Application of magnetic resonance images in patients with adrenoleukodystrophy

Objective To explore the role of proton MR spectroscopic imaging(1H-MRSI)and diffusion tensor imaging(DTI)in the diagnosis of adrenoleukodystrophy and to demonstrate the involvement of fibers by using the technique of DTT.Methods 1H-MRSI,DTI and routine imaging examinations were performed in 6 patients with ALD.The values of NAA,Cho,Cr,ADC,and FA were evaluated in different regions of lesion.The involved fibers were demonstrated by using the technique of DTT.Results The ratios of NAA/Cr(0.55±0.19)and NAA/Cho(0.22±0.11)were lower(F=7.693,7.751),and Cho/Cr(2.54±0.37)was higher(F=6.348)in the initial lesions,where higher ADC values(1.49±0.36,F=5.226)and the lowest FA values(0.21±0.08,F=5.139)were also observed(P＜0.05).The decreases of NAA/Cr(1.16±0.03)and NAA/Cho(0.45±0.17)in adjacent regions were more distinct than those of remote regions(t=1.769,1.842,P＜0.05).In the developing regions,the ADC values(0.89±0.03)were lower and the FA values(0.45±0.07)were the highest.There was negative correlation between NAA/Cho and ADC values(r=-0.71,P＜0.05),and there was positive correlation between NAA/Cho and FA values(r=0.31,P＜0.05).Discontinuations and fragments of fibres were observed in corpus callosum and pyramidal tract.Conclusions Combination of 1H-MRSI and DTI can offer a sensitive method for the early diagnosis and monitor the progress of white matter.DTT can be used to directly observe the involvement of fibers. Key words: Adrenoleukodystrophy;  Magnetic resonance spectroscopy; Diffusion magnetic resonance imaging