maintain the patient's quality of life. Corticocortical evoked potentials (CCEPs) have emerged as a valuable intraoperative monitoring technique that aids in identifying and preserving eloquent cortical areas during surgery. This systematic review aimed to assess the utility of CCEPs in eloquent brain tumor surgery and determine their effectiveness in improving patient outcomes. A comprehensive literature search was conducted using electronic databases, including PubMed/Medline and Scopus. The search strategy identified 11 relevant articles for detailed analysis. The findings of the included studies consistently demonstrated the potential of CCEPs in guiding surgical decision making, minimizing the risk of postoperative neurological deficits, and mapping functional connectivity during surgery. However, further research and standardization are needed to fully establish the clinical benefits and refine the implementation of CCEPs in routine neurosurgical practice. [ABSTRACT FROM AUTHOR]

Awake craniotomy is a unique method to prevent motor deficits during the resection of lesions located in or close to functional areas. We sought to study the outcomes of pediatric craniotomy on published studies. The search for articles was performed through multiple search engines: PubMed, Google Scholar, Web of Science, and Wiley. The following search terms were used for screening the titles and abstracts: "awake brain surgery" and "children" or "pediatrics," "awake craniotomy," and "children" or "pediatrics," "pediatrics awake craniotomy," "awake brain surgery pediatrics," and "tumors." On initial screening of the titles and abstracts, 54 articles were found. After a thorough review of the full texts of obtained articles and removing duplicates, 16 articles remained. The mean age group was 12.23 years. There was a slight difference between genders who underwent awake craniotomy in the pediatric age group, 52.7% male and 47.3% for female. Tumor resection was the most common indication of the surgery. Almost half (47.9%) experienced complete recovery following the surgery. However, of those who had complicated recovery, 7.5% experienced a speech deficit. This systematic review summarized that awake brain surgery can prevent significant motor and language deficits postoperatively in children after tumor resection as it is considered a feasible and safe procedure. [ABSTRACT FROM AUTHOR]

Mesoamerica is culturally rich in diverse aspects, such as nature, sociology, and archeology. Several neurosurgical techniques were described during the Pre-Hispanic era. In Mexico, various cultures, such as the Aztec, Mixtec, Zapotec, Mayan, Tlatilcan, and Tarahumara, developed surgical procedures using different tools to perform cranial and probably brain interventions. Trepanations, trephines, and craniectomies are different concepts utilized to describe skull operations, which were conducted to treat traumatic, neurodegenerative, and neuropsychiatric diseases, and as a prominent form of ritual practice. More than 40 skulls have been rescued and studied in this region. In addition to written medical sources, archeological vestiges allow a more profound comprehension of Pre-Columbian brain surgery. The purpose of this study is to present the existing evidence of cranial surgery in Pre-Hispanic Mexican civilizations and their worldwide counterparts, procedures that have contributed to the global neurosurgical armamentarium, and have significantly impacted the medical practice's evolution. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) surgery for Parkinson's Disease (PD) has become more and more popular in Vietnam. However, the accuracy of implantation and affecting factors are under investigation. The objective of this study is to evaluate the accuracy of the subthalamic nucleus (STN)-DBS electrode implantation technique for treatment PD at Nguyen Tri Phuong Hospital and University Medical Center. To investigate factors related to accuracy. We carried out a retrospective analysis of 58 patients with advanced PD who underwent STN-DBS surgery at Nguyen Tri Phuong Hospital and University Medical Center in Ho Chi Minh City, Viet Nam between June 2014 and July 2021 (115 leads total). All patients underwent the procedure with standard frame-based techniques under local anesthesia with microelectrode recording and macrostimuation test. Twenty-six female (44.8%) and thirty-two male (55.2%) patients with a mean age of 60.4 ± 8.3 years old (40-76 years) were included. Of total of 115 electrodes implanted, the mean target error (ΔT), radial error (ΔR), angle error (Δθ) were 1.94 ± 0.73 mm; 1.16 ± 0.69 mm; 2.22 ± 4.24 degrees, respectively. Vector error on each coordinate axis ΔX, ΔY, ΔZ were −0.35 ± 1.02 mm, +0.99 ± 0.82 mm, +0.73 ± 0.99 mm, respectively. There was a statistically significant correlation between subdural air volume, cortical shift, intracranial electrode bending, and accuracy. The current STN-DBS electrode implantation technique applied in our centers was quite accurate with acceptable error. More clinical trials are necessary to directly compare affecting factors to the accuracy of electrode implantation. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established and effective neurosurgical treatment for relieving motor symptoms in Parkinson disease. The localization of key brain structures is critical to the success of DBS surgery. However, in clinical practice, this process is heavily dependent on the radiologist's experience. In this study, we propose an automatic localization method of key structures for STN-DBS surgery via prior-enhanced multi-object magnetic resonance imaging segmentation. We use the U-Net architecture for the multi-object segmentation, including STN, red nucleus, brain sulci, gyri, and ventricles. To address the challenge that only half of the brain sulci and gyri locate in the upper area, potentially causing interference in the lower area, we perform region of interest detection and ensemble joint processing to enhance the segmentation performance of brain sulci and gyri. We evaluate the segmentation accuracy by comparing our method with other state-of-the-art machine learning segmentation methods. The experimental results show that our approach outperforms state-of-the-art methods in terms of segmentation performance. Moreover, our method provides effective visualization of key brain structures from a clinical application perspective and can reduce the segmentation time compared with manual delineation. Our proposed method uses deep learning to achieve accurate segmentation of the key structures more quickly than and with comparable accuracy to human manual segmentation. Our method has the potential to improve the efficiency of surgical planning for STN-DBS. [ABSTRACT FROM AUTHOR]

Recent advances in intraoperative neuronavigation and cranial access devices have facilitated an increasing interest in the use of minimally invasive techniques (minimally invasive surgery) to safely treat subcortical lesions via a parafascicular approach. Newly developed expandable retractors, such as the MindsEye system further optimize such approaches. In this technical report, we describe the nuances in minimally invasive surgery parenchymal hematoma evacuation using the MindsEye device. After placement of the device, the inner stylet and inner obturator are removed, and the expandable sheath is left in place and secured into place with a Greenberg refractor. The sheath easily dilates to the surgeonss preference with a dial, and the walls of the sheath are composed of a thin, clear, membrane to allow easy visualization of the lesion. We additionally retrospectively reviewed clinical characteristics and outcomes across three patients treated at our facility with spontaneous multicompartment intracranial hematoma using the MindsEye system. We provide a video case demonstrating the use of the MindsEye retractor in a transfrontal parenchymal hematoma evacuation. Successful evacuation with achieved in less than 90 minutes with near total clot removal and resolution of mass effect for all reviewed cases with no patients experiencing procedure-related postoperative decline. Minimally invasive catheter-based and parafascicular approaches using tubular retractors are increasingly recognized as a viable option in the treatment of subcortical lesions. The MindsEye is the first expandable brain access port designed for removal of deep intracranial lesions. We believe it represents a recent addition in the armament of cranial surgeons. [ABSTRACT FROM AUTHOR]

Nationwide databases show that iatrogenic stroke and postoperative hematoma are among the commonest complications in brain tumor surgery, with a 10-year incidence of 16.3/1000 and 10.3/1000, respectively. However, techniques for handling severe intraoperative hemorrhage and dissecting, preserving, or selectively obliterating vessels traversing the tumor are sparse in the literature. Records of the senior author's intraoperative techniques during severe haemorrhage and vessel preservation were reviewed and analyzed. Intraoperative media demonstrations of key techniques were collected and edited. In parallel, a literature search investigating technique description in handling severe intraoperative hemorrhage and vessel preservation in tumor surgery was undertaken. Histologic, anesthetic, and pharmacologic prerequisites of significant hemorrhagic complications and hemostasis were analyzed. The senior author's techniques for arterial and venous skeletonization, temporary clipping with cognitive or motor mapping, and ION monitoring were categorized. Vessels interfacing with tumor are labeled intraoperatively as supplying/draining the tumor, or traversing en passant, while supplying/draining functional neural tissue. Intraoperative techniques of differentiation were analyzed and illustrated. Literature search found 2 vascular-related complication domains in tumor surgery: perioperative management of excessively vascular intraparenchymal tumors and lack of intraoperative techniques and decision processes for dissecting and preserving vessels interfacing or traversing tumors. Literature searches showed a dearth of complication-avoidance techniques in tumor-related iatrogenic stroke, despite its high prevalence. A detailed preoperative and intraoperative decision process was provided along with a series of case illustrations and intraoperative videos showing the techniques required to reduce intraoperative stroke and associated morbidity addressing a void in complication avoidance of tumor surgery. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging (HSI) has the potential to enhance surgical tissue detection and diagnostics. Definite utilization of intraoperative HSI guidance demands validated machine learning and public datasets that currently do not exist. Moreover, current imaging conventions are dispersed, and evidence-based paradigms for neurosurgical HSI have not been declared. We presented the rationale and a detailed clinical paradigm for establishing microneurosurgical HSI guidance. In addition, a systematic literature review was conducted to summarize the current indications and performance of neurosurgical HSI systems, with an emphasis on machine learning-based methods. The published data comprised a few case series or case reports aiming to classify tissues during glioma operations. For a multitissue classification problem, the highest overall accuracy of 80% was obtained using deep learning. Our HSI system was capable of intraoperative data acquisition and visualization with minimal disturbance to glioma surgery. In a limited number of publications, neurosurgical HSI has demonstrated unique capabilities in contrast to the established imaging techniques. Multidisciplinary work is required to establish communicable HSI standards and clinical impact. Our HSI paradigm endorses systematic intraoperative HSI data collection, which aims to facilitate the related standards, medical device regulations, and value-based medical imaging systems. [ABSTRACT FROM AUTHOR]

The prognostic value of preoperative glycated hemoglobin (HbA1c) testing is controversial. The available evidence on the role of preoperative HbA1c in predicting postoperative complications after different surgical procedures has been conflicting. The primary aim of our retrospective observational cohort study was to assess the association between preoperative HbA1c and postoperative infections after elective craniotomy. We extracted and analyzed data from an internal hospital database on 4564 patients who underwent neurosurgical intervention from January 2017 to May 2022. The primary outcome measure of the present study was infections established in the first week after surgery using the Centers for Disease Control and Prevention criteria. The records were stratified by the HbA1c values and intervention types. For patients who had undergone brain tumor removal with a preoperative HbA1c ≥6.5%, the odds of early postoperative infections were increased (odds ratio, 2.08; 95% confidence interval, 1.16–3.72; P = 0.01). We found no association between HbA1c and early postoperative infections for patients who had undergone elective cerebrovascular intervention, cranioplasty, or a minimally invasive procedure. After adjusting for age and gender, the threshold for significant infection risk for neuro-oncological patients increased with an HbA1c ≥7.5% (adjusted odds ratio, 2.97; 95% confidence interval, 1.37–6.45; P = 0.0058). For patients undergoing elective intracranial surgery for brain tumor removal, a preoperative HbA1c ≥7.5% is associated with a higher infection rate within the first postoperative week. Future prospective studies are required to assess the prognostic value of this association for clinical decision-making. [ABSTRACT FROM AUTHOR]

Bibliometric analyses of the scientific literature have grown increasingly popular in the past few decades. However, patent bibliometric studies, evaluation of technological literature, have not yet been applied in neurosurgery. To perform a pilot patent bibliometric analysis of the top 100 most cited patents in cranial neurosurgery. The Lens was used to query multiple databases, to select the top 100 cranial neurosurgical patents based upon forward patent citations. These were organized into 9 categories based on technological descriptors and were evaluated based on the earliest priority date, year issued, and expiration status, among others. The top 100 most cited patents included technology underlying 3D navigation (n = 31), pharmacology and implants (n = 20), vascular occlusion (n = 5), craniotomy closure (n = 9), focal lesioning and tissue resection (n = 8), brain and systemic cooling (n = 5), neuroendoscopy (n = 8), neuromonitoring and stimulation (6), and technologies improving surgeon performance (n = 8). Ninety-six patents were filed in the United States, 72 were expired, 19 are still active, and 9 were listed as inactive. The highest number of patents was applied for from the mid-1990s to the mid-2000s. Demonstrated trends showed no meaningful correlation between patent rank and earliest priority date (linear trendline y = 0.7107 x −1367.5; R2 = 0.0671), while a very strong correlation was found between patent rank and citations per year (power trendline y = 127.93 x −1.094; R2 = 0.8579). Patent bibliometrics allow evaluation of neurosurgical advancements from the past and enable subsequent development of cutting-edge technology in the future. The described method is a reproducible and reliable technique for evaluating our field's patent literature. [ABSTRACT FROM AUTHOR]

Intraoperative ultrasound (iUS) is a well-established technique whose aim is to provide real-time visualization of deep lesions during brain surgery. The lack of definition of anatomic semeiotics and the unusual direction of the insonation plane make interpretation and orientation challenging for the surgeon who newly approaches to such a tool. We propose a novel protocol to be applied during the surgical planning for intracranial lesions surgery, a so-called ultrasound-oriented surgical planning ("UOSP") protocol, and we provide a retrospective analysis of 21 patients who underwent surgery for an intracranial lesion in which UOSP was applied. To further enlighten different surgical orientation strategies and possible limitations given by the technique, we discuss 3 illustrative cases assigned to 3 categories ("basic," "intermediate," and "challenging" lesions) with progressively growing difficulty in anatomic orientation during a surgical procedure. A total of 21 patients operated between March 2021 and July 2021 and where the UOSP protocol was applied during surgical planning were evaluated retrospectively. The UOSP protocol was performed the days before the surgical intervention by the same surgical team. The UOSP protocol was successfully applied in all 21 patients. In all cases, the preoperative imaging obtained during surgical planning corresponded to the images observed during the application of iUS. The introduction of the UOSP protocol during the planification of the surgical intervention for an intracerebral lesion may serve as a key factor to overcome the actual limitations inherent to the iUS technique. Utilization of this protocol may facilitate wider use of iUS in neurosurgery. [ABSTRACT FROM AUTHOR]

Mispositioning of microelectrodes during deep brain stimulation surgery can incur serious complications for patients. Current practice of creating a burr hole for introduction of the microelectrode is done freehand and can cause trajectory misalignment. We aimed to create a sterilizable surgical adjunct to minimize error from burr hole placement. We designed and demonstrated clinical use of a 3D-printed surgical jig that can be mounted to the current Cosman-Roberts-Wells stereotactic frame. The jig allowed accurate placement of the perforating burr for creation of the burr hole. Intraoperative usage of the jig in 11 patients who underwent bilateral deep brain stimulation microelectrode placement for Parkinson disease demonstrated high accuracy of microelectrode placement, with an average 1.18 mm deviation (range, 0–2.7 mm) from intended trajectories. No intraoperative complications were encountered. This proof-of-concept study highlights the utility of 3D-printed surgical adjuncts that are fully customizable and rapidly produced to improve current surgical practice. The jig reduced surgery duration, need for multiple trajectories, and risk of potentially devastating neurological complications. As demonstrated, 3D-printed devices are useful as surgical adjuncts to optimize safety and efficacy in deep brain stimulation surgeries. [ABSTRACT FROM AUTHOR]

Cranioplasty with synthetic implant can be performed to restore function and form of the skull after resection of malignancy infiltrating the bone. The aim of this study was to examine the rate of implant failure and tumor recurrence in patients undergoing nonautologous cranioplasty and tumor resection. In this retrospective single-center study, 48 patients were identified who had undergone cranioplasty with synthetic implants after tumor resection between 2010 and 2020. The medical records were analyzed to investigate patient demographics, surgery data, cranioplasty failure rates, and rate of tumor recurrence. Cranioplasty failed in 8 patients. The median time to implant failure was 220 days with most failures occurring within 1 year (5 of 8). There was no significant difference in rate or time to failure between the different cranioplasty materials (P = 0.39). Low body mass index (P < 0.05), previous craniectomy/cranioplasty (P < 0.05), previous radiation therapy to the brain/skull (P < 0.05), and skin closure with sutures (P < 0.05) were associated with an increased risk of implant failure. Tumors recurred in 15 patients. Cranioplasty surgery with synthetic implants carries a relatively high risk of failure, regardless of type of cranioplasty material used. Skin closure with staples may be beneficial in these patients. [ABSTRACT FROM AUTHOR]

Frailty refers to a state of weakness that can arise due to age or illnesses, and frailty predisposes individuals to several adverse health outcomes. This has been postulated to prognosticate the outcome of various surgeries, including surgeries for primary brain tumors; however, no meta-analysis has validated this finding. We conducted a systematic review and meta-analysis to investigate the prognostic utility of frailty for the outcome of primary brain tumor surgery. We performed a systematic search of the PubMed, EMBASE, and SCOPUS databases for studies investigating the ability of frailty to predict the outcome of primary brain tumor surgery. Meta-analysis of the information provided in the thirteen studies that made up our sample. Hospital length of stay (effect size 0.94; 95% confidence interval [CI]: 0.37, 1.51; p: 0.00), postoperative complications (effect size 10.31; 95% CI: −5.88, 26.86; p: 0.21), readmission (effect size 0.82; 95% CI: 0.23, 1.41; p: 0.01), nonroutine discharge (effect size 1.07; 95% CI: 0.48, 1.65; 0.00), postoperative mortality (effect size 1.48; 95% CI: 0.81, 2.02; p: 0.00), and overall survival (effect size 1.53; 95% CI: 0.29, 2.76; p: 0.02). This study showed little correlation with postoperative mortality, readmission, nonroutine discharge, length of hospital stay, or overall survival, and fragility had less significance in these areas but showed no statistical significance in predicting postoperative complications following surgery for primary brain tumors. [ABSTRACT FROM AUTHOR]

Brain shift may cause significant error in neuronavigation, leading the surgeon to possible mistakes. Intraoperative magnetic resonance imaging (MRI) is the most reliable technique in brain tumor surgery. Unfortunately, it is highly expensive and time consuming and, at the moment, it is available only in few neurosurgical centers. In this case series the surgical workflow for brain tumor surgery is described where neuronavigation of preoperative MRI, intraoperative computed tomography (CT) scan, and ultrasound (US) as well as rigid and elastic image fusion between preoperative MRI and intraoperative US and CT, respectively, was applied to 4 brain tumor patients in order to compensate for surgically induced brain shift by using a commercially available software (Elements Image Fusion 4.0 with Virtual iMRI Cranial; Brainlab AG, München, Germany). Four illustrative cases demonstrated successful integration of different components of the described intraoperative surgical workflow. The data indicate that intraoperative navigation update is feasible by applying intraoperative 3-dimensional US and CT scanning as well as rigid and elastic image fusion applied depending on the degree of observed brain shift. Integration of multiple intraoperative imaging techniques combined with rigid and elastic image fusion of preoperative MRI may reduce the risk of incorrect neuronavigation during brain tumor resection. Further studies are needed to confirm the present findings in a larger population. [ABSTRACT FROM AUTHOR]

Advanced therapies in neurosurgery, such as deep brain stimulation (DBS), would benefit from improved patient education materials. Three-dimensional (3D) printed anatomical models represent a recent development for improving patient education for neurosurgical procedures. In this study, 40 patients undergoing DBS surgery consultation were randomly assigned to 1 of 2 groups: an experimental group, which received a demonstration of DBS therapeutic neuroanatomical targets in a 3D printed brain model plus standard patient education (PE), or a control group, which received standard PE alone. Patients in the DBS model plus PE group showed a significant increase in patient confidence and understanding of the brain structures targeted during a DBS procedure compared with patients in the PE-only group (P < 0.01). There was no difference in perceived risk, comfort, or anxiety related to the procedure. In the first randomized controlled study to our knowledge of 3D printed models for DBS consultation, our results demonstrate that patients had improved understanding of their therapy with the models. However, the models alone did not affect risk evaluation or comfort with surgery. A 3D printed brain model may help improve patient understanding of DBS surgery. [ABSTRACT FROM AUTHOR]

Despite reports on the efficacy of checkpoint inhibitor (CPI) immunotherapies for metastatic cancers, there are limited data on the effectiveness of surgery for brain metastases (BMs) that have progressed after previous CPI treatment. We sought to evaluate surgical outcomes for patients undergoing BM resection after failing CPI immunotherapy. A single-center series of patients with BM that had progressed after previous CPI treatment and who underwent surgery was retrospectively reviewed. Outcomes of interest included local tumor progression, leptomeningeal dissemination, and overall survival. Cox proportional hazard models were applied to determine factors associated with outcomes of interest. Over a 16-year period, 26 patients underwent resection of 32 BMs at a median of 1.2 months (range, 2 days–41.1 months) from their last CPI dose. Median censored survival was 7.6 months from surgery and was shorter than the survival of patients without previous CPI exposure (21.9 months; log-rank P = 0.001). Four BMs had local central nervous system progression (16%), and 75% of procedures were associated with distant central nervous system progression within a median time of 3.3 months. Leptomeningeal disease developed after 33.3% of surgeries. Increased time from first BM diagnosis to surgery was associated with increased risk of leptomeningeal disease (hazard ratio by month, 1.07; 95% confidence interval, 1.01–1.14; P = 0.03). Patients who require BM resection after previous CPI treatment have a poor overall prognosis compared with patients without previous CPI exposure. Although local control rates are acceptable, these patients are at high risk for developing distant progression and leptomeningeal disease postoperatively. [ABSTRACT FROM AUTHOR]

Maximizing the patient's onco-functional balance is the central tenet of brain tumor surgery. Consequently, numerous surgical adjuncts have been developed to facilitate identification of the tumor–brain interface and preservation of functional anatomy. Among these, intraoperative neurophysiologic monitoring (IONM) with direct cortical stimulation (DCS) and subcortical stimulation (SCS) remains the gold standard for real-time, functional mapping of motor and language activity. Stimulation techniques are not standardized and vary significantly across institutions, however. This is particularly true with SCS for mapping motor function. We reviewed the state of subcortical IONM and mapping techniques, including historical and predicate literature as well as new and emerging techniques. Here we discuss their evolution, clinical utility, and limitations to direct future research and application. Our evaluation of the background and current clinical use of DCS and SCS techniques and protocols and identification of current trends and limitations focuses specifically on methods of SCS, given the heterogeneity in the published literature. We suggest directions to optimize the clinical utility of these tools. Despite significant heterogeneity in published techniques, trends support use of the Taniguchi method for SCS. Novel dynamic stimulation techniques may improve accuracy. Prospective studies to define standardized guidelines are needed. [ABSTRACT FROM AUTHOR]

The use of three-dimensional (3D) printing in neurosurgery has become more prominent in recent years for surgical training, preoperative planning, and patient education. Several smaller studies are available using 3D printing; however, there is a lack of a concise review. This article provides a systematic review of 3D models in use by neurosurgical residents, with emphasis on training, learning, and simulation. A structured literature search of PubMed and Embase was conducted using PRISMA guidelines to identify publications specific to 3D models trialed on neurosurgical residents. Criteria for eligibility included articles discussing only neurosurgery, 3D models in neurosurgery, and models specifically tested or trialed on residents. Overall, 40 articles were identified that met inclusion criteria. These studies encompassed different neurosurgical areas including aneurysm, spine, craniosynostosis, transsphenoidal, craniotomy, skull base, and tumor. Most articles were related to brain surgery. Of these studies, vascular surgery had the highest overall, with 13 of 40 articles, which include aneurysm clipping and other neurovascular surgeries. Twenty-two articles discussed cranial plus tumor surgeries, which included skull base, craniotomy, craniosynostosis, and transsphenoidal. Five studies were specific to spine surgery. Subjective outcome measures of neurosurgical residents were most commonly implemented, of which results were almost unanimously positive. 3D printing technology is rapidly expanding in health care and neurosurgery in particular. The technology is quickly improving, and several studies have shown the effectiveness of 3D printing for neurosurgical residency education and training. [ABSTRACT FROM AUTHOR]

To develop an asleep motor mapping paradigm for accurate detection of the corticospinal tract during glioma surgery and compare outcomes with awake patients undergoing glioma resection. A consecutive cohort of adult patients undergoing craniotomy for suspected diffuse glioma with tumor in a perirolandic location who had awake or asleep cortical and subcortical motor mapping with positive areas of motor stimulation were assessed for postoperative extent of resection (EOR), permanent neurological deficit, and proximity of stimulation to diffusion tensor imaging–based corticospinal tract depiction on preoperative magnetic resonance imaging. Outcome data were compared between asleep and awake groups. In the asleep group, all 16 patients had improved or no change in motor function at last follow-up (minimum 3 months of follow-up). In the awake group, all 23 patients had improved function or no change at last follow-up. EOR was greater in the asleep group (mean [SD] EOR 88.71% [17.56%]) versus the awake group (mean [SD] EOR 80.62% [24.44%]), although this difference was not statistically significant (P = 0.3802). Linear regression comparing distance from stimulation to corticospinal tract in asleep (n = 14) and awake (n = 4) patients was r = −0.3759, R 2 = 0.1413, P = 0.1853, and 95% confidence interval = −0.4453 to 0.09611 and r = 0.7326, R 2 = 0.5367, P = 0.2674, and 95% confidence interval = −7.042 to 14.75, respectively. In this small patient series, asleep motor mapping using commonly available motor evoked potential hardware appears to be safe and efficacious in regard to EOR and functional outcomes. [ABSTRACT FROM AUTHOR]

Background: Endoscopic procedures are useful in chronic subdural hematoma especially when there are septations, solid/organized hematoma, and the presence of bridging or neovessels in the cavity. Visualizing the distal hematoma cavity by a rigid scope is challenging in large and curved ones due to the hindrance by the brain surface. Combining rigid endoscopy and brain retractor can overcome this limitation., Methods: A retrospective study of 248 patients managed by endoscopic technique was performed and the relevant literature was reviewed., Results: The brain retractor was used in all patients. Average operative time, subgaleal drainage duration, and hospital stay were 56 minutes, 3.1 days, and 4.6 days, respectively. The average preoperative Glasgow coma scale (GCS) score was 12, which improved to 14 and 15 in 223 and 23 patients, respectively at discharge. There were solid clots, septations, bridging vessels, curved hematoma cavities, rapid expansion of the brain after partial hematoma removal, and recurrences in 59, 52, 15, 49, 19, and 2 patients, respectively. There were 2 deaths, without any procedure-related mortality., Conclusions: Endoscope was very effective and safe in the management of chronic subdural hematoma, especially in about 51% patients with solid clots, septations, and bridging vessels which could have been difficult to treat by conventional burr hole. It can avoid craniotomy in such patients. Good visualization and complete hematoma removal were possible with the help of an endoscope and brain retractor in about 27% of patients which could have been difficult with a rigid endoscope alone., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Visual field defects occasionally occur secondary to tumors in the parietal and the occipital lobes. The aim of this study was to analyze the efficacy of improvement in hemianopsia after surgery for metastatic brain tumors involving or adjacent to the optic radiation (OR). The study included 49 patients with brain metastasis in the parietal and occipital lobes in the present study. Preoperative and postoperative neurological assessments included visual field, Mini-Mental State Examination, and Karnofsky performance scale. Of 49 patients, 33 (67.3%) presented with preoperative homonymous hemianopsia. Of these 33 patients, the visual field was improved postoperatively in 17 patients (51.5%). In all patients regardless of preoperative hemianopsia, postoperative visual fields did not deteriorate. Tractography demonstrated that the OR was split by the tumor (n = 6) and fanning of fibers expanded along the lateral side of the tumor (n = 11). All tumors were removed via surgical access toward the medial side of the tumor. Gross total resection was achieved in most tumors in the group with visual improvement (n = 16/17; 94.1%). Improvement in the visual field was attributed to tumor location in the subcortical white matter, removal rate of the tumor, and higher postoperative Karnofsky performance scale score. The OR tended to deviate to the lateral side of the tumor in the parieto-occipital junction. The postoperative visual field improved even in cases of an occipital tumor. Based on the present study, total resection via an appropriate surgical route should be considered to preserve the OR, leading to improvement in the postoperative visual field. [ABSTRACT FROM AUTHOR]

Postoperative delirium is a common surgical complication that can be associated with poorer outcome. Many patients with brain tumors experience delirium after surgery. We hypothesize that patients who experience delirium after resection of a brain tumor will have worse outcomes post surgery in terms of mortality, disposition, and length of stay compared with those without postoperative delirium. We also examine differences between nurse and physician diagnoses of delirium. Data from patients undergoing brain tumor resection at University of Missouri Hospital were retrospectively collected. Delirium was defined using Diagnostic and Statistical Manual−5 criteria. Patients with delirium were compared with patients without delirium using chi-squared test, Cohen Kappa value, and binomial proportion analysis at 95% confidence intervals or P < 0.05. Of 500 patients having brain tumor resections, 93 (18.6%) were diagnosed with postoperative delirium. Patients with delirium had higher 30-day mortality (9.78% vs. 1.48%; P < 0.0001), required restraints more often (42.39% vs. 5.91%, P < 0.0001), had longer hospital length of stay (14.3 vs. 6.3 days; P < 0.0001), and increased skilled nursing facility disposition (57.3% vs. 26.11%; P < 0.0001) than patients without delirium. Diagnosis of delirium between nursing staff and clinicians moderately correlated (Kappa 0.5677 ± 0.0536). Delirium, a common postoperative complication after brain tumor surgery, is associated with longer length of stay, increased disposition to skilled nursing facility, and increased 30-day mortality. These findings reinforce the importance of early recognition, diagnosis, and treatment of postoperative delirium in brain tumor resection patients. [ABSTRACT FROM AUTHOR]

Hospital length of stay (LOS) is an important cost driver in neurosurgery. Broader surgical literature has shown that patient-related factors, including comorbidities, and procedure-related factors, such surgeon experience, may be associated with LOS. Because value optimization strategies may be targeted toward either domain, this study investigated the contributions of patient-related and procedure-related factors in predicting prolonged intensive care unit LOS (iLOS) and total hospital LOS (tLOS). Data for adult patients undergoing brain tumor surgery (2017–2019) were collected. Bivariate analyses for iLOS and tLOS were performed using the Mann-Whitney U test and Fisher exact test. Variables associated with either outcome with P < 0.10 were included in patient-only, procedure-only, and patient+procedure factor multivariate linear regression models. Model discrimination was quantified using C-statistics. Our 654 patients had a mean age of 57.54 years (standard deviation, ± 14.34 years). For iLOS, the patient-only model significantly outperformed the procedure-only model (P < 0.0001) and performed similarly to the patient+procedure model (P = 0.50). Other than tumor diagnosis, 5-Factor Modified Frailty Index score was the only factor associated with iLOS (P < 0.001) and tLOS (P < 0.001) on multivariate analysis. When predicting prolonged tLOS, the patient-only model significantly outperformed the procedure-only model (P < 0.0001), and performed similarly to patient+procedure models (P = 0.49). Patient-specific factors are the main drivers of prolonged iLOS and tLOS among patients with brain tumor. Frailty was significantly associated with both iLOS and tLOS on multivariate analysis. Efforts to improve care value should focus on strategies to optimize patient status, such as prehabilitation and enhanced recovery after surgery. [ABSTRACT FROM AUTHOR]

We investigated the role of a self-retaining retractor system, commonly used in ear, abdominal, vascular, urologic and gynecologic surgeries: the Lone Star retractor system. We report our experience in using the Lone Star retractor in different brain surgeries, at a single neurosurgical department. In 2019, patients who underwent brain surgery and in which the Lone Star Retractor System was used were considered for inclusion. Clinical and surgical data of included patients were prospectively collected. Postoperative VAS for local pain, and a properly designed intraoperative retractor stability score, were collected. Over 2019, the Lone Stare Retractor was used in 20 neurosurgical procedures: 9 high-grade glioma, 2 low-grade glioma, 4 cerebral metastases, and 5 meningiomas. Postoperative mean VAS score was 3.5 (range: 2–4). Intraoperative retractor stability score mean was 2 in frontal, 2 in pterional, 1.75 in subtemporal, 2 in interhemispheric, and 0.5 in suboccipital approaches. The Stony Brook Scar Evaluation Scale mean value was 4.4 (range: 3–5). In our institutional experience, the Lone Star retractor showed many advantages in different brain procedures, when compared with standard fishhooks and other retractors. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) use in health care has increased over the past few decades, with its utility expanding from a teaching tool to a highly reliable neuro-technology adjunct in multiple fields including neurosurgery. Generally, brain tumor surgery with the patient awake has only been performed for mapping of language and motor areas. With the rise of VR and advancing surgical techniques, neurosurgical teams are developing an increased understanding of patients' anatomo-functional connectivity. Consequently, more specific cognitive tasks are being required for the mapping and preservation of deeper layers of cognition. An extensive literature review was conducted with the inclusion criteria of manuscripts that described the use of VR during awake neurosurgery mapping. We identified 3 recent articles that met our inclusion criteria, yet none of them addressed the specific use of VR for cognition mapping. Consequently, a cognitive task phase was performed to search and craft the tasks and domains that better filled the spotted niche of this need inside the operating room. A proposed protocol was developed with 5 potential uses of VR for brain mapping during awake neurosurgery, each of them with a specific proposed example of use. The authors advocate for the use of a VR protocol as a feasible functional tool in awake-patient brain tumor surgery by using it as a complement during cognitive screening in addition to language testing. [ABSTRACT FROM AUTHOR]

The magnetic resonance imaging (MRI)-directed implantable guide tube technique allows for direct targeting of deep brain structures without microelectrode recording or intraoperative clinical assessment. This study describes a 10-year institutional experience of this technique including nuances that enable performance of surgery using readily available equipment. Eighty-seven patients underwent deep brain stimulation surgery using the guide tube technique for Parkinson disease (n = 59), essential tremor (n = 16), and dystonia (n = 12). Preoperative and intraoperative MRI was analyzed to measure lead accuracy, volume of pneumocephalus, and the ability to safely plan a trajectory for multiple electrode contacts. Mean target error was measured to be 0.7 mm (95% confidence interval [CI] 0.6–0.8 mm) in the anteroposterior plane, 0.6 mm (95% CI 0.5–0.7 mm) in the mediolateral plane, and 0.8 mm (95% CI 0.7–0.9 mm) in the superoinferior plane. Net deviation (Euclidean error) from the planned target was 1.3 mm (95% CI 1.2–1.4 mm). Mean intracranial air volume per lead was 0.2 mL (95% CI 0.1–0.4 mL). In total, 52 patients had no intracranial air on postoperative imaging. In all patients, a safe trajectory could be planned to target for multiple electrode contacts without violating critical neural structures, the lateral ventricle, sulci, or cerebral blood vessels. The MRI-directed implantable guide tube technique is a highly accurate, low-cost, reliable method for introducing deep brain electrodes. This technique reduces brain shift secondary to pneumocephalus and allows for whole trajectory planning of multiple electrode contacts. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is an important cause of trauma-related mortality and morbidity in Ethiopia. There are significant resource limitations along the entire continuum of care, and little is known about the neurosurgical activity and patient outcomes. All surgically treated TBI patients at the 4 teaching hospitals in Addis Ababa, Ethiopia were prospectively registered from October 2012 to December 2016. Data registration included surgical procedures, complications, reoperations, discharge outcomes, and mortality. A total of 1087 patients were included. The most common procedures were elevation of depressed skull fractures (49.5%) and craniotomies (47.9%). Epidural hematoma was the most frequent indication for a craniotomy (74.7%). Most (77.7%) patients were operated within 24 hours of admission. The median hospital stay for depressed skull fracture operations or craniotomies was 4 days. Decompressive craniectomy was only done in 10 patients. Postoperative complications were seen in 17% of patients, and only 3% were reoperated. Cerebrospinal fluid leak was the most common complication (7.9%). The overall mortality was 8.2%. Diagnosis, admission Glasgow Coma Scale (GCS) score, surgical procedure, and complications were significant predictors of discharge GCS score (P < 0.01). Age, admission GCS score, and length of hospital stay were significantly associated with mortality (P ≤ 0.005). The injury panorama, surgical activity, and outcome are significantly influenced by patient selection due to deficits within both prehospital and hospital care. Still, the neurosurgical services benefit a large number of patients in the greater Addis region and are qualitatively comparable with reports from high-income countries. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is a public health problem in Ethiopia. More knowledge about the epidemiology and neurosurgical management of TBI patients is needed to identify possible focus areas for quality improvement and preventive efforts. This prospective cross-sectional study (2012–2016) was performed at the 4 teaching hospitals in Addis Ababa, Ethiopia. All surgically treated TBI patients were included, and data on clinical presentation, injury types, and trauma causes were collected. We included 1087 patients (mean age 29 years; 8.7% females; 17.1% <18 years old). Only 15.5% of TBIs were classified as severe (Glasgow Coma Scale score 3–8). Depressed skull fracture (44.9%) and epidural hematoma (39%) were the most frequent injuries. Very few patients had polytrauma (3.1%). Assault was the most common injury mechanism (69.9%) followed by road traffic accidents (15.8%) and falls (8.1%). More than 80% of patients came from within 200 km of the hospitals, but the median time to admission was 24 hours. Most assault victims (80.4%) were injured >50 km from the hospitals, whereas 46% of road traffic accident victims came from the urban area. Delayed admission was associated with higher Glasgow Coma Scale scores and nonsevere TBI (P < 0.01). The injury panorama, delayed admission, and small number of operations performed for severe TBI are linked to a substantial patient selection bias both before and after hospital admission. Our results also suggest that there should be a geographical framework for tailored guidelines, preventive efforts, and development of prehospital and hospital services. [ABSTRACT FROM AUTHOR]

Perioperative craniotomy practices depend mainly on neurosurgeon preferences. To investigate the variations in these preferences, we surveyed neurosurgeons in Poland regarding different aspects of their practices. Anonymous questionnaires were circulated in 2019 at the neurosurgery conferences in Poland. We then analyzed the responses, categorized in subgroups by sex, affiliation, and stage of training. A total of 114 responses to the questionnaire were obtained. For surgical site exposure, regional hair shaving was the most common pattern (64.9%), followed by whole-scalp (19.3%) and strip line shaving (12.3%). Most respondents (65.8%) used clamp-based devices for bone flap fixation, and approximately one third (30.7%) reported using bone suturing. During cranioplasty, respondents most often used artificial bone implants (69.3%), followed by a preserved bone flap from the patient (24.5%). More than three quarters reported that they (77.2%) performed routine radiologic evaluation after uncomplicated brain tumor surgery. Most patients (64.0%) were discharged between the third and sixth postoperative days. Almost half of emergent surgeries (48.2%) and most elective surgeries (89.5%) were performed with the help of an assistant surgeon. No significant differences were found in practice between the sexes or by affiliation or training stage. We inferred an influence of regional economic status on some of the reported choices. Perioperative craniotomy practices among Polish neurosurgeons show a significant heterogeneity. Economic factors can explain some choices, but others trace to a conservative mindset. Further studies are needed to identify which factors are most relevant and to identify approaches to a standardized method of care. [ABSTRACT FROM AUTHOR]

Quality of life is essential for oncologic patients. Several tools are available to improve microsurgery and reduce morbidity. Diode laser is a precise and useful technology for microsurgery. The goal of this pioneer case series is to describe the oncologic use of the 980nm diode laser and the qualitative variables analyzed. Besides, review the current literature about lasers in neurosurgery. A longitudinal prospective study described patients with meningioma or glioma submitted to neurosurgical laser-assisted procedures. Also, we performed a review in medical databases using the terms "diode laser" and "neurosurgery." No paper described the use of a diode laser in neurooncology. The 980nm diode laser was used in 15 patients. The device is thin, silent, and easy to handle. Excellent hemostasis was observed, especially in skull base meningiomas. Also, it was easy and fast to delimit tumor from normal brain tissue without damage to surrounding parenchyma. No postoperative complications occurred. The diode laser is a useful tool for brain tumor surgery, particularly concerning hemostasis. Surgical site coagulation is effective without damage to adjacent structures, especially in gliomas near eloquent regions. We consider this technique a suitable adjuvant resource for brain tumor surgeries to provide an excellent hemostasis and help cut and vaporize a lesion. [ABSTRACT FROM AUTHOR]

The study of brain connectomics has led to a rapid evolution in the understanding of human brain function. Traditional localizationist theories are being replaced by more accurate network, or hodologic, approaches that model brain function as widespread processes dependent on cortical and subcortical structures, as well as the white matter tracts (WMTs) that link these areas. Recent surgical literature suggests that WMTs may be more critical to preserve than cortical structures because of the comparably lower capacity of recovery of the former when damaged. Given the relevance of eloquent WMTs to neurologic function and thus quality of life, neurosurgical interventions must be tailored to maximize their preservation. Direct electric stimulation remains a vital tool for identification and avoidance of these critical tracts. Neurosurgeons therefore require proper understanding of the anatomy and function of WMTs, as well as the reported contemporary tasks used during intraoperative stimulation. We review the relevant tracts involved in language, visuospatial, and motor networks and the updated direct electric stimulation–based mapping tasks that aid in their preservation. The dominant-hemisphere language WMTs have been mapped using picture naming, semantic association, word repetition, reading, and writing tasks. For monitoring of vision and spatial functions, the modified picture naming and line bisection tasks, as well as the recording of visual evoked potentials, have been used. Repetitive movements and monitoring of motor evoked potentials and involuntary movements have been applied for preservation of the motor networks. [ABSTRACT FROM AUTHOR]

Background: Intraoperative brain smear is an easy, rapid, and cost-effective technique for immediate diagnosis of brain tumors. Earlier studies have gauged its application on limited number of samples, but its diagnostic accuracy especially in low-resource settings, where its practice would be extremely helpful, is still undetermined. To investigate the diagnostic accuracy of intraoperative brain smear in resource-limited settings for diagnosis of brain tumors., Methods: A systematic search was conducted on PubMed, Google Scholar, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Embase for all articles utilizing intraoperative brain smears that were extracted. Studies from low- and middle-income countries (LMICs) with test performance characteristics were selected and subsequent values were summarized using a hierarchical summary receiver operating characteristic (ROC) curve via STATA and pooled using a random-effects model on MetaDiSc 2.0., Results: Twelve studies consisting of 1124 patients were identified. Six studies included both adult and pediatric population groups, while 4 investigated adults and 2 included pediatric patients. The pooled diagnostic odds ratio (OR) was calculated to be 212.52 (CI: [104.27-433.13]) of Bivariable pooled specificity and sensitivity were 92% (CI: [86%-96%]) and 96% (CI: [93%-98%]), respectively., Conclusions: Our study shows that intraoperative brain smear is not only an accurate and sensitive diagnostic modality in resource-rich settings, but it is also equally useful in resource-limited settings, making it an ideal method for rapid diagnosis., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Stereotactic brain biopsy is a crucial minimally invasive surgical technique leveraged to obtain tissue specimens from deep-seated intracranial lesions, offering a safer alternative to open craniotomy for patients who cannot tolerate the latter. Despite its effectiveness, the diagnostic yield varies across different centers and has not been widely studied in Sub-Saharan Africa., Methods: A single-center retrospective analysis was conducted on 67 consecutive stereotactic brain biopsy procedures carried out by experienced neurosurgeons between January 2012 and December 2022 at a tertiary center in Sub-Saharan Africa. Preoperative clinical status, biopsy type, postoperative complication rate, and histological diagnosis were meticulously analyzed. Factors associated with negative biopsy results were identified using IBM Statistical Package for the Social Sciences SPSS version for Mac, with Fisher exact test employed to detect differences in patient characteristics. Statistical significance was pegged at P < 0.05., Results: The overall diagnostic yield rate was 67%. Major contributors to negative biopsy outcomes were superficial location of the lesion, lesion size less than 10 cc, and the use of the Cape Town Stereotactic System. Enhanced yield rates of up to 93% were realized through the application of magnetic resonance imaging-based images, Stealth Station 7, and frozen section analysis. No correlation was observed between the number of cores obtained and the yield rate. Procedure complications were negligible, and no procedure-related mortality was recorded., Conclusions: The diagnostic yield rate from our study was somewhat lower than previously reported in contemporary literature, primarily attributed to the differing definitions of diagnostic yield, the dominant use of the older framed Cape Town Stereotactic System, computed tomography-based imaging, and the absence of intraoperative frozen section. Nevertheless, biopsies conducted using the frameless system were comparable with studies from other global regions. Our findings reaffirm that stereotactic brain biopsy when complemented with magnetic resonance imaging-based imaging, frameless stereotactic systems and intraoperative frozen section is a safe, effective, and reliable method for obtaining histological diagnosis., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The factors on which the accuracy of stereotactic brain biopsy depends are the competence of the neurosurgeon in obtaining a representative sample and the ability of the neuropathologist to make a histological diagnosis from a minuscule sample. Over the years intraoperative frozen section has enhanced the diagnostic yield of this minimally invasive procedure. Use of fluorescence in achieving a greater extent of resection is well-established in contemporary neurosurgical practice. This ability of brain tumors to take up the fluorescein sodium dye and glow under the YELLOW 560-nm filter has been utilized in a handful of studies to increase the diagnostic accuracy of stereotactic biopsy., Methods: We performed a prospective study where the fluorescein sodium dye was injected at a low dose and fluorescence of the biopsied core was compared with that of a tissue obtained from the normal parenchyma. Sample was labeled 'truly fluorescent' only when the glow was more than that of the tissue from normal parenchyma., Results: On cross-tabulating the index test (true fluorescence status) and the reference standard test (final histopathological report) the sensitivity of acquiring a representative sample was found to be 94.74%, specificity was 100%. The positive predictive value and negative predictive value were calculated to be 100% and 50% respectively. The diagnostic yield was comparable to that of the intraoperative frozen section., Conclusion: The use of the YELLOW 560-nm filter can make stereotactic biopsy faster, safer, less cumbersome, and more cost-effective, and can be used as a substitute for the frozen section in resource-constrained centers., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Three-dimensional (3D) printed models are used in the medical field. This study aimed to evaluate the feasibility and safety of a 3D-printed guide plate for use in brain biopsy., Methods: Twelve patients with intracranial lesions were retrospectively reviewed to determine clinical outcomes and technical procedural operability. These patients underwent brain biopsy assisted with the 3D-printed guide plate. Postoperative computed tomography was performed to assess the accuracy and associated complications of this guide plate., Results: All patients received definite diagnoses assisted by this guide plate. The deviations of the entry and target points were 3.93 ± 0.96 mm and 2.59 ± 0.11 mm, respectively. The angle drift of the puncture path was 5.12° ± 0.14°, and the deviation of the puncture depth was 2.35 ± 1.13 mm. The operation time ranged from 38.5 minutes with local anesthesia to 76.2 minutes with general anesthesia. No patient experienced complications., Conclusions: The 3D-printed guide plate was noninvasive and had acceptable accuracy and the flexibility of frameless systems. The economic and operative benefits of this device supported its status as a powerful tool for brain biopsy in medical facilities in economically disadvantaged areas or institutions without navigation systems., (Copyright © 2024 Elsevier Inc. All rights reserved.)

To evaluate the results of microsurgical clipping for single intracranial aneurysm (SIA) and multiple intracranial aneurysms (MIA) and compare the outcomes. All patients who underwent surgery for intracranial aneurysm (IA) at our institution over a 3-year period (June 2013 to May 2016) were included in this study. A total of 157 patients with 225 IAs were included. Forty-one of these patients had MIA (109 IAs, mean, 2.7 ± 1.2; range, 2–7), and remaining 116 had SIA. In the patients with MIA, all aneurysms were secured during the same admission whenever possible. Depending on the locations of the IAs and condition of brain during surgery (tense/lax), all aneurysms were secured on same day (in a single session, single or multiple craniotomy in 28 patients) or on different days (multiple sessions in 13 patients). Postoperative control angiography (DSA) before discharge could be done for 216 aneurysms (MIA, n = 105; SIA, n = 111). Successful occlusion of the aneurysm from circulation was noted in 96.2% (101/105) of MIA and 93.7% (104/111) of SIA. Follow-up of 6 months or longer was available for 146 patients. A modified Rankin Scale score ≤2 was considered a good outcome. Univariate analysis of the entire group revealed no significant difference in clinical outcomes between patients with SIA and MIA both at discharge (good outcome: MIA, 82.9%; SIA, 93.1%; P = 0.068) and at a final follow-up of ≥6 months (good outcome: MIA, 87.2%; SIA, 94.4%; P = 0.164). Clipping for MIA was not associated with poor outcome in multivariate analysis. Comparable clinical outcomes and high rates of complete aneurysm occlusion following microsurgical clipping can be expected in patients with SIA and patients with MIA. [ABSTRACT FROM AUTHOR]

Extent of resection (EOR) constitutes a crucial factor for patient prognosis in surgery of brain metastases (BMs). According to early studies using postoperative magnetic resonance imaging (MRI), an unexpected residual tumor was not uncommon. Knowledge of potential risk factors for incomplete BM resection would be of major importance to optimize surgical strategies. The aim of this study was to evaluate EOR in a large cohort and analyze potential risk factors for incomplete BM resection. Patients with BM resection and available postoperative MRI were included. Intraoperative estimation of EOR by the neurosurgeon was noted. Additionally, EOR was determined by postoperative MRI. Potential risk factors for incomplete resection were investigated. There were 145 patients with 163 BMs included. According to postoperative MRI, complete resection was achieved in 103 (63%) BMs, and resection was incomplete in 44 (27%) BMs. Postoperative MRI detected unexpected residual tumor in 32 (25%) BMs, and a misjudgment of the EOR by the neurosurgeon was found in 29% of cases. Regarding risk factors for incomplete resection, preoperative tumor volume was significantly larger in incompletely resected BMs compared with completely resected BMs (P = 0.011). All other analyzed risk factors had no significant influence on EOR. Our data indicate that postoperative MRI is able to detect a high portion of unexpected residual tumors after surgery of BMs. Preoperative tumor volume in particular represents an important risk factor for incomplete resection, and hence neurosurgeons should pay special attention to avoid residual tumor tissue. [ABSTRACT FROM AUTHOR]