Search results for "Mri techniques"

MRI (Magnetic Resonance Imaging) in Psychiatry

2001

In recent years, structural and functional magnetic resonance imaging has opened up new avenues to the study of psychiatric disorders. A number of structural changes characteristic for different psychiatric diseases could be delineated by the use of magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) enables the in vivo investigation of cerebral neuronal activation under cognitive or behavioral activation paradigms. Magnetic resonance spectroscopy (MRS) allows for the study of defined neurochemical substances or pharmacological agents in the human brain. This article presents an overview of the basic principles of the different MRI techniques and representative re…

Comparative Analysis of Tagging and Feature-Tracking Cardiac MRI Techniques for the Evaluation of Cardiac Deformation

2020

[EN] Currently, there is a high prevalence of cardiovascular diseases, being the leading cause of mortality worldwide. Thus, a rapid and effective evaluation of the heart is increasingly relevant to diagnose the patient early and achieve appropriate treatment. For this reason, this study aims to compare myocardial deformation parameters such as circumferential strain (segmental, base, mid, apical and global) and global torsion values by the CMR tissue tagging reference technique in SPAMM cine images and the promising feature-tracking technique in b-SSFP cine images, in 31 healthy subjects and 35 patients diagnosed with infarct. The results obtained showed that there is a high agreement in t…

2020

(1) Background: Assessments of intervertebral disc (IVD) changes, and IVD tissue adaptations due to physical activity, for example, remains challenging. Newer magnetic resonance imaging techniques can quantify detailed features of the IVD, where T2-mapping and T2-weighted (T2w) and Dixon imaging are potential candidates. Yet, their relative utility has not been examined. The performances of these techniques were investigated to characterize IVD differences in asymptomatic individuals with distinct physical activity histories. (2) Methods: In total, 101 participants (54 women) aged 25–35 years with distinct physical activity histories but without histories of spinal disease were included. T1…

Assessment of chronic aortic dissection: contribution of different ECG-gated breath-hold MRI techniques.

2004

Our objective was to evaluate the impact of different rapid MRI techniques for the assessment and follow-up of chronic aortic dissections.Fifty-three patients (41 postoperative Stanford type A, 12 type B dissections) were scanned at 1.5 T during a 3-year period. The study reviewed ECG-gated breath-hold black blood sequences and 3D contrast-enhanced MR angiography of the thoracic aorta supplemented by segmented cine and phase-contrast imaging as well as abdominal contrast-enhanced MR angiography. A retrospective separate analysis of black blood acquisitions and contrast-enhanced MR angiograms from a total of 72 examinations was performed by two radiologists to evaluate detection of intimal f…

Orbital varices: a tricky diagnosis in MRI

1995

Orbital varix (OV) is a rare condition causing intermittent positional exophthalmos. Because of low venous pressure, OVs tend to collapse, being frequently undetectable in routine CT or MRI examinations. We describe one case of giant intraorbital varix studied with CT and MRI techniques.

Higher vascularity at infiltrated peripheral edema differentiates proneural glioblastoma subtype

2020

[EN] Background and purpose Genetic classifications are crucial for understanding the heterogeneity of glioblastoma. Recently, perfusion MRI techniques have demonstrated associations molecular alterations. In this work, we investigated whether perfusion markers within infiltrated peripheral edema were associated with proneural, mesenchymal, classical and neural subtypes. Materials and methods ONCOhabitats open web services were used to obtain the cerebral blood volume at the infiltrated peripheral edema for MRI studies of 50 glioblastoma patients from The Cancer Imaging Archive: TCGA-GBM. ANOVA and Kruskal-Wallis tests were carried out in order to assess the association between vascular fea…