Search results for " MRI"

Singlet‐Contrast Magnetic Resonance Imaging: Unlocking Hyperpolarization with Metabolism

2020

Abstract Hyperpolarization‐enhanced magnetic resonance imaging can be used to study biomolecular processes in the body, but typically requires nuclei such as 13C, 15N, or 129Xe due to their long spin‐polarization lifetimes and the absence of a proton‐background signal from water and fat in the images. Here we present a novel type of 1H imaging, in which hyperpolarized spin order is locked in a nonmagnetic long‐lived correlated (singlet) state, and is only liberated for imaging by a specific biochemical reaction. In this work we produce hyperpolarized fumarate via chemical reaction of a precursor molecule with para‐enriched hydrogen gas, and the proton singlet order in fumarate is released a…

Role of apparent diffusion coefficient values in prostate diseases characterization on diffusion-weighted magnetic resonance imaging.

2019

BACKGROUND: To evaluate if normal and pathological prostate tissue can be distinguished by using apparent diffusion coefficient (ADC) values on magnetic resonance imaging (MRI) and to understand if it is possible to differentiate among pathological prostate tissues using ADC values.METHODS:Our population consisted in 81 patients (mean age 65.4 years) in which 84 suspicious areas were identified. Regions of interest were placed over suspicious areas, detected on MRI, and over areas with normal appearance, and ADC values were recorded. Statistical differences between ADC values of suspicious and normal areas were evaluated. Histopathological diagnosis, obtained from targeted biopsy using MRI-…

Diagnostic performance and reproducibility of T2w based and diffusion weighted imaging (DWI) based PI-RADSv2 lexicon descriptors for prostate MRI.

2017

To examine the diagnostic performance of PI-RADSv2 T2w and diffusion weighted imaging (DWI) based lexicon descriptors, inter-observer agreement for descriptor assignment and diagnostic accuracy of the PI-RADSv2 assessment categories for multiparametric prostate MRI.176 lesions in 79 consecutive patients are analyzed, lesions are histopathologically verified by MRI-ultrasound fusion biopsy. All lesions are rated according to the PI-RADSv2 lexicon, descriptors for T2w and DWI sequences and resulting assessment categories are assigned by two independent blinded radiologists. We perform receiver-operating-characteristic analysis using the assessment categories. To analyze inter-observer agreeme…

Neurochemical correlates of brain atrophy in fibromyalgia syndrome: a magnetic resonance spectroscopy and cortical thickness study

2020

(1) Background: Recently, a series of clinical neuroimaging studies on fibromyalgia (FM) have shown a reduction in cortical volume and abnormally high glutamate (Glu) and glutamate + glutamine (Glx) levels in regions associated with pain modulation. However, it remains unclear whether the volumetric decreases and increased Glu levels in FM are related each other. We hypothesized that higher Glu levels are related to decreases in cortical thickness (CT) and volume in FM patients. (2) Methods: Twelve females with FM and 12 matched healthy controls participated in a session of combined 3.0 Tesla structural magnetic resonance imaging (MRI) and single-voxel MR spectroscopy focused on the thalami…

Association of Dietary Patterns with MRI Markers of Hepatic Inflammation and Fibrosis in the MAST4HEALTH Study

2022

Whereas the etiology of non-alcoholic fatty liver disease (NAFLD) is complex, the role of nutrition as a causing and preventive factor is not fully explored. The aim of this study is to associate dietary patterns with magnetic resonance imaging (MRI) parameters in a European population (Greece, Italy, and Serbia) affected by NAFLD. For the first time, iron-corrected T1 (cT1), proton density fat fraction (PDFF), and the liver inflammation fibrosis score (LIF) were examined in relation to diet. A total of 97 obese patients with NAFLD from the MAST4HEALTH study were included in the analysis. A validated semi-quantitative food frequency questionnaire (FFQ) was used to assess the quality of diet…

Small solid renal masses: Characterization by diffusion-weighted MRI at 3 T

2013

AIM: To describe the appearance of small solid renal lesions (≤3 cm) on diffusion-weighted magnetic resonance imaging (MRI) and to determine whether ADC measurements may help to differentiate benign from malignant small solid renal masses. METHODS AND MATERIALS: Thirty-five patients with 47 small renal masses (23 malignant, 24 benign) who underwent 3 T MRI of the kidney using diffusion-weighted sequences (b values of 0 and 1000 s/mm(2)) were retrospectively evaluated. Qualitative and quantitative analysis of diffusion-weighted images was performed. RESULTS: Most lesions were hyperintense to kidney on high b-value diffusion-weighted images and hypointense on apparent diffusion coefficient (A…

Hepatocellular Carcinoma Presenting at Contrast-Enhanced Multi–Detector-Row Computed Tomography or Gadolinium-Enhanced Magnetic Resonance Imaging as …

2012

OBJECTIVE: The objective of the study was to measure growth rate and to determine the optimal interval time for imaging follow-up of hepatocellular carcinomas (HCCs) presenting at multi-detector-row computed tomography (MDCT) or magnetic resonance imaging (MRI) as small, indeterminate lesions. METHODS: We included patients with cirrhosis with HCC initially presenting as indeterminate lesion of 2 cm or less at MDCT or MRI August 2005 to August 2009 and with available imaging follow-up. Measures of tumor growth included tumor volume doubling time (TVDT), tumor percentual diameter increase, and tumor percentual volume increase. RESULTS: We examined 48 patients (mean age, 64 years) with 69 HCCs…

The Relevance of Noninvasive Tools To Assess Fibrosis in Non-Alcoholic Fatty Liver Disease.

2020

Non-alcoholic fatty liver disease (NAFLD) is a growing cause of chronic liver diseases worldwide, involving about 25% of people. NAFLD incorporates a large spectrum of pathological conditions, from simple steatosis to non-alcoholic steatohepatitis (NASH), cirrhosis and its complications include hepatic decompensation and hepatocellular carcinoma (HCC). This progression occurs, over many years, in an asymptomatic way, until advanced fibrosis appears. Thus, the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis are key issues. To date, the histological assessment of fibrosis with liver biopsy is the gold standard, but obviously, invasiveness is the …

Morphologic changes of the liver: how to recognize and analyze at CT and MRI

2008

MRI abnormalities following repeated and incoming seizures.

2010

Abstract Neuroimaging, an important diagnostic tool frequently used in the evaluation of patients with epilepsy, has mainly the aim to identify structural abnormalities needing a treatment and to contribute to the definition of the aetiology. Brain magnetic resonance imaging (MRI) in epilepsy is more sensitive than computerized tomography (CT) scan for detecting abnormalities. Status epilepticus (SE) and repeated incoming seizures may determine extensive and transient or long lasting pronounced MRI changes. We describe a case of a 41-year-old woman with a history of brain neoplasm, whose contrast-enhanced MRI images following repeated and incoming seizures were characterized either by rever…