Abstract #2544

Diffusion MRI and Contrast-Enhanced Monitoring of Prostate Microwave Focal Thermal Therapy: An In-Vivo Canine Study

Hai-Ling Margaret Cheng^1,2, Masoom A. Haider³, Marcus J. Dill-Macky⁴, Joan M. Sweet⁵, John Trachtenberg⁶, Mark R. Gertner^7,8

¹Research Institute & Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada; ²Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; ³Medical Imaging, University Health Network and Mount Sinai Hospital; ⁴Pathology & Laboratory Medicine, University Health Network; ⁵Pathology & Laboratory Medicine, University Health Network, University of Toronto; ⁶Surgery, University Health Network; ⁷Biophysics & Bioimaging, University Health Network; ⁸Physics, Ryerson University

Diffusion MRI for monitoring thermal therapy has received much less attention than contrast-enhanced (CE) methods but is potentially more useful because of its repeatability. In this study, microwave heating of normal canine prostates was monitored with diffusion MRI, CE MRI, and CE ultrasound. CE images revealed an area of low uptake that was smaller than the red ring of thermal damage on histology. However, a well defined ring of reduced diffusion was consistently seen and was shown to correspond to the red ring. Diffusion MRI may be more accurate than CE methods in predicting the eventual extent of thermal damage.