Anatomy of the Buccal Space: Surgical and Radiological Perspectives.

Among the anatomical spaces in the head and neck area, the buccal space has often been studied in dental/oral surgery and cosmetic surgery because it contains the facial vessels, mandibular and facial nerves, and adipose tissue called the buccal fat pad. In addition, as the space can communicate with other spaces, it can be significant in infections. Although the anatomy of the buccal space has been reported in several studies, there have been discrepancies concerning its boundaries, and its communications have often been overlooked. The aim of this review is to examine the anatomy of buccal space including its boundaries, contents, continuity with adjacent spaces, and clinical significance. A literature review was performed on Google Scholar and PubMed. The literature has depicted the anterior, medial, and lateral boundaries more or less consistently, but descriptions of the posterior, superior, and inferior borders are controversial. The buccal space includes the facial arteries, veins, facial nerves, parotid duct, and lymph nodes, which can be described differently depending on definitions and the extent of the space. As it communicates with other anatomical spaces including the masticatory space, it can be a reservoir and a channel for infections and tumors. Buccal fat pads have various clinical applications, from a candidate for flap reconstruction to a target for removal for cosmetic purposes. This review will help understand the anatomy of the buccal space including its boundaries, residing structures, and communication with other spaces from surgical and radiological perspectives.

Evolution of the term "epicondyle of the femur": Revisiting the anatomical and surgical literature.

The femoral epicondyle is an anatomical bony landmark essential for surgeons and anatomists, but there are discrepancies between the two fields when using this term. In current orthopedic surgery, it commonly denotes the small bony prominence of the femoral condyle. Given the derivation, "epicondyle" should be a region projecting laterally from the articular surface rather than a point. These discrepancies in usage are found not only between the fields but also in the literature. This article reviews the narrative definition of "epicondyle of the femur" in surgery and the evolution of the term in anatomy. The outcomes of the review suggest a relationship between the differing perceptions of the epicondyle and the evolution of the term. In reports of studies related to the epicondyle, it is strongly recommended that the definition of the word is clearly stated, with an understanding of its evolution.

Visible Korean based on true color sectioned images for making realistic digital human, twenty years' record: a review.

PURPOSE: Visible Korean (VK) consists of two-dimensional (2D) images and three-dimensional (3D) models. The VK is used in various educational tools and research sources for anatomy. In this paper, we report on the records of the VK over 20 years. METHODS: Research papers related to Visible Korean were reviewed. RESULTS: Through this report of VK records, we highlighted the essential points for making true color and ultra-high-resolution sectioned images of human and animal bodies, for making various 2D and 3D applications from the sectioned images, and for good use of the sectioned images and their applications. CONCLUSION: In this metaverse age that various virtual environments are required in medical education and research, the VK dataset meets the reality of virtual human models as fundamental data owing to the actual color and high resolution of the VK dataset.

Lymph Node Stations of Pancreas Which Are Identified in Real Color Sectioned Images of a Cadaver With Pancreatic Cancer.

BACKGROUND: In pancreatic cancer surgery, anatomical understanding of lymph node metastases is required. Distinguishing lymph nodes in computed tomography or magnetic resonance imaging is challenging for novice doctors and medical students because of their small size and similar color to surrounding tissues. This study aimed to enhance our understanding of the clinical anatomy of lymph node stations relevant to pancreatic cancer using newly sectioned images of a cadaver with true color and high resolution and their three-dimensional (3D) models. METHODS: An 88-year-old female cadaver who died of pancreatic cancer was serially sectioned. Among the sectioned images of the whole body (0.05 mm-sized pixel, 48 bits color), images of the abdomen were selected, and examined to identify lymph nodes and nearby structures. 34 structures (9 in digestive system; 1 in urinary system; 2 in cardiovascular system; 22 in lymphatic system) were segmented on the sectioned images. Based on the sectioned and segmented images, volume and surface models were produced. RESULTS: Among the known 28 lymph node stations, 21 stations were identified through location, size, and color of normal and abnormal structures in the sectioned images and 3D models. Two near the splenic artery could not be separated from the cancer tissue, and the remaining five were not clearly identified. In the surface models, the shape and location of lymph node stations could be confirmed with nearby structures. CONCLUSION: The lymph node stations relevant to pancreatic cancer can be anatomically understood by using the sectioned images and 3D models which contain true color and high resolution.

Advanced-sectioned images obtained by microsectioning of the entire male body.

Realistic two-dimensional (2D) and three-dimensional (3D) applications for anatomical studies are being developed from true-colored sectioned images. We generated advanced-sectioned images of the entire male body and verified that anatomical structures of both normal and abnormal shapes could be visualized in them. The cadaver was serially sectioned at constant intervals using a cryomacrotome. The sectioned surfaces were photographed using a digital camera to generate horizontal advanced-sectioned images in which normal and abnormal structures were classified. Advanced-sectioned images of the entire male body were generated. The image resolution was 3.3 × 3.3 fold better than that of the first sectioned images obtained in 2002. In the advanced-sectioned images, normal and abnormal structures ranging from microscopic (≥0.06 mm × 0.06 mm; pixel size) to macroscopic (≤473.1 mm × 202 mm; body size) could be identified. Furthermore, the real shapes and actual sites of lung cancer and lymph node enlargement were ascertained in them. Such images will be useful because of their true color and high resolution in digital 2D and 3D applications for gross anatomy and clinical anatomy. In future, we plan to generate new advanced-sectioned images of abnormal cadavers with different diseases for clinical anatomy studies.

The Visible Korean: movable surface models of the hip joint.

PURPOSE: In this study, we presented movable surface models to help medical students understand the multiaxial movements of the hip joint. The secondary objective was to demonstrate a simple method to make movable surface models for other researchers. METHODS: We used 166 surface models of the virtual human, and the commercial software was used for all the processes described in this study. Virtual joints were created for the hip joint of the surface models to simulate realistic movements of the joints. Bone surface models were processed to maintain the original shape of the bones during movement. Muscle surface models were processed to express deformation of the muscle shapes during movement. Next, the muscle and bone surface models were moved over six movements of the hip joint (flexion, extension, abduction, adduction, lateral rotation, and medial rotation). The surface models of these six movements were saved and packaged in a PDF file. RESULTS: The PDF file enabled users to see the stereoscopic shapes of the bones and muscles of the hip joint and to scrutinize the six movements on the X, Y, and Z axes of the joint. CONCLUSION: The movable surface models of the hip joint of this study will be helpful for medical students to learn the multiaxial movements of the hip joint. We expect to develop simulations of other joints that can be used in the education of medical students using the materials and methods described in this study.

Dawn of the Visible Monkey: Segmentation of the Rhesus Monkey for 2D and 3D Applications.

BACKGROUND: To properly utilize the sectioned images in a Visible Monkey dataset, it is essential to segment the images into distinct structures. This segmentation allows the sectioned images to be compiled into two-dimensional or three-dimensional software packages to facilitate anatomy and radiology education, and allows them to be used in experiments involving electromagnetic radiation. The purpose of the present study was to demonstrate the potential of the sectioned images using the segmented images. METHODS: Using sectioned images of a monkey's entire body, 167 structures were segmented using Adobe Photoshop. The segmented images and sectioned images were packaged into the browsing software. Surface models were made from the segmented images using Mimics. Volume models were made from the sectioned images and segmented images using MRIcroGL. RESULTS: In total, 839 segmented images of 167 structures in the entire body of a monkey were produced at 0.5-mm intervals (pixel size, 0.024 mm; resolution, 8,688 × 5,792; color depth, 24-bit color; BMP format). Using the browsing software, the sectioned images and segmented images were able to be observed continuously and magnified along with the names of the structures. The surface models of PDF file were able to be handled freely using Adobe Reader. In the surface models, the space information of all segmented structures was able to be identified using Sim4Life. On MRIcroGL, the volume model was able to be browsed and sectioned at any angle with real color. CONCLUSION: Browsing software, surface models, and volume models are able to be produced based on the segmentation of the sectioned images. These will be helpful for students and researchers studying monkey anatomy and radiology, as well as for biophysicists examining the effects of electromagnetic radiation.

A comprehensive review of the mental spine.

Clinical case reports and research regarding the mental spines and their associated structures create a detailed picture of the floor of the mouth for assessment during clinical treatment. This compilation of information covers the mental spines, the attached geniohyoid and genioglossus muscles, the lingual foramina, and the veins and arteries of the jaw and floor of the mouth. It is important to consider the variations in the mental spines for oral and maxillofacial treatment involving the mandible. Differences in anatomy of the mental spine, including their number, location, and size, can impact diagnosis and treatment approaches.

Novel Muscle in Infraspinous Fossa.

The infraspinatus muscle (IS) makes a minor contribution to lateral rotation of the arm but mainly serves to stabilize the glenohumeral (GH) joint as part of the rotator cuff. Although reports of variations in the rotator cuff muscles have been documented previously, specific discussions of IS variants are lacking. In this report, we present a novel case of an accessory muscle in the infraspinous fossa and its relationship to the IS, which was normally located. We describe the observed physical features of the muscles and their innervation patterns.

Identification of cranial nerve ganglia using sectioned images and three-dimensional models of a cadaver.

Background: Cranial nerve ganglia, which are prone to viral infections and tumors, are located deep in the head, so their detailed anatomy is difficult to understand using conventional cadaver dissection. For locating the small ganglia in medical images, their sectional anatomy should be learned by medical students and doctors. The purpose of this study is to elucidate cranial ganglia anatomy using sectioned images and three-dimensional (3D) models of a cadaver. Methods: One thousand two hundred and forty-six sectioned images of a male cadaver were examined to identify the cranial nerve ganglia. Using the real color sectioned images, real color volume model having a voxel size of 0.4 × 0.4 × 0.4 mm was produced. Results: The sectioned images and 3D models can be downloaded for free from a webpage, anatomy.dongguk.ac.kr/ganglia. On the images and model, all the cranial nerve ganglia and their whole course were identified. In case of the facial nerve, the geniculate, pterygopalatine, and submandibular ganglia were clearly identified. In case of the glossopharyngeal nerve, the superior, inferior, and otic ganglia were found. Thanks to the high resolution and real color of the sectioned images and volume models, detailed observation of the ganglia was possible. Since the volume models can be cut both in orthogonal planes and oblique planes, advanced sectional anatomy of the ganglia can be explained concretely. Conclusions: The sectioned images and 3D models will be helpful resources for understanding cranial nerve ganglia anatomy, for performing related surgical procedures.

A Simple and Consistent Rule for Easy Learning of Neuroanatomy: Three Neurons of Afferent Nerves / Una Regla Simple y Consistente para Facilitar el Aprendizaje de la Neuroanatomía: Tres Neuronas de los Nervios Aferentes

SUMMARY: Many students regard neuroanatomy as a terrifying subject due to the complicated neuronal connections. Purpose of this research was to promote the easy and logical learning of neuroanatomy by systematizing a rule "three neurons of afferent nerves." The rule, in which the second neuron decussates and reaches the thalamus, was applied to as many structures as possible. The three neurons are drawn in a constant pattern to intuitively demonstrate the rule. The rule could be applied not only to the spinothalamic tract, medial lemniscus pathway, sensory cranial nerves (visual pathway, trigeminothalamic tract, taste pathway, and auditory pathway) and ascending reticular activating system, but also to the pontocerebellum (afferent to cerebrum), basal nuclei (direct pathway), and limbic system (medial limbic circuit). Exceptionally, some afferent nerves do not exactly follow the suggested rule. This simple rule, which corresponds to many pathways of the neuroanatomy, is expected to make the learning by novice students easier.

Muchos estudiantes consideran la neuroanatomía como un tema aterrador debido a las complicadas conexiones neuronales. El propósito de esta investigación fue promover el aprendizaje fácil y lógico de la neuroanatomía mediante la sistematización de una regla "tres neuronas de los nervios aferentes". La regla, en la que la segunda neurona se decusa y llega al tálamo, se aplicó a todas las estructuras cuando esto fue posible. Las tres neuronas se dibujan en un patrón constante para demostrar la regla intuitivamente. La regla podría aplicarse no solo al tracto espinotalámico, la vía del lemnisco medial, los nervios craneales sensoriales (vía visual, tracto trigeminotalámico, vía gustativa y vía auditiva) y el sistema de activación reticular ascendente, sino también al pontocerebelo (aferente al cerebro), núcleos basales (vía directa) y sistema límbico (circuito límbico medial). Excepcionalmente, algunos nervios aferentes no siguen exactamente la regla sugerida. Se espera que esta simple regla, que corresponde a muchas vías de la neuroanatomía, facilite el aprendizaje de los estudiantes principiantes.

Movable surface models of hand joints using visible korean / Modelos de superficies móviles de articulaciones de manos utilizando visible Korean

SUMMARY: The human hand can make precise movements utilizing several joints of various articular types. To understand hand movements more accurately, it is essential to view the actual movements of bones and muscles considering the X, Y, and Z axes in the joints. This study aimed to investigate the joint movements in a hand using movable surface models, including these axes. These movable surface models of the hand will improve medical students' understanding of hand movements around the joints. To achieve this aim, 70 surface models were adopted from a Visible Korean model. Using Maya software, 20 virtual joints with X, Y, and Z axes included nine distal and proximal interphalangeal joints, five metacarpophalangeal joints, five carpometacarpal joints, and one wrist joint were created. Bone surface models were elaborately polished to maintain their original shape during movement. Muscle surface models were also processed to display the deformation of the muscle shape during movement. The surface models of the hand joints were moved by virtual control of the joints. We saved 87 movable surface models of the hand, including bones, muscles, and joint axes in stereolithography format, and compiled a Portable Document Format (PDF) file. Using the PDF file, the joint movements in a hand could be observed considering the X, Y, and Z axes alongside the stereoscopic shapes of the bones and muscles. These movable surface models of the hand will improve medical students' understanding of hand movements around the joints.

RESUMEN: La mano humana puede realizar movimientos precisos utilizando varias articulaciones de diferentes tipos articulares. Para comprender los movimientos de las manos con mayor precisión, es esencial ver los movimientos reales de los huesos y los músculos considerando los ejes X, Y y Z de las articulaciones. Este estudio tuvo como objetivo investigar los movimientos articulares en una mano utilizando modelos de superficies móviles, incluidos estos ejes. Estos modelos de superficie móvil de la mano mejorarán la comprensión de los estudiantes de medicina de los movimientos de la mano alrededor de las articulaciones. Para lograr este objetivo, se adoptaron 70 modelos de superficie de un modelo coreano visible. Con el software Maya, se crearon 20 articulaciones virtuales con ejes X, Y y Z que incluyeron nueve articulaciones interfalángicas distales y proximales, cinco articulaciones metacarpofalángicas, cinco articulaciones carpometacarpianas y una articulación de muñeca. Los modelos de superficie ósea se pulieron minuciosamente para mantener su forma original durante el movimiento. También se procesaron modelos de superficie muscular para mostrar la deformación de la forma del músculo durante el movimiento. Los modelos de superficie de las articulaciones de las manos se movieron mediante el control virtual de las articulaciones. Guardamos 87 modelos de superficies móviles de la mano, incluidos huesos, músculos y ejes articulares en formato de estereolitografía, y compilamos un archivo en formato de documento portátil (PDF). Usando el archivo PDF, los movimientos de las articulaciones en una mano se pueden observar considerando los ejes X, Y y Z junto con las formas estereoscópicas de los huesos y músculos. Estos modelos de superficie móvil de la mano mejorarán la comprensión de los estudiantes de medicina sobre los movimientos de la mano alrededor de las articulaciones.

Effects of open board lecture videos on anatomy / Efectos de los videos de conferencias de tablero abierto sobre anatomía

SUMMARY: COVID-19 has forced anatomists to perform non-face-to-face education using lecture videos. A Korean anatomist has given (white and black) board lectures and distributed lecture videos to the public for many years. This study was to verify the effects of open board lecture videos in the anatomy field. A questionnaire survey was carried out with the help of medical students who were exposed to the board lecture videos. The video provider uploaded the lecture videos on YouTube, where the viewing numbers were counted. At a medical school where the video provider belonged, the students mainly watched the lecture videos before the anatomy class. The watching hours of the lecture videos were related to the written examination scores. Students gave positive and negative comments on the board lectures. At the other two medical schools, students partly watched the lecture videos regardless of the teacher who delivered the lectures. The results suggested that students understood the board lectures themselves. On YouTube, the lecture videos were viewed by approximately 1,000 students. This paper introduces the desirable aspects of open board lecture videos on anatomy. The videos could enhance the quality of both students and teacher.

RESUMEN: COVID-19 ha obligado a los anatomistas a realizar una enseñanza no presencial mediante videos de conferencias. Un anatomista coreano ha impartido conferencias (en blanco y negro) y ha distribuido videos de conferencias al público durante muchos años. El objetivo de este estudio fue verificar los efectos de los videos de conferencias de pizarra abierta en el campo de la anatomía. Se llevó a cabo una encuesta con la ayuda de estudiantes de medicina que habían sido expuestos a los videos de conferencias de la pizarra. El proveedor de videos subió los videos de las conferencias a YouTube, donde se contabilizó el número de visualizaciones. En una facultad de medicina a la que pertenecía el proveedor de videos, los estudiantes vieron principalmente los videos de conferencias antes de la clase de anatomía. Las horas de revisión de los vídeos de las conferencias se relacionaron con las puntuaciones de los exámenes escritos. Los estudiantes dieron comentarios positivos y negativos sobre las conferencias de la pizarra. En las otras dos facultades de medicina, los estudiantes vieron parcialmente los videos de las clases, independientemente del profesor que las impartiera. Los resultados sugerían que los estudiantes entendieron las conferencias de la pizarra por sí mismos. En YouTube, los videos de las conferencias fueron vistos por aproximadamente 1000 estudiantes. Este artículo presenta los aspectos deseables de los videos de conferencias abiertas sobre anatomía. Los videos podrían mejorar la calidad tanto de los estudiantes como del profesor.