E.436 - Arterial spin labeling (ASL) technique could be used as standard clinical tool?

Abstract

Introduction: The twomost commonmethods formeasuring perfusion using MRI are the Dynamic Susceptibility Contrast (DSC) approach, which identifies the passage of an intravascular contrast agent, and the Arterial Spin Labeling (ASL), which uses magnetically labeled arterial bloodwater as a diffusible flow tracer. DSC perfusion is still the more widely applied clinical technique but recent technical advances have improved the sensitivity of ASL perfusion. It has been argued that ASL perfusion images are not clinically reliable due to the low SNR. The objective of the current study was to evaluate the regional correlation between ASL perfusion measurement of CBF in healthy subjects and patients with brain tumors in different brain areas. Materials and Methods: 35 subjects were enrolled: 27 healthy subjects (19 m/17 f, 44.6 y) and 8 patients (4 m/3 f, 57 y) with different brain lesions. The study was performed using a 1.5 T MR scanner. Each subject received an ASL scan and all the routine clinical MRI scans; a DSC scan was also acquired only for patients. For all subjects, a series of ROIs in correspondence to the white matter (WM) and gray matter (GM) have been drawn on the ASL-CBF map; the same ROIs were also positioned on DSC-CBF map for all patients. The perfusion ASL values from different regions were analyzed using non parametric t-test. For patients, the ASL and DSC data have also been compared. Results and Conclusions: From the comparison between the ASL values it was found that the values of the CBF were statistically higher in the GM (33.5 ± 5.8 ml/100g/min) with respect to the WM (17.1 ± 5.7 mL/100g/min) as expected. Frompatient data analysis, it was evident that ASL andDSC values are in agreement with the type of lesions, WM, GM. Our study confirmed that the ASL technique represents a valid alternative to conventional DSC. In our experience the ASL was able to highlight the topographical distribution of CBF and to locate in patients ischemic and glial lesions.