Damage To Brain Parenchyma Research Articles

APOE ∈4 Allele and Chronic Traumatic Brain Injury-Reply

We agree with Dr Gross that a sizable percentage of the professional boxers in our study exhibited abnormalities on neurologic examination. However, our cohort was not randomly selected, and our data cannot be used to accurately estimate the overall prevalence of neurologic impairments in professional boxers. Furthermore, not all abnormal neurologic findings in boxers are indicative of brain injury. Signs and symptoms of chronic traumatic brain injury were mild (12/30) or absent (11/30) in the majority of the boxers we examined. To avoid hyperbole, we recommend that the term significant brain injury be reserved for those instances in which there is actual loss of functional status and/or overt parenchymal brain damage, neither of which was the case with most of the boxers we studied. The purpose of our study was to determine if some boxers are genetically predisposed to chronic neurologic impairments. In our article, we elected not to

Abstracts of Literature

Abstracts of Literature

Correlation between venous stump pressure and brain damage after cortical vein occlusion: an experimental study.

A canine model of cortical vein occlusion was used to evaluate whether data obtained from monitoring venous stump pressure could help predict cerebral infarction after venous obstruction. Following bilateral parasagittal craniotomy, the cortical vein in each hemisphere was temporarily occluded and the increase in pressure was directly measured. Permanent venous obstruction was subsequently produced, and parenchymal brain damage 24 hours later was classified as: Stage 0, no parenchymal damage; Stage I, mild edema; Stage II, moderate parenchymal edema and/or ischemic changes in neurons; and Stage III, moderate-to-severe hemorrhage. The histological stages correlated closely with the rise in venous pressure: mean pressure increases (+/- standard deviation) were 5.5 +/- 2.9 mm Hg in hemispheres graded as Stage 0 (12 hemispheres), 7.7 +/- 3.2 mm Hg in those graded as Stage I (five), 11.2 +/- 4.1 mm Hg in those classed as Stage II (five), and 16.4 +/- 5 in those categorized as Stage III (seven). There were significant differences between Stages 0 and II (p < 0.01) and between Stages 0 and III (p < 0.001). Disruption of the blood-brain barrier as indicated by extravasation of Evans blue dye correlated well with the pressure increment. These results may indicate the threshold for injury after cortical venous occlusion. Venous stump pressure measurements obtained during a test occlusion may be a useful adjunct in predicting brain damage and may be helpful for intraoperative vessel selection for venous resection.

Coagulopathy in pediatric abusive head trauma.

Coagulopathy is a potential complication of head trauma that may be attributable to parenchymal brain damage. The objectives of this study were to assess the frequency of coagulation defects in pediatric abusive head trauma and to analyze their relationship to parenchymal brain damage. We reviewed the records of 265 pediatric patients hospitalized for head trauma. One hundred forty-seven patients met study inclusion criteria: (1) radiologic evidence of head trauma, (2) multidisciplinary validation that head trauma had been inflicted, and (3) coagulation screening performed within 2 days of presentation. Using nonparametric analysis, initial coagulation test results were compared between study patients without parenchymal brain damage and those with parenchymal brain damage. Mild prothrombin time (PT) prolongations (median 13.1) occurred in 54% of study patients with parenchymal brain damage and only 20% of study patients without parenchymal brain damage. Among pediatric abusive head trauma patients with parenchymal brain damage who died, 94% displayed PT prolongations (median 16.3) and 63% manifested evidence of activated coagulation. PT prolongation and activated coagulation are common complications of pediatric abusive head trauma. In the presence of parenchymal brain damage, it is highly unlikely that these coagulation abnormalities reflect a preexisting hemorrhagic diathesis. These conclusions have diagnostic, prognostic, and legal significance.

Computerized tomography and prognosis in paediatric head injury.

The authors have analysed the computerized tomography (CT) findings and their correlation with the clinical state, early and late outcome in children and adolescents with head injuries (HI). This study represents clinical and CT data of 82 consecutive HI patients under 18 years of age. Among them 51 (62%) were boys and 31 (38%) girls. The application of CT to the evaluation of the morphologic manifestations of HI in children has shown some differences in forms and mechanisms of injury and in outcome compared to adults. In the paediatric HI the most frequent finding was diffuse brain swelling with CT evidence of ventricular and cisternal compression or obliteration. Prognostically the most unfavourable findings were shearing injury, intracerebral and subdural haematomas combined with brain swelling and parenchymal damage. According to the Lidcombe impairment scale, outcome from severe paediatric HI was determined in the 3rd and 6th months, one year and 2 years after the injury. The outcome two years after severe HI varied to a great extent and was better in children than in adults. Although there was long-term disruption of the patient's quality of life, our data show that as there are no predictors of individual outcomes in child HI, no child should be excluded from early and long-term rehabilitation.

Improving cancer radiotherapy with 2-deoxy- d-glucose: phase I/II clinical trials on human cerebral gliomas

Purpose : Evaluation of tolerance, toxicity, and feasibility of combining large fraction (5 Gy) radiotherapy with 2-deoxy- d-glucose (2DG), an inhibitor of glucose transport and glycolysis, which has been shown to differentially inhibit repair of radiation damage in cancer cells. Methods and Materials : Twenty patients with supratentorial glioma (Grade 3 4 ), following surgery were treated with four weekly fractions of oral 2DG (200 mg/kg body weight) followed by whole brain irradiation (5 Gy). Two weeks later, supplement focal radiation to the tumor site (14 Gy/7 fractions) was given. Routine clinical evaluation, x-ray computerized tomography (CT), and magnetic resonance (MR) imaging were carried out to study the acute and late radiation effects. Results : All the 20 patients completed the treatment without any interruption. The vital parameters were within normal limits during the treatment. None reported headache during the treatment. Mild to moderate nausea and vomiting were observed during the days of combined therapy (2DG + RT) in 10 patients. No significant deterioration of the neurological status was observed during the treatment period. Seven patients were alive at 63, 43, 36, 28, 27, 19, and 18 months of follow-up. In these patients, the clinical and MR imaging studies did not reveal any late radiation effects. Conclusions : Feasibility of administering the treatment (2DG + 5 Gy) is demonstrated by the excellent tolerance observed in all 20 patients. Further, the clinical and MR studies also show the absence of any brain parenchymal damage.

Multiple brain abscesses from isolated cerebral mucormycosis.

A report is presented of a patient with cerebral mucormycosis without rhinosinusal or systemic evidence of the disease. The predisposing condition was drug-induced immunosuppression. Computed tomography (CT) showed focal areas of abnormal enhancement which correlated with necropsy findings of localised parenchymal brain damage; this represented encapsulated brain abscesses, a rare form of presentation of cerebral mucormycosis.

Early collateral blood supply and late parenchymal brain damage in patients with middle cerebral artery occlusion.

We angiographically studied 80 patients within 6 hours after the onset of ischemic supratentorial infarction. From this group we selected 36 patients with middle cerebral artery occlusion who survived. In these 36 patients, we compared the presence of a collateral blood supply during the early phase with the extent of final parenchymal brain damage obtained by computed tomography 3 months after the event. The presence of a collateral circulation during the first few hours after the stroke reduced the size of the final parenchymal brain damage in patients with middle cerebral artery stem-trunk occlusion. The collateral blood supply was more efficient in patients who had no significant stenosing lesions of the extracranial internal carotid artery. Our data confirm that the lenticulostriate arteries are end arteries not supplied by collateral blood vessels and suggest that lesions formerly thought to be caused by hemodynamic mechanisms (watershed infarcts) or arteriolar lesions (lacunar infarcts) may be due to middle cerebral artery occlusions.

Multinucleated giant cells in brain: a hallmark of the acquired immune deficiency syndrome (AIDS).

Multinucleated giant cells (MGCs) were found in the brains of two patients with the acquired immune deficiency syndrome (AIDS), but were absent in five other AIDS brains. In one case there was a distinctive distribution of MGCs in disseminated clusters; damage of brain parenchyma was minor or absent. In another case, MGCs were restricted largely to the perivascular spaces and were accompanied by lesions of toxoplasmosis and cytomegalovirus infection. In paraffin sections, morphological and histochemical-staining characteristics of MGCs were similar to those of macrophages. Occasional immuno-labeling of MGCs with monoclonal antibody to leukocyte common antigen suggested a hematogenous origin. MGCs were not stained by immunocytochemistry for neural markers glial fibrillary acidic protein, S 100 protein, neurofilament proteins, neuron specific enolase, and myelin basic protein and, therefore, appear unlikely to originate from the neuroepithelium. In the absence of evidence of other infections in case 1, the peculiar tissue reaction found could be a direct result of infection by the AIDS retrovirus. The formation of MGCs is likely to represent a cytopathic effect of the virus on lymphoid or monohistiocytic cells infiltrating the brain (infection of these cells could occur before or after they entered the brain). These assumptions are supported by the finding of similar MGCs in permissive lymphoid cell cultures after infection with the AIDS retrovirus.

Predictive value of serum lactate dehydrogenase in head injury.

Serum total lactate dehydrogenase (LDH) was estimated serially for up to 15 days in 110 patients with head injuries who had no extraneural injury. Increase in LDH activity generally indicated the degree of parenchymal brain damage. The prognostic value of LDH was established by correlating its activity with clinical criteria such as duration of unconsciousness and post-traumatic amnesia, type of brain damage, and quality of survival. A significant rise in LDH activity suggested severe brain damage and poor prognosis.

Intracranial injections of 6-OHDA. Comparison of catecholamine-depleting effects of different volumes and concentrations

Fluorescence histochemistry was used to assess monoamine depletion after injections of 6-OHDA into selected brain areas. Two volumes (2 and 4 μl) and 4 concentrations (1, 2, 4 and 8 μg/μl) of 6-OHDA were injected into the olfactory tubercle, the posterior lateral hypothalamus and the lateral hypothalamus. Selective destruction of catecholamine-containing neurons resulted from all injections of 6-OHDA with the exception of the 2 lowest doses (2 and 4 μl of 1 μg/μl) and the highest dose (4 μl of 8 μg/μl) which produced nonspecific damage of brain parenchyma. The results indicate that, in addition to the selection of an effective dose, it is also possible to choose a site of injection which will produce a maximal area of specific depletion. In cases where injections into terminal areas caused limited specific depletion the same dose injected into preterminal axons often caused a more widespread loss of flourescence. With volume, concentration and anatomical location being important variables to consider, caution is needed in the interpretation of behavioural experiments. When using 6-OHDA it is necessary to show that specific depletion of catecholamines has been achieved.

Lactic dehydrogenase isoenzymes following head injury

Serial levels of lactic dehydrogenase (LDH) isoenzymes have been measured in 92 neurosurgical patients with damaged brains, including 77 suffering from head injury. Serum LDH isoenzymes 1 and 2 rise in the injured group and generally reflect the degree of parenchymal brain damage. The method has possible diagnostic applications, as well as some prognostic use.