Jeremy David Hoisak1,2, Eng-Siew Koh1,3,
1Radiation Medicine Program, Princess
Margaret Hospital, Toronto, Ontario, Canada; 2Medical Biophysics,
University of Toronto, Toronto, Ontario, Canada; 3Radiation
Oncology, University of Toronto, Toronto, Ontario, Canada; 4Medical
Imaging, University of Toronto, Toronto, Ontario, Canada
Response
assessment with a voxel-wise analysis of serial image change has advantages
over conventional tumor measurements, but is susceptible to uncertainties
from inconsistent voxel correspondences between scans arising from a dynamic
tumor morphology. A correspondence correction method based on a metric of
voxel similarity was applied to a functional diffusion map (fDM) analysis of
co-registered T1-weighted and diffusion-weighted images of glioblastoma
multiforme acquired pre- and post-chemoradiotherapy. The correction resulted
in a statistically significant alteration in the quantification of apparent
diffusion coefficient (ADC) change pre- and post-therapy, and has the
potential to improve the accuracy of subsequent determinations of therapy
outcome.