Craven C M, Naik K S, Blanshard K S, Batchelor A G, Spencer J A
Department of Radiology, St James's University Hospital, Leeds, UK.
Br J Radiol. 1995 Jul;68(811):724-30. doi: 10.1259/0007-1285-68-811-724.
21 infants with craniosynostosis were studied with a new three-dimensional (3D) computed tomography (CT) methodology. We describe technique optimization using multiple spiral data acquisitions with low dose (85 mAs) technique. One caudal volume of 3 mm slice thickness was obtained with a further two volumes of 1 mm slice thickness at the vertex. Image reconstruction of spiral raw data allowed overlapping 3 mm sections to be generated without the dose increase that would result from conventional axial CT scanning. We illustrate common technical artefacts of 3D CT and explain their cause and solution. A dramatic dose reduction to the lens was achieved with no loss in 3D image quality. Lens dose was 8.91 mSv compared with 24.6 mSv using the standard paediatric head technique.
采用一种新的三维(3D)计算机断层扫描(CT)方法对21例患有颅缝早闭的婴儿进行了研究。我们描述了使用低剂量(85 mAs)技术进行多次螺旋数据采集的技术优化。在尾侧获得了一层3 mm层厚的容积数据,在头顶又获得了两层1 mm层厚的容积数据。螺旋原始数据的图像重建能够生成重叠的3 mm断面图像,而不会像传统轴向CT扫描那样导致剂量增加。我们展示了3D CT常见的技术伪影,并解释了其成因及解决方法。在不损失3D图像质量的情况下,晶状体的剂量大幅降低。晶状体剂量为8.91 mSv,而使用标准儿科头部扫描技术时为24.6 mSv。