accurate quantification of choline-to-creatine ratio as a biomarker to distinguish osteosarcoma patients from normal subjects employing proton magnetic resonance spectroscopy imaging at 3 tesla

Purpose: this study focused on accurate quantification of a maximum of choline-to-creatine ratio (max (cho/cr)) in 10 osteosarcoma patients, in comparison with 5 healthy volunteers as our control group using proton magnetic resonance spectroscopy imaging (1h-mrsi). materials and methods: max (cho/cr) were obtained in 10 patients with osteosarcoma over their corresponding ratio maps containing diseased tissue, to be compared with cho/cr in 5 healthy volunteers at 3t, employing mrsi (performed employing pointed-resolved spectroscopy (press), tr/te: 2500s /135 ms) with water-suppression. an extra unsuppressed water single-voxel spectroscopy (svs) was acquired to provide phase information for further eddy current correction (ecc). multi-stage preprocessing was applied. subtract quest mrsi as a time-domain technique was employed to accurately quantify the metabolites’ ratios and to estimate the baseline. results: an optimal database for subtract quest was achieved based on multiple trials evaluated by acceptable peak-fitting and cramer-rao-bound (crb). lipids at frequencies of 0.94 and 1.33ppm were combined to increase the accuracy of the lipid estimation. conclusion: estimation of max (cho/cr) evaluated over cho/cr spatial maps to distinguish osteosarcoma patients from normal subjects suggested that the proposed quantification method leads to high power and linear classifier with a high degree of reproducibility, considering 1h-mrsi at 3t machine as a high efficacy diagnostic tool for musculoskeletal radiology.