Multipe Sclerosis - Diagnosis

MRI - updated: 10 November 2009

Magnetic resonance techniques to quantify tissue damage, tissue repair, and functional cortical reorganization in multiple sc

Prog Brain Res. 2009;175:465-82.

Filippi M, Agosta F.

A dramatic paradigm shift is taking place in our understanding of the pathophysiology of multiple sclerosis (MS). An important contribution to such a shift has been made possible by the advances in magnetic resonance imaging (MRI) technology, which allows structural damage to be quantified in the brains of patients with MS and to be followed over the course of the disease. Modern quantitative MR techniques have reshaped the picture of MS, leading to the definition of the so- called "axonal hypothesis" (i.e., changes in axonal metabolism, morphology, or density are important determinants of functional impairment in MS). Metrics derived from magnetization transfer and diffusion-weighted MRI enable us to quantify the extent of structural changes occurring within T2-visible lesions and normal-appearing tissues (including gray matter), with increased pathological specificity over conventional MRI to irreversible tissue damage; proton MR spectroscopy adds valuable pieces of information on the biochemical nature of such changes. Finally, functional MRI can provide new insights into the role of cortical adaptive changes in limiting the clinical consequences of MS-related irreversible structural damage. Our current understanding of the pathophysiology of MS is that this is not only a disease of the white matter, characterized by focal inflammatory lesions, but also a disease involving more subtle and diffuse damage throughout the white and gray matter. The inflammatory and neurodegenerative components of the disease process are present from the earliest observable phases of the disease, but appear to be, at least partially, dissociated. In addition, recovery and repair play an important role in the genesis of the clinical manifestations of the disease, involving both structural changes and plastic reorganization of the cortex. This new picture of MS has important implications in the context of treatment options, since it suggests that agents that protect against neurodegeneration or promote tissue repair may have an important role to play alongside agents acting on the inflammatory component of the disease.

Publication Types:

• Review

Diffusion tensor MR imaging

Neuroimaging Clin N Am. 2009 Feb;19(1):37-43.

Rovaris M, Agosta F, Pagani E, Filippi M.

Diffusion tensor (DT) MR imaging is able to detect and quantify multiple sclerosis (MS)-related tissue damage within and outside T2-visible lesions. DT MR imaging has also been shown to be sensitive to the evolution of MS damage over time and to provide in vivo correlates of MS clinical severity and paraclinical markers of long-term disease evolution. Recent developments of DT MR imaging postprocessing techniques, such as tractography and voxelwise analysis, are likely to improve our understanding of the mechanisms associated with the accumulation of disability in MS. Important issues remain to be addressed, such as a detailed definition of the actual features underlying diffusion changes in MS and the potential of the technique in the differential diagnosis of MS.

Publication Types:

• Review

The importance of early diagnosis of multiple sclerosis

J Manag Care Pharm. 2004 Jun;10(3 Suppl B):S4-11.

Miller JR.

OBJECTIVE: To describe the current understanding of the diagnosis and treatment of multiple sclerosis (MS) and to explore the use of magnetic resonance imaging (MRI) assessment as a prognostic tool and an indicator in the diagnosis of MS. SUMMARY: MS is a chronic, progressive, demyelinating disease of the central nervous system that is associated with a significant economic burden. At this time, immunomodulatory agents (interferon beta-1a (IFNbeta-1a) [Avonex], IFNbeta-1a [Rebif], IFNbeta-1b [Betaseron], and glatiramer acetate [Copaxone]) are first-line agents, which are reported to reduce relapse rates. The diagnostic criteria for MS have evolved over time to include MRI findings as an integral part of the diagnosis. However, the most recent criteria (McDonald) are focused on the diagnosis of definite MS and do not address the status of patients with a first demyelinating event (clinically isolated syndrome [CIS]). This is an important issue because a CIS is highly predictive of developing further inflammation and definite MS when the episode occurs in conjunction with lesions on the initial MRI. Many times, MRI findings do not correlate with clinical symptoms, and clinically silent lesions are identified. Therefore, the use of MRI is salient to the early diagnosis of high-risk patients. The evolution of thought concerning early treatment in MS is based on an increased understanding of the pathology of the disease. Axonal loss occurs early in the disease process, and both white matter and gray matter are affected. Studies that have analyzed early treatment in patients highly likely to have MS (clinically isolated events with evidence of lesions on MRI) report significant benefits in delaying further changes on MRI and further attacks. Patients who begin treatment later do not reap the same benefits as those who begin treatment earlier during the disease course. CONCLUSION: Patients with clinically isolated events should be referred promptly to a neurologist for assessment, including MRI scans. An early recognition of the inflammatory process enables patients to begin treatment with an immunomodulatory agent even before the technical diagnosis of definite MS so that the degenerative progression of MS can be retarded.

Publication Types:

• Review

Publication Types:

• Review