Abstract #3919

Effect of Cerebral Hemodynamic Changes on DTI Quantitation: A Hypercapnia Study

Abby Ying Ding^1,2, Ed X. Wu^1,3

¹Laboratory of Biomedical Imaging & Signal Processing, the University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of; ²Department of Electrical & Electronic Engineering, the University of Hong Kong , Hong Kong, Hong Kong SAR, China, People's Republic of; ³Department of Electrical & Electronic Engineering, the University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of

The accuracy of DTI quantitation can directly affect the interpretation of underlying biological microstructures. DTI measurements can be confounded by the presence of vasculature and blood perfusion. So far, little is known about the extent of such effects in quantitative DTI. In this study, we quantitatively examined the effect of hypercapnia on quantitative DTI indices in vivo in rodent brains. DTI indices were found to alter during hypercapnia, including various diffusivities and FA. These findings indicated that alterations in physiologic condition, vascular characteristics and hemodynamic regulations can affect the in vivo quantitation of various DTI indices. Therefore, caution must be taken in designing experiments and interpreting DTI indices.