Background: Worldwide the computed tomography (CT) scanning is recognized as a high radiation dose modality. This article aimed to estimate the radiation dose reduction and radiogenic risks for adult patients undertaking abdominal CT examinations. Materials and Methods: A total of 128 patients were studied using 2, 4, 16 and 64 slice CT scanners. The patients were divided into two categories: t...

Objective. This study aims to assess the impact of adaptive statistical iterative reconstruction (ASIR) on CT imaging quality, diagnostic interpretability, and radiation dose reduction for a proven CT acquisition protocol for total body trauma. Methods. 18 patients with multiple trauma (ISS ≥ 16) were examined either with a routine protocol (n = 6), 30% (n = 6), or 40% (n = 6) of iterative reco...

submission for Workshop on Solving Computational Challenges in Medical Imaging – July 2007 Targeted Statistical Image Reconstruction for Cardiac CT Imaging Adam Alessio, PhD, [email protected] Department of Radiology University of Washington Purpose: Current computed tomography (CT) systems generate images with analytic tomographic reconstruction methods because they are simple to imple...

conclusion attending radiologists could diagnose acute appendicitis accurately on ne-ldct. performance of senior residents on ne-ldct is better than junior residents and comparable to attending radiologists. results diagnostic performances for acute appendicitis were not statistically different for attending radiologists at both examinations. better performance was noted on the ce-sdct with a b...

Background: Polymer gel dosimeters combined with magnetic resonance imaging (MRI) can be used for dose verification of advanced radiation therapy techniques. However, the uncertainty of dose map measured by gel dosimeter should be known. The purpose of this study is to investigate the uncertainty related to calibration curve and MRI protocol for MAGIC (Methacrylic and Ascorbic acid in Gelatin I...

Objective To describe the quantitative image quality and histogram-based evaluation of an iterative reconstruction (IR) algorithm in chest computed tomography (CT) scans at low-to-ultralow CT radiation dose levels. Materials and Methods In an adult anthropomorphic phantom, chest CT scans were performed with 128-section dual-source CT at 70, 80, 100, 120, and 140 kVp, and the reference (3.4 mG...

OBJECTIVE To investigate image quality and radiation dose of CT colonography (CTC) with adaptive iterative dose reduction three-dimensional (AIDR3D). METHODS Ten segments of porcine colon phantom were collected, and 30 pedunculate polyps with diameters ranging from 1 to 15 mm were simulated on each segment. Image data were acquired with tube voltage of 120 kVp, and current doses of 10 mAs, 20...

The detection limitations inherent in statistically limited computed tomographic (CT) images are described through the application of signal detection theory. The detectability of large-area, low-contrast objects is shown to be chiefly dependent upon the low-frequency content of the noise power spectral density. For projection data containg uncorrelated noise, the resulting ramplike, low-freque...

background: the shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. these methods include lead standard blocks, individual molding and multi leaf collimator (mlc). the mlc method is not still common in iran radiotherapy centers. individual molding is better than the lead block shield...