- ItemAccurate arterial path length estimation for pulse wave velocity calculation in growing children and adolescents(Gates Open Research, 2021-05) Witbooi, Lee-Roy C.; Page, Ben; Pitcher, Richard D.; Innes, SteveBackground: Most adult cardiovascular disease begins in childhood. Given the burgeoning obesity pandemic in children worldwide, there is a need for precise and scalable surveillance methods to detect subclinical cardiovascular disease in children and adolescents. Early detection allows early intervention and intensified primary prevention strategies in affected individuals. Carotid-femoral pulse wave velocity (PWV) directly measures arterial wall stiffness, an early feature of atherosclerosis. Calculation of PWV in growing children requires an accurate estimation of the true distance travelled by the aorto-femoral pressure wave, using surface anatomy landmarks. However, a variety of methods are used to estimate this distance, and these have not previously been investigated in growing children and adolescents. We sought to investigate this by comparing true arterial path length measured on computerized tomography (CT) scans, with a variety of estimations based on surface anatomy landmarks. Methods: Arterial path lengths were measured using multi-planar reformation (MPR) imaging software. These measurements were then compared with the surface anatomy measurements obtained using the same MPR imaging software. The fidelity of a variety of arterial path length estimation methods was tested. Results: The surface anatomy distance between the suprasternal notch and the angle of the mandible (PWV recording site in the neck), should be adjusted using the formula y=4.791+(1.0534*x). This value subtracted from the unadjusted distance from the suprasternal notch to the umbilicus, through the mid-inguinal crease to the femoral PWV recording site, provides the simplest reliable approximation of true intraluminal distance travelled. Conclusions: There is high correlation between the surface anatomy distances and the arterial path lengths they represent; however, these are not equal. Most surface anatomy measurements require adjustment using the formulae that we have provided, to accurately estimate the true distance travelled by the pulse wave.
- ItemThe inferior intercavernous sinus : an anatomical study with application to trans-sphenoidal approaches to the pituitary gland(Elsevier, 2020-06) Wahl, Lauren; Lockwood, Joseph D.; Keet, Kerri; Henry, Brandon Michael; Gielecki, Jerzy; Iwanaga, Joe; Bui, C. J.; Dumont, Aaron S.; Tubbs, R. ShaneObjectives: The inferior intercavernous sinus is located below the pituitary gland in the sella turcica. Its presence has been controversial among anatomists because it is not always found on radiological imaging or during cadaveric dissections; however, it is becoming a better-known structure in the neurosurgical and radiological fields, specifically with respect to transsphenoidal surgery. Therefore, the present study was performed to better elucidate this structure at the skull base. Patients and methods: Fifty adult, latex injected cadavers underwent dissection. The presence or absence of the inferior cavernous sinus was evaluated and when present, measurements of its width and length were made. Its connections with other intradural venous sinuses were also documented. Results: An inferior intercavernous sinus was identified in 26 % of specimens. In all specimens, it communicated with the left and right cavernous sinus. The average width and length were 3 mm and 9.5 mm, respectively. In the sagittal plane, the inferior intercavernous sinus was positioned anteriorly in 31 %, at the nadir of the sella turcica in 38 %, and slightly posterior to the nadir of the sella turcica in 31 %. In two specimens (15.4 %), the sinus was plexiform in its shape. In one specimen a diploic vein connected the basilar venous plexus to the inferior intercavernous sinus on its deep surface. Conclusion: An improved understanding of the variable anatomy of the inferior intercavernous sinus is important in pathological, surgical, and radiological cases.
- ItemTrace element concentration changes in brain tumors : a review(American Association for Anatomy, 2020-05) Cilliers, Karen; Muller, Christo J. F.; Page, Benedict J.Trace elements have been implicated in cancer, since the levels differ between cancerous and noncancerous tissue, different cancer types, and different malignancy grades. However, few studies have been conducted on trace element concentrations in brain tumors. Thus, this study aims to review the available literature on trace element changes related to brain tumors, and to identify gaps in the literature. A literature search was done on Google Scholar and PubMed from their start date to January 2018, using terms related to trace element concentration and brain tumors. All brain tumor types were included, and articles could be published in any year. From this search, only 11 articles on this topic could be found. Tumors had significantly higher concentrations of arsenic, thorium, lanthanum, lutetium, cerium, and gadolinium compared to control brain samples. Compared to adjacent tissue, tumor tissue indicated increased magnesium, decreased copper, and contradicting results for zinc. Furthermore, the higher the malignancy grade, the lower the calcium, cadmium, iron, phosphorus and sulfur concentration, and the higher the mercury, manganese, lead, and zinc concentrations. In conclusion, altered trace element levels differ amongst different tumor types, as well as malignancy grades. Consequently, it is impossible to compare data from these studies, and available data are still considerably inconclusive. Ideally, future studies should have a sufficient samples size, compare different tumor types, and compare tumors with adjacent healthy tissue as well as with samples from unaffected matched brains. Anat Rec, 303:1293-1299, 2020. © 2019 American Association for Anatomy.
- ItemCongenital Anomalies of the Tracheobronchial Tree: A Meta-Analysis and Clinical Considerations(2020-11) Wong, Linda M; Cheruiyot, Isaac; Santos de Oliveira, Maria HelenaBackground The aim of this study was to determine the prevalence and anatomical features of major tracheobronchial anomalies (mTBAs). Methods Major electronic databases were systematically searched to identify eligible studies. Data were extracted and pooled into a meta-analysis. The primary outcome was the prevalence of mTBAs, specifically tracheal bronchus (TB) and accessory cardiac bronchus (ACB). Secondary outcomes included the origin and types of TB and ACB. Results A total of 27 studies (n=119,695 patients) were included. A TB was present in 0.99% (95% CI 0.67-1.37) of patients, while an ACB was present in 0.14% (95% CI 0.09- 0.20). The overall prevalence of TB was higher in imaging than in operative studies (1.81% vs 0.82%). It was also higher in pediatric (2.55%) than in adult studies (0.50%). Patients with other congenital anomalies were 15 times more likely to have a TB (OR=14.89; 95% CI 7.09-31.22). The most common origin of TBs was from the trachea (81.42%), primarily from the right side (96.43%). The most common origin of ACBs was from the intermediate bronchus (74.32%). ACBs terminated as blind-ending diverticulum in two-thirds of cases. Conclusions mTBAs are present in approximately 1% of the population, although the prevalence is higher in pediatric patients and those with accompanying congenital anomalies. Although rare, mTBAs can be associated with significant respiratory morbidities, and present challenges during airway management in surgical and critical care patients. Establishing a pre-operative diagnosis of these variations is essential for planning and implementing an appropriate airway management strategy to minimize attendant complications.
- ItemOpening the floor for discussion : a perspective on how scholars perceive attitudes to science in policymaking in South Africa(ASSAf, 2021-01-29) Czachur, Molly V.; Todd, Melvi; Goncalves Loureiro, Taina; Azam, James M.; Nyeleka, Siphokazi; Alblas, Amanda; Davies, Sarah J.Policymakers are a vital group with whom scientific research should be communicated, especially when the reason for many research projects is linked to relevance for socio-political and economic management. Science communication has a vital role in transforming research into policy, and a core element of this process is understanding the target group, namely policymakers. Science and policy influence each other deeply, so researchers and policymakers should improve their understanding of each other and of the processes involved in both fields in order to better collaborate. Accordingly, an in-depth understanding of how scholars perceive policymakers is a precondition for scientists to achieve any desired management and policy impacts. In December 2019, six researchers and one research manager from Stellenbosch University, South Africa, gathered to discuss their understanding of policymakers. The discussion was part of a Science Communication Masterclass hosted by the South African Research Chair in Science Communication and Econnect Communication, Australia. The purpose of the group discussion was to develop a science communication strategy that would enhance the sharing of scientific research outputs with policymakers in South Africa. We explored five questions to help us record our perception of policymakers: (1) Who do we think the policymakers are? (2) How do we think that policymakers perceive research? (3) What concerns do we believe that policymakers have about research? (4) What information do we think policymakers are interested in? (5) What forms of communication do we think policymakers prefer? This Commentary presents our view on how we think researchers perceive policymakers, as discussed in the Science Communication Masterclass. We hope to initiate a discussion around science communication with policymakers, and improve current practices.