American Journal of Neuroradiology 24:1683-1689, September 2003
© 2003 American Society of Neuroradiology
PEDIATRICS
Proton MR Spectroscopic Imaging in Pelizaeus-Merzbacher Disease
a Kennedy Krieger Institute
b Department of Radiology, the Johns Hopkins University School of Medicine, Baltimore, MD
c Department of Neurology, the Johns Hopkins University School of Medicine, Baltimore, MD
Address reprint requests to Peter B. Barker, DPhil, Department of Radiology, MR Imaging 143C, the Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD 21287
BACKGROUND AND PURPOSE: Pelizeaus-Merzbacher disease (PMD) is a clinically and molecularly heterogeneous disorder linked to deletion, mutations, or duplication of the proteolipid protein (PLP1) gene locus at Xq22. The current study was conducted to characterize the results of proton MR spectroscopic (MRS) imaging in PMD.
METHODS: Three boys with PMD (one with the severe connatal form and two with a more mild clinical phenotype [spastic paraplegia type 2]). and three age-matched healthy control subjects (age range, 2–7 years) underwent MR and MRS imaging . All imaging was performed at 1.5 T. For MRS imaging, oblique-axial sections (thickness, 15 mm; intersection gap, 2.5 mm) were recorded parallel to the anterior commissure–posterior commissure line (TR/TE/NEX, 2300/272/1) with lipid and water suppression. Ratios of metabolite peak areas were calculated, and spectra were bilaterally evaluated.
RESULTS: Diffuse or focal reductions in N-acetylaspartate were observed in the affected white matter in all three cases. These reductions seemed to be consistent with axonal damage. In addition, mild increases in choline and creatine levels were observed; these may have been due to astrocytic changes.
CONCLUSION: Proton MRS imaging may be helpful in evaluating regional pathophysiologic abnormalities in PMD and in distinguishing PMD from other leukodystrophies, which exhibit different metabolic profiles.