64排螺旋CT灌注成像在脑梗死早期诊断中的临床应用

探讨64排螺旋CT脑灌注成像（CTPI）对脑梗死超早期诊断的临床价值。对32例超早期脑梗死患者,均于发病6h内行CT平扫、CTPI检查,分析平扫及灌注成像表现,测量缺血区的脑灌注参数值。结果为32例患者中8例头颅CT平扫发现早期梗死征象,所有患者CTPI均发现脑灌注异常。脑梗死中心区脑血流量、脑血容量与对侧差异有极显著性意义（P〈0．01）;半暗带区脑血流量、达峰时间与对侧差异有极显著性意义（P〈0．01）,而脑血容量差异无显著性意义（P〉0．05）。CTPI能够在脑梗死发病的超早期发现病变,明确梗死灶存在及其范围、位置,预测半暗带区域,对脑梗死的早期诊断和治疗有重要价值,具有广泛临床应用前景。     

87例高血压脑出血术后护理体会

目的：总结高血压脑出血术后护理经验,探讨更为有效的护理方法．方法：对近两年收治的87例高血压脑出血术患者进行了回顾性分析．结果：生活自理33例,部分自理25例,植物生存3例,自动出院5例,其中并发肺炎致呼吸衰竭7例,急性肾功能衰竭4例,消化道出血3例,死亡7例．结论：采取有效的护理措施,可提高患者生存质量．     

氯吡格雷联合蚓激酶治疗急性期脑梗死的疗效观察

目的探讨氯吡格雷联合蚓激酶治疗急性期脑梗死的临床疗效。方法将143例脑梗死患者随机分为治疗组和对照组。比较两组治疗前后的血液流变学实验室指标、神经功能缺损程度评分及疗效。结果治疗组和对照组患者治疗前、后血液流变学各指标间差异均有显著性意义,且两组患者治疗后纤维蛋白原含量、红细胞聚集指数、红细胞变形指数、血浆粘滞度间差异均有显著性（P〈0．05）。治疗后7天起治疗组神经功能缺损程度评分较对照组明显减少,28d后差异更显著（P〈0．05）。治疗后28天疗效评定,治疗组总有效率为80．3％,对照组总有效率为69．4％,两组差异有显著性（P〈0．05）。结论氯吡格雷联合蚓激酶治疗急性期脑梗死疗效显著,且安全可靠,为急性期脑梗死的治疗提供了选择的机会。     

Direct measurement of oxygen extraction with fMRI using 6% CO2 inhalation

The blood-oxygenation-level-dependent (BOLD) signal is an indirect hemodynamic signal that is sensitive to cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral metabolic rate of oxygen. Therefore, the BOLD signal amplitude and dynamics cannot be interpreted unambiguously without additional physiological measurements, and thus, there remains a need for a functional magnetic resonance imaging (fMRI) signal, which is more closely related to the underlying neuronal activity. In this study, we measured CBF with continuous arterial spin labeling, CBV with an exogenous contrast agent and BOLD combined with intracortical electrophysiological recording in the primary visual cortex of the anesthetized monkey. During inhalation of 6% CO2, it was observed that CBF and CBV are not further increased by a visual stimulus, although baseline CBF for 6% CO2 is below the maximal value of CBF. In contrast, the electrophysiological response to the stimulation was found to be preserved during hypercapnia. As a consequence, the simultaneously measured BOLD signal responds negatively to a visual stimulation for 6% CO2 inhalation in the same voxels responding positively during normocapnia. These observations suggest that the fMRI response to a sensory stimulus for 6% CO2 inhalation occurs in the absence of a hemodynamic response, and it therefore directly reflects oxygen extraction into the tissue.     

Elevations of diffusion anisotropy are associated with hyper-acute stroke: a serial imaging study

Diffusion tensor imaging (DTI) studies of human ischemic stroke within 24 h of symptom onset have reported variable findings of changes in diffusion anisotropy. Serial DTI within 24 h may clarify these heterogeneous results. We characterized longitudinal changes of diffusion anisotropy by analyzing discrete ischemic white matter (WM) and gray matter (GM) regions during the hyperacute (2.5-7 h) and acute (21.5-29 h) scanning phases of ischemic stroke onset in 13 patients. Mean diffusivity (MD), fractional anisotropy (FA) and T2-weighted signal intensity were measured for deep and subcortical WM and deep and cortical GM areas in lesions outlined by a > or =30% decrease in MD. Average reductions of approximately 40% in relative (r) MD were observed in all four brain regions during both the hyperacute and acute phases post stroke. Overall, 9 of 13 patients within 7 h post symptom onset showed elevated FA in at least one of the four tissues, and within the same cohort, 11 of 13 patients showed reduced FA in at least one of the ischemic WM and GM regions at 21.5-29 h after stroke. The fractional anisotropy in the lesion relative to the contralateral side (rFA, mean+/-S.D.) was significantly elevated in some patients in the deep WM (1.10+/-0.11, n=4), subcortical WM (1.13+/-0.14, n=4), deep GM (1.07+/-0.06, n=1) and cortical GM (1.22+/-0.13, n=5) hyperacutely (< or =7 h); however, reductions of rFA at approximately 24 h post stroke were more consistent (rFA= 0.85+/-0.12).     

纳米磁性药物靶向动力学模拟

基于Navier-Stokes方程与Maxwell-Ampere理论建立了肿瘤细动脉中血液的非定常脉动模型,在磁场和流场耦合状态下研究引入纳米磁性药物后磁场对血液流场的影响.把离散模型和单相模型耦合,用有限元方法对纳米磁性药物在细动脉中的传输进行动力学模拟.模拟结果表明,磁场对纳米尺度磁性粒子的俘获形式明显不同于对微米尺度粒子,纳米磁性粒子运动轨迹与血液流线基本重合.由于磁性纳米粒子的存在,磁场影响了血液的流场分布,在磁体附近形成涡流区并长期滞留,以此方式实现对磁性药物的俘获.     

近红外空间分辨光谱技术及其对新生猪脑缺氧缺血的检测

近红外光谱(NIRS)技术作为一种无创的组织氧检测手段,近年来在脑缺氧缺血的检测方面日益受到重视。文章介绍了自行研制的NIRS仪器(TSAH-100近红外组织血氧无损监测仪)的基本原理及用于新生猪脑氧检测时如何实现传感器与待测脑组织的最佳耦合。检测了28例新生猪在不同氧合状态下的脑组织氧饱和度(regional cerebral oxygen saturation, rSO₂),在缺氧结束后进行了有创的动脉氧饱和度及生理参数的检测。结果表明,NIRS无创测得的脑rSO₂与血气分析有创测得的动脉血氧饱和度(SaO₂)有很好的相关性(p<0.001),并且脑rSO₂与缺氧程度及缺氧后生理参数的变化一致。因此NIRS无创测得的脑rSO₂能直接判断脑氧合状态,可在一定情况下替代有创血气分析,帮助临床无创、简便地诊断脑缺氧缺血。     

Resting state brain default network in patients with motor aphasia resulting from cerebral infarction

To explore the brain default mode network （DMN） in patients with motor aphasia resulting from cere- bral infarction, we used resting state functional magnetic resonance imaging （fMRI） to investigate the possible neural mechanism. Thirteen patients with motor aphasia resulting from cerebral infarction and ten matched controls were selected in this study. All subjects were examined using resting state fMRI. We chose the posterior cingulate cortex as the region of interest and then used functional connectivity analysis to calculate the DMN functional connectivity and analyze differences in the functional connectivity between the two groups. Compared with normal controls, aphasia patient group showed a significantly decreased functional connectivity in bilateral medial frontal gyrus, superior frontal gyrus, middle frontal gyrus, middle temporal gyrus, precuneus and cuneus. The aphasia patient group showed increased functional connectivity mainly in bilateral medial frontal gyrus, middle frontal gyrus, inferior frontal gyrus, precentral gyrus, insula. The DMN in cerebral infarction motor aphasia patients showed significantly decreased functional connectivity in the resting state. The DMN most likely plays an important role in motor aphasia resulting from cerebral infarction. Furthermore, functional connectivity inthe brain regions surrounding the left and right Broca＇s areas was significantly enhanced due to compensatory mecha- nisms. This may be helpful for the recovery of language function in cerebral infarction patients with motor aphasia.     

超声波治疗脑血管病的应用进展

本文介绍了应用超声波治疗脑血管病的应用情况，并对其临床意义进行评估。     

Three-vessel study of cerebral blood flow using phase-contrast magnetic resonance imaging: Effect of physical characteristics

The development of phase-contrast magnetic resonance imaging (P-C MRI) provides a noninvasive method for measurement of volumetric blood flow (VFR). We performed P-C MRI to study the effects of physical characteristics on cerebral blood flow. VFR of the left and right internal carotid arteries and basilar artery were measured using P-C MRI and total cerebral blood flow (tCBF) was calculated by summing up the VFR values in the three vessels. Moreover, we investigated the changes in these blood flows as influenced by age, head size, height, weight, body surface area, and handedness. The blood flows were 142 ± 58 ml/min (mean ± standard deviation) in the basilar artery; and 229 ± 86 ml/min in the left, and 223 ± 58 ml/min in the right internal carotid artery; and tCBF was 617 ± 128 ml/min. Significant increases were observed in head size-related change of VFR in the basilar artery (p = .028) and height-related change of tCBF (p = .045). The other characteristics did not significantly influence any VFR. The results suggest that head size and height may reflect CBF, and that these effects should be considered when changes of CBF are diagnosed. Phase-contrast MRI is useful for a noninvasive and rapid analysis of cerebral VFR and has potential for clinical use.