Computed high-b-value high-resolution DWI improves solid lesion detection in IPMN of the pancreas

Objectives To examine the effect of high- b -value computed diffusion-weighted imaging (cDWI) on solid lesion detection and classification in pancreatic intraductal papillary mucinous neoplasm (IPMN), using endoscopic ultrasound (EUS) and histopathology as a standard of reference. Methods Eighty-two patients with known or suspected IPMN were retrospectively enrolled. Computed high- b -value images at b = 1000 s/mm 2 were calculated from standard ( b = 0, 50, 300, and 600 s/mm 2 ) DWI images for conventional full field-of-view (fFOV, 3 × 3 × 4 mm 3 voxel size) DWI. A subset of 39 patients received additional high-resolution reduced-field-of-view (rFOV, 2.5 × 2.5 × 3 mm 3 voxel size) DWI. In this cohort, rFOV cDWI was compared against fFOV cDWI additionally. Two experienced radiologists evaluated (Likert scale 1–4) image quality (overall image quality, lesion detection and delineation, fluid suppression within the lesion). In addition, quantitative image parameters (apparent signal-to-noise ratio (aSNR), apparent contrast-to-noise ratio (aCNR), contrast ratio (CR)) were assessed. Diagnostic confidence regarding the presence/absence of diffusion - restricted solid nodules was assessed in an additional reader study. Results High- b -value cDWI at b = 1000 s/mm 2 outperformed acquired DWI at b = 600 s/mm 2 regarding lesion detection, fluid suppression, aCNR, CR, and lesion classification ( p =