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dc.contributor.authorLange, Aleksandraen
dc.date.accessioned2018-01-31T11:22:17Z
dc.date.available2018-01-31T11:22:17Z
dc.date.issued1999en
dc.identifier.urihttp://hdl.handle.net/1842/26677
dc.description.abstracten
dc.description.abstractAlthough conventional two-dimensional and Doppler blood-flow echocardiography are the standard imaging approaches in the assessment of heart disease they do not provide anatomic reconstructions in a form that resembles the cardiac morphology as visualized by the surgeon.en
dc.description.abstractThe work presented in this thesis has explored the hypotheses that threedimensional echocardiography facilitates spatial recognition of intracardiac structures and therefore enhances the diagnostic confidence of echocardiography in congenital and acquired heart disease. The accuracy of three-dimensional reconstructions has been validated in vitro using two different phantoms and in vivo comparing the results with other established diagnostic techniques or surgical findings. Additionally, as the main limitation of transthoracic three-dimensional echocardiography is poor image quality in a substantial proportion of adult patients, Doppler myocardial imaging has been tested as a potentially superior method to conventional grey-scale imaging for transthoracic three-dimensional image acquisition.en
dc.description.abstractIn vitro, using a virtual computer-generated phantom and a dynamic tissuemimicking phantom, the accuracy of both linear measurements and volume computation obtained from three-dimensional images was established. For both grey-scale and Doppler myocardial imaging, a detail of 1.0 mm dimension and two details separated from each other by a distance of 1.0 mm were the smallest structures and distances identified from a three-dimensional image. When testing the accuracy of volume measurements it appeared that both techniques marginally underestimated the true phantom volume (by approximately 1.0 ml for Doppler myocardial imaging and 4.0 ml for grey-scale imaging), but the systematic error was smaller and more constant in the case of Doppler myocardial imaging over the range of different true volumes.en
dc.description.abstractIn vivo, the study was designed to compare the accuracy of grey-scale and Doppler myocardial imaging three-dimensional left ventricular volume measurements and cineventriculography. The differences were significantly smaller for the Doppler technique during both end-diastole and end-systole. A series of congenital heart lesions has also been studied. It has been shown that dynamic surgical reconstruction of the secundum atrial septal defect is feasible from the transthoracic approach in all patients. However, in adults, Doppler myocardial imaging proved more effective than grey-scale imaging in the accuracy of threedimensional defect reconstruction. In patients with sinus venosus atrial septal defect, transthoracic three-dimensional echocardiography was more accurate than standard echocardiography in diagnosing the defect including a detailed description of the abnormal pulmonary venous drainage. Finally, in children with atrio-ventricular septal defects, the 'unroofed' atrial reconstruction of the common valve accurately displayed dynamic valve morphology en face and the mechanism of valve reflux.en
dc.publisherThe University of Edinburghen
dc.relation.ispartofAnnexe Thesis Digitisation Project 2017 Block 15en
dc.relation.isreferencedbyen
dc.titleThree-dimensional echocardiography for the assessment of congenital and acquired heart diseaseen
dc.typeThesis or Dissertationen
dc.type.qualificationlevelDoctoralen
dc.type.qualificationnameMD Doctor of Medicineen


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