Medical education for millennials: How anatomists are doing it right.

Millennial students born between 1980 and 1999 are currently the most prevalent generation in medical schools. Understanding this generation of inspiring yet challenging learners is key to satisfying instructional interaction. Effective strategies for teaching millennial learners can be summarized with 5 R's: ensuring a relaxed learning environment, building rapport with learners, highlighting the relevance and rationale of learning objectives and assessments, and implementing research-based educational methods. These strategies are exemplified by anatomists who relate (through platforms that encourage team-based learning in a relaxed environment), resonate (by highlighting the relevance and rationale of basic science learning objectives and feedback strategies), and innovate (by adopting cutting edge, research-proven technologies) within their curricula. Anatomists lead the way in effectively engaging, teaching and evaluating Millennial medical students in the 21st century. Broad application of these principles by other medical educators can further enhance Millennial education. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.

Increased Curvature of the Tentorium Cerebelli in Idiopathic Intracranial Hypertension.

BACKGROUND AND PURPOSE: Transverse sinus effacement is detectable on MRV examinations in almost all patients with idiopathic intracranial hypertension. This effacement of the transverse sinus is presumed to be mediated by elevation of intracranial pressure, resulting in compression and inward collapse of the dural margins of the sinus. We sought to establish whether supratentorial broad-based downward deformity of the tentorium might explain transverse sinus effacement in idiopathic intracranial hypertension. MATERIALS AND METHODS: MRV examinations of 53 adult patients with idiopathic intracranial hypertension were reviewed retrospectively and compared with 58 contemporaneously acquired controls. The curvature of the tentorium with reference to a line connecting the transverse sinus laterally with the confluence of the tentorial leaves medially was calculated as a segment of a circle. The height and area of the segment and the angle subtended by the midpoint of the tentorium from the falx were calculated. RESULTS: The height and area of the segment described by the chord connecting the transverse sinus with the apex of the tentorial confluence and subtended midtentorial angle were greater in the idiopathic intracranial hypertension group; this finding supports the hypothesis that increased tentorial bowing is present in idiopathic intracranial hypertension. CONCLUSIONS: Increased bowing of the tentorium in patients with idiopathic intracranial hypertension compared with controls is a new observation, lending itself to new hypotheses on the nature and localization of elevated intracranial pressure in idiopathic intracranial hypertension. Bowing of the tentorium may play a part in distorting the contour of the transverse sinuses, resulting, at least in part, in the effacement of the transverse sinuses in idiopathic intracranial hypertension.

Flexibility of experimental alumina/feldspar and SR ADORO dental composites.

INTRODUCTION: Flexure of a dental composite can be detrimental to the success of a restoration. Flexibility considerations are thus important when comparing dental materials to optimize the success of resin restorations. AIMS AND OBJECTIVES: Flexibility of 5.6 x 18.0 x 2.0 mm3 experimental alumina/feldspar and SR ADORO dental composites specimens were compared. It was hypothesized that alumina/feldspar composites would be less flexible under a load than SR ADORO composites and that the flexibility would decrease significantly as the feldspar content was increased. METHODS: Alumina was chemically sintered or bonded with 40%, 50% and 60% feldspar mass, silanized and infiltrated with urethane dimethacrylate (UDMA) to prepare the alumina/feldspar dental restorative composite specimens. Three point bending tests were performed in the Instron 44 machine for flexural comparison to SR ADORO. RESULTS AND CONCLUSIONS: The alumina/feldspar specimens showed lower flexibility (mm displacement) than SR ADORO (p < 0.05). Accurate flexibility comparisons were performed with 5.6 x 18.0 x 2.0 mm3 specimens. Flexibility comparisons performed with 5.6 x 18.0 x 2.0 mm3 specimens indicated that experimental alumina/feldspar dental composites may provide added marginal seal benefit. However confirmation via in vivo function of alumina/feldspar dental composites is recommended.

Pericardiectomy: a functional anatomical perspective for the choice of left anterolateral thoracotomy.

Although pericardiectomy remains an established method for pericardial resection, the choice of surgical approach is not definitive. Within South Africa, surgical referral for tuberculosis-induced chronic constrictive pericarditis has not declined. Anecdotal reports have indicated good operative results that appear to show an association with choice of surgical technique used. This study aimed to provide a functional anatomical perspective for performance and recovery of the heart during pericardiectomy based on anatomical dissection and surgical notes. En bloc specimens were harvested from 16 fresh cadavers and pericardial segments were measured in terms of percentage cover over surface area of the myocardium. Retrospective analysis of 116 surgical reports of pericardiectomy performed over a period of 20 years was conducted. Surgical notes were compared for median sternotomy and anterolateral left thoracotomy. Results from anatomical study indicated that although the anterior pericardium between the phrenic nerves constitutes about 58% of total selected pericardial area, total pericardium accessible over left ventricle from that approach was only 26%. When orientated in left anterolateral position, total accessible area of left ventricular pericardium was 37%. Standard deviations were found to be comparable. Means were significantly different, indicating that the left anterolateral approach allows wider access to the left ventricle. This paper provides a functional anatomical perspective for the choice of left anterolateral thoracotomy as a surgical approach for pericardiectomy.

Perceptions of problem-based learning (PBL) group effectiveness in a socially-culturally diverse medical student population.

INTRODUCTION: A key aspect of the success of a PBL curriculum is the effective implementation of its small group tutorials. Diversity among students participating in tutorials may affect the effectiveness of the tutorials and may require different implementation strategies. AIMS: To determine how students from diverse backgrounds perceive the effectiveness of the processes and content of the PBL tutorials. This study also aims to explore the relationship between students' perceptions of their PBL tutorials and their gender, age, language, prior educational training, and secondary schooling. MATERIALS/METHODS: Data were survey results from 244 first-year student-respondents at the Nelson Mandela School of Medicine at the University of KwaZulu-Natal in South Africa. Exploratory factor analysis was conducted to verify scale constructs in the questionnaire. Relationships between independent and dependent variables were investigated in an analysis of variance. RESULTS: The average scores for the items measured varied between 3.3 and 3.8 (scale value 1 indicated negative regard and 5 indicated positive regard). Among process measures, approximately two-thirds of students felt that learning in a group was neither frustrating nor stressful and that they enjoyed learning how to work with students from different social and cultural backgrounds. Among content measures, 80% of the students felt that they learned to work successfully with students from different social and cultural groups and 77% felt that they benefited from the input of other group members. Mean ratings on these measures did not vary with students' gender, age, first language, prior educational training, and the types of schools they had previously attended. DISCUSSION AND CONCLUSION: Medical students of the University of KwaZulu-Natal, regardless of their backgrounds, generally have positive perceptions of small group learning. These findings support previous studies in highlighting the role that small group tutorials can play in overcoming cultural barriers and promoting unity and collaborative learning within diverse student groups.

Wear and flexural strength comparisons of alumina/feldspar resin infiltrated dental composites.

INTRODUCTION: Incorporating a feldspar chemical bond between alumina filler particles is expected to increase the wear-resistant and flexural strength properties. AIMS AND OBJECTIVES: An investigation was carried out to evaluate the influence of the feldspar chemical bonding between alumina filler particles on wear and flexural strength of experimental alumina/feldspar dental composites. It was hypothesized that wear resistance and flexural strength would be significantly increased with increased feldspar mass. METHODS: Alumina was chemically sintered and bonded with 30% and 60% feldspar mass, silanized and infiltrated with UDMA resin to prepare the dental restorative composite material. RESULTS AND CONCLUSIONS: Higher wear-resistant characteristics resulted with increased feldspar mass of up to 60% (p < 0.05). Higher flexural strength characteristics resulted as the feldspar mass was increased up to 60% (p > 0.05). Feldspar chemical bonding between the alumina particles may improve on the wear-resistance and flexural strength of alumina/feldspar composites.

Dental composite materials: highlighting the problem of wear for posterior restorations.

Manufacturers of dental composites promote their products as having ideal wear resistant characteristics. Evaluation of the problems that persist with wear of dental composites is made. Recommendations for further research involving wear resistance of dental composite materials are provided. This article provides a review of English, peer-reviewed literature involving wear resistance of dental composite materials conducted through ScienceDirect and hand searched data bases between 1994 and 2006.

Bilateral origin of the internal thoracic artery from the third part of the subclavian artery: a case report.

The routine use of the internal thoracic artery (ITA) as a conduit in coronary artery bypass grafting surgery has highlighted the need to appreciate this vessel's anatomic variations. The usual origin of this vessel is from the first part of the subclavian artery, occasionally from the second and rarely from the third. Henriques-Pino and Prates described a unilateral origin from the third part on the left and Vorster et al on the right. Our cadaveric case report presents an unusual bilateral origin of the ITA arising from the third part of the subclavian artery in a 25-year-old Black South African female. The ITA arose from the ventral aspect, 7.3 cm on the right side and 8.5 cm on the left side from the origin of the subclavian artery, and inclined acutely inferiorly and medially, anterior to the distal attachment of the scalenus anterior m., followed the inner border of the first rib for a short distance and, thereafter, continued its usual course in the thorax. This appears to be the first case report presenting a bilateral origin of the ITA from the third part of the subclavian artery.

Lithopedion: a case report.

An 80-year-old Black, South African woman presented in the outpatient department with severe abdominal pain. Ultrasound examination revealed a large echogenic mass (20 x 20 cm) in the right upper quadrant. An abdominal x-ray demonstrated the skeleton of a fully developed extrauterine fetus. It is presumed from the patient's history that this fetus was present for at least 40 years. Radiography revealed a fetus shrouded in a mantle of calcification. The fetus was hyper-flexed with other signs of "intrauterine" death. Fetal dentition charts dated the fetus at 34 weeks, the epiphyses being obscured by extensive calcification. In addition to subcutaneous calcification there was extensive visceral and intracranial calcification.

Clinical significance of internal thoracic artery morphometry and inter-ethnic differences.

The internal thoracic artery (ITA) is used extensively for coronary revascularisation. Clinical observations suggest an inter-ethnic difference in ITA morphometry between Indians and whites presenting for coronary artery bypass surgery. However, accurate morphometric data comparing these ethnic groups were not available. This study analyses the morphometry of the left and right ITAs in 60 cadavers (43 blacks, 9 whites, 8 Indians). The lengths of the arteries were measured and the external diameters were recorded at the origin of the 1st, 4th and 6th costal cartilages. Significant differences in length and diameter on the right and left sides between ethnic groups were demonstrated. In particular, these differences were marked between the white and Indian groups. Clinically, these differences can be so marked that in some instances the left ITA in Indian patients is so small at the distal point of take-down as to be unsuitable for use as an arterial conduit. This is one of the reasons that has prompted the use of the ITA as a composite graft. Our study appears to be the first to highlight this inter-ethnic difference and to support the clinical impression.

Origin and incidence of xiphoid branch of the internal thoracic artery.

The study presents the incidence of a variant terminal branch of the internal thoracic artery (ITA). The ITA's were cannulated in situ, injected with coloured latex and dissected together with its branches in 62 cadavers. Unlike the usual termination of the ITA bifurcating into the musculophrenic and superior epigastric arteries, this third branch arose from the medial border of the ITA at the level of the 6th costal cartilage. As it descends it inclines medially towards the angle between the xiphoid process and the 7th costal cartilage, giving off 2 or 3 fine branches to the lower sternum. It then passes deep to this angle and can be observed on the anterior surface of the xiphoid process, terminating in fine branches distributed to the inferior aspect of the xiphoid cartilage. It is proposed that this branch at the "trifurcation" of the ITA be termed the xiphoid branch. This branch was noted in 61.3%. An incidence of 30.7% was seen on the right and 21% on the left with bilateral presence in 9.7%. The xiphoid branch contributes to the supply to the lower sternal region and may be of special importance when the collateral supply to the region is compromised in the event of the internal thoracic or superior epigastric artery damage or when used as a conduit in coronary artery by-pass grafts.

Morphometry of the internal thoracic arteries.

The surgical significance of the internal thoracic arteries (ITA's) in procedures such as coronary artery bypass grafting, transverse rectus abdominis myocutaneous flaps and minimal incision direct coronary artery bypass surgery is well recognised. However, the detailed morphometry of these vessels is not well documented. This study aimed to detail the morphometry of the ITA's. Morphometric analysis of these vessels from post mortem en-bloc specimens, consisting of aortic arch, great vessels and ITA's with anterior chest wall was conducted on 62 adults. The mean lengths and diameters of the ITA's at the origin, costal cartilage levels and termination were: length of the right ITA, 18.05 +/- 0.6 cm and the left, 18.085 +/- 0.6 cm. The average diameters recorded at the origin, first costal cartilage, fourth costal cartilage and termination were: right: 3.24 +/- 0.5 mm; 2.85 +/- 0.4 mm; 2.33 +/- 0.6 mm; 1.98 +/- 0.2 mm and left: 3.05 +/- 0.4 mm, 2.67 +/- 0.3 mm; 2.22 +/- 0.3 mm; 1.92 +/- 0.2 mm respectively. Morphometry of the ITA's are detailed. There was no significant difference in length between right and left ITA's although differences between the race groups were demonstrated. Significant differences in diameters in sides and race exist.