الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
During the past 55 years, there has been an explosive growth in development of various medical imaging techniques, namely, Computerized Tomography (CT), digital radiography, Magnetic Resonance Imaging (MRI), and ultrasound, among others. Ultrasound is particularly suited to situations where exposure to ionizing radiation is undesirable, such as in obstetrics and neonatal monitoring, and to imaging moving structures such as heart valves. Ultrasound has been one of greatest advances for Obstetrics and Gynecology in the last fifty years. From crude initial studies in the 1950’s to the more sophisticated exams of today, Ultrasound has been a great help to physicians and patients. It has found applications in diagnosing multiple gestations, ectopic pregnancy, fetal well being evaluation and detections of fetal abnormalities. 3D-ultrasound imaging is a very new technology. An examiner firstly takes 2D ultrasound images of foetus £rom various angles, and then uses computer technology to combine them into a 3D image.
In this thesis, application of volume rendering in medical ultrasonic imaging is explored. A new technique for direct volume rendering depending on opacity is presented. The new technique depends on taking ultrasound scan movies and then cutting it to set number of slices.
The slices are arranged according to their opacity in (£ront- to -back) manner using
2D-texture mapping and composite technique (a.-blending) to get the volumetric scene. It is found that this method may give clinically useful information, which is very difficult to be obtained £rom ordinary 2D ultrasonic images, and in some cases rendering with fine structural details. This technology can clearly show appearance of foetus, bringing surprise to parents-to-be. Outlook defects such as cleft lips, polydactyl or even as tiny as moles can be clearly shown. The 3D ultrasound images, which are the output of the proposed method, are used for clinical diagnostics by sonographer and this method is evaluated for several fetal studies as shown in this
thesis.