Due to reliance upon geometric assumptions and foreshortening issues, the traditionally utilized transthoracic two-dimensional echocardiography (2DTTE) has shown limitations in assessing left ventricular (LV) volume, mass, and function. Cardiac magnetic resonance imaging (MRI) has shown potential in accurately defining these LV characteristics. Recently, the emergence of live/real time three-dimensional (3D) TTE has demonstrated incremental value over 2DTTE and comparable value with MRI in assessing LV parameters. Here we report 58 consecutive patients with diverse cardiac disorders and clinical characteristics, referred for clinical MRI studies, who were evaluated by cardiac MRI and 3DTTE. Our results show good correlation between the two modalities.

Degeneration of the corpus callosum (CC) is evident in the pathogenesis of Alzheimer's disease (AD). However, the correlation of microstructural damage in the CC on the cognitive performance of patients with amnestic mild cognitive impairment (aMCI) and AD dementia is undetermined. We enrolled 26 normal controls, 24 patients with AD dementia, and 40 single-domain aMCI patients with at least grade 1 hippocampal atrophy and isolated memory impairment. Diffusion tensor imaging (DTI) with fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (DA), and radial diffusivity (DR) were measured. The entire CC was parcellated based on fiber trajectories to specific cortical Brodmann areas using a probabilistic tractography method. The relationship between the DTI measures in the subregions of the CC and cognitive performance was examined. Although the callosal degeneration in the patients with aMCI was less extended than in the patients with AD dementia, degeneration was already exhibited in several subregions of the CC at the aMCI stage. Scores of various neuropsychological tests were correlated to the severity of microstructural changes in the subregional CC connecting to functionally corresponding cortical regions. Our results confirm that CC degeneration is noticeable as early as the aMCI stage of AD and the disconnection of the CC subregional fibers to the corresponding Brodmann areas has an apparent impact on the related cognitive performance.

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Compressed breast thickness is useful for quantifying dimensions and percentage glandular content of a model breast. The adjustable model breast developed in this study can offer greater flexibility in the determination of breast dimensions for mammographic dosimetry assessment of Taiwanese women.

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