Wen Qin, Presenter: Nothing to Disclose

Kun Cheng Li MD, Abstract Co-Author: Nothing to Disclose

Chun-shui Yu, Abstract Co-Author: Nothing to Disclose

Fan Zhang MD, Abstract Co-Author: Nothing to Disclose

Jianxin Cai, Abstract Co-Author: Nothing to Disclose

Analyzing the influential factors(TR,TE and field strength) of DTI and their relationships

Seven healthy mature Macaca rhesuses were performed MRI respectively on 3.0 tesla and 1.5 tesla Siemens MR scaners(trio Tim and Sonata).The imaging protocols include: single-shot EPI Diffusion tensor imaging sequence with (1) different TR ranging from 500 ms to 10000 ms(25 pionts), (2) different TE ranging from 70 ms to 160 ms（13 points).Imaging data was processed by matlab v6.5 and the FA and ADCmean were extracted for further comparision.

The average ADCmean value of putamen and internal capsule were 6.23x10-6mm²/s and 6.49x10-6mm²/s in 3.0T respectively and 6.99x10-6mm²/s and 7.10x10-6 mm²/s in 1.5T. There were no statistically significant differences between putamen and internal capsule(p=0.234 in 3.0T and 0.563 in 1.5T)but showed significant differences between different field strength(p=1500ms(p=0.289);and in 3.0T ,The FA of putamen are negative correlated with TR when TR=2500ms(p=0.276). The FA was significantly positive linear correlated with TE both in different field strengths and different tissues(P<0.001).

ADCmean and FA are field strength dependent.TE can significantly influence them.The effects of TR is more significant in low TR and low FA tissue.

TE,TR and field strength should be considered in clinical DTI applications.

Qin, W, Li, K, Yu, C, Zhang, F, Cai, J, The Effects of Field Strength, TR, and TE on Diffusion Tensor Imaging.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5014512.html