1.Comparison of values of iDose4 iterative reconstruction and filtered back projection reconstruction for coronary CT angiography
Peiguo LIU ; Xu YI ; Jingjin LI ; Yujun WANG ; Yan HAN ; Zhigang SU ; Xingang NIU
Chinese Medical Equipment Journal 2017;38(5):79-81,91
Objective To explore the value of iDose4 iterative reconstruction for coronary CT angiography (CCTA).Methods Totally 124 coronary heart disease patients underwent iDose4 iterative reconstruction and filtered back projection (FBP) reconstruction,of whom,56 ones with BMI not less than 20 kg/m2 were put into No.1 iteration group using 135 kV tube voltage and 68 ones with BMI less than 20 kg/m2 were into No.2 iteration group using 110 kV tube voltage.FBP reconstruction was executed with 110 kV tube voltage.Comparison analyses were carried out on signal noise ratio (SNR),contrast to noise ratio (CNR) and image quality.Results There were significant differences between the values of SNR,radiation dose and image quality in No.1 iteration group and FBP group (P<0.05).Statistical differences were also found between the values of CNR and radiation dose in No.2 iteration group and FBP group,while there were no obvious differences between the values of SNR and image quality in the above two groups (P<0.05).Conclusion Low-voltage iDose reconstruction gains advantages in radiation dose and image quality during 64-slice CCTA,and thus is worthy promoting clinically.
2.Human muscle fatigue monitoring method and its application for exoskeleton interactive control.
Huiqi NIU ; Bi ZHANG ; Ligang LIU ; Yiwen ZHAO ; Xingang ZHAO
Journal of Biomedical Engineering 2023;40(4):654-662
Aiming at the human-computer interaction problem during the movement of the rehabilitation exoskeleton robot, this paper proposes an adaptive human-computer interaction control method based on real-time monitoring of human muscle state. Considering the efficiency of patient health monitoring and rehabilitation training, a new fatigue assessment algorithm was proposed. The method fully combined the human neuromuscular model, and used the relationship between the model parameter changes and the muscle state to achieve the classification of muscle fatigue state on the premise of ensuring the accuracy of the fatigue trend. In order to ensure the safety of human-computer interaction, a variable impedance control algorithm with this algorithm as the supervision link was proposed. On the basis of not adding redundant sensors, the evaluation algorithm was used as the perceptual decision-making link of the control system to monitor the muscle state in real time and carry out the robot control of fault-tolerant mechanism decision-making, so as to achieve the purpose of improving wearing comfort and improving the efficiency of rehabilitation training. Experiments show that the proposed human-computer interaction control method is effective and universal, and has broad application prospects.
Humans
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Exoskeleton Device
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Muscle Fatigue
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Muscles
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Algorithms
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Electric Impedance