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Background It is valuable to explore the relationship between plaque characteristics and stroke by using three-dimensional (3D) magnetic resonance imaging (MRI) of the vessel wall. Purpose To investigate the association between plaque enhancement score (PES) of co-existing intracranial and extracranial carotid plaques and ischemic stroke using 3D MRI. Material and Methods Symptomatic patients were recruited and underwent cerebrovascular 3D MRI of the vessel wall. The number, enhancement degree, and stenosis of plaques in intracranial and extracranial carotid arteries were evaluated. The PES calculated by summing enhancement degree of all detected plaques was compared between patients with and without acute cerebral infarction (ACI) and its association with ACI was determined. Results Of 157 recruited patients, 118 (75.2%) had co-existing plaques. Patients with ACI had significantly greater PES of co-existing plaques compared with those without ACI (9, interquartile range [IQR] 5–11 vs. 5, IQR 2–7, PConclusion Cerebrovascular plaque enhancement score combining plaque number and enhancement degree is independently associated with ACI. The enhancement score of co-existing plaques has higher strength in discriminating ACI compared with plaques in a single vascular bed.

Background Indirect traumatic optic neuropathy (ITON) is a devastating cause of permanent visual loss. Axonal degeneration, the characteristic pathological change of ITON, cannot be assessed by conventional imaging. Diffusion tensor imaging (DTI) has been widely used as a sensitive non-invasive imaging technique to obtain information on axonal integrity. Purpose To study time-dependent changes in ITON patients with DTI and to provide imaging evidence for clinical diagnosis and therapy. Material and Methods We enrolled 28 subjects with unilateral ITON who underwent detailed ocular examinations and magnetic resonance imaging (MRI) examinations. The differences between injured optic nerve (ON) and contralateral ON were tested. The patients were divided into three groups based on time (from injury to examination). Groups 1, 2, and 3 corresponded to the time taken from injury to examination: 30 days, respectively. DT magnetic resonance imaging (MRI) differences among the groups were compared, including the relationship between diffusion parameters and mean thicknesses of the peripapillary retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) in the macular area. Results Compared with contralateral ON, we observed reduced fractional anisotropy (FA) of injured nerves in group 2. Reduced FA and decreased axial diffusivity (λ//) and increased radial diffusivity (λ┴) and mean diffusivity (MD) of injured nerves were observed in group 3. The mean FA value of injured nerves showed a progressive decreasing trend, and mean λ┴ value exhibited a progressive increasing trend. For injured eyes, the MD and λ┴ increases strongly correlated with the decreased mean thicknesses of RNFL and GCC. Conversely, FA was significantly associated with mean RNFL thickness. Conclusion DT-MRI parameters could be useful biomarkers in detecting ON changes in ITON patients.

Background: Magnetic resonance spectroscopy (MRS) plays an important role in early diagnosis of Alzheimer disease (AD). There are many reports on MRS studies among individuals with AD and mild cognitive impairment (MCI). However, very few studies have compared spectroscopic data of different limbic regions among AD and MCI subjects. Purpose: To compare metabolite changes of different regions in the brain of AD and MCI patients by using 3.0T short-echo-time MRS. Material and Methods: Metabolite ratios in the hippocampus and posterior cingulate area were compared in a group of patients with AD ( n=16), MCI ( n=16), and normal subjects as a control group ( n=16). Clinical neuropsychological tests were measured in all subjects. Results: In the hippocampus, there were significant differences in N-acetylaspartate (NAA)/creatine (Cr), myo-inositol (mI)/Cr, and mI/NAA ratios among the three groups. However, there were no significant differences in choline (Cho)/Cr ratio among the three groups. In the posterior cingulate area, there were no significant differences in the NAA/Cr, Cho/Cr, and mI/Cr ratios among the three groups. However, there were significant differences in mI/NAA ratio between patients with AD and the control group, and between the AD and MCI groups. In addition, there was significant correlation between mI/NAA ratio and Mini Mental Status Exam (MMSE) score in subjects with AD and MCI. Conclusion: The study reveals that the elevation of mI/NAA ratio in the hippocampus is more significant than that in the posterior cingulate area, which corresponds to the pathologic procession of AD. The ratios of mI/NAA in the hippocampus and in the posterior cingulate area together provide valuable discrimination among the three groups (AD, MCI, and controls). There is a significant correlation between mI/NAA ratio and cognitive decline.