1Department of Neurosurgery, Graduate School of Biomedical and Health Science; and.
2Graduate School of Engineering, Hiroshima University, Hiroshima, Japan.
J Neurosurg. 2018 May;128(5):1280-1288. doi: 10.3171/2017.1.JNS162379. Epub 2017 Jul 7.
OBJECTIVE Carotid artery stenting (CAS) has been considered to prevent ischemic strokes caused by stenosis of the cervical carotid artery. The most common complication of CAS is new cerebral infarction. The authors have previously reported that the jellyfish sign-the rise and fall of the mobile component of the carotid plaque surface detected by carotid ultrasonography-suggests thinning and rupture of the fibrous cap over the unstable plaque content, such as the lipid-rich necrotic core or internal plaque hemorrhage. The authors' aim in the present study was to evaluate the risk of a new ischemic lesion after CAS by using many risk factors including calcification (size and location) and the jellyfish sign. METHODS Eighty-six lesions (77 patients) were treated with CAS. The presence of ischemic stroke was determined using diffusion-weighted imaging (DWI). Risk factors included calcification of the plaque (classified into 5 groups for size and 3 groups for location) and the jellyfish sign, among others. Multiple linear regression analysis (stepwise analysis and partial least squares [PLS] analysis) was conducted, followed by a machine learning analysis using an artificial neural network (ANN) based on the log-linearized gaussian mixture network (LLGMN). The additive effects of the jellyfish sign and calcification on ischemic stroke after CAS were examined using the Kruskal-Wallis test, followed by the Steel-Dwass test. RESULTS The stepwise analysis selected the jellyfish sign, proximal calcification (proximal Ca), low-density lipoprotein (LDL) cholesterol, and patient age for the prediction model to predict new DWI lesions. The PLS analysis revealed the same top 3 variables (jellyfish sign, proximal Ca, and LDL cholesterol) according to the variable importance in projection scores. The ANN was then used, showing that these 3 variables remained. The accuracy of the ANN improved; areas under the receiver operating characteristic curves of the stepwise analysis, the PLS analysis, and the ANN were 0.719, 0.727, and 0.768, respectively. The combination of the jellyfish sign and proximal Ca indicates a significantly increased risk for ischemic stroke after CAS. CONCLUSIONS The jellyfish sign, proximal Ca, and LDL cholesterol were considered to be important predictors for new DWI lesions after CAS. These 3 factors can be easily determined during a standard clinical visit. Thus, these 3 variables-especially the jellyfish sign and proximal Ca-may be useful for reducing the ischemic stroke risk in patients with stenosis of the cervical carotid artery.
颈动脉支架置入术（CAS）被认为可以预防颈内动脉狭窄引起的缺血性脑卒中。CAS 最常见的并发症是新发脑梗死。作者之前报道过，水母征——通过颈动脉超声检测到颈动脉斑块表面的移动成分的高低起伏——提示不稳定斑块（如富含脂质的坏死核心或内部斑块出血）上纤维帽变薄和破裂。本研究的目的是通过使用包括钙化（大小和位置）和水母征在内的许多危险因素来评估 CAS 后新发缺血性病变的风险。
86 个病灶（77 例患者）接受了 CAS 治疗。使用弥散加权成像（DWI）确定是否存在缺血性脑卒中。危险因素包括斑块钙化（按大小分为 5 组，按位置分为 3 组）和水母征等。进行了多元线性回归分析（逐步分析和偏最小二乘法[PLS]分析），然后使用基于对数线性高斯混合网络（LLGMN）的人工神经网络（ANN）进行机器学习分析。使用 Kruskal-Wallis 检验和 Steel-Dwass 检验来检验水母征和钙化对 CAS 后缺血性卒中的附加影响。
逐步分析选择水母征、近端钙化（近端 Ca）、低密度脂蛋白（LDL）胆固醇和患者年龄作为预测模型，以预测新的 DWI 病变。PLS 分析根据投影得分的变量重要性显示出相同的前 3 个变量（水母征、近端 Ca 和 LDL 胆固醇）。然后使用 ANN，结果显示这 3 个变量仍然存在。ANN 的准确性提高了；逐步分析、PLS 分析和 ANN 的受试者工作特征曲线下面积分别为 0.719、0.727 和 0.768。水母征和近端 Ca 的组合表明，CAS 后发生缺血性卒中的风险显著增加。
水母征、近端 Ca 和 LDL 胆固醇被认为是 CAS 后新发 DWI 病变的重要预测指标。这 3 个因素在标准临床就诊中很容易确定。因此，这 3 个变量——尤其是水母征和近端 Ca——可能有助于降低颈内动脉狭窄患者的缺血性卒中风险。
