Analysis of anatomical variations of the Cystic Duct in Magnetic Resonance Cholangiopancreatography  

Abstract

Background and objectives- Anatomical variants of the cystic duct (CD) are important be identified and described in the radiological report. This facilitates proper interpretation of the pathological process related to the biliary tree. Also, prior information is important before surgical, percutaneous and endoscopic interventional procedures related to the biliary tree, to avoid inadvertent complications and for successful outcomes. Magnetic Resonance Cholangiopancreatography (MRCP)is the best non-invasive imaging modality in detecting anatomy of the non-dilated cystic duct. This study was carried out to demonstrate imaging appearance of the cystic duct and its anatomical variants detected on MRCP and to document their prevalence in the study group. Methods- This is a single centre retrospective cross-sectional study including all consecutive patients who underwent MRCP form May 2020 to May 2021 at the neurosurgical MRI unit at National Hospital of Sri Lanka. Patients who had undergone cholecystectomies and images with poor quality were excluded.Results- Total 180 MRCP studies were analysed. Normally inserting CD to the lateral aspect of the Common Hepatic Duct (CHD) was observed in 127cases out of 180 (70.5%). 10(5.5%) demonstrated high inserting CD.12(6.6%) cases demonstrated low inserting CD.3(1.6%) had short CD. Parallel course of CD was noted in 12(6.6%). Low and medially inserting CD was present in 4(2.2%) cases. Anterior insertion was demonstrated in 5(2.7%) cases, and posterior insertion was demonstrated in 7(3.8%). Conclusion- Anatomical variants of the CD observed in our study group were comparable to reported frequencies, however posterior insertion was lesser than that found in literature.