1. 1 Comparison of Different Diffusion Weighting Techniques Using Mutual Information Registration LAE 2/29/07

2. 2 Manuscript in Preparation See http://www.u.arizona.edu/~lewell/reg/http://www.u.arizona.edu/~lewell/reg/ Comparison of Different Diffusion Weighting Techniques Using Mutual Information Registration

3. 3 We have compared isotropic echo planar diffusion weighting to radial diffusion weighting utilizing mutual information registration with T2 FLAIR non-diffusion weighted images of the human brain. For slices near the middle of the brain, we see little difference. However, for inferior slices closer to the para-nasal cavities, we see an advantage with radial diffusion compared to echo planar. Abstract

4. 4 Comparison of Different Diffusion Weighting Techniques Using Mutual Information Registration Motivation Lesion contoured on non-diffusion weighted scan: e.g., T2 FLAIR. Contour must be transcribed to DWMRI in order to calculate Apparent Diffusion Coefficient (ADC) used to monitor therapy efficacy. Most common form of isotropic DW, Echo Planar, has limitations in inferior positions: geometric distortion, poor spatial resolution and intravoxel dephasing.  Need for more robust form of DWMRI.

5. 5 Comparison of Different Diffusion Weighting Techniques Using Mutual Information Registration Radial Diffusion(b=0) Echo Planar(b=0) T2 FLAIR

6. 6 Comparison of Different Diffusion Weighting Techniques Using Mutual Information Registration Analysis by N. Vijayakumar