RT Journal Article SR Electronic T1 T1-Weighted, Dynamic Contrast-Enhanced MR Perfusion Imaging Can Differentiate between Treatment Success and Failure in Spine Metastases Undergoing Radiation Therapy JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1451 OP 1457 DO 10.3174/ajnr.A8057 VO 44 IS 12 A1 Behar, Mark A1 Peck, Kyung K. A1 Yildirim, Onur A1 Tisnado, Jamie A1 Saha, Atin A1 Arevalo-Perez, Julio A1 Lis, Eric A1 Yamada, Yoshiya A1 Holodny, Andrei I. A1 Karimi, Sasan YR 2023 UL http://www.ajnr.org/content/44/12/1451.abstract AB BACKGROUND AND PURPOSE: Current imaging techniques have difficulty differentiating treatment success and failure in spinal metastases undergoing radiation therapy. This study investigated the correlation between changes in dynamic contrast-enhanced MR imaging perfusion parameters and clinical outcomes following radiation therapy for spinal metastases. We hypothesized that perfusion parameters will outperform traditional size measurements in discriminating treatment success and failure.MATERIALS AND METHODS: This retrospective study included 49 patients (mean age, 63 [SD, 13] years; 29 men) with metastatic lesions treated with radiation therapy who underwent dynamic contrast-enhanced MR imaging. The median time between radiation therapy and follow-up dynamic contrast-enhanced MR imaging was 62 days. We divided patients into 2 groups: clinical success (n = 38) and failure (n = 11). Failure was defined as PET recurrence (n = 5), biopsy-proved (n = 1) recurrence, or an increase in tumor size (n = 7), while their absence defined clinical success. A Mann-Whitney U test was performed to assess differences between groups.RESULTS: The reduction in plasma volume was greater in the success group than in the failure group (−57.3% versus +88.2%, respectively; P < .001). When we assessed the success of treatment, the sensitivity of plasma volume was 91% (10 of 11; 95% CI, 82%–97%) and the specificity was 87% (33 of 38; 95% CI, 73%–94%). The sensitivity of size measurements was 82% (9 of 11; 95% CI, 67%–90%) and the specificity was 47% (18 of 38; 95% CI, 37%–67%).CONCLUSIONS: The specificity of plasma volume was higher than that of conventional size measurements, suggesting that dynamic contrast-enhanced MR imaging is a powerful tool to discriminate between treatment success and failure.DCEdynamic contrast-enhancedΔVpchange in plasma volumeKtransvessel permeabilityROCreceiver operating characteristicRTradiation therapyVpplasma volume