Abstract #0705

Amide Proton Transfer (APT) MR Signal As a Novel Imaging Biomarker for Charactering Radiation Necrosis in Rats

Silun Wang¹, Erik Tryggestad², Michael Armour², Eric Ford², Tingting Zhou¹, Kun Yan¹, Zhibo Wen¹, Peter C. M. van Zijl^1,3, Jinyuan Zhou^1,3

¹Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; ²Radiation Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; ³F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute

We evaluated radiation-induced necrosis in a rat model (40 Gy, 1010 mm2) using a multi-parametric MRI protocol, including diffusion, perfusion, and amide proton transfer (APT) imaging. Results showed that radiation necrosis consisted of a hypointense central zone and an iso-intense to slightly hyperintense peripheral zone on APT imaging, which reflected coagulative necrosis and reactive brain tissue, respectively. APT imaging can provide useful diagnostic information to assess radiation necrosis.