title: Non-Contrast Renal Magnetic Resonance Imaging to Assess Perfusion and Corticomedullary Differentiation in Health and Chronic Kidney Disease.
abstract: OBJECTIVE
  Arterial spin labelling (ASL) MRI measures perfusion without administration of contrast agent. While ASL has been validated in animals and healthy volunteers (HVs), application to chronic kidney disease (CKD) has been limited. We investigated the utility of ASL MRI in patients with CKD.
  
  
  METHODS
  We studied renal perfusion in 24 HVs and 17 patients with CKD (age 22-77 years, 40% male) using ASL MRI at 3.0T. Kidney function was determined using estimated glomerular filtration rate (eGFR). T1 relaxation time was measured using modified look-locker inversion and xFB02;ow-sensitive alternating inversion recovery true-fast imaging and steady precession was performed to measure cortical and whole kidney perfusion.
  
  
  RESULTS
  T1 was higher in CKD within cortex and whole kidney, and there was association between T1 time and eGFR. No association was seen between kidney size and volume and either T1, or ASL perfusion. Perfusion was lower in CKD in cortex (136 ± 37 vs. 279 ± 69 ml/min/100 g; p < 0.001) and whole kidney (146 ± 24 vs. 221 ± 38 ml/min/100 g; p < 0.001). There was significant, negative, association between T1 longitudinal relaxation time and ASL perfusion in both the cortex (r = -0.75, p < 0.001) and whole kidney (r = -0.50, p < 0.001). There was correlation between eGFR and both cortical (r = 0.73, p < 0.01) and whole kidney (r = 0.69, p < 0.01) perfusion.
  
  
  CONCLUSIONS
  Significant differences in renal structure and function were demonstrated using ASL MRI. T1 may be representative of structural changes associated with CKD; however, further investigation is required into the pathological correlates of reduced ASL perfusion and increased T1 time in CKD.
authors.affiliation: Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Gillis
authors.forename: Christie
authors.initials: C
authors.lastname: McComb
authors.forename: Rajan K
authors.initials: RK
authors.lastname: Patel
authors.forename: Kathryn K
authors.initials: KK
authors.lastname: Stevens
authors.forename: Markus P
authors.initials: MP
authors.lastname: Schneider
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Radjenovic
authors.forename: Scott T W
authors.initials: ST
authors.lastname: Morris
authors.forename: Giles H
authors.initials: GH
authors.lastname: Roditi
authors.forename: Christian
authors.initials: C
authors.lastname: Delles
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Mark
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007672:Kidney Cortex / Q000000981:diagnostic imaging* / Q000502:physiology / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000000981:diagnostic imaging*; D007679:Kidney Medulla / Q000000981:diagnostic imaging* / Q000502:physiology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055815:Young Adult