脑血流断层显像Bullseye显示

为了探讨用Bullseye显示脑血流灌注显像数据的可能性,对8例典型脑梗塞病例及15例脑血流断层显像常规分析可疑病例的脑血流断层显像的横断面数据进行Bullscye显示,结果8例典型病人病灶用普通Bullseye即显示良好;常规分析可疑病例病变用普通Bullseye 8例显示良好,变黑Bullseye 13例显示出病灶;结果提示利用Bullseye显示脑血流灌注显像数据的可能。     

Simulating activations with cytoarchitecture

Cytoarchitectonic delineation of areas in post-mortem human brains provides the precise location of these areas. It has been possible to study the size and location of areas between post-mortem brains with multi-subject cytoarchitectonic data. If the structure–function relationship is assumed to be a one-to-one mapping for the purposes of inter-subject variability, then functional areas in the cortex will also adhere to the structure, and therefore, the location and size of cytoarchitectonic areas in the brain. Thus, it is possible to use the cytoarchitectonic data as being representative of the size and location of functional activations. Under this assumption, we simulated activations in cytoarchitectonic areas from ten post-mortem brains in this study. We then treated these data as we would a normal PET experiment. The purpose of this study is to demonstrate a standard PET image analysis on a simulated ten-subject PET study using cytoarchitecture to localize the activations. By doing so, we simulate activations with real inter-subject variability with the size and location of each area. Significant activations were obtained for activations simulated in areas 3a and 3b. A voxel-wise conjunction between simulated data and experimental data was made to better determine the underlying areas activated by the experimental tasks. This study presents a novel technique for demonstrating the effect of standard image analysis on the location and size of simulated activations as determined by cytoarchitectonic data from multiple subjects. Furthermore, this technique has been applied to better determine the underlying areas activated in an experiment.     

正中神经电刺激颅脑损伤后昏迷病人神经递质的变化

目的探讨正中神经电刺激对颅脑损伤后昏迷患者神经递质的变化及可能促苏醒作用机制。方法严重颅脑损伤昏迷患者40例,随机分为治疗组(n=20)和对照组(n=20)。对照组按常规治疗,治疗组在常规治疗的基础上加用正中神经电刺激治疗。每天给予正中神经电刺激30min,持续电刺激7天后,两组治疗相同。刺激一周后通过GCS评分评价两组的治疗效果。对比伤后3月时的GCS评分、神经功能恢复情况和语言功能情况,并同时采用放射免疫分析法检测刺激前和刺激结束后昏迷患者脑脊液中E、NE、DA、β-EP等神经递质的含量。结果治疗组患者持续刺激一周后,治疗组GCS评分平均提高(4.81±1.21)分,对照组GCS评分平均提高(1.99±0.64)分。两组比较有显著性差异(P<0.05)。伤后3个月时,治疗组患者GCS评分明显优于对照组(P<0.05),治疗组患者语言功能评分和生活质量评分也明显优于对照组。脑脊液中的β-EP下降速度较对照组快(P<0.05),治疗组脑脊液中DA、NE、E在神经电刺激前后变化与对照组相比无显著性差异(P>0.05)。结论正中神经电刺激治疗对颅脑外伤后昏迷患者确有促苏醒作用,减少致残率和提高患者生活质量。刺激后脑脊液中神经递质含量的变化可能是正中神经电刺激促苏醒的机制之一。     

丹参通脉胶囊对脑缺血再灌注损伤大鼠的作用

目的 观察丹参通脉胶囊对脑缺血再灌注大鼠的影响,探究其脑组织恢复程度。方法 取SD大鼠40只,制备脑缺血再灌注损伤模型（MCAO）,实验大鼠随机分为假手术组、模型组、血塞通组及丹参通脉胶囊组,观察脑缺血再灌注24 h后大鼠神经行为学评分、脑组织含水量、脑梗死体积、局部脑皮层血流量（rCBF）和局部微血管内皮细胞的变化情况。结果 与模型组及血塞通组比较,丹参通脉胶囊能显著降低大鼠的神经行为学评分（P<0.01）;降低脑组织含水量（P<0.01）;减小脑梗死体积（P<0.01）;提高局部脑组织血流量（P<0.01）;增加微血管内皮细胞的数量（P<0.01）。结论 丹参通脉胶囊对大鼠脑缺血再灌注损伤具有保护作用,可加速脑组织恢复。     

Penumbra around chronic cerebral infarction?

In a series of 13 patients with cerebrovascular occlusive disease regional cerebral blood flow (rCBF) measurements (two-dimensional intravenous ¹³³Xe clearance method) and quantitative EEG analysis (sensorimotor rhythms) as well as electronic measurement of handforce were performed before and during intravenous infusion of 1 μg kg/min of one of the lipophilic dihydropyridine calcium channel blocker nimodipine (Nimotop®). The aim of the study was to test the hypothesis of the existence of hypoperfusion (ischaemic penumbra) in the surroundings of chronic cerebral infarcts. All 3 parameters improved in one patient. Sensorimotor rhythms increased in 5 patients, rCBF in 3. EEG and rCBF improved in 2 patients. In 3 instances, a redistribution of rCBF in favour of the peri-infarct zone was noted (significant increase of rCBF from 35 ± 2 sem to 53 ± 4 ml/100 g/min (p > 0.01), whereas rCBF fell from 61 ± 5 to 46 ±2 ml/100 g/min on a collimator remote from the infarct but in the infarcted hemisphere. The parallel improvement of rCBF and EEG in brain regions surrounding chronic infarcts in 3 patients was interpreted as functional improvement as a consequence of nimodipine-induced normalization of peri-infarct hypoperfusion, i.e. reversal of flow-dependent neuronal silence and/or dysfunction.     

The prediction of rapid conversion to Alzheimer's disease in mild cognitive impairment using regional cerebral blood flow SPECT

Mild cognitive impairment (MCI) comprises a heterogeneous group with a variety of clinical outcomes and they are at risk for developing Alzheimer's disease (AD). The prediction of conversion from MCI to AD using the initial neuroimaging studies is an important research topic. We investigated the initial regional cerebral blood flow (rCBF) measurements using single photon emission computed tomography (SPECT) in individuals with 76 amnesic MCI (52 subjects converted to AD and 24 subjects did not convert to AD at 3-year follow-up) and 57 age- and gender-matched controls. We sought functional profiles associated with conversion to AD, then evaluated the predictive value of the initial rCBF SPECT. As compared with controls, AD converters demonstrated reduced blood flow in the bilateral parahippocampal gyri, precunei, posterior cingulate cortices, bilateral parietal association areas, and the right middle temporal gyrus. Non-converters also demonstrated significant reduction of rCBF in the posterior cingulated cortices and the right caudate nucleus when compared to controls. As compared with non-converters, converters showed reductions of rCBF in the bilateral temporo-parietal areas and the precunei. The logistic regression model revealed that reduced rCBF in the inferior parietal lobule, angular gyrus, and precunei has high predictive value and discriminative ability. Although a cross-validation study is needed to conclude the usefulness of rCBF SPECT for the prediction of AD conversion in individuals with MCI, our data suggest that the initial rCBF SPECT studies of individuals with MCI may be useful in predicting who will convert to AD in the near future.     

局部脑血流量检测在评估川芎嗪对脑功能干预的应用价值

目的评估川芎嗪对大鼠一侧大脑中动脉闭塞(MCAO）后两侧额叶、丘脑、小脑、下丘脑局部脑血流量(RegionalCerebralBloodFlow,rCBF)变化的干预作用。方法线栓法建立大鼠一侧MCAO模型,用氢清除法测定两侧额叶、丘脑、小脑、下丘脑MCAO后1、3、6、24hrCBF。结果一侧MCAO后,两侧额叶皮层、丘脑、下丘脑、对侧小脑rCBF下降,至24h恢复正常;川芎嗪干预组,两侧额叶、丘脑、下丘脑、对侧小脑rCBF较未用药组增加(P<0.05）。结论川芎嗪可减轻远隔部位脑功能障碍。     

海马额叶局部脑血流灌注异常对学习记忆功能的影响及生化机制

目的探讨海马、额叶rCBF灌注异常对学习记忆功能的影响及其发生的生化机制。方法将64只雄性健康成年SD大鼠随机分为手术组和假手术组。两组再分别被随机分为手术A、B、C、D组和假手术A0、B0、C0、D0组,各亚组大鼠分别于实验开始后4h8、h、24h、3d时依次采用"Y型电迷宫"、PeriFluxPF3型激光多谱勒血流仪和生化分析仪测定其学习记忆能力、额叶、海马的rCBF及其GABA、AchE的含量。比较各手术组和假手术组的学习记忆分值r、CBF量、额叶、海马区GABA、AchE的含量,并动态观察其不同时间的变化情况。结果手术组大鼠的学习指标EN、达标所需日数、TRT(s)分别为52.09±8.43、0.56±0.12、14.42±0.51,明显大于假手术组(29.46±5.31、0.34±0.05、12.23±0.39),而主动回避率(%)63.57±6.13,明显低于假手术组(84.32±4.87),两组差异均具有显著性(P<0.05)。手术组大鼠右侧额叶、海马区术后4h、8h、24h、3d时的rCBF明显低于假手术组相应脑区同一时点的rCBF(P<0.05)。手术组大鼠手术后不同时间额叶、海马区AchE、GABA含量则较对照组显著升高(P<0.05)。结论大鼠右侧额叶、右侧海马的rCBF的降低可能是导致其学习记忆能力障碍的重要危险因素;大鼠额叶、海马rCBF的降低所致该脑区GABA、AchE含量的变化,可能是大鼠学习记忆功能降低的生化基础。     

急性脑梗死患者早期脑血流变化研究

目的 探讨急性脑梗死早期患者的局部脑血流量变化。方法 对29例急性脑梗死患者在发病24h内同时行头部CT及SPECT检查，对30例健康志愿者进行头部CT及SPECT检查。结果 SPECT检出阳性率为10．34％（3／29）。表现为病灶区rCBF减低或缺损，其异常部位与临床表现相符。神经功能缺损越重，rCBF的灌注缺损就越低。结论 在患者尚未发生脑组织结构异常的代谢和功能性损伤时，SPECT可灵敏的探测到损伤局部的脑血流变化，对估计患者的预后。有一定的指导意义。