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PET是可以反映人体组织细胞血流、功能、代谢且可以进行分子成像研究的先进分子影像设备, 它的出现使核医学显像诊断进入了新的时代, 也使影像诊断真正进入了分子水平。然而, PET只能提供疾病的代谢和功能的变化, 在疾病的结构和病灶定位上尚有缺陷。近年来, PET-CT的出现在很大程度上解决了这个问题, 在多年的临床诊断中, 尤其对肿瘤的诊断、分期及疗效监测上, PET-CT发挥了重要作用[1]。现在, PET-CT已经成为临床实践和基础生物医学研究常用的检查方法, 技术日益成熟。但是, 由于CT提供的是相对有限的软组织对比度, 而且在显像过程中必要的辐射剂量可能会给患者或者实验动物带来一定的辐射损伤, 因此, 有必要应用其他清晰显示解剖结构的显像技术来弥补CT的不足。相对而言, MRI的软组织对比度清晰, 对人和动物没有辐射损伤, 成像序列丰富, 所以PET和MRI两种系统的融合一直是图像融合技术努力研究的前沿领域。
PET-MRI的临床研究进展
Clinical research of PET-MRI
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摘要: 多模式显像技术PET-CT和SPECT-CT已经成为临床实践和基础生物医学研究常用的检查方法,并且技术日益成熟。但PET-CT作为有效的临床基本检查工具,仍然受到许多限制,为克服这些困难,目前研究的热点集中在PET和MRI融合技术上。PET-MRI是综合了多参数功能成像和高分辨率的显像技术,尤其适用于对软组织要求较高、受照射剂量限制的小动物成像实验研究和人体临床研究,初步的研究结果显示,PET-MRI技术可在多方面优于PET-CT,PET和MRI在临床应用的互补作用将会使分子影像学进一步发展。
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关键词:
- 正电子发射断层显像术 /
- 磁共振成像 /
- 体层摄影术, X线计算机 /
- 图像处理, 计算机辅助
Abstract: Multimodality imaging with PET-CTand SPECT-CT has become commonplace in clinical practice and in preclinical and basic biomedical research.Although PET-CT is already an established clinical tool it still bears some limitations.To overcome these limitations, recent research concentrates on the combination of PET and MRI into one single machine.Combined PET-MRI allows for multi-parametric imaging and reveals one or more functional processes simultaneously along with high-resolution morphology.Especially in small-animal research, where high soft tissue contrast is required, andthescantimeaswellasradiation dose are critical factors, the combination of PET and MRI would be beneficial compared with PET-CT. -
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