Utility of arterial spin labelling MRI for discriminating atypical high-grade glioma from primary central nervous system lymphoma. Issue 2 (February 2019) - Di, N.
Abstract : Aim: To evaluate the ability of arterial spin labelling (ASL) magnetic resonance imaging (MRI) in differentiating primary central nervous system lymphoma (PCNSL) from atypical high-grade glioma (HGG), as well as exploring the underlying pathological mechanisms. Methods and materials: Twenty-three patients with PCNSL and 17 patients with atypical HGG who underwent ASL-MRI were identified retrospectively. Absolute cerebral blood flow (aCBF) and normalised cerebral blood flow (nCBF) values were obtained, and were compared between PCNSL and atypical HGG using the Mann–Whitney U -test. The performance in discriminating between PCNSL and atypical HGG was evaluated using receiver-operating characteristics analysis and area-under-the-curve (AUC) values for aCBF and nCBF. The correlation between microvessel density (MVD) and aCBF was determined by Spearman's correlation analysis. Results: Atypical HGG demonstrated significantly higher aCBF, nCBF, and MVD values than PCNSL ( p <0.05). The diagnostic accuracy of discriminating PCNSL from atypical HGG showed AUC=0.877 (95% confidence interval [CI] 0.735–0.959) for aCBF, and AUC=0.836 (95% confidence interval [CI] 0.685–0.934) for nCBF. There was a moderate positive correlation between aCBF values of region of interest (ROI >30 mm 2 ) in the enhanced area and MVD values (rho=0.579, p =0.0001), and a strong positive correlation between aCBF values MVD based on "point-to-point biopsy" (rho=0.83, p =0.0029). Interobserver agreements for aCBF and nCBF were excellent (ICC >0.75). Conclusions: ASL perfusion MRI is a useful imaging technique for the discrimination between atypical HGG and PCNSL, which may be determined by the difference of MVD between them. Highlights: ALS derived aCBF and nCBF were a highly reproducible MR perfusion parameters clinically. aCBF and nCBF values were higher in atypical HGG than in PCNSL. ASL-MRI was an useful perfusion technique for differentiating atypical HGG from PCNSL. aCBF was positive correlated with MVD.