Failure of operative cholangiography to prevent retained common duct stones

In a survey of all explorations of the common bile duct for stones in three Syracuse hospitals between 1963 and 1970, we selected 302 patients who had had T tube cholangiograms before discharge. Retained stones were identified in forty-one patients (14 per cent). In thirty of these forty-one patients operative cholangiography performed after surgical exploration failed to disclose the stones. (In eleven patients no operative study was performed.) Operative cholangiography also disclosed stones that would have been overlooked. However, in this series, it seems that undue reliance had been placed on cholangiography and that some surgeons were unaware of one or more of the following pitfalls in the procedure, each of which is illustrated in this report: (1) Contrast material too dense: If the limbs of the T tube cannot be seen within the duct, stones may also be obscured by the contrast material. Laboratory tests have led us to use two parts saline solution to one part 50 per cent Hypaque or its equivalent. (2) Stone in motion: If all exposures are made during injection, the stone may be rolling and not visualized. (3) Incomplete filling: Finger occlusion of the distal duct will assure complete proximal filling. Dilute contrast medium allows filling without obscuring stones. (4) Failure to get cassette properly positioned or to use proper exposure: We have found that Polaroid film with the ducts filled serves equally as well as an early preliminary film to avoid these errors. (5) Duct over spine: We position the patient on the table with the left side elevated 15 to 20 degrees, which rotates the duct off the vertebra. (6) Superimposition of ducts: Exposures must be made in at least two projections to avoid this pitfall. (7) Failure to consult (or heed) the radiologist: Confidence in inadequate studies is inappropriate and, even if excellent cholangiograms can be obtained, the completeness of surgical exploration must in no way be lessened. Only then will the surgical and radiographic searches for retained stones be additive.