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ABSTRACT: We encountered a case showing a crazy-paving appearance on high-resolution computed tomography (HRCT), which mimicked various pulmonary diseases, e.g. pulmonary alveolar proteinosis, or non-specific interstitial pneumonia, but which we ultimately determined to be due to barium aspiration. The initial radiological findings were considered to be most likely due to pulmonary alveolar microlithiasis, because the crazy-paving appearance had high density, resembling calcification. However, distribution was limited to the area of dependent drainage of the right lung. Since a barium swallowing study had been performed 2 weeks before the CT examination, and since the follow-up HRCT showed improvement we reached a diagnosis of barium aspiration. Although barium aspiration may yield findings similar to other diseases with crazy-paving appearance, it is possible to identify it because of the limited distribution and high density.
Australasian Radiology 01/2008; 51 Suppl:B235-7. · 0.51 Impact Factor
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ABSTRACT: We measured the magnetisation transfer ratio (MTR) in the subcortical grey and white matter of 11 patients with idiopathic Parkinson's disease (PD) without dementia, six with PD with dementia (PDD), six with progressive supranuclear palsy (PSP), and 12 elderly control subjects to assess regional differences in structural brain damage. There were no significant differences in MTR in any region between PD and controls. However, patients with PDD had significantly lower MTR in the subcortical white matter, including the frontal white matter and the genu of the corpus callosum than the controls, whereas PSP had significantly lower MTR in the subcortical grey matter, including the putamen, globus pallidus and thalamus, in addition to the subcortical white matter. This suggests that regional patterns of structural brain damage can be detected using the magnetisation transfer technique. Measurement of MTR in the subcortical grey and white matter may be useful in differential diagnosis.
Neuroradiology 08/2001; 43(7):542-6. · 2.82 Impact Factor
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ABSTRACT: We measured magnetization transfer ratios (MTRs) of the hippocampus in 38 patients with Alzheimer's disease (AD), including very mild (Clinical Dementia Rating [CDR] 0.5, n=12), mild (CDR 1, n=14), and moderate stages (CDR 2, n=12), and in 21 healthy elderly control subjects. Medial temporal lobe atrophy was graded subjectively on a five-point scale by two observers blinded to clinical data. Compared with the controls, each of the AD groups, including the very mild group, had significant atrophy of the medial temporal lobe and a decrease in MTRs of the hippocampus. Logistic regression analysis revealed that the overall discrimination rate with MTR measurement and visual analysis of the atrophy was 85% and 73% between the control group and the CDR 0.5 group, 89% and 80% between the control group and the CDR 1 group, and 100% and 91% between the control group and the CDR 2 group, respectively. MTR measurements may provide additional information in detecting structural damage of the hippocampus of AD and be helpful in providing improved diagnosis and early detection of AD.
Journal of the Neurological Sciences 08/2001; 188(1-2):79-84. · 2.35 Impact Factor
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ABSTRACT: Although atrophy of structures in the medial temporal lobe has been considered an indication of Alzheimer's disease (AD), atrophic changes on MR images have also been associated with other dementing diseases and are not specific to AD. This study was undertaken to determine whether characteristic alterations in the hippocampus of patients with AD are detectable with magnetization transfer (MT) imaging.
Coronal MT imaging was performed in 35 patients with probable AD, in 14 patients with vascular dementia, in 13 patients with other types of dementia, and in 23 control subjects to measure MT ratios of the hippocampus. Medial temporal lobe atrophy was graded subjectively on a five-point scale.
Scores of medial temporal lobe atrophy in all dementia groups were significantly higher than those in control subjects, but no differences were found among the dementia groups. MT ratios in the hippocampus were significantly lower in patients with AD than in those with non-AD dementia and in the control subjects; however, no differences were found between the non-AD dementia patients and the control subjects. MT ratio measurements were better than visual analysis of atrophy for differentiating AD patients from those with non-AD dementia (an overall discrimination rate of 77% versus 65%). MT ratios significantly correlated with scores on the Mini-Mental State Examination and with medial temporal lobe atrophy in AD patients but not in patients with non-AD dementia.
MT measurements may be more specific than visual analysis in detecting structural damage of the hippocampus in AD patients and might be useful in discriminating AD from vascular dementia and other types of dementia.
American Journal of Neuroradiology 09/2000; 21(7):1235-42. · 2.93 Impact Factor
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ABSTRACT: We investigated structural changes of the corpus callosum in patients with Alzheimer's disease (AD) using sagittal diffusion-weighted (DW) and magnetization transfer (MT) imaging. Patients with AD (n=23) had a significantly decreased area only in the posterior portion of the corpus callosum. Apparent diffusion coefficient (ADC) values perpendicular to the commisural fiber orientation were significantly higher in the anterior portion of the corpus callosum without definite atrophy, as well as in the posterior portion with significant atrophy, in patients with AD than in controls (n=16) and thus diffusion in these regions showed a significantly lower degree of anisotropy in patients than in controls. MT ratios were also significantly lower in patients with AD in the anterior and posterior portions of the corpus callosum than in controls. These findings probably reflect structural changes in the corpus callosum including axonal loss and/or demyelination. DW and MT imagings may be useful in detecting degeneration of the corpus callosum in AD.
Journal of the Neurological Sciences 09/1999; 167(1):37-44. · 2.35 Impact Factor
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ABSTRACT: We measured the magnetization transfer (MT) ratios in white matter lesions of Binswanger's disease (BD) and compared them with BD and with similar-appearing changes in non-demented elderly subjects and cerebral infarction. Four subject groups were studied: 30 patients with BD and periventricular hyperintensity (PVH) on MRI, 29 patients with ischemic cerebrovascular event with PVH but no dementia, 17 patients with old cerebral infarction, and 26 elderly control subjects. MT ratios were calculated for areas of PVH in BD and non-demented subjects, of infarction, and of normal-appearing white matter in controls. The decrease in MT ratios for areas in PVH of non-demented subjects and BD and in infarction compared with normal white matter in controls was 12, 20, and 35%, respectively. The MT ratio in PVH of BD was significantly lower than that in PVH of non-demented subjects, but not to the levels seen in areas of infarction. There was a significant high correlation between the Mini-Mental State Examination score and MT ratio for area of PVH (r = 0.790). MT ratio distinguishes PVH in BD patients from those in non-demented subjects, suggesting underlying histopathological differences. Tissue damage in white matter lesions of BD may be more severe than that in non-demented subjects, but not as much as with complete infarction.
Journal of the Neurological Sciences 08/1999; 166(2):85-90. · 2.35 Impact Factor
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ABSTRACT: We investigated changes in water diffusion in the cerebral white matter of 14 patients with vascular dementia of the Binswanger type (VDBT) and ten patients with Alzheimer's disease (AD) with periventricular hyperintensity (PVH) lesions using diffusion-weighted magnetic resonance imaging (MRI) and studied the pathophysiological differences between white matter lesions found in these two conditions. Apparent diffusion coefficients (ADCs) in the anterior and posterior white matter and the genu and splenium of the corpus callosum were significantly higher in both groups of patients than in the 12 age-matched controls, and ADC values in VDBT and AD groups were almost the same. ADC ratios, defined as diffusion restricted perpendicular to the direction of nerve fibers, were also significantly higher in the patients than in the control subjects. However, there were regional differences in ADC ratios in the two conditions, with ratios in VDBT being higher in the anterior portions of the white matter but ratios in AD were higher in the posterior portions. The diffusion-weighted MRI technique may be useful in the differential diagnosis of VDBT and AD with white matter lesions.
European Journal of Neurology 04/1999; 6(2):195-203. · 3.69 Impact Factor
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ABSTRACT: We investigated the changes in water diffusion in the hippocampus and the temporal white matter (the temporal stem) in eight patients with possible Alzheimer's disease (AD), 10 patients with probable AD, and 10 age-matched controls, using coronal diffusion-weighted magnetic resonance (MR) imaging. Apparent diffusion coefficients (ADCs) were derived for the three orthogonal axes and an index of diffusion anisotropy (IDA = ADC(max-min)/ADC(mean)) was then calculated. Although no significant differences were found in ADC and IDA values in the hippocampal body between controls and patients, vertical (superior-inferior) ADC values and ADC(mean) values in the temporal stem of patients with AD were significantly higher than those in controls, and IDA values were therefore significantly lower in patients with possible or probable AD than those in controls. Moreover, IDA values in the temporal stem were significantly correlated with the clinical severity. These results suggest that decreased fiber density, such as the disruption and loss of axonal membranes or myelin, occur early in the temporal stem, probably due to secondary degeneration related to grey matter pathology including the medial temporal lobe.
Journal of the Neurological Sciences 05/1998; 156(2):195-200. · 2.35 Impact Factor
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ABSTRACT: We compared characteristic features in ischemic stroke lesions from the hyperacute to the chronic stage on diffusion-weighted (DW) and magnetization transfer (MT) images with those on T2-weighted (T2W) images, and assessed changes in apparent diffusion coefficient (ADC), MT effect (MTe), and T2 ratios (infarct/normal) over time. DW images were particularly useful for detecting hyperacute infarcts within 6 hours of onset and in distinguishing acute lesions from chronic lesions. ADC ratios were lower within 7 days after onset and rose toward 1.0 in the subacute phase, becoming relatively isotense on ADC maps, but elevated thereafter. Although MTe ratios were unchanged or only subtly changed in the acute stage, they became significantly lower in the subacute and chronic stages. These combined magnetic resonance (MR) techniques were useful in the assessment of ischemic stroke and facilitated the determination of the age of cerebral infarct.
Internal Medicine 05/1998; 37(4):360-5. · 0.94 Impact Factor
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ABSTRACT: Studies with single photon emission computed tomography (SPECT) have shown temporoparietal (TP) hypoperfusion in patients with Alzheimer's disease (AD). We evaluated the utility of this findings in the diagnosis of AD. SPECT images with 123I-iodoamphetamine were analyzed qualitatively by a rater without knowledge of the subject's clinical status. Sixty-seven of 302 consecutive patients were judged as having TP hypoperfusion by SPECT imaging. This perfusion pattern was observed in 44 of 51 patients with AD, in 5 with mixed dementia, 8 with cerebrovascular disease (including 5 with dementia), 4 with Parkinson's disease (including 2 with dementia), 1 with normal pressure hydrocephalus. 1 with slowly progressive aphasia. 1 with progressive autonomic failure, 2 with age associated memory impairment, and 1 with unclassified dementia. The sensitivity for AD was 86.3% (44 of 51 AD), and the specificity was 91.2% (229 of 251 non-AD). Next, we looked for differences in perfusion images between patients with AD and without AD. Some patients without AD had additional hypoperfusion beyond TP areas: deep gray matter hypoperfusion and diffuse frontal hypoperfusion, which could be used to differentiate them from the patients with AD. Other could not be distinguished from patients with AD by their perfusion pattern. Although patients with other cerebral disorders occasionally have TP hypoperfusion, this finding makes the diagnosis of AD very likely.
Nippon Ronen Igakkai Zasshi Japanese Journal of Geriatrics 07/1997; 34(6):468-73.
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ABSTRACT: To investigate age-related changes of diffusional anisotropy in the cerebral white matter, we performed diffusion-weighted MRI studies in 21 normal subjects aged 25 to 96 years. The anisotropic rations (ARs), defined as the apparent diffusion coefficients perpendicular to the nerve fibers to those parallel to the nerve fibers, were significantly higher in elderly than in young subjects in the anterior and posterior white matter surrounding the lateral ventricle. Moreover, significant correlation between age and AR was found in the anterior white matter. The ventricular index (VI) measured on MRI, as a quantitative indicator of brain atrophy, was significantly higher in elderly than younger subjects, and significantly correlated with AR in the anterior white matter. Multiple regression analysis demonstrated that the VI showed the highest correlation for AR. On the other hand, there was no significant correlations between ARs in the corpus callosum and age. These results suggest that morphological changes in the myelin and axon in the white matter occur in elderly normal subjects, probably due to neuronal loss with aging.
Nō to shinkei = Brain and nerve 05/1997; 49(4):331-6.
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ABSTRACT: We investigated the changes in water diffusion in the cerebral white matter in 19 patients with Alzheimer's disease (AD), including 11 without and 8 with periventricular hyperintensity (PVH) lesions, using diffusion-weighted magnetic resonance imaging (MRI). The apparent diffusion coefficients in the anterior and posterior white matter were significantly higher in the 19 AD patients than in the 10 age-matched controls. The apparent diffusion coefficients were higher in patients with PVH than in those without. The anisotropic ratios, defined as diffusion restricted perpendicular to the direction of the nerve fibers, were significantly higher in AD patients, even in those without PVH, than in the controls. Our results suggest that mild myelin loss occurs in AD patients even in the apparently normal white matter. A definite loss of myelin and axons, including incomplete infarction, occurs in the white matter, as seen on T2-weighted images as PVH. Studies with diffusion-weighted MRI may allow the characterization of different pathological processes and enable the demonstration of underlying white matter lesions in AD that cannot be visualized by conventional MRI.
Gerontology 02/1997; 43(6):343-51. · 2.78 Impact Factor
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ABSTRACT: We studied changes in water diffusion in cerebral white matter in 10 patients with Binswanger's disease (BD), 8 patients with Alzheimer's disease (AD) who had periventricular hyperintensity lesions on T2-weighted images, and 8 age-matched controls. The apparent diffusion coefficients measured in the anterior and posterior white matter were significantly higher in the patients than in the controls, but there was no significant difference between patients with BD and those with AD. The anisotropy ratios, difined as diffusion perpendicular to the nerve fiber direction, were higher in the patients than in the controls. The anisotropy ratio in the anterior white matter was significantly higher in patients with BD than in those with AD, while in the posterior white matter the ratio was significantly higher in patients with AD than in those with BD. These results suggest that in BD and AD cerebral white matter lesions such as periventricular hyperintensity lesions reflect a loss of myelin and axons, and that loss of myelin occurs preferentially in the anterior white matter in BD and in the posterior white matter in AD.
Nippon Ronen Igakkai Zasshi Japanese Journal of Geriatrics 11/1996; 33(10):761-7.
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ABSTRACT: To investigate changes in water diffusion in the cerebral white matter in Alzheimer-type dementia (AD), diffusion MRI studies were performed on 11 patients with AD without hyperintensity lesions on T2-weighted images, and 10 age-matched controls. In the anterior and posterior white matter around the lateral ventricule, and the splenium of the corpus callosum, the apparent diffusion coefficients (ADCs), in which the diffusion gradient was applied perpendicular to the predominant fiber direction, were significantly higher in patients with AD than in the controls. However, those in which the diffusion gradient was applied parallel to the predominant fiber direction, there were no significant difference in ADCs between patients and controls. Therefore, diffusional anisotropy was lost in the white matter. These results suggest that demyelination occurs in patients with AD even in apparently normal white matter (without signal abnormalitis). Degeneration related to grey matter encephalopathy may be a possible explanation of the demyelinating process in the white matter.
Rinsho shinkeigaku = Clinical neurology 08/1996; 36(7):909-11.
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ABSTRACT: We performed diffusion MRI studies in 14 patients with extensive ischemic leukoencephalopathy, including 9 with dementia (diagnosed as Binswanger's disease), and 5 without dementia, and 8 age-matched controls. Apparent diffusion coefficients (ADCs) in anterior and posterior periventricular white matter were significantly higher in demented and non-demented patients than in the controls, and diffusion anisotropy disappeared in patients because of the high ratio of the diffusion coefficients perpendicular to the nerve fibers to those parallel to the nerve fibers. ADCs in the corpus callosum were significantly higher in demented patients that in non-demented patients and controls. Therefore, diffusion anisotropy disappeared only in demented (Binswanger's disease) patients. These results suggest that the cerebral white matter lesions in Binswanger's disease reflect a decrease of nerve fibers and diffuse myelin loss, and that the loss of nerve fibers in the corpus callosum may play a role in inducing cognitive decline. Diffusion MRI may be useful in the pathophysiological evaluation of cerebral white matter lesions.
Rinsho shinkeigaku = Clinical neurology 04/1996; 36(3):442-50.
