Applying Convolutional Neural Networks to Neuroimaging Classification Tasks: A Practical Guide in Python.

In this chapter, we describe the process of obtaining medical imaging data and its storage protocol. The authors also explain in a step-by-step approach how to extract and prepare the medical imaging data for machine learning algorithms. And finally, the process of building and assessing a convolutional neural network for medical imaging data is illustrated.

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.

Encephaloduroateriosynangiosis (EDAS) in the management of Moyamoya syndrome in children with sickle cell disease.

BACKGROUND: Encephalo-duro-arterio-synangiosis (EDAS) in Moyamoya syndrome (MMS) treatment has been well described in the literature, however in MMS caused by sickle cell anaemia (SCA), EDAS use remains controversial with poor long-term follow-up. We present a case-series of SCA patients who have undergone EDAS for SCA-related MMS and describe their post-operative course as well as provide a literature review of the role of EDAS in the treatment of sickle cell anaemia. METHODS: A retrospective review of all the paediatric EDAS procedures conducted in our institution for SCA from 2007 to 2015. Two patients underwent behavioural screening. RESULTS: A total of eight patients with MMS secondary to SCA underwent EDAS. Unilateral EDAS was performed without complication in seven patients. One patient underwent bilateral EDAS but with a two-year gap in between procedures. Follow-up magnetic resonance angiography demonstrated no progression of Moyamoya collaterals or further ischaemic events with regression of collaterals clearly visible in one patient. All patients have demonstrated a return to normal school activities. CONCLUSIONS: EDAS is a well-tolerated revascularisation procedure for children with MMS. The prevention of further infarcts in our group with sickle cell disease has allowed these children to resume normal school activities.

The evolution of British neurosurgical selection and training over the past decade.

Selection of junior doctors into the British neurosurgical training program and subsequent speciality training have undergone several key changes over the past decade. Shift patterns in the era of the European Working Time Directive (EWTD) have had a major impact on surgical training. We discuss the national selection process, formalization of surgical simulation training and the need to encompass generic professional capabilities within the neurosurgical curriculum in order to create the "well-rounded surgeon". Future directions including hybrid cerebrovascular training, training in stereotactic radiosurgery, and dedicated training opportunities in spinal surgery.

Anti-Coagulation and Deep Brain Stimulation: Never the Twain Shall Meet.

Deep brain stimulation (DBS) for movement disorders is usually performed in older patients who may be prone to vascular co-morbidities such as atrial fibrillation or valvular disease that may require anti-coagulation. This potentially increases the risk of peri-operative intra-cranial haemorrhage and thus anti-coagulation therapy is generally considered a contraindication for DBS implantation. Cessation of anti-coagulants has to be balanced with the risk of thrombosis or ischaemic complications and, to compound issues, there is a paucity of guidelines and consensus on the management of anti-coagulation in patients undergoing DBS. To date, we have performed DBS successfully in 4 patients on lifelong anti-coagulation, having carefully managed their anti-coagulation in the peri-operative period. One patient developed a moderate haematoma around the implantable pulse generator 2 days post-operatively that was treated conservatively. Otherwise no other adverse effects or haemorrhagic complications occurred. We therefore propose that DBS implantation in this group of patients is safe, provided strict observation of protocols and careful management of the anti-coagulation therapy are undertaken. We describe the indications for anti-coagulation and provide a guideline for therapy in such patients according to our experience.

Moyamoya angiopathy - Is there a Western phenotype?

Moyamoya disease (MMD) is a chronic cerebrovascular disease involving progressive bilateral stenosis of the intracranial segments of the internal carotid arteries. It results in the development of a rich, but friable collateral supply, prone to rupture. The disease is well described in Japanese literature and was originally thought to be a predozminantly Eastern disease. However, the recent literature describes a Western phenotype that may present with a different clinical course. This review aims to describe the variations in the epidemiology of the MMD between Eastern and Western populations, the possible reasons for them and highlight their implications for clinical practise and future research.

Deep brain stimulation of the subthalamic nucleus in Parkinson's disease 2003-2013: Where are we another 10 years on?

High-frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) is now ending its second decade as an established modality for treating Parkinson's disease (PD). Knowledge of the pathophysiology of PD and clinical applications for STN DBS is burgeoning. Despite this, the mechanism of how STN DBS works remains an enigma. Furthermore, motor symptoms have been seen as a focus for improved quality of life after STN DBS yet non-motor symptoms also play an integral role in determining treatment outcome. In this paper, new evidence for the mechanisms of action of STN DBS is discussed and the impact of the therapy on motor and non-motor symptoms of PD is analysed. Future directions of treatment and emerging technologies are also reviewed.

Reducing the Gap in Neurosurgical Education in LMICs: A Report of a Non-Profit Educational Program.

INTRODUCTION: Central to neurosurgical care, neurosurgical education is particularly needed in low- and middle-income countries (LMICs), where opportunities for neurosurgical training are limited due to social and economic constraints and an inadequate workforce. The present paper aims (1) to evaluate the validity and usability of a cadaver-free hybrid system in the context of LMICs and (2) to report their learning needs and whether the courses meet those needs via a comprehensive survey. METHODS: From April to November 2021, a non-profit initiative consisting of a series of innovative cadaver-free courses based on virtual and practical training was organized. This project emerged from a collaboration between the Young Neurosurgeons Forum of the World Federation of Neurological Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and UpSurgeOn, an Italian hi-tech company specialized in simulation technologies, creator of the UpSurgeOn Box, a hyper-realistic simulator of cranial approaches fused with augmented reality. Over that period, 11 cadaver-free courses were held in LMICs using remote hands-on Box simulators. RESULTS: One hundred sixty-eight participants completed an online survey after course completion of the course. The anatomical accuracy of simulators was overall rated high by the participant. The simulator provided a challenging but manageable learning curve, and 86% of participants found the Box to be very intuitive to use. When asked if the sequence of mental training (app), hybrid training (Augmented Reality), and manual training (the Box) was an effective method of training to fill the gap between theoretical knowledge and practice on a real patient/cadaver, 83% of participants agreed. Overall, the hands-on activities on the simulators have been satisfactory, as well as the integration between physical and digital simulation. CONCLUSIONS: This project demonstrated that a cadaver-free hybrid (virtual/hands-on) training system could potentially participate in accelerating the learning curve of neurosurgical residents, especially in the setting of limited training possibilities such as LMICs, which were only worsened during the COVID-19 pandemic.

Neurosurgical interventions for cancer pain.

PURPOSE OF REVIEW: Half of all cancer patients will develop cancer-related pain, and a fifth of these patients will continue to experience pain refractory to maximal pharmacological therapy. This, together with the opioid crisis, has prompted a resurgence in neurosurgical treatments. Neuromodulatory or neuroablative procedures are largely used for various nonmalignant, chronic pain conditions, but there is growing evidence to support their use in cancer pain. This review aims to cover the main neurosurgical treatments that may prove useful in the changing sphere of cancer pain treatment. RECENT FINDINGS: Neuromodulation techniques for pain have largely replaced neuroablation in neurosurgical practice due to the higher risk of inadvertent permanent neurological deficits from the latter. When compared to neuroablative approaches for severe treatment-refractory cancer pain, neuromodulation is more expensive (largely due to implant cost) and requires more follow-up, with greater engagement needed from the health service, the patient and their carers. Furthermore, neuroablation has a more rapid onset of effect. SUMMARY: Neuromodulation techniques for pain have largely replaced neuroablation in neurosurgical practice due to the higher risk of inadvertent permanent neurological deficits from the latter. Whilst this approach is beneficial when treating nonmalignant pain, neuromodulation in patients with pain related to advanced cancer still has a limited role. Neuroablative procedures are less expensive, require less follow-up, and can have a lower burden on health services, patients and their carers.

Factors Influencing Surgical Decision-Making in the Posterior Laminectomy With Fixation for Degenerative Cervical Myelopathy (POLYFIX-DCM) Trial: Survey Study.

BACKGROUND: Degenerative cervical myelopathy (DCM) is estimated to affect 2% of the adult population. DCM occurs when degenerative processes cause compression and injure the spinal cord. Surgery to remove the stress caused by the compression of the spinal cord is the mainstay of treatment, with a range of techniques in use. Although various factors are described to inform the selection of these techniques, there needs to be more consensus and limited comparative evidence. OBJECTIVE: The main objective of this survey was to explore the variation of practice and decision-making, with a focus on laminectomy versus laminectomy and fusion in posterior surgery of the cervical spine. We present the results of a survey conducted among the principal investigators (PIs) of the National Institute for Health and Care Research (NIHR) randomized controlled trial on posterior laminectomy with fixation for degenerative cervical myelopathy (POLYFIX-DCM). METHODS: A series of 7 cases were shared with 24 PIs using SurveyMonkey. Each case consisted of a midsagittal T2-weighted magnetic resonance imaging and lateral cervical x-rays in flexion and extension. Surgeons were asked if their preferred approach was anterior or posterior. If posterior, they were asked whether they preferred to instrument and whether they had the equipoise to randomize in the NIHR POLYFIX-DCM trial. Variability in decision-making was then explored using factors reported to inform decision-making, such as alignment, location of compression, number of levels operated, presence of mobile spondylolisthesis, and patient age. RESULTS: The majority of PIs (16/30, 53%) completed the survey. Overall, PIs favored a posterior approach (12/16, 75%) with instrumentation (75/112, average 66%) and would randomize (67/112, average 62%) most cases. Factors reported to inform decision-making poorly explained variability in responses in both univariate testing and with a multivariate model (R2=0.1). Only surgeon experience of more than 5 years and orthopedic specialty training background were significant predictors, both associated with an anterior approach (odds ratio [OR] 1.255; P=.02 and OR 1.344; P=.007, respectively) and fusion for posterior procedures (OR 0.628; P<.001 and OR 1.344; P<.001, respectively). Surgeon experience also significantly affected the openness to randomize, with those with more than 5 years of experience less likely to randomize (OR -0.68; P<.001). CONCLUSIONS: In this representative sample of spine surgeons participating in the POLYFIX-DCM trial as investigators, there is no consensus on surgical strategy, including the role of instrumented fusion following posterior decompression. Overall, this study supports the view that there appears to be a clinical equipoise, and conceptually, a randomized controlled trial appears feasible, which sets the scene for the NIHR POLYFIX-DCM trial.

Deep Brain Stimulation for Chronic Pain.

Deep brain stimulation (DBS) is a neurosurgical intervention well known for the treatment of movement disorders as well as epilepsy, Tourette syndrome, and obsessive-compulsive disorders. DBS was pioneered in the 1950s, however, as a tool for treating facial pain, phantom limb pain, post-stroke pain, and brachial plexus pain among other disease states. Various anatomic targets exist, including the sensory thalamus (ventral posterior lateral and ventral posterior medial), the periaqueductal gray and periventricular gray matter, and the anterior cingulate cortex.

Sir Victor Horsley (1857-1916): lessons for the modern clinician.

Sir Victor Horsley is well known for his pioneering work as a neurological surgeon but his vital contributions to the regulation and advancement of the medical profession are less well understood. This archived literature review of The Horsley collection of papers (UCL Special Collections Library) documents Sir Victor's campaign for the autonomy of the stagnating medical profession of over a century ago. These lessons should empower modern clinicians to retain the professionalism they worry about losing.

"It's not rocket science" and "It's not brain surgery"-"It's a walk in the park": prospective comparative study.

OBJECTIVE: To compare cognitive testing scores in neurosurgeons and aerospace engineers to help settle the age old argument of which phrase-"It's not brain surgery" or "It's not rocket science"-is most deserved. DESIGN: International prospective comparative study. SETTING: United Kingdom, Europe, the United States, and Canada. PARTICIPANTS: 748 people (600 aerospace engineers and 148 neurosurgeons). After data cleaning, 401 complete datasets were included in the final analysis (329 aerospace engineers and 72 neurosurgeons). MAIN OUTCOME MEASURES: Validated online test (Cognitron's Great British Intelligence Test) measuring distinct aspects of cognition, spanning planning and reasoning, working memory, attention, and emotion processing abilities. RESULTS: The neurosurgeons showed significantly higher scores than the aerospace engineers in semantic problem solving (difference 0.33, 95% confidence interval 0.13 to 0.52). Aerospace engineers showed significantly higher scores in mental manipulation and attention (-0.29, -0.48 to -0.09). No difference was found between groups in domain scores for memory (-0.18, -0.40 to 0.03), spatial problem solving (-0.19, -0.39 to 0.01), problem solving speed (0.03, -0.20 to 0.25), and memory recall speed (0.12, -0.10 to 0.35). When each group's scores for the six domains were compared with those in the general population, only two differences were significant: the neurosurgeons' problem solving speed was quicker (mean z score 0.24, 95% confidence interval 0.07 to 0.41) and their memory recall speed was slower (-0.19, -0.34 to -0.04). CONCLUSIONS: In situations that do not require rapid problem solving, it might be more correct to use the phrase "It's not brain surgery." It is possible that both neurosurgeons and aerospace engineers are unnecessarily placed on a pedestal and that "It's a walk in the park" or another phrase unrelated to careers might be more appropriate. Other specialties might deserve to be on that pedestal, and future work should aim to determine the most deserving profession.

Improving Neurosurgery Education Using Social Media Case-Based Discussions: A Pilot Study.

BACKGROUND: The increasing shift toward a more generalized medical undergraduate curriculum has led to limited exposure to subspecialties, including neurosurgery. The lack of standardized teaching may result in insufficient coverage of core learning outcomes. Social media (SoMe) in medical education are becoming an increasingly accepted and popular way for students to meet learning objectives outside formal medical school teaching. We delivered a series of case-based discussions (CbDs) over SoMe to attempt to meet core learning needs in neurosurgery and determine whether SoMe-based CbDs were an acceptable method of education. METHODS: Twitter was used as a medium to host 9 CbDs pertaining to common neurosurgical conditions in practice. A sequence of informative and interactive tweets were formulated before live CbDs and tweeted in progressive order. Demographic data and participant feedback were collected. RESULTS: A total of 277 participants were recorded across 9 CbDs, with 654,584 impressions generated. Feedback responses were received from 135 participants (48.7%). Participants indicated an increase of 77% in their level of knowledge after participating. Of participants, 57% (n = 77) had previous CbD experience as part of traditional medical education, with 62% (n = 84) receiving a form of medical education previously through SoMe. All participants believed that the CbDs objectives were met and would attend future sessions. Of participants, 99% (n = 134) indicated that their expectations were met. CONCLUSIONS: SoMe has been shown to be a favorable and feasible medium to host live, text-based interactive CbDs. SoMe is a useful tool for teaching undergraduate neurosurgery and is easily translatable to all domains of medicine and surgery.

Neurosurgery Education in the Medical School Curriculum: A Scoping Review.

OBJECTIVE: Despite a high burden of neurosurgical disease that is often assessed, investigated, and managed by generalists, to our knowledge, there is no specific medical school curriculum in neurosurgery. This scoping review was carried out to map available evidence pertaining to the provision of neurosurgery education in the medical school curriculum across the world. METHODS: This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews. Inclusion criteria were full-text articles reported from 1999 onward, which reported on neurosurgery education in the medical curriculum. RESULTS: Ten studies were included. Six were from the United Kingdom, 2 from the United States, and 1 each from Canada and Ireland. Seven studies reported perceptions of medical students and 5 reported perceptions of clinicians. Three main themes were identified. Neurosurgery was perceived as an important part of the general medical student curriculum by students and neurosurgeons but less so by medical school deans. Exposure to neurosurgery teaching was varied but, when received, deemed useful and students were keen to receive more. Interest in a neurosurgical career among surveyed medical students was high. CONCLUSIONS: The limited evidence has shown variability of perceptions about the importance of neurosurgery among stakeholders and medical students' exposure to neurosurgery teaching. Our findings highlight the need to systematically assess specialty-specific teaching and determine adequacy. Stakeholders should include neurosurgeons, medical educators, general practitioners, and the variety of specialists who play a crucial role in the management of patients with neurosurgical conditions.

The Exoscope versus operating microscope in microvascular surgery: A simulation non-inferiority trial.

BACKGROUND: The Exoscope is a novel high-definition digital camera system. There is limited evidence signifying the use of exoscopic devices in microsurgery. This trial objectively assesses the effects of the use of the Exoscope as an alternative to the standard operating microscope (OM) on the performance of experts in a simulated microvascular anastomosis. METHODS: Modus V Exoscope and OM were used by expert microsurgeons to perform standardized tasks. Hand-motion analyzer measured the total pathlength (TP), total movements (TM), total time (TT), and quality of end-product anastomosis. A clinical margin of TT was performed to prove non-inferiority. An expert performed consecutive microvascular anastomoses to provide the exoscopic learning curve until reached plateau in TT. RESULTS: Ten micro sutures and 10 anastomoses were performed. Analysis demonstrated statistically significant differences in performing micro sutures for TP, TM, and TT. There was statistical significance in TM and TT, however, marginal non-significant difference in TP regarding microvascular anastomoses performance. The intimal suture line analysis demonstrated no statistically significant differences. Non-inferiority results based on clinical inferiority margin (Δ) of TT=10 minutes demonstrated an absolute difference of 0.07 minutes between OM and Exoscope cohorts. A 51%, 58%, and 46% improvement or reduction was achieved in TT, TM, TP, respectively, during the exoscopic microvascular anastomosis learning curve. CONCLUSIONS: This study demonstrated that experts' Exoscope anastomoses appear non-inferior to the OM anastomoses. Exoscopic microvascular anastomosis was more time consuming but end-product (patency) in not clinically inferior. Experts' "warm-up" learning curve is steep but swift and may prove to reach clinical equality.

The World Federation of Neurosurgical Societies Young Neurosurgeons Survey (Part I): Demographics, Resources, and Education.

BACKGROUND: Providing a comprehensive and effective neurosurgical service requires adequate numbers of well-trained, resourced, and motivated neurosurgeons. The survey aims to better understand 1) the demographics of young neurosurgeons worldwide; 2) the challenges in training and resources that they face; 3) perceived barriers; and 4) needs for development. METHODS: This was a cross-sectional study in which a widely disseminated online survey (April 2018-November 2019) was used to procure a nonprobabilistic sample from current neurosurgical trainees and those within 10 years of training. Data were grouped by World Bank income classifications and analyzed using χ2 tests because of its categorical nature. RESULTS: There were 1294 respondents, with 953 completed responses included in the analysis. Of respondents, 45.2% were from high-income countries (HICs), 23.2% from upper-middle-income countries, 26.8% lower-middle-income countries, and 4.1% from low-income countries. Most respondents (79.8%) were male, a figure more pronounced in lower-income groups. Neuro-oncology was the most popular in HICs and spinal surgery in all other groups. Although access to computed tomography scanning was near universal (98.64%), magnetic resonance imaging access decreased to 66.67% in low-income countries, compared with 98.61% in HICs. Similar patterns were noted with access to operating microscopes, image guidance systems, and high-speed drills. Of respondents, 71.4% had dedicated time for neurosurgical education. CONCLUSIONS: These data confirm and quantify disparities in the equipment and training opportunities among young neurosurgeons practicing in different income groups. We hope that this study will act as a guide to further understand these differences and target resources to remedy them.

The World Federation of Neurosurgical Societies Young Neurosurgeons Survey (Part II): Barriers to Professional Development and Service Delivery in Neurosurgery.

BACKGROUND: Strengthening health systems requires attention to workforce, training needs, and barriers to service delivery. The World Federation of Neurosurgical Societies Young Neurosurgeons Committee survey sought to identify challenges for residents, fellows, and consultants within 10 years of training. METHODS: An online survey was distributed to various neurosurgical societies, personal contacts, and social media platforms (April-November 2018). Responses were grouped by World Bank income classification into high-income countries (HICs), upper middle-income countries (UMICs), low-middle-income countries (LMICs), and low-income countries (LICs). Descriptive statistical analysis was performed. RESULTS: In total, 953 individuals completed the survey. For service delivery, the limited number of trained neurosurgeons was seen as a barrier for 12.5%, 29.8%, 69.2%, and 23.9% of respondents from HICs, UMICs, LMICs, and LICs, respectively (P < 0.0001). The most reported personal challenge was the lack of opportunities for research (HICs, 34.6%; UMICs, 57.5%; LMICs, 61.6%; and LICs, 61.5%; P = 0.03). Other differences by income class included limited access to advice from experienced/senior colleagues (P < 0.001), neurosurgical journals (P < 0.0001), and textbooks (P = 0.02). Assessing how the World Federation of Neurosurgical Societies could best help young neurosurgeons, the most frequent requests (n = 953; 1673 requests) were research (n = 384), education (n = 296), and subspecialty/fellowship training (n = 232). Skills courses and access to cadaver dissection laboratories were also heavily requested. CONCLUSIONS: Young neurosurgeons perceived that additional neurosurgeons are needed globally, especially in LICs and LMICs, and primarily requested additional resources for research and subspecialty training.