Saccular Aneurysm of the Azygos Anterior Cerebral Artery: Three Case Reports

The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature.     

Cerebral Cortical Aquaporin-4 Expression in Brain Edema following Cardiac Arrest in Rats

OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.     

急性脑梗死诱发全身炎症反应综合征致多器官功能障碍综合征的临床研究

目的　探讨急性脑梗死 (ACI)诱发全身炎症反应综合征 (SIRS)致多器官功能障碍综合征(MODS)的发病机制 ,以及血清肿瘤坏死因子 (TNF α)、白细胞介素 (IL 1) β含量变化在ACI诱发SIRS发生、发展并向MODS转化的临床意义。方法　 6 8例ACI患者根据病情变化分为 3组 ,其中单纯性ACI(SACI组 ) 36例 ,ACI致SIRS(SIRS组 ) 32例 ,ACI致SIRS后发展为MODS(MODS组 ) 2 4例 ;应用酶联免疫吸附法 (ELISA法 )分别测定患者不同病程中血清TNF α、IL 1β值 ,并与对照组 (为 2 8名同期健康体检者 )比较。 结果　 (1) 6 8例ACI中 4 7.0 6 %发生SIRS;SIRS时 75 %发生MODS。 (2 )血清TNF α、IL 1β的含量MODS 组 >SIRS组 >SACI组 >对照组 ,各组间比较 ,差异具有极显著性 (均P <0 0 1)。MODS重症者 (积分≥ 9分 )血清TNF α、IL 1β含量高于轻症者 (积分 <9分 ) (均P <0 0 1) ;MODS死亡者血清TNF α、IL 1β含量高于存活者 (均 P <0 0 1)。结论　 (1)ACI后出现SIRS可导致MODS的发生。 (2 )患者血清TNF α、IL 1β水平异常变化可作为判断ACI致SIRS、MODS病情进展、预后及转归的一项指标     

艾司洛尔控制开颅手术苏醒期脑过度灌注的效果

目的 通过监测脑血流速度、颈静脉球部血氧饱和度(SjvO2)、血压、心率(HR)和不良反应发生率等,综合评价艾司洛尔用于控制开颅手术苏醒期患者脑过度灌注的效果.方法 选择择期在全身麻醉下行开颅肿瘤切除术的患者,随机分为艾司洛尔组(E组,20例)和对照组(C组,20例).E组患者从拔管即刻起给予艾司洛尔0.6 mg·kg1·h-1静脉持续滴注15 min C组患者从拔管即刻起给予0.9%氯化钠溶液静脉持续滴注.分别监测两组患者术前、术后拔管即刻及拔管后15、30、45、60 min时的大脑中动脉平均血流速度(MCAVm)、SivO2平均动脉压(MAP)及HR,并记录不良反应发生例数.结果 E组术后15和30 min的MCA Vm、sjvO2及HR均显著低于C组(P值均<0.01),术后15 Min的MAP显著低于C组(P<0.05).无一例患者发生与艾司洛尔相关的药物不良反应.结论 艾司洛尔是控制术后脑过度灌注的理想药物.     

中风后癫痫的临床研究

本文报告３６例中风后癫痫发作的临床和ＣＴ资料。通过回顾性病历复习和随访发现，中风后癫痫的发生率占同期住院中风患者的５．２６％，以蛛网膜下腔出血和脑栓塞发生癫痫比率最高，分别为１５％和１２．５％。癫痫发作与ＣＴ所见病灶分布密切相关，皮质病灶较皮质下病灶更易发生病病。癫痫发作可发生于中风后任何时期，但早期癫痫以出血性中风多见，而迟发性癫痫则更多见于脑梗塞患者。     

Transcranial cerebral oximetry and carotid cavernous fistula occlusion

Summary Different methods have been used in the evaluation and monitoring of the cerebral oxygen supply during neuro-interventional therapies. Attenuation of near-infrared light by the chromophores oxyhemoglobin and deoxyhemoglobin have shown to be useful in the study of the cellular oxygen metabolism and oxygen delivery to the brain. Transcranial cerebral oximetry (TCCO) has the advantage of providing real-time information regarding regional brain oxygen saturation (rSO₂) by using wavelengths in the near-infrared range.We present a patient with a carotid cavernous fistula who underwent balloon occulusion and concurrent continuous TCCO monitoring. TCCO was found to be a useful tool providing immediate rSO₂ values during the angiographic and interventional procedures. Initial balloon occlusion of a carotid cavernous fistula resulted in partial occlusion of the internal carotid artery lumen causing an immediate decrease in rSO₂ which correlated with angiographic findings. Subsequent reocclusion of the fistula produced a slower and smaller degree of decrease in rSO₂ with clinical improvement in the patient. Changes in rSO₂ were detected before any adverse clinical event was observed. TCCO was reliable, safe, sensitive, and provided a real-time assessment tool for the monitoring of brain oxygen supply in a patient undergoing a neuroendovascular procedure.     

Reversible reorganisation of the motor cortical representation of the hand in cervical dystonia.

Previous work has suggested that there may be a widespread disturbance of motor control mechanisms in patients with cervical dystonia. In the present study, we used transcranial magnetic stimulation to investigate the topography of the corticomotor projection to the abductor pollicis brevis (APB) muscle in 10 subjects with idiopathic torticollis. Threshold-adjusted stimuli were delivered at multiple scalp sites during a low-level voluntary contraction of the APB, and maps were generated of motor evoked potential amplitude versus scalp site. The cortical maps for the APB on the side opposite to the direction of head rotation were displaced laterally or posteriorly in all subjects and reverted to a more normal position after botulinum toxin injection of the cervical muscles in 5 subjects. The findings point to a reversible reorganisation of the corticomotor representation of the hand on the same side as the sternocleidomastoid (SCM) muscle that is involved in producing the dystonia. These results provide further evidence for the involvement of cortical centres and for a more widespread abnormality of motor control mechanisms in focal dystonia. The findings also support the notion that head turning is chiefly mediated by the hemisphere ipsilateral to the direction of the head rotation by means of a corticomotor projection to the contralateral SCM.     

Local variations in the cerebral microcirculatory response to hypercapnia and haemorrhage

Summary This study evaluates local variations of the cerebral vasomotor responses to hypercapnia and haemorrhagic hypotension in a pig model. Four laser Doppler flow probes were used in each pig. There was considerable variation in laser Doppler signals between the four probes in baseline recordings. The increases in flow after CO₂ administration in 7 pigs had a mean coefficient of variation of 0.43 ± 0.31, and the flow changes after blood loss in another 7 pigs had a mean coefficient of variation of 0.45 ± 0.34. The range of flow changes within each animal was large; the probe with the highest CO₂ response showed on the average a 273% ± 157% larger CO₂ response than the probe with the lowest CO₂ response. Correspondingly, the probe with the best preserved blood flow after blood loss had on the average a flow value of 93% ± 12% of the baseline value, while the probe that changed most with haemorrhage had a flow value of 44% ± 24% of the baseline value. Single laser Doppler recordings have been used for the monitoring of cerebral blood flow in neurosurgical critical care, but our results suggest that a single laser Doppler flow probe is not an adequate method to monitor vasoreactivity in neurosurgical patients because flow signals from one probe may be unrepresentative for other sites in the brain.     

硫酸镁联合亚低温治疗对大鼠局灶性脑缺血的保护作用

目的　探讨硫酸镁对SD大鼠局灶性脑缺血损伤的保护作用。方法　将 4 0只大鼠随机分成模型对照组、硫酸镁治疗组、亚低温治疗组、硫酸镁联合亚低温治疗组。采用线栓法建立大鼠局灶性脑缺血模型。通过计算大鼠神经功能缺陷评分 ,测量脑梗死体积 ,观察神经元超微结构改变 ,评定硫酸镁联合亚低温治疗作用。结果各治疗组大鼠神经功能评分及脑梗死体积均显著低于对照组 (P <0 0 5 ) ,联合治疗组大鼠明显低于对照组 (P<0 0 1) ;联合治疗组神经元超微结构改变轻微。结论　硫酸镁联合亚低温治疗对大鼠局灶脑缺血有明显保护作用