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Phase
3: Cholangiography
The technique is modified in cases requiring cholangiography. Prior to
placement of clips or any division of structures, the cystic duct is
dissected meticulously as close as possible to the gallbladder neck. The
cystic duct is clipped at its junction with the gallbladder. The clip
applier is withdrawn and a small transverse incision is made along the
anterior aspect of the cystic duct with an endo-scissor. Due to the
arterial supply to the duct, one can expect bleeding from the cut edge.
Cautious cauterization of the feeding artery may improve visualization.
After incising the duct, the operator should note an efflux of bile from
the defect, indicating entrance into the lumen. If bile is not seen,
gently milking the duct from a medial to lateral direction can sometimes
better define a small transmural defect. This milking action also gives
the operator a sense of duct compliance, which if low, may suggest
impacted cystic duct stones medial to the incision. Once an adequate
incision is made, a cholangiocatheter fitted with a grasper is inserted
through the subxiphoid port. Alternatively, the cholangiocatheter may be
placed through a needle inserted into the right upper quadrant under
direct vision, or through one of the accessory cannulae. It may be
helpful to fit the catheter with a guide wire and saline filled syringe.
Akin to a Seldinger technique, the guidewire can be used as a guide to
access the difficult duct. Saline can be injected slowly during catheter
insertion to aid in distension of the duct or clearing any remaining
bleeding along the cut edge. The spiral valves of Heister within the
lumen of the cystic duct may cause resistance to insertion of the
catheter. However, only a small portion of the tip of the catheter need
be inserted for an adequate study if the duct is open. The catheter is
inserted into the duct, and the grasper is gently closed around it. The
jaws of the grasper should enclose the entire width of the duct for
optimal results. The catheter is irrigated with saline. Any leak noted
around the catheter will result in extravasation of contrast, and
requires repositioning of the catheter. Dilute contrast, devoid of air
bubbles, is then injected through the catheter. The contrast wave is
followed radiographically, preferably using real time fluoroscopy. The
following should be visible on a normal cholangiogram:
1. The cystic duct
2. The common bile duct with its hepatic bifurcation and biliary
radicles
3. Contrast in the duodenum
4. Absence of filling defects in the CBD
If filling defects are noted within the CBD or cystic duct, double check
the contrast to insure that no air bubbles are present. Bubbles in
themselves may cause filling defects but should clear with repeated
injections, and should rise with elevation of the head of the bed. The
overall length and direction of the cystic duct should be noted to
minimize CBD injury during clipping and division of the cystic duct.
Once the cholangiogram is completed, remove the catheter and proceed
with the remainder of the operation as described.
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