Splenic and perisplenic involvement in acute pancreatitis: Determination of prevalence and morphologic helical CT features

Purpose: The purpose of this work was to determine the prevalence and morph ologic helical CT features of splenic and perisplenic involvement in patien ts with acute pancreatic inflammatory disease in correlation with the sever ity of the pancreatitis. Method: One hundred fifty-nine contrast-enhanced helical CT scans of 100 co nsecutive patients with acute pancreatitis were reviewed retrospectively an d independently by three observers. CT scans were scored using the CT sever ity index (CTSI): Pancreatitis was graded as mild (0-2 points), moderate (3 -6 points), and severe (7-10 points). Interobserver agreement for both the CTSI and the presence of splenic and perisplenic involvement was calculated (kappa statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using the Fisher exact test. Results: The severity of pancreatitis was graded as mild (n = 59 scans), mo derate (n = 82 scans). and severe (n = 18 scans). Splenic and perisplenic a bnormalities detected included perisplenic inflammatory fluid collections ( 95 scans, 58 patients), narrowing of the splenic vein (35 scans, 25 patient s), splenic vein thrombosis (31 scans. 19 patients), splenic infarction (10 scans, 7 patients), and subcapsular hemorrhage (2 scans, 2 patients). No c ases of splenic artery pseudoaneurysm formation, intrasplenic venous thromb osis, intrasplenic pseudocysts, or abscesses were detected. The interobserv er agreement range for scoring the degree of pancreatitis and the overall p resence of abnormalities was 75.5-79.2 and 71.7-100%, respectively. A stati stically significant difference between the presence of abnormalities and t he severity of pancreatitis was observed (p < 0.001). Conclusion: Splenic vein thrombosis (19%) and splenic infarction (7%) are r elatively common CT findings in association with acute pancreatitis. The CT SI proves to be accurate in predicting these complications as there is a st atistically significant correlation between the prevalence of these complic ations and the severity of pancreatitis.