Magnetic resonance imaging (MRI) is the diagnostic tool that currently offers the most sensitive and non-invasive way to obtain images of the brain, spinal cord, or other areas of the body. It is the preferred imaging method to help establish a diagnosis of MS and monitor the course of the disease. Multiple sclerosis (MS) is an autoimmune disease that alters CNS neurotransmission. Intensive focal demyelination and white matter infiltration by lymphocytes and mononuclear cells are pathological features of the disease.
In the absence of therapy, repeated attacks lead to an accumulation of lesions in MS, which is manifested as physical and cognitive impairment. Multiple sclerosis studies require sensitive and reliable imaging methods to investigate specific pathological changes in white matter during disease progression. Magnetic resonance imaging is currently the most used technique for the diagnosis of MS. In conventional magnetic resonance imaging, T1-weighted serial images detect chronic neurodegeneration, with improved contrast with gadolinium, showing not only the migration of immune cells across the blood-brain barrier, but also active inflammation in lesions.
T2-weighted serial images are more widely used to identify the number and volume of clinically silent lesions. These MRI acquisition techniques have greatly facilitated the clinical observation and understanding of MS, and diagnostic criteria based on MRI findings have been proposed. However, conventional magnetic resonance imaging shows insufficient sensitivity and specificity to indicate the extent and severity of very diverse MS lesions. The correlation between the quantification of lesions using magnetic resonance imaging and functional disabilities assessed using clinical measures is also poor.
The correlation between ventricular diameter measured by transcranial ultrasonography and clinical disability and cognitive dysfunction in patients with multiple sclerosis. Unfortunately, the application of most of the above techniques on a single-topic basis lacks viability until further research is done with large, well-designed studies using standardized acquisition techniques and automated analysis methods (Martin et al. For a more sensitive and robust detection of CVS, optimized techniques based on susceptibility can be used instead. Typical lesions of the white matter and gray matter of multiple sclerosis (MS) in the brain, as shown by 3T brain magnetic resonance imaging (MRI).
One such technique is susceptibility weighted imaging (SWI), which was initially developed to perform brain venograms. NMR techniques, including MRI, exploit the resonance and relaxation properties of protons in nuclei that have an odd number of nucleons. Therefore, complete brain NAA measured by MRS appears to be a more sensitive neuroimaging marker of disease progression. Unfortunately, the practical clinical use of these advanced magnetic resonance techniques remains limited due to the variability in the availability of hardware, scanning protocols, and other technical variables between institutions.
First, the ability to image myelin without labels is particularly important for in vivo studies where labeling is complicated by inefficient diffusion and non-specific binding in the tissue environment. Over the past decade, many other nuclear magnetic resonance (NMR) techniques have been developed or exploited to improve sensitivity and specificity in the detection of MS lesions. See Multiple Sclerosis, a slideshow of critical images, for more information on the incidence, presentation, intervention, and additional resources. A, Enlarged portion of a T2*-weighted axial image of a multiple sclerosis (MS) patient (in-plane resolution of 195 × 260 μm) acquired at 7.0 T and revealing the fine details of a putative intracortical demyelinating lesion (yellow arrow).
N-acetylaspartate (NAA) is a relatively specific neuronal marker that is present in sufficient concentrations in the brain to be revealed in MR spectroscopic images. Conventional imaging techniques, including double-echo, FLAIR and GD sequences, play a critical role in diagnosing patients with CIS, while in patients with established MS they provide poor prognostic information. Based on the successful measurement of NAA, choline and myoinositol with proton MRS, it has become desirable to add this imaging technique to the clinical diagnostic battery. .
