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OBJECTIVES To explore the feasibility of evaluating the aortopulmonary collateral flow (APCF) and pulmonary vascular growth of patients who underwent bidirectional Glenn shunting (BGS) using phase-contrast magnetic resonance imaging (PC-MRI) and contrast-enhanced magnetic resonance imaging (CE-MRI). METHODS Blood flow measurements of the great vessels of the body were recorded in 22 post-BGS patients using 3.0 T PC-MRI. Right and left pulmonary blood flow (QP), stroke volume (SV) of the ascending aorta (QS), blood flow of descending aorta (Qd) and venous return of the superior and inferior venae cavae (QV) per minute were calculated using the Report Card software. APCF was equal to the difference between QS and QV. The parameters for pulmonary vascular growth were assessed using CE-MRI. The relationship between pulmonary vascular growth and APCF was evaluated using correlation analysis. A comparative analysis was conducted between the MRI results and the results of five cases who underwent cardiac catheterization and 10 cases who underwent angiography. RESULTS Estimated APCF ranged from 0.23 to 1.63 l/(min/m2), accounting for 5–44% of QS. Morphologic abnormalities such as pulmonary stenosis, dilatation and thrombosis were clearly visualized through CE-MRI. Significant differences in individual pulmonary artery growth were observed. A significant negative correlation was found between APCF and the pulmonary artery index (PAI; r = −0.461, P = 0.031) when the McGoon rate was 2.04 ± 0.59 and the PAI was 253.27 ± 85.86 mm2/m2. Good consistency or relativity was found between cardiac catheterization, angiography and MRI. CONCLUSIONS Assessing the APCF and parameters for pulmonary vascular growth in patients who underwent BGS is feasible using 3.0 T PC-MRI integrated with CE-MRI, which may play an important role in clinical and therapeutic decision-making and prognostic evaluation. [ABSTRACT FROM AUTHOR]

Objectives: To present a multi-delay pseudo-continuous ASL (pCASL) protocol that offers simultaneous measurements of cerebral blood flow (CBF) and arterial transit time (ATT), and to study correlations between multi-delay pCASL and CT perfusion in moyamoya disease. Methods: A 4 post-labeling delay (PLD) pCASL protocol was applied on 17 patients with moyamoya disease who also underwent CT perfusion imaging. ATT was estimated using the multi-delay protocol and included in the calculation of CBF. ASL and CT perfusion images were rated for lesion severity/conspicuity. Pearson correlation coefficients were calculated across voxels between the two modalities in grey and white matter of each subject respectively and between normalized mean values of ASL and CT perfusion measures in major vascular territories. Results: Significant associations between ASL and CT perfusion were detected using subjective ratings, voxel-wise analysis in grey and white matter and region of interest (ROI)-based analysis of normalized mean perfusion. The correlation between ASL CBF and CT perfusion was improved using the multi-delay pCASL protocol compared to CBF acquired at a single PLD of 2 s ( P < 0.05). Conclusions: There is a correlation between perfusion data from ASL and CT perfusion imaging in patients with moyamoya disease. Multi-delay ASL can improve CBF quantification, which could be a prognostic imaging biomarker in patients with moyamoya disease. Key Points: • Simultaneous measurements of CBF and ATT can be achieved using multi-delay pCASL. • Multi-delay ASL was compared with CT perfusion in patients with moyamoya disease. • Statistical analyses showed significant associations between multi-delay ASL and CT perfusion. • Multi-delay ASL can improve CBF quantification in moyamoya disease. [ABSTRACT FROM AUTHOR]