Shengyong Wu MD, Presenter: Employee, VirtualScopics, Inc

Fei Yuan MD, Abstract Co-Author: Nothing to Disclose

Jianhui Zhong PhD, Abstract Co-Author: Nothing to Disclose

Zhuoli Zhang MD, PhD, Abstract Co-Author: Nothing to Disclose

Yinshe Liu, Abstract Co-Author: Nothing to Disclose

Ji Qi MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the corpus callosum (CC) involvement and its characteristic in subcortical ischemic vascular dementia (SIVD) patients and to demonstrate the relationship between the DTI parameters and cognitive status.

Thirty-four patients (mean age 70.3±9.7 years) with SIVD diagnosed by the criteria of NINDS/AIREN, and 26 age-matched cognitively normal (CN) older adults (mean age 64.8±10.4 years) participated in the study. MMSE score was obtained for all subjects. Conventional MR images and DTI were obtained on a Philips Intera 3T scanner. DTI images were performed (b=800 s/mm2, TR/TE 10514/71 ms, SENSE factor 2) and the data were post-processed using Fiber Tracking 4.1V3 Beta3 software. Fractional anisotropy (FA), PA (principal anisotropy, FApri) and ADC vaules were measured for the splenium, body and genu part of CC. Student's t-tests were used for comparisons of FA, PA and ADC values between two groups, and Pearson's Correlation assessment between DTI values and clinical materials was analysed.

MMSE scores were 28.96±1.14 in the CN and 20.15±1.56 in the SIVD groups, and HIS was 10.35±2.46 for the latter. FA maps and DTI tractography of CN group showed high integrity and uniformity of fiber structures in the genu, body, and splenium of CC, in frontal forceps, occipital forceps, and the white matter radiation interconnecting the cerebral hemispheres. FA maps in SIVD patients showed irregularity of the border of CC, which cannot be reconstructed entirely in DTI tractography, and the reduced number of fibres and structural disintegration were seen in SIVD patients. FA, PA values for the splenium (0.451±0.042, 0.629±0.135) and genu (0.731±0.090, 0.723±0.085) of CC in SIVD group with higher ADC were significantly lower than those of the CN group (FA, 0.545±0.050, 0.797±0.051; PA, 0.712±0.190, 0.792±0.060) (p<0.05, respectively). FA and PA values in left posterior periventricular WM were significantly lesser than those in right side. A negative correlation was found between SIVD MMSE and mean ADC values for the genu of CC (r=-0.361, p=0.036) .

DTI can illustrate deterioration of white matter integrity of CC, which may be a potential indicator of morphological substrates of cognitive dysfunction by quantitative assessment in SIVD patients.

Further investigation into using DTI parameters in CC as a possible diagnostic biomarker of SIVD is warranted.

Wu, S, Yuan, F, Zhong, J, Zhang, Z, Liu, Y, Qi, J, Assessment of the Corpus Callosum with MR Diffusion Tensor Imaging (DTI) in Subcortical Ischemic Vascular Dementia Patients.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8000422.html