Search results for "TPA"
showing 10 items of 770 documents
Assessment of coronary artery bypass grafts: value of different breath-hold MR imaging techniques.
1999
Our aim was to evaluate the patency of coronary artery bypass grafts and to detect graft stenosis using different breath-hold MR imaging techniques.Twenty-two patients with 59 grafts (14 internal mammary artery grafts and 45 saphenous vein grafts) and 76 distal anastomoses (singular and sequential grafts) were studied using a 1.5-T scanner. A two-dimensional T2-weighted breath-hold half-Fourier acquisition single-shot turbo spin echo (HASTE) sequence and a three-dimensional breath-hold contrast-enhanced MR angiography sequence (fast imaging with steady-state free precession) were performed. For MR angiography, a bolus of 20 ml of gadopentetate dimeglumine was used. Time delay for contrast i…
Late gadolinium enhancement-cardiovascular magnetic resonance identifies coronary artery disease as the aetiology of left ventricular dysfunction in …
2009
Aims We evaluated the ability of late gadolinium enhancement (LGE) using cardiovascular magnetic resonance (CMR) to identify acute new-onset heart failure (HF) with left ventricular systolic dysfunction (LVSD), whether or not in relation to underlying coronary artery disease (CAD), in patients with no clinical evidence of associated ischaemic cardiomyopathy. Methods and results Hundred consecutive patients admitted with acute new-onset decompensated HF and EF ,40%, with no clinical or electrocardiographic data suggestive of CAD. The patients were classified according to the presence or absence of significant CAD (stenosis � 70% in at least one major vessel). Twenty-one patients (21%) had si…
Hepatobiliary phase hypointensity predicts progression to hepatocellular carcinoma for intermediate-high risk observations, but not time to progressi…
2020
Purpose: To determine whether hepatobiliary phase hypointensity, enhancing “capsule” and size provide prognostic information regarding the risk of progression to hepatocellular carcinoma (HCC), as well as the time to progression, of intermediate to high risk observations ≥ 10 mm with arterial phase hyperenhancement (APHE). Method: This retrospective dual-institution study included 160 LR-3 and 26 LR-4 observations measuring more than 10 mm and having APHE in 136 patients (mean age [SD], 57 [11] years old). A composite reference standard of pathologic analysis and imaging follow-up was used. The prognostic performance of hepatobiliary phase hypointensity, enhancing “capsule” and size (cut-of…
Myocardial contrast echocardiography in biopsy-proven primary cardiac amyloidosis.
2008
Abstract Cardiac vasculature is affected in 88-90% of patients with primary cardiac amyloidosis (CA). Myocardial contrast echocardiography (MCE) relies on the ultrasound detection of microbubble contrast agents that are solely confined to the intravascular space, and are therefore useful in the evaluation of flow in the microvasculature. This is the first case report describing the use of MCE during vasodilator stress to evaluate coronary flow reserve in a patient with biopsy-proven primary CA and angiographically normal coronaries. Qualitative MCE demonstrated delayed replenishment of microbubbles during peak stress; quantitative analysis was consistent with a reduction in total myocardial…
Role of Cardiac Magnetic Resonance Imaging in the Detection of Cardiac Amyloidosis
2010
Objectives Our aim was to evaluate the role and mechanism of late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) in identifying cardiac amyloidosis (CA) and to investigate associations between LGE and clinical, morphologic, functional, and biochemical features. Background CA can be challenging to diagnose by echocardiography. Recent studies have demonstrated an emerging role for LGE-CMR. Methods LGE-CMR was performed in 120 patients with amyloidosis. Cardiac histology was available in 35 patients. The remaining 85 patients were divided into those with and without echocardiographic evidence of CA. Results Of the 35 patients with histologically verified CA, abnormal LGE was pre…
Utility of Cardiac Magnetic Resonance to assess association between admission hyperglycemia and myocardial damage in patients with reperfused ST-segm…
2008
Abstract Aims to investigate the association between admission hyperglycemia and myocardial damage in patients with ST-segment elevation myocardial infarction (STEMI) using Cardiac Magnetic Resonance (CMR). Methods We analyzed 113 patients with STEMI treated with successful primary percutaneous coronary intervention. Admission hyperglycemia was defined as a glucose level ≥ 7.8 mmol/l. Contrast-enhanced CMR was performed between 3 and 7 days after reperfusion to evaluate left ventricular function and perfusion data after injection of gadolinium-DTPA. First-pass images (FP), providing assessment of microvascular obstruction and Late Gadolinium Enhanced images (DE), reflecting the extent of in…
Cellular uptake and in vitro antitumor efficacy of composite liposomes for neutron capture therapy.
2014
Background Neutron capture therapy for glioblastoma has focused mainly on the use of 10B as neutron capture isotope. However, 157Gd offers several advantages over boron, such as higher cross section for thermal neutrons and the possibility to perform magnetic resonance imaging during neutron irradiation, thereby combining therapy and diagnostics. We have developed different liposomal formulations of gadolinium-DTPA (Magnevist®) for application in neutron capture therapy of glioblastoma. The formulations were characterized physicochemically and tested in vitro in a glioma cell model for their effectiveness. Methods Liposomes entrapping gadolinium-DTPA as neutron capture agent were manufactur…
MRI-Visible Poly(ε-caprolactone) with Controlled Contrast Agent Ratios for Enhanced Visualization in Temporary Imaging Applications
2013
International audience; Hydrophobic macromolecular contrast agents (MMCAs) are highly desirable to provide safe and efficient magnetic resonance (MR) visibility to implantable medical devices. In this study, we report on the synthesis and evaluation of novel biodegradable poly(ε-caprolactone)-based MMCAs. Poly(α-propargyl-ε-caprolactone-co-ε-caprolactone)s containing 2, 5, and 10 mol % of propargyl groups have been prepared by ring-opening copolymerization of ε-caprolactone and the corresponding propargylated lactone. In parallel, a diazido derivative of the clinically used diethylenetriaminepentaacetic acid (DTPA)/Gd3+ complex has been synthesized. Finally, MRI-visible poly(ε-caprolactone)…
Quantification of pulmonary blood flow (PBF): validation of perfusion MRI and nonlinear contrast agent (CA) dose correction with H(2)15O positron emi…
2009
Validation of quantification of pulmonary blood flow (PBF) with dynamic, contrast-enhanced MRI is still missing. A possible reason certainly lies in difficulties based on the nonlinear dependence of signal intensity (SI) from contrast agent (CA) concentration. Both aspects were addressed in this study. Nine healthy pigs were examined by first-pass perfusion MRI using gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) and HO positron emission tomography (PET) imaging. Calculations of hemodynamic parameters were based on a one-compartment model (MR) and a two-compartment model (PET). Simulations showed a significant error when assuming a linear relation between MR SI and CA dose in the …
Benign and malignant mimickers of infiltrative hepatocellular carcinoma: tips and tricks for differential diagnosis on CT and MRI
2021
Hepatocellular carcinoma (HCC) may have an infiltrative appearance in about 8-20% of cases. Infiltrative HCC can be a challenging diagnosis and it is associated with the worst overall survival among HCC patients. Infiltrative HCC is characterized by the spread of multiple minute nodules throughout the liver, without a dominant one, ultimately resulting into macrovascular invasion. On CT and MRI, infiltrative HCC appears as an ill-defined, large mass, with variable degree of enhancement, and satellite neoplastic nodules in up to 52% of patients. On MRI, it may show restriction on diffusion weighted imaging, hyperintensity on T2- and hypointensity on T1-weighted images, and, if hepatobiliary …