From the Department of Radiology and Radiological Science (S.V.T., W.J.R., D.P., S.T.S., M.G.M., M.V.S.).
From the Department of Radiology and Radiological Science (S.V.T., W.J.R., D.P., S.T.S., M.G.M., M.V.S.)
AJNR Am J Neuroradiol. 2019 Jun;40(6):1067-1073. doi: 10.3174/ajnr.A6073. Epub 2019 May 23.
Optimization of pediatric neck CT protocols is of critical importance in order to maintain good diagnostic image quality while reducing the radiation burden. Our aim was to evaluate the image quality of pediatric neck CT studies before and after the implementation of a low radiation dose protocol.
We retrospectively reviewed 179 pediatric neck CT studies, 75 before and 104 after the implementation of low-dose protocols, performed in children 0-16 years of age. The 2 cohorts were divided into 3 age groups, 0-4, 5-9, and 10-16 years. The signal-to-noise ratio was calculated using the axial image through the true vocal folds. Three neuroradiologists assessed the image quality of the same CT scan using a 5-point scoring system. We compared the CT dose index volume, dose-length product, image-quality ratings, and SNR of studies conducted at baseline and with low-dose protocols.
Image-quality ratings were lower in the low-dose than in the baseline cohort in children 10-16 years of age, but not in children 0-4 and 5-9 years of age. The SNR was lower in the low-dose cohort than in the baseline cohort in children 0-4 and 10-16 years of age, but not in children 5-9 years of age. Despite the decrease in image-quality scores in older children, 97% of the studies (73/75) in the baseline cohort and 96% of studies (100/104) in the low-dose cohort were considered of sufficient image quality.
Images acquired with the low-dose CT protocols were deemed to be of sufficient quality for making a clinical diagnosis. Our initial results suggest that there may be an opportunity for further radiation dose reduction without compromising diagnostic image quality using iterative reconstruction algorithms.
为了在保持良好诊断图像质量的同时降低辐射负担，优化儿科颈部 CT 方案至关重要。我们的目的是评估实施低剂量方案前后儿科颈部 CT 研究的图像质量。
我们回顾性分析了 179 例 0-16 岁儿童行颈部 CT 检查的病例，其中 75 例在实施低剂量方案前，104 例在实施后。这两组病例分为 3 个年龄组，0-4 岁、5-9 岁和 10-16 岁。通过真声带的轴向图像计算信噪比。3 名神经放射科医生使用 5 分制评分系统评估同一 CT 扫描的图像质量。我们比较了基线和低剂量方案下的 CT 剂量指数体积、剂量长度乘积、图像质量评分和 SNR。
在 10-16 岁儿童中，低剂量组的图像质量评分低于基线组，但在 0-4 岁和 5-9 岁儿童中则不然。在 0-4 岁和 10-16 岁儿童中，低剂量组的 SNR 低于基线组，但在 5-9 岁儿童中则不然。尽管在年龄较大的儿童中图像质量评分下降，但在基线组的 73/75 例研究中，以及在低剂量组的 100/104 例研究中，97%（73/75）和 96%（100/104）的研究均被认为具有足够的图像质量。
使用低剂量 CT 方案获得的图像被认为足以进行临床诊断。我们的初步结果表明，在不影响诊断图像质量的情况下，使用迭代重建算法可能有机会进一步降低辐射剂量。
