Magnetic resonance cholangiopancreatography evaluation of intrahepatic and extrahepatic bile duct variations in Turkish population

Yıl 2024, Cilt: 29 Sayı: 3, 233 - 241, 23.09.2024

İsmail Kartal , Nesrin Atci , Sinem Karazincir

https://doi.org/10.21673/anadoluklin.1339149

Öz

Aim: Bile ducts are formations that have many variations other than their known anatomical distribution and have tight connections with the adjacent structures. Anatomical variations that can be seen in intra or extrahepatic bile ducts might cause various problems in operations like laparoscopic surgery and liver transplantation. Knowing these anatomical variations will be useful for lowering the operational injury risk. This study aimed to reveal the prevalence of common and rare patterns of biliary tree anatomy in our society using magnetic resonance cholangiopancreatography (MRCP).

Methods: In this study, MRCP images of 663 patients taken between January 1, 2012 and January 1, 2016 were evaluated retrospectively. MRCP scans were performed on a 1.5 Tesla magnetic resonance unit by using phased-array coil. Heavily T2 weighted images were obtained with single-shot fast spin echo technique.

Results: Anatomical variations were detected in 224 (33.8%) of the patients evaluated. Variations were evaluated in four main perspectives. Those were grouped respectively as intrahepatic bile duct variations, extrahepatic bile duct duplications, cystic duct variations and other variations. The most common variation in the intrahepatic bile duct level was detected as trifurcation (9.4%). Extrahepatic bile duct duplication which is a rarely reported variation in the literature was present in 3 of our cases (0.5%). The most common variation in the cystic duct level was long cystic duct (distal connection) and the most seen other variations were pancreas divisum and vascular compression to the common hepatic duct.

Conclusion: Bile ducts can be visualized noninvasively in a very short period without any exposure to ionizing radiation, use of contrast material and without any complication with MRCP scan. In the patients who are planned to have pancreatobiliary invasive procedure or operation, detecting and stating the bile duct variations with MRCP scan will prevent the possible iatrogenic traumas.

Anahtar Kelimeler

Anatomical variation, bile ducts, magnetic resonance cholangiopancreatography, magnetic resonance imaging

Türk nüfusunda intrahepatik ve ekstrahepatik safra kanalı varyasyonlarının manyetik rezonans kolanjiyopankreatografi değerlendirilmesi

Öz

Amaç: Safra kanalları bilinen anatomik dağılımları dışında birçok varyasyona sahip, komşu yapılarla sıkı bağlantıları olan oluşumlardır. İntrahepatik veya ekstrahepatik safra yollarında görülebilen anatomik varyasyonlar, laparoskopik cerrahi ve karaciğer nakli gibi operasyonlarda çeşitli sorunlara neden olabilir. Bu anatomik varyasyonları bilmek, operasyon yaralanma riskini azaltmak için faydalı olacaktır. Bu çalışmada toplumumuzda safra ağacı anatomisinin sık ve nadir görülen paternlerinin yaygınlığını manyetik rezonans kolanjiyopankreatografide (MRKP) ortaya çıkarmak amaçlanmıştır.

Yöntemler: Bu çalışmada, 1 Ocak 2012 ile 1 Ocak 2016 yılları arasında çekilen 663 hastanın MRKP görüntüleri retrospektif olarak değerlendirildi. MRKP taramaları, faz dizili koil kullanılarak 1.5 Tesla manyetik rezonans ünitesinde gerçekleştirildi. Single-shot fast spin echo yöntemi ile bT2 ağırlıklı görüntüler değerlendirildi.

Bulgular: Değerlendirilen hastaların 224'ünde (%33,8) anatomik varyasyon saptandı. Varyasyonlar dört ana perspektifte değerlendirildi. Bunlar sırasıyla intrahepatik safra kanalı varyasyonları, ekstrahepatik safra kanalı duplikasyonları, sistik kanal varyasyonları ve diğer varyasyonlar olarak gruplandırıldı. İntrahepatik safra kanalı seviyesindeki en yaygın varyasyon trifurkasyon (%9,4) olarak saptandı. Literatürde nadiren bildirilen bir varyasyon olan ekstrahepatik safra kanalı duplikasyonu olgularımızın 3'ünde (%0,5) mevcuttu. Sistik kanal düzeyindeki en yaygın varyasyon uzun sistik kanal (distal bağlantı) idi ve en sık görülen diğer varyasyonlar pankreas divizum ve ortak hepatik kanala vasküler bası idi.

Sonuç: MRKP ile safra kanalları iyonizan radyasyona maruz kalmadan, kontrast madde kullanmadan ve herhangi bir komplikasyon olmaksızın çok kısa sürede noninvaziv olarak görüntülenebilmektedir. Pankreatobiliyer invaziv girişim veya operasyon planlanan hastalarda MRKP ile safra kanalı varyasyonlarının saptanması ve belirtilmesi olası iatrojenik travmaların önüne geçecektir.

Anahtar Kelimeler

Anatomik varyasyon, safra kanalları, manyetik rezonans kolanjiopankreatografi, manyetik rezonans görüntüleme

Kaynakça

• Gazelle GS, Lee MJ, Mueller PR. Cholangiographic segmental anatomy of the liver. Radiographics. 1994;14(5):1005-13.
• Mortele KJ, Ros PR. Anatomic variants of the biliary tree: MR cholangiographic findings and clinical applications. AJR Am J Roentgenol. 2001;177(2):389-94.
• Turner MA, Fulcher AS. The cystic duct: normal anatomy and disease processes. Radiographics. 2001;21(1):3-294.
• Ober EA, Lemaigre FP. Development of the liver: Insights into organ and tissue morphogenesis. J Hepatol. 2018;68(5):1049-62.
• Dohke M, Watanabe Y, Okumura A, et al. Anomalies and anatomic variants of the biliary tree revealed by MR cholangiopancreatography. AJR Am J Roentgenol. 1999;173(5):1251-4.
• Taourel P, Bret PM, Reinhold C, Barkun AN, Atri M. Anatomic variants of the biliary tree: diagnosis with MR cholangiopancreatography. Radiology. 1996;199(2):521-7.
• Moeini A, Haber PK, Sia D. Cell of origin in biliary tract cancers and clinical implications. JHEP Rep. 2021;3(2):100226.
• Berci G. Biliary ductal anatomy and anomalies. The role of intraoperative cholangiography during laparoscopic cholecystectomy. Surg Clin North Am. 1992;72(5):1069-75.
• Düşünceli E, Erden A, Erden I. Biliyer sistemin anatomik varyasyonlari: MRKP bulgulari [Anatomic variations of the bile ducts: MRCP findings]. Tani Girisim Radyol. 2004;10(4):296-303.
• Choi E, Byun JH, Park BJ, Lee MG. Duplication of the extrahepatic bile duct with abnormal union of the pancreaticobiliary ductal system revealed by MR cholangiopancreatography. Br J Radiol. 2007;80(955):e150-4.
• Kosar I, Ataseven H, Yönem O, et al. A new variant of bile duct duplication with coexistence of distal cholangiocarcinoma. Nat Rev Gastroenterol Hepatol. 2010;7(9):527-30.
• Huang TL, Cheng YF, Chen CL, Chen TY, Lee TY. Variants of the bile ducts: clinical application in the potential donor of living-related hepatic transplantation. Transplant Proc. 1996;28(3):1669-70.
• Smith T, Rana RS, Missiaen P, et al. High bat (Chiroptera) diversity in the Early Eocene of India. Naturwissenschaften. 2007;94(12):1003-9.
• Nayman A, Özbek O, Erol S, Karakuş H, Kaya HE. Magnetic resonance cholangiopancreatography evaluation of intrahepatic bile duct variations with updated classification. Diagn Interv Radiol. 2016;22(6):489-94.
• Yoshida J, Chijiiwa K, Yamaguchi K, Yokohata K, Tanaka M. Practical classification of the branching types of the biliary tree: an analysis of 1,094 consecutive direct cholangiograms. J Am Coll Surg. 1996;182(1):37-40.
• Halefoglu AM. Magnetic resonance cholangiopancreatography: a useful tool in the evaluation of pancreatic and biliary disorders. World J Gastroenterol. 2007;13(18):2529-34.
• Swain B, Sahoo RK, Sen KK, G MK, Parihar SS, Dubey R. Evaluation of intrahepatic and extrahepatic biliary tree anatomy and its variation by magnetic resonance cholangiopancreatography in Odisha population: a retrospective study. Anat Cell Biol. 2020;53(1):8-14.
• Hussein AM, Botros SM, Abdelhafez AH, Mahfouz M. Biliary tree variations as viewed by intra-operative cholangiography - comparing Egyptian versus international data. Egypt J Radiol Nucl Med. 2016;47(4):1283–92.
• Sarawagi R, Sundar S, Gupta SK, Raghuwanshi S. Anatomical variations of cystic ducts in magnetic resonance cholangiopancreatography and clinical implications. Radiol Res Pract. 2016;2016:3021484.