Knowledge Of Neuroanatomy Research Articles

Advancements in Brain Aneurysm Management: Integrating Neuroanatomy, Physiopathology, and Neurosurgical Techniques.

Brain aneurysms, characterized by abnormal bulging in blood vessels, pose significant risks if ruptured, necessitating precise neuroanatomical knowledge and advanced neurosurgical techniques for effective management. This article delves into the intricate neuroanatomy relevant to brain aneurysms, including the vascular structures and critical regions involved. It provides a comprehensive overview of the pathophysiology of aneurysm formation and progression. The discussion extends to modern neurosurgical approaches for treating brain aneurysms, such as microsurgical clipping, endovascular coiling, and flow diversion techniques. Emphasis is placed on preoperative planning, intraoperative navigation, and postoperative care, highlighting the importance of a multidisciplinary approach. By integrating neuroanatomical insights with cutting-edge surgical practices, this article aims to enhance the understanding and treatment outcomes of brain aneurysms.

A next-generation, histological atlas of the human brain and its application to automated brain MRI segmentation.

Magnetic resonance imaging (MRI) is the standard tool to image the human brain in vivo. In this domain, digital brain atlases are essential for subject-specific segmentation of anatomical regions of interest (ROIs) and spatial comparison of neuroanatomy from different subjects in a common coordinate frame. High-resolution, digital atlases derived from histology (e.g., Allen atlas [7], BigBrain [13], Julich [15]), are currently the state of the art and provide exquisite 3D cytoarchitectural maps, but lack probabilistic labels throughout the whole brain. Here we present NextBrain, a next-generation probabilistic atlas of human brain anatomy built from serial 3D histology and corresponding highly granular delineations of five whole brain hemispheres. We developed AI techniques to align and reconstruct ~10,000 histological sections into coherent 3D volumes with joint geometric constraints (no overlap or gaps between sections), as well as to semi-automatically trace the boundaries of 333 distinct anatomical ROIs on all these sections. Comprehensive delineation on multiple cases enabled us to build the first probabilistic histological atlas of the whole human brain. Further, we created a companion Bayesian tool for automated segmentation of the 333 ROIs in any in vivo or ex vivo brain MRI scan using the NextBrain atlas. We showcase two applications of the atlas: automated segmentation of ultra-high-resolution ex vivo MRI and volumetric analysis of Alzheimer's disease and healthy brain ageing based on ~4,000 publicly available in vivo MRI scans. We publicly release: the raw and aligned data (including an online visualisation tool); the probabilistic atlas; the segmentation tool; and ground truth delineations for a 100 μm isotropic ex vivo hemisphere (that we use for quantitative evaluation of our segmentation method in this paper). By enabling researchers worldwide to analyse brain MRI scans at a superior level of granularity without manual effort or highly specific neuroanatomical knowledge, NextBrain holds promise to increase the specificity of MRI findings and ultimately accelerate our quest to understand the human brain in health and disease.

Pilot Program in Surgical Anatomy Education for Complex Cranial and Skull Base Procedures: Curriculum Overview and Initial 2-Year Experience at Mayo Clinic

Abstract Background Cadaveric dissection remains a preferred and irreplaceable learning modality among neurosurgery residents. We aimed to develop and describe a tiered, quantifiable, and practical curriculum for cranial neurosurgical anatomy education. We report the structure and evaluation of our 2-year pilot study to serve as a suggested guide for other neurosurgery programs. Methods Our Complex Cranial Dissection Program is tailored to the needs of junior-level neurosurgery residents based on their postgraduation years 1 to 4. Dissections are performed in a sequential manner, each of which emphasize a particular set of manual skills and neuroanatomical knowledge. Dissections are scored on a scale of 10 points. The grading was based on specific landmarks and anatomical structures, which need to be exposed, explored, and preserved. Results Out of 16 residents, 14 individuals (87.5%) attended the dissections in the first iteration of the program and 16 individuals (100%) attended the dissections in the second iteration. A total of 17 dissections were performed across all years. In survey feedback about the program, 100% (Year 1) and 94% (Year 2) of residents considered the assigned dissections to be appropriate for their respective training levels. Further, 100% (Year 1) and 94% (Year 2) of residents endorsed that the dissections were important and helpful for their practice prior to similar operating room experiences. Conclusion The development and implementation of structured dissection programs within residency training, along with dedicated staff, and objective feedback serve a crucial role in neurosurgical education to further develop and enhance surgical skills in the operative setting.

Effects of a Novelty Virtual Interactive Brain Atlas on Student Perception of Neuroanatomy

The instructional techniques in neuroanatomy laboratories continue to evolve to incorporate online interactive resources to improve student experience and outcomes. This study aims to design an “all in one”Virtual Interactive Brain Atlas (VIBA) that provides students with an educational resource that will improve their knowledge of neuroanatomy while in the brain lab and provide them with lab resources they can self-study and self-test. Coronal, midsagittal, whole brain, and horizontal brain slices were used to create detailed descriptions, interactive features, and quiz assessments to create VIBA. Upper level undergraduate and optometry students taking a neuroanatomy one-semester course were provided with VIBA for use during the semester. A paper survey was distributed after completing the course to determine student perception. No significant difference was indicated between the student groups regarding their self-reported understanding prior to the brain lab (p= 0.194) and after the brain lab (p= 0.308). There was a significant difference between the student populations when stating that they strongly agreed that the online brain atlas improved their understanding of neuroanatomy (p= 0.032) and that the VIBA tool was easy to navigate (p=0.048). There was a significant difference between the two student groups that strongly agreed that the online brain atlas quality was sufficient (p= 0.015). This online interactive brain atlas was created in a time-efficient manner from readily available models and was well received by experienced neuroanatomy faculty and students.

A Narrative Review on the Clinical Relevance of Imaging the Circumventricular Brain Organs and Performing Their Anatomical and Histopathological Examination in Acute and Postacute COVID-19.

Autopsy followed by histopathological examination is foundational in clinical and forensic medicine for discovering and understanding pathological changes in disease, their underlying processes, and cause of death. Imaging technology has become increasingly important for advancing clinical research and practice, given its noninvasive, in vivo and ex vivo applicability. Medical and forensic autopsy can benefit greatly from advances in imaging technology that lead toward minimally invasive, whole-brain virtual autopsy. Brain autopsy followed by histopathological examination is still the hallmark for understanding disease and a fundamental modus operandi in forensic pathology and forensic medicine, despite the fact that its practice has become progressively less frequent in medical settings. This situation is especially relevant with respect to new diseases such as COVID-19 caused by the SARS-CoV-2 virus, for which our neuroanatomical knowledge is sparse. In this narrative review, we show that ad hoc clinical autopsies and histopathological analyses combined with neuroimaging of the principal circumventricular organs are critical to gaining insight into the reconstruction of the pathophysiological mechanisms and the explanation of cause of death (ie, atrium mortis) related to the cardiovascular effects of SARS-CoV-2 infection in forensic and clinical medicine.

Shoulder terminal sensory articular nerve radiofrequency ablation for nonsurgical refractory shoulder pain due to rotator cuff pathology and osteoarthritis: a technical note.

Given the high prevalence of chronic shoulder pain and encouraging early results of terminal sensory articular branch radiofrequency ablation to treat shoulder pain, research is warranted to refine the procedural technique on the basis of updated neuroanatomic knowledge with the goal of further improving patient outcomes. We describe an updated radiofrequency ablation protocol that accounts for varied locations of the terminal sensory articular branches of the suprascapular, axillary, subscapular, and lateral pectoral nerves within individual patients. Technical note. Cadaveric studies delineating the sensory innervation of the shoulder joint were reviewed, and a more comprehensive radiofrequency ablation protocol is proposed relative to historical descriptions. The proposed radiofrequency ablation protocol, which is based on neuroanatomic dissections of the shoulder joint, will provide a safe means of more complete sensory denervation and potentially improve clinical outcomes compared with historical descriptions, the efficacy of the new protocol must be confirmed in prospective studies.

Accuracy of ChatGPT in Neurolocalization.

Introduction ChatGPT (OpenAI Incorporated, Mission District, San Francisco, United States)is an artificial intelligence (AI) chatbot with advanced communication skills and a massive knowledge database. However, its application in medicine, specifically in neurolocalization, necessitates clinical reasoning in addition to deep neuroanatomical knowledge. This article examines ChatGPT's capabilities in neurolocalization. Methods Forty-six text-based neurolocalization case scenarios were presented to ChatGPT-3.5 from November 6th, 2023, to November 16th, 2023. Seven neurosurgeons evaluated ChatGPT's responses to these cases, utilizing a 5-point scoring system recommended by ChatGPT, to score the accuracy of these responses. Results ChatGPT-3.5 achieved an accuracy score of 84.8% in generating "completely correct" and "mostly correct" responses. ANOVA analysis suggested a consistent scoring approach between different evaluators. The mean length of the case text was 69.8 tokens (SD 20.8). Conclusion While this accuracy score is promising, it is not yet reliable for routine patient care. We recommend keeping interactions with ChatGPT concise, precise, and simple to improve response accuracy. As AI continues to evolve, it will hold significant and innovative breakthroughs in medicine.

Students' perspectives regarding needs for and opportunities with mixed-reality education in neurosurgery at German medical schools.

Despite mixed reality being an emerging tool for tailored neurosurgical treatment and safety enhancement, the use of mixed reality in the education of German medical students is not established in the field of neurosurgery. The present study aimed to investigate medical students' perspectives on the use of mixed reality in neurosurgical medical education. Between July 3, 2023, and August 31, 2023, an online survey was completed by German medical students through their affiliated student associations and educational institutions. The survey included 16 items related to mixed reality in neurosurgery, with participants providing ratings on a 4-point Likert scale to indicate their level of agreement with these statements. A total of 150 students from 27 medical schools in Germany took part in the survey. A significant majority comprising 131 (87.3%) students expressed strong to intense interest in mixed-reality courses in neurosurgery, and 108 (72%) reported an interest in incorporating mixed reality into their curriculum. Furthermore, 94.7% agreed that mixed reality may enhance their understanding of operative neuroanatomy and 72.7% agreed with the idea that teaching via mixed-reality methods may increase the probability of the use of mixed reality in their future career. The majority (116/150 [77.3%]) reported that the preferred optimum timepoint for teaching with mixed reality might be within the first 3 years of medical school. In particular, more students in the first 2 years preferred to start mixed-reality courses in the first 2 years of medical school compared to students in their 3rd to 6th years of medical school (71.9% vs 41.5%, p = 0.003). Residents and attending specialists were believed to be appropriate teachers by 118 students (78.7%). German medical students exhibited significant interest and willingness to engage in mixed reality in neurosurgery. Evidently, there is a high demand for medical schools to provide mixed-reality courses. Students seem to prefer the courses as early as possible in their medical school education in order to transfer preclinical neuroanatomical knowledge into operative neurosurgical anatomy by using this promising technique.

A Know-Brainer: The Power of Cadaver-Based Instruction to Teach Clinical Neuroanatomy.

Learning experiences that incorporate cadaver prosection or dissection of the brain have shown to enhance the acquisition and retention of neuroanatomy and improve standardized examination scores when included within medical curriculum. However, the role of cadaver-based instruction within allied health fields, and particularly in the field of communication sciences and disorders (CSD), remains limited and less understood. The effectiveness of a cadaver-based lab compared to lecture to teach neuroanatomy within an undergraduate/postbaccalaureate clinical neuroscience course for CSD majors was explored within a crossover design. Fifty-four participants were stratified by class rank between two initial training sessions: lab-first versus lecture-first. Neuroanatomical knowledge was tested via labeling tasks at baseline, after the first allocated training, and at 1-week follow-up after crossover training had been completed. Both cohorts demonstrated significant gains in neuroanatomical knowledge following training, yet after the initial training session, students that received cadaver-based instruction produced a significantly greater number (p < .001) and more accurate (p < .001) anatomical labels than students that received lecture. After completion of the crossover design, students receiving cadaver-based instruction prior to lecture continued to demonstrate superior labeling accuracy at follow-up testing (p = .022). Cadaver-based instruction was more effective in improving students' ability to identify neuroanatomy compared to lecture for CSD students. Interestingly, cadaver-based demonstrations were also most effective in bolstering students' retention of structural knowledge when conducted before, instead of after, a lecture. Clinical training programs, specifically student learning outcomes, benefit from cadaver-based instruction that provides both three-dimensional orientation and a deep appreciation of the human elements of clinical anatomy. Furthermore, both the acquisition and retention of anatomical concepts may be enhanced through strategic instructional design, particularly in regard to the order of lecture and lab experiences.

Knowledge, Practice and Self-Reported Confidence Level of Croatian Dentists in the Use of Local Anesthesia: A Cross-Sectional Study.

Objectives: To provide safe and effective local anesthesia, dentists must have knowledge of neuroanatomy, anesthesia agents, techniques, equipment, and proper use of local anesthetics. This study aims to explore the knowledge, practices, and confidence regarding local anesthetics and anesthetic techniques in dentistry. Material and Methods: The online cross-sectional questionnaire was conducted via social media, and yielded 441 responses from across the country (69.8% women and 30.2% men; 70.7% general dentists; and 29.3 specialists). The data collected included sociodemographic characteristics, knowledge, and practices pertaining to the usage of local anesthesia. The questionnaire also documents their self-assessed confidence level in applying different local anesthetic techniques and experiences with adverse reactions. The obtained data were processed by description and using a generalized linear model for regression. Results: The respondents had a median knowledge score of 6 out of a possible 14 points regarding local anesthetics in dental medicine, and their median self-confidence level in the successful application of various techniques of local anesthesia was 54 out of a maximum of 85 points. The results showed that a higher knowledge level was associated with the female gender (OR 1.83, CI 1.13-2.98, p = 0.014) and specialization in oral surgery (OR 7.04, CI 1.71-29.07, p = 0.007). In contrast, a lack of confidence in using various local anesthetic techniques was also associated with the female gender (OR 0.63, CI 0.41-0.99, p = 0.047) and specialization in orthodontics (OR 0.16, CI 0.03-0.88, p = 0.035). Of the respondents, 81.4% (n = 371) experienced a local complication, and 42.2% (n = 186) experienced a systemic complication during local anesthesia. The complications experienced cannot be associated with a lack of knowledge or self-confidence (p > 0.05). The majority of respondents (364 of the 441 total-82.5%) expressed interest in receiving further education on the topic of local anesthesia. Conclusions: The research results show that the dentists involved in the study have poor knowledge of local anesthetics and moderate self-reported confidence levels in using various local anesthetic techniques. Moreover, dentists' self-confidence in applying different techniques of local anesthesia is not related to their knowledge. Therefore, it would be necessary for dentists to undergo a continuing dental education program that enables them to enhance their skills and knowledge in local anesthesia.

Photo-Stacking Technique for Neuroanatomical High-Definition Photography and 3-Dimensional Modeling

Three-dimensional (3D) neuroanatomical knowledge is vital in neurosurgery. Technological advances improved 3D anatomical perception, but they are usually expensive and not widely available. The aim of the present study was to provide a detailed description of the photo-stacking technique for high-resolution neuroanatomical photography and 3D modeling. The photo-stacking technique was described in a step-by-step approach. The time for image acquisition, file conversion, processing, and final production was measured using 2 processing methods. The total number and file size of images are presented. Measures of central tendency and dispersion report the measured values. Ten models were used in both methods achieving 20 models with high-definition images. The mean number of acquired images was 40.6 (14-67), image acquisition time 51.50±18.8 s, file conversion time 250±134.6s, processing time 50.46±21.46s and 41.97±20.84s, and 3D reconstruction time was 4.29±0.74s and 3.89±0.60s for methods B and C, respectively. The mean file size of RAW files is 1010±452megabyte (MB) and 101.06±38.09MB for Joint Photographic Experts Group files after conversion. The mean size of the final image means size is 71.9±0.126MB, and the mean file size of the 3D model means is 37.4±0.516MB for both methods. The total equipment used was less expensive than other reported systems. The photo-stacking technique is a simple and inexpensive method to create 3D models and high-definition images that could prove valuable in neuroanatomy training.

Assessing the impact of neurosurgery and neuroanatomy simulation using 3D non-cadaveric models amongst selected African medical students.

Laboratory dissections are essential to acquire practical skills to perform neurosurgical procedures. Despite being traditionally done on cadavers, they are often unavailable and suffer from cultural barriers in the African context. Non-cadaveric UpSurgeOn neurosurgery models have been developed to bridge this barrier, providing an almost similar experience with the human body. This study aimed to assess the impact of the UpSurgeOn hands-on-touch non-cadaver model training amongst selected Cameroon medical students. An anonymous 35-item questionnaire was distributed online using Google drive systems to medical students who attended UpSurgeOn's hands-on-touch non-cadaver model training course. These questions aimed to capture data on previous experience with neuroanatomy and neurosurgery practicals and the perception, attitudes, and impact of the UpSurgeOn neurosurgery tool. Eighty-six students completed the survey. The mean age was 21.2 ± 1.868 years, 61.6% were males with 62.8% of respondents being medical students in preclinical years. Before the training, 29.4% had a fair knowledge of neuroanatomy. Textbooks and Youtube videos were the main sources of neuroanatomy and neurosurgery knowledge for more than half of the respondents. Up to 91.5% had no prior exposure to a neuroanatomy/neurosurgery cadaver laboratory dissection, and 22.6% and 17.6% had witnessed and performed at least one craniotomy before, respectively. There were 11.1%, 15.5%, and 31.3% of our respondents who had used a surgical microscope, a neurosurgical instrument, and the UpSurgeOn Neurosurgery tool before, respectively. The majority perceived the UpSurgeOn tool easy to use and felt they needed to learn just a few things before getting going with the box. Most thought of increasing the use of the UpSurgeOn Box and saw the need to be part of the training curriculum. Finally, the majority felt this tool helped to increase familiarity and acquire neurosurgical skills, and to develop the orientation skills needed during neurosurgical approaches. Undergraduate exposure to traditional neurosurgery/neuroanatomy labs is limited in Cameroon. Neurosurgery/neuroanatomy practical skills are gained essentially using non-practical means. Most students found the UpSurgeOn tool user-friendly, saw the need to incorporate it as part of their training, and perceived it to be essential in getting acquainted with neurosurgical skills.

A novel 3D anatomical visualization system to avoid injuries of nerves in retrosigmoid approach.

The retro-sigmoid approach (RA), widely used during different neurosurgical procedures, is burdened by the risk of injuries of the nerves that cross that region contributing to possible postoperative complications. By using, anatomage table (AT), a novel 3D anatomical visualization system, we described the nerves passing through the retromastoid area including the great occipital nerve (GON), the lesser occipital nerve (LON) and the great auricular nerve (GAN), and their courses from the origins, till terminal branches. Moreover, using dedicated software, we measured distances between the nerves and well-recognizable bony landmarks. After identifying the nerves and their distances from bony landmarks, we observed that the safest and risk-free skin incision should be made in an area delimited, superiorly from the superior nuchal line (or slightly higher), and inferiorly from a plane passing at 1-1.5 cm above the mastoid tip. The lateral aspect of such an area should not exceed 9.5-10 cm from the inion, while the medial one should be more than 7 cm far from the inion. This anatomical information has been useful in defining anatomical landmarks and reducing the risk of complications, mainly related to nerve injury, in RA. In-depth neuroanatomic knowledge of the cutaneous nerves of the retromastoid area is essential to minimize the complications related to their injury during different neurosurgical approaches. Our findings suggest that the AT is a reliable tool to enhance understanding of the anatomy, and thus contributing to the refinement of surgical techniques.

Virtual endocasts of Clevosaurus brasiliensis and the tuatara: Rhynchocephalian neuroanatomy and the oldest endocranial record for Lepidosauria.

Understanding the origins of the vertebrate brain is fundamental for uncovering evolutionary patterns in neuroanatomy. Regarding extinct species, the anatomy of the brain and other soft tissues housed in endocranial spaces can be approximated by casts of these cavities (endocasts). The neuroanatomical knowledge of Rhynchocephalia, a reptilian clade exceptionally diverse in the early Mesozoic, is restricted to the brain of its only living relative, Sphenodon punctatus, and unknown for fossil species. Here, we describe the endocast and the reptilian encephalization quotient (REQ) of the Triassic rhynchocephalian Clevosaurus brasiliensis and compare it with an ontogenetic series of S. punctatus. To better understand the informative potential of endocasts in Rhynchocephalia, we also examine the brain-endocast relationship in S. punctatus. We found that the brain occupies 30% of its cavity, but the latter recovers the general shape and length of the brain. The REQ of C. brasiliensis (0.27) is much lower than S. punctatus (0.84-1.16), with the tuatara being close to the mean for non-avian reptiles. The endocast of S. punctatus is dorsoventrally flexed and becomes more elongated throughout ontogeny. The endocast of C. brasiliensis is mostly unflexed and tubular, possibly representing a more plesiomorphic anatomy in relation to S. punctatus. Given the small size of C. brasiliensis, the main differences may result from allometric and heterochronic phenomena, consistent with suggestions that S. punctatus shows peramorphic anatomy compared to Mesozoic rhynchocephalians. Our results highlight a previously undocumented anatomical diversity among rhynchocephalians and provide a framework for future neuroanatomical comparisons among lepidosaurs.

Medial Pulvinar Stimulation in Temporal Lobe Epilepsy: A Literature Review and a Hypothesis Based on Neuroanatomical Findings.

While bilateral stimulation of the anterior thalamic nuclei remains the only approved deep brain stimulation (DBS) option for focal epilepsy, two additional thalamic targets have been proposed. Earlier work indicated the potential of centromedian thalamic nucleus stimulation with recent findings highlighting the medial pulvinar nucleus. The latter has been shown to exhibit electrophysiological and imaging alterations in patients with partial status epilepticus and temporal lobe epilepsy. On this basis, recent studies have begun assessing the feasibility and efficacy of pulvinar stimulation, with encouraging results on the reduction of seizure frequency and severity. Building on existing neuroanatomical knowledge, indicating that the medial pulvinar is connected to the temporal lobe via the temporopulvinar bundle of Arnold, we hypothesize that this is one of the routes through which medial pulvinar stimulation affects temporal lobe structures. We suggest that further anatomic, imaging, and electrophysiologic studies are warranted to deepen our understanding of the subject and guide future clinical applications.

Neuroanatomy of the crocodylomorph Portugalosuchus azenhae from the late cretaceous of Portugal.

We present the first detailed braincase anatomical description and neuroanatomical study of Portugalosuchus azenhae, from the Cenomanian (Late Cretaceous) of Portugal. This eusuchian crocodylomorph was originally described as a putative Crocodylia and one of the oldest representatives of this clade; however, its phylogenetic position remains controversial. Based on new data obtained from high resolution Computed Tomography images (by micro-CT scan), this study aims to improve the original description of this taxon and also update the scarce neuroanatomical knowledge of Eusuchia and Crocodylia from this time interval, a key period to understand the origin and evolution of these clades. The resulting three-dimensional models from the CT data allowed a detailed description of its well-preserved neurocranium and internal cavities. Therefore, it was possible to reconstruct the cavities of the olfactory region, nasopharyngeal ducts, brain, nerves, carotid arteries, blood vessels, paratympanic sinus system and inner ear, which allowed to estimate some neurosensorial capabilities. By comparison with other crocodylomorphs, these analyses showed that Portugalosuchus, back in the Cenomanian, already displayed an olfactive acuity, sight, hearing and cognitive skills within the range of that observed in other basal eusuchians and crocodylians, including extant species. In addition, and in order to test its disputed phylogenetic position, these new anatomical data, which helped to correct and complete some of the original observations, were included in one of the most recent morphology-based phylogenies. The position of Portugalosuchus differs slightly from the original publication since it is now located as a "thoracosaurid" within Gavialoidea, but still as a crocodylian. Despite all this, to better contrast these results, additional phylogenetic analyses including this new morphological character coding together with DNA data should be performed.

A novel 3D surgical neuroanatomy course for medical students: Outcomes from a pilot 6-week elective

BackgroundDeveloping and maintaining a three-dimensional working knowledge of neuroanatomy is an essential skill in neurosurgery. However, conventional 2D head, neck, and neuroanatomy education is typically characterized by the separate rote learning of constituent tissues and often fails to provide learners with a contextual understanding of the relationships between these highly complex and interconnected structures. This can pose a significant challenge to medical students entering neurosurgery who lack a topographic understanding of intracranial anatomy. MethodsWe report on the design and efficacy of a novel 6-part 3D surgical neuroanatomy pilot elective for medical students that utilized a navigation-based pedagogical technique with the goal of providing students with a framework for developing a 3D mental map of the skull base, neurovasculature, ventricular system, and associated brain regions. Students took on the perspective of physically traveling along the paths of key structures with a 360-degree view of surrounding anatomy such that they could appreciate the integration and relative spatial relationships of the varying tissues within the cranium. Mental navigation exercises and pre- and post-course surveys were used to assess students’ baseline and learned familiarity with the different anatomical regions covered. ResultsAt the conclusion of the course, all students were able to successfully complete all of the multifaceted mental navigation exercises. Post-course survey data indicated that respondents perceived significant increases in their knowledge of cranial nerves; anterior, middle, and posterior skull base anatomy; anterior and posterior cranial circulation; and the ventricular system. Conclusion3D navigation-based fly-through instruction is a novel and effective technique for teaching complex anatomy and can provide learners with the foundational skills for developing and maintaining a 3D mental map of intracranial anatomy.

Human Brainstem and Cerebellum Atlas: Chemoarchitecture and Cytoarchitecture Paired to MRI.

Lesion localization is the basis for understanding neurologic disease, which is predicated on neuroanatomical knowledge carefully cataloged from histology and imaging atlases. However, it is often difficult to correlate clinical images of brainstem injury obtained by MRI scans with the details of human brainstem neuroanatomy represented in atlases, which are mostly based on cytoarchitecture using Nissl stain or a single histochemical stain, and usually do not include the cerebellum. Here, we report a high-resolution (200 μm) 7T MRI of a cadaveric male human brainstem and cerebellum paired with detailed, coregistered histology (at 2 μm single-cell resolution) of the immunohistochemically stained cholinergic, serotonergic, and catecholaminergic (dopaminergic, noradrenergic, and adrenergic) neurons, in relationship to each other and to the cerebellum. These immunohistochemical findings provide novel insights into the spatial relationships of brainstem cell types and nuclei, including subpopulations of melanin and TH+ neurons, and allows for more informed structural annotation of cell groups. Moreover, the coregistered MRI-paired histology helps validate imaging findings. This is useful for interpreting both scans and histology, and to understand the cell types affected by lesions. Our detailed chemoarchitecture and cytoarchitecture with corresponding high-resolution MRI builds on previous atlases of the human brainstem and cerebellum, and makes precise identification of brainstem and cerebellar cell groups involved in clinical lesions accessible for both laboratory scientists and clinicians alike.SIGNIFICANCE STATEMENT Clinicians and neuroscientists frequently use cross-sectional anatomy of the human brainstem from MRI scans for both clinical and laboratory investigations, but they must rely on brain atlases to neuroanatomical structures. Such atlases generally lack both detail of brainstem chemical cell types, and the cerebellum, which provides an important spatial reference. Our current atlas maps the distribution of key brainstem cell types (cholinergic, serotonergic, and catecholaminergic neurons) in relationship to each other and the cerebellum, and pairs this histology with 7T MR images from the identical brain. This atlas allows correlation of the chemoarchitecture with corresponding MRI, and makes the identification of cell groups that are often discussed, but rarely identifiable on MRI scan, accessible to clinicians and clinical researchers.

The influence of regions of interest on tractography virtual dissection protocols: general principles to learn and to follow.

Efficient communication across fields of research is challenging, especially when they are at opposite ends of the physical and digital spectrum. Neuroanatomy and neuroimaging may seem close to each other. When neuroimaging studies try to isolate structures of interest, according to a specific anatomical definition, a variety of challenges emerge. It is a non-trivial task to convert the neuroanatomical knowledge to instructions and rules to be executed in neuroimaging software. In the process called "virtual dissection" used to isolate coherent white matter structure in tractography, each white matter pathway has its own set of landmarks (regions of interest) used as inclusion and exclusion criteria. The ability to segment and study these pathways is critical for scientific progress, yet, variability may depend on region placement, and be influenced by the person positioning the region (i.e., a rater). When raters' variability is taken into account, the impact made by each region of interest becomes even more difficult to interpret. A delicate balance between anatomical validity, impact on the virtual dissection and raters' reproducibility emerge. In this work, we investigate this balance by leveraging manual delineation data of a group of raters from a previous study to quantify which set of landmarks and criteria contribute most to variability in virtual dissection. To supplement our analysis, the variability of each pathway with a region-by-region exploration was performed. We present a detailed exploration and description of each region, the causes of variability and its impacts. Finally, we provide a brief overview of the lessons learned from our previous virtual dissection projects and propose recommendations for future virtual dissection protocols as well as perspectives to reach better community agreement when it comes to anatomical definitions of white matter pathways.

The Development and Evaluation of Online Neuroanatomy Resources for OT Students

Of necessity for a practicing Occupational Therapist is the ability to demonstrate competent neuroanatomical knowledge through application into clinical practice. Yet, throughout the academic careers of Occupational Therapy (OT) students, neuroanatomy (NA) will consistently be perceived as one of the most difficult anatomical topics encountered. Rising in anatomical education is the use of computer assisted learning (CAL) due to its alignment with educational goals and student desires. This study aims to determine how neuroanatomy e‐modules (NEMs) can improve the perceptions and academic performance in NA of first year Master of Occupational Therapy (MScOT) students at Western University. In this descriptive study, 1st year MScOT students who studied NA without the use of NEMs (N = 61, nonNEM cohort) completed a Likert style survey examining perceptions of major NA topics. In addition, multiple choice exams (N = 109 questions) were analyzed to measure student performance on questions regarding NA topics, lower or higher order complexity, and clinical neurology. Four NEMs were then created and implemented into the next student cohort (N = 75, NEM cohort). Upon completion of the course, students were once again surveyed for perceived NA difficulty and final exam performance analyzed (N = 34). The overall self‐perceived NA knowledge of the students exposed NEMs were similar in comparison to non‐NEM cohort (p = .811), however, the cohort exposed to the NEMs demonstrated decreased perceived difficulty on all six NA topics surveyed, with a significant difference being found on cranial nerve difficulty (p = .007). Consistent with non‐NEM cohort, students in the NEM cohort still perceived the basal ganglia &amp; cerebellum, and spinal cord as the most difficult NA topics. When measuring academic performance, students in the NEM cohort demonstrated significant improvements in overall NA (p = .001), higher‐order NA (p = .001), and clinical neurology knowledge (p = .009), however no improvement in lower‐order NA knowledge was found (p =.122) Further, of the NA topics examined, students in the NEM cohort demonstrated significant improvement on cranial nerve‐based questions (p = .01) in comparison to the non‐NEM cohort. With the implementation of NEMs, the data from the present study demonstrates the efficacy of CAL emodules in improving NA performance and perceptions within OT curriculums. Of most significance is the improvement on higher order NA performance with the use of NEMs, as questions of this nature require greater critical thinking and application of knowledge, closely resembling what students will encounter in their clinical practice. Although further research on the interaction between performance and perceptions is still required, this study shows initial evidence of a relationship as students significantly improved their perceptions and performance, especially when it came to cranial nerve‐based questions. With the shift and modernization of educational standards, OT instructors should consider the implementation of CAL emodules into their curriculums as it can have significant benefits in the outcomes of OT students learning NA and their role in the treatment and rehabilitation of those with neurological conditions.