Abstract This chapter explores the integration of Problem-Based Learning (PBL), enhanced by Extended Reality (XR) technology, into undergraduate Human Anatomy and Physiology (A&P) courses. The study of A&P is foundational for health science programs, serving as a ‘gateway’ course for nearly half a million students annually in the US and Canada. Traditionally, A&P relies on didactic lectures and rote memorization, but the need for deeper clinical reasoning and applications that mirror professional practice necessitates pedagogical reform. PBL is well-suited to bridge the gap between structure and function by requiring students to solve complex, real-life patient dilemmas. Building on constructivist learning orientation, this chapter details the design and deployment of an innovative, online Unity3D application leveraging hardware like zSpace for 3D visualization of anatomical assets, including CT and MRI segmentations from willed body donor archives. The case studies focus on an XR-enhanced PBL model of an upper extremity trauma case that engages students in collaborative problem-solving, utilizing interactive H5P content and 3D model exploration. Evidence suggests that the XR activities significantly improve students’ confidence, ability to apply course content, and development of spatial reasoning, offering a promising and effective instructional supplement to traditional A&P teaching.

Sex estimation is a core component of the biological profile, and the skull has long been regarded as a primary skeletal element for this purpose. However, morphological studies focusing on the skull base remain limited. This study aimed to derive discriminant functions using skull base measurements for sex estimation in modern Korean skeletal samples. Three-dimensional models of the skull base were generated from CT images of 198 decedents (103 males, 95 females), and 31 measurements were subjected to statistical analysis. Descriptive statistics revealed significant sexual dimorphism across all variables, with males exhibiting greater mean values than females in every measurement (p < 0.05). Discriminant function equations were subsequently derived to facilitate sex classification. Univariate analyses yielded accuracies ranging from 61.6% to 83.8%, while a stepwise method incorporating five variables distributed across the overall skull base structure achieved a relatively high accuracy of 86.4%. To reflect forensic situations involving fragmentary remains, side-specific stepwise equations were developed; the right-side model achieved 83.3% accuracy, and the left-side model 78.8%. These findings support the utility of skull base measurements for sex estimation in a modern Korean population and highlight their applicability in forensic anthropology.

This prospective repeated-measures quasi-experimental educational study, conducted across two consecutive first-year medical school cohorts, aimed to develop and implement case-based learning (CBL) modules using three-dimensional (3D) models and magnetic resonance imaging (MRI) within an extended reality (XR) environment. The intervention integrated anatomical variations and anomalies to enhance immediate learning and long-term knowledge retention. MRI data from selected donors at the John A. Burns School of Medicine (JABSOM) were used to create XR-CBL modules. First-year medical students from the classes of 2024 (Cohort 2021) (n = 61) and 2025 (Cohort 2022) (n = 67) participated. Before the session, students received an email detailing the activity. During the gross anatomy laboratory, they accessed a website to explore cases featuring learning objectives, clinical and radiological data, 3D models, and MRIs. The XR experience utilized desktop-based XR technology. An assessment was administered before, immediately after, and eight weeks post-intervention. Students also completed a mixed-format feedback survey. A repeated-measures ANOVA revealed a significant effect of the intervention on student performance across both cohorts. For Cohort 2021, Wilks’ Lambda = 0.384, F (2, 59) = 47.27, p < 0.001, partial η² = 0.616. For Cohort 2022, Wilks’ Lambda = 0.30, F (2, 65) = 72.72, p < 0.001, partial η² = 0.691. Follow-up pairwise comparisons with Bonferroni adjustments indicated significant improvements from pre-test to post-test and from pre-test to post-post-test for both cohorts (p < 0.01). There was no significant difference between the post-test and post-post-test scores (p = 1.00). In Cohort 2021, mean scores significantly increased from pre-test (3.9 ± 1.9) to post-test (6.2 ± 2.6) and were maintained at post-post-test (6.3 ± 1.7). Similarly, Cohort 2022 demonstrated significant gains from pre-test (4.3 ± 1.6) to post-test (7.6 ± 2.2), with high retention at post-post-test (6.3 ± 2.4). Pairwise comparisons confirmed that improvements from baseline were significant (p < 0.01), while no significant decay occurred between post- and post-post-assessments (p = 1.00). Incorporating multimodal resources, including anatomical variations and anomalies through CBL, into the gross anatomy laboratory was associated with significant score improvements and positive student perceptions. Learners reported that the interactive, imaging-based tools helped them better understand complex anatomical relationships, particularly when anatomical variability was highlighted.

Facial reconstruction in forensic anthropology is a technique to identify individuals from skeletal remains. This process is heavily reliant on accurately estimating facial features, particularly the eyes, which are the most distinctive features for facial recognition. This study aimed to analyze the anatomical relationship between the palpebral fissure and the orbit in Koreans to enhance the accuracy of facial reconstruction in 105 participants (55 males, 50 females) with a mean age of 26.0 years for males and 26.5 years for females. Measurements were obtained by superimposing 2D photographs obtained using a Head Posture Aligner with 3D skull models scanned via Cone Beam Computed Tomography. The study analyzed various anatomical landmarks on the eyelids, pupils, irises, and orbits for sex-based differences and left-right asymmetry. Results indicated more significant structural variability in the horizontal plane than in the vertical, with males exhibiting larger differences than females. Notable left-right asymmetry was observed across all horizontal variables. High regression coefficients were noted for both sexes along the reference line through the supraorbitale, whereas landmarks along the medial orbit showed lower regression coefficients. This study underscores the importance of precise landmark identification and measurement in facial reconstructions, where superimposition is crucial for estimating soft tissue placement over skeletal frameworks. The insights gained from the measurements of the palpebral fissure contribute valuable information to improving the accuracy and applicability of facial reconstruction in forensic anthropology.

Accurate sex estimation is crucial for comprehensive analysis of the biological profiles of unidentified human skeletal remains. However, there is a notable lack of research specifically addressing the morphometrics of the hard palate. Therefore, this study aimed to derive discriminant equations using the hard palate and assess their applicability for sexing partial skeletal remains in a contemporary Korean population. Statistical analyses were performed for 24 measurements derived from three-dimensional models of the hard palate, generated using computed tomography scans of 301 individuals (156 males, 145 females). Descriptive statistics revealed significant sexual dimorphism in the mean comparison of hard palate sizes between Korean males and females, with males exhibiting larger palates across all measurements (p < 0.05). Discriminant function score equations were generated to aid in sex determination. Univariate analysis yielded an accuracy range of 57.8-75.1%, whereas the stepwise method achieved an accuracy of 80.7% with five selected variables: IF-PNS, GFL-GFR, IF-GFR, Pr-EcL, and Pr-EnR. The results of this metric analysis demonstrate the usefulness of the hard palate for sex estimation in the contemporary Korean population. These findings have potential implications for forensic investigations, archeological studies, and population-specific anatomical research.

The nose is a prominent feature for facial recognition and reconstruction. To investigate the relationship of the nasal shape with the piriform aperture in Korean adults and juveniles, we performed regression analysis. By regression analysis, prediction equations for nasal shape were obtained in relation to the shape of the piriform aperture considering sex and age groups.Three-dimensional skull and face models, rendered from computed tomography images, were assessed (331 males and 334 females). Juveniles (<20 years) were divided into three age groups according to the development of the dentition. Adults were divided into three age groups of two decades each, according to their age. To measure the nasal area, nine landmarks and nine measurements were chosen, while seven landmarks and five measurements were selected to measure the piriform aperture area. Four measurements were defined to explain the direct relationship between the nasal aperture and nasal shape.First, descriptive statistical analyses were performed according to sex and age groups. Subsequently, the correlation of nasal soft tissue measurements with piriform measurements was analyzed. Last, we performed a linear regression analysis of the measurements with higher correlations, considering sex and age groups as variables. Prediction equations were used to estimate the nasal bridge length, height, protrusion, and width. Equations considering sex and age groups showed better explanation ability. Measurements related to the height of the nasal bridge presented improvement. This study may assist in the more accurate approximation of nasal shape in facial reconstruction.

The auricular cartilage, which is typically soft and flexible, can calcify or ossify because of diseases such as diabetes mellitus, trauma, radiation therapy for cancer, and more commonly from frostbite. Calcified, ossified, or hardened auricular cartilage is a rare finding in the clinical literature and appears to be absent in the physical and forensic anthropological literature. This study examines the ossified auricular cartilage and tests whether the hypothesis can be identified in postmortem skeletonized tissue and be part of the external auditory meatus. A total of 290 crania were examined for accessory ossicles. A descriptive and interpretative analysis was performed grossly, histologically, and morphometrically to document the morphology and location of the ossicles, investigate their structure, and perform hypothesis testing. Results revealed that seven females and one male crania from a total of 290 crania (2.76%) exhibit semi-ossified auricular cartilage attached to the tympanic plate of the temporal bone. The morphology and location of the ossicles at the junction of the auricle and external auditory meatus indicate they are hardened auricular cartilage that was verified with histological observations. Regression analysis indicates that addition of the ossicle to the depth of the auditory tube significantly changes coefficient of determination (R2) with respect to cranial breadth. In conclusion, results indicate that small cartilaginous structures of the external ear may ossify forming accessory tympanic plate ossicles that potentially could be identified in skeletal remains as a new osteological entity. This report highlights the types of information that can be gained using an approach that integrates forensic anthropology, gross anatomy, and histology.

Background: Down syndrome (DS) is a genetic condition characterized by an extra copy of chromosome 21, resulting in various physical and cognitive features. This study aimed to comprehensively analyze the dental and craniofacial morphology of individuals with DS using Cone Beam Computed Tomography (CBCT). Methods: Six individuals with DS, comprising five males and one female aged 17 to 35 years, underwent CBCT scanning. Radiographic assessments included dentition, occlusion, paranasal sinuses, airway, skull bones, and suture calcification. Linear and angular cephalometric measurements were performed, and airway analysis was conducted using Dolphin 3D imaging software v.11. Results: The study revealed prognathic maxilla in five patients, prognathic mandible in four, and bimaxillary protrusion in two. Dental findings included microdontia, enamel hypoplasia, and congenitally missing teeth, with maxillary and mandibular third molars most commonly absent. Sinus abnormalities, delayed suture closure, and cervical spine anomalies were also observed. Conclusion: These findings contribute to a deeper understanding of DS-related craniofacial characteristics and emphasize the importance of considering these morphometric features in clinical management strategies for individuals with DS. This study’s limited sample size underscores the significance of radiographic assessment in planning interventions such as cosmetic reconstructions, prosthetic rehabilitation, or orthodontic treatment for individuals with DS.

Anatomy instructional methods varied widely during the COVID-19 pandemic and programs are assessing innovations for retention. Learning preferences were assessed among medical students dichotomized as elective dissectors (ED) or non-dissectors (ND) during the COVID-19 partial re-opening in 2020 (preclinical) and again in 2022 after clinical exposure (post-clinical) to assess the viability of elective dissection post-pandemic. A mixed-method approach was used for the assessment of test scores, learning preference surveys, learning activities rankings, and thematic analyses. No significant differences occurred in anatomy examination scores. Dissection was considered useful by both preclinical groups but significantly more so by ED, while the presence of an instructor was significantly preferred by ED although a majority of ND agreed. Elective dissection was significantly preferred by ND but also by a large minority of ED students. Pre- and post-clinical ND believed that elective dissection offered more academic flexibility, did not hinder clinical learning, and did not negatively impact medical education. The corresponding ED stated that confidence improved, clinical experiences were enhanced, and dissection was irreplaceable. Preclinical ND preferred self-learning, while ED students preferred online learning, but these differences largely disappeared post-clinically. Learning activity rankings were not significantly different among all groups (ND, ED, preclinical, and post-clinical). A hybrid laboratory with a virtual learning environment ranked highest across groups and preferences increased over time suggesting that students benefited from this instructional method during clinical exposure. The absence of laboratory experience ranked lowest, and preference decreased over time suggesting that anatomy dissection is valued.

Cholesterol granuloma is a histopathological finding characterized by a mass of connective tissue and granulation tissue. It is primarily observed in the middle ear, mastoid process, or paranasal sinuses, with rare occurrences in the dental odontogenic region. A dentigerous cyst encloses the crown of an unerupted tooth by expanding its follicle and attaches to the neck of the tooth. Here, we report a 63-year-old female who presented to the dental clinic complaining of an ill-fitted denture. A panoramic radiograph showed a well-defined radiolucent lesion in the upper left maxillary sinus with an impacted third molar. Computed tomography revealed loss of the anterior and lateral sinus walls. The cyst was enucleated surgically. The final diagnosis was confirmed by histopathological examination, which revealed focal areas of cholesterol clefts in the cystic wall of the dentigerous cyst.

Objective: To understand trends in neuronavigation we employed machine learning methods to perform a broad literature review which would be impractical by manual inspection. Methods: PubMed was queried for articles with "Neuronavigation" in any field from inception-2020. Articles were designated neuronavigation-focused (NF) if "Neuronavigation" was a major MeSH. The latent dirichlet allocation topic modeling technique was used to identify themes of NF research. Results: There were 3896 articles of which 1727 (44%) were designated as NF. Between 1999-2009 and 2010-2020, the number of NF publications experienced 80% growth. Between 2009-2014 and 2015-2020, there was a 0.3% decline. Eleven themes covered 1367 (86%) NF articles. "Resection of Eloquent Lesions" comprised the highest number of articles (243), followed by "Accuracy and Registration" (242), "Patient Outcomes" (156), "Stimulation and Mapping" (126), "Planning and Visualization" (123), "Intraoperative Tools" (104), "Placement of Ventricular Catheters" (86), "Spine Surgery" (85), "New Systems" (80), "Guided Biopsies" (61), and "Surgical Approach" (61). All topics except for "Planning and Visualization", "Intraoperative Tools", and "New Systems" exhibited a monotonic positive trend. When analyzing subcategories, there were a greater number of clinical assessments or usage of existing neuronavigation systems (77%) rather than modification or development of new apparatuses (18%). Conclusion: NF research appears to focus on the clinical assessment of neuronavigation and to a lesser extent on the development of new systems. Although neuronavigation has made significant strides, NF research output appears to have plateaued in the last decade.

Eyebrows are the most important facial feature in facial recognition with its shape rated to be more helpful than color or density for facial reconstruction or approximation. However, little extant research has estimated the position and morphological territory of the eyebrow from the orbit. Three-dimensional craniofacial models, produced from CT scans of 180 Koreans autopsied at the National Forensic Service Seoul Institute, were used to conduct metric analyses of subjects (125 males and 55 females) between 19 and 49 (mean 35.1) years. We employed 18 craniofacial landmarks to examine the morphometry of the eyebrow and orbit with 35 pairs of distances per subject measured between landmark and reference planes. Additionally, we used linear regression analyses to predict eyebrow shape from the orbit for every possible combination of variables. The morphology of the orbit has more influence on the position of the superior margin of the eyebrow. In addition, the middle part of the eyebrow was more predictable. The highest point of the eyebrow in female was located more medially than the male. Based on our findings, the equations for estimating the position of the eyebrow from the shape of the orbit is useful information for face reconstruction or approximation.

Background: The purpose of this study is to characterize a full-term conjoined twins’ cadaver curated by Dr. Jacob Henle sometime between 1844 and 1852 and demonstrate digital distribution of an old and rare medical museum specimen using an extended reality (XR) model workflow. Methods: The cadaver (Preparation 296) is in the Department of Anatomy and Cell Biology at the University of Heidelberg. An XR display workflow comprises image capture, segmentation, and visualization using CT/MR scans derived from the cadaver. Online radiology presentation to medical students focuses on diagnostic characteristics of anatomical systems depicted with XR models. Results: Developmental defects in Preparation 296 include duplicated supradiaphragmatic structures and abnormal osteological features. Subdiaphragmatically, the gut is continuous on the right, but terminates at the distal esophagus on the left. One large liver occupies the abdomen with one spleen located on the left side. Observations suggest duplication of the primitive streak and separate notochords rostrally. Duplication occurs near the yolk sac and involves midgut formation while secondary midline fusion of the upper extremities and ribs likely results from the proximity of the embryos during development. Medical students access the model with device agnostic software during the curricular topic “Human Body Plan” that includes embryology concepts covering mechanisms of twinning. Conclusions: The workflow enables ease-of-access XR visualizations of an old and rare museum specimen. This study also demonstrates digital distribution and utilization of XR models applicable to embryology education.

The initial interaction between medical students and their "Silent Teacher" in the dissection lab is an important experience in the process of establishing a professional ethos. However, COVID19 complicated this process and the optimal approach to achieve this introduction remains unclear. The purpose of this study was to develop an online case-based approach as the basis for donor introduction to medical students based on Magnetic resonance imaging (MRI) reports. MRI scans of 16 body donors were assessed by a radiologist and observations were uploaded to a web-based DICOM viewer (www.rad3d.com). A list of learning objectives were generated for each donor and radiology reports were constructed based on: chief complaints, medical history, radiology and pathology that were reviewed prior to the class. Within the lab and following COVID19 restriction policy, students read through the radiology reports and viewed the augmented reality (AR) visualizations of the MRI scans using z-space computers providing additional dissection team interactions. Finally, surface anatomy exercises were undertaken that corresponded to the primary pathology providing a direct interaction with the donor. This process included Sketchfab and other links to underscore anatomical correlations (Figure 1). A survey was conducted to assess student perceptions of the experience. The study design comprised a voluntary survey tool to assess student level of anxiety and whether the online approach was effective. Response scales were either bimodal or Likert-base (5 scale) and analyzed with Fisher's exact test. Follow up open ended questions were also presented to the students. The response rate was 33/80 (41.25%). Most students (82.7%) felt anxious first, but the anxiety decreased in time (60.7%). They mostly accomplished the tasks (surface exercises 97%; reviewing MRIs 87.9%) and found surface exercises useful in terms of reducing anxiety (90.6%), and initiating team work (100%). A total of 79.3% of the students found MR useful for learning radiology (Table 1). More than half of the students (55.6%) indicated that the first encounter was not as they expected and stated that they thought it would be more intimidating. Several emotions were indicated such as: confused, uncomfortable, somber, excited, grateful, thankful, professional. They all agreed that using a case based approach as an introductory laboratory prior to first dissection is useful. There was one prominent suggestion almost all students stated: video resources prior to the lab. Results suggest that humanizing the donor, implementing clinical reasoning, and initiating teamwork provided a positive first lab experience using online resources. Future work will be aimed at further development of online resources organized around clinical presentation using MR scans.

Purpose: Extended reality (XR) technology enhances learning in medical education. The purpose of this study was to develop and apply a case-based approach for teaching radiological anatomy utilizing XR technology for improved student exploration and engagement. Methods: The workflow consisted of MRI scanning cadavers followed by radiological, pathological, and anatomical assessment, and finally case presentation based on XR visualizations and student interaction. Case information (Subject, History, and Physical Exam) was presented to student groups who generated and recorded hypotheses using Google Forms. Results: Use of all components of the system was voluntary and a total of 74 students responded to the survey request (response rate = 95%). Assessment of the experience was conducted through a qualitative survey comprising four Likert scale questions (1-5, 1 lowest), three binary questions, and open-ended comments. Mean, standard deviation, and overall agreement (mean +/- SD, OA) showed that students found MRI scans of cadavers to be helpful for dissections (4.14 +/- 1.1, 74.3%) and provided an understanding of relevant anatomy (4.32 +/- 0.9, 79.7%), while 78.4% of students used the DICOM viewer to visualize scans of cadavers. The difficulty of use was found to be average (2.90 +/- 1.0, 23%). zSpace visualizations were used by 40.5% of students, generally agreeing that an understanding of spatial relationships improved as a result (3.60 +/- 1.0, 43.2%). More case-based sessions were favored by 97.3% of students. Conclusions: Results suggest that cadaveric MRI radiological visualization and XR technology enhance understanding of case-based anatomical dissections and encourage student exploration and engagement.

Educational technologies in veterinary medicine aim to train veterinarians faster and improve clinical outcomes. COVID-19 pandemic, shifted face-to-face teaching to online, thus, the need to provide effective education remotely was exacerbated. Among recent technology advances for veterinary medical education, extended reality (XR) is a promising teaching tool. This study aimed to develop a case resolution approach for radiographic anatomy studies using XR technology and assess students' achievement of differential diagnostic skills. Learning objectives based on Bloom's taxonomy keywords were used to develop four clinical cases (3 dogs/1 cat) of spinal injuries utilizing CT scans and XR models and presented to 22 third-year veterinary medicine students. Quantitative assessment (ASMT) of 7 questions probing 'memorization', 'understanding and application', 'analysis' and 'evaluation' was given before and after contact with XR technology as well as qualitative feedback via a survey. Mean ASMT scores increased during case resolution (pre 51.6% (±37%)/post 60.1% (± 34%); p < 0.01), but without significant difference between cases (Kruskal-Wallis H = 2.18, NS). Learning objectives were examined for six questions (Q1-Q6) across cases (C1-4): Memorization improved sequentially (Q1, 2 8/8), while Understanding and Application (Q3,4) showed the greatest improvement (26.7%-76.9%). Evaluation and Analysis (Q5,6) was somewhat mixed, improving (5/8), no change (3/8) and declining (1/8).Positive student perceptions suggest that case studies' online delivery was well received stimulating learning in diagnostic imaging and anatomy while developing visual-spatial skills that aid understanding cross-sectional images. Therefore, XR technology could be a useful approach to complement radiological instruction in veterinary medicine.

Due to the COVID‐19 pandemic, there is increased interest to effectively deliver educational curricula remotely to diverse student populations. Case‐based cadaveric MRI visualization and extended reality (XR) technology enhances learning experiences in medicine. The purpose of this study was to demonstrate that a virtual, multi‐departmental workflow utilizing MRI, XR technology, and a “patient” group, represented by the John A. Burns School of Medicine (JABSOM) Willed Body Program, supplements case‐based learning and promotes student exploration and engagement equally in cross‐cultural cohorts represented by American and Turkish medical students.