Hepatic dynamic sequential CT: section enhancement profiles with a bolus of ionic and nonionic contrast agents.

Abstract

The enhancement characteristics in different portions of the liver during dynamic sequential bolus computed tomography (CT) with iodinated contrast material (DSBCT) were prospectively evaluated in 75 patients by using iothalamate meglumine, iopamidol, and iohexol (25 patients received each agent). After baseline noncontrast CT was performed, DSBCT was performed with a 180-mL intravenous bolus administered at 2 mL/sec. Scanning was started 25 seconds after the bolus was initiated, by using a 3-second scan time and rapid cephalocaudal table incrementation, yielding contiguous 8-mm-thick sections at a rate of nine sections per minute. On postcontrast images, peak enhancement was 115% for iopamidol and 117% for iohexol, both of which were superior to iothalamate meglumine at 95% (P less than .05). After peaking, enhancement then decreased for all three contrast agents, although the decline was more precipitous for iothalamate meglumine. Enhancement on the more caudal sections with both iopamidol and iohexol was superior to that with iothalamate meglumine (P less than .05). The data suggest that the enhancement characteristics for the two nonionic agents may be more optimal for detection of focal hepatic lesions than the ionic agent.

Diagnosis of fatty infiltration of the liver on contrast enhanced CT: limitations of liver-minus-spleen attenuation difference measurements

“…These factors include total dose of contrast, body weight, cardiac output, and location of intravenous access [13][14][15][16][17][18][19]. Whether the contrast is ionic or nonionic may also affect liver enhancement, although conflicting studies have been reported [19][20][21]. Splenic enlargement or liver disease are additional variables that can alter the relative perfusion of these organs and change the expected L-S attenuation difference after contrast, as was illustrated by the example in Figure 4.…”

Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT

“…However, the hypervascular pannus reflects the active stage of RA leading to bone and joint destruction, and thus it was suggested that differentiation between this type of pannus and other changes might be important for therapeutic management [6,7,14,15]. Contrast material changes the densities of soft tissue by uptake of contrast agent depending on the degree of vascularization [16,17]. Thus, the different densities and the increase of density of the inflammatory soft tissue on the pre-and post-contrast scans were assessed quantitatively and also evaluated by visual image interpretation in order to characterize the different tissues in this CT study as this was also performed in recently published MRI studies [6,7].…”

Assessing the effectiveness of X–ray contrast media for abdominal computed tomographic examinations: comparison of four low–osmolality agents

“…By improving the CT enhancement image of normal liver parenchyma and maximizing the liver-to-lesion contrast in most clinical situations, the use of XRCM will offer significant information for better diagnosis and patient management. Recent studies have reported superior enhancement of the CT of the normal liver with nonionic contrast material when compared with ionic contrast agents (6,7). However, the high cost of low-osmolality iodinated intravenous contrast agents is forcing radiologists and pharmacists to consider carefully the most cost-effective agent to use in abdominal examinations.…”