Arterial spin-labeled magnetic resonance perfusion imaging in prediction of pediatric brain tumors grading: inter-observer agreement

Abstract

Abstract Background Pediatric brain tumors are a major concern with many variable management options. Arterial spin-labeled magnetic resonance perfusion imaging is a relatively new and noninvasive technique that can help in predicting tumor grades and provide us with physiological data about the tumors which significantly aids in all stages of tumor care, including diagnosis, therapy, and follow-up. Aim of the study To determine agreement between independent observers in the assessment and prediction of brain tumor grading in pediatrics by arterial spin-labeled (ASL) magnetic resonance perfusion imaging. Methods Thirty-two patients (21 boys and 11 girls; mean age of (10.28 ± 4.31) years) with brain tumors were evaluated by ASL MRI perfusion. Image analysis was performed by two reviewers for quantifying absolute and relative tumoral blood flow (aTBF and rTBF) as well as qualitative assessment of the tumors in ASL color map images. Results The inter-observer agreement for the mean aTBF and the mean rTBF values of the studied lesions was almost perfect (inter-class correlation coefficient (ICC) = 0.978, 0.997). There was substantial agreement between both observers for the qualitative assessment of the studied lesions in color ASL images (Kappa = 0.779, with % of agreement = 87.0%). The mean aTBF for grade I tumors was (24.64 ± 3.45 ml/100 g/min), for grade II tumors it was (33.81 ± 3.59 ml/100 g/min), while for high-grade tumors (grade III and IV tumors) it was (75.60 ± 20.0 ml/100 g/min) with (p < 0.001). The mean rTBF of grade I, II, and III/IV tumors was (1.01 ± 0.17); (1.07 ± 0.31); and (3.12 ± 0.24) with (p < 0.001). Conclusions Arterial spin-labeled perfusion MRI can help in the challenge of prediction of brain tumor grading in pediatrics with accurate quantitative and semi-quantitative measurements of perfusion parameters of the tumors as well as qualitative and visual assessment of the tumors.