Dey Damini, Slomka Piotr, Chien Daisy, Fieno David, Abidov Aiden, Saouaf Rola, Thomson Louise, Friedman John D, Berman Daniel S
Division of Nuclear Medicine, Department of Imaging, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA.
J Magn Reson Imaging. 2006 Mar;23(3):345-54. doi: 10.1002/jmri.20520.
To investigate direct volumetric in vivo correspondence of calcified atherosclerotic plaque lesions in MRI and CT images of the thoracic aorta by multimodality image registration and fusion.
Twelve CT (11 noncontrast and one contrast) and MRI (TruFISP, contrast T1-weighted volumetric interpolated breath-hold examination (VIBE)) data sets were co-registered by approximate segmentation of the aorta and subsequent automatic co-registration by maximization of mutual information (MI). We quantitatively assessed 22 co-registered calcified plaque lesions on CT and MRI.
The three-dimensional registration consistency and accuracy were 1.74 +/- 1.3 mm, and 2.42 +/- 1.65 mm, respectively. The ratio of CT/MRI calcified plaque volume decreased asymptotically with MRI volume, and correlated with average CT lesion density (r = 0.72) for small lesions (<25 mm(3)). The average calcified plaque volume, circumferential extent, and maximal radial width by MRI were significantly smaller compared to CT (35%, 68%, and 53%, respectively; P < 0.05).
Software co-registration allowed precise, direct, and voxel-based comparison of calcified atherosclerotic plaque lesions imaged by MRI and CT. In comparison with co-registered MRI, overestimation of calcified plaque in aortic CT due to "blooming" correlates with the average lesion density for small plaques, and is greater for small plaques.
通过多模态图像配准与融合，研究胸主动脉MRI和CT图像中钙化动脉粥样硬化斑块病变的直接活体容积对应关系。
12例CT（11例平扫和1例增强）和MRI（TrueFISP序列，增强T1加权容积内插屏气检查（VIBE））数据集，通过主动脉的近似分割和随后基于互信息最大化（MI）的自动配准进行共同配准。我们对CT和MRI上22个共同配准的钙化斑块病变进行了定量评估。
三维配准的一致性和准确性分别为1.74±1.3mm和2.42±1.65mm。CT/MRI钙化斑块体积比随MRI体积呈渐近性下降，对于小病变（<25mm³），与平均CT病变密度相关（r = 0.72）。与CT相比，MRI测得的钙化斑块平均体积、圆周范围和最大径向宽度明显更小（分别为35%、68%和53%；P < 0.05）。
软件配准允许对MRI和CT成像的钙化动脉粥样硬化斑块病变进行精确、直接且基于体素的比较。与共同配准的MRI相比，主动脉CT中由于“光晕”导致的钙化斑块高估与小斑块的平均病变密度相关，且小斑块更为明显。
