Sonography is valuable in the accurate diagnosis of gallstones. All but the smallest stones attenuate sound, a phenomenon known as acoustic shadowing. However, when small focal nonshadowing opacities are present, the diagnostic question is whether they represent small calculi. In a four-year review of sonographic studies performed at Henry Ford Hospital, 12 patients in whom this sonographic finding was present underwent cholecystectomies, and seven had calculi (58%). If the presence of gallstones is the factor that will determine whether surgery will be performed, we recommend a repeat examination to confirm the presence of the focal opacities and to elicit acoustic shadowing.
Sandler, Michael A.; Biunno, Eileen M.; Gross, Martin L.; and Madrazo, Beatrice L.
"The Incidence of Calculi in Focal Nonshadowing Echogenicity in the Gallbladder,"
Henry Ford Hospital Medical Journal
: Vol. 33
Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol33/iss2/10