Chu Robert Y, Lam Tin, Liang Yongguang
Department of Radiological Sciences, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma 73190, USA.
J Appl Clin Med Phys. 2007 Apr 19;8(2):110-3. doi: 10.1120/jacmp.v8i2.2457.
The location and field size of the incident X-ray beam in panoramic dental radiography cannot be ascertained visually most of the time. However, these parameters are needed for quality control and dosimetry determination. To alleviate this problem, we tested GafChromic XR-QA film on two panoramic systems. For each system, we used the length of a cross-sectional image of the incident beam and the exposure measurement with a pencil ion chamber to compute the dose-area product. The result was confirmed by direct analysis of a dose distribution on a film. Placement of the ion chamber was determined by the latter images. The GafChromic XR-QA version of radiochromic film has thus been demonstrated to usefully complement a pencil ion chamber in the testing of a panoramic radiography system.
在全景牙科放射ography中，大多数时候无法通过视觉确定入射X射线束的位置和野大小。然而，这些参数对于质量控制和剂量测定是必需的。为了缓解这个问题，我们在两个全景系统上测试了GafChromic XR-QA胶片。对于每个系统，我们使用入射束横截面图像的长度和铅笔电离室的曝光测量来计算剂量面积乘积。结果通过对胶片上剂量分布的直接分析得到证实。电离室的放置由后者的图像确定。因此，已证明GafChromic XR-QA版放射变色胶片在全景放射成像系统测试中可有效补充铅笔电离室。
