Wang Enfeng, Wu Yin, Cheung Jerry S, Zhou Iris Yuwen, Igarashi Takahiro, Zhang XiaoAn, Sun Phillip Zhe
1 Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
2 Department of Radiology, Third Affiliated Hospital, Zhengzhou University, Zhengzhou, China.
J Cereb Blood Flow Metab. 2017 Oct;37(10):3325-3333. doi: 10.1177/0271678X17721431. Epub 2017 Jul 28.
Diffusion weighted imaging (DWI) has been commonly used in acute stroke examination, yet a portion of DWI lesion may be salvageable. Recently, it has been shown that diffusion kurtosis imaging (DKI) defines the most severely damaged DWI lesion that does not renormalize following early reperfusion. We postulated that the diffusion and kurtosis lesion mismatch experience heterogeneous hemodynamic and/or metabolic injury. We investigated tissue perfusion, pH, diffusion, kurtosis and relaxation from regions of the contralateral normal area, diffusion lesion, kurtosis lesion and their mismatch in an animal model of acute stroke. Our study revealed significant kurtosis and diffusion lesion volume mismatch (19.7 ± 10.7%, P < 0.01). Although there was no significant difference in perfusion and diffusion between the kurtosis lesion and kurtosis/diffusion lesion mismatch, we showed lower pH in the kurtosis lesion (pH = 6.64 ± 0.12) from that of the kurtosis/diffusion lesion mismatch (6.84 ± 0.11, P < 0.05). Moreover, pH in the kurtosis lesion and kurtosis/diffusion mismatch agreed well with literature values for regions of ischemic core and penumbra, respectively. Our work documented initial evidence that DKI may reveal the heterogeneous metabolic derangement within the commonly used DWI lesion.
扩散加权成像(DWI)已广泛应用于急性中风检查,但部分DWI病变可能是可挽救的。最近的研究表明,扩散峰度成像(DKI)可确定早期再灌注后未恢复正常的最严重受损的DWI病变。我们推测,扩散和峰度病变不匹配提示存在异质性血流动力学和/或代谢损伤。我们在急性中风动物模型中,研究了对侧正常区域、扩散病变区域、峰度病变区域及其不匹配区域的组织灌注、pH值、扩散、峰度和弛豫情况。我们的研究显示,峰度和扩散病变体积存在显著不匹配(19.7±10.7%,P<0.01)。虽然峰度病变与峰度/扩散病变不匹配区域之间的灌注和扩散无显著差异,但我们发现峰度病变区域的pH值(pH=6.64±0.12)低于峰度/扩散病变不匹配区域(6.84±0.11,P<0.05)。此外,峰度病变区域和峰度/扩散不匹配区域的pH值分别与缺血核心区和半暗带区域的文献值相符。我们的研究首次证明,DKI可能揭示常用DWI病变内的异质性代谢紊乱。