Search results for "COMPUTED TOMOGRAPHY"
showing 10 items of 713 documents
Parameters for coronary plaque vulnerability assessed with multidetector computed tomography and intracoronary ultrasound correlation
2009
In the absence of a fixed relationship between plaque vulnerability and flow-limiting stenosis, alternative morphological expressions exist that could predict the liability of coronary lesions to rapidly progress or rupture, causing acute coronary syndromes. Modern multidetector computed tomography technology is capable of noninvasively detecting lesion location, attenuation, remodeling and calcification pattern, which may be considered as surrogate morphological markers of vulnerability and could contribute to increase the prognostic value of individual coronary plaque burden. J Cardiovasc Med 10:821 -826 (C) 2009 Italian Federation of Cardiology.
Familial resemblance and diversity in bone mass and strength in the population are established during the first year of postnatal life
2010
Familial resemblance and diversity in bone structure and strength in adulthood are determined in part during growth. Whether these characteristics are established during gestation or shortly after birth is not known. Total-body, lumbar spine, and femoral neck size and mass and indices of tibial bending strength and distal radial compressive strength were measured using bone densitometry and quantitative computed tomography in 236 girls at 18.5 years of age. Among them, 219, 141, and 105 girls had crown-heel length (CHL) and weight recorded at birth and at 6 and 12 months of age, and then height and weight were recorded at 3, 5, 10, 13, and 15 years of age in 181, 176, 127, 111, and 228 girl…
016: Evidence of systemic plaque vulnerability in acute coronary syndromes with FDG-positron emission tomography and computed tomographic angiography…
2013
PurposeAtherosclerotic plaque vulnerability is a systemic phenomenon and is often associated with severe plaque infiltration with inflammatory cells. 18-Fluoro-deoxyglucose (FDG) accumulates in inflammatory cells of atherosclerotic plaques. The aim of this study was to assess whether 1) FDG uptake in the aorta and carotid arteries measured by positron emission tomography (PET) is higher in patients with acute coronary syndromes (ACS) than in patients with stable coronary artery disease (CAD) and; 2) associated with morphological markers of plaque instability detected with computed tomography angiography (CTA).MethodsPatients with ACS (n=50) or stable CAD (n=28) underwent a PET 90 minutes af…
3D reconstruction techniques made easy: know-how and pictures
2005
Three-dimensional reconstructions represent a visual-based tool for illustrating the basis of three-dimensional post-processing such as interpolation, ray-casting, segmentation, percentage classification, gradient calculation, shading and illumination. The knowledge of the optimal scanning and reconstruction parameters facilitates the use of three-dimensional reconstruction techniques in clinical practise. The aim of this article is to explain the principles of multidimensional image processing in a pictorial way and the advantages and limitations of the different possibilities of 3D visualisation.
Computational fluid dynamics simulation to evaluate aortic coarctation gradient with contrast-enhanced CT
2014
Coarctation of aorta (CoA) is a narrowing of the aorta leading to a pressure gradient (Delta P) across the coarctation, increased afterload and reduced peripheral perfusion pressures. Indication to invasive treatment is based on values of maximal (systolic) trans-coarctation Delta P. A computational fluid dynamic (CFD) approach is herein presented for the non-invasive haemodynamic assessment of Delta P across CoA. Patient-specific CFD simulations were created from contrast-enhanced computed tomography (CT) and appropriate flow boundary conditions. Computed Delta P was validated with invasive intravascular trans-CoA pressure measurements. Haemodynamic indices, including pressure loss coeffic…
Relationship of sex hormones to bone geometric properties and mineral density in early pubertal girls.
2004
This study aimed to evaluate the associations among serum 17beta-estradiol (E2), testosterone (T), sex hormone-binding globulin (SHBG), bone geometric properties, and mineral density in 248 healthy girls between the ages of 10 and 13 yr old. The left tibial shaft was measured by peripheral quantitative computed tomography (Stratec XCT-2000; Stratec Medizintechnik, GmbH, Pforzheim, Germany). The cortical bone and marrow cavity areas were expressed as proportions of the total tibial cross-sectional area (CSA). Cortical thickness and total volumetric bone mineral density (vBMD) were also determined. These tibial geometric and densitometric measures were correlated against the serum sex hormone…
Relation of PvuII site polymorphism in the COL1A2 gene to the risk of fractures in prepubertal Finnish girls.
2003
Genetic susceptibility to fractures may be detectable in early childhood. We evaluated the associations between the polymorphic PvuII site of the COL1A2 gene and bone properties assessed by different modalities (dual-energy X-ray absorptiometry; peripheral quantitative computed tomography; gel coupling scanning quantitative ultrasonometry; ultrasound bone sonometry), bone turnover markers, and the occurrence of fractures in 244 prepubertal Finnish girls. Tanner stage and physical characteristics did not differ significantly among girls with different COL1A2 genotypes. The polymorphism was not significantly associated with different bone properties or any of the bone turnover markers when gi…
Myocardial blood flow quantification for evaluation of coronary artery disease by computed tomography
2017
During the last decade coronary computed tomography angiography (CTA) has become the preeminent non-invasive imaging modality to detect coronary artery disease (CAD) with high accuracy. However, CTA has a limited value in assessing the hemodynamic significance of a given stenosis due to a modest specificity and positive predictive value. In recent years, different CT techniques for detecting myocardial ischemia have emerged, such as CT-derived fractional flow reserve (FFR-CT), transluminal attenuation gradient (TAG), and myocardial CT perfusion (CTP) imaging. Myocardial CTP imaging can be performed with a single static scan during first pass of the contrast agent, with monoenergetic or dual…
Technical development in cardiac CT: current standards and future improvements—a narrative review
2020
Non-invasive depiction of coronary arteries has been a great challenge for imaging specialists since the introduction of computed tomography (CT). Technological development together with improvements in spatial, temporal, and contrast resolution, progressively allowed implementation of the current clinical role of the CT assessment of coronary arteries. Several technological evolutions including hardware and software solutions of CT scanners have been developed to improve spatial and temporal resolution. The main challenges of cardiac computed tomography (CCT) are currently plaque characterization, functional assessment of stenosis and radiation dose reduction. In this review, we will discu…
Elevated systolic pulmonary artery pressure for prediction of myocardial necrosis and right ventricular dysfunction in acute pulmonary embolism
2016
Kontext: Echokardiografie je v soucasnosti hlavni metodou pro vysetřeni dysfunkce prave komory (right ventricular dysfunction, RVD) u akutni plicni embolie (PE). Dysfunkce prave komory je sice spojena s nepřiznivou prognozou, dosud vsak nebyla přijata žadna obecně uznavana definice. Systolický tlak v plicnici (systolic pulmonary artery pressure, sPAP) větsinou neni soucasti kriterii RVD. Cilem nasi studie bylo zhodnotit možnost použiti sPAP v predikci nekrozy myokardu a RVD u akutni PE.Metody: Retrospektivně byly analyzovany udaje 182 pacientů s akutni PE. Pacienti s PE a hodnotami sPAP ≤ 30 mm Hg byli srovnavani s pacienty s PE a hodnotami sPAP > 30 mm Hg. Vztahy mezi sPAP na jedne straně …