The advanced single–slice rebinning algorithm (ASSR) is a highly accurate and efficient approximative algorithm for cone–beam spiral CT that a) yields high image quality even at large cone angles, b) makes use of available 2D backprojection algorithms/hardware and c) allows for sequential data processing. It uses virtual R–planes (reconstruction planes) that are tilted to optimally fit 180 spir...

X-ray CT images have been widely used in clinical diagnosis in recent years. A modern CT scanner can generate about 1000 CT slices to show the details of all the human organs within 30 seconds. However, CT image interpretations (viewing 500-1000 slices of CT images manually in front of a screen or films for each patient) require a lot of time and energy. Therefore, computer–aided diagnosis (CAD...

OBJECTIVES This study aimed to measure the absorbed doses in selected organs for prospectively ECG-triggered coronary computed tomography angiography (CCTA) using five different generations CT scanners in a female adult anthropomorphic phantom and to estimate the effective dose (HE). MATERIALS AND METHODS Prospectively ECG-triggered CCTA was performed using five commercially available CT scan...

OBJECTIVES We evaluated the accuracy of a new 64-slice computed tomography (CT) scanner, compared with intravascular ultrasound, to visualize atherosclerosis in the proximal coronary system. BACKGROUND Noninvasive determination of plaque composition and plaque burden may be important to improve risk stratification. METHODS In 20 patients, a 64-slice CT scan (Sensation 64, Siemens Medical So...

combined pet/ct scanners now play a major role in medicine for in vivo imaging in oncology, cardiology, neurology, and psychiatry. as the performance of a scanner depends not only on the scintillating material but also on the scanner design, with regards to the advent of newer scanners, there is a need to optimize acquisition protocols as well as to compare scanner performances on an objective ...

The purpose of bowtie filters in CT scanners is to homogenize the x-ray intensity measured by the detectors in order to improve the image quality and at the same time to reduce the dose to the patient because of the preferential filtering near the periphery of the fan beam. For CT dosimetry, especially for Monte Carlo calculations of organ and tissue absorbed doses to patients, it is important ...

BACKGROUND The use of pediatric CT that had recently emerged as a valuable imaging tool has increased rapidly with an annual growth estimated at about 10% per year. Worldwide, there is a remarkable increase in the number of CT examinations performed. The purposes of this study are to: (i) to measure the radiation dose and estimate the effective doses to pediatric patients during CT for chest, a...

An approach for automatic classification of computed tomography (CT) medical images is presented in this paper. A vast amount of CT images are produced in modern hospitals due to advances of multi-slice Computed Tomography (CT) Scan which handles up to 64 slices per scan. So, an input image based automatic medical image retrieval system is now a necessity. In this paper, Coiflet wavelets are us...

AIMS The aim of this study was to evaluate the diagnostic accuracy in the assessment of coronary artery bypass grafts using 64-slice computed tomography (CT) technology. METHODS AND RESULTS CT coronary angiography was performed for 96 bypasses in 31 patients with suspected coronary artery disease using a Siemens Sensation 64-slice CT-scanner and compared with invasive coronary angiography (IC...

This study evaluated the compressibility of multislice CT (MSCT) datasets and its dependence on (1) slice thickness and (2) the use of three-dimensional (3D) vs. 2D JPEG2000 compression methods. Five thoracic CT datasets were obtained using a 16-detector MSCT scanner with a collimation of 0.75 mm (120 kVp, 90 mAs) and reconstructed at five slice thicknesses from 0.75 to 10.0 mm. These datasets ...