Short-term repeatability and postprandial effect assessment of liver perfusion quantification in healthy subjects using arterial spin labeling MRI

Abstract

Objectives: To assess the stability of liver perfusion quantification using arterial spin labeling MRI (ASL-MRI) in healthy subjects.

Materials and methods: The arterial and portal venous liver perfusion were measured with two pseudo-continuous ASL acquisitions at a 3.0-Tesla MRI system. To assess the short-term repeatability of ASL-MRI, twelve healthy subjects underwent three consecutive ASL examinations in the fasting state. Following meal ingestion, the postprandial liver perfusion was measured. Changes in liver perfusion measured by ASL before and after meal ingestion, and their correspondence with portal vein hemodynamic variations assessed by Doppler ultrasonography (US), were analyzed to evaluate the stability of ASL in detecting postprandial perfusion alterations.

Results: The arterial and portal venous liver perfusions in healthy volunteers under the fasting condition were 59.3 ± 17.8 and 237.6 ± 71.9 mL/100 g/min, respectively. Both the arterial and portal venous liver perfusion results demonstrated excellent short-term repeatability (ICCs, 0.97, 0.96; CVs, 6.43%, 6.17%). Furthermore, Bland-Altman plots indicated a high degree of consistency between every two pairs of the three measurements. Compared to the fasting state, the relative changes in postprandial portal venous perfusion measured by ASL-MRI demonstrated a moderate correlation (Pearson correlation coefficient r = 0.66) and good agreement (with all data points in the Bland-Altman plot falling within the limits of agreement) with those in portal vein blood flow measured by Doppler US.

Conclusion: ASL-MRI enables reliable quantification of liver perfusion in healthy individuals under both constant conditions and altered perfusion state induced by a meal. It holds great promise as a non-invasive tool for diagnosing liver disease.

Critical relevance statement: The short-term repeatability and postprandial effect of liver perfusion quantification using arterial spin labeling MRI in healthy subjects both exhibited excellent performance, indicating the potential of this technique as a non-invasive tool for diagnosing liver diseases.

Key points: Arterial spin labeling (ASL)-MRI enables reliable liver perfusion quantification in healthy individuals. ASL-MRI showed great short-term repeatability for liver perfusion measurement in the fasting state. ASL-MRI and US showed a moderate correlation in measuring postprandial portal venous hemodynamics change.

Keywords: Arterial spin labeling; Liver perfusion; Magnetic resonance imaging; Postprandial effect; Repeatability.

Fig. 1

Schematic of the complete experimental protocol (A), and typical images of arterial spin labeling MRI (B), and Ultrasonography (C)

Fig. 2

Field of view (FOV) and two labeling planes of ASL-MRI

Fig. 3

Liver segmentation and liver perfusion calculation process in ASL images

Fig. 4

Bland–Altman plots for analyzing the consistency of liver perfusion results between different measurements (N = 12). LP-A, liver perfusion from hepatic artery; LP-P, liver perfusion from portal vein; -i (i = 1, 2, 3) means results obtained from the i-th ASL measurement

Fig. 5

Pre- and postprandial liver blood flow parameters measured by ASL-MRI and Doppler ultrasonography (N = 11). LP-A, liver perfusion from hepatic artery; LP-P, liver perfusion from portal vein; PVF, blood flow volume in portal vein; -pre and -post, respectively, mean the pre-prandial and the postprandial state

Fig. 6

The linear regression (A) and Bland–Altman plot (B) between the relative postprandial change of LP-P measured by ASL and that of PVF measured by Doppler ultrasonography (N = 11). LP-P, liver perfusion from the portal vein; PVF, blood flow volume in the portal vein