Ma H, Wright P, Allport L, Phan T G, Churilov L, Ly J, Zavala J A, Arakawa S, Campbell B, Davis S M, Donnan G A
National Stroke Research Institute, Florey Neuroscience Institutes, University of Melbourne, Melbourne, Vic, Australia.
Department of Medicine, Monash Medical Centre, Monash University, Melbourne, Vic, Australia.
Int J Stroke. 2015 Jun;10(4):565-70. doi: 10.1111/ijs.12203. Epub 2014 Mar 11.
In acute ischemic stroke perfusion/diffusion-weighted image, mismatch using magnetic resonance imaging approximates the ischemic penumbra. For early time windows, mismatch salvage improves clinical outcomes, but uncertainty exists at later time epochs. We hypothesized that (a) mismatch may exist up to 48 h; (b) the proportion of mismatch salvage is time independent; and (c) when salvaged, it improves clinical outcomes.
Magnetic resonance imaging was performed within 48 h of ischemic stroke. Perfusion-weighted image was defined by relative Tmax two-second delay. Perfusion/diffusion-weighted image mismatch was the perfusion-weighted image not overlapped by the diffusion-weighted image when coregistered. Infarct volume and disability (modified Rankin Score) were assessed at three-months. Mismatch salvage was the region not overlapped by final infarction. Favorable outcome was defined as modified Rankin Score 0-1.
Sixty-six patients were studied [mean age 69.9 years (standard deviation 13.1), initial median National Institute of Health Stroke Scale 9.0 (interquartile range 6.0, 18.3)]. There was no relationship between time of stroke onset and the proportion of mismatch salvaged (P = 0.73). Age (adjusted odds ratio = 0.92, 95% confidence interval 0.86-0.98, P = 0.01), initial National Institute of Health Stroke Scale (adjusted odds ratio = 0.80, 95% confidence interval 0.70-0.92, P < 0.01), mismatch volume (adjusted odds ratio = 0.98, 95% confidence interval 0.968-0.1, P = 0.05), and percentage of mismatch salvage (adjusted odds ratio = 1.04, 95% confidence interval 0.99-1.07, P = 0.05) were independently associated with favorable outcome.
Using coregistered perfusion/diffusion-weighted image criteria, mismatch persists up to 48 h post stroke. For the whole group, the proportion of mismatch salvage remains independent of time and, although the effect is small, its salvage is independently associated with improved clinical outcomes at three-months. Larger sample sizes are needed to determine the time limit for mismatch salvage.
在急性缺血性卒中灌注/扩散加权成像中，利用磁共振成像的不匹配现象可近似估算缺血半暗带。对于早期时间窗，不匹配区域的挽救可改善临床结局，但在较晚时间点仍存在不确定性。我们假设：（a）不匹配现象可能持续至48小时；（b）不匹配区域挽救的比例与时间无关；（c）当不匹配区域被挽救时，可改善临床结局。
在缺血性卒中发病48小时内进行磁共振成像检查。灌注加权成像通过相对Tmax延迟两秒来定义。灌注/扩散加权成像不匹配是指在配准后灌注加权成像未被扩散加权成像覆盖的区域。在三个月时评估梗死体积和残疾程度（改良Rankin量表评分）。不匹配区域的挽救是指未被最终梗死灶覆盖的区域。良好结局定义为改良Rankin量表评分0 - 1分。
共研究了66例患者[平均年龄69.9岁（标准差13.1），初始美国国立卫生研究院卒中量表中位数为9.0（四分位间距6.0，18.3）]。卒中发作时间与不匹配区域挽救的比例之间无相关性（P = 0.73）。年龄（调整后的比值比= 0.92，95%置信区间0.86 - 0.98，P = 0.01）、初始美国国立卫生研究院卒中量表评分（调整后的比值比= 0.80，95%置信区间0.70 - 0.92，P < 0.01）、不匹配体积（调整后的比值比= 0.98，95%置信区间0.968 - 0.1，P = 0.05）以及不匹配区域挽救的百分比（调整后的比值比= 1.04，95%置信区间0.99 - 1.07，P = 0.05）均与良好结局独立相关。
采用配准后的灌注/扩散加权成像标准，卒中后48小时内不匹配现象持续存在。对于整个研究组，不匹配区域挽救的比例与时间无关，尽管其影响较小，但不匹配区域的挽救与三个月时临床结局的改善独立相关。需要更大样本量来确定不匹配区域挽救的时间界限。
