MRI Imaging Of Acute Pancreatitis: Retroperitoneal Interfascial Planes Involvement And The Different Predictive Value Of Three Scoring Systems

Objective: To study MRI findings of acute pancreatitis（AP）involvedthe retroperitoneal interfascial planes, and analyze the correlations ofinterfascial planes involvement with MR severity index（MRSI) and Acutephysiology and chronic health evaluation（APACHE Ⅱ) scoring system.Materials and Methods:316patients with AP confirmed by clinical andlaboratory tests between November2011and August2013wereretrospectively analyzed. To observe the extension and way of AP spreadalong the retroperitoneal interfascial plane, and graded it:Grade0,retroperitoneal interfascial planes and perirenal space was normal (recordedas0points); Grade1, inflammation confined to the anterior pararenal space orretromesenteric plane(recorded as1points); Grade2, inflammation spreadinginto the lateroconal plane, retrorenal plane or perirenal space (recorded as2points); Grade3, inflammation spreading into the combined interfascialplane(recorded as3points); Grade4, inflammation spreading into the thesubfascial plane(recorded as4points); Grade5, inflammation intruding intothe posterior pararenal space(recorded as5points).The correlations ofinterfascial planes involvement with MRSI and APACHE Ⅱwere analyzed.Results: Of the316patients with AP,293patients (92.7%) hadinterfascial planes involvement,which showed that the interfascial planesedema, thickening and effusion. There were60patients(19%) in Grade1,105patients（33.2%）in Grade2,78patients（24.7%）in Grade3,25patients（7.9%）in Grade4,25patients（7.9%）in Grade5, respectively. The interfascial planes involvement was strongly correlated with the MRSI score(r=0.703, P=0.000) and was slightly correlated with the APACHE-II score(r=0.291, P=0.000).Conclusion: The interfascial planes involvement is a common MRimage of acute pancreatitis,which may be a supplementary indicator indetermining the severity of AP. Objective: To study the ability of the extrapancreatic inflammation onMR(EPIM), MR severity index(MRSI) and Acute physiology and chronichealth evaluation Ⅱ(APACHEⅡ) scoring systerm to evaluate the severity ofacute pancreatitis. To discuss the merit and demerit of the three systerms andprovide the basis for the pervasive application of the systerms in clinical.Materials and Methods:260patients with AP confirmed by clinicaland laboratory tests between January2011and December2012wereretrospectively analyzed. EPIM consulted the standard of the extrapancreaticinflammation on CT (EPIC).EPIM、MRSI、APACHEⅡ scoring system wereused to grade the260AP patients.The ROC curve was utilized to analyze andevaluate the value of the three scoring systems in diagnosing severe AP(SAP),local complications and organ failure. Results：Of the260patients with AP,132patients (50.7%) had severe AP,97patients (37.3%) had local complications and34patients (13.1%) hadorgan failure. The grading scores of three scoring systems all had significantdifference in mild and severe acute pancreatitis, with or without localcomplications and with or without organ failure. The area under receiveroperating characteristic curve (AUC) of EPIM, MRSI and APACHEⅡscoring system to predict SAP were0.807,0.869and0.768, respectively(When MRSI compared with the other two AUC， the difference hadstatistically significant).The AUC of EPIM, MRSI and APACHE II scoringsystem to predict local complications were0.832,0.932and0.690,respectively (When compared between every two AUC，the difference hadstatistically significant). The AUC of EPIM, MRSI and APACHEII scoringsystem to predict organ failure were0.685,0.673and0.792, respectively(When APACHE II compared with the other two AUC，the difference hadstatistically significant).Conclusion: The grading scores of EPIM scoring system had significantdifference in mild and severe acute pancreatitis, with or without localcomplications and with or without organ failure. EPIM scoring system hadcertain function for the early prediction of the severity of AP. All the threescoring systerms can well predict SAP, local complications and organ failure.And MRSI scoring system was superior to the other in predicting SAP andlocal complications; APACHEⅡ scoring system was superior to the other inpredicting organ failure.