[Secondary liver lesions studied with double-helix spiral computed tomography: first experience]

The authors report their early personal experience with double-helix spiral CT (CT Twin Elscint) in the study of liver metastases. This work was aimed at optimizing the study technique and at assessing the diagnostic accuracy of this method. The high temperature developed by CT Twin and the presence of a double row of detectors permit to acquire proper length sequences (with 6.5 mm slice thickness) within a short scanning time which is easy for the patient to tolerate without breathing and moving. Two hundred and thirty patients were examined with US for focal hepatic lesions and then submitted to spiral CT: spatial and density resolution were higher with spiral CT than with US, and the former technique permitted the whole liver to be studied without any partial volume artifacts, which allowed us to confirm all the lesions depicted with US and to detect other lesions, missed at US, in 20% of patients. The choice of the proper time between contrast administration and sequence acquisition is sufficient to permit the detection of focal lesions, if the liver is studied in the portal phase. The authors stress the yield of spiral CT, especially with the double-helix technique, in studying liver metastases.