Abstract #4051

A Comparative Study of MRI Diffusion-Related Parameters for the Early Detection of Radiation-Induced Tissue Changes in a Rodent Tumour Model

Frank Peeters¹, Dennis Rommel¹, Jorge Abarca-Quinones¹, Vincent Gregoire², Thierry Duprez¹

¹Medical Imaging, Universit Catholique de Louvain, Brussels, Belgium; ²Center for Molecular Imaging and Experimental Radiotherapy, Universit Catholique de Louvain, Brussels, Belgium

The diagnostic accuracy of diffusion MRI related parameters derived from different techniques should be empirically assessed. We have performed a comparative study for the assessment of early effects of radiation therapy in a rodent tumour model (rhabdomyosarcoma in rats). Parameters obtained from DTI (2-points ADC, mono- and bi-exponential fits) and q-space imaging (tensor analysis) were compared. Our study shows that diffusion coefficients were very sensitive to radiation-induced tissue changes. Q-space analysis yielded at least the most sensitive parameter: the excess kurtosis of the distribution. The mean value and anisotropy of the tensors detected different sub-areas within irradiated tissue.