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The aim of the study was to investigate the relationship of radiation dose and image quality in 3D multidetector computed tomography (CT) angiography of abdominal aortic aneurysm based on an aorta phantom. The study was conducted using a human aorta phantom modelled on a patient with an abdominal aortic aneurysm. To perform the scans of the aorta phantom, it was placed in a specially designed, sealable perspex container, which was filled with iodinated contrast medium. A series of scans was performed using different protocols to test the effect on dose and image quality. These were: the variable detectors (4-, 32- and 64-slice) used in image acquisition, x-ray tube current (mA) and pitch values. A line profile analysis was conducted at three separate locations for each different protocol, namely: the renal artery, superior mesenteric artery, and abdominal aortic aneurysm to determine the degree of image artefacts using standard deviation, which was measured on the virtual intravascular endoscopy images. The effective dose was also calculated for each scanning protocol. The results indicate that the scans performed on 64 detectors multidetector CT produce better image quality compared to 32 and 4 detectors. Increasing scanning parameters such as mA enhances image quality but it also increases the patient's radiation dose. It is also noted that the pitch is inversely proportional to radiation dose, resulting in degradation of image quality. From these results, a 64 multidetector CT scanner with a scanning protocol of 120 kVp, 70 mA, and a pitch of 0.641 is ideal for imaging of abdominal aortic aneurysms because it allows for fewer artefacts and less radiation dose when compared to other scanning protocols. (author abstract)