Quantitative Evaluation of Acute Pancreatitis Based on Dual-Energy Computed Tomography.

Abstract

Objective: To evaluate the value of dual-energy computed tomography (DECT) parameters for the quantitative diagnosis of acute pancreatitis (AP) and classification of its severity.

Methods: Patients with AP underwent a plain CT scan and three contrast-enhanced DECT scans. We analyzed the group differences in iodine concentration (IC) and slope of the spectral Hounsfield unit curve (λHU) of the 3-phase enhanced scans (arterial, venous, and delayed phases).

Results: The study included 60 AP patients (38 males and 22 females; mean age: 47.43±13.47 y). On the basis of the CT severity index (CTSI), the patients were divided into 2 groups: group A (mild AP, n=26) and group B (moderate/severe AP, n=34). IC and λHU in the arterial and venous phases were all significantly higher in group A than in group B (P<0.001) and could effectively differentiate the 2 groups. The areas under the curve were 0.753 (95% CI: 0.624-0.855), 0.799 (95% CI: 0.676-0.892), 0.774 (95% CI: 0.647-0.872), and 0.842 (95% CI: 0.724-0.923) for IC at arterial and venous phases and λHU at arterial and venous phases, respectively. These parameters decreased with the increase of CTSI, showing significant negative correlations, with r were -0.512 (95% CI: -0.678 to -0.297), -0.492 (95% CI: -0.663 to -0.272), -0.552 (95% CI: -0.707 to -0.346), -0.569 (95% CI: -0.719 to -0.368) for IC at arterial and venous phases and λHU at arterial and venous phases, respectively (P<0.001).

Conclusions: DECT imaging can quantitatively analyze AP, and the IC and λHU can be used to distinguish mild and severe cases, adding functional information to the CT morphology to determine the severity and prognosis of the disease.