A comparison of gray scale ultrasound and radionuclide imaging for the detection of focal hepatic lesions: Open shutter technique

Abstract
A conventional B scan ultrasound unit was modified by the addition of a specially built logarithmic amplifier and a high resolution nonstorage oscilloscope, as suggested by Taylor and Carpenter. One hundred five consecutive patients submitted for radionuclide imaging of the liver were examined with ultrasound using a standardized scanning system. The ultrasound technique produced scans that were technically poor or inadequate in 37 per cent of the patients studied. In the studies in which there has been confirmation, the ultrasound diagnosis was accurate in 73 per cent and the radionuclide diagnosis was correct in 83 per cent. The combined accuracy of the two studies was 93 per cent. In 11 patients, ultrasound more clearly defined the lesions that were demonstrated by both techniques or demonstrated the nature of suspicious or equivocal areas on the radionuclide images. In 48 patients, the radionuclide scan imaged the liver more completely or demonstrated lesions more clearly than did the ultrasound examination. This specific approach to ultrasound gray scale imaging appears to be a valuable supplemental tool to radionuclide imaging, but at its present stage of development cannot replace it as a routine screening technique for hepatic disease.