Eight patients suffering from senile dementia were treated utilizing a series of computerized visual recognition training tasks. The training tasks included one each dynamic and static procedures. The dynamic task was to recognize and pursue a smoothly moving target among several obstacle characters, and the static task was to recognize a specific alphabetic letter among many letters. One training set took about 25-30 minutes, and three sets were done per week for four weeks. After the training period was over, the response time required to recognize the moving target (dynamic task) and a specific letter (static task) was shortened significantly. The right answer rate increased as well. Moreover, the subjects' performance on cognition testing (mini-mental state examination) improved after the four-week rehabilitation training. These results suggest that patients with senile dementia may benefit from this kind of visual recognition training, and the probable mechanism may lie in the reactivity of the brain under cognitive visual stimulation.

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The purpose of this study was to develop an algorithm that can be used to distinguish the central part of the vertebral body in an abdominal X-ray CT image, and to use that algorithm to automatically calculate three measures that are used to diagnose osteoporosis. In addition, the correlation between the BMD (bone mineral density) and these measures was investigated. We also examined whether the CT images obtained could be used to aid in diagnosing osteoporosis. The abdominal region contained in the third lumbar vertebra was scanned using spiral CT equipment (CT-W950SR: Hitachi). We judged whether female patients had osteoporosis using the diagnostic criteria available (Year 2000 revision, published by the Japanese Society for Bone and Mineral Research: only female data available). Twenty-two female patients, with an age range of 35-79 years (average age: 61.8), were examined. The mean CT number, coefficient of variation, and the first moment of the power spectrum were calculated as measures representing specific features of osteoporosis disease in the recognized vertebral body. We classified three measures obtained from the CT images for normal and abnormal groups using discriminant analysis, and the results obtained from the diagnosis criteria for the two groups were then compared. Our results showed that the algorithm could be used to distinguish the central part of the vertebral body in all cases, and to calculate these measures automatically. When the results of the discriminant analysis were applied to the three measures obtained from the CT images, the ratio usable for diagnosing a patient as osteoporotic (sensitivity) was 0.79 (11/14), and the ratio usable for diagnosing a patient as normal (specificity) was 0.63 (5/8). Therefore, in conclusion, we believe that this algorithm can be used to aid physicians in diagnosing osteoporosis, utilizing the measures obtained from abdominal X-ray CT images.

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Through event related functional magnetic resonance imaging (fMRI), brain activity was mapped in three normal subjects while they imagined grasping a softball with their own hand. During the right-hand-movement imagery task, the dorsolateral prefrontal cortices (BAs 9, 10 and 46), the supplementary motor area (SMA), the pre motor cortex, the occipital cortices, the anterior cingulate gyrus and the cerebellum were significantly activated. Only in two subjects (YM and TK) did the present imagery task activate the right inferior parietal lobule (IPL) and the left superior temporal gyrus (STG), which are known to be involved in imagery requiring visuospatial information and in silent vocalization of the mimesis, respectively. This finding may exemplify that different imagery strategies activate different brain sites.

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We studied the possibility of making an objective diagnosis of mild cognitive impairment. An image of the cerebral parenchyma was created from original MR images, and the brain, hippocampus, parahippocampal gyrus, and the amount of the features from the co-occurrence matrix were measured. When the brain-intracranial ratio, hippocampus-intracranial ratio, and parahippocampal-intracranial ratio were computed, a significant difference was not detected. Discriminant analysis using the hippocampus-intracranial ratio and parahippocampal-intracranial ratio showed an overall accuracy of 63.8%. These are not sufficient results to use clinically. Therefore it is possible to make an objective diagnosis of mild cognitive impairment using the co-occurrence matrix. A statistically significant difference was found in 8 of the 13 features obtained from the co-occurrence matrix. Moreover, discriminant analysis using the eight features showed an overall accuracy of 85.1%. These results indicate that they can be used as an objective diagnostic technique for mild cognitive impairment.

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The equivalent cross-relaxation rate (ECR) is a measurement method to evaluate a change in organizational structure quantitatively utilizing MRI. The objectives of this study are to understand the characteristics related to water contents in degenerative lumbar intervertebral discs, and to investigate the usefulness of quantitative evaluation using ECR in order to find as early as possible disordered discs. Seven normal volunteers and four asymptomatic volunteers with degeneration in lumbar intervertebral discs, 21 to 26 years of age, were studied using a SIGNA model of GE Medical Systems equipped with a 1.5T clinical scanner and spine coil. The ECR values were defined as the percentage of signal loss between unsaturated and saturated images. The results showed that the ECR value of annulus fibrosus in an intervertebral disc was higher than nucleus pulposus. Furthermore, it was found that the ECR value of nucleus pulposus (L5-S1) with degeneration was significantly higher than that without degeneration. It was considered that this result reflected an increase of water contents in the degenerative nucleus. This study suggests that the ECR value of a nucleus could be an effective parameter to diagnosis of degenerated discs or grades of disorder.

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