Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
Invest Radiol. 2012 May;47(5):277-83. doi: 10.1097/RLI.0b013e31823fabc6.
To demonstrate the feasibility of using multidetector computed tomography with gadolinium contrast (Gd-MDCT) for the quantification of myocardial infarct (MI).
MI was induced in male swine (n = 6). One week later, the animals received 0.2-mmol/kg gadopentetate dimeglumine and were sacrificed. On the excised hearts, Gd-MDCT with several tube voltages (80, 120, and 140 kV), late gadolinium enhancement MRI (LGE-MRI), and triphenyl-tetrazolium-chloride staining were then conducted. We used a 2-SD threshold for the CT images and several threshold limits (2, 3, 4, 5, 6 SD, and full width at half-maximum [FWHM]) for the LGE-MRI images to delineate the infarct area. Total infarct volume and infarct fraction of each heart were calculated.
MI size measured by MDCT at 140 kV showed good correlation with the reference triphenyl-tetrazolium-chloride value. Applying an 80-kV tube voltage, however, significantly underestimated MI size. In our study, the LGE-MRI method, using the 6-SD threshold, provided the most accurate determination of MI size. LGE-MRI, using the 2- and 3-SD threshold limits, significantly overestimated infarct size.
The Gd-MDCT technique has been found suitable for the evaluation of MI in an ex vivo experimental setting. Gd-MDCT has the ability to detect MI even at low kV settings, but accuracy is limited by a high image noise because of reduced photon flux.
展示使用钆对比剂多排螺旋 CT（Gd-MDCT）对心肌梗死（MI）进行定量分析的可行性。
雄性猪（n=6）诱导 MI。一周后，这些动物接受 0.2mmol/kg 钆喷替酸葡甲胺，并进行安乐死。在取出的心脏上，进行 Gd-MDCT 检查（管电压分别为 80、120 和 140kV）、晚期钆增强 MRI（LGE-MRI）和三苯基四唑氯盐染色。我们使用 CT 图像的 2SD 阈值和 LGE-MRI 图像的多个阈值限制（2、3、4、5、6SD 和半最大值全宽[FWHM]）来描绘梗死面积。计算每只心脏的总梗死体积和梗死分数。
140kV 下 MDCT 测量的 MI 大小与三苯基四唑氯盐参考值具有良好的相关性。然而，使用 80kV 管电压会显著低估 MI 大小。在我们的研究中，使用 6SD 阈值的 LGE-MRI 方法提供了最准确的 MI 大小测定。使用 2SD 和 3SD 阈值限制的 LGE-MRI 显著高估了梗死面积。
Gd-MDCT 技术已被发现适用于在离体实验环境下评估 MI。Gd-MDCT 甚至在低千伏设置下也具有检测 MI 的能力，但由于光子通量减少导致图像噪声增加，准确性受到限制。
