Anatomy and Histology

Permanent URI for this community

https://scholar.sun.ac.za/handle/10019.1/138

Browse

Now showing 1 - 20 of 58

Accurate 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, Steve
Background: 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.
Accurate estimation of large vessel length in growing children and adolescents for the purpose of pulse wave velocity calculation.
(Stellenbosch : Stellenbosch University, 2018-12) Witbooi, Lee-Roy Cecil; Innes, Steve; Page, Ben; Pitcher, Richard; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
Background Cardiovascular disease is a major cause of death in adults worldwide. Early detection allows for early intervention to prevent vascular events such as strokes, heart attacks, etc. Although these vascular events typically occur in late adulthood, the underlying atherosclerosis often begins during childhood. Early subclinical atherosclerosis can be detected by measuring the elasticity of the large arteries, particularly when performed serially over time. Normally, the elasticity of a healthy aorta helps to slow down the speed of the pressure wave created by contraction of the heart muscle. This is an important way of maintaining smooth laminar blood flow. Atherosclerosis causes the vessel wall to harden and lose elasticity. As the vessel wall hardens, the speed of the pressure wave increases. Pulse wave velocity (PWV) is a sophisticated method of detecting early elasticity changes, and is a preferred non-invasive technique to measure arterial wall stiffness. The velocity calculation requires accurate measurement of both distance travelled and time taken for the pulse wave to travel between two points. The distance used for pulse wave velocity calculation is an approximation of the intraluminal distance travelled by the pulse wave and is estimated by measuring the distance between various surface anatomy landmarks. The expert consensus document on arterial wall stiffness described carotid–femoral PWV as the “gold standard” measurement of arterial wall stiffness, yet there is no consensus on the arterial path length estimation method. A variety of arterial path length estimation methods exist, and this makes inter-study comparison of PWV very difficult. The purpose of the current study was to investigate the most accurate method of estimating the true distance travelled by the aorto-femoral pressure wave. We compared distances between a range of commonly used surface anatomy landmarks, and compared these to the true intraluminal distance measured on multi-planar reformations of archived computerized tomography imaging in children of varying ages. Our findings will allow standardization of PWV calculation in children and allow for inter-study comparisons. Methods Vessel lengths in children (aged 0-18 years) were measured with multi-planar reformation (MPR) imaging software. These measurements were then compared with the surface anatomy measurements also obtained using the MPR imaging software. The comparisons between vessel lengths and surface anatomy distances were performed in segments, since there were no whole body CT scans available on the Picture Archiving and Communication System (PACS) at the research site. Results The surface anatomy measurements from the suprasternal notch to the angle of the mandible (on the right) correlated well with the intraluminal vessel length from the origin of the brachiocephalic trunk to the external carotid at the angle of the mandible (r2=0.92; p<0.0001). The surface anatomy measurements from the suprasternal notch to the midpoint of the right inguinal crease, correlated well with the intraluminal vessel length from the origin of the brachiocephalic trunk to the right femoral artery at the right inguinal ligament (r2=0.98; p<0.0001). The surface anatomy measurements from the suprasternal notch to the xiphisternum, plus the surface distance between xiphisternum and the umbilicus, plus the surface distance between the umbilicus and the midpoint of the right inguinal crease, correlated well with the intraluminal vessel length from the origin of the brachiocephalic trunk to the right femoral artery at the right inguinal ligament (r2=0.97; p<0.0001). The surface anatomy measurement from the suprasternal notch to the xiphisternum, plus the surface distance between the xiphisternum and the midpoint of right inguinal crease, correlated well with the intraluminal vessel length from the origin of the brachiocephalic trunk to the right femoral artery at the right inguinal ligament (r2=0.97; p<0.0001). A regression equation is provided for each set of surface anatomy measurements, allowing further adjustment of measurements to more accurately represent the true intraluminal distance travelled by the pulse wave. Conclusions The surface anatomy distance between the suprasternal notch and the angle of the mandible, subtracted from the distance between the suprasternal notch and mid-inguinal crease, provides the closest approximation of true intraluminal distance travelled and would be the best method to standardize pulse wave velocity calculation in children and adolescents. However, surface anatomy estimations using the xiphisternum and umbilicus as landmarks produced very similar correlations.
Anatomical variation of the carotid bifurcation in a Stellenbosch University cadaver cohort
(Stellenbosch : Stellenbosch University, 2019-04) Dreyer, Rita Liezl; Page, Benedict; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences: Anatomy and Histology.
ENGLISH ABSTRACT: The carotid bifurcation is the point where the common carotid artery bifurcates into the internal and external carotid artery. A precise anatomical knowledge of the carotid bifurcation is required for various medical specialities. The anatomy of the carotid bifurcation influences the risks, location and prognosis of related pathology. Furthermore, the anatomy of the carotid bifurcation affects treatment as it determines which surgical techniques can be used in an area of high risk. The aim of the study was to determine the anatomical variations of the carotid bifurcation in a Stellenbosch cadaver cohort. One hundred and twenty-eight specimens were examined. This research focuses on the height, angle, general structure, and diameters of the carotid bifurcation, as well as the length and diameter of the carotid sinus. The internal anatomical variation of the carotid bifurcation was added as the study progressed. This study used the gonion as the landmark when measuring height. The Stellenbosch cadaver cohort had a high frequency of high bifurcation with the mean distance of 2.12 cm on the right and 2.06 cm on the left. The angle of bifurcation was 18.53° on the right and 20.24° on the left and was smaller than previous reports in the literature, which ranged between 51-67°. Females had a higher bifurcation and larger angle of bifurcation than males. Sex affected the correlation between angle and height of the bifurcation. The general structure correlated with the standard description and was not influenced by other factors pertaining to the carotid bifurcation, sex or age. Kinks were found in the internal and external carotid artery. The diameters of the carotid bifurcation were larger on the left than on the right. The height of the bifurcation did not influence the probability of kinks in this study, contrary to the literature. The diameters of the internal, external and common carotid arteries in addition to the carotid sinus diameter were larger on the left side and in males. The external carotid had the weakest correlation with the other diameters, which was due to the external carotid artery’s embryological origin. The length of the carotid sinus was 1.74 cm on the right and 1.83 cm on the left. The diameters and the length of the carotid sinus was larger in the males. All external variation slightly increased with age over time as the elasticity of arteries decreased. A variation of the flow diverter was observed in 59% of the cadaver cohort. Supplementary flow diverters were a rare abnormality observed in the internal, external and common carotid arteries. The reason for the carotid bifurcation to present with supplementary flow diverters is still up for debate as this has not been observed in living patients; however, a pathological origin was suggested. Folds in the common carotid were observed. Internal anatomical variation was not affected by external variation or age; however, men had a higher probability of presenting with variation. The Stellenbosch cadaver cohort illustrated variations in the carotid bifurcation which was population-specific. Sex influenced various aspects and correlations of the carotid bifurcation, which means discrepancies can occur and should be considered. Further studies on the carotid bifurcation are needed.
The anatomy of seismic signalling: morphological adaptations of the hind limb in drumming and non-drumming African mole-rats (Bathyergidae)
(Stellenbosch : Stellenbosch University, 2021., 2021-03-31) Sahd, Lauren; Kotze, Sanet H.; Bennett, Nigel C.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
ENGLISH ABSTRACT: Hind foot drumming is one of the most common forms of seismic signalling. The family Bathyergidae (African mole-rats) is well known for exhibiting hind foot drumming during courtship and territorial behaviour. Hind foot drumming in bathyergid species arises as a result of the rapid flexion and extension of the hip and knee joints by either a single or alternating hind limbs. While the ecological context of drumming in these species has been well described, the possible morphological adaptations to enable the production of these seismic signals, have yet to be unravelled. Therefore, the primary aim of the present study was to investigate if morphologically discernible adaptations to the hind limb osteology and muscles could be determined in two drumming (Georychus capensis and Bathyergus suillus) and one non-drumming species (Cryptomys hottentotus natalensis) of African mole-rats using a variety of techniques. The gross anatomy of the hind limb was investigated by undertaking detailed dissections to determine the origin and insertion points as well as the innervation of the muscles of the hind limb. Thereafter, 32 muscles were removed from a single limb (with joint angles closest to 90°) for muscle architecture measurements which included belly length, muscle fascicle length, muscle mass and physiological cross-sectional area. The remaining soft tissue was removed from the specimens by maceration to enable the description of the osteology of the hind limb. Additionally, morpho-functional indices were used to morphometrically compare the bones between species. Twenty-one hind limb muscles were selected to undergo muscle fibre typing using myosin heavy chain slow antibody immunohistochemical staining. The amount of positive fibres was quantified to determine the total percentage of slow muscle fibres in each muscle section. Micro computed tomography (CT) scans of contrast enhanced stained specimens were used to determine accurate volumetric measurements of 26 muscles per sample in all three species as well as to assemble three dimensional reconstructions of the musculature of the limbs. Musculus gracilis anticus may play a key role in hind foot drumming as it was the only muscle that was morphologically different between the drummers and non-drummer. In the two drumming species, m. gracilis was a single muscle, whereas it was double in C. h. natalensis. Additionally, it was the only muscle to be significantly different in G. capensis and C. h. natalensis for all muscle architecture parameters analysed. Furthermore, m. gracilis anticus was the only muscle that had a significant difference in the volume as determined by the micro CT scans between the two drumming species and C. h. natalensis. However, the number of slow fibres of m. gracilis anticus was not significantly different between G. capensis and C. h. natalensis. Furthermore, the robust tibias in the drumming species, as indicated by the tibial robustness index, possibly counter the additional biomechanical load caused by the muscles (specifically m. gracilis anticus) involved with hind foot drumming. Thus, it can be concluded that there are distinct morphological adaptations to the osteology and musculature of the two hind foot drumming species.
Ancillary methods to improve diagnostic accuracy of thyroid nodules on fine-needle aspiration cytology smears
(Stellenbosch : University of Stellenbosch, 2007-12) Van Wyk, Christine; Louw, Mercia; Wright, Colleen; University of Stellenbosch. Faculty of Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
Thyroid nodules are a common clinical problem encountered by physicians, surgeons and radiologists who deal with the head and neck region. However, most follicular lesions of the thyroid are benign, so that the indications for surgery should be as accurate as possible. The morphological difficulty on fine-needle aspiration biopsy (FNAB) of reliably distinguishing preoperatively between benign and malignant lesions has led to a search for ancillary methods that can assist with the diagnosis. The aim of the first study was to develop a cytological scoring system to improve diagnostic accuracy of fine-needle aspiration biopsy of papillary carcinomas with special reference to the follicular variant of papillary carcinoma. The objective of the second study was the application of immunodiagnostic markers Galectin-3 and HBME-1 to histology tissue sections and their corresponding fine-needle aspiration cytology smears to assess their value in distinguishing benign from malignant thyroid lesions. In the first study 16 different cytological features such as background, architecture and cellular morphology were quantatively assessed and scored. Only 14 of the 16 variables were statistically significant. The statistical analysis demonstrated that a score ≥ 4 was indicative of a papillary carcinoma with a sensitivity of 96%. A score < 4 suggested a benign multinodular goiter with a specificity of 97%. In the second study Galectin-3 and HBME-1 were applied to histology tissue sections and their corresponding fine-needle aspiration cytology smears. Statistical analyses showed that the sensitivity of immunohistochemistry for diagnosing malignancy was better than the immunocytochemistry, but the specificity of immunocytochemistry was superior. Furthermore the diagnostic accuracy of immunohistochemistry (86%) and immunocytochemistry (88%) using co-expression of these two antibodies was excellent. In this study on immunocytochemistry, papillary carcinomas were clearly identified with a 100% co-expression in the classic and 71% in the follicular variant of papillary carcinoma. For the surgeon the identification of papillary carcinoma is critical, as this determines the extent of surgery. Similary, the confirmation of a non-neoplastic lesion may prevent surgery. In most cases follicular neoplasms, benign or malignant, will usually be excised for histopathology, prior to definite therapy. These studies show that the implementation of ancillary methods such as a scoring system and immunodiagnostic markers can improve the diagnostic accuracy of thyroid fine-needle aspiration biopsies in our laboratory. This may lead to better management of thyroid nodules. However, it is advisable that cytopathologists always take all the clinical features and image analyses into consideration before making a diagnosis.
Anti-ulcerogenic properties of Albuca setosa
(2013-12) Ndebia, E. J.; Tchokonte-Nana, Venant; Umapathy, E.; Tamadjou Tchuen, C. R.; Williams, R. P.; Sewani-Rusike, C. R.; Page, B. J.; Iputo, J. E.; Anatomy and Histology
ENGLISH ABSTRACT: Albuca setosa is a medicinal plant used by Xhosa tribe in the rural area of South Africa for the treatment of wounds, articulation problems, rheumatoid arthritis and digestive disorders. This study aimed to evaluate the healing effect of A. setosa on experimental induced gastric ulcer. The anti- ulcerogenic effects of A. setosa were investigated in male Wistar rats. Gastric ulcer was induced per os using indomethacin (50 mg/kg) and ethanol (2 ml/animal). The ulceration lesion index was calculated for each one of the ulcerated stomach; the macroscopic and histomorphology evaluation were made. In indomethacin-induced gastric ulcers, oral administration of A. setosa significantly inhibited (P<0.01) gastric ulcer formation by 82 and 83% at the dose of 100 and 200 mg/kg, respectively. In ethanol- induced gastric ulcers, A. setosa significantly inhibited (P<0.05) gastric ulcer formation by 39 and 35% at the dose of 100 and 200 mg/kg, respectively. Macroscopic evaluation of ulcerated stomachs of A. setosa treated groups showed a reduced area of gastric lesion, with moderate disruption of the gastric epithelium as well as the mucosa stromal cell. The results obtained in this study suggest that the A. setosa possesses some anti-ulcerogenic properties, which may support evidence for its traditional use.
The antidiabetic and antioxidant properties of Athrixia phylicoides aqueous extract : an in vitro and ex vivo assessment
(Stellenbosch : University of Stellenbosch, 2011-03) Chellan, Nireshni; Muller, Christo John Frederick; Page, Benedict; De Beer, Dalene
ENGLISH ABSTRACT: Introduction: Athrixia phylicoides is an aromatic, indigenous shrub with high antioxidant content and numerous indigenous medicinal properties inferred by ingestion of an herbal brew of the plant. Commercialization of “bush tea” (derived from A. phylicoides) holds economic and developmental potential for indigenous communities provided the safety and efficacy of the herbal tea is established. Recently A. phylicoides has been shown by McGaw et al. (2007) to have similar antioxidant activity to Rooibos tea, and a unique, new flavonol (i.e. a polyphenolic antioxidant plant metabolite) 5-hydroxy-6,7,8,3′,4′,5′-hexamethoxyflavon-3-ol, unique to A. phylicoides, was isolated by Mashimbye et al. in 2006. With changes in the socio-economic climate and a new trend in merging Western lifestyle with traditional practices, new interest has been shown in herbal/natural remedies. Study Aim: The aim of this study was to firstly, determine the in vitro effect of A. phylicoides aqueous extract on glucose metabolism in cell lines that mimic the three key organs implicated in glucose homeostasis. Secondly, the study aimed to determine the potential ex vivo antioxidant and anti-inflammatory effect of the extract in pancreatic β-cells and peripheral mononuclear cells respectively. Methods: Leaves and fine twigs of A. phylicoides were processed into an aqueous extract. C2C12, Chang and 3T3-L1 cells were cultured under standard conditions and acutely exposed to increasing concentrations of extract and water vehicle, as well as 1 μM insulin and metformin as positive controls. Glucose uptake from 8 mM glucose culture media was determined using a fluorimetric oxidase method. Radioactive 14C-glucose oxidation to 14CO2 and determination of glycogen content of cells were used to assess the fate of intracellular glucose. RT-PCR was used to assess the extract effect on insulin-signalling gene expression. The antioxidative effect of A. phylicoides extract in pancreatic β-cells isolated from Wistar rats was determined by measuring nitric oxide (NO) production in response to hyperglycemic conditions. NO was labelled with diaminofluorocein diacetate and fluorescence was measured using flow cytometry. Insulin secretion of pancreatic β- cells was measured using radio-immuno assay. The anti-oxidative effect of the extract in lipopolysaccharide-stimulated peripheral mononuclear cells isolated from Wistar rats was determined by measuring the production of TNF-α using an ELISA kit. Results: C2C12 myocytes showed maximal increased glucose uptake at the 0.05 μg/μl extract concentration (228.3% ± 66.2, p<0.001). In Chang cells, A. phylicoides extract maximally increased the amount of glucose taken up at the 0.05 μg/μl concentration (134.5% ± 2.5, p<0.05). In 3T3-L1 cells, the extract maximally increased the amount of glucose taken up at the 0.025 μg/μl concentration (143.5% ± 10.3, p<0.001). An extract-induced increase in insulin receptor and glucose transporter four expression was seen in C2C12 myocytes. The oxidation of 14C-glucose to 14CO2 by C2C12 myocytes was maximally increased following acute exposure to the extract at 0.1 μg/μl (2919.3 fmol/1x10^6 cells ± 428, p<0.01). The oxidation of 14C-glucose to 14CO2 by Chang cells was maximally increased following acute exposure to extract at 0.1 μg/μl (4476.7 fmol/1x10^6 cells ± 1620, p<0.05); as seen in the C2C12 cells. A. phylicoides extract increased glycogen storage at all three concentrations tested in Chang cells, but maximally at the 0.025 μg/μl concentration (13.6 μg/1x10^6 cells ± 0.7, p<0.05). A. phylicoides extract did not have any measurable effect on the oxidative status of β-cells or the anti-inflammatory status of peripheral mononuclear cells. The extract did show an increase in first phase insulin secretion of β-cells in hyperglycemic conditions, although it was not significant. Conclusion: Athrixia phylicoides aqueous extract stimulates in vitro glucose uptake and metabolism in an insulin-mimetic manner, suggesting that this extract could potentially be beneficial to type two diabetics as an adjunct therapy.
Assessment of health status in a 20th century skeletal collection from the Western Cape
(2019-04) Alblas, Amanda; Friedling, Louise Jacqui; Greyling, Linda Magdalena; Stellenbosch University. Faculty of Medicine and Health Science. Dept. of Biomedical Sciences: Anatomy and Histology.
ENGLISH ABSTRACT: Studies on the health status of skeletal remains give insight into the standard of living and survival pattern of historic populations. Analysis of trauma and pathological conditions in human skeletal remains are important in biological anthropology, explaining patterns of malnutrition, stress, disease and trauma in a population. However, the difficulty to overcome is the fact that the majority of skeletal pathological conditions are limited in their interpretive significance, since they are nonspecific and a range of stressors can cause the lesions. By analysing multiple conditions within a known population, pathological responses for specific insults can be outlined and in return help in interpretation of the frequencies and distributions within and between populations. The Kirsten Skeletal Collection, housed at Stellenbosch University, Division of Clinical Anatomy broadly represents individuals from mainly low socio-economic communities of different population groups in the Western Cape, dating throughout the 20th century. The aim of this study was to macroscopically and radiologically examine adult individuals (n=624, nmales=438, nfemales=186) in this collection for skeletal markings that included malnutrition (diet and metabolic deficiencies), osteoarthritic lesions, neoplasms, infective diseases and antemortem trauma lesions to be used as baseline information in further anthropological studies on the people of the Western Cape region. Statistically, the prevalence of specific diseases or trauma were correlated between the sexes, three different age-at-death and population groups as well as three different time periods throughout the 20th century using two-way frequency-tests and correspondence analyses. During the 20th century, many factors resulted in poverty, and "non white” people, namely the South African Black (SAB) and South African Coloured (SAC) population groups, was especially disadvantaged by the laws introduced by the ruling political party. The influx of people from rural areas during World War II to work in the manufacturing industry resulted in the already overcrowded, unsanitary informal settlements around the Cape Peninsula to be flooded, influencing the disease patterns in the communities. The results demonstrated that the lowest prevalence of metabolic deficiencies, iron deficiency anaemia (porotic hyperostosis), growth arrest signs (Harris’ lines), infections such as tuberculosis, osteomyelitis and non-specific periosteal reactions were observed in the South African White (SAW) population group. This confirms that higher socio economic societies, that escaped the unsanitary conditions associated with poor housing and overcrowding environments, were more succesfully buffering themselves from malnutrition and exposure to pathogens. Better dental health as well as dental fillings were also more associated with the SAW population group that had unrestrained access to dentists and health care facilities. In contrast, the ‘non-white’ population groups, that were supressed during the Apartheids regime, demonstrated a high prevalence of malnutrition, metabolic deficiencies, tuberculosis and trauma lesions. The difference between the higher and lower social categories was especially recognised during the late time period when the Apartheid laws of population group segregation among others, started to show results in the 1960 and 1970. Later, during the 1980s and 1990s, political unrest caused by the supressed majority, and the world due to the Apartheid laws, resulted in sanctions and lower economic opportunities for South Africa. A notable higher frequency of infective markings on bone was observed during the late time period in the study, an indication of the successful use of antibiotics during the last decades of the 20th century, which provided more time for lesions to manifest on bones due to the increased life-span of people. Studies on skeletal collections rely on the assumption that the remains represent a past community, population group or populations from a specific region and can be used as a valid comparative reference for reconstructing different aspects of skeletal biology of past people that lived in that population. The Kirsten Skeletal Collection represents adult age groups between 18 and 100, three population groups, both sexes, various time periods over the 20th century as well as known cause of death and last known residence. However, this skeletal collection relies on body donations or retention of adult unclaimed or family donated bodies under the statues of the Inspector of Anatomy, and therefore, resulted in a biased sample. This bias is perceived in the fact that the Kirsten Skeletal Collection have an overrepresentation of males, aged individuals and people with lower socio-economic status. Although three major South African population groups are represented, suggesting depiction in population variation, it is highly unequal, especially representing the overpresented heterogenous mixed population group (SAC) that lived in and around the northern townships of Cape Town. Despite limitations, in general this study of the Kirsten Skeletal Collection may represent many of the traits in the population at that time and may be useful in future studies on honours, masters and PhD level to refine region- and population specific reference data and play a supportive role in research and training of specialists. These data to be collected and interpreted in future studies, include estimation of demographic parameters (age, sex, ancestry origin) as well as human variation, trauma biomechanics and pathological conditions. If the existing predispositions of the collection are acknowledged and accounted for by the use of suitable methodology, the Kirsten Skeletal Collection holds much potential to become a valuable resource for future research projects in osteology and related fields.
Beta secretase regulation and inflammation in pancreatic β-cells: the potential role of Rooibos
(Stellenbosch : Stellenbosch University, 2018-12) Burger, Joleen; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.; Chellan, Nireshni; Lopes, John; Muller, Christo J.F.
Introduction Chronic, low-grade inflammation is a hallmark of insulin resistance (IR) and underlies pancreatic β-cell failure and the development of type 2 diabetes (T2D), a disease characterized by a reduction in β-cell functional mass. However, therapeutics that directly protect β-cells from stressors, such as inflammation and oxidative stress, are limited. Amylin, a neuro-hormone, is co-secreted with insulin, therefore hyperinsulinemia often coincides with hyper secretion of amylin. Increased secretion of amylin is associated amyloid deposition which have detrimental effects on β-cell function. In pancreatic islets, β-secretase (BACE) modulates the deposition of cytotoxic islet amyloid, an initiator of intra-islet inflammation and oxidative stress, making BACE inhibition a therapeutic target. Insights into mechanisms involved in islet inflammation and the associated effect(s) of BACE, may reveal an opportunity to develop novel therapeutics to protect and preserve β-cells in T2D. In addition to their antidiabetic properties, aspalathin (Asp), Z-2-(β-D-glucopyranosyloxy)-3-phenylpropenoic acid (PPAG), and an unfermented Rooibos extract (GRT) may have anti-inflammatory effects in β-cells and may additionally modulate BACE activity. Aim To determine if GRT or two of its most bioactive polyphenols have BACE inhibition activity and can reduce pro-inflammatory effects in rat insulinoma (INS1) pancreatic β-cells. Methods A model of moderate inflammation was established in INS1 cells using a cytokine cocktail, containing tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interferon-γ (IFN-γ). Rat insulinoma cell viability, function, and oxidative stress was measured in response to the cytokine cocktail and exposure to Asp, PPAG, and GRT by quantifying cellular adenosine triphosphate (ATP) production, cell death via apoptosis and necrosis, proliferation rate, insulin/amylin secretion and content, reactive oxygen species (ROS) production and nitrate (NO2-) generation. Beta secretase inhibition profiling of GRT, Asp, and PPAG was assessed using fluorescence resonance energy transfer (FRET) in a purified enzyme assay, followed by kinetically assessing BACE activity in vitro. Results The cytokine cocktail induced a state of moderate inflammation after 24 hours, mainly through IL-1β. High concentrations of Asp (1000 μM) and moreso, GRT (1 mg/ml), showed a trend towards BACE inhibition compared to controls (56.20% ± 2.05, p<0.0001 and 39.80% ± 0.55, p<0.0001), but reduced mitochondrial dehydrogenase activity in inflamed INS1 cells (19.02% ± 2.98, p<0.0001; 36.88% ± 1.53, p<0.0001), while PPAG showed no measurable effect. Lower concentrations of Asp (0.1–10 μM), PPAG (0.1–10 μM), and GRT (0.0001-0.01 mg/ml) may have a protective effect on inflamed pancreatic β-cells as an increase, albeit not significant, in overall cell viability and function was observed, with a concomitant decrease in oxidative stress after 24 hours (97.66% ± 3.5, p<0.66; 95.54% ± 5.61, p<0.52; 96.80% ± 3.67, p<0.55).
Catecholamine release as mediator of intracellular enzyme activation in ischaemic perfused rat hearts
(Health and Medical Publishing Group (HMPG), 1975) Hough, F. S.; Gevers, W.
Isolated rat hearts perfused at suboptimal pressures have been studied as a model for generalized myocardial ischaemia. Glycogen phosphorylase a and hormone sensitive triglyceridase activities, measured as markers for endogenous catecholamine release, were significantly increased at low perfusion pressures. Pharmacological blockage of noradrenaline re uptake accentuated these effects, and depletion of catecholamine reserves eliminated them. This phenomenon may be important in the pathophysiology of cardiac ischaemia and its serious complications.
Cellular mechanisms involved in the recapitulation of endocrine development in the duct ligated pancreas
(Stellenbosch : University of Stellenbosch, 2011-03) Tchokonte-Nana, Venant; Page, Benedict; Du Toit, Don F.; University of Stellenbosch. Faculty of Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
ENGLISH ABSTRACT: Diabetes mellitus is amongst the leading causes of morbidity and mortality in the world, affecting young, adult and old people. Beta cell replacement therapy for insulin delivery remains the ultimate remedy for diabetes. However, insufficient donor pancreas and the use of immunosuppressive drugs prevent the wide-spread of this therapy. Other avenues of self generated beta cells within the organ itself need to be explored. Therefore, understanding the chronobiology of cellular mechanisms in the lineage of beta cell induced neogenesis is a valuable tool in improving beta cell replacement in patients with diabetes. The aim of this study was to induce recapitulation of the morpho-genetic sequence of endocrine cells development in the pancreas of rats after the pancreatic duct ligation (PDL) procedure. Serial sections of PDL tissues of the pancreas were obtained from 78 Sprague- Dawley rats and were assessed morphologically. The immunofluorescent tissues were statistically analysed using a computerized morphometry technique. The protein expression indices of Caspase3, Insulin, Pdx1, Ngn3, NeuroD and Pax6 were quantified. The efficiency levels of coexpression of these homeodomain proteins separately with insulin were defined by the ratio of the mean value of insulin expression to the mean value of their respective protein expression. The morphological changes were characterized by the appearance of granulated acinar cells at 6 hours post-PDL and the proliferation of endocrine tissues from 84 hours through to 120 hours. The morpho-immunofluorescent evaluation showed the highest immunoreactivity of Caspase3 and Pdx1 at 6 hours, Ngn3 at 36 hours, Pax6 and insulin at 84 hours while NeuroD expression was at 120 hours. The immunohistofluorescent analysis showed that caspase3 and Pdx1 were the first to be expressed at 6 hours while the insulin and NeuroD expression appeared later at 84 hours and 120 hours, respectively. However, Pax6 expression was continuous across time periods post-PDL, while Ngn3 expression showed a peak at 36 hours. The efficiency (highest and earliest expression) of co-expression of all these homeodomain proteins with insulin was restricted between 12 hours and 24 hours. The optimal efficiency was at 12 hours by Ngn3 with insulin. A good efficiency was shown for Pdx1 with insulin, NeuroD with insulin and Pax6 with insulin at 12 hours and 24 hours, respectively. A low efficiency was observed for insulin and caspase3 co-expression at 24 hours. This study suggests that for transplantation, PDL tissues harvested at an early time post-PDL (between 12 and 24 hours) could yield a higher success rate; the study also provides evidence for a connection between morphological changes in the PDL pancreas and the protein synthesis necessary for the lineage of endocrine cell development.
The characterisation of candida isolates from the oral cavities of a group of acute leukemia patients
(Stellenbosch : Stellenbosch University, 1997-12) Paul, Lynthia Vivienne; Hauman, C. H. J.; Warren, R.; Van Wyk, C. W.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences : Anatomy and Histology
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die invloed van chemoterapie en antifungale terapie op Candida spesies in die mondholte van 29 leukemie pasiënte te ondersoek. Smere en mondspoele was geneem van die pasiënte. Candida isolate was op Sabouraud dekstrose agar sowel as differensiële media gekweek. Isolate was geïdentifiseer met behulp van fenotipiese eienskappe asook koolhidraat assimilasie profiele. Genotipering van C. albicans stamme was gedoen met behulp van die C. albicans spesie-spesifieke peiler, Ca3.
Clinical implications of the variations of sciatic nerve bifurcation on the popliteal nerve block
(Stellenbosch : Stellenbosch University, 2018-12) Mady-Goma, Chancy Rosine; Tchokonte-Nana, Venant; Stellenbosch University. Faculty of Health and Medical Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
ENGLISH ABSTRACT: The sciatic nerve (SN) is a major nerve of the lower limb, innervating the posterior thigh, the hip and knee as well as structures below the knee through its branches. The SN division occurs in the popliteal fossa (PF) at the level of the knee. However, various studies report great variations in the level of division of the SN, ranging between 3.3 and 65.1%. These variations were suggested as a possible cause in failures of the popliteal block (PB). Therefore, the aim of this study is to describe the level of division of the SN in a South African cohort and to evaluate the success rate of three approaches to the PB. Following the simulation of the PB in 22 lower limb specimens, the popliteal fossae of 61 cadavers were dissected and the sciatic nerve properly exposed. The level of division was described and the location and distance between the dye and the nerve measured. Variations represented only 11.48% of cases, similar to textbooks’ description (12%). The bifurcation pattern of the SN in this South African cohort was therefore comparable to the standard one. The distance between the SN and the PC varied between 20 mm and 405 mm, with a median of 55 mm, close to 60 – 70 mm found in most studies. The prevalence of variations was higher in females (ratio F:M=2.78) and 55.56% were bilateral. With the SN dividing in the PF, the simulation predicted a 100% success rate with no difference between the approaches used. Nevertheless, a higher division of the SN would compromise the success of the block. Overall, the SN division in our study population follows the normal pattern with a lesser degree of variations (11.48%). The division of the nerve in the PF might ensure a successful block in 95 to 100% of cases, in contrast to cases of high variations. Nevertheless, a preoperative imagery is strongly recommended, especially in women for early identification of variations to avoid failures of the PB, irrespective of the approach used.
The comparative functional anatomy of the forelimb in two african mole-rat species, bathyergus suillus and heterocephalus glaber.
(Stellenbosch : Stellenbosch University, 2021-12) Doubell, Narusa Suria; Kotzé, Sanet H.; Sahd, Lauren; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology. Division of Clinical Anatomy.
ENGLISH ABSTRACT: Different digging and communication methods are observed in various subterranean mole-rat species. Seismic signalling in the form of hind foot-drumming is the main communication method in most solitary mole-rat species, such as the scratch-digging Bathyergus suillus. The aim of the present study was to determine if hind foot-drumming and scratch-digging influence the morphology of the fore limb muscles in a drumming, scratch-digging species, B. suillus, belonging to the family Bathyergidae and a non-drumming, chisel-tooth digging species, Heterocephalus glaber belonging to the family Heterocephalidae. Furthermore, the secondary aim was to determine if somatosensory mechanisms that may be responsible for the detection of seismic signals could be identified histologically in the foot pads and lateral aspect of the feet in both species. Four muscle architecture parameters were measured and compared in 40 formalin-fixed muscles from the right forelimb of each species (n=6). The composition of type I and II fibres as well as the glycolytic, oxidative glycolytic and oxidative fibres in 21 forelimb muscles were histochemically and immunohistochemically determined in six fresh B. suillus and six fixed H. glaber specimens. The densities of Pacinian corpuscles, Merkel cells, Ruffini corpuscles and Meissner corpuscles were determined within the footpads and the morphology of the robust hairs on the lateral aspect of the feet was described. Muscles involved in the power stroke of digging had higher muscle mass percentage, force output and shortening capacity in B. suillus compared to H. glaber. Significantly higher percentages of glycolytic fibres were observed in the scapular elevators and digital flexors of B. suillus. These results suggest that the forelimb muscles involved in digging in B. suillus provide fast and powerful motions for effective burrowing. The m. sternohyoideus had significantly more oxidative fibres in H. glaber compared to B. suillus. Furthermore, the m. sternocleidomastoideus in H. glaber had significantly higher physiological cross-sectional area (PCSA) and fascicle length values compared to B. suillus. Regionalisation of type I and II fibres was observed in the m. claviculo-scapularis of B. suillus and m. triceps brachii caput medialis in H. glaber. Significantly higher densities of Meissner corpuscles in the drumming B. suillus suggests that this somatosensory mechanism in their footpads may be responsible for detecting seismic signals. The hairs on the lateral aspect of the feet did not have the typical follicle-sinus complex seen in sensory hairs. However, Merkel cells within the outer root sheath and the nervous tissue surrounding the hairs in both species are indicative of functioning either as tactile perception for movement in burrows or moving loosened soil around within the burrows. Stellenbosch University https://scholar.sun.ac.za iv In conclusion, the differences in the muscle architecture and muscle fibre typing between the two species may reflect adaptations for scratch-digging and production of seismic signals in B. suillus. Additionally, the muscle architecture and fibre type compositions in the neck muscles of H. glaber may point toward faster contractions for chisel-tooth digging. However, the phylogeny of the two species may also be responsible for these differences and not just behavioural demands such as hind foot-drumming and digging methods.
Composition of the Kirsten skeletal collection at Stellenbosch University
(Academy of Science of South Africa, 2018) Alblas, Amanda; Greyling, Linda M.; Geldenhuys, Elsje-Marie
The Kirsten Skeletal Collection is curated in the Division of Anatomy and Histology, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa. It comprises the largest documented cadaver-derived South African coloured skeletal collection in the world. Our aim in this paper is to present an inventory and characterise the identified skeletons in the Kirsten Skeletal Collection as well as provide a descriptive indication of what researchers can expect to encounter at the anthropology unit at Stellenbosch University. The skeletal material was derived mainly from the cadaver donation programme of the Division of Anatomy and Histology over a 58-year period (1957–2015). All pertinent information for each individual skeleton is entered into a database and a full skeletal inventory is established. The skeletal database registry was analysed to demonstrate the distribution of age, sex and population affinity of individuals in the collection. Currently, this collection consists of 1161 skeletons with known records. Despite differences in the age and sex composition, the skeletal profile in general reflects mainly the profile of the Western Cape population. Most individuals were born between 1920 and 1950, placing the Kirsten Skeletal Collection in the early to mid-20th century. The age at death for the greatest proportion (41.8%) of individuals was between 40 and 60 years. Current biological profile techniques in age, ancestry and sex estimation can be improved and, among others, new regional and ancestral specific standards for the biologically unique and diverse South African coloured population can be developed.
Congenital anomalies in the vertebral column associated with thoracolumbar transitional vertebrae
(Stellenbosch : Stellenbosch University, 2017-11-08) Du Plessis, Anneli Merle; Greyling, Linda Magdalena; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Division Anatomy and Histology.
ENGLISH ABSTRACT : According to Byrd & Comiskey (2016), disrupted ossification during development results in abnormal skeletal development. A study conducted on congenital anomalies by Masnicová & Beňuš (2003), stipulated that most skeletal congenital defects are located in the vertebral column. The most common skeletal defects of the vertebral column are neural tube defects (NTD’s), spondylolysis and cranial-caudal border shifts (Masnicová & Beňuš 2003). In reviewed literature, case studies have reported various congenital defects that are simultaneously present within the vertebral column of an individual. There is, however, a lack of evidence to substantiate whether the mutually inclusive observations resulted by chance, or whether an association between the defects is present. The aim of this study was to determine whether associations exist among random congenital defects in the vertebral column. The objective of this study was to identify and determine the frequency of random congenital defects from a subset of defects in the vertebral column. A selection of skeletal remains were taken (n=35) from a subset in the Kirsten Skeletal Collection at Stellenbosch University. The subset comprised specimens from the population (N=±1100) with congenital defects in the vertebral column that has a reviewed prevalence of 0.5/1000 worldwide. This study hypothesised that there is an association between random congenital defects that results from border shifts or disrupted neural arch formation. The congenital defects considered in the study included: lumbosacral transitional vertebrae (LSTV), thoracolumbar transitional vertebrae (TLTV), spondylolysis, NTD’s and sacro-coccygeal fusion. Descriptive analysis was performed to determine the frequencies of defects in the selection. The descriptive analyses are illustrated in frequency distribution tables for each type of defect evaluated in the study. This study found that every specimen in the selection had TLTV and one or more additional random congenital defect in the vertebral column. Based on the finding, it can be claimed that an association exists between TLTV and other congenital defects of the vertebral column. TLTV were identified based on intermediary characteristics between the thoracic and lumbar regions present in the vertebra. This study concludes that when TLTV is present, it will be associated with one or more random defect in the vertebral column discussed in this study. The association between TLTV and other congenital defects provides an indirect association between all cases where various congenital defects are simultaneously present.
Congenital Anomalies of the Tracheobronchial Tree: A Meta-Analysis and Clinical Considerations
(2020-11) Wong, Linda M; Cheruiyot, Isaac; Santos de Oliveira, Maria Helena
Background 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.
The correlation between cranial and post-cranial skeletal elements for resolving and reconstruction of comingled skeletal remains in victim identification
(Stellenbosch : Stellenbosch University, 2019-04) Marais, Johan Christian; Alblas, Amanda; Greyling, L. M.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences: Anatomy and Histology.
ENGLISH ABSTRACT: Upon discovery of comingled disarticulated skeletons, actual matching of different skeletal elements to a particular individual can be extremely difficult. Available literature regarding the matching of skeletal elements, show few studies correlating skull measurements with post-cranial elements, with the majority of cases determining correlations with stature. The aim of this study is to assess the degree of correlation between cranial and post-cranial skeletal elements, of the three dominant South African population groups, by means of direct correlations of measurements. Skeletons of individuals (N=296) of both males (n=148) and females (n=148) of South African black (n=100), South African white (n=97) and South African coloured (n=99) population groups, were assessed in three distinct manners. Firstly, three correlation sets were recorded: 21 cephalometric elements were correlated with eight long-bone measurements, and six occipital condyle measurements with morphologically mirrored measurements on the superior articular facet of the first cervical vertebra were correlated. The last of the correlation sets consisted of the lengths and breadths of the neural foramina from foramen magnum up to C2. Secondly, Principal Component Analyses were conducted on the 21 cephalometric elements, the eight long-bones measurements, the 12 articular facet measurements, and the six neural canal measurements. Lastly, t-tests were conducted to determine if any of the measurements were sexually different. From these assessments, a connection between some of the cephalometric elements and the long bones were observed. Most notably, the novel construct known as representative facial height (NLH.MRH), which is the summation of the nasal height and the maximum ramus height of the mandible for all three population groups. The South African white males, however, showed a much weaker connection with NLH.MRH, though, the basion-bregma height correlated well with the long bones. It was determined that the length measurements outperformed the breadth measurements in terms of correlative strength for the three population groups, in the atlanto-occipital joint. A direct relationship was established within the neural canal from foramen magnum up until C2 for all three population groups. A clear platform is created for future research into constructing regression formulae for matching skulls with long bones. The articular facet and neural canal results can be used in a combined assessment for matching a skull with a body that has an intact cervical spine, by developing a regression model from a grouping of both measurement sets. These regression models may then be implemented in the sorting of comingled remains in situations such as mass graves and mass disasters.
Defining a method to predict mouth morphology in edentulous skulls
(Stellenbosch : Stellenbosch University, 2022-04) Daniels, Luke-John; Alblas, Amanda; Smith, Kathryn; Roberts, Tina; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences: Anatomy and Histology.
ENGLISH ABSTRACT: Forensic facial depiction (FFD) is the process whereby a face is modelled to depict a face from an unknown deceased individual’s skull to assist with human identification. The field of FFD that has not been researched extensively, is the edentulous mouth, where edentulism refers to the condition of not having teeth. Therefore, this study attempted to establish whether a method could be produced to predict edentulous mouth morphology for FFD practice. To achieve this, Pearson’s correlation analysis was used and the relationship between the individual’s soft tissue measurements (somatometry) and skull measurements (osteometry) were analysed. Dentate patients, those with teeth, were also included in the study to understand the morphometric difference between the mouths of dentate and edentulous patients. Cone Beam Computer Tomography (CBCT) scans of n=63 patients were retrieved. This included 40 dentate patients (n=24 males and n=16 females) and 23 edentulous patients (n=7 males and n=16 females). The patients’ CBCT scans were retrieved from the Oral Health Centre of the University of the Western Cape’s Picture Archiving and Communication System. The morphometrics software, Stratovan CheckpointTM, was used to perform osteometry and somatometry on these scans. The somatometry of all patients included measuring soft tissue thicknesses (STTs) of the upper mouth as well as the patients’ lip height (LH) and philtrum length (PL). For the edentulous patients, the STTs included the mid-philtrum (H), and mid- upper lip margin (I). For the dentate patients, the STTs measured were the H, I, the upper incisor (II) and lateral supra-labiale (F). For osteometry, all patients’ skulls were measured to retrieve the following skull lengths: the bizygomatic breadth, basion-prosthion length, basion- gnathion length, maxillo-alveolar breadth, maxillo-alveolar length, nasion-prosthion, and the cranial base length. These lengths were then used to calculate the maxilla-alveolar (MAI), upper facial, subnasal gnathic (SGI), and gnathic indices. A Shapiro-Wilk test was performed, and it was found that all osteometry and somatometry were normally distributed. Therefore, the correlation analysis could be applied. For the edentulous patients, the correlation analysis was only applied to the female patients since the male group was below the suggested sample size for correlation analysis (n<10). The results found that no significant correlations exist between female edentulous mouth somatometry and osteometry. For the dentate males, significant correlations were identified in: the MAI, and II- right and II-left; GI and H; and SGI and LH. For the dentate females: SGI, and II-left, F-left, and LH. Based on this study, it cannot be concluded that osteometry is a good predictor of edentulous mouth morphology. Other factors may play a role in the results of this research such as the sample size and certain edentulous anomalies, for example, residual ridge resorption (RRR). In the dentate group, significant correlations were found since RRR did not affect these patients. Therefore, for future studies, it is suggested that a larger sample is retrieved that is strictly controlled for edentulous anomalies.
Description of the cerebral vasculature in a southern African cadaver cohort
(Stellenbosch : Stellenbosch University, 2016-03) Cilliers, Karen; Page, Benedict; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences. Anatomy and Histology.
ENGLISH ABSTRACT: Few studies give a complete description on the origin, absence, duplication and triplication of the cerebral cortical branches. The anterior cerebral artery (ACA) varies considerably and this complicates the description of the normal anatomy. The most commonly discussed branching types of the middle cerebral artery (MCA) include bifurcation and trifurcation. Branching of the posterior cerebral artery (PCA) has not been adequately described; only the division level of the parieto-occipital (PoA) and calcarine arteries has been discussed. Anomalies of the cerebral arteries have been reported. To the author’s best knowledge, no previous studies have investigated the anatomy of the cerebral arteries in a Western Cape population. Therefore, the aim of this study is to describe the anatomy and anomalies of the cerebral vasculature in a Southern African cadaver cohort. Twenty hemispheres were used for the pilot study and 126 hemispheres for the present study. These 126 hemispheres consisted of 88 males and 38 females, between the ages of 22 and 84. Specimens were distributed over three population groups, namely, coloured (n=76), black (n=38), white (n=10) and unknown (n=2). The arteries were injected with coloured silicone. The external diameter and length of all the cortical branches of the cerebral arteries were measured using a digital micrometre. The diameter and lengths indicated statistically significant differences on the right and left side, between males and females, different population groups and different age groups. The most commonly absent artery was the callosomarginal artery, and the most commonly duplicated artery was the paracentral lobule artery. The origin of the cortical branches was similar to the descriptions in the literature; however, the common trunks and unusual origins were also noted. The branching pattern of the MCA was classified according to the 11 different subtypes described in the literature. Medial bifurcation was most commonly observed. The branching pattern of the PCA was assessed, and in most cases there was additional branching before the division of the calcarine artery and PoA. Anomalies observed in the present study included bihemispheric ACA (19.8%), median ACA (11.6%) and fenestration of the PCA (1.6%). The only anomaly observed in the pilot study was fenestration of the PCA (5.0%). A shorter trunk may play a role in aneurysm formation, and changes in vessel diameter could indicate early signs of several pathological conditions. Aneurysms can be observed at the branching of cerebral vessels, highlighting the importance of a thorough knowledge of the vascular anatomy. The MCA branching subtypes were described, since only bifurcation and trifurcation are usually noted. Furthermore, the branching pattern of the PCA has not been adequately described in previous reports; therefore the possible branching types were defined. Anomalies of the cerebral arteries are usually only mentioned; therefore the bihemispheric and median ACA were fully described (origin, length, diameter and area supplied). Given the important implications that the anatomical variation of the cerebral arteries

Browse

Browsing Anatomy and Histology by Title

Results Per Page

Sort Options