OBJECTIVE: Magnetic resonance imaging (MRI) at 3 T is significantly different than 1.5 T and needs to be optimized due to increased signal-to-noise ratio (SNR) and specific absorption ratio (SAR). This study tests the hypothesis that first-pass myocardial perfusion MRI using saturation recovery (SR)-TrueFISP with parallel imaging is superior to SR-TurboFLASH and a more achievable technique for clinical application at 3 T. MATERIALS AND METHODS: Myocardial perfusion imaging was performed on 12 subjects using SR-TurboFLASH and SR-TrueFISP sequences combined with parallel imaging. Four myocardial slices were acquired and evaluated by image segmentation. Quality of the measurements was determined from SNR, contrast-to-noise ratio (CNR), enhancement-to-noise ratio (ENR), and myocardial perfusion upslope. Data were analyzed using a 2-way ANOVA with imaging method and segment number as the independent variables. RESULTS: SNR, CNR, ENR, and upslope were significantly higher for SR-TrueFISP versus SR-TurboFLASH (P < 0.001). Significant differences in SNR, CNR, ENR, and upslope were found among the myocardial segments (P < 0.005). CONCLUSIONS: Optimized SR-TrueFISP first-pass myocardial perfusion MRI at 3 T has superior image quality compared with SR-TurboFLASH, independent of the myocardial segment analyzed. However, coil sensitivity nonuniformities and dielectric resonance effects cause signal intensity differences between myocardial segments that must be accounted for when interpreting 3 T perfusion studies.
OBJECTIVE: Magnetic resonance imaging (MRI) at 3 T is significantly different than 1.5 T and needs to be optimized due to increased signal-to-noise ratio (SNR) and specific absorption ratio (SAR). This study tests the hypothesis that first-pass myocardial perfusion MRI using saturation recovery (SR)-TrueFISP with parallel imaging is superior to SR-TurboFLASH and a more achievable technique for clinical application at 3 T. MATERIALS AND METHODS: Myocardial perfusion imaging was performed on 12 subjects using SR-TurboFLASH and SR-TrueFISP sequences combined with parallel imaging. Four myocardial slices were acquired and evaluated by image segmentation. Quality of the measurements was determined from SNR, contrast-to-noise ratio (CNR), enhancement-to-noise ratio (ENR), and myocardial perfusion upslope. Data were analyzed using a 2-way ANOVA with imaging method and segment number as the independent variables. RESULTS: SNR, CNR, ENR, and upslope were significantly higher for SR-TrueFISP versus SR-TurboFLASH (P < 0.001). Significant differences in SNR, CNR, ENR, and upslope were found among the myocardial segments (P < 0.005). CONCLUSIONS: Optimized SR-TrueFISP first-pass myocardial perfusion MRI at 3 T has superior image quality compared with SR-TurboFLASH, independent of the myocardial segment analyzed. However, coil sensitivity nonuniformities and dielectric resonance effects cause signal intensity differences between myocardial segments that must be accounted for when interpreting 3 T perfusion studies.
Authors: Yannick Bliesener; Xinran Zhong; Yi Guo; Michael Boss; Ryan Bosca; Hendrik Laue; Caroline Chung; Kyunghyun Sung; Krishna S Nayak Journal: Med Phys Date: 2019-04-15 Impact factor: 4.071