Diagnostic value of SPIO-mediated breath-hold, black-blood, fluid-attenuated, inversion recovery (BH-BB-FLAIR) imaging in patients with hepatocellular carcinomas.

Purpose: We assessed the value of adding a breath-hold, black-blood, fluid-attenuated, inversion recovery (BH-BB-FLAIR) sequence with a small motion-probing gradient (b=10 s/mm(2)) using superparamagnetic iron oxide (SPIO) to our present studies that utilize SPIO to detect hepatocellular carcinoma (HCC). We used inversion recovery (IR) in a FLAIR sequence to suppress signals from cysts and a low b-value to suppress vessel signals and provide higher signal to noise than that using high b-value diffusion-weighted imaging. Use of SPIO is expected to reduce the signal in both normal liver parenchyma and in most benign lesions.

Application of subsecond rotation scan to helical CT for lung cancer screening.

Purpose: To clarify whether the benefit of a reduced effective scan width obtained using a smaller pitch outweighs the disadvantage of increased noise in the application of a subsecond helical CT to mass screenings for lung cancer.

Materials And Methods: Twenty-two helical CT scans of the lung were obtained in 11 healthy subjects using the following parameters: 1) scan 1 was performed at 120 kVp, 50 mA, 10-mm collimation, 1-second/rotation, helical pitch of 2.0; and 2) scan 2 was performed at 120 kVp, 50 mA, 10-mm collimation, 0.

Three-phase CT examination of the pancreatobiliary region using multislice CT with 1-mm collimation.

Purpose: To evaluate the degree of contrast enhancement and accuracy of imaging of the circulatory phase in the first-pass, second-pass, and third-pass acquisitions in the pancreato-biliary region with 1-mm collimation obtained by multislice computed tomography (CT).

Materials And Methods: In 53 patients, two sequential acquisitions from the porta hepatis to the pancreas were performed during a single breath-hold, followed by a third-pass acquisition including the liver beginning 15 sec after the second-pass acquisition. Contrast enhancement in each acquisition was measured in the aorta, portal vein and its branches, and pancreas.

Lung: feasibility of a method for changing tube current during low-dose helical CT.

A method for changing the tube current during helical scanning was applied to low-dose computed tomography (CT) in the lung. The changing method resulted in significant equalization of image noise in various lung sections compared with that at scanning with constant tube current. Detectability of nodules was equivalent between 60 mA and the changing method, whereas degradation occurred at 20 mA.