Other White Matter Diseases

Super Memory Formula

Effective Diet for Memory Loss

Get Instant Access

The use of MR systems at 3.0 T or higher is relatively new and although several studies have already been conducted on MS, the literature on the use of higher field MR scanners for the study of other white matter diseases is still scarce. Table 15.1 summarizes some of the recent work that has been done so far to assess white matter damage in diseases such as frontotempo-ral dementia [28], aging [22, 41], Alzheimer's disease [21], and adrenoleukodystrophy [38] with 3.0 or 4.0 T MR scanners. The assessment of white matter changes in neurodegenerative conditions is likely to bring insights into the understanding of white matter diseases where the presence of a neurodegenerative component is increasingly being accepted. Admittedly, normal aging is not a disease; however, again work done with 'H-MRS at 4.0 T [22] and DT MRI at 3.0 T [41] might ultimately help understand some of the processes occurring in the pathological brain.

During the past few years, the application of advanced MR techniques for the assessment of patients with migraine has shown that, similarly to what has been described in other chronic vascular affections, including leukoaraiosis, cerebral autosomal dominant ar-teriopathy with subcortical infarcts and leukoencepha-lopathy (CADASIL), brain damage extends beyond the resolution of conventional imaging and diffusely involves the normal-appearing brain tissue (NABT). In a preliminary study using *H-MRS at 3.0 T, we found that NAA is reduced in white matter lesions as well as in the NAWM of patients with migraine (Fig. 15.3). Concentrations of choline follow an opposite trend, with increased concentrations in the NAWM and lesions. Preliminary findings obtained with DT MRI at 3.0 T also suggest the presence of occult damage in the NABT of patients suffering from migraine.

Table 15.1. Summary of some of the recent work done so far to assess white matter damage in diseases such as frontotemporal dementia, aging, Alzheimer's disease, and adrenoleukodystrophy with 3.0 or 4.0 T MR scanners

Author, year

Disease

Technique

Field strength

Subjects

Findings

Hattori et al., AD 2002 [21]

1H-MRS

3.0 T

9P, 12C

In patients, the N-acetyl group (NA)/creatine + phosphocreatine (Cr) ratios were decreased in both the GM of the posterior cingu-late gyrus and the precuneus, and the parieto-occipital WM regions. A decrease in the glutamate + glutamine (Glx)/Cr ratio and a correlation between the NA/Cr and Glx/Cr ratios were detected in the GM, but not in the WM. NA and Glx metabolism are simultaneously affected in AD; however, metabolic changes in Glx are more profound in the GM than in the WM

Oz et al., 2005 [38]

ALD

1H-MRS

4.0 T

17P, 26C

Detection of early neurochemical changes in lesion formation prior to detection of abnormalities by conventional MRI. Creatine and choline containing compounds were the weakest markers of cerebral disease while N-acetylaspartate, glutamine, and lipids + lactate were the strongest

Larsson et al., 2004 [28]

FTD

CMRI, DTI

3.0 T

1P (p-m)

In this postmortem investigation of brain tissue by MRI, DTI and histopathology, frontotemporal atrophy as well as bilateral frontal WM abnormalities were seen. The WM changes were slightly more extensive on DTI than on conventional MRI. Correlation with histopathology of the corresponding regions revealed typical frontal lobe degeneration of non-Alzheimer type, with mild fron-totemporal degeneration in the outer cortical layers and a moderate frontal WM gliosis with demyelination

Kaiser et al., 2005 [22]

Normal aging

1H-MRS

4.0 T

24C

Comparisons between old and young subjects showed higher concentration of scyllo-inositol and myo-inositol in older subjects and a trend for a correlation between scyllo-inositol and myo-inositol levels across subjects

Pfefferbaum et al., 2005 [41]

Normal aging

DTI

3.0 T

20C

Selective decline in frontal WM anisotropy and high bulk mean diffusivity in healthy older compared with younger adults. However, posterior systems are largely preserved with age. The study highlights the potential implication of a microstructural WM mechanism for the commonly observed decline in frontally based functions

AD Alzheimer's disease, ALD adrenoleukodystrophy, FTD frontotemporal dementia, DTI diffusion tensor imaging, MRS magnetic resonance spectroscopy, CMRI conventional MRI, P patients, C controls, p-m postmortem, GM grey matter, WM white matter

AD Alzheimer's disease, ALD adrenoleukodystrophy, FTD frontotemporal dementia, DTI diffusion tensor imaging, MRS magnetic resonance spectroscopy, CMRI conventional MRI, P patients, C controls, p-m postmortem, GM grey matter, WM white matter

Was this article helpful?

0 0
Unraveling Alzheimers Disease

Unraveling Alzheimers Disease

I leave absolutely nothing out! Everything that I learned about Alzheimer’s I share with you. This is the most comprehensive report on Alzheimer’s you will ever read. No stone is left unturned in this comprehensive report.

Get My Free Ebook


Post a comment