Search results for "MRI"
showing 10 items of 733 documents
Multiparametric 18F-FDG PET-MRI of the breast: are there differences in imaging biomarkers of contralateral healthy tissue between patients with and …
2019
The rationale was to assess whether there are differences in multiparametric 18F-FDG PET/MRI biomarkers of contralateral healthy breast tissue in patients with benign and malignant breast tumors. Methods: In this institutional review board-approved prospective single-institution study, 141 women with imaging abnormalities on mammography or sonography (BI-RADS 4/5) underwent combined 18F-FDG PET/MRI of the breast at 3T with dynamic contrast-enhanced MRI, diffusion-weighted imaging, and the radiotracer 18F-FDG. In all patients, the following imaging biomarkers were recorded for the contralateral (tumor-free) breast: breast parenchymal uptake (BPU) (from 18F-FDG PET), mean apparent diffusion c…
Information transfer and information modification to identify the structure of cardiovascular and cardiorespiratory networks
2017
To fully elucidate the complex physiological mechanisms underlying the short-term autonomic regulation of heart period (H), systolic and diastolic arterial pressure (S, D) and respiratory (R) variability, the joint dynamics of these variables need to be explored using multivariate time series analysis. This study proposes the utilization of information-theoretic measures to measure causal interactions between nodes of the cardiovascular/cardiorespiratory network and to assess the nature (synergistic or redundant) of these directed interactions. Indexes of information transfer and information modification are extracted from the H, S, D and R series measured from healthy subjects in a resting…
Quantitative contrast-enhanced myocardial perfusion magnetic resonance imaging: Simulation of bolus dispersion in constricted vessels
2009
Quantification of myocardial blood flow (MBF) by means of T 1 -weighted first-pass magnetic resonance imaging(MRI) requires knowledge of the arterial input function (AIF), which is usually estimated from the left ventricle (LV). Dispersion of the contrast agent bolus may occur between the LV and the tissue of interest, which leads to systematic underestimation of the MBF. The aim of this study was to simulate the dispersion along a simplified coronary artery with different stenoses. To analyze the dispersion in vessels with typical dimensions of coronary arteries, simulations were performed using the computational fluid dynamics approach. Simulations were accomplished on straight vessels wi…
Multiparametric MRI and Radiomics in Prostate Cancer: A Review of the Current Literature
2021
Prostate cancer (PCa) represents the fourth most common cancer and the fifth leading cause of cancer death of men worldwide. Multiparametric MRI (mp-MRI) has high sensitivity and specificity in the detection of PCa, and it is currently the most widely used imaging technique for tumor localization and cancer staging. mp-MRI plays a key role in risk stratification of naïve patients, in active surveillance for low-risk patients, and in monitoring recurrence after definitive therapy. Radiomics is an emerging and promising tool which allows a quantitative tumor evaluation from radiological images via conversion of digital images into mineable high-dimensional data. The purpose of radiomics is to…
Kardio-MRT
2004
Since initial reports in the early 1990s cardiac magnetic resonance imaging (CMR) has matured and is likely to become an established method for routine cardiac diagnostics. The development of faster gradient-echo sequences and stronger magnetic fields has led to improved temporal and spatial resolution. Myocardial viability can be examined by morphological and functional analysis. Contrast enhanced MRI (ceMRI), perfusion measurements and regional wall motion analysis are the major diagnostic tools. The ability to image in arbitrary double oblique planes provides comprehensive visualization of the heart. The introduction of the MR navigator technique allowed for free-breathing motion correct…
Restoring Neurological Physiology: The Innovative Role of High-Energy MR-Guided Focused Ultrasound (HIMRgFUS). Preliminary Data from a New Method of …
2017
Background Tremor is a disabling condition, common to several neurodegenerative diseases. Lesioning procedures and deep brain stimulation, respectively, of the ventralis intermedius nucleus for intentional tremor, and of the subthalamic nucleus for parkinsonian resting tremor, have been introduced in clinical practice for patients refractory to medical treatment. The combination of high-energy focused ultra-sound (HIFUS) with sophisticated magnetic resonance (MR) instrumentation, together with accurate knowledge of the stereotactic brain coordinates, represents a revolution in neuromodulation. Methods At the Neurosurgical Clinic and the Radiology Department of the University of Palermo,, tw…
Neuroanatomical changes in early Parkinson’s disease with mild cognitive impairment: a VBM study; the Parkinson’s Disease Cognitive Impairment Study …
2021
Introduction: Mild cognitive impairment (MCI) is common in Parkinson’s disease (PD), but the underlying pathological mechanism has not been fully understood. Voxel-based morphometry could be used to evaluate regional atrophy and its relationship with cognitive performances in early PD-MCI. Patients and Methods: One hundred and six patients with PD were recruited from a larger cohort of patients, the Parkinson’s Disease Cognitive Impairment Study (PaCoS). Subject underwent a T1-3D MRI and a complete clinical and neuropsychological evaluation. Patients were divided into PD with normal cognition (PD-NC) and PD-MCI according to the MDS level II criteria–modified for PD-MCI. A subgroup of early …
A new window in multiple sclerosis pathology: non-conventional quantitative magnetic resonance imaging outcomes
2010
Recent findings suggest that neuronal pathology occurs early in the course of multiple sclerosis and seems to be responsible for accumulation of disability. Nonetheless, the nervous system has an intrinsic potential for repair and compensation in the neuronal component. Disease-modifying drugs such as glatiramer acetate interfere with, and down-regulate, inflammatory pathology and slow neurodegeneration. Moreover, certain regulatory cytokines and neurotrophic factors have the capacity to promote neuronal and axonal repair. Given the importance of neuronal injury in multiple sclerosis and the potential of certain treatments for neuronal repair, it is important to possess adequate and sensiti…
Eine Mannitollösung als orales Kontrastmittel in der pelvinen MRT
1995
PURPOSE Improvement of pelvic MRI using peroral administration of an aqueous mannitol solution. METHODS We retrospectively evaluated magnetic resonance examinations of 72 patients with suspected or proven pelvic abnormalities: In 36 patients, no bowel marking was carried out. In further 36 patients, we performed a contrast enhancement of the bowel by oral application of 1000 ml of an aqueous mannitol solution. RESULTS 8/36 (22%) patients suffered from diarrhoea, nausea or meteorism as a result of mannitol application. In group 2, an excellent bowel marking of the small intestine could be obtained in 36/36 (100%) patients. Contrast enhancement of the bowel significantly improved delineation …
Detection of central circuits implicated in the formation of novel pain memories
2016
Jaymin Upadhyay,1 Julia Granitzka,1 Thomas Bauermann,2 Ulf Baumgärtner,3 Markus Breimhorst,1 Rolf-Detlef Treede,3 Frank Birklein1 1Department of Neurology, 2Department of Neuroradiology, University Medical Centre, Johannes Gutenberg University Mainz, Mainz, 3Department of Neurophysiology, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Mannheim, Germany Abstract: Being able to remember physically and emotionally painful events in one’s own past may shape behavior, and can create an aversion to a variety of situations. Pain imagination is a related process that may include recall of past experiences, in addition to production of sensor…