title: Peripancreatic collections in acute pancreatitis: correlation between computerized tomography and operative findings.
abstract: OBJECTIVE
  To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.
  
  
  METHODS
  Twenty five patients with peripancreatic collections on CECT and who underwent operative intervention for severe acute pancreatitis were retrospectively studied. The collections were classified into (1) necrosis without frank pus; (2) necrosis with pus; and (3) fluid without necrosis. A blinded radiologist assessed the preoperative CTs of each patient for necrosis and peripancreatic fluid collections. Peripancreatic collections were described in terms of volume, location, number, heterogeneity, fluid attenuation, wall perceptibility, wall enhancement, presence of extraluminal gas, and vascular compromise.
  
  
  RESULTS
  Fifty-four collections were identified at operation, of which 45 (83%) were identified on CECT. Of these, 25/26 (96%) had necrosis without pus, 16/19 (84%) had necrosis with pus, and 4/9 (44%) had fluid without necrosis. Among the study characteristics, fluid heterogeneity was seen in a greater proportion of collections in the group with necrosis and pus, compared to the other two groups (94% vs 48% and 25%, P = 0.002 and 0.003, respectively). Among the wall characteristics, irregularity was seen in a greater proportion of collections in the groups with necrosis with and without pus, when compared to the group with fluid without necrosis (88% and 71% vs 25%, P = 0.06 and P < 0.01, respectively). The combination of heterogeneity and presence of extraluminal gas had a specificity and positive likelihood ratio of 92% and 5.9, respectively, in detecting pus.
  
  
  CONCLUSIONS
  Most of the peripancreatic collections seen on CECT in patients with severe acute pancreatitis who require operative intervention contain necrotic tissue. CECT has a somewhat limited role in differentiating the different types of collections.
authors.affiliation: Miles and Shirley Fiterman Center for Digestive Diseases, 200 First Street SW, Rochester, MN 55905, USA. vege.santhi@mayo.edu
authors.forename: Santhi Swaroop
authors.initials: SS
authors.lastname: Vege
authors.forename: Joel G
authors.initials: JG
authors.lastname: Fletcher
authors.forename: Rupjyoti
authors.initials: R
authors.lastname: Talukdar
authors.forename: Michael G
authors.initials: MG
authors.lastname: Sarr
mesh_terms: D000208:Acute Disease; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D010195:Pancreatitis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D011856:Radiographic Image Enhancement; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media
references.citation: AJR Am J Roentgenol. 1991 Jan;156(1):93-5
references.pmid: 1898576
references.citation: Gut. 1986 Sep;27(9):1035-42
references.pmid: 3530895
references.citation: Am J Gastroenterol. 2006 Oct;101(10):2379-400
references.pmid: 17032204
references.citation: Am Surg. 1990 Dec;56(12):796-9
references.pmid: 2268109
references.citation: Rom J Gastroenterol. 2005 Jun;14(2):129-34
references.pmid: 15990931
references.citation: World J Surg. 1985 Dec;9(6):972-9
references.pmid: 4082619
references.citation: AJR Am J Roentgenol. 2008 Mar;190(3):643-9
references.pmid: 18287434
references.citation: Radiology. 1997 Jun;203(3):773-8
references.pmid: 9169703
references.citation: Radiology. 2002 Jun;223(3):603-13
references.pmid: 12034923
references.citation: Gastrointest Radiol. 1984;9(1):27-30
references.pmid: 6724235