In Vivo Assessment of Neurodegeneration in Type C Niemann-Pick Disease by IDEAL-IQ

OBJECTIVE: To noninvasively assess the neurodegenerative changes in the brain of patients with Niemann-Pick type C (NPC) disease by measuring the lesion tissue with the iterative decomposition of water and fat with echo asymmetry and least square estimation-iron quantification (IDEAL-IQ). MATERIALS AND METHODS: Routine brain MRI, IDEAL-IQ and 1H-proton magnetic resonance spectroscopy (1H-MRS, served as control) were performed on 12 patients with type C Niemann-Pick disease (4 males and 8 females; age range, 15–61 years; mean age, 36 years) and 20 healthy subjects (10 males and 10 females; age range, 20–65 years; mean age, 38 years). The regions with lesion and the normal appearing regions (NARs) of patients were measured and analyzed based on the fat/water signal intensity on IDEAL-IQ and the lipid peak on 1H-MRS. RESULTS: Niemann-Pick type C patients showed a higher fat/water signal intensity ratio with IDEAL-IQ on T2 hyperintensity lesions and NARs (3.7–4.9%, p < 0.05 and 1.8–3.0%, p < 0.05, respectively), as compared to healthy controls (HCs) (1.2–2.3%). After treatment, the fat/water signal intensity ratio decreased (2.2–3.4%), but remained higher than in the HCs (p < 0.05). The results of the 1H-MRS measurements showed increased lipid peaks in the same lesion regions, and the micro-lipid storage disorder of NARs in NPC patients was detectable by IDEAL-IQ instead of 1H-MRS. CONCLUSION: The findings of this study suggested that IDEAL-IQ may be useful as a noninvasive and objective method in the evaluation of patients with NPC; additionally, IDEAL-IQ can be used to quantitatively measure the brain parenchymal adipose content and monitor patient follow-up after treatment of NPC.

Diffusion tensor imaging of the brain in patients with Alzheimer's disease and cerebrovascular lesions / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>BACKGROUND</b>Recent autopsy study showed a high incidence of cerebrovascular lesions in Alzheimer's disease (AD). To assess the impact of cerebrovascular pathology in AD, we used diffusion tensor imaging (DTI) to study AD patients with and without cerebrovascular lesions.</p><p><b>MATERIALS AND METHODS</b>Conventional and DTI scans were obtained from 10 patients with probable AD, 10 AD/V patients (probable AD with cerebrovascular lesions) and ten normal controls. Mean diffusivity (D) and fractional anisotropy (FA) values of some structures involved with AD pathology were measured.</p><p><b>RESULTS</b>D value was higher in AD patients than in controls in hippocampus and the cingulate gyrus. In AD/V patients, increased D value was found in the same structures and also in the thalamus and basal ganglia compared to controls. There was a significant difference of D value between AD and AD/V patients. FA value reduced in the white matter of left inferior temporal gyrus and in the bilateral middle cingulate gyrus in patients with AD/V compared with controls. The MMSE (mini-mental state examination) score significantly correlated with FA value in the right hippocampus (r=0.639, P<0.019), in the right anterior cingulate gyrus (r=0.587, P<0.035) and in left parahippocampal gyrus (r=0.559, P<0.047).</p><p><b>CONCLUSION</b>Cerebrovascular pathology had stronger impact on the D value than the AD pathology alone did. Elevated D value in thalamic and basal ganglia may contribute to cognitive decline in AD/V patients. Reduced FA values in AD/V patients may indicate that cerebrovascular pathology induced more severe white matter damage than the AD pathology alone did.</p>

Diffusion tensor imaging and three-dimensional brain fiber tracking for the diagnosis of multiple sclerosis / 中华放射学杂志

Objective To demonstrate the diffusion tensor imaging(DTI)characteristics of multiple sclerosis(MS)plaques,periplaque white matter regions and normal appearing white matter (NAWM)regions in patients with MS,and to evaluate the clinical values of DTI and three-dimensional brain fiber tracking for the diagnosis of MS.Methods Conventional MRI and DTI were performed in 32 patients with MS and 32 age-matched control subjects.Fractional anisotropy(FA)and apparent diffusion coefficient(ADC)maps were generated and coregistered with T_2-weighted MR images,FA and ADC values were calculated in regions of interest in plaques,periplaque white matter regions,NAWM regions and white matter regions in control subjects.And three-dimensional brain fiber tracking maps were generated by using the DTI.Results TheADCwas(1.233?0.119)?10~(-3)mm~2/s in MS plaques,(0.973?0.098)?10~(-3) mm~2/s in periplaque white matter regions,(0.748?0.089)?10~(-3)mm~2/s in NAWM,and(0.620? 0.094)?10~(-3)mm~2/s in control subjects.The FA was 0.225?0.052 in MS plaques,0.311?0.050 in perip]aque white matter regions,0.421?0.070 in NAWM,and 0.476?0.069 in control subjects. Significant differences in FA and ADC values were observed among all white matter regions(P