Purpose: The purpose of this study was to assess tumor vascularity of the brain by dynamic susceptibility contrast (DSC) MR imaging and to determine whether this method is clinically useful for monitoring radiation effects on brain tumors. We, furthermore, compared DSC MR imaging with single-photon emission computed tomography (SPECT) using technetium-99m diethylene-triamine-pentaacetic acid human serum albumin (99mTc-HSA-D) in the assessment of tumor vascularity in a limited numbers of cases.
Methods: Twelve patients with various kinds of brain tumors were studied. DSC MRI was performed on all patients before and after radiation therapy. SPECT using 99mTc-HSA-D was also performed in five patients. The rate of change in tumor blood volume in response to radiation therapy was evaluated with DSC MRI and SPECT. The rate of change in tumor volume in response to radiation was also measured.
Results: Ten patients were successfully studied. The rate of change in tumor blood volume correlated well between DSC MRI and SPECT. There was no significant correlation between the rates of change for tumor blood volume and tumor volume. Changes in tumor vascularity preceded the reduction in tumor volume seen following radiotherapy.
Conclusion: DSC MRI provides information regarding radiation effects on tumor vessels that is not available with conventional MRI.