The development of a virtual 3D model of the renal corpuscle from serial histological sections for E-learning environments

Ultrastructural analysis of whole glomeruli using array tomography

The renal glomerulus produces primary urine from blood plasma by ultrafiltration. The ultrastructure of the glomerulus is closely related to filtration function and disease development. The ultrastructure of glomeruli has mainly been evaluated using transmission electron microscopy; however, the volume that can be observed using transmission electron microscopy is extremely limited relative to the total volume of the glomerulus. Consequently, observing structures that exist in only one location in each glomerulus, such as the vascular pole, and evaluating low-density or localized lesions are challenging tasks. Array tomography (AT) is a technique used to analyze the ultrastructure of tissues and cells via scanning electron microscopy of serial sections. In this study, we present an AT workflow that is optimized for observing complete serial sections of the whole glomerulus, and we share several analytical examples that use the optimized AT workflow, demonstrating the usefulness of this approach. Overall, this AT workflow can be a powerful tool for structural and pathological evaluation of the glomerulus. This workflow is also expected to provide new insights into the ultrastructure of the glomerulus and its constituent cells.

Histology as a paradigm for a science-based learning experience: Visits by histology education spirits of past, present, and future

The term "histology" was coined a little over 200 years ago and the subject has always relied on microscopy as its defining technology. Microscopy was and still is an essential approach for the description of cellular components and their arrangements in living organisms. For more than a century and a half, histology or microanatomy has also been part of the basic science education for biomedical students. Traditionally, it has been taught in two major components, a didactic transfer of information, either in a lecture or self-learning format, and in active-learning laboratory sessions. These two modes of histology instruction conform with the dual-processing theory of learning, one being more automatic and depending mainly on rote memorization, whereas the other is analytical, requiring more advanced reasoning skills. However, these two components of histology education are not separate and independent, but rather complementary and part of a multi-step learning process that encourages a scientific analysis of visual information and involves higher-level learning skills. Conventional, as well as modern electronic instruction methods (e-learning) have been used in complementary ways to support the integrated succession of individual learning steps as outlined in this manuscript. However, as recent curricular reforms have curtailed instructional time, this traditional format of teaching histology is no longer sustainable and a reflective reassessment of the role of histology in modern biomedical education is a timely necessity.

Virtual Microscopy Goes Global: The Images Are Virtual and the Problems Are Real

For the last two centuries, the scholarly education of histology and pathology has been based on technology, initially on the availability of low-cost, high-quality light microscopes, and more recently on the introduction of computers and e-learning approaches to biomedical education. Consequently, virtual microscopy (VM) is replacing glass slides and the traditional light microscope as the main instruments of instruction in histology and pathology laboratories. However, as with most educational changes, there are advantages and disadvantages associated with a new technology. The use of VM for the teaching of histology and pathology requires an extensive infrastructure and the availability of computing devices to all learners, both posing a considerable financial strain on schools and students. Furthermore, there may be valid reasons for practicing healthcare professionals to maintain competency in using light microscopes. In addition, some educators may be reluctant to embrace new technologies. These are some of the reasons why the introduction of VM as an integral part of histology and pathology instruction has been globally uneven. This paper compares the teaching of histology and pathology using traditional or VM in five different countries and their adjacent regions, representing developed, as well as developing areas of the globe. We identify general and local roadblocks to the introduction of this still-emerging didactic technology and outline solutions for overcoming these barriers.

Are stereotypes in decline? The portrayal of female anatomy in e-learning

Sex and gender bias in anatomy learning materials are considered a "hidden obstacle" to gender equity in medical curricula. The purpose of this study was to investigate whether quantitative sex and gender biases do exist in popular anatomy e-learning platforms and compare the results with those found in contemporary textbooks and atlases. A systematic content-analysis was performed on N = 3767 images published from 2008 to 2021 in which sex/gender could be identified by considering technical aspects of illustration and various intersectional categories. E-learning platforms took into account an appropriate representation of the female body and presented even more females (n = 932/1412; 66%), more frequently from a ventral/anterior (χ²  = 26, P < 0.001) and whole-body perspective (χ²  = 27, P < 0.001). This was in contrast to German anatomy books, where the results pointed to a significant sex and gender bias. For example, all books assessed underrepresented females (n = 707/2355; 30%) and placed them in stereotypical sex-specific context (χ²  = 348, P < 0.001), showing them more often from a caudal/inferior (χ²  = 99, P < 0.001) and internal (χ²  = 132, P < 0.001) perspective. Altogether, the visual representation of sex and gender in anatomical curricula is still biased and the stereotypical perceptions of human anatomy seem to be a global issue. However, the increasing use of electronic learning platforms, which gradually replace traditional books is changing the way the male and female body is depicted, which might offer new opportunities for reducing stereotypes in anatomy education.

E-Learning Three-Dimensional Anatomy of the Brainstem: Impact of Different Microscopy Techniques and Spatial Ability

Polarized light imaging (PLI) is a new method which quantifies and visualizes nerve fiber direction. In this study, the educational value of PLI sections of the human brainstem were compared to histological sections stained with Luxol fast blue (LFB) using e-learning modules. Mental Rotations Test (MRT) was used to assess the spatial ability. Pre-intervention, post-intervention, and long-term (1 week) anatomical tests were provided to assess the baseline knowledge and retention. One-on-one electronic interviews after the last test were carried out to understand the students' perceptions of the intervention. Thirty-eight medical students, (19 female and 19 males, mean age 21.5 ± SD 2.4; median age: 21.0 years) participated with a mean MRT score of 13.2 ± 5.2 points and a mean pre-intervention knowledge test score of 49.9 ± 11.8%. A significant improvement in both, post-intervention and long-term test scores occurred after learning with either PLI or LFB e-learning module on brainstem anatomy (both P < 0.001). No difference was observed between groups in post-intervention test scores and long-term test scores (P = 0.913 and P = 0.403, respectively). A higher MRT-score was significantly correlated with a higher post-intervention test score (rk  = 0.321; P < 0.05, respectively), but there was not a significant association between the MRT- and the long-term scores (rk = -0.078; P = 0.509). Interviews (n = 10) revealed three major topics: Learning (brainstem) anatomy by use of e-learning modules; The "need" of technological background information when studying brainstem sections; and Mnemonics when studying brainstem anatomy. Future studies should assess the cognitive burden of cross-sectional learning methods with PLI and/or LFB sections and their effects on knowledge retention.

Low-flow intussusception and metastable VEGFR2 signaling launch angiogenesis in ischemic muscle

Efforts to promote sprouting angiogenesis in skeletal muscles of individuals with peripheral artery disease have not been clinically successful. We discovered that, contrary to the prevailing view, angiogenesis following ischemic muscle injury in mice was not driven by endothelial sprouting. Instead, real-time imaging revealed the emergence of wide-caliber, primordial conduits with ultralow flow that rapidly transformed into a hierarchical neocirculation by transluminal bridging and intussusception. This process was accelerated by inhibiting vascular endothelial growth factor receptor-2 (VEGFR2). We probed this response by developing the first live-cell model of transluminal endothelial bridging using microfluidics. Endothelial cells subjected to ultralow shear stress could reposition inside the flowing lumen as pillars. Moreover, the low-flow lumen proved to be a privileged location for endothelial cells with reduced VEGFR2 signaling capacity, as VEGFR2 mechanosignals were boosted. These findings redefine regenerative angiogenesis in muscle as an intussusceptive process and uncover a basis for its launch.

Julich-Brain: A 3D probabilistic atlas of the human brain’s cytoarchitecture

Cytoarchitecture is a basic principle of microstructural brain parcellation. We introduce Julich-Brain, a three-dimensional atlas containing cytoarchitectonic maps of cortical areas and subcortical nuclei. The atlas is probabilistic, which enables it to account for variations between individual brains. Building such an atlas was highly data- and labor-intensive and required the development of nested, interdependent workflows for detecting borders between brain areas, data processing, provenance tracking, and flexible execution of processing chains to handle large amounts of data at different spatial scales. Full cortical coverage was achieved by the inclusion of gap maps to complement cortical maps. The atlas is dynamic and will be adapted as mapping progresses; it is openly available to support neuroimaging studies as well as modeling and simulation; and it is interoperable, enabling connection to other atlases and resources.

A Virtual 3D Dynamic Model of Caries Lesion Progression as a Learning Object for Caries Detection Training and Teaching: Video Development Study

BACKGROUND

In the last decade, 3D virtual models have been used for educational purposes in the health sciences, specifically for teaching human anatomy and pathology. These models provide an opportunity to didactically visualize key spatial relations that can be poorly understood when taught by traditional educational approaches. Caries lesion detection is a crucial process in dentistry that has been reported to be difficult to learn. One especially difficult aspect is linking clinical characteristics of the different severity stages with their histological features, which is fundamental for treatment decision-making.

OBJECTIVE

This project was designed to develop a virtual 3D digital model of caries lesion formation and progression to aid the detection of lesions at different severity stages as a potential complement to traditional lectures.

METHODS

Pedagogical planning, including identification of objectives, exploration of the degree of difficulty of caries diagnosis-associated topics perceived by dental students and lecturers, review of the literature regarding key concepts, and consultation of experts, was performed prior to constructing the model. An educational script strategy was created based on the topics to be addressed (dental tissues, biofilm stagnation areas, the demineralization process, caries lesion progression on occlusal surfaces, clinical characteristics related to different stages of caries progression, and histological correlations). Virtual 3D models were developed using the Virtual Man Project and refined using multiple 3D software applications. In the next phase, computer graphic modelling and previsualization were executed. After that, the video was revised and edited based on suggestions. Finally, explanatory subtitles were generated, the models were textured and rendered, and voiceovers in 3 languages were implemented.

RESULTS

We developed a 6-minute virtual 3D dynamic video in 3 languages (English, Spanish, and Brazilian Portuguese) intended for dentists and dental students to support teaching and learning of caries lesion detection. The videos were made available on YouTube; to date, they have received more than 100,000 views.

CONCLUSIONS

Complementary pedagogical tools are valuable to support cariology education. This tool will be further tested in terms of utility and usability as well as user satisfaction in achieving the proposed objectives in specific contexts.

Comparison of Magnetic Resonance Angiography and Computed Tomography Angiography Stereoscopic Cerebral Vascular Models

In this paper, we will discuss and compare the stereoscopic models developed from two types of radiographic data, Magnetic Resonance Angiography (MRA) images and Computed Tomography Angiography (CTA) images. Stereoscopic models were created using surface or volume segmentation and semi-auto combined segmentation techniques. Although, the CTA data were found to improve the speed and quality of constructing virtual vascular models compared to conventional CT data, small blood vessels were difficult to capture during the imaging and reconstruction process thereby limiting the fidelity of the stereoscopic models. Thus, high contrast Magnetic Resonance Angiography (MRA) images offer better resolution to visualize and capture the smaller branches of the cerebral vasculature than CTA images.

Anatomy Visualizations Using Stereopsis: Current Methodologies in Developing Stereoscopic Virtual Models in Anatomical Education

Technology for developing three-dimensional (3D) virtual models in anatomical sciences education has seen a great improvement in recent years. Various data used for creating stereoscopic virtual models have also been constantly improving. This paper focuses specifically on the methodologies of creating stereoscopic virtual models and the techniques and materials used in developing stereoscopic virtual models from both our previous studies and other published literature. The presentation and visualization of stereoscopic models are highlighted, and the benefits and limitations of stereoscopic models are discussed. The practice of making 3D measurements on the lengths, angles, and volumes of models can potentially be used to help predict typical measurement parameters of anatomical structures and for the placement of surgical instruments. Once stereoscopic virtual models have been constructed, their visualization and presentation can be implemented in anatomy education and clinical surgical trainings.

Histology in 3D: development of an online interactive student resource on epithelium

Epithelium is an important and highly specialised tissue type that makes up the lining of inner and outer surfaces of the human body. It is proposed that a self-study tool adds to efficient learning and lecturing on this complicated topic in medical curricula. This paper describes the development and evaluation of an online interactive 3D resource on epithelium for undergraduate medical students. A first evaluation was carried out by means of an online survey (n = 37). The resource was evaluated positively on the website in general, its visual contents and its value and potential for the medical curriculum.

From chalkboard, slides, and paper to e-learning: How computing technologies have transformed anatomical sciences education

Until the late-twentieth century, primary anatomical sciences education was relatively unenhanced by advanced technology and dependent on the mainstays of printed textbooks, chalkboard- and photographic projection-based classroom lectures, and cadaver dissection laboratories. But over the past three decades, diffusion of innovations in computer technology transformed the practices of anatomical education and research, along with other aspects of work and daily life. Increasing adoption of first-generation personal computers (PCs) in the 1980s paved the way for the first practical educational applications, and visionary anatomists foresaw the usefulness of computers for teaching. While early computers lacked high-resolution graphics capabilities and interactive user interfaces, applications with video discs demonstrated the practicality of programming digital multimedia linking descriptive text with anatomical imaging. Desktop publishing established that computers could be used for producing enhanced lecture notes, and commercial presentation software made it possible to give lectures using anatomical and medical imaging, as well as animations. Concurrently, computer processing supported the deployment of medical imaging modalities, including computed tomography, magnetic resonance imaging, and ultrasound, that were subsequently integrated into anatomy instruction. Following its public birth in the mid-1990s, the World Wide Web became the ubiquitous multimedia networking technology underlying the conduct of contemporary education and research. Digital video, structural simulations, and mobile devices have been more recently applied to education. Progressive implementation of computer-based learning methods interacted with waves of ongoing curricular change, and such technologies have been deemed crucial for continuing medical education reforms, providing new challenges and opportunities for anatomical sciences educators. Anat Sci Educ 9: 583-602. © 2016 American Association of Anatomists.