CT for Gallstones

"An anthropomorphic phantom was scanned with or without gallstones at CT by using 80, 100, 120, and 140 kVp. The sensitivity for gallstone detection was significantly higher at 140 kVp than at lower voltage settings, regardless of gallstone size. CT attenuation measurements were not useful for determination of gallstone composition. Abdominal CT performed at 140 kVp may be useful when gallstone disease is of clinical concern. "

Reference-
Radiology 2006;241:546-553