European journal of radiology
-
Diffusion-weighted sequence (DWI) of the entire body is a new promising technique feasible to evaluate multifocal disease. DWI has revealed great potential in the evaluation of patients with cancer or benign disease, as it supplies both quantitative and qualitative information of the whole body. ⋯ A complete whole-body MR imaging protocol including the DWI can be performed in less than 40 min. The possibilities, limitations and the preliminary clinical results of the whole-body MR imaging using a DWI of the entire body are reviewed.
-
Functional magnetic resonance imaging technique is a non-invasive tool that is capable to detect the subtle hemodynamic changes produced during regional brain activation. Functional MRI applications in epilepsy patients are language lateralization and mapping, memory function assessment and localization of ictal and interictal changes. ⋯ A new application is ictal or interictal functional MRI with EEG recording that provides more detailed information about simultaneous electrographic and hemodynamic changes during interictal discharges or EEG seizures. This technique seems to have encouraging results to localize the epileptogenic area and to study propagation patterns.
-
Since its approval by the FDA in 2000, brain MR imaging at 3.0 T has been increasingly used in clinical practice. Theoretically, the signal-to-noise ratio (SNR) of a 3T MR scanner will be double that of a 1.5 T scanner. ⋯ Today, using a 3T magnet in Neuroradiology has far more advantages than disadvantages, and the diagnostic potential of higher strength magnets for structural and vascular scans, diffusion and perfusion imaging, spectroscopy and cortical activation studies is improving. However, it is useful to have an awareness of how increasing field strength affects each of these techniques so that full advantage may be taken of them.
-
Controlled Clinical Trial
Pharmacokinetic MR analysis of the cartilage is influenced by field strength.
To study if the pharmacokinetic parameters derived from dynamic contrast-enhanced magnetic resonance (DCE-MR) images of the patellar cartilage are influenced by the main magnetic field strength. ⋯ Cartilage vascular permeability values are influenced by the MR field strength. This should be taken in consideration when analyzing this biomarker.
-
Multiple sclerosis is a chronic, persistent inflammatory-demyelinating disease of the central nervous system that typically presents as an acute clinically isolated syndrome attributable to a monofocal or multifocal demyelinating lesion, which usually affects the optic nerve, spinal cord, or brainstem and cerebellum. Although the diagnosis of multiple sclerosis is still based on clinical findings, magnetic resonance imaging is now integrated in the overall diagnostic scheme of the disease because of its unique sensitivity to demonstrate the spatial and temporal dissemination of demyelinating plaques in the brain and spinal cord. Conventional magnetic resonance imaging techniques, such as T2-weighted and gadolinium-enhanced T1-weighted sequences are highly sensitive in detecting multiple sclerosis plaques and provide a quantitative assessment of inflammatory activity and lesion load. ⋯ In recent years, great effort has been dedicated to overcoming these limitations by using non-conventional magnetic resonance-derived metrics that can selectively measure the more destructive aspects of multiple sclerosis pathology and monitor the reparative mechanisms. These metrics, which include unenhanced T1-weighted imaging, measures of central nervous system atrophy, magnetization transfer imaging, proton magnetic resonance spectroscopy, diffusion-weighted imaging, and functional magnetic resonance imaging, provide a better approximation of the pathological substrate of the multiple sclerosis plaques, have increased our understanding of the pathogenesis of the disease, and have proven useful for studying the natural history of multiple sclerosis and monitoring the effects of new treatments. Therefore, magnetic resonance imaging not only plays an essential role in the diagnosis of multiple sclerosis, but can also serve as a true biological marker of the severity of this disease.