Xie Xuewei, Jiang Qianmei, Suo Yue, Han Chong, Wang Zhaobin, Zhang Zhe, Wang Ning, Wang Yihuai, Zhang Chunguang, Xue Bingshan, Liu Tao, Wang David, Jing Jing, Wang Yongjun
Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Tiantan Neuroimaging Center of Excellence, China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Stroke Vasc Neurol. 2024 Nov 20. doi: 10.1136/svn-2024-003592.
The low-field MRI is a promising tool to accurately diagnose strokes. We here report our study on the accuracy of a 0.23-Tesla (0.23-T) MRI using the haematoma enhanced inversion recovery (HEIR) sequence to detect acute ischaemic stroke (AIS) and intracerebral haemorrhage (ICH) within 24 hours of symptom onset.
A novel HEIR sequence based on fluid-attenuated inversion recovery T1-weighted, with a scanning time of 1 min and 17 s, was developed using an ICH and AIS pig model on a 0.23-T MRI. Images of the pig model were obtained hourly for 24 hours in order to monitor value changes on T1/T2 and verify the differential diagnosis of AIS and ICH. Then, 30 patients with AIS and 30 patients with ICH with confirmed diagnoses by 3T-MRI/CT were included. Diagnostic criteria on a 0.23-T MRI for ICH was the hyperintensity signal on both the diffusion-weighted imaging (DWI) and HEIR sequence, while for AIS was the hyperintensity on DWI and isointensity on the HEIR sequence. Two blinded raters independently assessed the images obtained by the 0.23-T MRI for the presence of ICH/AIS.
In the pig model, setting the inversion time to 800 ms enabled clear differentiation of ICH from brain parenchymal tissue and AIS. In real patients, a correct 0.23-T MRI diagnosis of either an AIS or ICH was made in all 60 patients within 24 hours of symptom onset (100% overall accuracy). No adverse events occurred.
The 0.23-T MRI may have the potential to differentiate cerebral haemorrhage from cerebral infarction with both speed and accuracy, making brain MRI scans easier, faster and cheaper. It might be possible to improve the screening imaging process for strokes in the emergency room. Further multicentre studies are needed to validate our findings.
低场磁共振成像（MRI）是准确诊断中风的一种有前景的工具。我们在此报告一项关于使用血肿增强反转恢复（HEIR）序列的0.23特斯拉（0.23-T）MRI在症状发作24小时内检测急性缺血性中风（AIS）和脑出血（ICH）准确性的研究。
基于液体衰减反转恢复T1加权成像开发了一种新型HEIR序列，扫描时间为1分17秒，使用0.23-T MRI上的ICH和AIS猪模型。对猪模型每小时进行一次成像，持续24小时，以监测T1/T2值的变化并验证AIS和ICH的鉴别诊断。然后，纳入30例经3T-MRI/CT确诊的AIS患者和30例ICH患者。0.23-T MRI对ICH的诊断标准是扩散加权成像（DWI）和HEIR序列上均为高信号，而对AIS的诊断标准是DWI上为高信号且HEIR序列上为等信号。两名盲法评估者独立评估0.23-T MRI获得的图像中是否存在ICH/AIS。
在猪模型中，将反转时间设置为800毫秒可实现ICH与脑实质组织及AIS的清晰区分。在实际患者中，所有60例患者在症状发作24小时内均通过0.23-T MRI正确诊断出AIS或ICH（总体准确率100%）。未发生不良事件。
0.23-T MRI可能有潜力快速且准确地区分脑出血和脑梗死，使脑部MRI扫描更简便、快速且成本更低。有可能改善急诊室中风的筛查成像流程。需要进一步的多中心研究来验证我们的发现。
