TRADITIONAL POSTER - ismrm

Poster Sessions
2340. A Qualitative Comparison of Magnetic Resonance Images of Brain Acquired Using Phased-Array
Head Coils with 32 and 12 Array Elements at 1.5 Tesla
Pankit Parikh 1 , Gurpreet Singh Sandhu 1,2 , Kristine A. Blackham 1 , Michael D. Coffey 1 , Daniel P. Hsu 1 ,
John A. Jesberger 2 , Kecheng Liu 3 , Mark A. Griswold 1,4 , Jeffrey L. Sunshine 1,2
1 Radiology, University Hospitals of Cleveland, Case Western Reserve University, Cleveland, OH, United States; 2 Case Center for
Imaging Research, Case Western Reserve University, Cleveland, OH, United States; 3 Siemens Healthcare, Malvern, PA, United
States; 4 Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
Phased-array coils with increasing number of array elements have been developed and employed for clinical MR imaging. A phased-array head coil with 32
array elements provides quantitatively better brain images as compared to commercially available head coil with lower number of array elements. In this
study, we investigate if application of this coil would improve the anatomic and pathologic analysis from the resultant brain images by qualitatively
comparing MR images obtained using this coil with those obtained using a commercially available phased-array head coil with 12 array elements.
2341. Looking at Magnetization Exchange in Human White Matter Structures in Vivo
Saeed Kalantari 1 , Cornelia Laule 2 , Thorarin Bjarnason 3 , Alex MacKay 1,2
1 Department of Physics and Astronomy, University of British Columbia Hospital, Vancouver, BC, Canada; 2 Department of
Radiology, University of British Columbia Hospital, Vancouver, BC, Canada; 3 Department of Electrical and Computer Engineering,
University of Calgary
The objective of this study was to measure the cross relaxation exchange time between the myelin water and intra/extracellular water pools in healthy human
white matter in vivo. Five different white matter structures were investigated. Bloch equations were solved analytically and cross relaxation exchange times
were extracted. Due to the ambiguity in the literature on spin-lattice relaxation times in white matter, three T1 scenarios were developed. The extracted cross
relaxation times were then used to estimate the exchange corrections for myelin water fraction (MWF) measurements. The choice of T1 scenario had a
significant effect on cross relaxation times and consequently on MWF corrections.
2342. A Head Mimicking Phantom for 7T, Matched for Tissue Parameters, B1+ Behavior, and Coil Loading
Effects
Andrew T. Curtis 1,2 , Lauren E. Villemaire 2 , Kyle M. Gilbert 1 , Ravi S. Menon 1,2
1 Centre for Functional and Metabolic Mapping, Robarts Research Institute, London, Ontario, Canada; 2 Medical Biophysics, The
University of Western Ontario, London, Ontario, Canada
An agarose gel and saline solution phantom was developed to mimic properties of the human brain at 7T. This design provides many parameters matched to
the behaviour seen in vivo including: grey matter/white matter contrast for sequence development, matched B1+ interference (RF wavelength) behaviour,
and coil loading effects.
2343. Simple and Efficient Image Processing Techniques to Improve the Registration Between the MR and
Light Microscopy Images
Xia Li 1,2 , Ann Choe, 2,3 , Yurui Gao 3,4 , Iwona Stepniewska 3 , Adam Anderson 3,4
1 Radiology, Vanderbilt University, Nashville, TN, United States; 2 Institute of Imaging Science, Vanderbilt University, Nashville, TN,
United States; 3 Biomedical Engineering, Vanderbilt University; 4 Institute of Imaging Science,, Vanderbilt University, Nashville, TN,
United States
The light microscopy images have a high spatial resolution and are usually co-registered to the corresponding MR images in order to make the comparison.
However, there are artifacts, such as tearing, deformation, or disappearance of tissue fragments, in the stained slices. Those artifacts make the registration
among MR, blockface, and light images more difficult. In this study, two image post-processing techniques are introduced, which can provide a better
initialization to the nonrigid registration algorithm.
General Neuroimaging
Hall B Thursday 13:30-15:30
2344. Inter-Reader Reproducibility for Carotid Territory Cerebral Vascular Infarcts: A 3.0T Magnetic
Resonance Imaging Study
Wei Yu 1 , Li Dong, 12 , Lu Zhou 1 , Dan Hipper 2 , Marina Fergurson 2 , Guangrui Liu 1 , Dean Shibata 2 , Chun
Yuan 2 , Zhaoqi Zhang 1
1 Beijing Anzhen Hospital, Capital Medical University, Beijing, China; 2 University of Washington, Seattle, WA, United States
We determined the inter-reader reproducibility in the assessment of carotid territory brain lesions. In a carotid study, two reviewers reviewed brain images of
134 hemispheres from 67 subjects independently. The inter-reader agreement was substantial for the lesion presence (κ = 0.67; 0.54-0.80) and the lesion
size (κ = 0.75; 0.60-0.92), and there was complete agreement (κ = 1.0) for age. Some disagreements on the presence or absence of lesions may be due to
their location near the boundary of the carotid territory. It is important to point out small old lesions were the primary factor that reduced reproducibility.