Diagnostic Value of Pericholedochal Hypointense Ring Sign in MRI T2W Images in Cases of Pancreatic Ductal Adenocarcinoma.

Objective: To determine the value of hypointense pericholedocal ring sign in magnetic resonance imaging (MRI) T2W sequence images in the diagnosis of pancreatic ductal adenocarcinoma (PDA).

Study design: Retrospective observational study. Place and Duration of the Study: Department of Radiology, Bakirkoy Dr Sadi Konuk Training and Research Hospital, Istanbul, Turkiye, from January 2016 and March 2022.

Methodology: Retrospective analysis of MRI scans was performed on 70 patients with postoperative histopathological confirmation of a diagnosis of periampullary cancer. The patients' demographic information, the results of their histopathological examinations, and the findings of their MRIs were recorded. The results of the MRI were statistically analysed and compared between the PDA and the non-PDA groups.

Results: The study included 43 (61.4%) male and 27 (38.5%) female patients, with a mean age of 62.2 ± 8.4 years. The means of Wirsung diameter and tumour diameter were significantly higher in PDA group (p = 0.034, p = 0.010, respectively). A progressive contrast enhancement pattern of 95.3% was observed in PDA group, while 40.7% rapid contrast enhancement pattern was observed in the non-PDA group. Hypointense pericholedochal ring sign, observed in T2W sequences, was detected in 74.2% (n = 32) of the PDA group and 11.1% (n = 3) of the non-PDA group, and the findings were statistically significant (p <0.001).

Conclusion: Hypointense pericholedochal ring sign in axial T2W sequences in periampullary tumours is a complementary MRI finding in the distinction between the PDA and the non-PDA groups.

Key words: Magnetic resonance imaging, Pancreatic ductal adenocarcinoma, Periampullary tumours, Pericholedochal ring sign.