The Curious Case of the Choledochal Cyst—Revisiting the Todani Classification: Case Report and Review of the Literature

Abstract

Choledochal cysts (CCs) are rare occurrences presenting as dilatations of biliary structures, which can present as single or multiple dilatations and can appear as both intra- and extrahepatic anomalies. The most widespread classification of CCs is the Todani classification, but there have been numerous reports of cysts that do not fall into any of the types described. We present such a case—a male patient 36 years of age who underwent preoperative CT, MRCP, and ERCP, which mistakenly indicated a type II Todani CC, and intraoperatively was found to be located at the confluence of the hepatic ducts and encompassed the origin of the common bile duct. Complete resection of the cyst and the proximal segment of the common bile duct was performed, and reconstruction was carried out by Roux-en-Y double-tutorized hepaticojejunostomy. Considering the risk of malignant transformation, the frequent preoperative misdiagnosis, as well as the technically challenging surgery required in such cases, we advocate for a revision of the classification and raise awareness of the need for guidelines regarding the proper short-term and long-term management of this disease to ensure adequate quality of life and disease-free survival for patients.

Todani Type I Common Bile Duct Cyst in an Adult Patient: Clinical Case and Literature Review

“…La etiología del quiste de colédoco permanece incierta, aunque la hipótesis más aceptada es la propuesta por Babbitt en 1969 (7) , que se fundamenta en la unión anómala del conducto pancreático y el colédoco, haciendo que se conecten a 1,5-4 cm del esfínter de Oddi, creando un "conducto común" que comunica el jugo pancreático y la bilis; la diferencia de presiones da como resultado el desarrollo de reflujo pancreatobiliar. La posterior activación de enzimas pancreáticas genera inflamación y adelgazamiento de las paredes del colédoco, lo que lleva a la dilatación del mismo; a favor de esto, se ha reportado un nivel de amilasa en la bilis mayor en los pacientes con quiste de colédoco en comparación con pacientes sanos (8,9) . La teoría de Babbitt explica el 50%-80% de los casos, ya que no todos los pacientes que presentan este conducto común largo tienen quiste de colédoco; así mismo, pacientes diagnosticados con quiste de colédoco no presentan este conducto común (10) .…”