Jans R G, Butler P F, McCrohan J L, Thompson W E
Radiology. 1979 Jul;132(1):197-200. doi: 10.1148/132.1.197.
Results of the Breast Exposure: Nationwide Trends (BENT) study are presented. In this study, data were collected from 42 states and several other jurisdictions and the number of facilities found to have unusually high or low exposures during mammography was determined. Surveyors trained by representatives of the Bureau of Radiological Health then worked with these facilities to determine the source of the problem and recommend corrective measures. Contrast was found to be reduced by high "inherent" filtration, high kVp, or inappropriate imaging conditions, while resolution was impaired by excessive exposure time, as well as inappropriate imaging conditions. These and other problems are discussed and correlated with image quality.
全国趋势（BENT）研究的结果。在这项研究中，从42个州和其他几个司法管辖区收集了数据，并确定了在乳腺X线摄影期间曝光异常高或低的设施数量。由放射卫生局代表培训的测量员随后与这些设施合作，以确定问题的根源并推荐纠正措施。发现高“固有”过滤、高千伏峰值或不适当的成像条件会降低对比度，而过长的曝光时间以及不适当的成像条件会损害分辨率。讨论了这些问题和其他问题，并将其与图像质量相关联。
