School of Health and Society, University of Salford, UK.
School of Health and Society, University of Salford, UK.
Radiography (Lond). 2021 Feb;27(1):215-220. doi: 10.1016/j.radi.2020.10.014. Epub 2020 Nov 9.
Mattresses in the radiology department tend to be an overlooked aspect of imaging equipment. This paper evaluates the radiation attenuation characteristics of mattresses and the effect they have on image quality.
Thirteen mattresses (from new to 20 years of age) were evaluated. Incident air kerma (IAK) was measured in two conditions, with and without mattress over a range of exposure factors using a digital dosimeter. Image quality was assessed by calculating the inverse image quality factor (IQF) using a commercially available phantom (CDRAD) for the same exposure factors. The correlation of age and attenuation and image quality was calculated.
Measured IAK and image quality was affected by the addition of a mattress with older mattresses having greater attenuation; there is a moderate/large correlation (0.38-0.51) between age and IAK. IQF deteriorated with the addition of a mattress but there was no correlation with age (-0.41 to 0.16). Clinically, there is no impact of any mattress in the study as changes to the exposure factors to account for the attenuation are smaller than the increments in mAs available on X-ray equipment.
The results indicate that while the presence of a mattress does impact on transmitted radiation and the quality of the image, the clinical impact is insignificant. Attenuation correlates with age but with no clinical significance. There is no correlation between age and image quality.
Quality control tests for attenuation and impact on image quality are not required in clinical practice. The method could be used by manufacturers to test new materials and mattresses and could provide users with specifications of new products.
放射科的床垫往往是被忽视的成像设备方面。本文评估了床垫的辐射衰减特性及其对图像质量的影响。
评估了 13 个床垫（从新到 20 年）。在两种情况下，使用数字剂量仪在一系列曝光因子下测量有床垫和无床垫时的空气比释动能（IAK）。使用商用体模（CDRAD）计算相同曝光因子的逆图像质量因子（IQF）来评估图像质量。计算了年龄与衰减和图像质量的相关性。
添加床垫会影响测量的 IAK 和图像质量，较旧的床垫衰减更大；年龄与 IAK 之间存在中度/高度相关性（0.38-0.51）。添加床垫会使 IQF 恶化，但与年龄无关（-0.41 至 0.16）。临床方面，研究中没有任何床垫的影响，因为为衰减而调整的曝光因素的变化小于 X 射线设备上可用的 mAs 增量。
结果表明，虽然床垫的存在确实会影响透射辐射和图像质量，但临床影响不大。衰减与年龄相关，但无临床意义。年龄与图像质量之间没有相关性。
衰减和对图像质量影响的质量控制测试在临床实践中不需要。该方法可被制造商用于测试新材料和床垫，并可为用户提供新产品的规格。
