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Cystic Duct Cholangiogram
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Cystic Duct Cholangiogram | ||
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Related narrative: Cystic Duct Cholangiogram 7 cc of dilute contrast (50% Hypaque mixed 50/50 with saline) was slowly injected under fluoroscopic control. Four 4 mm stones were seen in the distal common duct. The ductal system was dilated, biliary radicals of all major ducts filled without filling defects and there was a trickle of contrast into the duodenum past the stones. Injection was stopped at the first evidence of pancreatic duct filling. Of interest, the anterior division of the right hepatic duct (segments V and VIII: see hepatic segmental atlas) drained into the left hepatic duct (see biliary variation). The cholecystectomy was completed and the patient went for post operative ERCP with sphincterotomy and stone extraction. Comment: A patient with resolving gallstone pancreatitis and multiple small stones such as this one is best served with expedient laparoscopic cholecystectomy to preclude further stone passage and recurrent pancreatitis. Most small (< 4 mm) stones pass spontaneously. If the pancreatitis is improving, preopertaive ERCP is not recommended since intraoperative cholangiography showing a clear duct might preclude the need for the procedure. If stones were found, postoperative ERCP has a 95% success rate in experienced hands. If that failed, the patient could still be observed for probable passage of these small stones. Worst case scenario, if the stones did not pass, open common duct exploration could be performed. Intraoperative trans-cystic common duct exploration was not considered because it is highly technical, invasive, and in other than expert hands, potentially more traumatic than ERCP. Several fine points about cholangiography should be noted. The patient should be rotated slightly to the right to move the common duct, which is close to a midline structure, off the spinal column for clear visualization. If a three-way valve system is used, care must be taken to ensure there are no air bubbles in the system that could mimic stones. If there is any question about a defect, reverse Trendellenberg position will cause a bubble to float up into the biliary radicals. Introducing the catheter tip into the cystic duct can be difficult because of the spiral valves (of Hyster) and/or because of cystic duct stones. Gentle irrigation with saline during introduction can dilate the duct and facilitate passage. The catheter tip should be introduced no farther than 1cm. this allows adequate depth for injection while precluding perforation of the cystic or common duct by the catheter tip. In addition, if the tip is advanced farther, it may point distally in the common duct and fail to fill the hepatic biliary tree. The minimal amount of contrast injection necessary should be used to ensure a dilute dye column that will not obscure small defects, and to prevent pancreatic duct reflux. Seven cc's is usually sufficient. A second injection of a similar amount may be necessary if the contrast empties rapidly into the duodenum. Surgeons are expected to accurately interpret their cholangiogram results intraoperatively and make treatment decisions based on those interpretations. In addition to the basic criteria for a normal cholangiogram (diameter, biliary radicals, filling defects, extravasation, passage of contrast into the duodenum), variations in anatomy must be noted. The surgeon is at a disadvantage, even with the quality of state-of-the-art intraoperative cholangiography, because of the inability to move the patient into multiple positions as the interventional radiologist does. If there is any question about a study, it is important to get an expert radiologist to assist in the interpretation. The majority of surgeons looking at this cholangiogram, fail to note the ductal anomaly. This is partly due to the fallacy of focusing on obvious pathology (the stones) before completing a systematic evaluation of all aspects of the study, and partly due to unfamiliarity with unusual biliary variations.
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