Proton magnetic resonance spectroscopy and intracranial tumours: Clinical perspectives

Proton magnetic resonance spectroscopy (1H-MRS) was applied to characterize intracranial tumours of different hystological types. Seventy patients with intracranial neoplasms were studied before receiving surgery, radiotherapy or chemotherapy. All tumours were characterized by reduced or absentN-acetylaspartate and increased signal from choline-containing compounds. Distinctive patterns were observed only for primitive brain neoplasms; high-grade gliomas were differentiated from low-grade ones by higher levels of choline-containing compounds. The metabolic aspects of metastatic lesions were similar to high-grade gliomas. These results, together with the limitations of¹HMRS and future applications are reviewed.     

脑梗死患者脑白质病变及其危险因素

目的 探讨脑梗死患者脑白质病变(white matter lesions,WML)患病情况及其危险因素.方法 采用多中心横断面研究和病例-病例对照研究.收集全国12家医院2004年5月至12月连续就诊的1～6个月内脑梗死患者720例的临床资料.分别对头MRI显示的脑梗死部位、大小、血管分布、血管类型做出判断,用年龄相关性白质改变评分法(Age-Related White Matter Changes Scales,ARWMC)测量脑白质病变,阅片者不了解患者的临床资料.采用Logistic回归检验独立危险因素.结果 MRI图像质量完好700例[平均年龄(59.93±9.86)岁,男/女为481/219],WML患病率77.4%,随年龄增长患病率和病变严重程度增加.额叶病变最多,程度最重.Logistic回归显示高龄(OR 1.09,95% CI 1.067～1.114)、舒张压升高(OR 1.039,95% CI 1.018～1.06)、基底节梗死(OR2.244,95% CI 1.609～3.708)与WML存在独立相关.结论 脑梗死患者WML普遍存在.病变以额叶最明显.高龄、舒张压升高、基底节梗死是发生WML的独立危险因素.     

The distribution of normal brain water content in Wistar rats and its increase due to ischemia

The aim of this study was to describe the normal distribution of the water content in several regions of the rat brain and furthermore to determine if global ischemia results in a variable increase in water content in these regions. Water content was determined in 40 regions: in 8 unaffected brains by gravimetry and in 9 unaffected brains by estimation of the wet/dry weight ratio. In addition, 6 rats underwent 6 h of moderate global brain ischemia in order to evaluate the sensitivity of the investigated brain areas to develop a cytotoxic brain edema. The impermeability of the blood-brain barriers to proteins was evaluated by staining with Evans blue. Physiological differences in water content between the several brain regions ranged from 72.57 ±0.77% (mean ± S.D.) in the medulla oblongata to 84.83 ± 0.52% in the hypothalamus. Generally, the water content of the grey matter was higher than that of the white matter and increased from the frontal to the occipital and from the parietal to the basal cortex. Even adjacent cortical regions showed differences in the amount of brain water of up to 3.41%. In the ischemic animals, the impermeability of the blood-brain barrier to proteins was not compromised, but an increase in the amount of brain water was found in the frontoparietal cortex of 1.17 ± 0.37% and hippocampus of 1.49 ± 0.39% (P < 0.05). This ischemic increase in the brain water content was small in comparison to the normal variance in regional brain water content. Similar results were obtained by determining the wet/dry weight ratio and by gravimetry. Gravimetry led to more consistent results. In conclusion, the study shows great differences in normal water content between the several brain areas in comparison to an only slight increase of water content due to the development of cytotoxic brain edema. The determination of an early state of an increased brain water content requires an adequate and differentiated measurement of different brain areas. The gravimetry fulfills this demand.     

Brain abscess in infants and children

Forty-four consecutive patients with brain abscesses, aged between 1 month and 16 years, were reviewed. The cause of abscess was menigitis in 36% of the cases, otitis in 27%, heart disease in 9%, other in 5%, and undetected in 5%. Thirty patients had a single abscess and 12 had multiple abscesses. Multiloculated abscess was present in 2. Total excision was accomplished in 22 patients. Three patients underwent needle aspiration. Drainage of the abscess was performed in 13. Secondary excision was needed in 5 patients. One patient was treated nonsurgically. Streptococci, staphylococci and Proteus mirabilis were the microorganisms recovered in cultures. Overall mortality was 20% (9 patients). Mortality was significantly higher in patients under 2 years of age than in those older. Of 15 patients who were comatose at the time of admission, 6 died. Etiology, diagnostic method, and treatment modalities were not found to be significant factors in terms of predicting mortality.     

Correspondence between development of cytotoxic edema and cerebrospinal fluid volume and flow in the third ventricle after ischemic stroke

ObjectivesThe importance of monitoring cerebrospinal fluid for the development of edema in ischemic stroke has been emphasized; however, studies on the relationship between intraventricular cerebrospinal fluid behavior and edema through longitudinal observations and analysis are rare. This study aimed to investigate the correlation between the development of cytotoxic edema and cerebrospinal fluid volume and flow in the third ventricle after ischemic stroke.Materials and methodsThe ventricle and edema regions were obtained using apparent diffusion coefficients and T₂ and subdivided into lateral/ventral 3rd ventricles and cytotoxic/vasogenic (or cyst) edema, respectively. In rat models of ischemic stroke, the volume and flow (via the pseudo-diffusion coefficient [D*]) of the ventricles and edema volumes were longitudinally monitored for up to 45 days after surgery.ResultsThe volume of cytotoxic edema increased in the hyperacute and acute phases, whereas the volume (r = -0.49) and median D* values (r = -0.48 in the anterior-posterior direction) of the ventral 3rd ventricle both decreased, showing negative correlations with the volume of cytotoxic edema. In contrast, the volume of vasogenic edema/cyst was positively correlated with the volume (r = 0.73) and median D* values (r = 0.78 in the anterior-posterior direction) of the lateral ventricle in the subacute and chronic phases.ConclusionsThis study showed that the evolution of cerebrospinal fluid volume and flow in the ventricles was associated with edema progression at different time points in the ischemic stroke brain. This provides an efficient framework for monitoring and quantifying the interplay between cerebrospinal fluid and edema.     

Delayed cerebral pseudo-tumoral radionecrosis following scalp-tumour irradiation. Case report and review of literature

Summary A case of delayed radionecrosis of the brain is reported, following irradiation of a scalp dermatofibrosarcoma. Signs and symptoms were those of an intracranial neoplasm and appeared 5 years after an irradiation dosage of 1890 rets. Twenty-seven similar cases were gathered from a survey of the literature. Surgical excision was the treatment of choice and led to cure or improvement in 20 cases. Analysis of doses and fractionation revealed excessive irradiation in all but one of the cases.     

颅脑损伤后AQP-4在脑组织中表达与脑水肿的关系

目的探讨水通道蛋白-4（AQP-4）在急性颅脑损伤早期脑水肿发生中的作用。方法应用免疫组织化学方法检测人脑组织中AQP-4的表达。创伤组标本取自28例急性颅脑损伤患者急诊开颅血肿清除时所获挫伤灶周围脑组织；对照组取自8例原发性癫痫患者手术切除的相对正常脑组织。结果急性颅脑损伤后早期挫伤灶周围脑组织有明显的脑水肿发生，AQP-4的表达水平明显高于对照组（P〈0．01），且其表达主要见于小血管及神经胶质细胞。结论AQP-4表达的早期上调与急性颅脑损伤后脑水肿的发生有密切的关系。     

Brain Interstitial Fluid and Intracellular Distribution of Phenytoin

After intravenous (i.v.) administration (10 mg/kg), the biodisposition of phenytoin (PHT) in serum (total and free concentration), cerebrospinal fluid (CSF), brain, and the interstitial fluid (IF) of the normal brain were determined in dogs. A sufficient volume of IF was obtained through a multiperforated polypropylene ball implanted into the left parietotemporal region for 4-5 weeks. PHT brain distribution coefficient values ranged between 1.9 and 3.75, while the ratios of IF to free serum PHT concentrations ranged between 0.19 and 1.04; thus, our data indicate that most of the free unbound PHT which enters the brain parenchyma accumulates in the cellular compartment. Furthermore, at 60 and 90 min the peak CSF and IF concentrations are delayed; thus, for PHT, an apparent diffusion front from the CSF into the extracellular space of the brain seems to occur.     

慢性精神分裂症与脑肿瘤患者认知状况比较分析

目的　探讨慢性精神分裂症患者脑功能缺陷与不同脑叶损伤间的关系。方法　运用威斯康星卡片分类测验、词汇流畅性测验、Stroop测验,对30名正常人、39例精神分裂症及88例脑肿瘤患者(其中左、右额叶各2 4例、颞叶2 0例、顶枕叶2 0例)进行测试。结果　精神分裂症患者与脑肿瘤患者均存在不同程度、不同特征的认知损伤,其中阴性症状为主的精神分裂症与右额叶脑肿瘤患者损伤类似,除完成分类数、总词汇数外,本研究所采用的测查其余指标差异无显著性(P >0 . 0 5)。结论　阴性症状为主的慢性精神分裂症患者右侧额叶功能受损明显,精神分裂症起病的器质性因素可能涉及右额叶。     

脑肿瘤放疗后假性进展的诊断及治疗(附14例报告)

目的 探讨脑肿瘤放疗后假性进展的诊断及治疗方法 .方法 通过分析14例脑胶质瘤放疗后假性进展患者的临床资料,结合当今有关脑肿瘤假性进展的研究,对脑肿瘤假性进展的诊断和治疗进行分析总结.结果 本组病例中以放疗不当为脑肿瘤假性进展的主要原因,以头痛为首发症状,可伴有神经功能缺失,糖皮质激素治疗对11例患者有效,对于治疗效果不明显的3例患者,采用二次手术切除病灶,组织病理学检查证实为脑组织坏死.结论 脑肿瘤放疗后假性进展的诊断应综合分析患者的临床资料、PET和MRS检查的结果 ,治疗以糖皮质激素为主.     

脑肿瘤放疗后假性进展的诊断及治疗(附14例报告)

目的 探讨脑肿瘤放疗后假性进展的诊断及治疗方法 .方法 通过分析14例脑胶质瘤放疗后假性进展患者的临床资料,结合当今有关脑肿瘤假性进展的研究,对脑肿瘤假性进展的诊断和治疗进行分析总结.结果 本组病例中以放疗不当为脑肿瘤假性进展的主要原因,以头痛为首发症状,可伴有神经功能缺失,糖皮质激素治疗对11例患者有效,对于治疗效果不明显的3例患者,采用二次手术切除病灶,组织病理学检查证实为脑组织坏死.结论 脑肿瘤放疗后假性进展的诊断应综合分析患者的临床资料、PET和MRS检查的结果 ,治疗以糖皮质激素为主.     

创伤性脑水肿脑组织乳酸及线粒体SOD,MDA水平的变化

目的 淡研究脑损伤后挫裂伤灶旁局部脑组织乳酸代谢及线粒体ＳＯＤ、ＭＤＡ变化和脑水肿的关系，以进一步探讨其在脑损伤后不同时期的影响。方法 以自由落体脑创伤为模型，采用生化检测的方法对伤后４ｈ、２４ｈ、４８ｈ不同时间大鼠伤侧大脑皮质乳酸及线粒体ＳＯＤ活力、ＭＤＡ的含量测定，用干湿重法测相应时间脑组织含水量。结果 在伤后４ｈ脑组织含水量即增加，并且随着乳酸及线粒体ＳＯＤ、ＭＤＡ含量的改变而发生变化、与对     

Effects of maternal dietary protein restriction on growth of the brain and body in the rat

We studied the growth of the brain and body in rats born of dams fed a low-protein (8% casein) diet ad lib beginning 5 weeks prior to mating and continuing throughout gestation and lactation. Control dams were fed an isocaloric 25% casein diet. Litters were culled at birth to 8 pups. At birth, brain weights and body weights of pups of protein restricted dams were similar to those of control pups. During the period of lactation, pups of restricted dams exhibited severely retarded body growth but only mildly retarded brain growth resulting in an elevated brain/body weight ratio. This relative macroeephaly was maximal at 10–20 days of age, declining completely by 35 days of age. The relative macroeephaly could not be accounted for by increased retention of water in the brains of the malnourished rats. Following weaning, pups were maintained ad lib on the diets fed their mothers. At adulthood brain/body weight ratios were normal in the protein restricted group.     

依达拉奉对颅脑损伤病人脑水肿及预后的影响

目的探讨依达拉奉对颅脑损伤病人脑水肿及预后的影响。方法采用随机双盲平行对照试验,98例急性颅脑损伤的病人随机分成治疗组50例和对照组48例,对照组按照急性脑损伤常规治疗,治疗组在常规治疗的基础上给予依达拉奉注射液30mg加入生理盐水注射液100ml中静滴,bid,共14d。2组在治疗后3、7、14、28d做头部CT检查,根据脑CT显示脑水肿最大层面的长×宽测算脑水肿面积表示脑水肿的程度,观察脑水肿的变化。于治疗前和治疗后28d分别进行格拉斯哥昏迷评分(GCS)。结果2组病人伤后脑水肿均逐渐加重而至第7d达高峰期,在第7d前2组脑水肿变化比较无统计学意义(P>0.05)。从第14～28d2组病人均明显减轻,但治疗组脑水肿减轻程度明显优于对照组(P<0.01);2组在第28dGCS评分均有提高,但治疗组GCS评分明显高于对照组(P<0.05)。依达拉奉治疗期间未发现明显不良反应。结论依达拉奉可以减轻颅脑损伤病人脑水肿,并能改善预后,无明显不良反应。     

CT-guided stereotactic biopsies of brain stem lesions: personal experience and literature review

Abstract. Appropriate therapy of brain stem lesions should be guided by an accurate diagnosis. Clinical evaluation combined with modern neuroimaging techniques may nowadays approach the diagnosis but not always with accuracy, thus leading to erroneous treatment. We report a series of 11 patients who underwent stereotactic biopsy for brain stem lesions. In 8 patients, the lesion was approached transfrontally. In the remaining 3 patients, the lesion was approached via the suboccipital transcerebellar route. There was no surgical mortality. Precise histological diagnosis was achieved in all patients. Three patients (27.2%) suffered complications attributed to the procedure and were successfully treated conservatively. Histological results were in accordance with preoperative diagnosis in 9 patients (81.8%). Despite the limited number of patients, our data suggest that stereotactic biopsy of brain stem lesions is a safe technique that can obtain adequate tissue for histological diagnosis, thus providing each patient with the best available treatment.     

Traumatically induced axonal damage without concomitant change in focally related neuronal somata and dendrites

Summary Traumatic head injury has long been associated with the genesis of reactive axonal change, which many believe to be a major factor in influencing neurological outcome. Although much significance has been attached to such a traumatically induced axonal change, little information exists as to whether such a reactive change occurs as an isolated event or rather as an event associated with concomitant focal tissue damage, possibly involving related neuronal somal and dendritic elements. This issue was critically assessed in mechanically brain-injured cats in which the anterograde axonal transport of horseradish peroxidase was employed to detect reactive axonal change. Following such traumatically induced reactive axonal change over a 21-day post-traumatic period, altered axons were consistently observed within the red, vestibular and reticular nuclei and any evidence for concomitant change within the related neuronal somal and dendritic elements was assessed using light and electron microscopy. Typically, such axonal change occurred without any evidence of focally related somatic or dendritic alteration. Isolated examples of reactive axons approximating neurons undergoing chromatolysis were observed. However, such neuronal chromatolytic change appeared not to be a primary response to trauma, but rather a response secondary to severence of these neurons' axonal projections. The results of this study demonstrate that, in mild to moderate head injury, reactive axonal change does occur in isolation from other forms of focal parenchymal abnormality. This finding, therefore, emphasizes the concept that the number of axons damaged is most likely related to the magnitude of any ensuing neurological abnormality.Supported by NIH grants NS 12587 and NS 20193 designated as a Javits Neuroscience Investigator Award     

外伤性脑水肿神经元胞浆游离钙浓度及Ca~(2+)—ATP酶活性变化

本文研究大鼠脑损伤后皮质神经元突触体胞浆中游离钙浓度([Ca~(2+)]i),Ca~(2+)—ATP酶活性及脑组织水含量变化。并选用脑活素治疗,观察其对神经细胞Ca~(2+)超载及Ca~(2+)—ATP酶活性改变和脑水肿的影响。结果:脑损伤后神经元Ca~(2+)通道开放,伤后仅0.5小时,突触体胞浆中游离[Ca~(2+)]i已升高至1095.42±76.15nmol/L水平,为对照值的10倍;伤后6,24,48和72小时,[Ca~(2+)]i持续处于高水平,为对照值的16～17倍。与之相反,神经细胞线粒体Ca~(2+)—ATP酶活性显著下降。脑损伤后脑组织水含量增加,以脑白质增加较为明显。应用脑活素治疗后,线粒体Ca~(2+)—ATP酶活性有明显回升,神经元胞浆Ca~(2+)超载有所减轻,脑水肿有一定改善。     

弥散张量成像在颅内环形强化病变中的诊断价值

目的 探讨弥散张量成像(diffusion tensor imaging,DTI)对颅内环形强化病变的诊断价值.方法 53例颅内单发环形强化病例术前行DTI扫描,分别测量病变坏死区、灶周水肿区及对侧正常脑实质的平均弥散系数(MD)值及各向异性分数(FA)值.并通过弥散张量纤维束成像(diffusiontensor tracking,DTT)观察病灶与白质纤维束的关系.结果 脑脓肿坏死区的MD值为(0.60±0.13)×10-3 mm2/s,FA值为0.18±0.03,高级别星形细胞瘤MD值为(2.76±0.26)×10-3mm2/s,FA值为0.07±0.02,脑转移瘤MD为(2.82±0.29)×10-3mm2/s,FA值为0.06±0.02,前者与后两者间差异有统计学意义(P<0.01).高级别星形细胞瘤水肿区的FA值(0.23±0.06)与脑转移瘤(0.17±0.06)和脑脓肿(0.15±0.03)两者水肿区FA值差异有统计学意义(P<0.01).DTT可以较准确地反映病灶与白质纤维束的关系,为手术治疗及评估预后提供依据.结论 坏死区MD值及FA值有助于脑脓肿与环形强化脑肿瘤的鉴别;水肿区FA值有助于脑星形细胞瘤与转移瘤、脑脓肿的鉴别;DTT能够为优化手术方案及评估预后提供一定帮助.