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Clinicians frequently study arterial Doppler velocimetric waveforms depicted by Doppler sonography of the kidneys, the heart, the brain, and the feto-maternal circulation to assess the well-being of the aforementioned vital organs. The waveform interpretation of the Doppler indices can be studied using a mathematical model. The developed models serve as teaching tools and for easy comprehension of the regulatory mechanism of the organs. It will also obtain accurate wall shear stress (WSS) and likely atherosclerotic sites can be predicted early. The aim of this review is to reveal the imperatives of mathematical models in the study of the physical interpretation of Doppler velocimetry. The models will explore sonographic Doppler velocimetry and computational fluid dynamics (CFD) in determining the segments of the arteries that are prone to the development of atheromatous plaque. It will be achieved by comparing and computing the measurement differences of the WSS. A thorough literature review was carried out between 1971 and 2021 on the mathematical modeling of blood dynamics and Doppler velocimetry of different blood vessels, across various electronic databases including NC AHEC Digital Library, PUBMED, ERIC, MEDLINE, Free Medical Journals, and EMBASE. The results of the literature search were presented using the PRISMA flow chat. The narrative review of the mathematical models of arterial blood dynamics is based on incompressible Navier-Stokes equations, the Windkessel model, and CFD. It was deduced that the blood flow velocity decreased with time across the varying frequency from 0.2Hz to 0.50Hz in the interlobar arterial channels. The review also revealed that adult humans' Doppler indices of the renal-interlobar artery agree with developed models of renal interlobar arterial blood dynamics. The mathematical model measurements of the great vessels matched the sonographic Doppler velocimetry with <15% variation. In our fast-paced world of epidemiological transition, the imperatives of mathematical modeling of arterial flow dynamics based on the Navier-Stokes equations to represent various physiologic and pathologic situations cannot be overstated. The practical consequences include the possibility of mathematical models to acquire precise WSS distribution and early detection of potential atherosclerotic sites during cardiovascular Doppler sonography.
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Sonography has proven to be valuable diagnostic imaging equipment in the work-up of patients infected with acquired immune deficiency syndrome (AIDS) and tuberculosis (TB) coinfection. An extensive literature search was conducted between 1994 and 2021 for original peer-reviewed articles in the English language on ultrasound application in the diagnosis of extrapulmonary TB (EPTB), ultrasound application in infectious diseases in resource-constrained settings, point-of-care ultrasound in resource-scarce settings among others, across various electronic databases including MEDLINE, PubMed, POPLINE, Scopus and Google Scholar, among others and some gray literature were also retrieved. Emerging themes were identified by their recurrence in literature. Ultrasound imaging is a rapid diagnostic tool and can accurately identify and characterize pathologic findings in patients infected with HIV/AIDS and TB co-infection, such as enlarged lymph nodes, pericarditis, and pleural effusion, among others for prompt patient management. Ultrasonography is cheaper and portable; interfacing software has become more users friendly and image quality significantly improved, making it possible for the provision of imaging services in an increasing number of clinical settings in resource-limited settings where access to diagnostic imaging is scarce. The use of focused assessment with sonography for HIV (FASH) for prompt diagnosis of EPTB in regions with a high incidence of HIV/AIDS and TB co-infection will aid in prompt diagnosis and treatment of patients with undifferentiated TB, thus impacting on morbidity and mortality. The training and deployment of sonographers in endemic regions with a high prevalence of HIV/AIDS and TB co-infection, to diagnose EPTB using FASH protocol is a viable option that is in line with the global drive for intensified case finding and treatment algorithm, with a view to meeting the sustainable development goals target of ending HIV and TB epidemics and achieving universal health coverage.
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INTRODUCTION: Chronic liver disease is a public health burden worldwide. Portal hypertension is a major portosystemic abnormality in chronic liver disease. This study aimed to determine the main, right, and the left portal vein diameter in patients with chronic liver disease. MATERIALS AND METHODS: A cross-sectional study was carried out at the Abubakar Tafawa Balewa University Teaching Hospital, Bauchi, northeastern Nigeria from December 2018 to September 2019. Ethical clearance was obtained from the institutional review board. A total of 200 subjects were recruited comprising 100 patients with chronic liver disease and 100 age-matched controls, aged 18 years and above. A transabdominal ultrasound scan was carried out measuring the main, right, and left portal vein diameter while lying supine and/or in the right anterior oblique position after overnight fasting, or 6 hours before the scan. Data analysis was done using SPSS version 22.0. Descriptive statistics (mean, standard deviation) and Pearson's correlation were used. RESULTS: There were 106(53%) males and 94(47%) females, aged between 18 and 73 years with a mean age of 46.79 ± 15.43. The main, right, and left portal vein diameter in patients with chronic liver disease was 14.51 ± 0.78 mm, 6.83 ± 0.81 mm, and 6.26 ± 0.74 mm, which were higher than those of their control. The portal vein diameter positively correlated (weak) with age and respiratory phases among participants (P < 0.05). CONCLUSION: This study found the main, right, and left portal vein diameter among patients with chronic liver disease to be larger than those of the controls. Ultrasonography is a reliable diagnostic tool in evaluating portosystemic pathologies.
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BACKGROUND: Sonographic evaluation of abdominal organs is an important work up in managing sickle cell disease (SCD) patients. This study aimed at evaluating abdominal organs by sonography among SCD patients. METHODOLOGY: A cross-sectional study was carried out in Maiduguri, Nigeria from April 2014 to July 2015. Two hundred and fifty-two patients participated in the study, with 126 controls and 126 SCD patients. There were 131 (52%) males, and 121 (48%) females, with age range 3-38 years. Measurements were done using ultrasound machine with probe frequencies ranging from 1-4MHz and 4-9MHz in supine, right and left oblique positions for optimum visualization of the abdominal organs. RESULTS: Participants within the age range of 10-15 years had the highest frequency with 88 (34.9%), followed by those within the age group of 17-23 years with 86 (34.1%), and the least were those within the age group of 30 years and above with 8 (3.2%). Hepatomegaly was found in 53 (75.7%), and increased echogenicity of the liver was found in 50 (94.3%) of the SCD patients, P = 0.000. Gallstones were found in 45 (17.9%), gallbladder sludge was found in 51 (21.4%) and thickened gallbladder wall was found in 84 (33.3%) of the SCD patients, P = 0.000. Autosplenectomy was found in 45 (17.9%), splenomegaly in 63 (24.9%), and calcified spleen in 18 (8.7%) of the SCD patients, P = 0.000. Enlarged kidneys in SCD patients were found in 61 (98.4%) and 63 (98.4%) on the right and left kidneys, respectively. Shrunken kidneys were found in 5 (2.0%) and 4 (1.6%) of the SCD patients on the right and left kidneys, respectively, P = 0.000. CONCLUSION: Abdominal sonography in SCD patients revealed varied remarkable changes in the size, echotexture, intraluminal deposits and wall thickness in the liver, gallbladder, kidneys, and spleen.
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BACKGROUND: Accuracy of some ultrasound equations used in our locality for fetal weight estimation is doubtful. OBJECTIVE: To assess the accuracy of common ultrasound equations used for fetal weight estimation. SUBJECTS AND METHODS: A longitudinal study was conducted on selected Nigerian obstetric population at Central Hospital, Kwale between March, 2009 and January, 2011. Sonography was performed on 412 women with advanced singleton cyesis and measurements of BPD, HC, AC, and FL were obtained and figured into 12 common ultrasound equations for the estimation of fetal weight. The actual birth weight at delivery was recorded. RESULTS: The highest intraclass correlation coefficient was generated by the Hadlock 5 and Hsieh 2 equations. The least mean absolute percent error was obtained with Hsieh 2 equation, followed by Woo 3, and Hadlock 5. These equations also had the least percentage error and the least range of limits of agreement in the same order with no significant difference between their mean fetal weight estimates and that of the actual birth weight (p > 0.05). All twelve equations had strong positive correlation with the actual birth weight with Nzeh 2 equation the least. CONCLUSION: Hsieh 2 equation has the best accuracy in fetal weight estimation studied.