Journal of Ultrasound in Medicine, Vol 2, Issue 12 535-538, Copyright © 1983 by American Institute of Ultrasound in Medicine
Experimental assessment of imaging variables associated with operative ultrasonic and radiographic cholangiography
J. Machi, B. Sigel, D. G. Spigos, J. C. Beitler and J. R. Justin
The comparative accuracies of operative ultrasonic and radiographic
cholangiography to detect biliary calculi 1 mm in diameter inside tubes of
different calibers were assessed. One hundred eighty tubes were prepared to
provide ten tubes each for the following variables: three sizes of tubes
(6, 13, 20 mm), three concentrations of contrast material (15, 30, 60 per
cent), and presence or absence of calculi. Real-time B-mode ultrasound
scans with a single gain and time gain compensation (TGC) setting were
performed and contrast radiographs were also made at a single optimal
exposure. Sixty ultrasonic and 180 radiographic examinations were studied.
All ultrasonic interpretations were correct regardless of size of tube.
Under optimal conditions, radiographic interpretations were also correct.
However, whereas a single gain and TGC setting was applicable for all
ultrasound examinations, variable contrast concentrations were required for
the best radiographic imaging. Optimal radiographic contrast concentrations
differed with tube diameters. The authors conclude that both ultrasonic and
radiographic contrast imaging are highly accurate for the detection of
small biliary calculi. However, contrast radiography requires stricter
optimization of variables needed to provide the high accuracy. Thus,
operative ultrasonography may be a more practical and reliable diagnostic
procedure because of high sensitivity and greater ease of performance and
interpretation.
