Design of a fused phantom for quantitative evaluation of brain metabolites and enhanced quality assurance testing for magnetic resonance imaging and spectroscopy.
BACKGROUND
Magnetic resonance imaging and spectroscopy (MRI-MRS) is a useful tool for the identification and evaluation of chemical changes in anatomical regions. Quality assurance (QA) is performed in either images or spectra using QA phantom. Therefore, consistent and uniform technical MRI-MRS QA is crucial.


METHODS
Here we developed an MRI-MRS fused phantom along with the inserts for metabolite quantification to simultaneously optimize QA parameters for both MRI and MRS. T1- and T2-weighted images were obtained and MRS was performed with point-resolved spectroscopy.


RESULTS
Using the fused phantom, the results of measuring MRI factors were: geometric distortion, <2% and ± 2 mm; image intensity uniformity, 83.09 ± 1.33%; percent-signal ghosting, 0.025 ± 0.004; low-contrast object detectability, 27.85 ± 0.80. In addition, the signal-to-noise ratio of N-acetyl-aspartate was consistently high (42.00 ± 5.66).


METHODS
In previous studies, MR phantoms could not obtain information from both images and spectra in the MR scanner simultaneously. Here we designed and developed a phantom for accurate and consistent QA within the acceptance range. It is important to take into account variations in the QA value using the MRI-MRS phantom, when comparing to other clinical or research MR scanners.


CONCLUSIONS
The MRI-MRS QA factors obtained simultaneously using the phantom can facilitate evaluation of both images and spectra, and provide guidelines for obtaining MRI and MRS QA factors simultaneously.
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Kyu-Ho
KH
Song
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Sang-Young
SY
Kim
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Do-Wan
DW
Lee
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Jin-Young
JY
Jung
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea.
Jung-Hoon
JH
Lee
Center for Magnetic Resonance Research, Korea Basic Science Institute, Chungbuk 363-883, Republic of Korea; Department of Bio-Analytical Science, Korea University of Science and Technology, Daejeon 305-333, Republic of Korea.
Hyeon-Man
HM
Baek
Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea. Electronic address: bychoe@catholic.ac.kr.
Bo-Young
BY
Choe
D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D001931:Brain Mapping / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation* / Q000379:methods; D019047:Phantoms, Imaging; D011785:Quality Assurance, Health Care / Q000379:methods; D059629:Signal-To-Noise Ratio; D014867:Water
D014867:Water; D001224:Aspartic Acid; C000179:N-acetylaspartate
MRI–MRS phantom; Metabolite quantification; Single voxel spectroscopy; T1-weighted image; T2-weighted image