The prognostic value of fat necrosis deposits on CT imaging in acute pancreatitis

Background/aim: Investigate the prognostic value of the fat necrosis deposit (FND) pattern in acute pancreatitis. Materials and methods: The contrast-enhanced computed tomography (CT) images of 35 necrotizing pancreatitis (NP) and 51 edematous pancreatitis (EP) cases were included in our retrospective study. Computed tomography severity index (CTSI) and Ranson scores were calculated. Images were evaluated for FND, complications (infection/ hemorrhage), walled-off necrosis (WON), and venous thrombosis (VT). We developed a new grading system called fat necrosis deposit-CTSI (FND-CTSI), which was the sum of FND and CTSI scores. The relationship between grading systems and mortality, length of hospital-intensive care unit stay, surgical and percutaneous interventions were evaluated. Results: FND-CTSI scores were significantly higher in NP than EP (P < 0.001). FND-CTSI demonstrated a significant correlation with CTSI (r:0.91, P < 0.001) and Ranson score (r:0.24, P = 0.025). CTSI was significantly higher in only mass form amongst the FND groups (P < 0.001). There was a significant difference in WON, complications, and mortality between FND groups (P < 0.05). CTSI and FND-CTSI scores were both significantly associated with WON, VT, surgical intervention, mortality (P < 0.001), and the presence of complications (P = 0.013 and P = 0.007, respectively). FND-CTSI was also significantly associated with percutaneous intervention (P = 0.019), while CTSI was not (P > 0.05). According to ROC analysis, AUC values of FND-CTSI were higher than CTSI for the detection of WON, complications, mortality, and percutaneous intervention (P < 0.05). FND-CTSI showed a highly significant correlation with the length of hospital and intensive care unit stays (P < 0.001). Conclusion: FND-CTSI can be used in acute pancreatitis grading and considered as a prognostic factor.