title: Comparison of readout-segmented and conventional single-shot for echo-planar diffusion-weighted imaging in the assessment of kidney interstitial fibrosis.
abstract: To compare readout-segmented echo-planar imaging (EPI) (RESOLVE) to single-shot EPI (ss-EPI) diffusion-weighted imaging (DWI) for the assessment of renal interstitial fibrosis.
  
  
  
  A phantom, eight healthy volunteers (under 30 years to avoid age-fibrosis related) and 27 chronic kidney disease (CKD) patients (scheduled for kidney biopsy) were scanned (at 3T) with ss-EPI and 5-shot RESOLVE DWI (resolution: 2 × 2 × 5 mm3, 10 b-values). The cortico-medullary difference for each DW parameter from a monoexponential fit (ΔADC) or, segmented biexponential fit (ΔD, ΔD*, ΔFp) were compared between both sequences. A fibrosis threshold of 40% was defined to separate all 35 subjects into low and high fibrosis groups. The linear relationship between DW parameters and percentage fibrosis (up to 80%) from Masson trichrome was assessed with the Pearson product-moment correlation coefficient. Fisher Z-transform was used for R2correlation comparison.
  
  
  
  A coefficient of variation between ADCs of 3% was measured between both sequences in the phantom. In healthy volunteers, no significant difference was measured for all DW parameters. Both sequences separated low to high level of fibrosis with a significant decrease of ΔADC (RESOLVE P = 3.1 × 10-6, ss-EPI P = 0.003) and ΔD (RESOLVE P = 8.2 × 10-5, ss-EPI P = 0.02) in the high level of fibrosis. However, RESOLVE ΔADC had a stronger negative correlation (P = 0.04 for R2comparison) with fibrosis than ss-EPI ΔADC (RESOLVE R2= 0.65, P = 5.9 × 10-9, ss-EPI R2= 0.29, P = 8.9 × 10-4). ΔD (RESOLVE) was correlated (moderately) with fibrosis (R2= 0.29, P = 9.2 × 10-4); however, ΔD* and ΔFpdid not show, in our population, a significant correlation with interstitial fibrosis (0.01 < R2< 0.08).
  
  
  
  ΔADC derived from both sequences correlated with fibrosis. ΔADC from RESOLVE showed better correlation with fibrosis than ΔADC from ss-EPI and therefore has potential to monitor CKD.
  
  
  
  1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1631-1640.
authors.affiliation: Division of Radiology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Iris
authors.initials: I
authors.lastname: Friedli
authors.affiliation: Division of Radiology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Lindsey Alexandra
authors.initials: LA
authors.lastname: Crowe
authors.affiliation: Division of Radiology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: de Perrot
authors.affiliation: Division of Nephrology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Lena
authors.initials: L
authors.lastname: Berchtold
authors.affiliation: Division of Nephrology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Martin
authors.affiliation: Division of Nephrology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: de Seigneux
authors.affiliation: Division of Radiology, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Vallée
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D005355:Fibrosis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D015203:Reproducibility of Results
keywords: RESOLVE; diffusion-weighted imaging; renal interstitial fibrosis; single-shot echo-planar imaging