Hong Zhang MD, Presenter: Nothing to Disclose

Jinyuan Zhou PhD, Abstract Co-Author: Nothing to Disclose

Na Xu Zhao PhD, Abstract Co-Author: Nothing to Disclose

Yun Peng MD, Abstract Co-Author: Nothing to Disclose

APT imaging is able to extend the achievable magnetic resonance imaging (MRI) contrast to the protein level. The aim of this study was to investigate APT effect in healthy children.

Nineteen healthy children were investigated. All subjects were scanned on a Philips 3T MRI scanner (Achieva 3.0T TX). Single-slice APT imaging was acquired. All data processing procedures were performed using the interactive data language (IDL). The MTRasym(3.5 ppm) image was calculated. Regions of interest were carefully chosen by experienced radiologists. The regions of interest were drawn on relatively homogeneous white and gray matters of bilateral cerebral hemispheres. SPSS11.5 for Windows was used for data analysis. The distribution of the data was tested for using the Shapiro-Wilk normality test. All values are expressed as mean±standard deviation. Then, paired t-test was done to show if there was significant difference in MTRasym(3.5 ppm) values between white and gray matters. Statistical significance was accepted at p < 0.05.

Fig.1 shows an example of APT images for a volunteer. As shown in Fig.1, the APT signal intensities was greater in gray matter compared to white matter in volunteers. There was no statistically significant difference between the left and the right side of the brain in volunteers. So, the values from both sides were combined. The units of APT are percentage points in the water signal intensity, the values are -0.62±0.20 (white matter) and 0.25±0.34 (gray matter).There was statistically significant difference of APT signal intensities between white and gray matters. (t=-12.24,p=0.000). 

We have demonstrated the feasibility of APT imaging of normal brain in healthy children on a clinical 3T scanner. APT imaging at 3T revealed significant contrast between white and gray matters, with a higher APT signal apparent within the gray matter. These preliminary data from healthy children show that the APT is a unique contrast that can provide complementary information to standard clinical MRI measures.

APT imaging is able to extend the achievable MRI contrast to the protein level. We believe that APT imaging at 3T has the potential to become a noninvasive biomarker for some pediatric diseases. 

Zhang, H, Zhou, J, Zhao, N, Peng, Y, Amide Proton Transfer MR Imaging of the Brain in Children at 3T: A Preliminary Study.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13024831.html