bluuebunny/crossref_metadata_2025_split huggingface dataset:
The kallikrein-kinin system as mediator in vasogenic brain edema
Authors: Maier-Hauff Klaus , Baethmann Alexander J. , Lange Manfred , Schürer Ludwig , Unterberg Andreas 
Published: May 2009

✓ Vasogenic edema was induced in mongrel cats by cold injury to study uptake and activation of the plasma-kallikrein-kinin system in central nervous system (CNS) tissue. A method was developed for quantitative assessment of kinin formation in affected brain tissue areas. Gross disruption of the blood-brain barrier by focal trauma causes marked penetration of plasma kininogens into necrotic and edematous brain tissue. Moreover, the kallikrein-kinin (KK) system was activated in both necrotic and perifocal edematous areas, and was markedly enhanced by additional cerebral ischemia. Formation of kinins in necrotic brain tissue led to consumption of approximately 60% to 80% of the amount of kininogens being taken up. In perifocal edematous tissue, formation of kinins was less pronounced, or even absent. However, if cerebral ischemia evolved after severe intracranial hypertension, kinins were also formed in the perifocal edematous brain. The intravascular origin of kininogens found in pathological tissue areas secondary to injury was deduced from the observation that cerebral tissue of the contralateral hemisphere with an intact blood-brain barrier had no measurable quantities of kininogens. Consumption of plasma kininogens or formation of kinins were assessed as the difference of the total amount of plasma kininogens taken up into the tissue minus the amount of kininogens found in the brain at postmortem examination.
The data indicate that uptake and activation of the plasma-KK system might occur under all pathological conditions in which blood-brain barrier damage permits cerebral penetration of plasma proteins, such as with cerebral contusion, focal ischemia, and tumors. The potent pathophysiological mechanisms induced by kinins in CNS tissue, such as formation of brain edema, microcirculatory dysfunction, and enhancement of blood-brain barrier permeability, together with their formation in focal and perifocal pathological brain tissue, provide further support for a mediator function of the KK system. Methods that specifically interfere with the formation of kinins in damaged brain should therefore be expected to attenuate vasogenic edema.
Anterior cord decompression and spinal stabilization for patients with metastatic lesions of the spine
Authors: Harrington Kevin D. 
Published: May 2009

✓ Metastatic lesions involving the spine may cause vertebral body collapse, resulting in either spinal instability or neural compression, or both. Progressive destruction of the vertebral body by the tumor may cause increasing spinal instability, leading to a kyphotic deformity and further neural deficit. Anterior decompression allows direct excision of the tumor focus and direct neural decompression. Because of postoperative irradiation, conventional bone grafts are rarely incorporated.
Over an 8-year period, 52 patients with spinal instability secondary to metastatic pathological fractures of one or more vertebrae underwent anterior decompression and stabilization by replacement of the affected vertebral bodies with methyl methacrylate, polymerizing in situ. No postoperative external support was required, and the acrylic fixation achieved by this method was not affected adversely by subsequent irradiation to a mean of 4020 rads. Forty patients had major neurological impairment preoperatively and required anterior spinal cord and/or nerve root decompression prior to fixation. Of these, 21 had complete neurological recovery postoperatively, 13 others were improved significantly, five remain unchanged, and one patient deteriorated neurologically. There were three cases with failure of fixation. Seven other patients did not benefit from the procedure because of specific complications or the advanced state of their disease. The remaining 42 patients had good relief of pain and restoration of spinal stability, which did not deteriorate during the follow-up period, ranging from 6 to 100 months postoperatively.
Effects of a single large dose of methylprednisolone sodium succinate on experimental posttraumatic spinal cord ischemia
Authors: Hall Edward D. , Wolf Daniel L. , Braughler J. Mark 
Published: May 2009

✓ The ability of a single large intravenous dose of methylprednisolone sodium succinate (MPSS: 15, 30, or 60 mg/kg) to modify the evolution of lumbar spinal cord ischemia in cats undergoing a contusion injury of 500 gm-cm is examined. Repeated measurements of spinal cord blood flow (SCBF) in the dorsolateral funiculus were made via the hydrogen clearance technique before and for 4 to 5 hours after injury. The mean preinjury SCBF for all animals was 12.29 ± 0.77 ml/100 gm/min. Following injury, SCBF began to decrease progressively in vehicle-treated animals to a level of 7.71 ml/100 gm/min, a fall of 37.3%. In contrast, cats that received a 30-mg/kg intravenous dose of MPSS at 30 minutes after injury maintained SCBF within normal limits (p < 0.05 at 3 and 4 hours after contusion). A 15-mg/kg MPSS dose was less effective at preventing posttraumatic white matter ischemia, and a 60-mg/kg dose was essentially ineffective.
It was determined that the 30-mg/kg MPSS dose was optimal for supporting SCBF when the drug was given at 30 minutes after spinal trauma, and a second series of experiments was carried out to examine the ability of this dose, when given at longer latencies, to improve decreased flow. Methylprednisolone given at 1½ hours after injury in four cats produced a slight (12.7%) but transient improvement in SCBF, and when administered at 4½ hours in another three animals was totally ineffective. These results show that MPSS in a 30-mg/kg dose can prevent posttraumatic spinal cord ischemia. However, it would appear that the ability of the steroid to reverse the ischemia once it has developed is limited, and probably lost, within a few hours of onset. This further suggests that the ischemic process is irreversible and underscores the need for early treatment with a large MPSS dose in order to prevent full development of ischemia and to promote neurological recovery.
Cerebral blood flow and metabolism in comatose patients with acute head injury
Authors: Obrist Walter D. , Langfitt Thomas W. , Jaggi Jurg L. , Cruz Julio , Gennarelli Thomas A. 
Published: May 2009

✓ Cerebral blood flow (CBF) measurements were made in 75 adult patients with closed head injuries (mean Glasgow Coma Scale score 6.2), using the xenon-133 intravenous injection method with eight detectors over each hemisphere. All patients were studied acutely within 96 hours of trauma, and repeatedly observed until death or recovery (total of 361 examinations). Arteriojugular venous oxygen differences (AVDO2) were obtained in 55 of the patients, which permitted assessment of the balance between metabolism and blood flow, and provided estimates of cerebral metabolic rate for oxygen (CMRO2).
Based on mean regional CBF, the patients were classified into two groups: those who exhibited hyperemia on one or more examinations, and those who had a consistently reduced flow during their acute illness. “Hyperemia” was defined as a normal or supernormal CBF in the presence of coma, a definition that was independently confirmed by narrow AVDO2's indicative of “luxury perfusion.” During coma, all patients showed a significant depression in CMRO2.
Forty-one patients (55%) developed an acute hyperemia with an average duration of 3 days, while 34 patients (45%) consistently had subnormal flows. Although more prevalent in younger patients, hyperemia was found at all age levels (15 to 85 years). There was a highly significant association between hyperemia and the occurrence of intracranial hypertension, defined as an intracranial pressure above 20 mm Hg. Patients with reduced flow showed little or no evidence of global cerebral ischemia, but instead revealed the expected coupling of CBF and metabolism. The CBF responses to hyperventilation were generally preserved, with the hyperemic patients being slightly more reactive. In 10 patients with reduced flow, hyperventilation resulted in wide AVDO2's suggestive of ischemia.
Morphological changes of the basilar artery, ventricles, and choroid plexus after experimental SAH
Authors: Liszczak Theodore M. , Black Peter McL. , Tzouras Argyris , Foley Lorraine , Zervas Nicholas T. 
Published: May 2009

✓ Experimental subarachnoid hemorrhage (SAH) was induced in adult rabbits by three repeated cisterna magna injections of autologous nonheparinized blood. One week after the last blood injection the animals were sacrificed and examined for morphological change.
No vasculopathy was noted in the basilar arteries and no periarterial thrombus was seen around the majority of these arteries. Gross and microscopic changes were observed in both the ventricles and choroid plexus. Ventricular changes included dilation of the lateral ventricles, destruction of ciliated ependymal cells, and deposition of small amounts of blood throughout the ventricular system. These ventricular changes are similar to the pathological sequelae of SAH in patients. Choroid plexus changes included electron-dense cytoplasmic inclusions and dilation of the lateral and subcellular spaces. The ventricular surface and the choroid plexus are both affected by the intracisternal injection of blood. The hydrocephalus that follows SAH may be potentiated by ependymal disruption and loss of ciliated activity in the ventricles. Changes in choroid plexus function may also occur.
Cerebral hemodynamics in normal-pressure hydrocephalus
Authors: Tamaki Norihiko , Kusunoki Tadaki , Wakabayashi Toshimitsu , Matsumoto Satoshi 
Published: May 2009

✓ Cerebral hemodynamics in 31 patients with suspected normal-pressure hydrocephalus were studied by means of the xenon-133 (133Xe) inhalation method and on dynamic computerized tomography (CT) scanning. Cerebral blood flow (CBF) is reduced in all patients with dementia. Hypoperfusion was noted in a frontal distribution in these patients compared with normal individuals. There was no difference in CBF patterns between patients with good and those with poor outcome. The CBF was increased following cerebrospinal fluid (CSF) shunting in patients who responded to that procedure: increase in flow correlated with clinical improvement, frontal and temporal lobe CBF was most markedly increased, and the CBF pattern became normal. In contrast, CBF was decreased after shunt placement in patients who were considered to have suffered from degenerative dementia, as evidenced by non-response to shunting.
Dynamic computerized tomography studies demonstrated that patients with a good outcome showed a postoperative reduction in mean transit time of contrast material, most prominent in the frontal and temporal gray matter, and slight in the deep frontal structures, but not in the major cerebral vessels. Patients with poor outcome after shunting, however, had an increase in transit time in all regions. This corresponded well with the results as determined by the 133Xe inhalation method.
Medulloblastoma in childhood: an epidemiological study
Authors: Farwell Jacqueline R. , Dohrmann George J. , Flannery John T. 
Published: May 2009

✓ The authors have reviewed 143 cases of medulloblastoma in children aged 19 years or younger who were treated in a 42-year period and reported in the Connecticut Tumor Registry. About 20 cases have occurred in each 5-year period since 1950, but 31 were seen between 1955 and 1959. Correspondingly, an excessive number of children born in the period 1954 to 1958 have developed medulloblastomas. A relationship to polio vaccine contaminated with SV40 virus may exist. Children with medulloblastomas had an increased number of immediate family members with brain tumors, leukemia, and childhood cancer when compared to controls. In this series, the male to female ratio was 1.33:1. Average age at diagnosis was 6½ years, with most children being diagnosed at 3 years old and fewer cases appearing in each successive hemidecade from birth to 20 years of age.
Probability of survival at 6 months was 0.687; at 1 year, 0.444; at 2 years, 0.314; and at 5 years, 0.222. Survival probability was statistically significantly better in the years 1968 to 1977 than in previous decades, in part due to fewer autopsy diagnoses and lowered operative mortality, but also due to a decreased mortality rate in children several years after diagnosis. Fifty-one percent were treated with operation and irradiation, 17% with operation alone, 12% with irradiation alone, and 5% with operation, irradiation, and chemotherapy. Fifteen percent were not treated. One- and 5-year survival rates in patients with operation and irradiation were, respectively, 0.615 and 0.307; with operation, 0.125 and 0.042; with irradiation, 0.688 and 0.277; and with operation, irradiation, and chemotherapy, 0.857 and 0.643. All seven children who received chemotherapy were diagnosed after 1968, and five are still alive. Perhaps due to short follow-up time, the course and mortality rate of children treated with all three modalities were not statistically significantly different from those of children treated since 1968 with operation and radiation therapy.
Neurosurgical management of low-grade astrocytoma of the cerebral hemispheres
Authors: Laws Edward R. , Taylor William F. , Clifton Marvin B. , Okazaki Haruo 
Published: May 2009

✓ The authors conducted a retrospective review of surgically treated, histologically proven cases of low-grade (Grade 1 or 2) astrocytomas. Follow-up analysis, with survival time as the end-point, was completed using multivariant statistical analysis. In the 461 cases of supratentorial low-grade astrocytoma in this study, age of the patient at the time of surgery was by far the most important variable in predicting length of survival. Other variables correlating with increasing survival times were: gross total surgical removal, lack of major preoperative neurological deficit, long duration of symptoms prior to surgery, seizures as a presenting symptom, lack of major postoperative neurological deficit, and surgery performed in recent decades. The multi-variant regression analysis showed that radiation therapy was of clear benefit, primarily in older patients with incompletely removed tumors.
For purposes of establishing prognosis and testing the results, a “score” was developed to predict survival times, based on the most important variables. The data in this study provide a basis for the analysis of future modes of management of low-grade gliomas.
Use of intraoperative auditory evoked potentials to preserve hearing in unilateral acoustic neuroma removal
Authors: Ojemann Robert G. , Levine Robert A. , Montgomery William M. , McGaffigan Patricia 
Published: May 2009

✓ Twenty-two patients with unilateral acoustic neuromas and preoperative speech discrimination scores of 35% or more had intraoperative monitoring of the electrocochleogram (ECoG) using a transtympanic electrode, and of the brain-stem auditory evoked potentials (BAEP's) using scalp electrodes. Rapid feedback was provided about the status of the cochlear microphonics from the hair cells of the inner ear (CM of the ECoG), the compound action potential of the auditory nerve (N-1 of the ECoG or Wave I of the BAEP's) and the potentials from the lower brain stem (Wave V of the BAEP's). All patients had total removal of the tumor. In 21, the cochlear nerve was anatomically preserved, and 20 had good postoperative facial nerve function. Correlation of tumor size with postoperative hearing was as follows: discrimination scores of more than 35% in three of four patients with 1-cm tumors, two of eight with 1.5-cm tumors, two of six with 2- to 2.5-cm tumors, and one of four with tumors of 3 cm or more. Two other patients with 1.5-cm tumors had discrimination scores of less than 35%, and one patient with a 2-cm tumor had only sound perception. In two patients, the discrimination scores improved. At the end of the operation, all patients with hearing had a detectable N-1, and, when recorded, CM. All but one patient with no hearing had lost N-1, and CM was absent or reduced. Unless Wave V was unchanged, it was a poor predictor of postoperative hearing, and its absence did not preclude preservation of good hearing.
The electrophysiological changes during each stage of the operation were analyzed and correlated with events during surgery. Areas in which there was an increased risk of loss of the potentials were determined. In some patients monitoring was unnecessary, because either there were no significant changes or the changes were abrupt and no recovery occurred. However, in other patients, monitoring alerted the surgeon to a possible problem and the method of dissection was altered. Possible mechanisms of hearing loss were suggested from the changes in the recordings.
Saccular aneurysm associated with segmental duplication of the basilar artery
Authors: Black Samuel P. W. , Ansbacher Linda E. 
Published: May 2009

✓ Saccular aneurysm associated with segmental duplication (also called “fenestration”) of the basilar artery is an anomaly that results from an embryonic fault. Reports of the treatment of the aneurysmal component have only recently appeared in the neurosurgical literature, and little has been written on the morphology of this anomaly. This study answers the need for information about its structure to the extent permitted by the examination of a single specimen.
The specimen was obtained at postmortem examination. A cast of its interior features was made with a synthetic rubber. After the cast was removed, the entire anomaly was serially sectioned for histological study. Defects in the wall of the basilar artery were seen microscopically at each end of the fenestration. At the extensive proximal defect, a saccular aneurysm arose that bulged into the window between the two limbs of the segmental duplication and also presented dorsally and ventrally. It had fatally ruptured. The manner in which the fenestration was formed by intraluminal septa was also revealed.
Role of surgery in hypertensive intracerebral hematoma
Authors: Kanno Tetsuo , Sano Hirotoshi , Shinomiya Youichi , Katada Kazuhiro , Nagata Junji , Hoshino Masaaki , Mitsuyama Fuyuki 
Published: May 2009

✓ The indications for surgery in hypertensive intracerebral hematoma are still controversial. The reason for this may be: 1) lack of adequate and comparable data in conservative and surgical therapy from the same institution; 2) lack of adequate close follow-up monitoring over an extended period of time; or 3) lack of proper classification of hematomas for comparison of results from different institutions. The authors have treated 459 cases of hypertensive intracerebral hematoma between October, 1975, and July, 1983. The hematomas have been classified according to their mode of extension on computerized tomography. The long-term outcome was assessed on the basis of activity of daily living.
Putaminal hematomas were classified as mild, moderate, severe, and very severe. In general, there was no significant difference in outcome between the surgical and nonsurgical cases; however, the outcome in the moderate and severe hematomas was found to be a little better for the surgical cases in some restricted areas. Thalamic and pontine hemorrhages were classified as mild, moderate, or severe. If the hematoma is localized to the thalamus or pons, and if it extends to the midbrain, there is no indication for surgery; however, in patients with moderate hematomas, the prognosis showed a variable outcome, and the indications for surgery were questionable. In cerebellar hematomas, the authors propose that even a hematoma with a diameter greater than 3 cm might show a good outcome with nonsurgical therapy.
Distribution of hematoporphyrin derivative in the rat 9L gliosarcoma brain tumor analyzed by digital video fluorescence microscopy
Authors: Boggan James E. , Walter Robert , Edwards Michael S. B. , Borcich Janis K. , Davis Richard L. , Koonce Michael , Berns Michael W. 
Published: May 2009

✓ A digital video fluorescence microscopy technique was used to evaluate the distribution of hematoporphyrin derivative (HPD) in the rat intracerebral 9L gliosarcoma brain-tumor model at 4, 24, 48, and 72 hours after intravenous administration of 10 mg/kg of the drug. Compared to surrounding normal brain, there was significant preferential uptake of HPD into the tumor. In sections surveyed, fluorescence reached a maximum value by 24 hours; however, only 33% to 44% of the tumor was fluorescent. In contrast, fluorescence within the surrounding normal brain was maximum at 4 hours, but was present in less than 1% of the brain tissue evaluated.
The effect of HPD sensitization to a laser light dose (633 nm) of 30 joules/sq cm delivered through the intact skull was evaluated histologically in 10 rats. A patchy coagulation necrosis, possibly corresponding to the distribution of HPD fluorescence seen within the tumor, was observed. There was evidence that photoradiation therapy (PRT) affects defective tumor vasculature and that a direct tumor cell toxicity spared normal brain tissue. Despite these findings, limited uptake of HPD in tumor and the brain adjacent to tumor may decrease the effectiveness of PRT in the 9L gliosarcoma brain-tumor model. Because of the similarity between the capillary system of the 9L tumor and human brain tumors, PRT may have a limited therapeutic effect in patients with malignant brain tumors.
Meningioma: analysis of recurrence and progression following neurosurgical resection
Authors: Mirimanoff René O. , Dosoretz Daniel E. , Linggood Rita M. , Ojemann Robert G. , Martuza Robert L. 
Published: May 2009

✓ The rates of survival, tumor recurrence, and tumor progression were analyzed in 225 patients with meningioma who underwent surgery as the only treatment modality between 1962 and 1980. Patients were considered to have a recurrence if their studies verified a mass effect in spite of a complete surgical removal, whereas they were defined as having progression if, after a subtotal excision, there was clear radiological documentation of an increase in the size of their tumor. There were 168 females and 57 males (a ratio of 2.9:1), with a peak incidence of tumor occurrence in the fifth (23%), sixth (29%), and seventh (23%) decades of life. Anatomical locations were the convexity (21%), parasagittal area (17%), sphenoid ridge (16%), posterior fossa (14%), parasellar region (12%), olfactory groove (10%), spine (8%), and orbit (2%). The absolute 5-, 10-, and 15-year survival rates were 83%, 77%, and 69%, respectively.
Following a total resection, the recurrence-free rate at 5, 10, and 15 years was 93%, 80%, and 68%, respectively, at all sites. In contrast, after a subtotal resection, the progression-free rate was only 63%, 45%, and 9% during the same period (p < 0.0001). The probability of having a second operation following a total excision after 5, 10, and 15 years was 6%, 15%, and 20%, whereas after a subtotal excision the probability was 25%, 44%, and 84%, respectively (p < 0.0001). Tumor sites associated with a high percentage of total excisions had a low recurrence/progression rate. For example, 96% of convexity meningiomas were removed in toto, and the recurrence/progression rate at 5 years was only 3%. Parasellar meningiomas, with a 57% total excision rate, had a 5-year probability of recurrence/progression of 19%. Only 28% of sphenoid ridge meningiomas were totally resected, and at 5 years the probability of recurrence/progression was 34%. In patients undergoing a second resection, the probability of a third operation at 5 and 10 years was 42% and 56%, respectively. There was no difference in the recurrence/progression rates according to the patients' age or sex, or the duration of symptoms. Implications for the potential role of adjunctive medical therapy or radiation therapy for meningiomas are discussed.