Herrera M, Moore R, Justich E, Castaneda-Zuniga W R, Amplatz K
Rofo. 1982 Dec;137(6):711-7. doi: 10.1055/s-2008-1056284.
The conventional approach to the removal of secondary radiation in chest radiography is by using an air gap or a radiographic grid. However, grids become ineffective at high kVp levels. This study evaluated efficient scatter removal by radiographic scanography versus the conventional technique. Nylon spheres simulating lung nodules were attached to a standard radiographic thorax phantom and to a special chest phantom of our own design. Conventional and scanographic films were made of the phantoms using the same conditions. The films were read in a double-blind fashion. The results indicated that scanograms permitted appreciation of the simulated nodules over the lungs better than did the conventional films, particularly at higher kVp levels. However, the marked increase of contrast resulted in an underpenetration of the mediastinum. If properly penetrated, the lung fields were overexposed, which resulted in a decrease of the detectability of lesions in spite of a higher normalized contrast. Scanography is a promising technique for improving the detection rate of lung nodules on chest films, provided that means can be found to penetrate the mediastinum without overexposing the lungs.
胸部X线摄影中去除二次辐射的传统方法是使用空气间隙或X线摄影栅。然而，在高千伏峰值（kVp）水平下，X线摄影栅会失效。本研究评估了与传统技术相比，扫描X线摄影在有效去除散射方面的效果。模拟肺结节的尼龙球附着在标准的胸部X线摄影体模和我们自行设计的特殊胸部体模上。在相同条件下，使用体模制作传统和扫描X线摄影胶片。胶片以双盲方式进行阅片。结果表明，扫描X线片比传统胶片能更好地显示肺内模拟结节，尤其是在较高kVp水平时。然而，对比度的显著增加导致纵隔穿透不足。如果穿透适当，肺野会过度曝光，尽管归一化对比度较高，但仍会导致病变可检测性降低。如果能够找到在不使肺部过度曝光的情况下穿透纵隔的方法，扫描X线摄影是一种有望提高胸部X线片上肺结节检出率的技术。
