Background：Nonfluoroscopic three-dimensional electroanatomical system is widely used nowadays,but X-ray remains indispensable for complex electrophysiology procedures.This study aimed to evaluate the value of optimiz...Background：Nonfluoroscopic three-dimensional electroanatomical system is widely used nowadays,but X-ray remains indispensable for complex electrophysiology procedures.This study aimed to evaluate the value of optimized parameter setting and different projection position to reduce X-ray radiation dose rates.Methods：From June 2013 to October 2013,105 consecutive patients who underwent complex ablation were enrolled in the study.After the ablation,the radiation dose rates were measured by two different settings （default setting and optimized setting） with three projection positions （posteroanterior [PA] projection;left anterior oblique [LAO] 30° projection;and LAO 45° projection）.The parameter of preset voltage,pulse width,critical voltage,peak voltage,noise reduction,edge enhancement,pulse rate,and dose per frame was modified in the optimized setting.Results：The optimized setting reduced radiation dose rates by 87.5％ （1.7 Gy/min vs.13.6 Gy/min,P ＜ 0.001） in PA,87.3％ （2.5 Gy/min vs.19.7 Gy/min,P＜0.001） in LAO 30°,85.9％ （3.1 Gy/min vs.22.1 Gy/min,P ＜ 0.001） in LAO 45°.Increase the angle of projection position will increase the radiation dose rate.Conclusions：We can reduce X-ray radiation dose rates by adjusting the parameter setting of X-ray system.Avoiding oblique projection of large angle is another way to reduce X-ray radiation dose rates.展开更多
A position sensor based on grating projection with spatial filtering and polarization modulation is presented. A grating is projected onto the object to be measured through a 4f optical system with a spatial filter. A...A position sensor based on grating projection with spatial filtering and polarization modulation is presented. A grating is projected onto the object to be measured through a 4f optical system with a spatial filter. After reflected by the object, the grating projection is imaged on a detection grating through another 4f optical system to form moiré fringes, The polarization modulated moiré signal is detected to obtain the position information of the object. In the position sensor, the moiré signal varies sinusoidally with the position of object. The measurement is independent of the incident intensity on the projection grating and the reflectivity of the object to be measured, In experiments, the effectiveness of the position sensor is proved, and the root mean square （RMS） error at each measurement position is less than 13 nm.展开更多
文摘Background：Nonfluoroscopic three-dimensional electroanatomical system is widely used nowadays,but X-ray remains indispensable for complex electrophysiology procedures.This study aimed to evaluate the value of optimized parameter setting and different projection position to reduce X-ray radiation dose rates.Methods：From June 2013 to October 2013,105 consecutive patients who underwent complex ablation were enrolled in the study.After the ablation,the radiation dose rates were measured by two different settings （default setting and optimized setting） with three projection positions （posteroanterior [PA] projection;left anterior oblique [LAO] 30° projection;and LAO 45° projection）.The parameter of preset voltage,pulse width,critical voltage,peak voltage,noise reduction,edge enhancement,pulse rate,and dose per frame was modified in the optimized setting.Results：The optimized setting reduced radiation dose rates by 87.5％ （1.7 Gy/min vs.13.6 Gy/min,P ＜ 0.001） in PA,87.3％ （2.5 Gy/min vs.19.7 Gy/min,P＜0.001） in LAO 30°,85.9％ （3.1 Gy/min vs.22.1 Gy/min,P ＜ 0.001） in LAO 45°.Increase the angle of projection position will increase the radiation dose rate.Conclusions：We can reduce X-ray radiation dose rates by adjusting the parameter setting of X-ray system.Avoiding oblique projection of large angle is another way to reduce X-ray radiation dose rates.
文摘A position sensor based on grating projection with spatial filtering and polarization modulation is presented. A grating is projected onto the object to be measured through a 4f optical system with a spatial filter. After reflected by the object, the grating projection is imaged on a detection grating through another 4f optical system to form moiré fringes, The polarization modulated moiré signal is detected to obtain the position information of the object. In the position sensor, the moiré signal varies sinusoidally with the position of object. The measurement is independent of the incident intensity on the projection grating and the reflectivity of the object to be measured, In experiments, the effectiveness of the position sensor is proved, and the root mean square （RMS） error at each measurement position is less than 13 nm.
