title: IVIM DW-MRI of autoimmune pancreatitis: therapy monitoring and differentiation from pancreatic cancer.
abstract: OBJECTIVE
  To evaluate IVIM DW-MRI for changes in IVIM-derived parameters during steroid treatment of autoimmune pancreatitis (AIP) and for the differentiation from pancreatic cancer (PC).
  
  
  METHODS
  Fifteen AIP-patients, 11 healthy patients and 20 PC-patients were examined with DWI-MRI using eight b-values (50, 100, 150, 200, 300, 400, 600, 800). 12 AIP-patients underwent follow-up examinations during treatment. IVIM-parameters and ADC800-values were tested for significant differences and an ROC analysis was performed.
  
  
  RESULTS
  The perfusion fraction f was significantly lower in patients with AIP at the time of diagnosis (10.5 ± 4.3 %) than in patients without AIP (20.7 ± 4.3 %). In AIP follow-up, f increased significantly to 17.1 ± 7.0 % in the first and 21.0 ± 4.1 % in the second follow up. In PC, the f-values were lower (8.2 ± 4.0 %, n.s.) compared to initial AIP and were significantly lower compared to first and second follow-up examination. In the ROC-analysis AUC-values for f were 0.63, 0.88 and 0.98 for differentiation of PC from initial, first and second follow up AIP-examination.
  
  
  CONCLUSIONS
  The found differences in f between AIP, AIP during steroid treatment and pancreatic cancer suggest that IVIM-diffusion MRI could serve as imaging biomarker during treatment in AIP-patients and as a helpful tool for differentiation between PC and AIP.
  
  
  CONCLUSIONS
  • MRI is used for follow-up examinations during therapy in AIP-patients • IVIM-DWI-MRI offers parameters which reflect perfusion and true diffusion • IVIM-parameters are helpful for differentiation between AIP and pancreatic cancer • IVIM-parameters could serve as an imaging biomarker during steroid treatment.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany. miriam.klauss@med.uni-heidelberg.de.
authors.forename: Miriam
authors.initials: M
authors.lastname: Klauß
authors.affiliation: Department of Medical and Biological Informatics, DKFZ, Heidelberg, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Maier-Hein
authors.affiliation: Department of Surgery, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Tjaden
authors.affiliation: Department of Surgery, University of Heidelberg, Heidelberg, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Hackert
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Grenacher
authors.affiliation: Department of Radiology, University Hospital Basel, Basel, Switzerland.
authors.forename: Bram
authors.initials: B
authors.lastname: Stieltjes
mesh_terms: D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases / Q000000981:diagnostic imaging* / Q000628:therapy; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000000981:diagnostic imaging; D010190:Pancreatic Neoplasms; D010195:Pancreatitis / Q000000981:diagnostic imaging* / Q000628:therapy; D011446:Prospective Studies; D012372:ROC Curve; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Diffusion; Diffusion-weighted MRI; Magnetic Resonance Imaging; Pancreatic carcinoma; Pancreatitis