Toshiaki Taoka

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PURPOSE Recently, imaging-based tumor volume before, during, and after radiation therapy (RT) has been shown to predict tumor response in cervical cancer. However, the effectiveness of different methods and timing of imaging-based tumor size assessment have not been investigated. The purpose of this study was to compare the predictive value for treatment(More)
PURPOSE Our aim was to determine whether diffusion anisotropy and diffusivity of white matter tracts of the temporal stem in patients with Alzheimer (AD) can be evaluated independently by using diffusion tensor tractography. MATERIALS AND METHODS Subjects included 15 patients with AD (11 women and 4 men; mean age, 74 years) and 15 age-matched control(More)
Mild cognitive impairment (MCI) is considered the transitional stage between normal cognition and dementia. The aim of this study was to use tractography based analysis to elucidate alterations in subjects with MCI compared with subjects with early Alzheimer's disease (AD) and controls. Seventeen subjects with early AD, 16 with MCI and 16 controls underwent(More)
The aim of this study was to investigate the morphologic changes of the pituitary gland in patients with the clinical diagnosis of idiopathic intracranial hypertension (IIH). Qualitative and quantitative analyses of pituitary morphology were performed in normal subjects (n = 23), patients with the clinical diagnosis of IIH (n = 40), and patients with acute(More)
BACKGROUND AND PURPOSE Tract-based analysis can be used to investigate required tracts extracted from other fiber tracts. However, the fractional anisotropy (FA) threshold influences tractography analysis. The current study evaluated the influence of the FA threshold in measuring diffusion tensor parameters for tract-based analysis of the uncinate(More)
BACKGROUND AND PURPOSE Specific change of persistent hyperintensity/hypointensity on T1-weighted (T1W) and T2-weighted (T2W) MRI, respectively, has been reported to develop in the human basal ganglia after brief hemispheric ischemia. We investigated whether this ischemic change observed in humans could be reproduced experimentally in rats after brief middle(More)
BACKGROUND AND PURPOSE Visual field defects sometimes occur after temporal resection surgery. Our purpose was to evaluate the correlation between visual field defects caused by temporal lobe resection and the degree of resection of the Meyer loop, as assessed by diffusion tensor tractography. MATERIALS AND METHODS We examined 14 patients who underwent(More)
OBJECTIVES Some patients with progressive supranuclear palsy (PSP) present with cerebellar dysfunction. Severe degeneration of the cerebellar dentate nucleus (CDN) was evident in these patients. We evaluated signal intensity on MRI in the CDN of PSP patients with or without cerebellar ataxia. PATIENTS AND METHODS We reviewed the clinical histories and(More)
Brief focal ischemia leading to temporary neurological deficits induces delayed hyperintensity on T1-weighted magnetic resonance imaging (MRI) in the striatum of humans and rats. The T1 hyperintensity may stem from biochemical alterations including manganese (Mn) accumulation after ischemia. To clarify the significance of this MRI modification, we(More)
PURPOSE We measured the time lags between the start or end of tasks and signal changes in functional MRI (fMRI) for various age groups and evaluated the age correlation of the time lags. METHODS Forty subjects, 20-76 years old, were evaluated. fMRI was performed with and echo planar imaging sequence at 0.5 s intervals. We measured the time for the signal(More)