DR组织均衡技术在低剂量鼻骨侧位X射线摄影中的应用

目的探寻在鼻骨侧位X射线摄影中利用数字化X射线摄影(DR)组织均衡技术获取满足诊断需要的图像并降低患者辐射剂量的研究。方法利用人体模型进行常规的鼻骨侧位摄影,然后固定千伏值,在原有的mAs值上分别降低0.4、0.8、1.2 mAs进行摄片,再将降低剂量的图像采用DR组织均衡技术进行处理,比较不同图像对于满足诊断的需要和患者所接受的辐射剂量。结果常规摄影技术得到的图像需反复调节不同的窗宽、窗位才能显示密度、厚度不同的鼻骨与软组织;降低0.4、0.8 mAs,虽然图像的空间分辨率降低,但是采用DR组织均衡技术可在同一幅图像上清晰显示鼻骨与邻近软组织结构,同时降低患者的辐射剂量;降低1.2 mAs,不但图像的空间分辨率降低,而且无法采用DR组织均衡技术使图像达到满足诊断需要。结论采用DR组织均衡技术不仅能将密度、厚度不同的鼻骨及邻近软组织在同一副图像上清晰显示,而且能够有效降低患者的辐射剂量。

Application of digital X-ray photography tissue equalization technology in low-dose nasal bone lateral X-ray photography

Objective To investigate the feasibility of application of digital X-ray photography tissue equalization technology in low-dose nasal bone lateral X-ray photography,and explore the optimal radiation dose that satisfies the diagnostic requirements.Methods The conventional nasal bone lateral photography of body model was performed.With fixed kilovolt(kV) value,the original mAs value was reduced by 0.4 mAs,0.8 mAs and 1.2 mAs,respectively.Then,the images obtained with the reduced doses were processed by tissue equalization technology and the optimal radiation dose for the diagnostic requirements was analyzed.Results The window width and window level of the images obtained from conventional photography needed to be adjusted in order to show the density and thickness of various nasal bones and soft tissues.Although the spatial resolution of the image was reduced at decrease of 0.4 mAs and 0.8 mAs,the image of the nasal bone and adjacent soft tissue structures could be clearly identified after adjusted by the tissue equalization technique.However,the spatial resolution of the image was reduced too much at decrease of 1.2 mAs,that could not satisfied the diagnostic requirement even after adjusted by tissue equalization technology.Conclusion It is demonstrated that the tissue equalization technology could enhance the density and thickness of various nasal bone and adjacent soft tissue structures and thus could help reduce the radiation exposure to patients.