Proton MR Spectroscopic and Diffusion Tensor Brain MR Imaging in X-linked Adrenoleukodystrophy: Initial Experience

Abstract

In patients with X-ALD, MR spectroscopic imaging can depict abnormalities in white matter that have a normal appearance on both conventional MR and DT images; this finding suggests that it may be the most sensitive technique for detecting early abnormalities of demyelination or axonal loss in patients with X-ALD.

Classification of Childhood White Matter Disorders Using Proton MR Spectroscopic Imaging

“…For example, in 3 patients with adrenoleukodystrophy, focal T2 signal-intensity abnormalities were limited to the posterior third of the centrum semiovale, with normal MR imaging signal intensity and metabolite ratios in the anterior and middle regions. Although abnormal spectra from normal-appearing white matter have been reported in some leukoencephalopathies, 14,15 it is possible that a study probing the region of greatest metabolic abnormality would have increased power for separating leukoencephalopathies of different etiologies.…”

Correlating Quantitative MR Imaging with Histopathology in X-Linked Adrenoleukodystrophy

“…Two multisection proton MRS imaging studies have reported similar abnormalities in white matter that has a normal appearance on conventional images in X-ALD. 25,26 The finding of a lower tNAA in NAWM indicates slight axonal damage, whereas the increases in concentrations of Cho, tCr, mIns, and Lac may represent slightly enhanced myelin turnover and astrocytic reaction, insufficient to lead to signal-intensity alterations on conventional MR imaging.…”

Advances in MR Imaging of Leukodystrophies

“…In X-ALD, a strong correlation exists between NAA levels and FA, reinforcing the concept that both reflect axonal integrity. However, proton MR spectroscopic imaging reveals a low NAA level in regions with normal MR and DT imaging findings (61). In contrast, DT imaging showed no abnormalities outside the lesion on T2-weighted images.…”