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Prospective evaluation of selective intraoperative cholangiography in preventing retained stones.

OBJECTIVE
To determine the effectiveness of selective intraoperative cholangiography (IOC) during gallstone surgery in preventing retained bile duct stones. We reviewed the design and application of our procedure for deciding when to use IOC.


METHODS
This was a prospective, 4-year observational study with delayed cohort evaluation after a follow-up period of 2-6 years. We studied 672 consecutive patients who underwent cholecystectomy at the General Surgery Unit of the Motril Hospital in Motril (Granada province), Spain, because of symptomatic cholelithiasis. The study period was from September 1991 (when we adopted a protocol to select patients for IOC) to June 1995. Clinical, biochemical and ultrasonographic data, operative findings, and clinical and early postoperative data were collected prospectively. Follow-up clinical evaluation was done by personal, postal or telephone interview. Biochemical, sonographic and (when available) endoscopic examinations were done for patients suspected of having residual bile duct stones.


RESULTS
Intraoperative cholangiography was not done during simple cholecystectomy in 453 patients. In 335 of these patients this decision was correct, and only 1 case of suspected residual stone was found (0.3%). In the other 188 patients the decision to omit IOC was arbitrary (i.e., not based on the protocol); among these patients we found 5 cases (2 suspected and 3 proven) of residual stones (4.2%). The difference was significant according to Fisher's exact test (p = 0.005).


CONCLUSIONS
In some patients who undergo cholecystectomy, IOC may be omitted without major risk of retained duct stones. Patients in whom IOC will not be done must be selected strictly according to a well-designed protocol to avoid increasing the risk perceptibly.