Gandhi Jenny M, Cherian P Mathew, Mehta Pankaj, Vardhraj Shriram, Santosh P, Elango S
Department of Neuro and Intervention Radiology, Kovai Medical Centre and Hospital, Avinashi Road, Coimbatore, Tamil Nadu, India.
Neurol India. 2022 May-Jun;70(3):1041-1047. doi: 10.4103/0028-3886.349638.
BACKGROUND/PURPOSE: Following endovascular intervention for stroke, hyperattenuated areas are common in brain parenchyma and it is difficult to differentiate on non-contrast CT whether it is contrast staining or reperfusion hemorrhage. Differentiation between contrast staining from reperfusion hemorrhage is of paramount importance for early initiation of antiplatelets and/or anticoagulants to prevent reocclusion of vessel. This study demonstrates signal characteristics of contrast-staining and reperfusion hemorrhage on susceptibility weighted MRI and its role to differentiate between two.
MATERIALS/METHODS: Between July 2017 to March 2019, 36 patients who presented with acute ischemic stroke due to large vessel occlusion underwent mechanical thrombectomy. Low-osmolar non-ionic (Iopromide 300 mg/L) iodinated contrast was used in all patients who underwent endovascular intervention. All patients underwent noncontrast CT brain and SWI on 3T MRI within 30 minutes of endovascular intervention. MRI was evaluated by two neuroradiologists. Reperfusion hemorrhage was defined as ECASS criteria II. Symptomatic ICH was defined as hemorrhagic transformation temporally related to a negative shift in NIHSS score >/=4.
Out of 36 patients, 15 had hyperattenuated areas in brain on NCCT. Out of 15, 13 patients had blooming on SWI, suggestive of bleed. Two patients had no blooming on SWI, suggestive of contrast staining. Two patients didnot show any hyperdensity on NCCT but blooming on SWI, suggestive of bleed.
All patients with hyperdensity on NCCT secondary to bleed showed blooming on SWI whereas those with contrast staining didnot show any signal changes on SWI. Thus, it is possible to differentiate reperfusion hemorrhage from contrast staining using SWI MRI. The significance of SWI in normal CT may be low where a small bleed maynot have any clinical significance.
背景/目的：在对中风进行血管内介入治疗后，脑实质内出现高密度区域很常见，在非增强CT上很难区分是造影剂染色还是再灌注出血。区分造影剂染色和再灌注出血对于早期启动抗血小板药物和/或抗凝剂以预防血管再闭塞至关重要。本研究展示了磁敏感加权MRI上造影剂染色和再灌注出血的信号特征及其在两者鉴别中的作用。
材料/方法：2017年7月至2019年3月期间，36例因大血管闭塞导致急性缺血性中风的患者接受了机械取栓术。所有接受血管内介入治疗的患者均使用了低渗非离子型（碘普罗胺300mg/L）碘化造影剂。所有患者在血管内介入治疗后30分钟内接受了脑部非增强CT和3T MRI的磁敏感加权成像（SWI）。MRI由两名神经放射科医生进行评估。再灌注出血按照欧洲急性卒中协作研究（ECASS）标准II定义。有症状的颅内出血定义为与美国国立卫生研究院卒中量表（NIHSS）评分负向变化≥4相关的出血性转化。
36例患者中，15例在非增强CT上脑内有高密度区域。在这15例中，13例患者在SWI上有磁敏感信号增强，提示出血。2例患者在SWI上没有磁敏感信号增强，提示造影剂染色。2例患者在非增强CT上未显示任何高密度影，但在SWI上有磁敏感信号增强，提示出血。
所有因出血导致非增强CT上出现高密度影的患者在SWI上均有磁敏感信号增强，而造影剂染色的患者在SWI上未显示任何信号变化。因此，使用SWI MRI可以区分再灌注出血和造影剂染色。在正常CT情况下，SWI的意义可能较低，因为小出血可能没有任何临床意义。
