We describe a cholesterol gallstone with an unusual macroscopic appearance and only mild acoustic shadowing on ultrasonography with a 3.5 MHz transducer used in vivo; there was greater shadowing using 5.0 and 7.5 Mhz transducers in vitro.
LeopoldGR, AmbergJ, GosinkBB, MittelstaedtC.Gray scale ultrasonic cholecys-tography: A comparison with conventional radiographic techniques. Radiology1976;121:445–448.
2.
GradeM.TaylorKJW, RosenfieldAT, De CraffCS, MinihanP.Surgical and pathological correlation of cholecystosonography and cholecystography. AJR1978;131:227–229.
3.
CooperbergPL, BurhenneHJ.Real-time ultrasonography, diagnostic technique of choice in calculous gallbladder disease. N Eng J Med1980;302:1277–1279.
4.
CarrolBA.Gallstones: in vitro comparison of physical, radiographic, and ultrasonic characteristics. AJR1978;131:223–226.
5.
TaylorKJW, JacobsonP.JaffeCC.Lack of an acoustic shadow on scans of gallstones: a possible artifact. Radiology1979;131:463–464.
6.
FillyRA, MossAA, WayLW.In vitro investigation of gallstone shadowing with ultrasound tomography. JCU1979;7:255–262.
7.
GoodLI, EdellSL, SolowayRD, TrotmanBW, MulhernC, ArgerPA.Ultrasonic properties of gallstones, effect of stone size and composition. Gastroenterology1979;77:258–263.
8.
ParulekarSG.Ultrasonic detection of calcification in gallstones: ‘the reverberation shadow.’J Ultrasound Med1984;3:123–129.
