Mateya C F, Claycamp H G
University of Pittsburgh, Department of Environmental and Occupational Health, PA 15238, USA.
Health Phys. 1997 Jun;72(6):842-7. doi: 10.1097/00004032-199706000-00003.
Organ dose equivalents were measured in a humanoid phantom in order to estimate effective dose equivalent (H(E)) and effective dose (E) from low-energy x rays and in the presence or absence of a protective lead apron. Plane-parallel irradiation conditions were approximated using direct x-ray beams of 76 and 104 kVp and resulting dosimetry data was adjusted to model exposures conditions in fluoroscopy settings. Values of H(E) and E estimated under-shielded conditions were compared to the results of several recent studies that used combinations of measured and calculated dosimetry to model exposures to radiologists. While the estimates of H(E) and E without the lead apron were within 0.2 to 20% of expected values, estimates based on personal monitors worn at the (phantom) waist (underneath the apron) underestimated either H(E) or E while monitors placed at the neck (above the apron) significantly overestimated both quantities. Also, the experimentally determined H(E) and E were 1.4 to 3.3 times greater than might be estimated using recently reported "two-monitor" algorithms for the estimation of effective dose quantities. The results suggest that accurate estimation of either H(E) or E from personal monitors under conditions of partial body exposures remains problematic and is likely to require the use of multiple monitors.
为了估计低能X射线产生的有效剂量当量（H(E)）和有效剂量（E），并研究在有或没有防护铅围裙的情况下，在人形体模中测量了器官剂量当量。使用76和104 kVp的直接X射线束近似平面平行照射条件，并对所得剂量学数据进行调整，以模拟荧光透视设置中的照射条件。将在无屏蔽条件下估计的H(E)和E值与最近几项研究的结果进行了比较，这些研究使用测量和计算剂量学的组合来模拟放射科医生的照射情况。虽然没有铅围裙时H(E)和E的估计值在预期值的0.2%至20%范围内，但基于（体模）腰部（围裙下方）佩戴的个人监测器的估计值低估了H(E)或E，而放置在颈部（围裙上方）的监测器则显著高估了这两个量。此外，实验确定的H(E)和E比使用最近报道的用于估计有效剂量量的“双监测器”算法估计的值大1.4至3.3倍。结果表明，在局部身体照射条件下，从个人监测器准确估计H(E)或E仍然存在问题，可能需要使用多个监测器。
