Search results for " CT"

Patient centring and scan length: how inaccurate practice impacts on radiation dose in CT colonography (CTC).

2019

Objective: The aim of this study was to acknowledge errors in patients positioning in CT colonography (CTC) and their effect in radiation exposure. Materials and methods: CTC studies of a total of 199 patients coming from two different referral hospitals were retrospectively reviewed. Two parameters have been considered for the analysis: patient position in relation to gantry isocentre and scan length related to the area of interest. CTDI vol and DLP were extracted for each patient. In order to evaluate the estimated effective total dose and the dose to various organs, we used the CT-EXPO ® software version 2.2. This software provides estimates of effective dose and doses to the other vario…

Quadruple-Phase MDCT of the Liver in Patients with Suspected Hepatocellular Carcinoma: Effect of Contrast Material Flow Rate

2006

The purposes of this study were to evaluate the effect of contrast material flow rate (3 mL/sec vs 5 mL/sec) on the detection and visualization of hepatocellular carcinoma (HCC) with MDCT and the safety profile of iodixanol at different injection rates.In a prospective, randomized multicenter trial, 97 patients (83 men and 14 women, with a mean age of 64 years) suspected of having HCC underwent quadruple-phase (double arterial, portal venous, delayed phase) 4-16-MDCT. Patients were randomized to receive iodixanol, 320 mg I/mL (1.5 mL/kg body weight), at a flow rate of 3 mL/sec (48 patients) or 5 mL/sec (49 patients). Qualitative (lesion detection, image quality) and quantitative (liver and …

Physiopathology of the aging heart.

2008

Coronary heart disease remains the leading cause of morbidity and mortality in older adults, despite improved survival and declining mortality. Prevalence in and impact of heart disease on elderly people, increasing risk factors, and the underlying physiologic changes of aging are briefly reviewed. High prevalence of clinical and subclinical heart disease provides a basis for considering opportunities for prevention and follow-up. This article focuses on recently developed noninvasive techniques, such as cardiac multislice CT and cardiac MR imaging.

ECG-GATED MULTIDETECTOR COMPUTED TOMOGRAPHY FOR THE ASSESSMENT OF THE POSTOPERATIVE ASCENDING AORTA

2009

This study was undertaken to define the role of electrocardiographically (ECG)-gated multidetector computed tomography (MDCT) in the assessment of the postoperative ascending aorta. From November 2006 to June 2007, 21 patients, [11 men, ten women; age +/- standard deviation (SD): 62.7 +/- 10.8 years] with a history of ascending aorta replacement underwent ECG-gated MDCT and were prospectively included in our study. Ascending aorta replacement had been performed with different surgical techniques: Bentall-De Bono (four patients, 19%), Tirone-David (five patients, 23%), and modified Tirone-David with creation of aortic neosinuses (12 patients, 57%). Two patients were excluded from MDCT evalua…

Incidence of new foci of hepatocellular carcinoma after radiofrequency ablation: role of multidetector CT

2012

Purpose. The authors sought to assess the incidence of new foci of hepatocellular carcinoma (HCC) using multidetector computed tomography (MDCT) in patients treated with radiofrequency ablation (RFA). Materials and methods. Two readers retrospectively reviewed by consensus the follow-up MDCT studies of 125 patients (88 men and 37 women; mean age 68 years) with 141 HCCs (size 1–5.2 cm; mean 2.2 cm) treated with RFA. MDCT follow-up was performed at 1 and 3 months and every 6–12 months thereafter. Reviewers assessed: (1) the presence of new HCC foci in the same liver segment or in a different segment; (2) complete or incomplete tumor ablation; (3) tumour progression. Results. A total of 113 ne…

Fatal venous air embolism: proof and volumetry by helical CT

1995

Three-Dimensional Contrast-Enhanced Magnetic Resonance Angiography in a Patient With Chronic Thromboembolic Pulmonary Hypertension Before and After T…

1999

The patient was a 69-year-old man with progressive dyspnea during the previous 5 years and no history of thromboembolic events. By means of spiral CT scanning and multiplanar digital subtraction angiography of the pulmonary arteries, chronic thromboembolic pulmonary hypertension was diagnosed. Mean pulmonary artery pressure and pulmonary vascular resistance were elevated to 46 mm Hg and 890 …

Imaging processing for CT angiography of the cervicocranial arteries: evaluation of reformatting technique.

2007

Purpose. The aim of this study was to compare computed tomography angiography (CTA) sliding-thin-slab (STS) multiplanar reformatting (MPR), STS maximum intensity projection (MIP) and three-dimensional (3D) volume rendering (VR) reformatting techniques in the evaluation of cervicocranial arteries. Materials and methods. Twenty patients examined with multislice CT were included in this study. CTA images were reformatted as STS-MIP, STS-MPR and 3DVR in orthogonal planes and in the oblique-coronal plane. Images were evaluated in consensus by two radiologists, with a third radiologist to resolve discordances in grading image quality parameters. The Spearman correlation analysis was performed to …

Radiation dose from multidetector CT studies in children: results from the first Italian nationwide survey

2014

Background Multidetector CT (MDCT) scanners have con- tributed to the widespread use of CT in paediatric imaging. However, concerns are raised for the associated radiation exposure. Very few surveys on radiation exposure from MDCT studies in children are available. Objective The aim of this study was to outline the status of radiation exposure in children from MDCT practice in Italy. Materials and methods In this retrospective multicentre study we asked Italian radiology units with an MDCT scanner with at least 16 slices to provide dosimetric and acquisition param- eters of CT examinations in three age groups (1–5, 6–10, 11– 15 years) for studies of head, chest and abdomen. The dosi- metric…

Role of cardiac computed tomography in the evaluation of coronary artery stenosis in patients with ascending aorta aneurysm detected at transthoracic…

2016

OBJECTIVE The aim of our study was to evaluate the diagnostic performance of cardiac computed tomography (CCT) in the evaluation of coronary artery stenosis in patients with ascending aorta aneurysm detected at transthoracic echocardiography. METHODS We conducted a retrospective analysis of patients with an aneurysm 45 mm or greater at transthoracic echocardiography who underwent CCT from 2012 to 2014 in our hospital. We calculated the sensitivity, specificity, and positive and negative predictive values of CCT for the assessment of coronary artery stenosis (<50% or ≥50% stenosis) in patients who underwent conventional coronary angiography. RESULTS We included 104 patients (73 men, aged 64 …