Variability of contrast enhancement of pancreas on computed tomography in patients with acute pancreatitis and isolated extrapancreatic necrosis

Background and study aim: To evaluate the variability in the enhancement of pancreas on computed tomography (CT) in patients with acute pancreatitis (AP) and isolated extrapancreatic necrosis (EPN) and to investigate whether it affects the extrapancreatic findings and patient outcomes.

Patients and methods: This retrospective study comprised of consecutive patients with isolated EPN evaluated between April 2017 and April 2019. A radiologist measured the pancreatic attenuation values (PAV) of head, body, and tail on a contrast enhanced CT. Using a cut-off PAV of 100HU, patients were divided into two groups. The extrapancreatic CT findings and outcome parameters were compared between the two groups.

Results: Thirty patients (mean age, 42.13 years, 17 males) with isolated EPN were evaluated. The mean PAV in the head, body, and tail was 83.13 HU (range, 59-161), 84.17 HU (range, 60-160), and 82.23 HU (range, 53-137). The overall mean PAV was 83.12 HU (range, 58-152). There were six patients with overall mean PAV≥100 HU. The group with PAV≥100 HU had a higher number of patients with infected necrosis (66.6% vs. 14.2%, P=0.018). PAV had a significant association with length of hospitalization (P=0.045).

Conclusion: There is significant variability in the pancreatic enhancement on CT among patients with AP and isolated EPN. Patients with PAV≥100 HU had a significantly longer hospital stay. This, however, may be related to a greater number of patients with infected necrosis in this group.

Keywords: acute pancreatitis, computed tomography, extrapancreatic necrosis, enhancement.