Department of Medical Imaging, The Prince Charles Hospital, Chermside, Queensland, Australia.
Queensland University of Technology, Faculty of Health, Brisbane, Queensland, Australia.
J Med Radiat Sci. 2023 Sep;70(3):247-253. doi: 10.1002/jmrs.689. Epub 2023 Jun 7.
A current gap identified in medical imaging (MI) literature is a standardised approach to bilateral hand examinations. This examination performed concurrently or unilaterally results in different effects on radiation dose and image quality, both of which are important to the diagnostic and follow-up imaging of rheumatoid arthritis (RA) patients.
An experimental study was undertaken using anthropomorphic hand phantoms at the Queensland University of Technology (QUT) MI Simulation laboratory. Images of the hand were acquired individually and then concurrently with both hands together. Radiation dose was calculated by observing dose area product (DAP) reading on a digital radiography system, with the additional use of an exposure metre as a secondary data collection method. Image quality was quantified through measuring distortion caused by beam divergence, by exploring the separation of two metal rings fixed to the hand phantom.
The overall radiation dose was higher for the unilateral technique by 10.15% at the digital radiography system console and 11.96% recorded by the exposure metre. In the second part of the experiment, the unilateral technique produced 0 mm of distortion when the phantom was positioned in the central part of the beam. The concurrent technique demonstrated an average of 3.65 mm of distortion, when both hands were positioned with the central part of the beam between them.
The unilateral technique should be performed for bilateral hand examinations. The increase in distortion from the concurrent technique is clinically significant, as the diagnostic grading of RA is measured in millimetre increments. The additional overall examination dose is minimal when compared to the improvement in image quality.
目前在医学影像学（MI）文献中存在一个空白，即缺乏一种标准化的双手检查方法。无论是双手同时还是单侧进行检查，都会对辐射剂量和图像质量产生不同的影响，而这两者对于类风湿关节炎（RA）患者的诊断和随访成像都非常重要。
本研究在昆士兰科技大学（QUT）MI 模拟实验室使用人体手部模型进行了一项实验研究。分别对单手和双手同时进行图像采集。通过观察数字射线照相系统上的剂量面积乘积（DAP）读数来计算辐射剂量，同时还使用曝光计作为辅助数据收集方法。通过测量由于射束发散引起的失真来量化图像质量，方法是探索固定在手部模型上的两个金属环之间的分离。
在数字射线照相系统控制台，单侧技术的总辐射剂量比双侧技术高 10.15%，而曝光计记录的剂量高 11.96%。在实验的第二部分中，当手部模型位于射束中心部分时，单侧技术产生了 0mm 的失真。当双手位于射束中心部分之间时，双手同时检查技术平均产生 3.65mm 的失真。
对于双手检查，应采用单侧技术。与同时检查技术相比，单侧技术产生的失真增加具有临床意义，因为 RA 的诊断分级是以毫米为单位进行测量的。与图像质量的提高相比，整体检查剂量的增加微不足道。
