TY - JOUR T1 - A Novel Methodology for Applying Multivoxel MR Spectroscopy to Evaluate Convection-Enhanced Drug Delivery in Diffuse Intrinsic Pontine Gliomas JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. DO - 10.3174/ajnr.A4713 AU - D.I. Guisado AU - R. Singh AU - S. Minkowitz AU - Z. Zhou AU - S. Haque AU - K.K. Peck AU - R.J. Young AU - A.J. Tsiouris AU - M.M. Souweidane AU - S.B. Thakur Y1 - 2016/03/03 UR - http://www.ajnr.org/content/early/2016/03/03/ajnr.A4713.abstract N2 - BACKGROUND AND PURPOSE: Diffuse intrinsic pontine gliomas are inoperable high-grade gliomas with a median survival of less than 1 year. Convection-enhanced delivery is a promising local drug-delivery technique that can bypass the BBB in diffuse intrinsic pontine glioma treatment. Evaluating tumor response is critical in the assessment of convection-enhanced delivery of treatment. We proposed to determine the potential of 3D multivoxel 1H-MR spectroscopy to evaluate convection-enhanced delivery treatment effect in these tumors.MATERIALS AND METHODS: We prospectively analyzed 3D multivoxel 1H-MR spectroscopy data for 6 patients with nonprogressive diffuse intrinsic pontine gliomas who received convection-enhanced delivery treatment of a therapeutic antibody (Phase I clinical trial NCT01502917). To compare changes in the metabolite ratios with time, we tracked the metabolite ratios Cho/Cr and Cho/NAA at several ROIs: normal white matter, tumor within the convection-enhanced delivery infusion site, tumor outside of the infused area, and the tumor average.RESULTS: There was a comparative decrease in both Cho/Cr and Cho/NAA metabolite ratios at the tumor convection-enhanced delivery site versus tumor outside the infused area. We used MR spectroscopy voxels with dominant white matter as a reference. The difference between changes in metabolite ratios became more prominent with increasing time after convection-enhanced delivery treatment.CONCLUSIONS: The comparative change in metabolite ratios between the convection-enhanced delivery site and the tumor site outside the infused area suggests that multivoxel 1H-MR spectroscopy, in combination with other imaging modalities, may provide a clinical tool to accurately evaluate local tumor response after convection-enhanced delivery treatment.AbbreviationsCEDconvection-enhanced deliveryDIPGdiffuse intrinsic pontine gliomaMRSIMR spectroscopic imagingpreCED1 week prior to CED treatmentpostCED11 day after CED treatmentpostCED21 month after CED treatmentpostCED32 months after CED treatment ER -