Department of Biomedical Engineering, Kyung Hee University, Yongin, Korea.
J Magn Reson Imaging. 2013 Jul;38(1):189-97. doi: 10.1002/jmri.23960. Epub 2012 Dec 12.
To show the feasibility of magnetic resonance electrical impedance tomography (MREIT) conductivity imaging in terms of its capability to provide new contrast information of abscess lesion and characterize time-course variations before and after the induction of brain abscess.
Brain abscess was induced in healthy beagles by a direct inoculation method using Staphylococcus pseudintermedius. After the induction, four electrodes were attached on the head and the dog was placed inside the magnetic resonance imaging (MRI) bore. Using a current source, we injected a current of amplitude 5 mA and a pulse width of 81 msec. A multi-echo ICNE pulse sequence was used to obtain the magnetic flux density (Bz ) data.
The relative conductivity contrast ratios (rCCR, %) of abscess lesion were significantly changed by the postinduction time (P < 0.01). The rCCRs of central abscess lesions were higher than the surrounding area at 6, 12, and 18 hours (P < 0.01). Over 12 hours, the relationship between the induction time and rCCR showed a positive correlation followed by a negative correlation (P < 0.01).
We performed in vivo disease model animal experiments to validate the MREIT technique providing conductivity information of tissues in situ to be utilized in clinical applications.
展示磁共振电阻抗断层成像（MREIT）在提供脓肿病变新的对比信息和对脓肿形成前后的时间变化进行特征描述方面的可行性。
采用金黄色葡萄球菌（Staphylococcus pseudintermedius）直接接种法在健康比格犬体内诱导脑脓肿。诱导后，将四个电极贴在头部，将狗放在磁共振成像（MRI）孔内。使用电流源，我们注入幅度为 5 mA、脉冲宽度为 81 msec 的电流。使用多回波 ICNE 脉冲序列获取磁场密度（Bz）数据。
脓肿病变的相对电导率对比比（rCCR，%）随诱导后时间显著变化（P < 0.01）。在 6、12 和 18 小时时，中央脓肿病变的 rCCR 高于周围区域（P < 0.01）。在 12 小时以上，诱导时间与 rCCR 之间的关系呈正相关，随后呈负相关（P < 0.01）。
我们进行了体内疾病模型动物实验，以验证 MREIT 技术能够提供组织原位的电导率信息，用于临床应用。
