Multidetector helical computed tomography of the liver: comparison of hepatic enhancement using two different contrast media strategies.

Rationale And Objectives: The purpose of this study was to compare hepatic enhancement characteristics using two different contrast media injection protocols with multidetector helical computed tomography.

Materials And Methods: Twenty-three patients with known or suspected liver lesions scheduled to undergo biphasic hepatic multidetector helical computed tomography were randomized into one of two groups: (1) 150 mL of iopamidol (300 mgI/mL) at 5 mL/second, or (2) 100 mL of iopamidol (370 mgI/mL) at 4 mL/second. Unenhanced images were acquired initially, followed by both hepatic arterial phase (scan delay, 33 seconds) and portal venous phase (PVP; scan delay, 65 seconds) imaging.

Helical CT for nephrolithiasis and ureterolithiasis: comparison of conventional and reduced radiation-dose techniques.

Purpose: To determine the accuracy of unenhanced helical computed tomography (CT) performed at reduced milliampere-second, and therefore at a reduced patient radiation dose, by using conventional unenhanced helical CT as the standard.

Materials And Methods: Fifty patients with acute flank pain who weighed less than 200 lb (90 kg) were prospectively recruited for this study. Conventional helical CT scans were obtained with patients in the prone position by using 5-mm-thick sections, 140 kVp, 135-208 mAs (mean, 160 mAs), and a pitch of 1.

Computed tomography urography, three-dimensional computed tomography and virtual endoscopy.

Spiral computed tomography technology allows an entire body region to be imaged as a continuous volume of computed tomography data. The acquisition of genitourinary images can be performed at different intervals after intravenous contrast injection in order to characterize the renal vasculature, the renal parenchyma or the collecting system. Computed tomography scanning as contrast is excreted into the collecting system is termed a 'computed tomography urogram'.

Pseudoenhancement of simple renal cysts: a comparison of single and multidetector helical CT.

Purpose: The purpose of this work was to compare the extent of pseudoenhancement (artifactual increase in measured attenuation of a simple cyst after contrast medium administration) in a phantom model on single detector and multidetector helical CT scanners.

Method: The phantom consisted of four water-filled spheres varying in size from 8 to 28 mm, suspended in an aqueous contrast medium bath. Iodine concentration in the bath was varied: 0, 6, 12, and 24 mg/ml corresponding to attenuation values of 0, +108, +180, and +300 HU.