Dobbins J T, Rice J J, Goodman P C, Patz E F, Ravin C E
Department of Radiology, Duke University Medical Center, Durham, NC 27710.
Radiology. 1993 Apr;187(1):55-63. doi: 10.1148/radiology.187.1.8451437.
The authors describe a variable compensation (VC) technique in which an x-ray equalizer and a computed radiography system are used. The VC technique allows retrospective alteration of equalized chest appearance with maintenance of improved signal-to-noise ratio in dense regions. Two imaging plates are used: one upstream of the patient to record the incident beam profile and one down-stream to record the equalized image. Subtraction of a weighted version of the upstream image from the down-stream image permits alteration of the appearance of the VC image, from the extremes of stimulated-unequalized to highly equalized. VC image appearance was optimized with a real-time workstation. The quality of VC images obtained in 33 patients was evaluated by three chest radiologists. Mediastinal appearance was better on VC equalized images than on conventional screen-film images. The stimulation of the appearance of a conventional radiograph with VC proved useful in interpretation of lung appearances on equalized radiographs.
作者描述了一种可变补偿（VC）技术，该技术使用了一个X射线均衡器和一个计算机X线摄影系统。VC技术允许对均衡后的胸部影像进行回顾性改变，同时在致密区域保持改善的信噪比。使用两块成像板：一块在患者上游记录入射光束轮廓，另一块在下游记录均衡后的图像。从下游图像中减去上游图像的加权版本，可以改变VC图像的外观，从极端的刺激不均衡到高度均衡。通过实时工作站对VC图像外观进行了优化。三位胸部放射科医生对33例患者获得的VC图像质量进行了评估。纵隔在VC均衡图像上的表现优于传统的屏-片图像。事实证明，用VC刺激传统X线片的外观有助于在均衡X线片上解读肺部表现。
