【摘要】 目的:通过测试数字成像设备的X线机管电压和曝光时间稳定性,探讨数字成像摄影条件的选择原则。方法:在证明四台数字X线机mAs稳定性合格的前提下,选择合适的kVp档和时间档,测量其高压不准确度和曝光时间不准确度,并同国家标准进行比较。结果:四种X线机管电压不准确度在各个kVp档上均小于5%;时间不准确度大约在20ms档以上小于5%,在20ms档以下大于5%。结论:应用数字X线机摄影时曝光时间不可选择太小。更多还原

【Abstract】 Objective:To obtain suitable digital radiologic exposure factors of CR and DR by measuring stability of their X-ray tube voltage and exposure time.Methods:Four X-ray units were studied,the actual X-ray tube voltage was orderly measured when pre-setting voltage was 45,60,80,100,120,the actual exposure time was orderly measured when pre-set exposure time was 2,6,40,50,100,500,1000.By comparing actual measured values and pre-set ones,inaccuracy was obtained.Results:For all of four X-ray units,inaccuracy of voltage were less than 5%;inaccuracy of exposure time were less than 5% when pre-set time >20ms,and more than 5% when pre-set time < 20ms.Conclusion:In practice exposure time should keep high level to ensure X-ray unit output steady.更多还原