bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cognition following subarachnoid hemorrhage from anterior communicating artery aneurysm: relation to timing of surgery
Authors: Mavaddat Nahal , Sahakian Barbara J. , Hutchinson Peter J. A. , Kirkpatrick Peter J. 
Published: May 2009

Object. This study was conducted to define neuropsychological changes following operation for subarachnoid hemorrhage (SAH) caused by rupture of an anterior communicating artery (ACoA) aneurysm and to assess the influence of the timing of surgery to clip the aneurysm.Methods. Cognitive outcome was evaluated using the Cambridge Neuropsychological Test Automated Battery in patients with an ACoA aneurysm that had caused an SAH. Adult patients younger than 70 years of age who had achieved a favorable neurological outcome (Glasgow Outcome Scale scores of 4 or 5) were studied 6 to 24 months postsurgery. Patients were divided into early (Days 0–3) and late surgery groups (after Day 3) according to the timing of surgery after the ictus. Neuropsychological analysis was performed by reviewers who were blinded to the timing of surgery.Forty-seven patients whose mean age was 51.5 years were tested. They were compared with age- and intelligence quotient (IQ)—matched controls by using premorbid IQ as estimated on the National Adult Reading Test. Patients showed deficiencies in several tasks of verbal fluency, pattern recognition, and spatial working memory; this profile of deficits was similar to that seen in patients who underwent temporal lobe excisions. However, there was no significant difference in cognitive performance between the early and late surgery groups.Conclusions. After open surgery for ruptured ACoA aneurysms, patients who have achieved a favorable neurological outcome still exhibit significant cognitive deficits, primarily in tests sensitive to temporal lobe dysfunction. However, early surgery does not carry a higher risk of neuropsychological disability.
Percutaneous transluminal angioplasty for intracranial atherosclerotic lesions: evolution of technique and short-term results
Authors: Connors J. J. , Wojak Joan C. 
Published: May 2009

Object. A retrospective analysis of a 9-year experience with balloon angioplasty for intracranial atherosclerotic stenosis was undertaken with the goals of illustrating development of a safe technique for treatment of intracranial atherosclerotic disease and reporting the immediate results in this series of patients.Methods. Three distinct periods are defined, based on the technique used. In the early period, in which eight patients were treated, the angioplasty balloon size approximated the vessel size, but was always smaller. Angioplasty was moderately rapid and brief (15–30 seconds). Clinical improvement occurred in seven (87.5%) of eight patients, dissection without consequence occurred in four (50%) of eight, and residual stenosis greater than 50% was found in three (37.5%) of eight. No neurological complications occurred.In the middle period, in which 12 patients were treated, the balloon size approximated the vessel size, but oversizing by up to 0.25 mm was permitted. Angioplasty was extremely rapid and brief. Angiographically visible dissection occurred in nine (75%) of 12 patients, necessitating urokinase infusion in five (41.7%) of 12 and producing abrupt occlusion in one (8.3%) of 12, resulting in death. Occlusion secondary to the recrossing of the lesion occurred in one (8.3%) of 12, resulting in stroke. Good outcome was eventually achieved in 10 (83.3%) of 12.In the current period, in which 50 patients have been treated, the balloon is always undersized and inflation is extremely slow (several minutes). Dissection occurred in seven (14%) of 50 patients, necessitating fibrinolysis in two of 50 (4%, both uneventful) and producing no abrupt occlusion or stroke. Residual stenosis greater than 50% occurred in eight (16%) of 50, with no stenosis greater than 70%. Late restenosis occurred in four (9%) of 44 and successful repeated angioplasty was performed in all four. One guidewire vessel perforation occurred (2%), resulting in the patient's death. Good angiographic and short-term clinical outcome was achieved in the other 49 patients (98%).Conclusions. Extremely slow balloon inflation combined with balloon undersizing results in decreased intimal damage, decreased acute platelet/thrombus deposition, and decreased acute closure. This technique sometimes yields suboptimal angiographic results but achieves the clinical goal safely. Intracranial angioplasty can be safely performed using this technique and modern equipment.
Oxyhemoglobin-induced apoptosis in cultured endothelial cells
Authors: Ogihara Kotaro , Zubkov Alexander Y. , Bernanke David H. , Lewis Adam I. , Parent Andrew D. , Zhang John H. 
Published: May 2009

Object. Oxyhemoglobin (OxyHb) is one of the most important spasmogens for cerebral vasospasm that follows aneurysmal subarachnoid hemorrhage. The cytotoxic effect of OxyHb has been documented in endothelial and smooth-muscle cells; however, the pattern of cell death—necrosis or apoptosis—as the final stage of cell damage has not been demonstrated. This study was undertaken to determine if OxyHb induces apoptotic changes in cultured bovine aortic endothelial cells.Methods. Confluent bovine aortic endothelial cells were treated with OxyHb in a concentration- and time-dependent manner. Cell density was assayed by counting the number of cells that attached to culture dishes after exposure to OxyHb. To identify apoptotic changes, the investigators used three specific methods: DNA fragmentation (electrophoreses), the apoptotic body (transmission electron microscopy), and cleavage of poly (adenosine diphosphate ribose) polymerase (PARP [Western blotting]).Conclusions. Oxyhemoglobin decreased cell density in a concentration- and time-dependent manner. Analysis of DNA showed a pattern of internucleosomal cleavage characteristic of apoptosis (DNA ladder). Transmission electron microscopy demonstrated condensation of nuclei and apoptotic bodies in OxyHb-treated endothelial cells. Western blotting with the PARP antibody revealed that the 116-kD PARP was cleaved to the 85-kD apoptosis-related fragment. These results for the first time demonstrated that the OxyHb induces apoptosis in cultured endothelial cells.
Topographic anatomy of the cochlear nuclear region at the floor of the fourth ventricle in humans
Authors: Quester Ralf , Schröder Roland 
Published: May 2009

Object. The development of appropriate methods to stimulate the dorsal and ventral cochlear nucleus by means of an auditory brainstem implant in patients with acquired bilateral anacusis requires a detailed topoanatomical knowledge both of the location and extension of the nuclear surface in the fourth ventricle and lateral recess and of its variability. The goal of this study was to provide that information. Anatomically, it is possible to use a midline surgical approach to the fourth ventricle rather than the translabyrinthine and suboccipital routes of access used hitherto. This is especially useful if severe scarring, which occurs as a result of tumor removal in the cerebellopontine angle, make the orientation and placement of an auditory brainstem implant via a lateral surgical approach difficult. There have been only a few studies, involving single cases and small series of patients, in which the focus was the exact extension of the cochlear nuclei, whose microsurgically relevant position in relation to the surface structures is not known in detail.Methods. Landmarks that are important for the placement of an auditory brainstem implant through the fourth ventricle were examined and measured in a large series of 28 formalin-fixed human brainstems. In all cases, these examinations were supplemented by addition of a histological section series. For the first time values of unfixed fresh brainstem tissue were determined. Anatomical features are discussed with regard to their possible neurosurgical relevance, taking into account inter- and intraindividual variability.Conclusions. The midline approach would provide an opportunity to stimulate the whole area of the dorsal as well as the ventral cochlear nucleus with an auditory brainstem implant.
Immunohistochemical staining of DNA topoisomerase IIα in human gliomas
Authors: Taniguchi Katsumi , Wakabayashi Toshihiko , Yoshida Tazuka , Mizuno Masaaki , Yoshikawa Kazuhiro , Kikuchi Akihiko , Nakashima Nobuo , Yoshida Jun 
Published: May 2009

Object. The enzyme DNA topoisomerase IIα (Topo IIα) was tested as a measure of cell proliferation in gliomas.Methods. Immunostaining for the Topo IIα and for the Ki-67 antigen (MIB-1 antibody) was performed in paraffin-embedded tissue sections obtained from 25 resected human gliomas. Additionally, cultured human glioma cells were subjected to simultaneous flow cytometry to determine Topo IIα and DNA content.Using flow cytometric analysis, the authors found that the Topo IIα antibody labeled cells in the S, G2, and M phases of the cell cycle and also those in some parts of the G0 and G1 phases. In histological sections, Topo IIα showed more distinct staining than MIB-1, particularly in older archival cases. The proliferative indices (PIs) based on cells staining for MIB-1 and Topo IIα correlated highly with one another (r = 0.96). The Topo IIα PI immunopositivity was seen in 4.07% of cells in the low-grade astrocytoma group, 11.97% in the anaplastic astrocytoma group, and 13.84% in the glioblastoma multiforme group, representing significant differences between low-grade astrocytoma and both anaplastic astrocytoma and glioblastoma. A Topo IIα PI less than 5% predicted longer patient survival (p = 0.003).Conclusions. Immunostaining for Topo IIα represents a useful alternative to MIB-1 as a proliferative index in human gliomas.
Extracranial vertebral artery stent placement: in-hospital and follow-up results
Authors: Chastain Hollace D. , Campbell Morgan S. , Iyer Sriram , Roubin Gary S. , Vitek Jiri , Mathur Atul , Al-Mubarak Nadim A. , Terry John B. , Yates Virginia , Kretzer Kimberly , Alred Diane , Gomez Camilo R. 
Published: May 2009

Object. The authors summarize their experience with stent deployment in the treatment of vertebrobasilar artery (VBA) insufficiency. This is an underdiagnosed condition, and the incidence of significant vertebral artery (VA) stenosis has been underappreciated. Medical therapy has been the mainstay of treatment because of the high rate of morbidity associated with surgical correction of VA stenosis. Recently, some authors have reported acceptable results with the use of percutaneous transluminal angioplasty, but this technique has significant weaknesses such as elastic recoil and problems in achieving safe treatment of dissections.Methods. The authors investigated the feasibility, safety, and outcome of VA stent placement in 50 patients in whom 55 vessels were treated using stents. Technical success was achieved in 54 (98%) of 55 vessels, with no procedure-related complications. However, one patient (2%) died of nonneurological causes, and one (2%) suffered a stroke that occurred within the 30-day postprocedural period and was related to a complicated coronary intervention. Clinical follow-up review performed at a mean of 25 ± 10 months revealed two patients (4%) with recurrence of VBA symptoms. Six-month angiographic follow up was completed in 90% of eligible patients, with a 10% incidence of restenosis as defined by greater than 50% luminal narrowing.Conclusions. Vertebral artery stent placement is feasible in patients who have significant VA stenosis, with predictably good angiographically demonstrated and clinical results. The 6-month angiographically confirmed restenosis rate appears to be low, as does the clinical recurrence rate. This technique solves the problems of elastic recoil and the treatment of angioplasty-induced dissections. Further prospective comparison with medical preventive strategies is warranted.
Somatosensory evoked potentials in severe traumatic brain injury: a blinded study
Authors: Sleigh James W. , Havill Jack H. , Frith Richard , Kersel Denyse , Marsh Nigel , Ulyatt David 
Published: May 2009

Object. Beginning in 1979, the results of somatosensory evoked potential (SSEP) monitoring have been used to predict outcome in patients who have suffered severe brain trauma. The data indicate that if the cortical components of the SSEPs were bilaterally absent, the outcome was always death or a vegetative state, but previous studies have not been blinded. The aims of this study were to correlate the results of SSEP recordings with the outcome in a prospectively blinded manner and to assess whether monitoring of SSEPs was a useful adjunct to clinical judgment in the prediction of outcome.Methods. The authors studied 105 severely head injured patients (median Glasgow Coma Scale score of 6) who were admitted to the Waikato Intensive Care Unit. The upper limb SSEPs were classified according to the central conduction time (CCT) as normal, of increased latency, or absent. The outcome as assessed using the Glasgow Outcome Scale (GOS) score was evaluated 12 months after the injury.Conclusions. Of 51 patients with a bilaterally normal CCT, 29 (57%) had a good outcome (GOS Score 5). Any delay in CCT was associated with a decreased incidence of good outcome (30%). Unilateral absence of the cortical component of the SSEP was usually associated with a poor outcome (death or severe disability), and bilateral absence was always associated with a poor outcome. The authors conclude that SSEPs correlate well with outcome and that this is not the result of investigator bias.
Side effects and mortality associated with use of phenytoin for early posttraumatic seizure prophylaxis
Authors: Haltiner Alan M. , Newell David W. , Temkin Nancy R. , Dikmen Sureyya S. , Winn H. Richard 
Published: May 2009

Object. The goals of this study were to determine if the use of phenytoin to prevent early posttraumatic seizures following head injury was associated with significant adverse side effects and also to determine if the reduction in early posttraumatic seizures after phenytoin administration was associated with a change in mortality rates in head-injured patients.Methods. The authors performed a secondary analysis of the data obtained in a prospective double-blind placebo-controlled study of 404 patients who were randomly assigned to receive phenytoin or placebo for the prevention of early and late posttraumatic seizures. The incidence of adverse drug effects during the first 2 weeks of treatment, however, was low and not significantly different between the treated and placebo groups. Hypersensitivity reactions occurred in 0.6% of the patients in the phenytoin-treated group compared with 0% in the placebo group (p = 1.0) during week 1, and in 2.5% of phenytoin-treated compared with 0% of placebo-treated patients (p = 0.12) for the first 2 weeks of treatment. Mortality rates were also similar in both groups. Although the mortality rate was higher in patients who developed seizures, this increase was related to the greater severity of the injuries sustained by these patients at the time of the original trauma.Conclusions. The results of this study indicate that the incidence of early posttraumatic seizure can be effectively reduced by prophylactic administration of phenytoin for 1 or 2 weeks without a significant increase in drug-related side effects. Reduction in posttraumatic seizure during the 1st week, however, was not associated with a reduction in the mortality rate.
Valproate therapy for prevention of posttraumatic seizures: a randomized trial
Authors: Temkin Nancy R. , Dikmen Sureyya S. , Anderson Gail D. , Wilensky Alan J. , Holmes Mark D. , Cohen Wendy , Newell David W. , Nelson Pamela , Awan Asaad , Winn H. Richard 
Published: May 2009

Object. Seizures frequently accompany moderate to severe traumatic brain injury. Phenytoin and carbamazepine are effective in preventing early, but not late, posttraumatic seizures. In this study the authors compare the safety and effectiveness of valproate with those of short-term phenytoin for prevention of seizures following traumatic brain injury.Methods. The study was a randomized, double-blind, single-center, parallel-group clinical trial. Treatment began within 24 hours of injury. One hundred thirty-two patients at high risk for seizures were assigned to receive a 1-week course of phenytoin, 120 were assigned to receive a 1-month course of valproate, and 127 were assigned to receive a 6-month course of valproate. The cases were followed for up to 2 years.The rates of early seizures were low and similar when using either valproate or phenytoin (1.5% in the phenytoin treatment group and 4.5% in the valproate arms of the study; p = 0.14, relative risk [RR] = 2.9, 95% confidence interval [CI] 0.7–13.3). The rates of late seizures did not differ among treatment groups (15% in patients receiving the 1-week course of phenytoin, 16% in patients receiving the 1-month course of valproate, and 24% in those receiving the 6-month course of valproate; p = 0.19, RR = 1.4, 95% CI 0.8–2.4). The rates of mortality were not significantly different between treatment groups, but there was a trend toward a higher mortality rate in patients treated with valproate (7.2% in patients receiving phenytoin and 13.4% in those receiving valproate; p = 0.07, RR = 2.0, 95% CI 0.9–4.1). The incidence of serious adverse events, including coagulation problems and liver abnormalities, was similar in phenytoin- and valproate-treated patients.Conclusions. Valproate therapy shows no benefit over short-term phenytoin therapy for prevention of early seizures and neither treatment prevents late seizures. There was a trend toward a higher mortality rate among valproate-treated patients. The lack of additional benefit and the potentially higher mortality rate suggest that valproate should not be routinely used for the prevention of posttraumatic seizures.
Intracranial volume change in childhood
Authors: Sgouros Spiros , Goldin J. Henry , Hockley Anthony D. , Wake Michael J. C. , Natarajan Kalyan 
Published: May 2009

Object. The goal of this study was to construct a model of normal changes in intracranial volume occurring throughout childhood from age 7 days to 15 years.Methods. Using the technique of segmentation on magnetic resonance images obtained in healthy children, intracranial volume was measured and plotted against age.Conclusions. Intracranial volume in the first few months of life is on average 900 cm3 in males and 600 cm3 in females. By the age of 15 years, it increases up to 1500 cm3 in males and 1300 cm3 in females, increased by factors of 1.6 and 2.1, respectively. By the time the child reaches 2 years of age, intracranial volume has reached 77% (1150 cm3 in males and 1000 cm3 in females) and, by 5 years, 90% (1350 cm3 in males and 1200 cm3 in females) of the volume observed at age 15 years. The change in intracranial volume that occurs with age is not linear, but there seems to be a segmental pattern. Three main periods can be distinguished, each lasting approximately 5 years (0–5, 5–10, and 10–15 years), during which the growth of intracranial volume is linear. Throughout childhood, males have higher intracranial volumes than females, with a similar growth pattern.
Treatment of cerebral origin spasticity with continuous intrathecal baclofen delivered via an implantable pump: long-term follow-up review of 18 patients
Authors: Rawicki Barry 
Published: May 2009

Object. The goal of this study was to assess the long-term benefits of managing severe spasticity by using continuous infusion of intrathecal baclofen delivered via an implantable pump.Methods. Eighteen patients with severe spasticity of cerebral origin, who failed to respond adequately to more conservative treatments, have been treated with continuous infusion of intrathecal baclofen delivered via an implanted pump. Follow-up review of these patients has lasted between 12 months and 9 years. The patients have been assessed using a variety of tools. Seventeen have had a significant reduction in tone and all have benefited by a reduced need for nursing care or increased function or both.Conclusions. Long-term continuous infusion of intrathecal baclofen delivered via an implantable pump offers an effective method for dealing with otherwise intractable spasticity.
Failure of the competitive N-methyl-d-aspartate antagonist Selfotel (CGS 19755) in the treatment of severe head injury: results of two Phase III clinical trials
Authors: Morris Gabrielle F. , Bullock Ross , Marshall Sharon Bowers , Marmarou Anthony , Maas Andrew , _ _ , Marshall Lawrence F. 
Published: May 2009

Object. Excessive activity of excitatory amino acids released after head trauma has been demonstrated to contribute to progressive injury in animal models and human studies. Several pharmacological agents that act as antagonists to the glutamate receptor have shown promise in limiting this progression. The efficacy of the N-methyl-d-aspartate receptor antagonist Selfotel (CGS 19755) was evaluated in two parallel studies of severely head injured patients, defined as patients with postresuscitation Glasgow Coma Scale scores of 4 to 8.Methods. A total of 693 patients were prospectively enrolled in two multicenter double-blind studies. Comparison between the treatment groups showed no significant difference with regard to demographic data, previous incidence of hypotension, and severity of injury. As the study progressed, the Safety and Monitoring Committee became concerned about possible increased deaths and serious brain-related adverse events in the treatment arm of the two head injury trials, as well as deaths in the two stroke trials being monitored concurrently. The Selfotel trials were stopped prematurely because of this concern and because an interim efficacy analysis indicated that the likelihood of demonstrating success with the agent if the studies had been completed was almost nil.Conclusions. Subsequently, more complete data analysis revealed no statistically significant difference in mortality rates in all cases between the two treatment groups in the head injury trials. In this report the authors examine the studies in detail and discuss the potential application of the data to future trial designs.
Pericollicular approaches to the rhomboid fossa. Part II. Neurophysiological basis
Authors: Strauss Christian , Romstöck Johann , Fahlbusch Rudolf 
Published: May 2009

Object. The authors describe their technique of electrophysiological mapping to assist pericollicular approaches into the rhomboid fossa.Methods. Surgical approaches to the rhomboid fossa can be optimized by direct electrical stimulation of superficially located nuclei and fibers. Electrophysiological mapping allows identification of facial nerve fibers, nuclei of the abducent and hypoglossal nerves, motor nucleus of the trigeminal nerve, and the ambiguous nucleus. Stimulation at the surface of the rhomboid fossa performed using the threshold technique allows localization above the area that is located closest to the surface. Simultaneous bilateral electromyographic (EMG) recordings from cranial motor nerves obtained during stimulation document the selectivity of evoked EMG responses. With respect to stimulation parameters and based on morphometric measurements, the site of stimulation can be assumed to be the postsynaptic fibers at the axonal cone. Strict limitation to 10 Hz with a maximum stimulation intensity not exceeding 2 mA can be considered safe. Direct side effects of electrical stimulation were not observed.Conclusions. Electrical stimulation based on morphometric data obtained on superficial brainstem anatomy defines two safe paramedian supra- and infracollicular approaches to the rhomboid fossa and is particulary helpful in treating intrinsic brainstem lesions that displace normal anatomical structures.