Respiratory motion artifacts on PET emission images obtained using CT attenuation correction on PET-CT
Respiratory motion artifacts on PET emission images obtained using CT attenuation correction on PET-CT
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DOI：
10.1007/s00259-002-1024-x
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发表时间：
2003-04-01
影响因子：
9.1
通讯作者：
Wahl, RL
中科院分区：
文献类型：
--
作者：
Osman, MM;Cohade, C;Wahl, RL
PET-CT扫描仪允许从CT生成透射图。如果两种衰减校正方法之间存在呼吸状态差异，则使用CT衰减校正（CTAC）代替锗-68衰减校正（Ge AC）可能会导致重建发射图像上的伪影。本研究的目的是评价临床患者PET-CT中经CT衰减校正的PET图像中可能的呼吸运动伪影（RMA）。使用Discovery LS PET-CT系统对50例已知或疑似恶性肿瘤的连续患者（23例男性，27例女性;平均年龄58.2岁）进行PET-CT扫描。自由潮式呼吸期间获得的CTAC和Ge AC传输数据均用于校正PET发射图像。在CTAC图像上观察到但在Ge AC图像上未观察到的肺和横膈膜界面处的冷伪影（被认为是由于呼吸运动（RMA）所致）以四分量表进行定性评价（0，无伪影; 1，轻度伪影; 2，中度伪影; 3，重度伪影）。还测量了RMA的身高。在84%的PET-CT图像采集中观察到平行于肺/横膈界面处横膈圆顶的电流冷伪影，在Ge-68校正图像中未观察到;然而，这些伪影很少严重。总之，在我们的大多数患者中发现了不同程度的RMA，即肺/横膈界面处的曲线冷区，但这些患者的诊断没有问题。
PET-CT scanners allow generation of transmission maps from CT. The use of CT attenuation correction (CTAC) instead of germanium-68 attenuation correction (Ge AC) might be expected to cause artifacts on reconstructed emission images if differences in respiratory status exist between the two methods of attenuation correction. The aim of this study was to evaluate for possible respiratory motion artifacts (RMA) in PET images attenuation corrected with CT from PET-CT in clinical patients. PET-CT scans were performed using a Discovery LS PET-CT system in 50 consecutive patients (23 males, 27 females; mean age 58.2 years) with known or suspected malignancy. Both CTAC and Ge AC transmission data obtained during free tidal breathing were used to correct PET emission images. Cold artifacts at the interface of the lungs and diaphragm, believed to be due to respiratory motion (RMA), that were seen on CTAC images but not on the Ge AC images were evaluated qualitatively on a four-point scale (0, no artifact; 1, mild artifact; 2, moderate artifact; 3, severe artifact). RMA was also measured for height. Curvilinear cold artifacts paralleling the dome of the diaphragm at the lung/diaphragm interface were noted on 84% of PET-CT image acquisitions and were not seen on the Ge-68-corrected images; however, these artifacts were infrequently severe. In conclusion, RMA of varying magnitude were noted in most of our patients as a curvilinear cold area at the lung/diaphragm interface, but were not diagnostically problematic in these patients.