Robot-assisted stereotactic brain biopsy: systematic review and bibliometric analysis

Three-Dimensional Structure Light Robot-Assisted Frameless Stereotactic Brain Biopsy

BACKGROUND AND OBJECTIVES

To assess the feasibility, accuracy, and safety of 3-dimensional (3D) structure light robot-assisted frameless stereotactic brain biopsy.

METHODS

Five consecutive patients (3 males, 2 females) were included in this study. The patients' clinical, imaging, and histological data were analyzed, and all patients received a 3D structure light robot-assisted frameless stereotactic brain biopsy. The raw and/or analyzed data of the study are available from the corresponding author.

RESULTS

The statistical results showed a mean age of 59.6 years (range 40-70 years), a mean target depth of 60.9 mm (range 53.5-65.8 mm), a mean radial error of 1.2 ± 0.7 mm (mean ± SD), a mean depth error of 0.7 ± 0.3 mm, and a mean absolute tip error of 1.5 ± 0.6 mm. The calculated Pearson product-moment correlation coefficient ( r = 0.23) revealed no correlation between target depth and absolute tip error. All biopsy needles were placed in line with the planned trajectory successfully, and diagnostic specimens were harvested in all cases. Histopathological analysis revealed lymphoma (2 cases), lung adenocarcinoma (1 case), glioblastoma multiforme (1 case), and oligodendroglioma (1 case).

CONCLUSION

Surface registration using the 3D structure light technique is fast and precise because of the achievable million-scale point cloud data of the head and face. 3D structure light robot-assisted frameless stereotactic brain biopsy is feasible, accurate, and safe.

Robotic alignment system Cirq (Brainlab) for navigated brain tumor biopsies in children

INTRODUCTION

The Cirq robotic alignment system (Brainlab, Munich, Germany) is a manually adjustable electronic arm with a robotic alignment module on its distal end, enabling the neurosurgeon to automatically and accurately align surgical instruments to a preoperatively planned trajectory. In this study, we share our first experiences and results using Cirq for intracranial tumor biopsy in children.

METHODS

From May 2021 until October 2022, all consecutive patients that underwent a brain tumor biopsy using Cirq were included and compared to a historical cohort of patients biopsied with the non-robotic system Varioguide (Brainlab, Munich, Germany). Patient-related data, tumor-related data, and surgery-related data were collected. Registration accuracy was calculated for different patient-to-image registration methods. Pre- and postoperative images were fused, and entry error, target error, and angulation error were calculated.

RESULTS

Thirty-seven patients, aged 1-19 years, were included (14 with Cirq and 23 with Varioguide). An integrated histopathological and molecular diagnosis was acquired in all cases. Patient-to-image registration was significantly more accurate when based on bone screw fiducials combined with intraoperative CT, as compared to surface matching or skin fiducials. The target error (Euclidian distance) was 5.3 mm for Cirq as compared to 8.3 mm for Varioguide, but this was not statistically significant. Entry error and angulation error were also not significantly different between both groups.

CONCLUSION

Intracranial biopsy with the Cirq robotic system is feasible and safe, and its accuracy does not differ from the Varioguide system.

Clinical experiences and learning curves from robot-assisted neurosurgical biopsies with Stealth Autoguide™

Background

Biopsies of intracranial lesions are a cornerstone in the diagnosis of unresectable tumors to guide neurooncological treatment; however, the procedure is also associated with risks. The results from the cranial robot guidance system Stealth Autoguide™ were studied after introduction at a neurosurgical department. Primary aims include the presentation of clinical and radiological data, accuracy of radiological diagnosis, learning curves of the new technology, diagnostic yield, and precision. The secondary aim was to study complications.

Methods

Retrospective data inclusion was performed on patients ≥ 18 years undergoing biopsy with Stealth Autoguide™ due to suspected brain tumors in the first 3 years after the introduction of the technique. Data regarding clinical characteristics, intraoperative variables, pathological diagnosis, and complications were recorded. Analyses of learning curves were performed.

Results

A total of 79 procedures were performed on 78 patients with a mean age of 62 years (SD 12.7, range 23-82), 30.8% were female. Tumors were often multifocal (63.3%) and supratentorial (89.9%). The diagnostic yield was 87.3%. The first-hand radiological diagnosis was correct in 62.0%. A slight decrease in operation time was observed, although not significant. The surgeon contributed to 12% of the variability.

Conclusions

Robot-assisted biopsies with Stealth Autoguide™ seem to be comparable, with regards to complications, to frame-based and other frameless neurosurgical biopsies. Learning curves demonstrated no statistical differences in time of surgery and only 12% surgeon-related variation (ie, variation caused by the change of performing surgeon), suggesting a successful implementation of this technical adjunct.

Revolutionizing orthopedics: a comprehensive review of robot-assisted surgery, clinical outcomes, and the future of patient care

Robotic-assisted orthopedic surgery (RAOS) is revolutionizing the field, offering the potential for increased accuracy and precision and improved patient outcomes. This comprehensive review explores the historical perspective, current robotic systems, advantages and limitations, clinical outcomes, patient satisfaction, future developments, and innovation in RAOS. Based on systematic reviews, meta-analyses, and recent studies, this article highlights the most significant findings and compares RAOS to conventional techniques. As robotic-assisted surgery continues to evolve, clinicians and researchers must stay informed and adapt their practices to provide optimal patient care. Evidence from published studies corroborates these claims, highlighting superior component positioning, decreased incidence of complications, and heightened patient satisfaction. However, challenges such as costs, learning curves, and technical issues must be resolved to fully capitalize on these advantages.

Surgical Characteristics of Intracranial Biopsy Using a Frameless Stereotactic Robotic Platform: A Single-Center Experience

BACKGROUND AND OBJECTIVES

Cranial robotics are a burgeoning field of neurosurgery. To date, all cranial robotic systems described have been computerized, arm-based instruments that take up significant space in the operating room. The Medtronic Stealth Autoguide robot has a smaller operating room footprint and offers multiaxial, frame-based surgical targeting. The authors set out to define the surgical characteristics of a novel robotic platform for brain biopsy in a large patient cohort.

METHODS

Patients who underwent stereotactic biopsy using the Stealth Autoguide cranial robotic platform from July 2020 to March 2023 were included in this study. Clinical, surgical, and histological data were collected and analyzed.

RESULTS

Ninety-six consecutive patients (50 female, 46 male) were included. The mean age at biopsy was 53.7 ± 18.0 years. The mean target depth was 68.2 ± 15.3 mm. The biopsy diagnostic tissue acquisition rate was 100%. The mean time from incision to biopsy tissue acquisition was 15.4 ± 9.9 minutes. Target lesions were located throughout the brain: in the frontal lobe (n = 32, 33.3%), parietal lobe (n = 21, 21.9%), temporal lobe (n = 22, 22.9%), deep brain nuclei/thalamus (n = 13, 13.5%), cerebellum (n = 7, 7.3%), and brainstem (n = 1, 1.0%). Most cases were gliomas (n = 75, 78.2%). Patients were discharged home on postoperative day 0 or 1 in 62.5% of cases. A total of 7 patients developed postoperative complications (7.2%).

CONCLUSION

This cranial robotic platform can be used for efficient, safe, and accurate cranial biopsies that allow for reliable diagnosis of intracranial pathology in a minimally invasive setting.

The complexities of treating brain and spinal cord tumors: a review of current approaches

This article provides an overview of brain and spinal cord tumours, including their types, diagnosis, and treatment approaches. Brain and spinal cord tumours are complex and can be caused by various factors. They can be divided into two main categories, primary and metastatic tumours, which present their own unique challenges and complexities when it comes to treatment. Diagnosing brain and spinal cord tumours requires a careful evaluation of the patient's medical history and symptoms, as well as a variety of diagnostic tools and techniques. Treatment approaches include surgery, radiation therapy, and chemotherapy, each with its own benefits and drawbacks. The choice of treatment depends on the type and location of the tumour, as well as the patient's individual needs and preferences. Despite advances in treatment, there is a pressing need for further research to improve the effectiveness and safety of these treatments.

Stereoelectroencephalography Implantation Using Frameless Neuronavigation and Varioguide: Prospective Analysis of Accuracy and Safety in a Case Series of 11 Patients

BACKGROUND

Stereoencephalography (SEEG) is becoming a widespread diagnostic procedure for drug-resistant epilepsy investigation. Techniques include frame-based and robot-assisted implantation, and more recently, frameless neuronavigated systems (FNSs). Despite its recent use, the accuracy and safety of FNS are still under investigation.

OBJECTIVE

To assess in a prospective study the accuracy and safety of a specific FNS use for SEEG implantation.

METHODS

Twelve patients who underwent SEEG implantation using FNS (Varioguide [Brainlab]) were included in this study. Data were collected prospectively and included demographic data, postoperative complications, functional results, and implantation characteristics (i.e., duration and number of electrodes). Further analysis included accuracy at entry point and target using measurements of the euclidean distance between planned and actual trajectories.

RESULTS

Eleven patients underwent SEEG-FNS implantation from May 2019 to March 2020. One patient did not undergo surgery because of a bleeding disorder. The mean target deviation was 4.06 mm, and mean entry point deviation was 4.2 mm, with insular electrodes significantly more deviated. Results excluding insular electrodes showed a mean target deviation of 3.66 mm and a mean entry point deviation of 3.77 mm. No severe complications occurred; a few mild to moderate adverse events were reported (1 superficial infection, 1 seizure cluster, and 3 transient neurologic impairments). The mean implantation duration by electrodes was 18.5 minutes.

CONCLUSIONS

Implantation of depth electrodes for SEEG using FNS seems to be safe, but larger prospective studies are needed to validate these results. Accuracy is sufficient for noninsular trajectories but warrant caution for insular trajectories with statistically significantly less accuracy.

Frameless Robotic-Assisted Biopsy of Pediatric Brainstem Lesions: A Systematic Review and Meta-Analysis of Efficacy and Safety

BACKGROUND

Pediatric brainstem lesions are diagnoses that require tissue sampling to advance our understanding of them and their management. Frameless, robot-assisted biopsy of these lesions has emerged as a novel, viable biopsy approach. Correspondingly, the aim of this study was to quantitively and qualitatively summarize the contemporary literature regarding the likelihood of achieving tumor diagnosis and experiencing any postoperative complications.

METHODS

Searches of 7 electronic databases from inception to September 2022 were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were screened against prespecified criteria. Outcomes were pooled by random-effects meta-analyses of proportions where possible.

RESULTS

A total of 8 cohort studies satisfied all criteria. They described 99 pediatric patients with brainstem lesions in whom frameless, robot-assisted biopsy was involved in their work-up. There were 62 (63%) male and 37 (37%) female patients with a median age of 9 years at time of biopsy. Overall, all patients had sufficient tissue obtained by initial biopsy for evaluation. Pooled estimate of achieving tumor diagnosis was 100% (95% confidence interval [CI] 97%-100%) across all studies with a high degree of certainty. Across all studies, there were no cases of procedure-related mortality. The pooled estimates of transient and permanent complications after biopsy were 10% (95% CI 4%-19%) and 0% (95% CI 0%-2%), respectively, of very low and low degrees of certainty each.

CONCLUSIONS

The contemporary metadata demonstrates the frameless, robot-assisted biopsy of pediatric brainstem lesions is both effective and safe when performed in an experienced setting. Further research is needed to augment robot and automated technologies into workup algorithms.

Learning curves in robotic neurosurgery: a systematic review

The transition to performing procedures robotically generally entails a period of adjustment known as a learning curve as the surgeon develops a familiarity with the technology. However, no study has comprehensively examined robotic learning curves across the field of neurosurgery. We conducted a systematic review to characterize the scope of literature on robotic learning curves in neurosurgery, assess operative parameters that may involve a learning curve, and delineate areas for future investigation. PubMed, Embase, and Scopus were searched. Following deduplication, articles were screened by title and abstract for relevance. Remaining articles were screened via full text for final inclusion. Bibliographic and learning curve data were extracted. Of 746 resultant articles, 32 articles describing 3074 patients were included, of which 23 (71.9%) examined spine, 4 (12.5%) pediatric, 4 (12.5%) functional, and 1 (3.1%) general neurosurgery. The parameters assessed for learning curves were heterogeneous. In total, 8 (57.1%) of 14 studies found reduced operative time with increased cases, while the remainder demonstrated no learning curve. Six (60.0%) of 10 studies reported reduced operative time per component with increased cases, while the remainder indicated no learning curve. Radiation time, radiation time per component, robot time, registration time, setup time, and radiation dose were assessed by ≤ 4 studies each, with 0-66.7% of studies demonstrated a learning curve. Four (44.4%) of 9 studies on accuracy showed improvement over time, while the others indicated no improvement over time. The number of cases required to reverse the learning curve ranged from 3 to 75. Learning curves are common in robotic neurosurgery. However, existing studies demonstrate high heterogeneity in assessed parameters and the number of cases that comprise the learning curve. Future studies should seek to develop strategies to reduce the number of cases required to reach the learning curve.

Modular robotic platform for precision neurosurgery with a bio-inspired needle: System overview and first in-vivo deployment

Over the past 10 years, minimally invasive surgery (MIS) has shown significant benefits compared to conventional surgical techniques, with reduced trauma, shorter hospital stays, and shorter patient recovery times. In neurosurgical MIS procedures, inserting a straight tool (e.g. catheter) is common practice in applications ranging from biopsy and laser ablation, to drug delivery and fluid evacuation. How to handle tissue deformation, target migration and access to deep-seated anatomical structures remain an open challenge, affecting both the preoperative planning phase and eventual surgical intervention. Here, we present the first neurosurgical platform in the literature, able to deliver an implantable steerable needle for a range of diagnostic and therapeutic applications, with a short-term focus on localised drug delivery. This work presents the system's architecture and first in vivo deployment with an optimised surgical workflow designed for pre-clinical trials with the ovine model, which demonstrate appropriate function and safe implantation.

Previous, current, and future stereotactic EEG techniques for localising epileptic foci

INTRODUCTION

Drug-resistant focal epilepsy presents a significant morbidity burden globally, and epilepsy surgery has been shown to be an effective treatment modality. Therefore, accurate identification of the epileptogenic zone for surgery is crucial, and in those with unclear noninvasive data, stereoencephalography is required.

AREAS COVERED

This review covers the history and current practices in the field of intracranial EEG, particularly analyzing how stereotactic image-guidance, robot-assisted navigation, and improved imaging techniques have increased the accuracy, scope, and use of SEEG globally.

EXPERT OPINION

We provide a perspective on the future directions in the field, reviewing improvements in predicting electrode bending, image acquisition, machine learning and artificial intelligence, advances in surgical planning and visualization software and hardware. We also see the development of EEG analysis tools based on machine learning algorithms that are likely to work synergistically with neurophysiology experts and improve the efficiency of EEG and SEEG analysis and 3D visualization. Improving computer-assisted planning to minimize manual input from the surgeon, and seamless integration into an ergonomic and adaptive operating theater, incorporating hybrid microscopes, virtual and augmented reality is likely to be a significant area of improvement in the near future.

A Comparation Between Frame-Based and Robot-Assisted in Stereotactic Biopsy

Introduction

Frame-based stereotactic biopsy is well-established to play an essential role in neurosurgery. In recent years, different robotic devices have been introduced in neurosurgery centers. This study aimed to compare the SINO surgical robot-assisted frameless brain biopsy with standard frame-based stereotactic biopsy in terms of efficacy, accuracy and complications.

Methods

A retrospective analysis was performed on 151 consecutive patients who underwent stereotactic biopsy at Chongqing Sanbo Jiangling Hospital between August 2017 and December 2021. All patients were divided into the frame-based group (n = 47) and the SINO surgical robot-assisted group (n = 104). The data collected included clinical characteristics, diagnostic yield, operation times, accuracy, and postoperative complications.

Results

There was no significant difference in diagnostic yield between the frame-based group and the SINO surgical robot-assisted group (95.74 vs. 98.08%, p > 0.05). The mean operation time in the SINO surgical robot-assisted group was significantly shorter than in the frame-based group (29.36 ± 13.64 vs. 50.57 ± 41.08 min). The entry point error in the frame-based group was significantly higher than in the robot-assisted group [1.33 ± 0.40 mm (0.47–2.30) vs. 0.92 ± 0.27 mm (0.35–1.65), P < 0.001]. The target point error in the frame-based group was also significantly higher than in the robot-assisted group [1.63 ± 0.41 mm (0.74–2.65) vs. 1.10 ± 0.30 mm (0.69–2.03), P < 0.001]. Finally, there was no significant difference in postoperative complications between the two groups.

Conclusion

Robot-assisted brain biopsy becomes an increasingly mainstream tool in the neurosurgical procedure. The SINO surgical robot-assisted platform is as efficient, accurate and safe as standard frame-based stereotactic biopsy and provides a reasonable alternative to stereotactic biopsy in neurosurgery.

Bibliometric Analysis of Mexican Publications on Stereotactic and Functional Neurosurgery From 1949 to 2021

Background

Stereotactic and functional neurosurgery (SFN) is a rapidly evolving field and some emerging countries, especially Mexico, have made significant contributions to this discipline. A bibliometric analysis has never been performed in Latin America, and this would be particularly important to show the areas that remain poorly studied, and design research strategies for the future.

Methods

Scopus was queried using keywords pertaining to functional neurosurgery, restricting the affiliation country to Mexico, and considering documents published after 1949. Added to the initial search, a complementary literature exploration by author, considering the publications of the most productive neurosurgeons, was performed. A descriptive statistical analysis was carried out.

Results

From 5,109 articles, only 371 were eligible. Scientific production has gradually increased with time. Epilepsy (31%) and movement disorders (27.4%) were the most studied neurological conditions, whereas the other 41.6% corresponded to pain, behavior disorders, spinal cord injuries, neuromodulation, stereotactic biopsies, and SFN history. Level of evidence was predominantly level V (59.1%). Publication output is highly skewed to Mexico City, which represents 78.4% of national production. Relative to factors associated with impact of research, publications in English had more citations (28.5 mean citations per paper), and journals with an impact factor greater than one had more than 10 mean citations per paper.

Conclusions

Mexico has experienced an increase in the productivity of SFN literature, addressing the most prevalent issues in the country (epilepsy and motor disorders). However, it is necessary to report studies with a higher level of evidence, as well as to decentralize the research collaborating with national institutions outside Mexico City. On the other hand, it is imperative to promote scientific production in English and in high-impact indexed journals to increase the visibility of our production. We would like to call upon our colleagues in other countries to reproduce our methodology, in order to determine the factors associated with the impact and productivity on SFN research.

Tenets for the Proper Conduct and Use of Meta-Analyses: A Practical Guide for Neurosurgeons

Neurosurgeons today are inundated with rapidly amassing neurosurgical research publications. Systematic reviews and meta-analyses have consequently surged in popularity because, when executed properly, they constitute a high level of evidence and may save busy neurosurgeons many hours of combing and reviewing the literature for relevant articles. Meta-analysis refers to the quantitative (and discretionary) component of systematic reviews. It involves applying statistical techniques to combine effect sizes from multiple studies, which might offer more actionable insights than a systematic review without meta-analysis. Well-executed meta-analyses may prove instructive for clinical practice, but poorly conducted ones sow confusion and have the potential to cause harm. Unfortunately, recent audits have found the conduct and reporting of meta-analyses in neurosurgery (but also other surgical disciplines) to be relatively lackluster in methodologic rigor and compliance to established guidelines. Some of these deficiencies can be easily remedied through better awareness and adherence to prescribed standards-which will be reviewed in this article-but others stem from inherent problems with the source data (e.g., poor reporting of original research) as well as unique constraints faced by surgery as a field (e.g., lack of equipoise for randomized trials, or existence of learning curves for novel surgical procedures, which can lead to temporal heterogeneity), which may require unconventional tools (e.g., cumulative meta-analysis) to address. Therefore, it is also our goal to take stock of the unique issues encountered by surgeons who do meta-analysis and to highlight various techniques-some of which less well-known-to address such challenges.

Development of a spherical parallel manipulator for brain surgery applications: preliminary study on the dynamic analysis and verification

This study focuses on development, task planning, and dynamic analysis of a previously proposed spherical parallel robot manipulator that is conceptually enhanced to adapt various brain surgery scenarios. Conceptual design of the proposed manipulator was briefly introduced and explained. In order to simulate one of the possible surgery scenarios, a case study of craniotomy was designed along with its trajectory planning. Dynamic analysis of proposed manipulator was performed by Lagrange method, and required actuator torque values were calculated for the desired trajectory. At the end of the study, hardware verification was carried out on the manufactured prototype of the system by comparing both calculated/acquired torque values and desired/actual trajectories. Promising verification results in terms of system dynamics and trajectory execution were introduced.

Accuracy of Robotic and Frame-Based Stereotactic Neurosurgery in a Phantom Model

Background

The development of robotic systems has provided an alternative to frame-based stereotactic procedures. The aim of this experimental phantom study was to compare the mechanical accuracy of the Robotic Surgery Assistant (ROSA) and the Leksell stereotactic frame by reducing clinical and procedural factors to a minimum.

Methods

To precisely compare mechanical accuracy, a stereotactic system was chosen as reference for both methods. A thin layer CT scan with an acrylic phantom fixed to the frame and a localizer enabling the software to recognize the coordinate system was performed. For each of the five phantom targets, two different trajectories were planned, resulting in 10 trajectories. A series of five repetitions was performed, each time based on a new CT scan. Hence, 50 trajectories were analyzed for each method. X-rays of the final cannula position were fused with the planning data. The coordinates of the target point and the endpoint of the robot- or frame-guided probe were visually determined using the robotic software. The target point error (TPE) was calculated applying the Euclidian distance. The depth deviation along the trajectory and the lateral deviation were separately calculated.

Results

Robotics was significantly more accurate, with an arithmetic TPE mean of 0.53 mm (95% CI 0.41–0.55 mm) compared to 0.72 mm (95% CI 0.63–0.8 mm) in stereotaxy (p < 0.05). In robotics, the mean depth deviation along the trajectory was −0.22 mm (95% CI −0.25 to −0.14 mm). The mean lateral deviation was 0.43 mm (95% CI 0.32–0.49 mm). In frame-based stereotaxy, the mean depth deviation amounted to −0.20 mm (95% CI −0.26 to −0.14 mm), the mean lateral deviation to 0.65 mm (95% CI 0.55–0.74 mm).

Conclusion

Both the robotic and frame-based approach proved accurate. The robotic procedure showed significantly higher accuracy. For both methods, procedural factors occurring during surgery might have a more relevant impact on overall accuracy.

Care of the Patient Undergoing Robotic-Assisted Brain Biopsy With Stereotactic Navigation: An Overview

Brain tumors can cause pressure, swelling, and functional changes to the surrounding tissue and lead to sensorimotor symptoms. Such tumors are either benign or malignant and their origin can be primary or metastatic. Although diagnostic studies (eg, computed tomography and magnetic resonance imaging) can reveal a mass and provide information on its location, size, and relationship to surrounding structures, the most definitive way to make a diagnosis requires a brain biopsy tissue sample. The robotic-assisted technique with stereotactic navigation allows the neurosurgeon to merge preoperative scans with a computer program to provide a map of the planned surgical trajectory and use the robot to obtain the biopsy. The robotic-assisted brain biopsy with navigation provides improved accuracy with small incisions that may not be possible using non-robotic-assisted techniques. This article provides background information and an overview of the nursing considerations for patients undergoing robotic-assisted brain biopsy procedures.

Frameless robot-assisted stereotactic biopsies for lesions of the brainstem-a series of 103 consecutive biopsies

PURPOSE

Targeted treatment for brainstem lesions requires above all a precise histopathological and molecular diagnosis. In the current technological era, robot-assisted stereotactic biopsies represent an accurate and safe procedure for tissue diagnosis. We present our center's experience in frameless robot-assisted biopsies for brainstem lesions.

METHODS

We performed a retrospective analysis of all patients benefitting from a frameless robot-guided stereotactic biopsy at our University Hospital, from 2001 to 2017. Patients consented to the use of data and/or images. The NeuroMate® robot (Renishaw™, UK) was used. We report on lesion location, trajectory strategy, histopathological diagnosis and procedure safety.

RESULTS

Our series encompasses 96 patients (103 biopsies) treated during a 17 years period. Mean age at biopsy: 34.0 years (range 1-78). Most common location: pons (62.1%). Transcerebellar approach: 61 procedures (59.2%). Most common diagnoses: diffuse glioma (67.0%), metastases (7.8%) and lymphoma (6.8%). Non conclusive diagnosis: 10 cases (9.7%). After second biopsy this decreased to 4 cases (4.1%). Overall biopsy diagnostic yield: 95.8%. Permanent disability was recorded in 3 patients (2.9%, all adults), while transient complications in 17 patients (17.7%). Four cases of intra-tumoral hematoma were recorded (one case with rapid decline and fatal issue). Adjuvant targeted treatment was performed in 72.9% of patients. Mean follow-up (in the Neurosurgery Department): 2.2 years.

CONCLUSION

Frameless robot-assisted stereotactic biopsies can provide the initial platform towards a safe and accurate management for brainstem lesions, offering a high diagnostic yield with low permanent morbidity.

High Precision Bone Cutting by Er: YAG Lasers Might Minimize the Invasiveness of Navigated Brain Biopsies

Biopsies of brain tissue are sampled and examined to establish a diagnosis and to plan further treatment, e.g. for brain tumors. The neurosurgical procedure of sampling brain tissue for histologic examination is still a relatively invasive procedure that carries several disadvantages. The “proof of concept”-objective of this study is to answer the question if laser technology might be a potential tool to make brain biopsies less invasive, faster and safer. Laser technology might carry the opportunity to miniaturize the necessary burr hole and also to angulate the burr hole much more tangential in relation to the bone surface in order to take biopsies from brain regions that are usually only difficult and hazardous to access. We examined if it is possible to miniaturize the hole in the skull bone to such a high extent that potentially the laser-created canal itself may guide the biopsy needle with sufficient accuracy. The 2-dimensional, i.e. radial tolerance of the tip of biopsy needles inserted in these canals was measured under defined lateral loads which mimic mechanical forces applied by a surgeon. The canals through the skull bones were planned in angles of 90° (perpendicular) and 45° relative to the bone surface. We created a total of 33 holes with an Er : YAG laser in human skull bones. We could demonstrate that the achievable radial tolerance concerning the guidance of a biopsy needle by a laser created bone canal is within the range of the actual accuracy of a usual navigated device if the canal is at least 4 mm in length. Lateral mechanical loads applied to the biopsy needle had only minor impact on the measurable radial tolerance. Furthermore, in contrast to mechanical drilling systems, laser technology enables the creation of bone canals in pointed angles to the skull bone surface. The latter opens the perspective to sample biopsies in brain areas that are usually not or only hazardous to access.

A novel technique for fence-post tube placement in glioma using the robot-guided frameless neuronavigation technique under exoscope surgery: patient series

BACKGROUND

Robotic technology is increasingly used in neurosurgery. The authors reported a new technique for fence-post tube placement using robot-guided frameless stereotaxic technology with neuronavigation in patients with glioma.

OBSERVATIONS

Surgery was performed using the StealthStation S8 linked to the Stealth Autoguide cranial robotic guidance platform and a high-resolution three-dimensional (3D) surgical microscope. A surgical plan was created to determine the removal area using fence-post tube placement at the tumor and normal brain tissue boundary. Using this surgical plan, the robotic system allowed quick and accurate fence-post tube positioning, automatic alignment of the needle insertion and measurement positions in the brain, and quick and accurate puncture needle insertion into the brain tumor. Use of a ventricular drainage tube for the outer needle cylinder allowed placement of the puncture needle in a single operation. Furthermore, use of a high-resolution 3D exoscope allowed the surgeon to simultaneously view the surgical field image and the navigation screen with minimal line-of-sight movement, which improved operative safety. The position memory function of the 3D exoscope allowed easy switching between the exoscope and the microscope and optimal field of view adjustment.

LESSONS

Fence-post tube placement using robot-guided frameless stereotaxic technology, neuronavigation, and an exoscope allows precise glioma resection.

Reassessing the Role of Brain Tumor Biopsy in the Era of Advanced Surgical, Molecular, and Imaging Techniques-A Single-Center Experience with Long-Term Follow-Up

Brain biopsy is the gold standard in order to establish the diagnosis of unresectable brain tumors. Few studies have investigated the long-term outcomes of biopsy patients. The aim of this single-institution-based study was to assess the concordance between radiological and histopathological diagnoses, and the long-term patient outcome. Ninety-three patients who underwent brain biopsy in the last 5 years were analyzed. We included patients treated with stereotactically guided needle, open, and neuroendoscopic biopsies. Most patients (86%) received needle biopsy. Gliomas and primary brain lymphomas comprised 88.2% of cases. The diagnostic yield was 95.7%. Serious complication and death rates were 3.2% and 2.1%, respectively. The concordance rate between radiological and histological diagnoses was 93%. Notably, the positive predictive value of radiological diagnosis of lymphoma was 100%. Biopsy allowed specific treatment in 72% of cases. Disease-related neurological worsening was the main reason that precluded adjuvant treatment. Adjuvant treatment, in turn, was the strongest prognostic factor, since the median overall survival was 11 months with vs. 2 months without treatment (p = 0.0002). Finally, advanced molecular evaluations can be obtained on glioma biopsy specimens to provide integrated diagnoses and individually tailored treatments. We conclude that, despite the huge advances in imaging techniques, biopsy is required when an adjuvant treatment is recommended, particularly in gliomas.

Full-field MRI measurements of in-vivo positional brain shift reveal the significance of intra-cranial geometry and head orientation for stereotactic surgery

Positional brain shift (PBS), the sagging of the brain under the effect of gravity, is comparable in magnitude to the margin of error for the success of stereotactic interventions ([Formula: see text] 1 mm). This non-uniform shift due to slight differences in head orientation can lead to a significant discrepancy between the planned and the actual location of surgical targets. Accurate in-vivo measurements of this complex deformation are critical for the design and validation of an appropriate compensation to integrate into neuronavigational systems. PBS arising from prone-to-supine change of head orientation was measured with magnetic resonance imaging on 11 young adults. The full-field displacement was extracted on a voxel-basis via digital volume correlation and analysed in a standard reference space. Results showed the need for target-specific correction of surgical targets, as a significant displacement ranging from 0.52 to 0.77 mm was measured at surgically relevant structures. Strain analysis further revealed local variability in compressibility: anterior regions showed expansion (both volume and shape change), whereas posterior regions showed small compression, mostly dominated by shape change. Finally, analysis of correlation demonstrated the potential for further patient- and intervention-specific adjustments, as intra-cranial breadth and head tilt correlated with PBS reaching statistical significance.

Comparison of robotic and manual implantation of intracerebral electrodes: a single-centre, single-blinded, randomised controlled trial

There has been a significant rise in robotic trajectory guidance devices that have been utilised for stereotactic neurosurgical procedures. These devices have significant costs and associated learning curves. Previous studies reporting devices usage have not undertaken prospective parallel-group comparisons before their introduction, so the comparative differences are unknown. We study the difference in stereoelectroencephalography electrode implantation time between a robotic trajectory guidance device (iSYS1) and manual frameless implantation (PAD) in patients with drug-refractory focal epilepsy through a single-blinded randomised control parallel-group investigation of SEEG electrode implantation, concordant with CONSORT statement. Thirty-two patients (18 male) completed the trial. The iSYS1 returned significantly shorter median operative time for intracranial bolt insertion, 6.36 min (95% CI 5.72–7.07) versus 9.06 min (95% CI 8.16–10.06), p = 0.0001. The PAD group had a better median target point accuracy 1.58 mm (95% CI 1.38–1.82) versus 1.16 mm (95% CI 1.01–1.33), p = 0.004. The mean electrode implantation angle error was 2.13° for the iSYS1 group and 1.71° for the PAD groups (p = 0.023). There was no statistically significant difference for any other outcome. Health policy and hospital commissioners should consider these differences in the context of the opportunity cost of introducing robotic devices.

Trial registration: ISRCTN17209025 (https://doi.org/10.1186/ISRCTN17209025).

Comparison of Frame-Based Versus Frameless Image-Guided Intracranial Stereotactic Brain Biopsy: A Retrospective Analysis of Safety and Efficacy

BACKGROUND

A definitive diagnosis of brain lesions not amenable to surgery is mainly made by stereotactic needle biopsy. The diagnostic yield and safety of the frameless vs frame-based image-guided stereotactic techniques is unclear.

OBJECTIVE

To evaluate the safety and accuracy of frameless vs frame-based stereotactic brain biopsy techniques.

METHODS

A total of 278 patients (153 men, mean age 65.5 years) with intra-axial brain lesions underwent frame-based (n=148) or frameless image-guided stereotactic brain biopsy (n=130) using a minimally invasive twist drill technique during 2010-2016 at Sheba Medical Center. Demographic, imaging, and clinical data were retrospectively analyzed.

RESULTS

The diagnostic yield (>90%) did not differ significantly between groups. Overall morbidity (6.8% vs 8.5%), incidence of permanent neurologic deficits (2.1% vs 1.6%), mortality rate (0.7% vs 0.8%), and postoperative computed tomography-detected asymptomatic (14.2% vs 16.1%) and symptomatic (2.0% vs 1.6%) bleeding also did not differ significantly between the frame-based and frameless cohorts, respectively. The diagnostic yield and complication rates related to the biopsy technique were not significantly associated with sex; age; entry angle to the skull and skull thickness; lesion location or depth, or radiologic characteristics. Diagnostic yield was significantly associated with the mean lesion volume. Smaller lesions were less diagnostic than larger lesions in both techniques (p=0.043 frame-based and p=0.048 frameless).

CONCLUSION

The frameless biopsy technique is as efficient as the frame-based brain biopsy technique with a low complication rate. Lesion volume was the only predictive factor of diagnostic yield. The minimally invasive twist drill technique is safe and efficient.

Mobile intraoperative CT-assisted frameless stereotactic biopsies achieved single-millimeter trajectory accuracy for deep-seated brain lesions in a sample of 7 patients

Background

Brain biopsies are crucial diagnostic interventions, providing valuable information for treatment and prognosis, but largely depend on a high accuracy and precision. We hypothesized that through the combination of neuronavigation-based frameless stereotaxy and MRI-guided trajectory planning with intraoperative CT examination using a mobile unit, one can achieve a seamlessly integrated approach yielding optimal target accuracy.

Methods

We analyzed a total of 7 stereotactic biopsy trajectories for a variety of deep-seated locations and different patient positions. After rigid head fixation, an intraoperative pre-procedural scan using a mobile CT unit was performed for automatic image fusion with the planning MRI images and a peri-procedural scan with the biopsy cannula in situ for verification of the definite target position. We then evaluated the radial trajectory error.

Results

Intraoperative scanning, surgery, computerized merging of MRI and CT images as well as trajectory planning were feasible without difficulties and safe in all cases. We achieved a radial trajectory deviation of 0.97 ± 0.39 mm at a trajectory length of 60 ± 12.3 mm (mean ± standard deviation). Repositioning of the biopsy cannula due to inaccurate targeting was not required.

Conclusion

Intraoperative verification using a mobile CT unit in combination with frameless neuronavigation-guided stereotaxy and pre-operative MRI-based trajectory planning was feasible, safe and highly accurate. The setting enabled single-millimeter accuracy for deep-seated brain lesions and direct detection of intraoperative complications, did not depend on a dedicated operating room and was seamlessly integrated into common stereotactic procedures.

The Path to Surgical Robotics in Neurosurgery

Robotic systems may help efficiently execute complicated tasks that require a high degree of accuracy, and this, in large part, explains why robotics have garnered widespread use in a variety of neurosurgical applications, including intracranial biopsies, spinal instrumentation, and placement of intracranial leads. The use of robotics in neurosurgery confers many benefits, and inherent limitations, to both surgeons and their patients. In this narrative review, we provide a historical overview of robotics and its implementation across various surgical specialties, and discuss the various robotic systems that have been developed specifically for neurosurgical applications. We also discuss the relative advantages of robotic systems compared to traditional surgical techniques, particularly as it pertains to integration of image guidance with the ability of the robotic arm to reliably execute pre-planned tasks. As more neurosurgeons adopt the use of robotics in their practice, we postulate that further technological advancements will become available that will help achieve improved technical capabilities, user experience, and overall patient clinical outcomes.

Comparison of frame-less robotic versus frame-based stereotactic biopsy of intracranial lesions

OBJECTIVE

Robotic guidance might be an alternative to classic stereotaxy for biopsies of intracranial lesions. Both methods were compared regarding time efficacy, histopathological results and complications.

METHODS

A retrospective analysis enrolling all patients undergoing robotic- or stereotactic biopsies between 01/2015 and 12/2018 was conducted. Trajectory planning was performed on magnetic resonance imaging (MRI). With the Robotic Surgery Assistant (ROSA), patient registration was accomplished using a facial laser scan in the operating room (OR), immediately followed by biopsy. In stereotaxy, patients were transported to the CT for Leksell Frame registration, followed by biopsy in the OR.

RESULTS

The average overall procedure time amounted in robotics to 169 min and in stereotaxy to 179 min (p = 0.005). The difference was greatest for temporal targets, amounting in robotics to 161 min and in stereotaxy to 188 min (p = 0,0007). However, the average time spent purely in the OR amounted in robotics to 140 min and in stereotaxy to 113 min (p < 0.001). In 150 robotic biopsies, diagnostic yield amounted to 98%, in 266 stereotactic biopsies to 91%. Symptomatic postoperative hemorrhages were observed in 3 patients (2%) in robotic biopsy and 7 patients (2,7%) in stereotactic biopsy.

CONCLUSION

Robotics showed a shorter overall procedure time as there is no need for a transport to the CT whereas the pure OR time was shorter in stereotaxy due to skipping the laser registration process. Diagnostic yield was higher in robotics, most likely due to case selection, complication rates were equal.

THE SAFETY AND EFFICACY OF ROBOT-ASSISTED STEREOTACTIC BIOPSY FOR BRAIN GLIOMA: EARLIEST INSTITUTIONAL EXPERIENCES AND EVALUATION OF LITERATURE

Robot-assisted brain tumor biopsy is becoming one of the most important innovative technologies in neurosurgical practice. The idea behind its engagement is to advance the safety and efficacy of the biopsy procedure, which is much in demand when planning the management of endocranial tumor pathology. Herein, we provide our earliest institutional experiences in utilizing this mesmerizing technology. Cranial robotic device was employed for stereotactic robot-assisted brain glioma biopsy in three consecutive patients from our series: an anaplastic isocitrate dehydrogenase (IDH) negative astrocytoma (WHO grade III) located in the right trigone region of the periventricular white matter; a low grade diffuse astrocytoma (WHO grade II) of bilateral thalamic region spreading into the right mesencephalic area; and an IDH-wildtype glioblastoma (WHO grade IV) of the right frontal lobe producing a contralateral midline shifting. Robot-assisted tumor biopsy was successfully performed to get tissue samples for histopathologic and immunohistochemical analysis. The adjacent tissue iatrogenic damage of the eloquent cortical areas was minimal, while the immediate postoperative recovery was satisfactory in all patients. In conclusion, considering the preliminary results of our early experiences, robot-assisted tumor biopsy was proven to be a feasible and accurate procedure when surgery for brain glioma was not an option. It may increase safety and precision, without expanding surgical time, being similarly effective when compared to standard stereotactic and manual biopsy. Using this method to provide accurate sampling for histopathologic and immunohistochemical analysis is a safe and easy way to determine management strategies and outcome of different types of brain glioma.

Artificial intelligence in dermatology and healthcare: An overview

Many aspects of our life are affected by technology. One of the most discussed advancements of modern technologies is artificial intelligence. It involves computational methods which in some way mimic the human thought process. Just like other branches, the medical field also has come under the ambit of artificial intelligence. Almost every field in medicine has been touched by its effect in one way or the other. Prominent among them are medical diagnosis, medical statistics, robotics, and human biology. Medical imaging is one of the foremost specialties with artificial intelligence applications, wherein deep learning methods like artificial neural networks are commonly used. artificial intelligence application in dermatology was initially restricted to the analysis of melanoma and pigmentary skin lesions, has now expanded and covers many dermatoses. Though the applications of artificial intelligence are ever increasing, large data requirements, interpretation of data and ethical concerns are some of its limitations in the present day.

Diagnosis and Management of Glioblastoma: A Comprehensive Perspective

Glioblastoma is the most common malignant brain tumor in adults. The current management relies on surgical resection and adjuvant radiotherapy and chemotherapy. Despite advances in our understanding of glioblastoma onset, we are still faced with an increased incidence, an altered quality of life and a poor prognosis, its relapse and a median overall survival of 15 months. For the past few years, the understanding of glioblastoma physiopathology has experienced an exponential acceleration and yielded significant insights and new treatments perspectives. In this review, through an original R-based literature analysis, we summarize the clinical presentation, current standards of care and outcomes in patients diagnosed with glioblastoma. We also present the recent advances and perspectives regarding pathophysiological bases as well as new therapeutic approaches such as cancer vaccination and personalized treatments.

Frameless stereotactic brain biopsy: A prospective study on robot-assisted brain biopsies performed on 32 patients by using the RONNA G4 system

BACKGROUND

We present a novel robotic neuronavigation system (RONNA G4), used for precise preoperative planning and frameless neuronavigation, developed by a research group from the University of Zagreb and neurosurgeons from the University Hospital Dubrava, Zagreb, Croatia. The aim of study is to provide comprehensive error measurement analysis of the system used for the brain biopsy.

METHODS

Frameless stereotactic robot-assisted biopsies were performed on 32 consecutive patients. Post-operative CT and MRI scans were assessed to precisely measure and calculate target point error (TPE) and entry point error (EPE).

RESULTS

The application accuracy of the RONNA system for TPE was 1.95 ± 1.11 mm, while for EPE was 1.42 ± 0.74 mm. The total diagnostic yield was 96.87%. Linear regression showed statistical significance between the TPE and EPE, and the angle of the trajectory on the bone.

CONCLUSION

The RONNA G4 robotic system is a precise and highly accurate autonomous neurosurgical assistant for performing frameless brain biopsies.

Preclinical Evaluation of the Stealth Autoguide Robotic Guidance Device for Stereotactic Cranial Surgery: A Human Cadaveric Study

INTRODUCTION

Stereotactic procedures are routinely performed for brain biopsies, deep brain stimulation, and placement of stereoelectroencephalography (SEEG) electrodes for epilepsy. The recently developed Stealth Autoguide (Medtronic, Minneapolis, MN, USA) device does not require patients to don a stereotactic frame. In this preclinical study, we sought to quantitatively compare the Stealth Autoguide robotic system to 2 devices commonly used in clinical practice: the Navigus biopsy system (Medtronic) and the Leksell stereotactic frame (Elekta Ltd., Stockholm, Sweden).

METHODS

In the first experimental setup, we compared target accuracy of the Stealth Autoguide to the Navigus system by using phantom heads filled with gelatin to simulate the brain tissue. In the second experimental setup, we inserted SEEG electrodes to targets within cadaveric heads in a simulated operating room environment.

RESULTS

Using a homogeneous gelatin-filled phantom 3D reconstruction of a human head, we found that using the Stealth Autoguide system, while maintaining accuracy, was faster to use than the Navigus system. In our simulated operating room environment using nonliving human cadaveric heads, we found the accuracy of the Stealth Autoguide robotic device to be comparable to that of the Leksell frame.

DISCUSSION/CONCLUSION

These results compare the use of the Stealth Autoguide robotic guidance system with commonly used stereotactic devices, and this is the first study to compare its use and accuracy with the Leksell frame. These findings provide mounting evidence that Stealth Autoguide will have potential clinical uses in various stereotactic neurosurgical procedures.

Computer Assisted Planning for Curved Laser Interstitial Thermal Therapy

Laser interstitial thermal therapy (LiTT) is a minimally invasive alternative to conventional open surgery for drug-resistant focal mesial temporal lobe epilepsy (MTLE). Recent studies suggest that higher seizure freedom rates are correlated with maximal ablation of the mesial hippocampal head, whilst sparing of the parahippocampal gyrus (PHG) may reduce neuropsychological sequelae. Current commercially available laser catheters are inserted following manually planned straight-line trajectories, which cannot conform to curved brain structures, such as the hippocampus, without causing collateral damage or requiring multiple insertions. The clinical feasibility and potential of curved LiTT trajectories through steerable needles has yet to be investigated. This is the focus of our work. We propose a GPU-accelerated computer-assisted planning (CAP) algorithm for steerable needle insertions that generates optimized curved 3D trajectories with maximal ablation of the amygdalohippocampal complex and minimal collateral damage to nearby structures, while accounting for a variable ablation diameter ( 5-15mm). Simulated trajectories and ablations were performed on 5 patients with mesial temporal sclerosis (MTS), which were identified from a prospectively managed database. The algorithm generated obstacle-free paths with significantly greater target area ablation coverage and lower PHG ablation variance compared to straight line trajectories. The presented CAP algorithm returns increased ablation of the amygdalohippocampal complex, with lower patient risk scores compared to straight-line trajectories. This is the first clinical application of preoperative planning for steerable needle based LiTT. This study suggests that steerable needles have the potential to improve LiTT procedure efficacy whilst improving the safety and should thus be investigated further.

Postoperative intracerebral haematomas following stereotactic biopsies: Poor planning or poor execution?

BACKGROUND

Postoperative intracerebral haematomas represent a serious complication following stereotactic biopsy. We investigated the possible underlying causes - poor planning or poor execution - of postoperative intracerebral haematomas following stereotactic biopsies.

METHODS

We performed a technical investigation using a retrospective single-centre consecutive series of robot-assisted stereotactic biopsies for a supratentorial diffuse glioma in adults. Each actual biopsy trajectory was reviewed to search for a conflict with an anatomical structure at risk.

RESULTS

From 379 patients, 12 (3.2%) presented with a postoperative intracerebral haematoma ≥20 mm on postoperative CT-scan (3 requiring surgical evacuation); 11 of them had available intraoperative imaging (bi-planar stereoscopic teleangiography x-rays at each biopsy site). The actual biopsy trajectory was similar to the planned biopsy trajectory in these 11 cases. In 72.7% (8/11) of these cases, the actual biopsy trajectory was found to contact a structure at risk (blood vessel and cerebral sulcus) and identified as the intracerebral haematoma origin.

CONCLUSIONS

Robot-assisted stereotactic biopsy is an accurate procedure. Postoperative intracerebral haematomas mainly derive from human-related errors during trajectory planning.

Robot-Assisted Stereotactic Biopsies in 377 Consecutive Adult Patients with Supratentorial Diffuse Gliomas: Diagnostic Yield, Safety, and Postoperative Outcomes

BACKGROUND

Multiple biopsy samples are warranted for the histomolecular diagnosis of diffuse gliomas in the current molecular era, which possibly increases morbidity.

OBJECTIVE

We assessed diagnostic yield, safety, and risk factors of postoperative morbidity after robot-assisted serial stereotactic biopsy sampling along 1 biopsy trajectory for diffuse gliomas.

METHODS

Observational retrospective analysis of consecutive magnetic resonance imaging-based robot-assisted stereotactic biopsies performed at a single institution to assess the diagnosis of nonresectable newly diagnosed supratentorial diffuse gliomas in adults (2006-2016).

RESULTS

In 377 patients, 4.2 ± 1.9 biopsy samples were obtained at 2.6 ± 1.2 biopsy sites. The histopathologic diagnosis was obtained in 98.7% of cases. Preoperative neurologic deficit (P = 0.030), biopsy site hemorrhage ≥20 mm (P = 0.004), and increased mass effect on postoperative imaging (P = 0.014) were predictors of a new postoperative neurologic deficit (7.7%). Postoperative neurologic deficit (P < 0.001) and increased mass effect on postoperative imaging (P = 0.014) were predictors of a Karnofsky Performance Status decrease ≥20 points postoperatively (4.0%). Increased intracranial pressure preoperatively (P = 0.048) and volume of the contrast-enhanced area ≥13 cm³ (P = 0.048) were predictors of an increased mass effect on postoperative imaging (4.4%). Preoperative Karnofsky Performance Status <70 (P = 0.045) and increased mass effect on postoperative imaging (P < 0.001) were predictors of mortality 1 month postoperatively (2.9%). Preoperative neurologic deficit (P = 0.005), preoperative Karnofsky Performance Status <70 (P < 0.001), subventricular zone contact (P = 0.004), contrast enhancement (P = 0.018), and steroid use (P = 0.003), were predictors of the inability to discharge to home postoperatively (37.0%).

CONCLUSIONS

Robot-assisted stereotactic biopsy sampling results in high diagnostic accuracy with low complication rates. Multiple biopsy sites and samples do not increase postoperative complications.

The IDEAL framework in neurosurgery: a bibliometric analysis

BACKGROUND

The Idea, Development, Exploration, Assessment and Long-term study (IDEAL) framework was created to provide a structured way for assessing and evaluating novel surgical techniques and devices.

OBJECTIVES

The aim of this paper was to investigate the utilization of the IDEAL framework within neurosurgery, and to identify factors influencing implementation.

METHODS

A bibliometric analysis of the 7 key IDEAL papers on Scopus, PubMed, Embase, Web of Science, and Google Scholar databases (2009-2019) was performed. A second journal-specific search then identified additional papers citing the IDEAL framework. Publications identified were screened by two independent reviewers to select neurosurgery-specific articles.

RESULTS

The citation search identified 1336 articles. The journal search identified another 16 articles. Following deduplication and review, 51 relevant articles remained; 14 primary papers (27%) and 37 secondary papers (73%). Of the primary papers, 5 (36%) papers applied the IDEAL framework to their research correctly; two were aligned to the pre-IDEAL stage, one to the Idea and Development stages, and two to the Exploration stage. Of the secondary papers, 21 (57%) explicitly discussed the IDEAL framework. Eighteen (86%) of these were supportive of implementing the framework, while one was not, and two were neutral.

CONCLUSION

The adoption of the IDEAL framework in neurosurgery has been slow, particularly for early-stage neurosurgical techniques and inventions. However, the largely positive reviews in secondary literature suggest potential for increased use that may be achieved with education and publicity.

Frame-based stereotactic biopsy of deep-seated and midline structures in 511 procedures: feasibility, risk profile, and diagnostic yield

OBJECTIVES

We evaluated the feasibility, safety, and diagnostic yield of frame-based stereotactic biopsies (SB) in lesions located in deep-seated and midline structures of the brain to analyze these parameters in comparison to other brain areas.

PATIENTS AND METHODS

In a retrospective, tertiary care single-center analysis, we identified all patients who received SB for lesions localized in deep-seated and midline structures (corpus callosum, basal ganglia, pineal region, sella, thalamus, and brainstem) between January 1996 and June 2015. Study participants were between 1 and 82 years. We evaluated the feasibility, procedural complications (mortality, transient and permanent morbidity), and diagnostic yield. We further performed a risk analysis of factors influencing the latter parameters. Chi-square test, Student t test, and Mann-Whitney rank-sum test were used for statistical analysis.

RESULTS

Four hundred eighty-nine patients receiving 511 SB procedures (median age 48.5 years, range 1-82; median Karnofsky Performance Score 80%, range 50-100%, 43.8% female/56.2% male) were identified. Lesions were localized in the corpus callosum (29.5%), basal ganglia (17.0%), pineal region (11.5%), sella (7.8%), thalamus (4.3%), brainstem (28.8%), and others (1.1%). Procedure-related mortality was 0%, and permanent morbidity was 0.4%. Transient morbidity was 9.6%. Histological diagnosis was possible in 99.2% (low-grade gliomas 16.2%, high-grade gliomas 40.3%, other tumors in 27.8%, no neoplastic lesions 14.5%, no definitive histological diagnosis 0.8%). Only the pons location correlated significantly with transient morbidity (p < 0.001).

CONCLUSION

In experienced centers, frame-based stereotactic biopsy is a safe diagnostic tool with a high diagnostic yield also for deep-seated and midline lesions.

The diagnostic quality of needle brain biopsy specimens obtained with different sampling methods - Experimental study

The aim is to examine whether brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with defined vacuum pressure, a novel needle rotation method, and using different needle type - Laitinen or Nashold. Moreover the paper aims to answer the question: Does vacuum and mechanical injury resulting from different sampling methods damage the tissue specimen challenging the diagnosis?. Eight hundred biopsy specimens from fresh swine brains were obtained using Nashold and Laitinen brain biopsy needles through inner cannula cutting or needle rotation sampling at vacuum pressure, from 0 to 0.06 MPa. The specimen weight and tissue quality for microscopic assessment were evaluated using the Mair score. Rising aspiration pressure increased the biopsy sample weight. Needle rotation delivered larger biopsy samples than the standard method. Laitinen provided larger samples than the Nashold needle, with the same sampling method or vacuum pressure. A higher histopathological diagnostic quality of tissue was obtained with the Laitinen needle than with Nashold, with higher vacuum pressure than lower pressure and finally with needle rotation than the standard method. No tissue damage caused by higher suction pressure or method of tissue separation was documented. Brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with higher vacuum pressure, a novel needle rotation method and with Laitinen needle. Higher suction pressure and sampling methods did not cause tissue damage.

Structural design of a positioning spherical parallel manipulator to be utilized in brain biopsy

BACKGROUND

During the last decades, there has been a great increase in the usage of robotic systems during surgeries in order to reach increased operational precision, reduced operation times, enhanced recovery periods, low infection risks, and limited scar formations for aesthetic reasons. In light of this, the current study focuses on the field of robotic surgery by introducing the kinematic structure of the precise robotic positioning manipulator for brain biopsy.

METHODOLOGY

Throughout the study, two degrees of freedom spherical parallel robot manipulator was proposed in order to position brain biopsy needle precisely during the brain biopsy operation on the target workspace.

RESULTS

Direct and inverse kinematics of the manipulator were carried out parametrically by using quaternion algebra. The prototype of the manipulator was manufactured by rapid prototyping for hardware verification.

CONCLUSIONS

Hardware verification of the manufactured prototype was completed distinctly by using motion capture cameras and manufactured mock-up setup that mimics tumour locations inside the brain. Successful verification results in terms of precision were achieved.

Robot-assisted stereotactic brainstem biopsy in children: prospective cohort study

Tumours located within the brainstem comprise approximately a tenth of all paediatric brain tumours. Surgical biopsy of these tumours is technically challenging and has historically been associated with considerable risk. To this end, robot-assisted surgery theoretically allows for increased accuracy and precision. In this study we report our experience using the Neuromate robot (Renishaw, Gloucestershire, UK) to perform robot-assisted stereotactic biopsy in children with tumours located within the brainstem. An uncontrolled prospective cohort study was performed (phase II) according to the IDEAL model for safe surgical innovation. All cases were recorded on a prospectively maintained database. The database was searched over a 2-year period between the 1st December 2015 and the 31st November 2017 to identify all children with brainstem tumours that underwent robot-assisted stereotactic brain biopsy. When accessible, the post-operative MRI scans and pre-operative plans were compared to assess the target point localisation error (TPLE). Adverse events were recorded prospectively according to whether they resulted in increased hospital stay, caused neurological injury, or lead to death. In all, 11 consecutive children were identified with brain tumours located within the brainstem. In 10/11 cases specimens were diagnostic; in the remaining case a further biopsy was successful. The most frequent pathology was DIPG (7/15). Seven patients underwent an early post-operative volumetric MRI; the calculated median TPLE was 2.7 mm (range 0.5-4.2 mm). There were no surgical complications noted. Robot-assisted stereotactic biopsy in children appears to be feasible and safe. Research databases and comparative studies are warranted to further assess the technique.

Pediatric Central Nervous System Tumors: State-of-the-Art and Debated Aspects

Pediatric neuro-oncology surgery continues to progress in sophistication, largely driven by advances in technology used to aid the following aspects of surgery: operative planning (advanced MRI techniques including fMRI and DTI), intraoperative navigation [preoperative MRI, intra-operative MRI (ioMRI) and intra-operative ultrasound (ioUS)], tumor visualization (microscopy, endoscopy, fluorescence), tumor resection techniques (ultrasonic aspirator, micro-instruments, micro-endoscopic instruments), delineation of the resection extent (ioMRI, ioUS, and fluorescence), and intraoperative safety (neurophysiological monitoring, ioMRI). This article discusses the aforementioned technological advances, and their multimodal use to optimize safe pediatric neuro-oncology surgery.