小乳腺的计算机X线摄影方法探讨

目的探讨小乳腺在计算机X线摄影(CR)中能清晰显示其组织结构的方法。方法分析150份乳腺CR图像的显示情况,发现乳腺结构显示得清晰与否和乳腺的大小有关;用24阶铝梯模拟小乳腺,用不同的投照参数以及不同方法遮挡成像板(IP)直接曝光区进行投照,再用CR系统处理并直接打印出胶片,然后用密度仪分别测量。结果CR中用遮光器遮挡IP板边缘10~15mm宽度或用0.2 mm厚、边长22 mm的正方形铜片遮挡IP板中心位置,都能明显改善铝梯灰阶的显示。同样方法进行实际的小乳腺投照,乳腺的组织结构均能清晰显示。结论在用CR系统进行小乳腺摄影时,用遮光器或薄铜片对处于直接曝光区的检测点进行适当遮挡,能明显改善乳腺组织结构的显示情况。

Computed Radiography of Small Mammary Gland

Objective To discuss a method to show the structure of small mammary gland well by computed radiography(CR).Methods By analyzing 150 radiographs of mammary glands,the results showed that the mammary structure showed well whether or not was depended on the size of mammary gland.Using 24 steps aluminum ladder mimiced the small mammary gland and radiography was taken with various parameters and different imaging plate(IP) shading ways,then processed and printed,after that it was measured by density instrument.Results The display of grey scale of 24 steps aluminum ladder was improved if shading 10~15 mm margin of the IP by collimator or shading the central by a square cuprum plate with 22 mm length and 0.2 mm thickness.Radiography of small mammary gland by the same way was performed and the mammary structure was also showed well.Conclusion Shading the exposing areas properly by collimator or cuprum plate during CR can apparently improve the display of small mammary structure.