[Combined application of multi-parameter semiquantitative Alberta stroke program early CT score to assess infarction severity in acute ischemic stroke]

Zhonghua Yi Xue Za Zhi. 2018 Jun 5;98(21):1697-1702. doi: 10.3760/cma.j.issn.0376-2491.2018.21.015.
[Article in Chinese]

Abstract

Objective: To explore the significance of multi-parameter semiquantitative Alberta Stroke Program Early CT Score (ASPECTS) in detecting core infarction in acute ischemic stroke (AIS) patients. Methods: Twenty-one consecutive AIS patients from Beijing Hospital were retrospectively reviewed in this study from August 2016 to August 2017. All the patients presented within 6 hours since symptom onset.All the patients underwent one-stop dynamic whole brain 4D CTA-CTP scan before treatments (intravenous thrombolysis, mechanical thrombectomy, or other endovascular recanalization). MRI scan was performed in all patients 3 to 7 days after initial administration. Multi-parameter ASPECTS was calculated on the affected hemisphere regarding noncontrast CT (NCCT) map, cerebral blood flow (CBF) map, cerebral blood volume (CBV) map, mean transit time (MTT) map and MRI-DWI map by subtracting 1 point from 10 for any abnormalities visually detected. The evaluative consistency and diagnostic efficiency were analyzed by Pearson's χ(2) test, kappa identity test, and Kendall's coefficient of concordance using IBM SPSS statistics 22.0 software. Results: Compared with DWI-ASPECTS or follow-up NCCT-ASPECTS, CBV-ASPECTS had the best performance on both the kappa identity test (kappa coefficient κ=0.74)and Kendall's coefficient of concordance (τ=0.70). All the values of sensitivity (77.8%), specificity (95.5%), positive likelihood ratio (17.27) and AUC(0.87)were the highest in CBV-ASPECTS, followed by dMTT-ASPECTS. Meanwhile, the misdiagnosis rate (4.5%), missed diagnosis rate (22.2%) and negative likelihood ratio were the lowest in CBV-ASPECTS, followed by dMTT-ASPECTS. dMTT-ASPECTS had the same specificity(95.5%) as CBV-ASPECTS did and it could reveal the infarction in the areas where CBV map showed normal. NCCT-ASPECTS had the lowest sensitivity (64.7%) and highest missed diagnosis rate (35.3%). The misdiagnosis rate of CBF-ASPECTS was the highest (25.2%) and AUC was the lowest (0.76). Conclusions: Multi-parameter semiquantitative ASPECTS may predict the infarction accurately in AIS patients. Compared with the single parameter of NCCT-ASPECTS, this new method may have better detectability and diagnostic performance.

目的: 通过对多参数半定量Alberta卒中项目早期CT评分(ASPECTS)在急性缺血性卒中的诊断效能的分析,探讨联合使用多参数ASPECTS评价急性缺血性卒中梗死核心区大小的价值。 方法: 回顾分析2016年8月至2017年8月经北京医院急性脑卒中绿色通道收治的发病6 h以内的21例前循环急性缺血性卒中(AIS)患者的影像资料。所有患者均于初诊治疗前行一站式全脑动态容积4D CTA-CTP检查,初诊后3~7 d行头颅MR检查或平扫CT(NCCT)复查,确定梗死核心。通过对治疗前、后的NCCT、CTP、MR图像进行ASPECT评分,利用χ(2)检验、kappa一致性分析、Kendall系数一致性评价等方法比较各参数图ASPECTS与DWI-ASPECTS或复查的NCCT-ASPECTS的一致性,并比较各参数的诊断效能。 结果: 与治疗后的DWI-ASPECTS或NCCT-ASPECTS相比,初诊脑血容量(CBV)-ASPECTS对AIS患者梗死核心评价的kappa一致性(kappa值κ=0.74)及Kendall系数一致性(一致性系数τ=0.70)均较好,且敏感度(77.8%)、特异度(95.5%)、阳性似然比(17.27)、AUC(0.87)均为最高,误诊率(4.5%)、漏诊率(22.2%)、阴性似然比(0.23)均为最低。平均通过时间缩短区ASPECTS(dMTT-ASPECTS)的特异度(95.5%)与CBV-ASPECTS一致,敏感度(75.8%)、阳性似然比(16.82)、AUC(0.86)均低于CBV-ASPECTS,但其能在CBV灌注图表现正常的患者中发现梗死病灶。NCCT-ASPECTS敏感度最低(64.7%),漏诊率最高(35.3%),CBF-ASPECTS误诊率最高(25.2%),AUC最低(0.76)。 结论: 多参数半定量ASPECTS联合使用能够准确预测AIS患者的梗死核心,相比于NCCT-ASPECTS的单参数评价方法,有着更好的诊断效能,在临床工作中有着很好的应用前景。.

Keywords: Perfusion imaging; Stroke; Tomography, X-ray computed.

MeSH terms

  • Alberta
  • Brain Ischemia
  • Cerebral Angiography
  • Cerebrovascular Circulation
  • Humans
  • Infarction
  • Retrospective Studies
  • Stroke*
  • Tomography, X-Ray Computed