To the Editor.—To facilitate placement, a recently described cannula for intraoperative cholangiography1 has been modified by lengthening the metal stem so that it may be held directly for insertion into the cystic duct (Fig 1). The tip is closed, smooth, and blunt, and the two openings are on the sides of the cannula proximal to the tip. The 18-gauge metal tubing is stiff enough to provide good control but flexible enough to allow some sense of tissue resistance. This cannula has been prepared either with or without a metal collar, but in either case it rarely becomes dislodged.
Procedure.—Fill a syringe, the attached two-way stopcock, and the cannula instrument with contrast material, being certain that it does not contain any air bubbles. Close the stopcock. Insert the cannula directly into the cystic duct through a small incision and fix it in place with a small metal clip