Sakamoto Yuki, Okubo Seiji, Nito Chikako, Suda Satoshi, Matsumoto Noriko, Abe Arata, Aoki Junya, Shimoyama Takashi, Muraga Kanako, Kanamaru Takuya, Suzuki Kentaro, Go Yuki, Mishina Masahiro, Kimura Kazumi
Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
Cerebrovasc Dis. 2017;44(3-4):203-209. doi: 10.1159/000479593. Epub 2017 Aug 16.
Thrombus visualization in patients with acute ischemic stroke has been detected and reported using various imaging modalities. T1-weighted imaging (T1-WI) can depict thrombi as hyperintense signals within vessels. Moreover, in addition to thrombi, T1-WI hyperintensities in arteries may suggest arterial dissection. However, the frequency of and factors related to the T1-hyperintense vessel sign (T1-HVS) are not fully known. The aim of this study was to clarify the prevalence of and related factors for the T1-HVS in patients with acute ischemic stroke.
From September 2014 through December 2015, consecutive acute ischemic stroke patients who were admitted to our stroke unit within 7 days from symptom onset were retrospectively recruited from the prospective registry. A T1-HVS was defined as the presence of a hyperintense signal, with intensity higher than surrounding brain, within the vessel lumen. Moreover, T1-HVSs were separated into filled T1-HVSs (hyperintensity fills whole vessel lumen) and non-filled T1-HVSs. The frequency of the T1-HVS and the timing of emersion and the relationship between the presence of the T1-HVS and arterial occlusion were assessed.
A total of 399 patients (139 women; median age 73 years; National Institutes of Health Stroke Scale score 3) were enrolled in the present study. Of these, 327 (82%) patients had T1-WI on admission. Two hundred and sixty-seven (67%) subjects had at least one follow-up T1-WI (median 6 days after admission), and 134 (34%) cases had ≥2 follow-up T1-WI examinations. The T1-HVS was observed in 18 patients during admission; therefore, the frequency of the T1-HVS in acute ischemic stroke patients was 4.5% (95% CI 2.5-6.5%). All but one (94%) of the T1-HVSs were first observed on follow-up imaging, and the median number of days from onset to T1-HVS appearance was 9. For patients having initial major artery occlusion and follow-up MRI (n = 95), sensitivity and specificity of the T1-HVS for persistent arterial occlusion on follow-up MR angiography were 22 and 100%, respectively. T1-HVS persisted for a few months and then normalized. Although there were no significant differences between filled and non-filled T1-HVS, more patients with non-filled T1-HVS had arterial dissection (43%) than those with filled T1-HVS (9%, p = 0.245).
The T1-HVS was observed in 4.5% of acute ischemic stroke patients. T1-HVSs appeared in the subacute phase in arteries with persistent occlusion and remained for a few months.
急性缺血性卒中患者的血栓可视化已通过多种成像方式得以检测和报道。T1加权成像（T1-WI）可将血栓描绘为血管内的高信号。此外，除血栓外，动脉T1-WI高信号可能提示动脉夹层。然而，T1高信号血管征（T1-HVS）的发生频率及相关因素尚不完全清楚。本研究旨在明确急性缺血性卒中患者中T1-HVS的患病率及相关因素。
从2014年9月至2015年12月，对症状发作后7天内入住我们卒中单元的连续急性缺血性卒中患者进行回顾性招募，这些患者来自前瞻性登记处。T1-HVS定义为血管腔内存在强度高于周围脑组织的高信号。此外，T1-HVS分为充盈性T1-HVS（高信号充满整个血管腔）和非充盈性T1-HVS。评估T1-HVS的发生频率、出现时间以及T1-HVS的存在与动脉闭塞之间的关系。
本研究共纳入399例患者（139例女性；中位年龄73岁；美国国立卫生研究院卒中量表评分3分）。其中，327例（82%）患者入院时进行了T1-WI检查。267例（67%）受试者至少进行了一次随访T1-WI检查（入院后中位6天），134例（34%）病例进行了≥2次随访T1-WI检查。18例患者在入院期间观察到T1-HVS；因此，急性缺血性卒中患者中T1-HVS的发生率为4.5%（95%CI 2.5-6.5%）。除1例（94%）外，所有T1-HVS均在随访成像时首次观察到，从发病到T1-HVS出现的中位天数为9天。对于有初始大动脉闭塞并进行随访MRI的患者（n = 95），T1-HVS对随访磁共振血管造影上持续性动脉闭塞的敏感性和特异性分别为22%和100%。T1-HVS持续数月后恢复正常。虽然充盈性和非充盈性T1-HVS之间无显著差异，但非充盈性T1-HVS患者发生动脉夹层的比例（43%）高于充盈性T1-HVS患者（9%，p = 0.245）。
4.5%的急性缺血性卒中患者观察到T1-HVS。T1-HVS出现在持续性闭塞动脉的亚急性期，并持续数月。
