PET／MR一体机操作优化的初步经验

目的通过比较PET／CT和PET／MR，初步探索PET／MR一体机的操作流程和成像优化方案。方法228例患者同日内接受PET／CT和PET／MR检查，通过6种不同MR序列与PET采集组合方案，比较图像质量的优劣，以在保证诊断信息基础上缩短患者扫描时间的原则分析判断，并初步确定最优PET／MR一体机采集方案。结果PET／MR结果与PET／CT相近，但其操作流程和注意事项有独特之处；在6种方案中，以躯干和头部各有独立序列组合、兼顾各向同性结构显示与突出病灶特点的方案6效果最优；PET／MR比PET／CT更易产生伪影。结论在优化方案基础上，PET／MR可获得与PET／CT一致的诊断级图像，但PET／MR采集时间长、伪影多，有待进一步完善。

Initial experience on protocol optimization for integrated PET/MR

Objective To investigate the optimal workflow and protocol for integrated PET/MR by comparison with PET/CT. Methods A total of 228 patients were enrolled in this study for PET/CT and PET/MR evaluation on the same day. Six PET/MR protocols with different MR sequences but the same PET acquisition protocol were investigated and the optimal protocol was identified based on image quality, acqui- sition time and diagnostic performance. Results PET/MR workflow was similar to PET/CT, however, some special issues needed to be considered for PET/MR. Among the 6 protocols, protocol No.6 outper- formed others for body and head regions. Types of artifacts were found more often in PET/MR than in PET/ CT. Conclusions By optimizing the protocol, PET/MR could achieve almost the same diagnostic performance as PET/CT. However, the issues of long acquisition time and artifacts on PET/MR need to be further improved.