Search results for "dynamic"
showing 10 items of 12329 documents
Acute, subchronic and discontinuation effects of zopiclone on sleep EEG and nocturnal melatonin secretion
1996
Zopiclone is a new short half-life cyclopyrrolone hypnotic agent acting at the GABA-benzodiazepine receptor complex. In order to characterize its pharmacological profile, the effects of 7.5 mg zopiclone on nocturnal melatonin secretion were investigated under polysomnographic control in 11 healthy subjects following acute and subchronic administration as well as after abrupt discontinuation of the drug. No effect of zopiclone on the melatonin plasma levels could be observed. Regarding both total melatonin production and the temporal pattern of melatonin secretion during the night, there was no difference between placebo baseline condition, acute and subchronic administration, and discontinu…
Emotional eating and food intake after sadness and joy
2013
Do people with a high score on a scale for eating in response to negative emotions also show high food intake in response to positive emotions?. We studied these effects in 60 female students that were preselected on the basis of extreme high or low scores on an emotional eating questionnaire. Using a between subject design we experimentally tested the difference in food intake following a mood induction designed to induce joy or sadness (the joy vs. sad mood condition). The high and low emotional eaters did not differ in their food intake, but emotional eating significantly moderated the relationship between mood condition and food intake. Whereas low emotional eaters ate similar amounts a…
Enhancement pattern of hepatocellular adenoma (HCA) on MR imaging performed with Gd-EOB-DTPA versus other Gd-based contrast agents (GBCAs): An intrai…
2019
Purpose: To conduct an intraindividual comparison of the enhancement pattern of hepatocellular adenoma (HCA) on dynamic MRI study obtained following the injection of Gadoxetic acid (Gd-EOB-DTPA) and other gadolinium-based contrast agents (GBCAs).Method: This is a retrospective, Institutional Review Board-approved study conducted in a single institution. A search of medical records between 2008 and 2017 revealed 17 patients (all females) with at least one pathologically-proven HCA who underwent liver MRI with Gd-EOB-DTPA and another GBCA within 1 year. Enhancement of each lesion on hepatic arterial (HAP), portal venous (PVP), 2 min and 4-5 minutes phases was subjectively evaluated by two abd…
Gadoxetic acid-enhanced MRI of transient hepatic enhancement differences: Another cause of hypointense observation on hepatobiliary phase
2018
Purpose: To retrospectively determine the frequency, natural history and factors associated with the presence of transient hepatic enhancement difference showing hypointensity on hepatobiliary phase images of gadoxetic acid-enhanced MRI. Materials and methods: Gadoxetic acid-enhanced MRI of 125 patients (91 men; 34 women) with transient hepatic enhancement difference were retrospectively reviewed. Three readers qualitatively and quantitatively evaluated MR imaging features and evolution at follow up. The Chi-square test, Fisher's exact test and Kruskall-Wallis rank test were used for statistical analysis. Results: Transient hepatic enhancement difference were hypointense on hepatobiliary ph…
The Adverse Events and Hemodynamic Effects of Adenosine-Based Cardiac MRI
2011
OBJECTIVE We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. MATERIALS AND METHODS One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 µg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. RESULTS In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patie…
Assessment of tumor microcirculation with dynamic contrast-enhanced MRI in patients with esophageal cancer: initial experience.
2008
PURPOSE: To investigate the feasibility and impact of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) on tumor characterization and response to radiochemotherapy (RCT) in patients with esophageal cancer. MATERIALS AND METHODS: A total of 48 patients underwent DCE-MRI to assess tumor microcirculation based on a two-compartment model function. Effects of RCT on kinetic parameters were studied in 12 patients with squamous cell carcinoma. RESULTS: Tumor microcirculation differs with respect to histological subtype: squamous cell carcinomas showed lower values of amplitude A (leakage space, P = 0.015) and higher contrast agent exchange rates (k(21), P = 0.225) compared with adenoc…
Chronic Thromboembolic Pulmonary Hypertension: Pre- and Postoperative Assessment with Breath-hold MR Imaging Techniques
2004
To evaluate the potential of breath-hold magnetic resonance (MR) imaging techniques in morphologic and functional assessment of patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and after surgery.Thirty-four patients with CTEPH were examined before and after pulmonary thromboendarterectomy (PTE). For morphologic assessment, contrast material-enhanced MR angiography was used; for assessment of hemodynamics, velocity-encoded gradient-echo sequences and cine gradient-echo sequences along the short axis of the heart were performed. Contrast-enhanced MR angiography was compared with selective digital subtraction angiography (DSA) for depiction of central thromboembolic m…
Magnetically labeled water perfusion imaging of the uterine arteries and of normal and malignant cervical tissue: initial experiences.
1998
Purpose: The aim of this pilot study was to evaluate a magnetically labeled water perfusion imaging technique as a non-contrast-enhanced approach to demonstrate the uterine artery, its branches, and to assess the cervical uterine blood flow in healthy volunteers and in patients with advanced uterine cervical carcinoma (FIGO IIB-IVA). Methods and Materials: Seven healthy volunteers (mean age, 29 years) and twenty-two patients (mean age, 52 years) with advanced cancer of the uterine cervix (FIGO IIB-IVA) were prospectively examined by magnetically labeled water perfusion imaging at different inversion delay times (300–900 ms). The magnetic resonance imaging (MRI) findings of all patients were…
Effect of aneurysm on the mechanical dissection properties of the human ascending thoracic aorta
2012
Objectives: The acute dissection of an ascending thoracic aortic aneurysm (ATAA) represents a devastating separation of elastic layers occurring when the hemodynamic loads on the diseased wall exceed the adhesive strength between layers. At present, the mechanics underlying aortic dissection are largely unclear, and the biomechanical delamination properties of the aneurysmal aorta are not defined. Individuals with bicuspid aortic valve (BAV) are particularly predisposed to ascending aortic aneurysm formation, with a marked risk of aortic dissection. The purpose of this study was to evaluate and compare the dissection properties of nonaneurysmal and aneurysmal human ascending thoracic aorta …
3D TOF MR Angiography of Cerebral Arteriovenous Malformations after Radiosurgery
1993
To investigate the potential of three-dimensional time-of-flight MR angiography (MRA) to complement SE imaging, 18 patients with intracerebral arteriovenous malformations were prospectively followed after undergoing radiosurgery. Vessel occlusion after stereotaxic single high dose radiotherapy develops slowly. The MRA detected signs of nidus obliteration earlier and with a higher sensitivity than did SE imaging. Six months after radiosurgery, MRA showed a reduction of the nidus flow signals in nine patients and after 1 year it showed reduction in 15 of the 18 patients. As shown by MRA, the loss of flow signals was related to a reduction of the nidus size in 4 patients after 6 months and in …