CT灌注成像联合血脑屏障损伤标志物对脓毒症相关性脑病的诊断价值

Diagnostic value of CT perfusion imaging combined with markers of blood-brain barrier injuryin of sepsis associated encephalopathy

目的探讨CT灌注成像联合血脑屏障损伤标志物对脓毒症相关性脑病(SAE)的诊断价值。方法选取2015年7月至2017年10月收治的脓毒症患者84例[男性46例、女性38例,年龄19~76(54.05±13.70)岁]。将发生SAE作为观察组(38例),不发生SAE作为对照组(46例),分别于入院后第1、3天检测血清闭锁蛋白(Occludin)、一氧化氮合酶(NOS)、神经元特异性烯醇化酶(NSE)、中枢神经特异蛋白(S100β)、胶质纤维酸性蛋白(GFAP)和兴奋性氨基酸(EAA)的水平,并行脑部CT灌注成像,计算感兴趣区(ROI)的脑血流量(rCBF)、血容量(rCBV)、平均通过时间(rMTT),比较两组患者血清学指标及CT灌注成像结果。组间、组内比较均行t检验,Logistic回归分析SAE发生与各指标的相关性。采用受试者工作特征(ROC)曲线分析各变量单独及联合检测诊断脓毒症脑病的临床价值。结果观察组患者第1、3天rCBF分别为(45.63±16.56)、(34.83±15.64)mL·100g^-1·min^-1,分别低于对照组的(63.61±16.61)、(56.34±15.74)mL·100g^-1·min^-1,且差异有统计学意义(t=4.945、8.003,均P=0.000);第1、3天rCBV分别为(2.04±0.95)、(1.59±0.86)mL/100g,分别低于对照组的(2.53±1.04)、(2.06±1.04)mL/100g,差异有统计学意义(t=2.234、2.240,均P=0.028);第3天rMTT为(3.92±0.93)s,高于对照组的(3.43±1.04)s,且差异有统计学意义(t=2.254,P=0.027)。入院后第3天,观察组患者血清Occludin、NOS、NSE、S100β、GFAP、EAA水平分别为(128.37±15.61)ng/L、(56.04±10.54)U/mL、(23.03±4.96)mg/L、(0.39±0.05)μg/L、(125.39±37.83)ng/L、(5.88±2.63)μmol/L,分别高于对照组的(115.21±12.56)ng/L、(51.67±11.30)U/mL、(20.43±3.34)mg/L、(0.35±0.06)μg/L、(82.67±16.55)ng/L、(4.73±1.05)μmol/L,且差异均有统计学意义(t=4.282、2.379、2.858、5.732、10.351、2.718,P=0.000、0.020、0.005、0.000、0.000、0.008)。Logistic回归分析发现,SAE的发生与入院后第3天的rCBF(95%CI:0.629~1.006,r=-0.624,P=0.037)、rCBV(95%CI:0.010~1.174,r=-0.709,P=0.040)呈负相关;与第3天的Occludin(95%CI:1.011~1.553,r=0.722,P=0.039)、GFAP(95%CI:1.005~1.154,r=0.688,P=0.035)水平呈正相关。ROC曲线分析结果发现,入院后第3天rCBF+rCBV+Occludin+GFAP联合检测时ROC曲线下面积最大,为0.939。结论脓毒症患者早期均表现出一定程度的神经元损伤,CT灌注成像联合血脑屏障损伤标志物检测对SAE具有较高的诊断价值。

Objective To explore the diagnostic value of CT perfusion imaging combined with markers of blood-brain barrier injury in sepsis-associated encephalopathy. Methods A total of 84 patients with sepsis were selected in the intensive medicine department from July 2015 to October 2017 and divided into observation and control groups according to the presence of sepsis-associated encephalopathy, there were 46 males and 38 females, aged 19-76(54.05±13.7). The serum levels of Occludin, nitric oxide synthase(NOS), neuron specific enolase(NSE), central nerve specific protein(S100β), glial fibrillary acidic protein(GFAP), and excitatory amino acids(EAA) were measured on the first and third day after admission. Brain CT perfusion imaging was performed to calculate regional cerebral blood flow(rCBF), relative cerebral blood volume(rCBV), and regional mean transit time(rMTT) in the region of interest(ROI). Serological and CT perfusion imaging parameters of the two groups were compared. T-test was performed for comparison between groups and within groups. The correlation between sepsis associated encephalopathy(SAE) and each indicator was analyzed by logistic regression analysis. The receiver operating characteristic(ROC) curve was used to analyze the clinical value of various variables in diagnosis of septic encephalopathy. Results The rCBF of patients in the observation group measured(45.63±16.56) and(34.83±15.64) mL·100 g^-1·min^-1 on the first and third day, respectively, which were lower than those of the control group at(63.61±16.61) and(56.34±15.74) mL·100 g^-1·min^-1. Statistically significant difference was observed(t=4.945, 8.003, both P=0.000). The rCBV on the first and third day reached(2.04±0.95) and(1.59±0.86) mL/100 g, respectively, which were lower than those of the control group(2.53±1.04) and (2.06±1.04) mL/100 g, presenting a statistically significant difference(t=2.234, 2.240, both P=0.028). The rMTT on the third day amounted to(3.92±0.93) s, which is higher than the(3.43±1.04) s of the control group, and the difference was statistically significant(t=2.254, P=0.027). Three days after admission, the levels of occludin, NOS, NSE, S100β, GFAP, and EAA of the observation group reached (128.37± 15.61) ng/L,(56.04±10.54) U/mL,(23.03±4.96) mg/L,(0.29±0.05)μg/L,(125.39±37.83) ng/L, and (5.88±2.63)μmol/L, respectively, which were higher than those of the control group, which yielded values of (115.21±12.56) ng/L,(51.67±11.30) U/mL,(20.43±3.34) mg/L,(0.35±0.06)μg/L,(82.67±16.55) ng/L, and (4.73±1.05)μmol/L. Significant differences were observed between the two groups(t=4.282, 2.379, 2.858, 5.732, 10.351, 2.718, P=0.000, 0.020, 0.005, 0.000, 0.000, 0.008). Logistic regression analysis showed that the incidence of sepsis-associated encephalopathy was negatively correlated with rCBF(95%CI: 0.629-1.006, r=-0.624, P=0.037) and rCBV(95%CI: 0.010-1.174, r=-0.709, P=0.040) and positively correlated with occludin(95%CI: 1.011-1.553, r=0.722, P=0.039) and GFAP(95%CI: 1.005-1.154, r=0.688, P=0.035) levels on the third day. ROC curve analysis revealed that the area under the curve, with combined detection of rCBF + rCBV + occludin + GFAP, reached 0.939 on the third day. Conclusion The patients with sepsis showed a certain degree of neuronal injury in the early stage, and the combined detection of CT perfusion imaging and markers of blood-brain barrier injury presented a high diagnostic value for sepsis-associated encephalopathy.