ABSTRACT
@#AIM: To evaluate the difference and consistency of pupillary offset measured by the Pentacam anterior segment analyzer and Keratron Scout corneal topographer.<p>METHODS: Three hundred and eleven patients(604 eyes)who underwent excimer laser in situ keratomileusis from November 2017 to February 2018 were randomly selected. Before surgery, the pupillary offset values were measured by Pentacam and Keratron, and the differences and consistency of the values between the two instruments were compared.<p>RESULTS: The pupillary offset values of the right eyes, left eyes, and both eyes between Pentacam and Keratron were statistically different(<i>P</i><0.05). There were no significant statistical differences in the offset orientations of right eyes, left eyes and both eyes between the two instruments(<i>P</i>>0.05). The 95% consistent line(<i>LoA</i>)of offset value and offset orientation in the right eyes, left eyes and both eyes between the two instruments were -0.11-0.19mm and -157.01°-135.35°, -0.12-0.18mm and -150.16°-158.22°, -0.11-0.19mm and -154.30°-147.10°, respectively. <p>CONCLUSION: The pupillary offset measured by the Pentacam was smaller than that measured by the Keratron, but the difference was within the clinically acceptable range. The accurate pupillary offset can be obtained, and be the mutual reference, correction and supplement in the both instruments.
ABSTRACT
Objective To investigate the Offset values of different applicators in afterloading brachytherapy.Methods Six types of applicators were selected in this study which included stainless steel interstitial needle (Part#083.062),proguide round needle (Part#189.608),proguide sharp needle (Part# 189.601),vaginal multi-channel applicator (Part # 110.800),fletcher CT/MR applicator (Part # 189.745)and henschke titanium applicator (Part#110.437).According to the sources imaging in the fluorography film,the distance of applicators between the first dwell position and the top could be measured.Marker was pasted on the surface of applicator corresponding to the first dwell position.And then the applicator was put into the pelvic phantom for a CT scan.During applicator reconstruction in the treatment planning system,the Offset values of all applicators could be acquired through adjusting the value of offset to superimpose the first dwell and the marker images.On account of the density of plastic material applicators were similar to human tissues,it was difficult to reconstruct the top of the applicator.With the help of stopper or simulation source,the value of offset could be acquired for plastic material applicators.Based on the measurement results,the differences were analyzed among different applicators.Results The Offset values significantly differed among various applicators.The Offset value for stainless steel interstitial needle was-11.4 mm,-4.1 mm for proguide round needle,-3.5 mm for proguide sharp needle,0 mm or-5.0 mm for vaginal multi-channel applicator,-6.5 mm for fletcher CT/MR applicator and-7.5 mm for henschke titanium applicator,respectively.Conclusion To adapt to the rapid development of precise radiotherapy,it is necessary to verify the Offset value in afterloading brachytherapy.
ABSTRACT
Objective@#To investigate the Offset values of different applicators in afterloading brachytherapy.@*Methods@#Six types of applicators were selected in this study which included stainless steel interstitial needle (Part#083.062), proguide round needle (Part#189.608), proguide sharp needle (Part#189.601), vaginal multi-channel applicator (Part#110.800), fletcher CT/MR applicator (Part#189.745) and henschke titanium applicator (Part#110.437). According to the sources imaging in the fluorography film, the distance of applicators between the first dwell position and the top could be measured. Marker was pasted on the surface of applicator corresponding to the first dwell position. And then the applicator was put into the pelvic phantom for a CT scan. During applicator reconstruction in the treatment planning system, the Offset values of all applicators could be acquired through adjusting the value of offset to superimpose the first dwell and the marker images. On account of the density of plastic material applicators were similar to human tissues, it was difficult to reconstruct the top of the applicator. With the help of stopper or simulation source, the value of offset could be acquired for plastic material applicators. Based on the measurement results, the differences were analyzed among different applicators.@*Results@#The Offset values significantly differed among various applicators. The Offset value for stainless steel interstitial needle was -11.4 mm, -4.1 mm for proguide round needle, -3.5 mm for proguide sharp needle, 0 mm or -5.0 mm for vaginal multi-channel applicator, -6.5 mm for fletcher CT/MR applicator and -7.5 mm for henschke titanium applicator, respectively.@*Conclusion@#To adapt to the rapid development of precise radiotherapy, it is necessary to verify the Offset value in afterloading brachytherapy.