Rosenberg R D, Kelsey C A, Williamson M R, Houston J D, Hunt W C
Department of Radiology, University of New Mexico Health Sciences Center, Albuquerque 87131, USA.
Med Phys. 2001 Aug;28(8):1546-51. doi: 10.1118/1.1386425.
There is potentially more to quality assurance in mammography than the MQSA mandated tests. In this paper we describe a method of capturing individual mammogram technical parameters and the creation of new measures. These include the numbers of images required for each screening examination by technologist, median compression by technologist, and the radiation dose of the examination to the general population of patients.
METHOD/MATERIALS: With this method we describe a semiautomated method of the collection of technical data from mammography exposures. The data that are automatically created by the mammography unit are saved on a computer for later analysis. The method was used on 2738 consecutive screening mammography examinations and 13 621 exposures from one machine. Data were obtained from November 1998 through December 1999.
Using standard methods, the mean glandular dose (MGD) per exposure was 2.62 mGy (SD 1.2). The mean dose per bilateral screening examination was 6.53 mGy (SD 3.07), the median dose was 6.11 mGy, and the dose range was 1.13-34.23 mGy. Rhodium filtration was used for 18% of the exposures. The average and median breast thickness was 4.9 cm. The ACR phantom MGD for this machine was 2.44 mGy at 25 kVp, and 1.97 mGy at 26 kVp. The mean number of exposures for a bilateral mammogram was 4.9, and varied by a technologist from 4.7 to 5.2. The mean compression pressure varied by technologist from 13 to 30 lbs (58-134 N).
The mean dose per mammogram is slightly greater than the ACR phantom dose at 25 kVp. Almost five exposures were necessary for a standard bilateral examination, and this varied by technologist. The compression used also varied by technologist. The semiautomated collection of technical data can aid in maintaining an effective mammography QA program.
乳腺钼靶摄影的质量保证可能不仅仅局限于乳腺影像报告和数据系统（MQSA）规定的检测。在本文中，我们描述了一种获取个体乳腺钼靶摄影技术参数以及创建新指标的方法。这些指标包括技术人员进行每次筛查检查所需的图像数量、技术人员的平均压迫力度以及该检查对全体患者人群的辐射剂量。
方法/材料：通过这种方法，我们描述了一种从乳腺钼靶摄影曝光中收集技术数据的半自动方法。乳腺钼靶摄影设备自动生成的数据会保存在计算机上，以供后续分析。该方法应用于2738例连续的乳腺钼靶筛查检查以及一台设备的13621次曝光。数据收集时间为1998年11月至1999年12月。
采用标准方法，每次曝光的平均腺体剂量（MGD）为2.62毫戈瑞（标准差1.2）。双侧筛查检查的平均剂量为6.53毫戈瑞（标准差3.07），中位剂量为6.11毫戈瑞，剂量范围为1.13 - 34.23毫戈瑞。18%的曝光使用了铑滤过。平均乳房厚度和中位乳房厚度为4.9厘米。该设备在25千伏峰值电压（kVp）时的美国放射学会（ACR）体模MGD为2.44毫戈瑞，在26 kVp时为1.97毫戈瑞。双侧乳腺钼靶摄影的平均曝光次数为4.9次，不同技术人员的曝光次数在4.7至5.2次之间。不同技术人员的平均压迫压力在13至30磅（58 - 134牛顿）之间。
每次乳腺钼靶摄影的平均剂量略高于ACR体模在25 kVp时的剂量。标准的双侧检查大约需要五次曝光，且不同技术人员的曝光次数有所不同。技术人员使用的压迫力度也存在差异。技术数据的半自动收集有助于维持有效的乳腺钼靶摄影质量保证计划。
