Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Road, Suite 302, Durham, NC, 27705, USA.
Medical Physics Graduate Program, Duke University, Durham, NC, USA.
Pediatr Radiol. 2021 May;51(5):800-810. doi: 10.1007/s00247-020-04909-5. Epub 2021 Jan 6.
Managing patient radiation dose in pediatric computed tomography (CT) examinations is essential. Some organizations, most notably Image Gently, have suggested techniques to lower dose to pediatric patients and mitigate risk while maintaining image quality.
We sought to validate whether institutions are observing Image Gently guidelines in practice.
Dose-relevant data from 663,417 abdomen-pelvis and chest CT scans were obtained from 53 facilities. Patients were assigned arbitrary age cohorts with a minimum size of n=12 patients in each age group, for statistical purposes. All pediatric (<19 years old) cohorts at a given facility were compared to the adult cohort by a Kruskal-Wallis test for each of the four scan parameters - (1) x-ray tube kilovoltage (kV), (2) tube-current-by-exposure-time product (tube mAs), (3) scan pitch and (4) tube rotation time - to assess whether the distribution of values in the pediatric cohorts differed from the adult cohort. The same was repeated with volume CT dose index (CTDI) and size-specific dose estimate (SSDE) to assess whether pediatric cohorts received less dose than adult cohorts. A P-value of <0.05 was deemed significant.
Across the 150 pediatric cohorts, 134 had scan parameters that were more child-sized than their adult counterparts. In 128 of these 134 pediatric cohorts, the CTDI was less than the adult counterpart. In 111 of these 128 pediatric cohorts, the SSDE was less than the adult counterpart.
The study reaffirms that in practice, Image Gently's suggestions of lowering tube mAs and peak kilovoltage are commonly employed and effective at reducing pediatric CT dose.
管理儿科计算机断层扫描(CT)检查中的患者辐射剂量至关重要。一些组织,尤其是 Image Gently,已经提出了降低儿科患者剂量和降低风险同时保持图像质量的技术。
我们旨在验证机构在实践中是否遵守了 Image Gently 指南。
从 53 个设施中获取了 663417 例腹部-骨盆和胸部 CT 扫描的剂量相关数据。为了统计目的,将患者分配到任意年龄组,每个年龄组至少有 12 名患者。对于每个扫描参数 - (1) X 射线管千伏 (kV),(2) 管电流-曝光时间乘积 (管 mAs),(3) 扫描螺距和 (4) 管旋转时间 - 对于给定设施的所有儿科 (<19 岁) 队列,通过 Kruskal-Wallis 检验与成人队列进行比较,以评估儿科队列中值的分布是否与成人队列不同。对于体积 CT 剂量指数 (CTDI) 和大小特异性剂量估计 (SSDE) 也进行了同样的重复,以评估儿科队列是否比成人队列接受的剂量更少。P 值<0.05 被认为具有统计学意义。
在 150 个儿科队列中,有 134 个扫描参数比成人队列更符合儿童尺寸。在这 134 个儿科队列中的 128 个中,CTDI 小于成人对照组。在这 128 个儿科队列中的 111 个中,SSDE 小于成人对照组。
该研究再次证实,在实践中,Image Gently 建议降低管 mAs 和峰值千伏是常用的,并且可以有效地降低儿科 CT 剂量。