马伟
中国医学科学院阜外医院 放射科
Background:It is unclear whether tube voltage influences the measurement of perfusion parameters. The present study sought to evaluate the influence of tube voltage change on myocardial blood flow (MBF) measurements in dynamic computed tomography myocardial perfusion imaging (CTP).Methods and Results:Seven swine [mean weight 55.8 kg ± 1.6 (standard deviation)] underwent rest and stress dynamic CTP with tube voltages of 100 and 70 kV. The image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), radiation dose and MBF value were compared. The 70 kV images had higher CT attenuation and higher image noise (27.9 ± 2.4 vs. 21.5 ± 1.9, P < 0.001) than the 100 kV images, resulting in a higher SNR (20.5 ± 1.6 vs. 15.6 ± 1.8, P < 0.001) and CNR (17.6 ± 1.5 vs. 12.4 ± 1.7, P < 0.001). Compared to the use of conventional 100 kV, 70 kV yielded an approximately 64.6% radiation dose reduction while generating comparable MBF values, both at rest (88.3 ± 14.9 ml/100 g/min vs. 85.6 ± 17.4 ml/100 g/min, P = 0.21) and stress (101.4 ± 21.5 ml/100 g/min vs. 99.6 ± 21.4 ml/100 g/min, P = 0.58) states.Conclusion:Dynamic CTP using 70 kV instead of 100 kV does not substantially influence the MBF value but significantly reduces the radiation dose. Additional research is required to investigate the clinical significance of this change.
Frontiers in cardiovascular medicine 2022
Objective: To determinate the range of quantitative myocardial perfusion parameters (MBF, MBV) in subjects without coronary artery lesions by dynamic computed tomography myocardial perfusion imaging (CTP). Methods: Subjects with occasional chest tightness or family history of coronary artery disease coming to Fuwai Hospital underwent coronary computed tomography angiography (CCTA) were prospectively enrolled. A total of 34 subjects [mean age (50±7) years, range from 33 to 65 years; 15 male and 19 female] were enrolled. Coronary lesions were not confirmed in any subjects using CCTA and volunteered for stress and rest dynamic CTP examination. MBF and MBV values were calculated in each myocardial segment using a 17-segment model. The global ranges of MBF and MBV were analyzed, and the gender variability and regional variability were compared. Results: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g, respectively. The absolute and resolute reserves of MBF and MBV [(102.8±41.5) ml·100 g-1·min-1, 107.7%±52.5%; (9.3±5.2) ml/100 g, 62.1%±47.4%] were highest in the right coronary artery territory, but without any significant differences. The stress MBF and absolute reserve of MBF in females were higher than those of males [(228.6±39.9) ml·100 g-1·min-1, (113.3±46.2) ml·100 g-1·min-1; (192.8±33.4) ml·100 g-1·min-1, (77.0±41.2) ml·100 g-1·min-1] (both P<0.05). The MBF resolute reserve, rest MBV, stress MBV and MBV absolute and resolute reserves were higher in females, but without significant differences (all P>0.05). Conclusion: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g. The MBF under stress perfusion and MBF absolute reserve of females are higher than those of males.
Zhonghua yi xue za zhi 2021
