What is the real cardiac anatomy?

The heart is a remarkably complex organ. Teaching its details to medical students and clinical trainees can be very difficult. Despite the complexity, accurate recognition of these details is a pre-requisite for the subsequent understanding of clinical cardiologists and cardiac surgeons. A recent publication promoted the benefits of virtual reconstructions in facilitating the initial understanding achieved by medical students. If such teaching is to achieve its greatest value, the datasets used to provide the virtual images should themselves be anatomically accurate. They should also take note of a basic rule of human anatomy, namely that components of all organs should be described as they are normally situated within the body. It is almost universal at present for textbooks of anatomy to illustrate the heart as if removed from the body and positioned on its apex, the so-called Valentine situation. In the years prior to the emergence of interventional techniques to treat cardiac diseases, this approach was of limited significance. Nowadays, therapeutic interventions are commonplace worldwide. Advances in three-dimensional imaging technology, furthermore, now mean that the separate components of the heart can readily be segmented, and then shown in attitudinally appropriate fashion. In this review, we demonstrate how such virtual dissection of computed tomographic datasets in attitudinally appropriate fashion reveals the true details of cardiac anatomy. The virtual approach to teaching the arrangement of the cardiac components has much to commend it. If it is to be used, nonetheless, the anatomical details on which the reconstructions are based must be accurate. Clin. Anat. 32:288-309, 2019. © 2019 The Authors. Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.

Posterior approach to kidney dissection: An old surgical approach for integrated medical curricula.

Integrated medical curricular changes are altering the historical regional anatomy approach to abdominal dissection. The renal system is linked physiologically and biochemically to the cardiovascular and respiratory systems; yet, anatomists often approach the urinary system as part of the abdomen and pelvic regions. As part of an integrated curriculum, the renal system must be covered relatively quickly after the thorax in the cadaver laboratory, often without the opportunity to fully appreciate the rest of the abdominal contents. This article provides dissection instructions that follow one of the historical surgical approaches for nephrectomy, including preservation of the posterior abdominal wall neurovasclature. Dissection procedures were developed for first-year medical students, intending this posterior approach to the kidneys to be their first introduction to the renal system. It has been successfully implemented with the first-year medical students at the University of New England, College of Osteopathic Medicine. Utilizing this posterior approach to the kidney enabled the study of the anatomy of the kidneys, suprarenal glands, and renal vessels, as well as the muscles of the lumbar spine, while maintaining the integrity of the anterior abdominal wall and peritoneal cavity for future gastrointestinal and reproductive system-based dissections.

Curriculum integration = course disintegration: what does this mean for anatomy?

Many basic scientists including anatomists are currently involved in decisions related to revisions of the undergraduate medical curriculum. Integration is a common theme in many of these decisions. As described by Harden, integration can occur along a multistep continuum from independent, discipline-based courses to a completely interdisciplinary curriculum. For anatomy, each derivative of curricular integration can be shown to involve progressive disruptions of the temporal and topographical relationship between organ systems in a body region, of the temporal relationship with other courses in a harmonized curriculum, and of the relationships between components of organ systems when integration is implemented in thematic curricula. Drawing from our experience teaching in various types of integrated medical curricula, we encourage readers to proceed cautiously with their curricular decisions because each one can have gains and losses that may impact learning in the new format.

Computerized grading of anatomy laboratory practical examinations.

At the Medical College of Wisconsin, a procedure was developed to allow computerized grading and grade reporting of laboratory practical examinations in the Clinical Human Anatomy course. At the start of the course, first year medical students were given four Lists of Structures. On these lists, numbered items were arranged alphabetically; the items were anatomical structures that could be tagged on a given lab practical examination. Each lab exam featured an anatomy laboratory component and a computer laboratory component. For the anatomy lab component, students moved from one question station to another at timed intervals and identified tagged anatomical structures. As students identified a tagged structure, they referred to a copy of the list (provided with their answer sheet) and wrote the number corresponding to the structure on their answer sheet. Immediately after the anatomy lab component, students were escorted to a computer instruction laboratory where they typed their answer numbers into a secured testing component of a learning management system that recorded their answers for automatic grading. After a brief review of examination scores and item analysis by faculty, exam scores were reported to students electronically. Adding this brief computer component to each lab exam greatly reduced faculty grading time, reduced grading errors and provided faster performance feedback for students without changing overall student performance.

High frequency ultrasound imaging of the growth and development of the normal chick embryo.

The purpose of this study is to delineate with high frequency ultrasound imaging the normal growth and development of the chick embryo throughout its incubation period. White Leghorn chick embryos were imaged through an opening in the egg air cell from incubation day 0-19 (Hamburger & Hamilton stage 1-45) using a 13 MHz clinical high frequency linear small parts transducer. Multiple anatomic growth parameters were measured. Normal growth was confirmed with Hamburger and Hamilton staging. A timeline was constructed showing when each anatomic growth parameter could be visualized. Means and standard deviations of each parameter were plotted against incubation days studied to create nomograms and numerical tables of normal growth and development of the chick embryo. With this set of data, abnormal growth and development of the chick embryo can now be assessed.

Preliminary investigation of the use of high frequency ultrasound imaging in the chick embryo.

BACKGROUND: The purpose of this study was to investigate the feasibility of using high frequency ultrasound to study the chick embryo in a noninvasive and longitudinal fashion. METHODS: A total of 10 SPF White Leghorn chick embryos (GDs 11-17; Hamburger and Hamilton stage 37-43) were consecutively examined with a GE Logiq 400 ProSeries ultrasound unit using an 11-MHz small parts ultrasound probe. Access for ultrasound visualization of the embryos was accomplished by opening a 2-3-cm window either in the air cell over the blunt end of the egg or laterally over the embryo-dependent side of the egg. Warmed ultrasound coupling gel was used for imaging, and thermal regulation was maintained with infant heel warmers. The ultrasound images were recorded directly on digital video using a Sony TRV 900 DV camcorder. The images were directly converted to jpeg and mjeg2 files for further analysis. RESULTS: Effective visualization of each embryo was possible on each day of the study period. The embryos were best visualized through the opening made in the air cell at the blunt end of the egg. The extent of the anatomic survey of the chick embryo was dependent upon the position of the embryo in the egg relative to the opening in the air cell. Doppler color flow mapping studies were obtained of the embryonic and extraembryonic circulation. CONCLUSIONS: This preliminary investigation clearly shows the feasibility of high frequency ultrasound imaging to study chick embryo development in a longitudinal and noninvasive fashion. Further studies are presently ongoing regarding earlier embryo development, as well as to determine the stability and dynamics of the methodology.

Pyriform sinus malformations: a cadaveric representation.

BACKGROUND/PURPOSE: The most important aspects in management of pyriform sinus malformations are awareness of the diagnosis, familiarity with the clinical manifestations, and complete surgical excision of the entire tract. Pyriform sinus anomalies are the least common branchial apparatus malformations and present anatomically as sinus tracts with or without cystic dilatation. The clinical presentations can include lateral neck mass, thyroid abscess, suppurative thyroiditis, retropharyngeal abscess, neonatal airway obstruction, and even carcinoma. Recurrent symptoms after surgery suggest incomplete identification and excision of the tract. METHODS: Cadaveric dissections were performed to show both the proposed embryologic course and clinical manifestations of third and fourth branchial apparatus pyriform sinus anomalies. RESULTS: Illustrations and digital camera images of the cadaveric models are presented to explain the course of pyriform sinus fistula tracts. CONCLUSIONS: The authors discuss 3 case presentations of pyriform sinus anomalies with emphasis on their proposed embryologic origin and anatomic basis for surgical management. Surgical excision is the mainstay of therapy. Understanding the embryologic basis for pyriform sinus malformations aids in recognition of the diagnosis despite the myriad of clinical presentations. Laryngoscopy with sinus cannulation facilitates removal of the entire sinus tract with preservation of the recurrent and superior laryngeal nerves.