脊椎转移瘤增强减影MR成像

目的评估增强减影在脊椎转移瘤MR I中的应用价值。方法50例脊椎转移瘤病人进行MR I增强扫描,对比剂采用Gd-DTPA(0.1 mmol/kg),然后用T1W I增强后的图像与增强前的图像进行减影。通过对比噪声比(CNR)、信噪比(SNR)以及肿瘤边界清晰程度的比较,对MR I减影与否进行评估。结果MR I对比增强减影图像比传统的T1W I增强图像显示更清晰、更直观。所有脊椎转移瘤图像MR I减影的CNR和SNR比常规T1W I增强图像的CNR和SNR高。MR I减影CNR为155.05±24.73(x±SD),常规T1W I增强图像的CNR为11.11±14.26(t=35.65,Ρ<0.001)。MR I减影SNR为192.82±32.89(x±SD),常规T1W I增强图像的SNR为46.03±28.22(t=23.95,Ρ<0.001))。MR I对比增强减影图像比传统的T1W I增强图像能更好地显示脊椎转移瘤的边界和侵犯情况(2χ=29.34,Ρ<0.005)。结论MR I增强减影为探查和评估脊椎转移瘤提供了一个新的诊断方法。     

高压氧治疗急性一氧化碳中毒174例护理效果观察

急性CO中毒是我国北方地区冬季的常见病,多发病。若治疗不及时或不彻底又有发生CO中毒迟发性脑病的危险。自从高压氧医学产生和发展以来,目前已成为CO中毒首选的主要治疗手段,取得了很好的治疗效果。本文对近3年来用高压氧(HBO)配合临床药物治疗CO中毒及迟发性脑病174例的治疗护理效果进行了观察,认为对急性CO中毒患者的治疗护理应及早发现、及早就医、及早HBO治疗并坚持足够的疗程,可以提高CO中毒的治愈率,降低死亡率,减少或减轻迟发性脑病的发生,同时认为整个HBO治疗过程中做好每个环节的护理工作是CO中毒患者救治成功的关键。1…     

多体素MRS在星形细胞瘤中的应用价值

目的探讨多体素MRS在不同级别星形细胞瘤术前诊断的应用价值。方法搜集22例病理证实的脑星形细胞瘤,分为高、低级别2组,行MR常规、增强扫描及MRS检查,比较Cho/Cr、NAA/Cr、Cho/NAA比值及Lac、Lip情况。结果高级别组表现为Cho明显增高,NAA及Cr明显降低,低级别组表现为Cho轻到中度不等增高和NAA不同程度的降低,高、低级别组间Cho/Cr、NAA/Cr以及Cho/NAA比值差别有意义。肿瘤周边水肿区与对侧正常脑组织间Cho/Cr、Cho/NAA比值差别有意义,NAA/Cr比值差别无统计学意义。高级别组中有11例出现Lac峰,7例出现Lip峰,低级别组中仅有2例出现Lac峰,无Lip峰出现。结论多体素H-MRS在术前全面评价星形细胞瘤不同级别间的鉴别诊断及确定肿瘤边界形态方面有重要的临床意义。     

磁共振质子波谱成像(1H-MRSI) 在胶质瘤诊断中的应用

目的探讨利用磁共振波谱成像(MRSI)反映胶质瘤恶性度的价值.方法41例病理证实胶质瘤,原发39例、复发2例,行MR及MRS扫描,MRS数据经残差Z分数统计模型及LLI、Lip/Cho等指标划分肿瘤边界及不同代谢区,并结合MRI结构成像,划分出肿瘤的高代谢活性区、肿瘤浸润边界、坏死区及乏氧区.结果肿瘤浸润边界均超过MR常规图像上的肿瘤边界.Ⅱ级肿瘤高代谢活性区大部分位于肿瘤区内,但Ⅲ、Ⅳ级则大部分位于肿瘤边界;随肿瘤恶性度升高,肿瘤出现了坏死区及乏氧区.结论MRSI对确定肿瘤恶性度及划分肿瘤边界具有一定价值.     

亚低温治疗重型颅脑损伤中脑组织氧分压的临床意义

目的观察亚低温治疗重型颅脑损伤过程中患者颅内压及脑组织氧分压的变化及临床意义。方法将80例急性重型颅脑损伤患者,随机分为亚低温治疗组(40例)和对照组(40例)。亚低温组入院后或术后立即给予亚低温治疗,保持肛温在32~34℃,持续24h~5d;对照组给予常规治疗。两组均观察颅内压(ICP)和脑组织氧分压(PbtO2)变化。结果亚低温组治疗后,ICP明显下降,PbtO2逐渐升高,与对照组相比有显著性差异。结论亚低温治疗能降低脑外伤后增高的ICP,提高PbtO2;伤后24h内持续PbtO2<5mmHg预示患者预后不良。     

Cerebral autoregulation is preserved in multiple system atrophy: A transcranial Doppler study.

Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.     

移植人羊膜细胞对大鼠创伤性脑损伤的实验研究

目的 探究大鼠TBI后脑内移植人羊膜细胞（HACs）对大鼠运动功能的影响。方法 HACs经分离、Hoechst33342标记后重悬调整细胞浓度为10^5/μl；采用改进的Feeney自由落体法打击大鼠脑皮层后肢运动区域，损伤后24h经微量注射器和立体定向仪将Hoechst33342标记的HACs 10μl分别移植于挫伤灶中心和挫伤灶边缘；在TBI后的28d内采用钉板平衡木行走测试大鼠运动功能变化，运动功能检测结束后取出脑组织行组织学检测。结果 治疗组滑落脚步数明显少于对照组（P〈0．05）；移植的HACs呈蓝色荧光；部分移植HACs可见MAP-2阳性表达。结论 移植HACs使大鼠TBI后运动功能明显改善。     

MRV检测脑静脉窦血栓的作用

目的探讨磁共振静脉血管成像(MRV)用于检测脑静脉窦血栓(CVT)的应用价值。方法8例CVT患者均行MRI标准自旋回波T1WI、T2WI和VEN/3D/PCA。结果VEN/3D/PCA比标准SE序列T1WI和T2WI多检测出CVT3处,与脑血管造影的结果完全相符。结论MRV可以准确无创的诊断CVT。     

EEG dipole analysis of motor-priming foreperiod activity reveals separate sources for motor and spatial attention components

OBJECTIVE: This study employed EEG source localisation procedures to study the contribution of motor preparatory and attentional processing to foreperiod activity in an S1-S2 motor priming task. METHODS: Behavioural and high-density event-related potential (ERP) data were recorded in an S1-S2 priming task where participants responded to S2 with a left or right-hand button press. S1 either provided information about response hand (informative) or ambiguous information (uninformative). RESULTS: Responses were significantly faster in informative trials compared with uninformative trials. Dipole source analysis of foreperiod lateralized ERPs revealed sources of motor preparatory activity in the dorsolateral premotor cortex (PMd) in line with previous work. In addition, two spatial attention components (ADAN, LDAP) were identified with generators in the PMd and occipitotemporal visual areas in the middle temporal (MT) region, respectively. Separation of motor-related and attentional PMd source locations was reliable along the rostral-caudal axis. CONCLUSIONS: The presence of attentional components in a motor priming paradigm supports the premotor theory of attention which suggests a close link between attention and motor preparatory processes. Separation of components in the premotor cortex is in accord with a functional division of PMd into rostral (higher-order processing) and caudal (motor-related processing) areas as suggested by imaging work. SIGNIFICANCE: A prime for response preparation is a trigger for separate, but closely linked, attention-related activity in premotor areas.     

大鼠脑损伤局部谷氨酸的异常释放对乳酸含量变化的影响

目的探讨谷氨酸(Glu)在大鼠脑损伤局部的异常释放以及其对乳酸(Lac)含量变化的影响。方法采用大鼠局部脑损伤动物模型,分为对照组、损伤组、干预组。伤前15min干预组注射Riluzole(一种Glu突触前释放抑制剂),损伤组注射等容量的生理盐水,对照组仅开骨窗不损伤脑。应用微透析技术检测各组伤后不同时间透析液中Glu含量([Glu]d)及Lac含量([Lac]d)变化。结果[Glu]d及[Lac]d在伤后15min、30min和45min干预组明显低于损伤组(P<0.05),而明显高于对照组(P<0.05);在伤后60min,损伤组仍明显高于对照组(P<0.05)。伤后不同时间[Glu]d和[Lac]d变化呈显著正相关(P<0.01)。结论脑损伤后受损脑组织细胞液中Glu水平的升高是Glu神经元末梢大量释放Glu所致,并继而引起了Lac的含量升高。