Department of Radiology, Division of Pediatric Radiology, Medical University of Graz, Austria.
Eur J Radiol. 2013 Jul;82(7):1043-9. doi: 10.1016/j.ejrad.2011.11.041. Epub 2012 Jan 9.
Today CT represents about 10% of all ionizing radiation based imaging modalities, but delivers more than 50% of the total collective dose for diagnostic imaging. Compared to adults the radiation sensitivity of children is considerable higher than in adults. Additionally children differ from adults--factors like body size, mass, density, proportions as well as metabolism have to be mentioned. Children grow and mature--all this components have to be mapped in examination protocols by Pediatric Radiology. The total dose of a CT examination depends on the settings of several factors such as the scout view, the scan length, exposure settings including automated exposure control, type of scanning (single slice, helical, volume mode), slice thickness, pitch values as well as on image reconstruction parameters. If intravenous contrast media injection is needed bolus tracking or timing represents another source of radiation. The aim of the paper is to present and discuss all aspects of defining a pediatric age and query adapted CT protocol particularly concerning all dose relevant factors in pediatric CT and their adjustment in children. Moreover hints are given concerning optimization of intravenous contrast media injection as well as special (low dose) imaging protocols.
今天，CT 约占所有基于电离辐射的成像方式的 10%，但它为诊断成像提供了超过 50%的总集体剂量。与成年人相比，儿童对辐射的敏感性要比成年人高得多。此外，儿童与成年人不同——必须提到身体大小、体重、密度、比例以及新陈代谢等因素。儿童在成长和成熟——所有这些因素都必须在儿科放射学的检查方案中进行映射。CT 检查的总剂量取决于几个因素的设置，例如扫描前视图、扫描长度、曝光设置（包括自动曝光控制）、扫描类型（单层、螺旋、容积模式）、层厚、螺距值以及图像重建参数。如果需要静脉注射造影剂，那么团注追踪或定时则是另一个辐射源。本文的目的是介绍和讨论定义儿科年龄和查询适应 CT 协议的所有方面，特别是涉及儿科 CT 中所有与剂量相关的因素及其在儿童中的调整。此外，还给出了有关静脉注射造影剂优化以及特殊（低剂量）成像方案的提示。
