Kyu-Ho Song1, Sang-Young Kim1, Do-Wan Lee1, Jin-Young Jung1, Jung-Hoon Lee1, Hyeon-Man Baek2, Bo-Young Choe3. 1. Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea. 2. 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. 3. 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.
Abstract
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. NEW METHOD: 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). COMPARISON WITH EXISTING 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.
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. NEW METHOD: 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). COMPARISON WITH EXISTING 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.