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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Clinical appropriateness of referrals to the echocardiography clinic at the Chris Hani Baragwanath academic hospital

Dube, Farai January 2017 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg in partial fulfillment of the requirements for the degree of Master of Public Health. Johannesburg, 2017 / Background South Africa is grappling with a quadruple burden of disease, and cardiovascular diseases with other non-communicable diseases are on the increase. Echocardiography is an expensive but vital basic screening and diagnostic tool for cardiac patients. Appropriate use criteria (AUC) have been developed for echocardiography to assist with avoiding unnecessary echocardiograms. Aim and Objectives of the study The aim of the study was to determine the clinical appropriateness of referrals to the echocardiography clinic at Chris Hani Baragwanath Academic Hospital using AUC. The specific objectives were: 1. Describe the socio-demographic profile of patients referred for echocardiography 2. Determine the clinical appropriateness of echocardiography referrals 3. Describe the clinical profile of patients referred for echocardiography 4. Determine whether socio-demographic and clinical profile influence the appropriateness of echocardiography referral Methods During July 2015, a cross-sectional study was conducted among all new patients referred to the echocardiography clinic at the Chris Hani Baragwanath Academic Hospital (CHBAH). Following informed consent, patient demographic information was collected. Clinical and echocardiography reports were obtained for all new patients and analyzed, using the 2011 AUC criteria for echocardiography. The data were analysed using Minitab version 16. Results The majority of the study participants (n=270) were black African (88.3%); they had a mean age of 53 years (SD ±16.6) and 63.1% were female. The study found that 93.3% of new patients were appropriately referred, 3.7% (n=10) were inappropriately referred and 3.0% (n=8) had uncertain indications for echocardiography. Hypertension 45.5% (n=123/270) was the most common clinical diagnosis on echocardiogram request, with the post-echocardiogram evaluation confirming that 41.6% (111/267) of all the patients had hypertensive heart disease. An HIV positive status was documented in only 10.6% (n=29) of the patients. Conclusion The AUC is a useful tool and yielded similar results at the CHBAH. There is a high burden of hypertensive heart disease in this population, which requires specific prevention strategies. / MT2017
2

Compression and segmentation of three-dimensional echocardiography

Hang, Xiyi. January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvii, 151 p.; also includes graphics (some col.). Includes bibliographical references (p. 145-151). Available online via OhioLINK's ETD Center
3

Interaction of ultrasonic waves and tissues modeling, simulations, and applications /

D'Hooge, Jan. January 1900 (has links)
Thesis (Ph. D.)--Katholieke Universiteit te Leuven, 1999. / Includes bibliographical references (p. 227-240).
4

Interaction of ultrasonic waves and tissues modeling, simulations, and applications /

D'Hooge, Jan. January 1900 (has links)
Thesis (Ph. D.)--Katholieke Universiteit te Leuven, 1999. / Includes bibliographical references (p. 227-240).
5

The utilisation of ultrasonic tissue characterisation for the evaluation of myocardial status in patients with acute myocardial infarction

Hancock, Jane January 2003 (has links)
No description available.
6

The impact of exercise duration, exercise intensity, fitness and environmental conditions on the development of exercise induced cardiac fatigue

Dawson, Ellen Adele January 2003 (has links)
No description available.
7

Reproducibility and interpretation in tissue Doppler echocardiography

Storaa, Camilla January 2004 (has links)
As cardiovascular disease is the single most common cause ofdeath in the western world, and since there is a closeconnection between cardiovascular disease and left ventricular(LV) function, good methods for the assessment of LV functionis highly needed. A widely used tool for the diagnosis of LVdisease is echocardiography, a technique which today faces twodi_culties; the low reproducibility and the subjectiveinterpretation. The present dissertation aims to quantifyreproducibility, to study the factors that influencereproducibility and to provide tools for simplifying theinterpretation of tissue velocities measured by Dopplerultrasound. The reproducibility has been studied by letting twoindependent observers measure tissue Doppler velocities toinvestigate how well their measurements agree. To improvereproducibility an algorithm for the automatic detection ofpre-defined echocardiographic localizations is presented. Oneof the most difficult skills for the sonographer to master,thus leading to reduced reproducibility, is the transducermanipulation. The effect of poor transducer manipulation hasbeen modeled, and we show that even a poorly placed transducermay yield images which are easily mistaken for good, however,when scanning in two orthogonal planes the transducermisplacement is easily detected. Interpretation of the echocardiograms is influenced byseveral parameters. As the tissue velocities are measured byutilizing the Doppler effect, only the velocity componentdirected towards the transducer can be measured, thus thealignment of the heart within the view of the transduceraffects the tissue velocity measurements. The effect of thishas been investigated, and it is demonstrated that since themyocardium primarily has longitudinal motion and thus thevelocity vectors are mainly longitudinal, imaging in the apicalview will give little error in the velocity measurements. Filtering of the tissue velocity signals have becomecommercially available with the hope that it will improvereproducibility and simplify interpretation. One set of lowpass filters has been tested, and it is seen that there is arisk of overdoing the filtering and cause an underestimation oftissue velocity parameters. A similar effect to low passfiltering is seen when using too low sample rate when recordingthe tissue velocities. Finally a new imaging modality, tissue motion imaging, ispresented, where myocardial displacement, velocity, strain andacceleration may be interpreted from one single image, insteadof the situation today where several measurements must beperformed to get an overview of all these parameters. The thesis concludes that reproducibility can be improved bycurve smoothing and that interpretation can be simplified usingadvanced methods of parametric imaging.
8

Reproducibility and interpretation in tissue Doppler echocardiography

Storaa, Camilla January 2004 (has links)
<p>As cardiovascular disease is the single most common cause ofdeath in the western world, and since there is a closeconnection between cardiovascular disease and left ventricular(LV) function, good methods for the assessment of LV functionis highly needed. A widely used tool for the diagnosis of LVdisease is echocardiography, a technique which today faces twodi_culties; the low reproducibility and the subjectiveinterpretation. The present dissertation aims to quantifyreproducibility, to study the factors that influencereproducibility and to provide tools for simplifying theinterpretation of tissue velocities measured by Dopplerultrasound.</p><p>The reproducibility has been studied by letting twoindependent observers measure tissue Doppler velocities toinvestigate how well their measurements agree. To improvereproducibility an algorithm for the automatic detection ofpre-defined echocardiographic localizations is presented. Oneof the most difficult skills for the sonographer to master,thus leading to reduced reproducibility, is the transducermanipulation. The effect of poor transducer manipulation hasbeen modeled, and we show that even a poorly placed transducermay yield images which are easily mistaken for good, however,when scanning in two orthogonal planes the transducermisplacement is easily detected.</p><p>Interpretation of the echocardiograms is influenced byseveral parameters. As the tissue velocities are measured byutilizing the Doppler effect, only the velocity componentdirected towards the transducer can be measured, thus thealignment of the heart within the view of the transduceraffects the tissue velocity measurements. The effect of thishas been investigated, and it is demonstrated that since themyocardium primarily has longitudinal motion and thus thevelocity vectors are mainly longitudinal, imaging in the apicalview will give little error in the velocity measurements.</p><p>Filtering of the tissue velocity signals have becomecommercially available with the hope that it will improvereproducibility and simplify interpretation. One set of lowpass filters has been tested, and it is seen that there is arisk of overdoing the filtering and cause an underestimation oftissue velocity parameters. A similar effect to low passfiltering is seen when using too low sample rate when recordingthe tissue velocities.</p><p>Finally a new imaging modality, tissue motion imaging, ispresented, where myocardial displacement, velocity, strain andacceleration may be interpreted from one single image, insteadof the situation today where several measurements must beperformed to get an overview of all these parameters.</p><p>The thesis concludes that reproducibility can be improved bycurve smoothing and that interpretation can be simplified usingadvanced methods of parametric imaging.</p>
9

Real time three dimensional echocardiographic assessment on patients with beta-thalassaemia major

Fong, Nai-chung. January 2001 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 62-65).
10

Real time three dimensional echocardiographic assessment on patients with beta-thalassaemia major

方乃聰, Fong, Nai-chung. January 2001 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

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