Huda W, Slone R M, Belden C J, Williams J L, Cumming W A, Palmer C K
Department of Radiology, University of Florida College of Medicine, Gainesville 32610-0374, USA.
Radiology. 1996 Apr;199(1):249-52. doi: 10.1148/radiology.199.1.8633153.
To investigate the relationship between radiation exposure and perceived mottle at bedside pediatric chest examinations performed with screen-film and computed radiographic techniques.
In a pediatric intensive care unit, chest radiographs were obtained with both computed radiography (60 radiographs) and a 600-speed screen-film system (14 radiographs). The relative radiation exposure was estimated by using the sensitivity value obtained in the processing of each computed radiograph. Five radiologists assessed the mottle present in the computed radiographs and screen-film images.
For computed radiographs, the perceived level of mottle was inversely related to radiation exposure. For the same radiation exposure, the perceived mottle on computed radiographs was significantly higher than that on screen-film images (P < .001 for small cassettes; P < .01 for large cassettes).
Pediatric computed radiography of the chest requires approximately twice the exposure of a 600-speed screen-film system to attain the same level of mottle.
探讨在床边小儿胸部检查中，使用屏-片技术和计算机X线摄影技术时，辐射暴露与可察觉的斑点之间的关系。
在一家儿科重症监护病房，分别使用计算机X线摄影（60张胸片）和600速屏-片系统（14张胸片）获取胸部X线片。通过使用每张计算机X线片处理过程中获得的敏感度值来估计相对辐射暴露。五名放射科医生评估了计算机X线片和屏-片图像中存在的斑点。
对于计算机X线片，可察觉的斑点水平与辐射暴露呈负相关。在相同的辐射暴露下，计算机X线片上可察觉的斑点明显高于屏-片图像（小暗盒的P <.001；大暗盒的P <.01）。
小儿胸部计算机X线摄影需要大约两倍于600速屏-片系统的曝光量才能达到相同的斑点水平。
