| Theme | Imaging Diagnostics of Liver Disease | |
|---|---|---|
| Title | Diagnosis of Hepatic Tumors with CT Scanning | |
| Publish Date | 2002/01 | |
| Author | Masashi Kimura | Department of Radiology, Wakayama Medical University |
| Author | Morio Sato | Department of Radiology, Wakayama Medical University |
| Author | Motoki Nakai | Department of Radiology, Wakayama Medical University |
| Author | Hiroki Minamiguchi | Department of Radiology, Wakayama Medical University |
| Author | Yasukazu Shioyama | Department of Radiology, Wakayama Medical University |
| [ Summary ] | Improvements in CT technology have dramatically increased our ability to detect and diagnose liver abnormalities, particularly neoplastic disease. Because of the high prevalence of hepatic tumors in patients referred for abdominal CT examinations, contrast administration and scanning techniques are usually optimized for detection of hepatic tumors with abdominal CT scanning. The ability of CT contrast techniques to show hepatic tumors is enhanced by the dual blood supply to the liver. The liver is different from all other abdominal organs because of this dual blood supply. The hepatic artery delivers 25% of the blood flow to the liver, and the portal vein delivers 75%. This, and the fact that most tumors of the liver have only a hepatic arterial blood supply and receive little or no flow from the portal vein, are the key physiological parameters which make contrast-enhanced CT scanning so successful in detecting tumors. Compared with the slow, prolonged rates of contrast administration or unenhanced CT, dynamic incremental bolus, contrast-enhanced CT has been found to be the most sensitive method of contrast administration for detecting hepatic tumors. This technique requires the use of a power injector to ensure a rapid and sustained rate of infusion of contrast material and to avoid scanning during the equilibrium phase of contrast enhancement. Concerning scanning time, images covering thin slices may now be obtained quickly, due to the advent of multi detector helical CT (MDHCT), with multiple detectors. This results in improvements in the spatial resolution of the axial direction and also of temporal resolution in dynamic studies. |
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