Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland.
Eur Radiol. 2013 Oct;23(10):2687-94. doi: 10.1007/s00330-013-2885-z. Epub 2013 May 19.
To determine the value of a metal artefact reduction (MAR) algorithm with iterative reconstructions for dental hardware in carotid CT angiography.
Twenty-four patients (six of which were women; mean age 70 ± 12 years) with dental hardware undergoing carotid CT angiography were included. Datasets were reconstructed with filtered back projection (FBP) and using a MAR algorithm employing normalisation and an iterative frequency-split (IFS) approach. Three blinded, independent readers measured CT attenuation values and evaluated image quality and degrees of artefacts using axial images, multi-planar reformations (MPRs) and maximal intensity projections (MIP) of the carotid arteries.
CT attenuation values of the internal carotid artery on images with metal artefacts were significantly higher in FBP (324 ± 104HU) datasets compared with those reconstructed with IFS (278 ± 114HU; P < 0.001) and with FBP on images without metal artefacts (293 ± 106HU; P = 0.006). Quality of IFS images was rated significantly higher on axial, MPR and MIP images (P < 0.05, each), and readers found significantly less artefacts impairing the diagnostic confidence of the internal carotid artery (P < 0.05, each).
The MAR algorithm with the IFS approach allowed for a significant reduction of artefacts from dental hardware in carotid CT angiography, hereby increasing image quality and improving the accuracy of CT attenuation measurements.
• CT angiography of the neck has proven value for evaluating carotid disease • Neck CT angiography images are often degraded by artefacts from dental implants • A metal artefact reduction algorithm with iterative reconstruction reduces artefacts significantly • Visualisation of the internal carotid artery is improved.
确定迭代重建金属伪影减少（MAR）算法在颈动脉 CT 血管造影中用于牙科硬件的价值。
纳入 24 名接受颈动脉 CT 血管造影检查的带有牙科硬件的患者（其中 6 名为女性；平均年龄 70±12 岁）。使用滤波反投影（FBP）和采用归一化和迭代频率分裂（IFS）方法的 MAR 算法对数据集进行重建。三名经过培训的、独立的阅片者对 CT 衰减值进行测量，并使用颈动脉的轴向图像、多平面重建（MPR）和最大强度投影（MIP）对图像质量和伪影程度进行评估。
FBP （324±104HU）重建图像上带金属伪影的颈内动脉 CT 衰减值明显高于 IFS （278±114HU；P＜0.001）和无金属伪影的 FBP 图像（293±106HU；P=0.006）。轴向、MPR 和 MIP 图像上 IFS 图像的质量评分显著更高（P＜0.05，每次），且阅片者发现内部颈动脉的诊断信心受到的伪影影响明显更小（P＜0.05，每次）。
采用 IFS 方法的 MAR 算法可显著减少颈动脉 CT 血管造影中牙科硬件产生的伪影，从而提高图像质量并改善 CT 衰减测量的准确性。
颈部 CT 血管造影已被证明对评估颈动脉疾病具有价值。
颈部 CT 血管造影图像常因牙科植入物产生的伪影而质量下降。
具有迭代重建的金属伪影减少算法可显著减少伪影。
内部颈动脉的可视化得到改善。
