Objective:To design a device to increase the accuracy of the targeting process and reduce the radiation exposure to both the patients and the medical staff.Methods:We analyzed the inherent problem and designed the Ext...Objective:To design a device to increase the accuracy of the targeting process and reduce the radiation exposure to both the patients and the medical staff.Methods:We analyzed the inherent problem and designed the External Assist Targeting Device(EATD)to assist in the alignment of needle targeting on the desired renal calyx under fluoroscopic guidance.The EATD was designed to allow rapid and precise access to calyces at all angles,with a simple two-step puncture protocol developed for puncturing a target renal calyx.We then tested the device in a pilot human trial with four patients.Results:In experiments with phantom models,the time for successful targeting was reduced by 31%using the device.The mean fluoroscopic time was reduced by 40%.In initial human trial,the puncture time was shortened by 66%and the radiation dose was decreased by 65%compared to free-hand technique.No complication was observed during the trial.Conclusion:The EATD was found to be cost effective,portable,simple to set up,and safe to operate for assisting in the percutaneous nephrolithotomy procedures.Our preliminary tests showed high degree of accuracy in gaining precise access to a targeted renal calyx with much shorter time and lesser radiation dose.The EATD also has the potential to be used to access other organs with precision under fluoroscopic guidance.展开更多
Magnetized target fusion is an alternative method to fulfill the goal of controlled fusion, which combines advan- tages of both magnetic confinement fusion and inertial confinement fusion since its parameter space lie...Magnetized target fusion is an alternative method to fulfill the goal of controlled fusion, which combines advan- tages of both magnetic confinement fusion and inertial confinement fusion since its parameter space lies between the two traditional ways. Field reversed configuration (FFtC) is a good candidate of magnetized targets due to its translatable, compressible, high /3 and high energy density properties. Dynamic formation process of high density FFtC is observed on the YingGuang 1 device for the first time in China. The evolution of a magnetic field is detected with magnetic probes, and the compression process can be clearly seen from images taken with a high-speed multi-frame CCD camera. The process is also studied with two-dimensional magneto hydrodynamic code MPF-2D theoretically, and the results agree well with the experiment. Combining the experimental data and the theoretical analysis, the length of the formed FRC is about 39 cm, the diameter is about 2-2. 7cm, the average density is 1.3× 1016 cm-3, and the average temperature is 137eV.展开更多
文摘Objective:To design a device to increase the accuracy of the targeting process and reduce the radiation exposure to both the patients and the medical staff.Methods:We analyzed the inherent problem and designed the External Assist Targeting Device(EATD)to assist in the alignment of needle targeting on the desired renal calyx under fluoroscopic guidance.The EATD was designed to allow rapid and precise access to calyces at all angles,with a simple two-step puncture protocol developed for puncturing a target renal calyx.We then tested the device in a pilot human trial with four patients.Results:In experiments with phantom models,the time for successful targeting was reduced by 31%using the device.The mean fluoroscopic time was reduced by 40%.In initial human trial,the puncture time was shortened by 66%and the radiation dose was decreased by 65%compared to free-hand technique.No complication was observed during the trial.Conclusion:The EATD was found to be cost effective,portable,simple to set up,and safe to operate for assisting in the percutaneous nephrolithotomy procedures.Our preliminary tests showed high degree of accuracy in gaining precise access to a targeted renal calyx with much shorter time and lesser radiation dose.The EATD also has the potential to be used to access other organs with precision under fluoroscopic guidance.
基金Supported by the Development Foundation of China Academy of Engineering Physics under Grant No 2011B0402009the National Natural Science Foundation of China under Grant Nos 11375163,11575029 and 11175028
文摘Magnetized target fusion is an alternative method to fulfill the goal of controlled fusion, which combines advan- tages of both magnetic confinement fusion and inertial confinement fusion since its parameter space lies between the two traditional ways. Field reversed configuration (FFtC) is a good candidate of magnetized targets due to its translatable, compressible, high /3 and high energy density properties. Dynamic formation process of high density FFtC is observed on the YingGuang 1 device for the first time in China. The evolution of a magnetic field is detected with magnetic probes, and the compression process can be clearly seen from images taken with a high-speed multi-frame CCD camera. The process is also studied with two-dimensional magneto hydrodynamic code MPF-2D theoretically, and the results agree well with the experiment. Combining the experimental data and the theoretical analysis, the length of the formed FRC is about 39 cm, the diameter is about 2-2. 7cm, the average density is 1.3× 1016 cm-3, and the average temperature is 137eV.