Accuracy of Blood Flow Values Determined by Arterial Spin Labeling: a Validation Study in Isolated Porcine Kidneys

Purpose: To validate the accuracy of quantitative blood flow values determined using pulsed arterial spin labeling (ASL) in the preserved and reperfused porcine kidney.

Materials And Methods: Ex vivo porcine kidneys were perfused with whole blood under physiological conditions, in particular including pulsatile flow. Total flow through the kidney was determined using an ultrasound flowmeter. ASL measurements at two different inversion times and four different flow rates in the range of 70-210 mL/100 mL*minute were performed. Absolute values of blood flow and arterial transit times were determined in the kidney cortex.

Results: The quantitative values were in good agreement with the reference values obtained after calibration of the total flow. The greatest difference observed was 13%.

Conclusion: Isolated organ hemoperfusion allows validating perfusion imaging techniques. The experimental setup enables long-term radiotherapeutic or toxicological studies using noninvasive ASL to monitor blood flow quantitatively.