额、枕部直接冲击导致脑挫裂伤的力学机制研究

目的 分析额、枕部直接冲击时脑组织的应力响应，探讨颅脑直接冲击导致脑挫裂伤的力学机制。方法 利用头颅三维有限元模型，模拟计算8个不同方向额、枕部冲击载荷下脑组织应力应变响应，图形输出脑表面应力计算结果，分析不同载荷下，脑组织应力改变范围及大小，总结脑挫裂伤致伤机制。结果 直接冲击作用于顶颅时，其造成冲击方向上脑表面von Mises应力升高，这包括冲击对侧脑的表面。上述计算结果与临床额、枕部冲击伤的影像学发现相一致。背向前、中颅底或枕部后颅窝骨壁的冲击可造成相应区域脑表面应力显著升高。结论 由于颅骨、脑组织材料特性不同，在冲击中的两者变形不一致，即颅骨先变形先停止，脑组织后变形后停止，这造成颅骨与脑组织在冲击方向上发生显著相对位移，导致脑表面应力改变，当应力改变超过脑组织耐受时出现脑挫裂伤。这是脑挫裂伤的一种致伤机制。     

额颞部对冲性脑损伤的手术治疗

额颞部对冲性脑损伤是临床上比较常见的一种严重的颅脑损伤，往往表现为一侧额颞叶脑挫裂伤或双侧额叶脑挫裂伤，常伴脑内或硬膜下血肿，有时合并以外侧裂池为主的蛛网膜下腔出血，如处理不当，可导致脑疝发生，危及患者生命。我院2000年1月至2004年12月对96例此类患者采取手术治疗。取得良好效果，现报告如下：     

改良翼点入路治疗严重对冲性额颞部脑损伤

目的 提高严重对冲性脑损伤的治疗效果。方法 我院自1997～2002年采用改良翼点入路治疗32例严重额颞部对冲伤患者。结果GOS-Ⅴ～Ⅲ级56.3％,Ⅱ级6.3％,Ⅰ级(死亡)37.5％。结论 改良翼点入路可显著提高疗效,降低死亡率。     

脑出血的脑损伤机制研究进展

本文综述了脑出血后脑损伤的病理生理变化,包括血肿扩大及占位效应、血凝块的毒性作用及其导致的脑水肿、局部脑血流的改变,旨在为临床研究提供依据。     

全脑缺血后脑损伤的机制

心跳骤停(CA)、休克、窒息以及心脏手术等可发生全脑缺血,除血液灌注不足引起其他器官损害外,脑损伤后出现多种神经学并发症,包括昏迷、癫癎发作、缺血性卒中、精神障碍和认知损害.CA后缺血性脑损伤最常见机制是全身血液灌注不足引起全脑缺血.除脑缺血的病因学外,细胞和分子过程触发的级联反应是导致神经元损伤的"最后共同通路".本文就目前全脑缺血后的脑损伤机制做一综述.     

液压冲击脑损伤大鼠脑皮层IκBα的表达研究

目的 研究大鼠液压冲击脑损伤时KB抑制蛋白仅（inhibitorysubunitofNF．KB，IKBa）表达变化规律。方法 将60只SD大鼠随机分为两组：损伤组：48只大鼠行液压冲击打击，制作大脑损伤模型。对照组：12只大鼠仅行颅骨钻孔术。使用免疫组化及western blot分别测定大脑皮层细胞浆内IKBa的表达变化情况。免疫组化以细胞浆出现棕黄色颗粒为阳性结果，westernblot以醋酸纤维素膜上出现棕色条带为阳性结果。结果 损伤后1h，IKBa表达开始下降，12h降到最低点，损伤后24h表达开始回升，5d逐步恢复正常。结论 IKBa活性变化可作为急性创伤性颅脑损伤时炎症反应程度的一项观测指标，通过抑制IKBa磷酸化降解环节，可发现一条抑制炎症反应的新途径。     

雌激素对缺血性脑损伤作用机制的新进展

近年来临床和基础研究证实雌激素(estrogen,E)具有神经保护作用,其对缺血性脑损伤状态下神经细胞的作用也得到了广泛的关注,但其在中枢神经系统中的作用机制还有待于进一步阐明。现就雌二醇的研究进展综述如下。     

大鼠头颅侧向旋转脑损伤模型脑干听觉诱发电位的变化

目的探讨头颅侧向旋转致脑损伤大鼠模型脑干听觉诱发电位（BAEP）的变化及机制。方法成年大鼠20只，制作头颅瞬间侧向旋转脑损伤模型，测量头颅旋转前及旋转后6h的BAEP，测量电极置于颅顶左侧c2点，左耳予短暂click声刺激，右耳持续予噪声掩蔽，经1000次叠加平均，记录BAEP各波形的潜伏期、波间期和波幅值。结果大鼠头颅旋转后6h和Ⅴ波潜伏期、Ⅰ～Ⅲ和Ⅲ～Ⅴ波波间期明显较旋转前延长，Ⅰ和Ⅴ波波幅较旋转前明显降低，而旋转前后Ⅰ波潜伏期、Ⅰ～Ⅴ波波间期以及Ⅰ波波幅无显著差异。结论头颅瞬间侧向旋转可引起BAEP异常，此与脑干内特殊传导通路的破坏有关，其结构基础为脑干广泛神经轴索损伤。     

炎症反应在脑出血后继发性脑损伤中作用机制的研究进展

正脑出血是第二大卒中类型,病死率和致残率高~([1])。目前,脑出血仍然没有统一规范的确切治疗方法。脑出血引起脑损伤的机制仍然不清楚,许多研究表明炎症反应在脑出血继发性脑损伤过程中有重要作用,调控炎症反应有助于减轻继发性脑损伤、脑水肿,改善神经功能障碍~([2,3])。本文就炎症反应在脑     

额颞部重度颅脑损伤扩大翼点入路手术治疗分析

目的探讨扩大翼点入路治疗额颞部重度颅脑损伤的临床价值。方法48例额颞部重度颅脑损伤患者均采用扩大翼点入路手术治疗方法。扩大翼点入路即在翼点入路基础上扩大暴露范围，包括额底、颞底及额颞顶较大范围。扩大翼点入路结合硬膜扩大缝合，有时采用浮动骨瓣等方法。结果康复良好20例（41．6％），中度残废9例（18．8％），重度残废7例（14．7％），植物生存4例（8．3％），死亡8例（16．7％），死亡原因为严重脑干损伤、休克、严重脑肿胀及呼吸、循环衰竭。结论扩大翼点入路手术治疗额颞部重度颅脑损伤是比较理想的入路，可减少死亡率和伤残率，提高生存质量。     

重型颅脑损伤术中急性脑膨出原因及处理

目的总结重型颅脑损伤开颅术中发生急性脑膨出的原因及处理。方法对近年我科收治的重型颅脑损伤开颅术中发生急性脑膨出的原因及疗效进行回顾性分析。结果几年来共收治310例GCS3～8分手术的重型颅脑损伤病人,开颅术中发生急性脑膨出29例（9．4％）,因急性脑肿胀引起10例（34．5％）,因迟发性血肿引起18例（62．1％）,其他原因1例（3．4％）;其中急性脑肿胀者死亡10例（34．5％）,迟发性血肿者死亡6例（20．7％）,总死亡16例（55．2％）,植物生存2例（6．9％）,重残3例（10．3％）,轻残5例（17．2％）,恢复正常生活者3例（10．3％）。结论急性脑肿胀与迟发性血肿引起的脑膨出预后不同,前者死亡率几乎达100％,而远隔部位迟发性血肿只要处理及时,预后良好。     

重型颅脑损伤患者亚低温治疗的临床研究

目的 通过比较重型颅脑损伤患者亚低温治疗组与常温治疗组的预后来证实亚低温治疗的脑保护作用. 方法 选取重型颅脑损伤患者76例(GCS≤8分),分为亚低温治疗组(36例)和常温治疗组(40例).常温治疗组患者应用脱水降颅压、营养神经、止血、抑制胃酸分泌、营养支持等常规治疗.亚低温治疗组患者除常规治疗外,合并应用冰毯实行亚低温治疗(患者躺在冰毯垫上,通过体表散热使中心体温和脑温降至所需温度,通常为32～34℃,并根据病情需要维持3～14 d).结果亚低温治疗组患者预后优于常温组,差异有统计学意义(P<0.05). 结论 亚低温治疗对重型颅脑损伤患者具有脑保护作用,能提高临床疗效,值得推广应用.     

CT中脑背侧脑池出血对原发性脑干损伤的早期诊断价值

目的 分析颅脑外伤急诊CT中脑背侧脑池出血的表现,探讨其对临床原发性脑干损伤的早期诊断价值.方法 回顾性分析52例颅脑外伤患者临床表现及影像学资料,并依据GCS评分分为轻、中、重及特重型.所有患者均在伤后48 h内接受CT检查,CT采用常规程序扫描.MRI检查则根据病情变化在伤后1周内完成,采用自旋回波T1WI、T2WI序列.结果 所有病例的CT表现均与MRI的T1WI、T2WI序列行比较研究,其中39例颅脑损伤患者的急诊CT有中脑背侧环池或四叠体池出血表现,合并弥漫性脑肿胀19例,脑实质出血灶单发或多发点状出血灶11例,直径小于2 cm;37例MRI检查存在不同程度的脑干组织损伤表现.结论 重型和特重型颅脑外伤(GCS<9分)伤后早期CT的中脑背侧脑池出血表现高度提示原发性脑干损伤可能,对提高原发性脑干损伤早期诊断水平具有重要的参考价值.     

Brief compassion focused imagery for treatment of severe head injury

Objective: To determine whether participants with severe head injury (SHI) allocated to a brief compassion focused imagery (CFI) intervention show greater change in compassion than those exposed to relaxation imagery (RI).

Method: Participants were exposed to a preparatory video to promote engagement and then randomly allocated to intervention. Pre- and post-preparatory measures were Motivation for Intervention and Fears of Compassion Scales, State-Trait Anxiety Inventory (STAI) and PANAS. Pre- and post-intervention self-report measures were the Empathy Quotient, Self-Compassion Scale, STAI and Relaxation Scale. Heart rate variability (HRV) was monitored throughout.

Results: Motivation for therapy increased after the preparatory video (z?=?3.44, p?=?0.001). Across the intervention, group differences were not found on self-report measures or HRV changes. When CFI and RI groups were pooled, improvement in relaxation (r?=?.41, p?<?0.01) and state anxiety (r?=?.29, p?<?0.05) were found across the intervention; these outcomes were not associated with changes in self-compassion or HRV.

Conclusion: Brief CFI, a central aspect of compassion focused therapy, did not produce a reliable change in people with SHI. Enhanced motivation for psychological therapy after a brief preparatory video is relevant and underlines the need to understand mechanisms of action rather than the pursuing whole protocol approaches to therapy.     

The changing “epidemiology” of pediatric head injury and its impact on the daily clinical practice

Aim  This article focuses on the developments that occurred during the last two decades in the management of pediatric head injury. It describes the changes in incidence, various advancements in diagnosis, management, prognosis, prevention and strategies required for better outcome, and control of head injury. Materials and methods  Thorough evaluation of various papers, research, and our experience revealed that in developed countries, there has been a decreasing trend in head trauma incidence and trauma-related deaths as compared to developing countries. Results  This is mainly attributed to the widespread implementation of preventive measures. The development in imaging facilities, better characterization and grading of severe trauma (see, for example, diffuse axonal injury), an advanced understanding of the pathophysiology of secondary brain injury, endocrinological disturbances, predictive factors of outcome, development in neurophysiological monitoring, management advances in critical care units, implementation of safely measures, etc. have brought a significant change in overall outcome and profile of pediatric head injury Conclusion  The further developments in field of brain plasticity, stem cell, rehabilitation, evolution of new drugs, preventive community measures, and global policies to deal with head trauma are expected to play a major role in days to come. The development of future pediatric trauma centers based on current evolutions (in order to achieve a good outcome), global and emphatic preventions of trauma will be required to establish equilibrium between developed and developing countries.     

The dynamic triple peak impact factor in traumatic brain injury influences native protein structures in gray and white matter as measured with computational simulation

Abstract

Background: Traumatic brain injuries (TBIs) cause a substantial burden to the patient, relatives, and the society as a whole. Much experience and knowledge during the last two decades have improved the neurosurgical treatment as well as the outcome. However, there is still much debate on what actually happens when external kinetic energy is transferred to the head immediately after a TBI. Better knowledge about the cascades of mechanical events at the time of accident is a prerequisite to further reduce the burden in all categories and improve the neurosurgical care of TBI patients.

Methods: In the present study, we use the finite element modeling of the human brain to numerically simulate impact velocities of 10, 6, and 2 m/s to clarify some of the immediate consequences of the external kinetic energy transfer focusing on the gray (GM) and white matters (WM).

Results: The numerical simulation was focused on the external kinetic energy transfer with a level of 227·3 J reaching the head, intracranial pressure (ICP), strain energy density, 1st principal strain level, and their respective impacts on the brain tissue. The results show that, for a 10 m/s impact, a total internal potential energy of 208·6 J was absorbed, of which 14·3% (29·81 J) was absorbed by the scalp, 22·05% (46·0 J) by the outer compact bone, 17·12% (35·72 J) by the porous bone, 27·44% (57·23 J) by the inner compact bone, and 7·31% (15·24 J) by the facial bone. The rest of the internal potential energy was defined to reach the GM (3·6%, 7·51 J) and the WM 1·59% (3·31 J). Also, the ICP, strain energy density, and 1st principal strain levels, defined as the dynamic triple peak impact factor, influenced the GM and WM with their own impact peaks during the first 10 ms after the accident and were the highest for the 10 and 6 m/s impacts, while the 2 m/s impact had only a slight influence on the GM and WM structures.

Conclusions: The present study shows for the first time that following an impact of 10 m/s, 88·31% of the calculated external kinetic energy was absorbed by the external parts of the head before the remaining energy of 5·19% reached the GM and WM. GM absorbed about twice as much of the energy compared to the WM. It is suggested that the dynamic triple peak impact factor may have a profound effect on native protein structures in the cerebral metabolism after a TBI.     

Application of finite element analysis in neurosurgery

With the rapid development of computer equipment, approximation by analytical solutions has become popular in mathematical modeling. Finite element (FE) analysis uses numerical methods to solve problems with physical phenomena, and these can be applied to various geometrically complex materials, such as brain. The FE formulation can provide such diverse domains as heat conduction, torsion of elastic material, diffusion and fluid flow, and it can view different objects of study in the neurosurgical field. In this article, the various applications of FE methods are introduced to illustrate the usefulness of the technique and the link between the external biomechanical aspect and internal phenomena in brain research. Received: 15 November 1999     

健康人体正常站立位完整股骨生物力学的有限元分析

建立完整的正常人股骨三维有限元模型，并应用于正常站立位生物力学分析。基于序列CT断层扫描图像，应用逆向工程原理，用自编图像处理程序从图像提取点云，并在逆向工程软件和有限元分析软件中建立有限元模型。其中将模型中材料考虑为连续、均质、各向同性的线弹性材料，将皮质骨和松质骨材料参数综合等效为弹性模量12 GPa，泊松比是0.3。模拟正常双足站立，股骨头上表面受到垂直向下的分力为500 N，执行计算。结果成功建立了有限元模型，最大位移发生在股骨头，最大应力发生在股骨体中下段，为14.2 MPa，股骨颈局部拉应力较大。验证了股骨骨折多发于股骨体中下段的理论；并证明了老年人多发股骨颈骨折，并且骨折难愈合的事实，从生物力学角度说明股骨颈骨折后应避免活动。