副肝管に胆囊管が合流する胆管走行異常を呈した胆囊炎に対して腹腔鏡下胆囊摘出術を施行した1例

Laparoscopic cholecystectomy for cholecystitis with biliary tract anomaly, joining the cystic duct and aberrant hepatic duct

◆要旨：患者は58歳，男性．心窩部痛を主訴に当院を受診し，胆石性胆囊炎の診断にて腹腔鏡下胆囊摘出術を行うこととした．術前MRCPにて，独立分岐の後区域枝へ胆囊管が合流しており，術中は胆囊漿膜下層内層（SS-I）を意識して剝離を行い，後区域枝を確認した後に胆囊管を処理した．当院では2014年4月から2018年4月までに腹腔鏡下胆囊摘出術を77例施行した．全例にMRCPまたはDIC-CTを施行しており，胆囊管が後区域枝へ合流する症例は本症例のみであった．胆囊管が副肝管へ合流する走行異常は頻度が低く，SS-Iを意識した慎重な手術操作が必要である．また，胆囊頸部周囲の高度炎症が予想される症例では胆管損傷を回避するために，術前画像による胆管走行異常の把握が有用である．

　A 58-year-old man presented with epigastric discomfort, and was diagnosed as having gallstone cholecystitis. Conservative treatment with antibiotics was started and the surgery was planned after 2 months. Preoperative MRCP revealed the cystic duct draining into an aberrant right posterior hepatic duct. We performed laparoscopic cholecystectomy （Lap-C） and were able to separate the cystic duct after exposing the inner layer of the gallbladder subserosa （SS-I） and confirming the aberrant right posterior hepatic duct. Between April 2014 and April 2018, we have performed Lap-C in 77 patients. The cystic duct draining into the right posterior hepatic duct, as in this case, is unusual, and we need to carefully expose the SS-I so as to avoid mistaking between the hepatic duct and cystic duct. Especially in cases with severe inflammation, preoperative imaging examination is useful to avoid biliary tract injury.