The cystic duct sign during morphine-augmented cholescintigraphy.

Visualization of a "dilated cystic duct" during standard hepatobiliary imaging represents a potential source of false-negative cholescintigraphy. Intravenous morphine, commonly used to shorten study time and improve the specificity of hepatobiliary imaging, may, by virtue of its pharmacologic/physiologic actions, accentuate the appearance of a "dilated cystic duct." We present a case of transient cystic duct visualization following morphine administration in a patient with an obstructing cystic duct calculus.