脑磁图在颅脑损伤中的应用

脑磁图与MRI融合后的磁源成像图在鉴别脑震荡后遗症状的患者是否存在脑功能障碍方面优于EEG或MRI,比EEG或MRI在轻型颅脑损伤中提供的客观依据更敏感,脑磁图磁场活性的异常低频表现为脑震荡后综合征患者提供了一个客观证据,并与症状恢复程度相关。近来研究对严重颅脑损伤后长期昏迷的患者用MEG测量刺激双侧正中神经引起的躯体感觉磁场区域来评估皮质体感功能,认为弥漫性脑损伤导致躯体感觉传入冲动在原躯体感觉皮层减少与延迟,并引起代偿性反应扩张。通过MEG测定的体感诱发区域的中潜伏期对严重颅脑损伤患者是有用的皮层功能测定。     

脑震荡病人恢复期心理状况调查

脑震荡作为轻型颅脑损伤,主要表现为脑的功能障碍,其伤情亦无复杂之处,经适当治疗,各种症状多于数日或数周消失。但由于长期以来在患者及其亲属中所形成的误解或仅仅基于对脑震荡的肤浅了解,一些人不适当地夸大了脑震荡的伤情严重性及其转归,以致对伤员产生了很大的心理影响。本调查尝试了解脑震荡患者受伤１月后的心理健康状况及其影响因素,以便为临床治疗提供依据。１　资料１１　调查对象：调查对象为符合脑震荡诊断［１］并符合下列要求的患者：①曾于近年入院或在门诊治疗;②伤后至接受调查的时间为１个月至２７个月,平均…     

颅脑损伤病人外周血GFAP和UCH-L1研究进展

正常规头颅CT和MRI对鉴别脑震荡、弥漫性轴索损伤和微出血灶不够敏感,而这些损伤又可能发展为震荡后综合征、慢性创伤性脑病。研究表明CT扫描只可以检测到10%的轻型颅脑损伤(traumaticbrain injury,TBI)异常~([1]),常规MRI仅检测到轻型TBI中约32%弥漫性的轴索血管损伤~([2])。脑爆震伤后影     

磁共振弥散张量成像在轻度颅脑损伤患者中弥漫性轴索损伤的应用

弥漫性轴索损伤在轻度颅脑损伤(MTBI)患者及脑震荡后综合征(PCS)的病理生理学过程中发挥重要作用,磁共振弥散张量成像与传统影像学技术相比,能更灵敏地检测出多种类型的大脑白质轴索损伤,为MTBI及PCS的司法鉴定提供客观的医学诊断依据,现就近年来有关研究进展作一综述。     

事件相关电位技术在轻型颅脑损伤病人认知功能障碍评估中的研究进展

正据统计,全世界每年有超过1 000万人遭受颅脑损伤,其中轻型颅脑损伤占70%～90%~([1])。传统观点认为,轻型颅脑损伤一般预后较好。但是,近年来,体育相关(橄榄球、篮球等)和军事作业相关轻型颅脑损伤造成的认知功能障碍和远期影响越来越受到关注。研究证实,轻型颅脑损伤不仅会引起病人脑组织的神经病理改变,而且对病人认知功能也有长期的影响~([2]),包括注意力不集中、记忆力下降和信息处理速度降低~([3])。传统的神经心理评估量表对轻型颅脑损伤认知功能障碍的评估和监测主观波动性大、稳定性差;而且,轻型颅脑损伤症状轻微,常规神     

磁敏感加权成像对脑震荡的诊断价值

目的探讨磁敏感加权成像(suscepetiblity-weighted imaging,SWI)在轻型颅脑损伤脑震荡患者中检测出细小出血灶(microbleeds)的诊断意义。方法 37例颅脑CT检查阴性,考虑诊断为脑震荡的患者应用常规MRI及SWI进行检查(观察组),9例健康体检者也行常规MRI及SWI检查(对照组);分析2组应用常规MRI及SWI检查发现细小出血灶的阳性率、数量及分布。结果观察组37例患者中常规MRI发现细小出血灶者4例(10.8%),出血灶数量11个,SWI发现细小出血灶者11例(29.7%),出血灶数量43个,其中SWI检测出细小出血灶者11例中的7例MRI检查阴性,SWI检测出细小出血灶阳性率及数量明显高于MRI检查,差异有统计学意义(P0.05);对照组常规MRI及SWI均未发现细小出血灶。结论对脑震荡患者应用SWI检测较颅脑CT及常规MRI能更敏感地发现出血性病变,为明确患者的诊断提供影像学证据,具有很高的临床应用价值。     

脑电图监测无CT影像改变的轻型脑伤的临床意义

目的研究脑CT检查为阴性的轻型颅脑损伤的脑电图（EEG）、脑电地形图（BEAM）变化特点及其临床价值。方法对108例轻型颅脑损伤（脑震荡）早期进行动态EEG和BEAM监测。结果无CT影像学改变的轻型脑损伤监测EEG、BEAM有异常改变达88．89％，其中79．17％为异常的0波和8波，伤后3d内测得的阳性显著高于3d后（P〈0．01）。并发现脑生物电异常变化沿受力轴线分布。结论早期反复测定EEG、BEAM变化是反映轻型脑损伤早期脑功能变化定位和伤情分析以及临床诊断治疗效果评判的客观依据。     

磁共振扩散张量成像对轻型颅脑损伤的临床诊断价值

目的探讨磁共振(MR)扩散张量成像(DTI)在轻型颅脑损伤患者诊断中的价值。方法选择轻型颅脑损伤患者(病例组)和健康志愿者(对照组)各40例,病例组再分为有/无认知功能障碍亚组(分别为22例和18例),分别行MR DTI扫描,对病例组进行里蒙德脑震荡后综合征问卷(RPQ)评分,比较两组额叶白质、颞叶白质、内囊、胼胝体的部分异向性(FA)和表观扩散系数(ADC),并比较病例组有和无认知功能障碍患者的上述各项指标。结果病例组和对照组MRI常规扫描和DTI扫描均未见异常信号;病例组和对照组两侧额叶白质、颞叶白质、内囊、胼胝体膝部、压部的ADC值差异均无统计学意义(P0.05);病例组两侧额叶白质、颞叶白质、内囊及胼胝体压部的FA值均低于对照组(P0.05),RPQ评分高于对照组;病例组有认知功能障碍亚组两侧额叶、颞叶FA值低于无认知功能障碍亚组(P0.05)。结论轻型颅脑损伤患者存在脑组织损伤,FA值是判断脑组织损伤的敏感指标,DTI检查为轻型颅脑损伤的临床诊断提供了有力的依据。     

颅脑损伤后综合征对男性勃起功能的影响

目的探讨颅脑损伤后综合征对男性勃起功能的影响。方法在颅脑损伤后6个月对126例男性颅脑损伤患者的颅脑损伤后综合征的发生情况及勃起功能障碍进行问卷式调查,并分析两者之间的关系。结果126例颅脑损伤患者中合并颅脑损伤后综合征45例,有勃起功能障碍者16例（35．56％）;没有合并颅脑损伤后综合征者81例,有勃起功能障碍者2例（2．47％）。两组患者勃起功能障碍发生率相差显著（P〈0．01）。结论颅脑损伤后,若遗留有颅脑损伤后综合征的男性患者,更易发生勃起功能障碍。     

外伤性动眼神经麻痹的临床特点分析

目的总结轻型颅脑损伤所致动眼神经麻痹后的临床特点。方法通过眼外肌运动、眼睑活动、瞳孔大小分析20例轻型颅脑损伤患者动眼神经麻痹的严重程度及功能恢复,随访时间平均为14.2月(3个月~2年)。结果 15名男性患者和5名女性患者纳入此次研究。最常见的外伤原因是交通事故65.4%(13例);眼内肌麻痹是最常见的临床症状;上睑下垂、眼外肌麻痹和眼内肌麻痹的恢复率分别是95%(19例),83.3%(17例)和50%(10例)。结论眼球活动受限是影响轻型颅脑损伤动眼神经麻痹患者生活质量的一个主要因素;蝶骨骨折可能是一个潜在的机制参与了外伤性动眼神经麻痹的发生。     

Contributions of functional magnetic resonance imaging (fMRI) to sport concussion evaluation

Mild traumatic brain injury (mTBI) in contact sport is a problem of such magnitude that improved approaches to diagnosis, investigation and management are urgent. Concussion has traditionally been described as a transient, fully reversible, cerebral dysfunction. However, this seemingly 'mild' injury sometimes results in long-lasting and disabling post-concussion symptoms (PCS) and abnormal neuropsychological profiles characteristic of frontal and/or temporal lobe dysfunction. At present, the pathological changes following concussion remain unclear, but it is now widely accepted that concussion results mainly in functional disturbance rather than structural damage. Therefore, functional imaging techniques can help in demonstrating brain abnormalities undetectable by structural imaging methods. This paper will review the use of functional magnetic resonance imaging (fMRI) in studies of concussion. Our existing and ongoing fMRI studies will be described as examples to highlight the potential and contribution of this non-invasive functional neuroimaging technique in the assessment of sports-related concussion and its management.     

Noninvasive magnetic resonance imaging techniques in mild traumatic brain injury research and diagnosis

Mild traumatic brain injury (mTBI), frequently referred to as concussion, is one of the most common neurological disorders. The underlying neural mechanisms of functional disturbances in the brains of concussed individuals remain elusive. Novel forms of brain imaging have been developed to assess patients postconcussion, including functional magnetic resonance imaging (fMRI), susceptibility‐weighted imaging (SWI), diffusion MRI (dMRI), and perfusion MRI [arterial spin labeling (ASL)], but results have been mixed with a more common utilization in the research environment and a slower integration into the clinical setting. In this review, the benefits and drawbacks of the methods are described: fMRI is an effective method in the diagnosis of concussion but it is expensive and time‐consuming making it difficult for regular use in everyday practice; SWI allows detection of microhemorrhages in acute and chronic phases of concussion; dMRI is primarily used for the detection of white matter abnormalities, especially axonal injury, specific for mTBI; and ASL is an alternative to the BOLD method with its ability to track cerebral blood flow alterations. Thus, the absence of a universal diagnostic neuroimaging method suggests a need for the adoption of a multimodal approach to the neuroimaging of mTBI. Taken together, these methods, with their underlying functional and structural features, can contribute from different angles to a deeper understanding of mTBI mechanisms such that a comprehensive diagnosis of mTBI becomes feasible for the clinician.     

Structural integrity and postconcussion syndrome in mild traumatic brain injury patients

The presence of a postconcussion syndrome (PCS) induces substantial socio-professional troubles in mild traumatic brain injury (mTBI) patients. Although the exact origin of these disorders is not known, they may be the consequence of diffuse axonal injury (DAI) impacting structural integrity. In the present study, we compared structural integrity at the subacute and late stages after mTBI and in case of PCS, using diffusion-weighted imaging (DWI). Fifty-three mTBI patients were investigated and compared with 40 healthy controls. All patients underwent a DWI examination at the subacute (8-21 days) and late (6 months) phases after injury. MTBI patients with PCS were detected at the subacute phase using the ICD-10 classification. Groupwise differences in structural integrity were investigated using Tract-Based Spatial Statistics (TBSS). A loss of structural integrity was found in mTBI patients at the subacute phase but partially resolved over time. Moreover, we observed that mTBI patients with PCS had greater and wider structural impairment than patients without PCS. These damages persisted over time for PCS patients, while mTBI patients without PCS partly recovered. In conclusion, our results strengthen the relationship between structural integrity and PCS.     

Diffusion tensor tractography characteristics of axonal injury in concussion/mild traumatic brain injury

The main advantage of diffusion tensor tractography is that it allows the entire neural tract to be evaluated.In addition,configurational analysis of reconstructed neural tracts can indicate abnormalities such as tearing,narrowing,or discontinuations,which have been used to identify axonal injury of neural tracts in concussion patients.This review focuses on the characteristic features of axonal injury in concussion or mild traumatic brain injury(m TBI)patients through the use of diffusion tensor tractography.Axonal injury in concussion(m TBI)patients is characterized by their occurrence in long neural tracts and multiple injuries,and these characteristics are common in patients with diffuse axonal injury and in concussion(m TBI)patients with axonal injury.However,the discontinuation of the corticospinal tract is mostly observed in diffuse axonal injury,and partial tearing and narrowing in the subcortical white matter are frequently observed in concussion(m TBI)patients with axonal injury.This difference appears to be attributed to the observation that axonal injury in concussion(m TBI)patients is the result of weaker forces than those producing diffuse axonal injuries.In addition,regarding the fornix,in diffuse axonal injury,discontinuation of the fornical crus has been frequently reported,but in concussion(m TBI)patients,many collateral branches form in the fornix in addition to these findings in many case studies.It is presumed that the impact on the brain in TBI is relatively weaker than that in diffuse axonal injury,and that the formation of collateral branches occurs during the fornix recovery process.Although the occurrence of axonal injury in multiple areas of the brain is an important feature of diffuse axonal injury,case studies in concussion(m TBI)have shown that axonal injury occurs in multiple neural tracts.Because axonal injury lesions in m TBI patients may persist for approximately 10 years after injury onset,the characteristics of axonal injury in concussion(m TBI)patients,which are reviewed and categorized in this review,are expected to serve as useful supplementary information in the diagnosis of axonal injury in concussion(m TBI)patients.     

A review of magnetic resonance imaging and diffusion tensor imaging findings in mild traumatic brain injury

Mild traumatic brain injury (mTBI), also referred to as concussion, remains a controversial diagnosis because the brain often appears quite normal on conventional computed tomography (CT) and magnetic resonance imaging (MRI) scans. Such conventional tools, however, do not adequately depict brain injury in mTBI because they are not sensitive to detecting diffuse axonal injuries (DAI), also described as traumatic axonal injuries (TAI), the major brain injuries in mTBI. Furthermore, for the 15 to 30 % of those diagnosed with mTBI on the basis of cognitive and clinical symptoms, i.e., the "miserable minority," the cognitive and physical symptoms do not resolve following the first 3 months post-injury. Instead, they persist, and in some cases lead to long-term disability. The explanation given for these chronic symptoms, i.e., postconcussive syndrome, particularly in cases where there is no discernible radiological evidence for brain injury, has led some to posit a psychogenic origin. Such attributions are made all the easier since both posttraumatic stress disorder (PTSD) and depression are frequently co-morbid with mTBI. The challenge is thus to use neuroimaging tools that are sensitive to DAI/TAI, such as diffusion tensor imaging (DTI), in order to detect brain injuries in mTBI. Of note here, recent advances in neuroimaging techniques, such as DTI, make it possible to characterize better extant brain abnormalities in mTBI. These advances may lead to the development of biomarkers of injury, as well as to staging of reorganization and reversal of white matter changes following injury, and to the ability to track and to characterize changes in brain injury over time. Such tools will likely be used in future research to evaluate treatment efficacy, given their enhanced sensitivity to alterations in the brain. In this article we review the incidence of mTBI and the importance of characterizing this patient population using objective radiological measures. Evidence is presented for detecting brain abnormalities in mTBI based on studies that use advanced neuroimaging techniques. Taken together, these findings suggest that more sensitive neuroimaging tools improve the detection of brain abnormalities (i.e., diagnosis) in mTBI. These tools will likely also provide important information relevant to outcome (prognosis), as well as play an important role in longitudinal studies that are needed to understand the dynamic nature of brain injury in mTBI. Additionally, summary tables of MRI and DTI findings are included. We believe that the enhanced sensitivity of newer and more advanced neuroimaging techniques for identifying areas of brain damage in mTBI will be important for documenting the biological basis of postconcussive symptoms, which are likely associated with subtle brain alterations, alterations that have heretofore gone undetected due to the lack of sensitivity of earlier neuroimaging techniques. Nonetheless, it is noteworthy to point out that detecting brain abnormalities in mTBI does not mean that other disorders of a more psychogenic origin are not co-morbid with mTBI and equally important to treat. They arguably are. The controversy of psychogenic versus physiogenic, however, is not productive because the psychogenic view does not carefully consider the limitations of conventional neuroimaging techniques in detecting subtle brain injuries in mTBI, and the physiogenic view does not carefully consider the fact that PTSD and depression, and other co-morbid conditions, may be present in those suffering from mTBI. Finally, we end with a discussion of future directions in research that will lead to the improved care of patients diagnosed with mTBI.     

Reducing the time interval between concussion and voluntary exercise restores motor impairment,short‐term memory,and alterations to gene expression

Despite the most common form of brain injury, there has been little progress in the prognosis and treatment of concussion/mild traumatic brain injury (mTBI). Current ‘return‐to‐play’ guidelines are conservative, deterring the initiation of physical and social activity until patients are asymptomatic; but the effects of post‐injury exercise have not been adequately investigated. Therefore, this study examined the effects of voluntary exercise on concussion recovery. Using a translational rodent model of concussion, we examined the influence of exercise on injury‐associated behaviours that comprise post‐concussive syndrome (PCS) and gene expression changes (bdnf, dnmt1, Igf‐1, pgc1‐a, Tert) in prefrontal cortex and hippocampus. In addition, as we have previously demonstrated telomere length (TL) to be a reliable predictor of mTBI prognosis, TL was also examined. The results suggest that exercise initiated within 1–3 days post‐concussion significantly improved motor and cognitive functioning, but had limited efficacy treating emotional impairments. What is more, when deprived of social interaction and exercise, a combination similar to clinical recommendations for rest until symptom resolution, animals did not recover and exhibited impairments similar to typical mTBI animals. Exercise aided in restoration of mTBI‐induced modifications to gene expression in both brain regions. An inverse relationship between the exercise return interval and TL was identified, indicating greater recovery with acute exercise reinstatement. Although additional strategies may need to be employed for emotional functioning, these findings support re‐evaluation of ‘return‐to‐play’ guidelines, suggesting that exercise is valuable for the treatment of concussion.     

Diagnostic terminology,athlete status,and history of concussion affect return to play expectations and anticipated symptoms following mild traumatic brain injury

“Mild traumatic brain injury” (mTBI) and “concussion” are terms often used interchangeably. However, “mTBI” is frequently seen as representing a broader injury that encompasses the construct of “concussion,” which often conveys transience or decreased severity. The present study examined the influence of varying diagnostic terminology on acute injury expectations in an undergraduate population (N = 105). Participants were presented with an mTBI vignette and were randomly assigned to one of two conditions in which the term “mTBI” or “concussion” was used to describe the injury. There were no significant differences between the two conditions on anxiety, symptomatology, timeline, or consequence scales. However, participants in the “mTBI” group allocated more days to return to play than participants in the “concussion” group, suggesting that terminology has an effect on perceptions of the severity of the injury. Varsity athletes allocated fewer days to return to play than nonathletes. Individuals with a history of concussion, both athletes and nonathletes, indicated fewer days to return to play, but greater symptomatology than individuals with no history of concussion. Clinicians should consider the influence of diagnostic terminology, athletic background, and history of concussion on perceptions of the severity of an injury because expectations can influence injury outcomes and compliance in a recovery process.     

Central nervous system microbleeds in the acute phase are associated with structural integrity by DTI one year after mild traumatic brain injury: A longitudinal study

Introduction

Several imaging modalities are under investigation to unravel the pathophysiological mystery of delayed performance deficits in patients after mild traumatic brain injury (mTBI). Although both imaging and neuropsychological studies have been conducted, only few data on longitudinal correlations of diffusion tensor imaging (DTI), susceptibility weighted imaging (SWI) and extensive neuropsychological testing exist.

Post concussion syndrome

Individuals sustaining mild traumatic brain injuries often report a constellation of physical, cognitive, and emotional/behavioral symptoms referred to as post concussion symptoms (PCS). The most commonly reported post concussion symptoms are headache, dizziness, decreased concentration, memory problems, irritability, fatigue, visual disturbances, sensitivity to noise, judgment problems, depression, and anxiety. Although these PCS often resolve within one month, in some individuals PCS can persist from months to years following injury and may even be permanent and cause disability. When this cluster of PCS is persistent in nature, it is often called the post concussion syndrome or persistent PCS. Both physiological and psychological etiologies have been suggested as causes for persistent post concussion symptoms and this has led to much controversy and debate in the literature. Most investigators now believe that a variety of pre-morbid, injury-related, and post-morbid neuropathological and psychological factors contribute to the development and continuation of these symptoms in those sustaining mild traumatic brain injury (MTBI).     

Post concussion syndrome

Individuals sustaining mild traumatic brain injuries often report a constellation of physical, cognitive, and emotional/behavioral symptoms referred to as post concussion symptoms (PCS). The most commonly reported post concussion symptoms are headache, dizziness, decreased concentration, memory problems, irritability, fatigue, visual disturbances, sensitivity to noise, judgment problems, depression, and anxiety. Although these PCS often resolve within one month, in some individuals PCS can persist from months to years following injury and may even be permanent and cause disability. When this cluster of PCS is persistent in nature, it is often called the post concussion syndrome or persistent PCS. Both physiological and psychological etiologies have been suggested as causes for persistent post concussion symptoms and this has led to much controversy and debate in the literature. Most investigators now believe that a variety of pre-morbid, injury-related, and post-morbid neuropathological and psychological factors contribute to the development and continuation of these symptoms in those sustaining mild traumatic brain injury (MTBI).