Dynamic contrast T1 perfusion MRI findings for evaluating early treatment response to radiosurgery in intracranial meningiomas

Early predilection of treatment response after radiosurgery in intracranial meningioma is critical for determining patient management. Early imaging evaluation of tumor volumes may not accurately predict the treatment response. The aim of this study was to evaluate the DCE-MRI findings to predict tumor response to radiosurgery in the early post-treatment period. Seventeen meningiomas of 15 patients who underwent gamma knife were included. DCE-MRI was obtained prior to radiosurgery and at 1 and 6 months after radiosurgery. Perfusion parameters were analyzed using software programs on the workstation. Tumor volume was calculated from morphological sequences. DCE-MRI parameters obtained in the early post-treatment periods were analyzed and compared with volumetric data. There was no difference in average tumor volume at 1 month after treatment. Although there was a decrease in the average tumor volume at 6 months, all cases were found to be in the stable disease category according to the RANO criteria. Ktrans significantly decreased both at 1 month and 6 months. There was a significant difference in the Kep value at 6 months compared to pre-treatment imaging. The proportional decrease in Ktrans was found to be more significant at 1 month and 6 months compared to the tumor volume. In patients with meningioma who underwent radiosurgery, evaluation of treatment response based on morphological findings can be insufficient in the early period. DCE-MRI has the potential to predict the treatment response in the early post-treatment period with the functional information it provides.