OBJECTIVES To evaluate the preliminary results obtained using diffusion-weighted magnetic resonance imaging and the apparent diffusion coefficient for planning computed tomography-guided biopsies of selected mediastinal lesions. METHODS Eight patients with mediastinal lesions suspicious for malignancy were referred for computed tomography-guided biopsy. Diffusion-weighted magnetic resonance i...

Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord in vivo. Diffusion tensor imaging technology is a sensitive method to diagnose spinal cord injury; fiber tractography visualizes the white matter fibers, and directly displays the...

What is a “diffusion coefficient” or “diffusion tensor” in living tissue, anyway? While the measurement of the self-diffusivity in an NMR tube represents a "gold standard", in complex media particularly in living tissue, water “diffusivity” ceases to have a clear meaning or definition. The apparent diffusion coefficient (ADC) and apparent diffusion tensor (ADT) concepts were introduced to answe...

OBJECTIVE To determine the associations of liver lobe-based magnetic resonance diffusion-weighted imaging findings using multiple b values with the presence and Child-Pugh class of cirrhosis in patients with hepatitis B. METHODS Seventy-four cirrhotic patients with hepatitis B and 25 healthy volunteers underwent diffusion-weighted imaging using b values of 0, 500, 800 and 1000 sec/mm2. The ap...

Consensus forecasts are ine¢ cient, because the weight placed on aggregate new private information relative to the prior re‡ects the optimal choices of the underlying individual forecasters— whose private signals are noisier individually than in aggregate— and as a result the consensus forecast over-weights the prior (Lim, Kim and Shaw, 2001). This paper assesses the empirical relevance of this...

background: the aim of the present study was to estimate chronological age based on third molar development and to determine the association between dental age and third molar calcifi cation stages. materials and methods: in this cross-sectional study, 505 digital panoramic radiographs of 223 males (44.2%) and 282 females (55.8%) between the age of 6 and 17 were selected from patients who were ...