RT Journal Article SR Electronic T1 Improved Conspicuity and Delineation of High-Grade Primary and Metastatic Brain Tumors Using “Restriction Spectrum Imaging”: Quantitative Comparison with High B-Value DWI and ADC JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology DO 10.3174/ajnr.A3327 A1 N.S. White A1 C.R. McDonald A1 N. Farid A1 J.M. Kuperman A1 S. Kesari A1 A.M. Dale YR 2012 UL http://www.ajnr.org/content/early/2012/11/08/ajnr.A3327.abstract AB BACKGROUND AND PURPOSE: Restriction spectrum imaging is a sensitive DWI technique for probing separable water diffusion compartments in tissues. Here, we evaluate RSI-CMs derived from the spherically-restricted water compartment for improved tumor conspicuity and delineation from nontumor tissue and reduced sensitivity to edema compared with high-b-value DWI and ADC. MATERIALS AND METHODS: RSI was performed in 10 presurgical patients: 4 with glioblastoma, 3 with primary CNS lymphoma, and 3 with metastatic brain tumors. Multidirectional DWI data were collected at b = 500, 1500, and 4000 s/mm2. Quantification of tumor conspicuity, edema conspicuity, and relative sensitivity to edema for RSI-CMs; DWI at b = 4000 (DWI-4000); and ADC were compared in manually drawn VOIs. Receiver operating characteristic curves were used to evaluate the sensitivity and specificity of each method for delineating tumor from normal-appearing WM. RESULTS: Significant TC was seen with both RSI-CMs and DWI-4000, but not ADC. Significant EC was seen with ADC, but not RSI-CMs or DWI-4000. Significantly greater TC was seen with RSI-CMs compared with DWI-4000. Significantly reduced RSE was seen with RSI-CMs compared with both DWI-4000 and ADC. Greater sensitivity and specificity for delineating tumor from normal-appearing WM were seen with RSI-CMs (AUC = 0.91) compared with both DWI-4000 (AUC = 0.77) and ADC (AUC = 0.66). CONCLUSIONS: RSI-CMs offer improved conspicuity and delineation of high-grade primary and metastatic brain tumors and reduced sensitivity to edema compared with high-b-value DWI and ADC. Abbreviations AUCarea under the receiver operating characteristic curveECedema conspicuityRSErelative sensitivity to edemaRSIrestriction spectrum imagingRSI-CMRSI cellularity mapTCtumor conspicuity