Search results for "Resonance"

Neuropathology of Cerebellar Infarction: Its Morphology in Comparison to Selective Postmortem Angiography of Cerebellar Arteries

1994

A typology of infarctions [11, 20] is established for the cerebral hemispheres and has recently also been used, chiefly in neuroradiological diagnosis, for cerebellar infarctions [2–5, 8, 10, 16]. Detailed clinical [12] and microangiographic [7, 9, 13, 15, 17] investigations of the vascularization of the posterior cranial fossa can be referred to in this context. With the aid of selective postmortem angiograms we examined the territories of the superior cerebellar artery (SCA), anterior inferior cerebellar artery (AICA), and posterior inferior cerebellar artery (PICA) on serial sections in the three planes of projection. The sagittal plane offers decisive advantages for assigning cerebellar…

Complete biochemical control and pituitary adenoma disappearance in a child with gigantism: Efficacy of octreotide therapy

2011

Resting myocardial blood flow quantification using contrast-enhanced magnetic resonance imaging in the presence of stenosis: A computational fluid dy…

2015

Purpose: The extent to which atherosclerotic plaques affect contrast agent (CA) transport in the coronary arteries and, hence, quantification of myocardial blood flow (MBF) using magnetic resonance imaging (MRI) is unclear. The purpose of this work was to evaluate the influence of plaque induced stenosis both on CA transport and on the accuracy of MBF quantification. Methods: Computational fluid dynamics simulations in a high-detailed realistic vascular model were employed to investigate CA bolus transport in the coronary arteries. The impact of atherosclerosis was analyzed by inserting various medium- to high-grade stenoses in the vascular model. The influence of stenosis morphology was ex…

AB0630 Cardiac Magnetic Resonance Imaging with Pharmacological Stress Perfusion in Asymptomatic Patients with Systemic Sclerosis

2016

Background Systemic Sclerosis (SSc)-heart disease (SSc-HD), although often clinically silent, significantly reduces the life-expectancy in these patients [1]. The cardiac magnetic resonance (CMR) is recognized useful tool for the diagnosis of SSc-HD and cardiac stress tests might be a helpful technique to highlight the occult myocardial involvement, which cannot be detected at rest due to compensatory mechanisms [2,3]. Objectives To evaluate the possible occult cardiac involvement in asymptomatic SSc patients by pharmacological stress, rest perfusion and delayed enhancement CMR, to identify as earlier as possible those patients at higher risk of cardiac related mortality and needing specifi…

Cerebrovascular Brainstem Diseases with Isolated Cranial Nerve Palsies

2002

There is a significant number of individual patients with cranial nerve palsies as the sole manifestation of MRI- and, less frequently, CT-documented small brainstem infarctions or hemorrhages. The 3rd and 6th nerves are most commonly involved and, less frequently, the 4th, 5th, 7th, and 8th nerves. An intra-axial basis for such lesions may be underestimated if the diagnosis is based solely on MRI. The electrophysiologic abnormalities indicating brainstem lesions may be independent of MRI-documented morphological lesions. This paper reviews the literature on cerebrovascular brainstem diseases manifesting as isolated cranial nerve palsies. It supports the concept that small pontine and mesen…

Third nerve palsy as the sole manifestation of midbrain ischemia

1995

Thirty-seven patients with risk factors for the development of cerebrovascular diseases had sudden onset isolated third nerve palsy and abnormal masseter reflex and/or electro-oculographic findings indicating a causative midbrain lesion. Improvement or recovery of the third nerve palsies was accompanied by improvement or recovery of the abnormal electrophysiologic findings pointing to their functional significance. Magnetic resonance imaging (MRI) in 29 of these patients demonstrated corresponding ischemic midbrain lesions in eight, ipsilateral in five patients, bilateral in three. In another three patients with MRI proven midbrain lesions (ipsilateral in two, bilateral in one) electrophysi…

Focal liver lesions hyperintense on T1-weighted magnetic resonance images.

2009

This article reviews focal liver lesions hyperintense on T1-weighted magnetic resonance (MR) images and describes the underlying etiologies associated with their T1 signal intensity. Although focal liver lesions are commonly detected because of their iso- or hypointensity on T1-weighted images, lesions (benign or malignant) may present with T1 hyperintensity when they contain T1 shortening elements--such as fat, hemorrhage, copper, melanin, and highly concentrated proteins. Our discussion includes the description of state-of-the-art T1-weighted MR sequences and the imaging features of lesions on pre- and postcontrast MR images that are characteristic for lesion composition and useful for ma…

Liver intravoxel incoherent motion (IVIM) magnetic resonance imaging: a comprehensive review of published data on normal values and applications for …

2017

A comprehensive literature review was performed on liver intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) technique and its applications. Heterogeneous data have been reported. IVIM parameters are magnetic field strength dependent to a mild extent. A lower Dslow (D) value at 3 T than at 1.5 T and higher perfusion fraction (PF) value at 3 T than at 1.5 T were noted. An increased number of b values are associated with increased IVIM parameter measurement accuracy. With the current status of art, IVIM technique is not yet capable of detecting early stage liver fibrosis and diagnosing liver fibrosis grades, nor can it differentiate liver tumors. Though IVIM parameters show p…

Lung ventilation- and perfusion-weighted Fourier decomposition magnetic resonance imaging: In vivo validation with hyperpolarized3He and dynamic cont…

2012

The purpose of this work was to validate ventilation-weighted (VW) and perfusion-weighted (QW) Fourier decomposition (FD) magnetic resonance imaging (MRI) with hyperpolarized (3)He MRI and dynamic contrast-enhanced perfusion (DCE) MRI in a controlled animal experiment. Three healthy pigs were studied on 1.5-T MR scanner. For FD MRI, the VW and QW images were obtained by postprocessing of time-resolved lung image sets. DCE acquisitions were performed immediately after contrast agent injection. (3)He MRI data were acquired following the administration of hyperpolarized helium and nitrogen mixture. After baseline MR scans, pulmonary embolism was artificially produced. FD MRI and DCE MRI perfus…

Delayed MRI Hyperenhancement in Noncompaction: Sign of Fibrosis Correlated with Clinical Severity

2008

N.A.