A single centre evaluation of the 2019 UK SABR consortium guidelines for primary lung cancer: correlation between Prescription Dose Spillage and inverse Paddick Conformity Index.

Background: The aim of the study was to determine level of agreement between RTOG Conformity Index (RTOG-CI), Paddick Conformity Index (PCI) and Prescription Dose Spillage (PDS) in describing lung stereotactic ablative radiotherapy (SABR) plan conformity; to elucidate any limitations, in practice, of PCI and PDS. International Commission on Radiation Units and Measurements report 91 (ICRU 91) aimed to reduce inconsistencies in dose prescription and normalisation between centres by specifying SABR reporting rules, and suggested using PCI. UK SABR Consortium 2019 guidelines adopted PDS to measure plan quality, but not the PCI.

High-Resolution Computed Tomography Examinations for Chronic Suppurative Lung Disease in Early Childhood: Radiation Exposure and Image Quality Evaluations With Iterative Reconstruction Algorithm Use.

Purpose: High radiosensitivity of children undergoing repetitive computed tomography examinations necessitates the use of iterative reconstruction algorithms in order to achieve a significant radiation dose reduction. The goal of this study is to compare the iDose iterative reconstruction algorithm with filtered backprojection in terms of radiation exposure and image quality in 33 chest high-resolution computed tomography examinations performed in young children with chronic bronchitis.

Methods: Fourteen patients were scanned using the filtered backprojection protocol while 19 patients using the iDose protocol and reduced milliampere-seconds, both on a 64-detector row computed tomography scanner.

Introduction of an effective method for the optimization of CT protocols using iterative reconstruction algorithms: comparison with patient data.

Objective: The purpose of this study is to introduce an efficient method for the optimization of iterative reconstruction CT protocols based on phantom image analysis and the comparison of obtained results with actual patient data.

Materials And Methods: We considered chest, abdomen, and pelvis CT examinations before the installation of an iterative reconstruction algorithm (iDose4) to define the exposure parameters used in clinical routine with filtered back projection (FBP). The body area of a CT phantom was subsequently scanned with various tube voltages and tube currents-exposure time products, and acquired data were reconstructed with FBP and different levels of iDose4.

Effect of iDose4 iterative reconstruction algorithm on image quality and radiation exposure in prospective and retrospective electrocardiographically gated coronary computed tomographic angiography.

Objectives: The aims of this study were to compare a commercially available reconstruction algorithm (iDose4) with filtered back projection (FBP) in terms of image quality (IQ) for both retrospective electrocardiographically gated and prospective electrocardiographically triggered cardiac computed tomographic angiography (CCTA) protocols and to evaluate the achievable radiation dose reduction.

Methods: A total cohort of 58 patients underwent either prospective CTCA or retrospective CTCA with full or reduced tube current-time product (in milliampere-second) protocol on a 64-slice multidetector computed tomographic scanner. All images were reconstructed with FBP, whereas the reduced milliampere-second images were also reconstructed using 2 levels (levels 4 and 6) of iDose4.

Computed tomography radiation dosimetry: from the indicators to the indications.

The technological advances in computed tomography (CT) scanners and their continuously increased use have raised concern about the patient-induced risks from the CT procedures. In the present review, all available dose metrics used in CT dosimetry are described, evaluated, and compared. The various models and methodologies currently existing for the estimation of the effective dose and, by extension, the carcinogenesis probability as well as the way that this is derived from dose descriptors are also considered.

Radiation dose and image noise evaluation in coronary computed tomography angiography (CCTA) using an iterative reconstruction algorithm.

Introduction: The purpose of this study was to evaluate radiation dose reduction in coronary computerised tomography angiography (CCTA), using a commercially available iterative reconstruction (IR) algorithm as well as the behaviour of the image noise.

Methods: A total cohort of 47 patients underwent CCTA examination on a 64-slice multi-detector CT. They were divided into four groups according to the time when the examination was performed (before or after the installation of iDose) and the acquisition protocol followed (prospective or retrospective electrocardiography-ECG gated).

A new era in computed tomographic dose optimization: the impact of iterative reconstruction on image quality and radiation dose.

The ongoing evolution of computer technology has made the use of iterative reconstruction (IR) algorithms clinically applicable. We reviewed current literature on the clinical use of IR against filtered back projection algorithms in terms of image quality and radiation dose. Iterative reconstruction algorithms provide equal or better image quality compared with filtered back projection, with dose reduction ranging from 25% to 98.

Patient radiation exposure and image quality evaluation with the use of iDose4 iterative reconstruction algorithm in chest-abdomen-pelvis CT examinations.

The aim of this study is to evaluate the effect of iDose(4) iterative reconstruction algorithm on radiation dose and imaging quality at chest-abdomen-pelvis (CAP) CT examinations. Seventeen patients were considered; all patients had a previous CT scan with the standard filter back-projection (FBP) protocol and a follow-up scan with the iDose(4) protocol at the same scanner. Image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were objectively calculated.

Anatomy- vs. fluence-based planning for prostate cancer treatments using VMAT.

The purpose of this study was to compare the planning approaches used in two treatment planning systems (TPS) provided by Elekta for VMAT treatments. Ten prostate patients were studied retrospectively. Plan comparison was performed in terms of delivery efficiency and accuracy, as well as in terms of target coverage and critical organ protection by utilizing physical and radiobiological indices.

Comparative performance evaluation of a flat detector and an image intensifier angiographic system both used for interventional cardiology procedures in adult and pediatric patients.

Purpose: To compare two angiography systems of different image capture technology, one with flat detector (FD) and one with image intensifier (II), in terms of entrance surface air kerma (ESAK) rate, detector dose (DD) rate and image quality (IQ), in interventional cardiology procedures concerning both adult and pediatric patients.

Materials And Methods: In order to determine ESAK and DD rates, a digital dosimeter and polymethylmethacrylate (PMMA) plates were used. For the evaluation of IQ, two contrast objects (the Leeds TOR 18FG and a 5 mm-thick Aluminum plate) were used and two figures of merit were defined in fluoroscopy and cine acquisition modes.