Résumé
Objective To compare image quality and radiation dose of the new imaging plate (IP) with the used IP on computed radiography (CR),and to investigate the using principle in the two kinds of IP. Methods The dark noise, uniformity and erasure thoroughness of the new and the used IP were measured respectively.Based on threshold contrast-detail detectability(TCCD) technique,the phantom T0.16 photography was done at 75 kV,and with the two kinds of IP respectively.Three observers scored each image sequence using double blind method,calculated the threshold detection index (HT).The volunteers were randomly divided into three groups:the knee joint group,the chest group and the lumbar group.Each group had 50 cases and checked with the same condition as the phantom.Three radiologists using double blind method evaluated the imaging quality of knee joint,chest and lumbar.Results The physical characteristic indexes of the new and the used IP were similar to each other.Under the same condition,the detection ability of the new IP was better than that of the used one.When the dose of exposure was raised about 20%,the detection ability of the used IP was close to that of the new one.Conclusions The dose of exposure can be raised to keep the same imaging quality with the increase times of IP used.The detection ability of IP can decrease with the same dose as before,and the image quality decreases too.
Résumé
Objective To summarize the methods of in-state maintenance of KODAK CR-400PLUS so that to improve the reliabilityof the equipment.Methods The concrete plans about in-state maintenance on the KODAK CR-400PLUS under the guidelines ofin-state maintenance in combination with the practice conditions were established that to ensure the reliable work of CR.Results Themalfunction rate of CR was decreased and the goal of monitoring the performance degradation degree of the key parts was achieved.Conclusion In-state maintenance is effectively in improving the reliability of CR.
Résumé
Objective To measure the imaging parameters including the values of r(r),latitude(L),sensitivity(S)etc of imaging plate of CR by experiments.Methods The double-exposed method of lead steps was utilized to determine the imaging parameters of imaging plates. Results All the parameters of new IPs were suitable to practice and in the right range of clinical radiographic applications. The sensitivity(S) , however, was not at its optimal point at the beginning of the utilization, it would take certain time.Conclusion It would improve the medical image quality to use the changing parameters of CR correctly.
Résumé
Objective To summarize the quality control method of the SOLO CR system running in high efficient-reliable-stablestatus and to obtain the high quality digital imaging.Methods In order to keep the system operating normally,we make the detail plan ofquality control in combination with practical status such as working status and frequency of use,and implement properly maintenance andrepairing for 3 AGFA ADC SOLO CR.Results To ensure the 3 CR system operating normally and steadily,and achieve good results asexpected in 2 years.Conclusion The suitable and effective quality control is necessary.It provides the reliable ensuring for outputting high quality digital imaging.