[Spiral computer tomography in diagnosis of hepatic diseases]

Spiral computer tomography (SCT) is a new method of computer tomography by which, in contrast to conventional CT, the information about absorptional capacity of tissues is obtained without omission of images which makes it possible to build MPR and 3D of a very high quality. 205 patients with diseases of hepatopancreatoduodenal area were examined, in 189 patients the diagnosis being verified. Optimal technique of intravenous bolus contrasting in SCT was developed. Using various time interval between the start of the scanning and the beginning of infusion of contrast media, it is possible to obtain primary image of the arteries (arterial phase of contrasting, time of delay 18-25 sec.), the picture of veins and the image of saturation of hepatic parenchyma--(venous return phase, time of delay 60-80 sec.), to reveal characteristics of contrasting of the liver masses during delay (8-15 min) phase. The largest quantity of masses are revealed in arterial phase of contrasting. Specific features of contrasting in hemangiomas and malignant tumors of the liver has been revealed. Hemangiomas absorb contrast medium already at the early phase as hypercontrasted lacunas in an outlying areas, at a late phase they are hyperdenced in relation to hepatic parenchyma. Primary and metastatic tumors of the liver accumulate contrast medium in an early phase along the whole area and quickly lose contrast medium during parenchymal phase. The method of contrast intensification enables evaluation of interrelation between tumor and vessels, to determine passage of hepatic arteries and branches of portal and hepatic veins, to visualise choledochal duct, to determine the distance between hepatic and tumor surface, and to produce these data as a view of multiplanar and three-dimensional image (reconstruction). The effectiveness of obtained reconstructions in planning of the extent of surgical intervention is demonstrated.