Radiological anatomy of the bile ducts based on intraoperative investigation in 250 cases

Summary

Intraoperative cholangiograms were studied in 250 patients. Analysis of the data obtained led to the establishment of a protocol for intraoperative cholangiography aimed at identification of anatomical anomalies and variations. Diagnosis of the latter must be achieved in order to avoid possible intraoperative complications. The common hepatic duct was formed by the junction of the right and left hepatic ducts in 52% of the cases studied. Absence of convergence of the posterior and anterior rami of the right hepatic duct was found in 30% of cases. Anatomical variations of the right sectorial duct system were seen in 12% of cases. Conversely, variations of the left sectorial duct system were rarely seen (2% of cases). Careful examination of the intraoperative cholangiograms led us to suspect certain anatomical variations in close to 1% of cases. These variations included abnormal hepatocystic duct, which if undiagnosed could lead to choleperitoneum or inadvertent ligation of the right hepatic duct. An abnormal hepatocystic duct terminating on the gall bladder was found in one patient. Study of the origin of the common bile duct allowed us to define the mode of termination of the cystic duct (on the right margin of the common hepatic duct in 80% of cases) and to identify a short choledocus in 2% of cases. Finally, variations of the duodenal termination of the common bile duct were studied and reflux into the pancreatic duct was seen in 27% of cases. However, the pathological significance of such reflux was rarely found.

Résumé

L'étude de 250 documents permet de définir un protocole de lecture des cholangiographies peropératoires à la recherche d'anomalies ou de variations, dont la méconnaissance peut exposer à des complications per-opératoires. L'analyse du cholangiogramme intra-hépatique permet de retrouver une disposition modale dans 52% des cas. L'absence de convergence des canaux sectoriels, latéral et paramédian droits est notée dans 30% des cas. Les variations des canaux sectoriels droits sont retrouvées dans 12% des cas. A l'opposé, les variations du système canalaire gauche sont rares (2%). Dans près de 1% des cas, la lecture attentive du cholangiogramme permet de soupçonner certaines variations, tels les canaux cysto-hépatiques dont la méconnaissance expose à un cholépéritoine ou à la ligature d'un canal hépatique droit, à implantation vésiculaire (1 cas). L'étude du confluent biliaire inférieur précise le mode d'implantation du canal cystique (80% des cas sur le bord droit du canal hépatique commun) ainsi que l'éventualité d'un vrai cholédoque court (2% des cas). Enfin, deux aspects sont envisagés: les variations d'implantation terminale du cholédoque au niveau du duodénum et la constatation d'un reflux wirsungien noté dans 27% des cas. La signification pathologique d'un tel reflux est rarement établie.