Inter-study reproducibility of arterial spin labelling magnetic resonance imaging for measurement of renal perfusion in healthy volunteers at 3 Tesla

• Published in: BMC nephrology Vol. 15; no. 1; p. 23
• Main Authors: Gillis, Keith A, McComb, Christie, Foster, John E, Taylor, Alison H M, Patel, Rajan K, Morris, Scott T W, Jardine, Alan G, Schneider, Markus P, Roditi, Giles H, Delles, Christian, Mark, Patrick B
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 31-01-2014; BioMed Central
• Subjects: Adult; Blood Flow Velocity - physiology; Clinical medicine; Contrast agents; Epidemiology; Female; Humans; Hypertension; Image Interpretation, Computer-Assisted - methods; Kidney - blood supply; Kidney - physiology; Kidney diseases; Labeling; Magnetic Resonance Angiography - methods; Magnetic resonance imaging; Male; Measurement; Medical research; Medicine, Experimental; Methods; Nephrology; NMR; Nuclear magnetic resonance; Reference Values; Renal Artery - physiology; Renal Circulation - physiology; Reproducibility of Results; Sensitivity and Specificity; Spin Labels; Studies; Transplants & implants
• ISSN: 1471-2369; 1471-2369
• DOI: 10.1186/1471-2369-15-23

Measurement of renal perfusion is a crucial part of measuring kidney function. Arterial spin labelling magnetic resonance imaging (ASL MRI) is a non-invasive method of measuring renal perfusion using magnetised blood as endogenous contrast. We studied the reproducibility of ASL MRI in normal volunteers.
ASL MRI was performed in healthy volunteers on 2 occasions using a 3.0 Tesla MRI scanner with flow-sensitive alternating inversion recovery (FAIR) perfusion preparation with a steady state free precession (True-FISP) pulse sequence. Kidney volume was measured from the scanned images. Routine serum and urine biochemistry were measured prior to MRI scanning.
12 volunteers were recruited yielding 24 kidneys, with a mean participant age of 44.1 ± 14.6 years, blood pressure of 136/82 mmHg and chronic kidney disease epidemiology formula estimated glomerular filtration rate (CKD EPI eGFR) of 98.3 ± 15.1 ml/min/1.73 m2. Mean kidney volumes measured using the ellipsoid formula and voxel count method were 123.5 ± 25.5 cm3, and 156.7 ± 28.9 cm3 respectively. Mean kidney perfusion was 229 ± 41 ml/min/100 g and mean cortical perfusion was 327 ± 63 ml/min/100 g, with no significant differences between ASL MRIs. Mean absolute kidney perfusion calculated from kidney volume measured during the scan was 373 ± 71 ml/min. Bland Altman plots were constructed of the cortical and whole kidney perfusion measurements made at ASL MRIs 1 and 2. These showed good agreement between measurements, with a random distribution of means plotted against differences observed. The intra class correlation for cortical perfusion was 0.85, whilst the within subject coefficient of variance was 9.2%. The intra class correlation for whole kidney perfusion was 0.86, whilst the within subject coefficient of variance was 7.1%.
ASL MRI at 3.0 Tesla provides a repeatable method of measuring renal perfusion in healthy subjects without the need for administration of exogenous compounds. We have established normal values for renal perfusion using ASL MRI in a cohort of healthy volunteers.