Prediction of Clinically-Relevant Postoperative Pancreatic Fistula after pancreatoduodenectomy based on Multi-frequency Magnetic Resonance Elastography.

Abstract

Background: Clinically relevant postoperative pancreatic fistula (CR-POPF) is the major complication of pancreatoduodenectomy, and the pancreatic texture is one of the potential affecting factors. Multi-frequency Magnetic Resonance Elastography (MRE) is a novel technique for measuring stiffness of tissue, while its value in predicting CR-POPF preoperatively has not been well-documented.

Method: Seventy patients who underwent multi-frequency MRE before pancreatoduodenectomy between July 2021 and April 2024 were retrospectively recruited into the study. The parameter of MRE, shear wave speed (c) and phase angle (φ), and clinical data were collected. Logistic regression and the receiver operating characteristic curve (ROC) analyses were used to assess the performance of multi-frequency MRE in predicting CR-POPF.

Results: CR-POPF was developed in 14 out of 70 patients (20%), all categorized as Grade B. CR-POPF group had significantly lower c (1.339±0.210m/s) and longer hospital stays (21±22days) than no CR-POPF group. The MRE parameters, c and φ were moderately correlated with pancreas stiffness (eta² for φ =0.189, eta² for c =0.106). Dilated major pancreatic duct (MPD) (≥3mm) and higher c were independently associated with lower risk of CR-POPF in univariant and multivariant analysis (odds ratio for c = 0.041, 95%CI: 0.002~0.879, odds ratio for dilated MPD: 0.129, 95%CI: 0.022~0.768). The AUC of the predictive model based on c and MPD diameter was 0.786, which was better than Fistula Risk Score (FRS) (AUC=0.587) and alternative Fistula Risk Score (a-FRS) (AUC=0.556) in our center, with DeLong's test p= 0.028 and p=0.002 respectively.

Conclusion: The MRE parameters were associated with pancreatic stiffness, and c was an independent predictor for CR-POPF after pancreatoduodenectomy.