ELECTRONIC POSTER - ismrm

Tuesday 13:30-15:30 Computer 62
13:30 4092. Background Correction of Phase-Based Arterial Input Functions
Anders Garpebring 1 , Patrik Brynolfsson 1 , Ronnie Wirestam 2 , Nils Östlund 3 , Mikael
Karlsson 1
1 Radiation Sciences, Umeå University, Umeå, Sweden; 2 Medical Radiation Physics, Lund University, Lund,
Sweden; 3 Biomedical Engineering and Informatics, Umeå University Hospital, Umeå, Sweden
Phase sensitive MRI has shown great potential for quantification of the Arterial Input Function (AIF). However, motion induced phase
artefacts are problematic for in-vivo measurements and must be compensated for. The purpose of this study was to compare three
different background ROI selection procedures for compensation of phase errors. Results showed that efficient correction of motion
induced phase shifts requires a background ROI placed close to the vessel from which the AIF is sampled. Some further improvement
can also be achieved by tracking and compensating for any in-plane motion of the vessel.
14:00 4093. Preliminary Results with 3D DCE-MRI Curve Pattern Analysis of Treatment
Response in Osteosarcoma
Junyu Guo 1 , Qing Ji 1 , Mary E. McCarville 1 , Najat C. Daw 2 , Wilburn E. Reddick 1
1 Radiological Science, St Jude Children's Research Hospital, Memphis, TN, United States; 2 Department of
Oncology, St Jude Children's Research Hospital, Memphis, TN, United States
A new osteosarcoma treatment protocol in our Institute includes a multiagent chemotherapy with an anti-angiogenic agent
(bevacizumab). Serial DCE-MRI was performed at six different time points during neoadjuvant therapy, and a recently developed
DCE-MRI data analysis method, the CPA method, was used to process the data and assess treatment response in the first eight
patients. According to our preliminary results, it is feasible to assess the tumor treatment response to neoadjuvant therapy using the
CPA method in DCE-MRI. Further investigation of this CPA method on a larger cohort of patients will be performed.
14:30 4094. The Effect of Blood Inflow and B 1 -Field Inhomogeneity on Measurement of the AIF
in
Axial 3-D SPGR DCE-MRI
Caleb Roberts 1,2 , Ross A. Little 1,2 , Yvonne Watson 1,2 , Sha Zhao 1,2 , David L. Buckley 3 ,
Geoff J M Parker 1,2
1 Imaging Science and Biomedical Engineering, The University of Manchester, Manchester, United Kingdom,
United Kingdom; 2 The Biomedical Imaging Institute, The University of Manchester, Manchester, Greater
Manchester, United Kingdom; 3 Division of Medical Physics, University of Leeds, Leeds, United Kingdom
A major potential confound in axial 3-D dynamic contrast-enhanced MRI (DCE-MRI) studies is the blood inflow effect and therefore
the choice of slice location for arterial input function (AIF) measurement within the imaging volume must be considered carefully.
Using a combination of computer simulations, flow phantom and in vivo studies we describe and understand the effect of blood inflow
on the measurement of the AIF. We demonstrate that reliable AIFs are achievable in 3-D DCE-MRI but the use of inflow affected
AIFs in tracer kinetic modeling result in large errors in tissue microvascular parameters.
15:00 4095. Introducing New DCE Parametric Maps to Quantify Vascular Changes Induced by
the Anti-Angiogenic
Drug Sunitinib
Areen Al.Bashir 1,2 , Gilda Hillman 3 , Meng Li 2 , Yashwanth Katkur 2 , E. Mark Haacke 1,2
1 Department of Biomedical Engineeringt, Wayne State University, Detroit, MI, United States; 2 Department of
Radiology, Wayne State University, Detroit, MI, United States; 3 Department of Radiation Oncology, Wayne
State University
DCE-MRI has been routinely used to quantify the effectiveness of new anti-angiogenic drugs on the tumor vasculature using Gd-
DTPA as a contrast agent. However, this quantification is not easy. DCE has a lot of parameters that make it a very complex
technique, such as finding AIF and choosing the pharmacokinetic model. Hence, in this study, we introduced the new DCE parametric
maps which was calculated from Gd concentration, C(t), data. Regional analysis were preformed on 4 groups of mice treated with
different dose of the anti-angiogenic drug, sunitinib, and the results compared. Our results demonstrate that DCE parametric maps
have the potential to quantify the effect of new anti-angiogenic drugs on tumor and normal tissues. These findings were confirmed
with histological observations.