Monitoring fibrosis of the pancreatic remnant after a pancreaticoduodenectomy with dynamic MRI

Abstract

Background: The time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging closely reflects the histological degree of pancreatic fibrosis.

Materials and methods: Seventy-six patients who had undergone a pancreatic TIC analysis prior to receiving a pancreaticoduodenectomy for various reasons were subjected to a yearly monitoring with pancreatic TIC for the pancreatic remnants. The pancreatic TIC profiles were classified into 3 types: type I, indicating a normal pancreas without fibrosis; and types II and III indicating fibrotic pancreas.

Results: The preoperative pancreatic TICs were type-I in 51 patients, type-II in 20, and type-III in 5, and the corresponding pancreatic fibrosis ratios were proved histologically to be 4.1%, 13.3%, and 21.2%, respectively. The mean postoperative follow-up period was 40.2 mo. A type-I changed to type-II in 16 patients, by 32.3 mo after surgery. In these patients, the exocrine remnant pancreatic function was preserved at the time of TIC conversion, but it significantly deteriorated thereafter. Pancreatic anastomotic leakage was found to be a significant risk factor predisposing a patient to undergo postoperative TIC conversion. In contrast, a preoperative type-II or III showed a postoperative conversion to type-I or II in 6 patients. In this group, the exocrine pancreatic function was noted to show a good recovery. In 35 patients who had a type-I TIC throughout the study, the remnant pancreatic function was well maintained.

Conclusions: Pancreatic TIC analysis has the ability to detect an early fibrotic change that precedes a functional deterioration of the pancreatic remnant after a pancreaticoduodenectomy. Following a pancreaticoduodenectomy, some patients show an improvement in pancreatic fibrosis, but they may also experience remnant pancreatic fibrosis when pancreatic anastomotic leakage occurs after surgery.