bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resumption of work after aneurysmal subarachnoid hemorrhage in middle-aged Japanese patients
Authors: Nishino Akiko , Sakurai Yoshiharu , Tsuji Ichiro , Arai Hiroaki , Uenohara Hiroshi , Suzuki Shinsuke , Li Jing-Hua 
Published: May 2009

Object. Previous reports on the results of treatment for aneurysmal subarachnoid hemorrhage (SAH) have been based only on activities of daily living after discharge, whereas resumption of work has received insufficient attention. Most Japanese work under a lifetime employment system, and it is best for those who have recovered from SAH to return to work for their previous employer. The present study was conducted to determine the extent to which discharged patients who have suffered an SAH resume their former occupations in Japan, focusing on those between 40 and 49 years of age, who usually have a strong desire to return to work.Methods. The participants consisted of 193 patients with SAH. Based on the results of telephone interviews or written questionnaires, their work status at 1 year after onset was analyzed.The work resumption rates for patients with Hunt and Kosnik neurological Grades 1 or 2 on admission were higher than for those with Grades 3 or 4 (p = 0.015) and lower for patients with basilar artery aneurysms than for those with aneurysms at other sites (p = 0.028). With regard to premorbid occupation, the work resumption rates were high (80%) for professionals and engineers, many of whom were public servants, or teachers at junior or senior high schools. The resumption rates were also high for primary industry workers (80%), but lowest (20%) for professional drivers (p = 0.04–0.001). The work resumption rate was lower for women than for men (p = 0.01).Conclusions. These findings indicate that resumption of work is determined not only by medical factors, but also by social factors including gender, type of occupation, employment system, and socioeconomic background.
Magnetoencephalographic mapping of the language-specific cortex
Authors: Papanicolaou Andrew C. , Simos Panagiotis G. , Breier Joshua I. , Zouridakis George , Willmore L. James , Wheless James W. , Constantinou Jules E. C. , Maggio William W. , Gormley William B. 
Published: May 2009

Object. In this paper the authors introduce a novel use of magnetoencephalography (MEG) for noninvasive mapping of language-specific cortex in individual patients and in healthy volunteers.Methods. The authors describe a series of six experiments in which normative MEG data were collected and the reliability, validity, and topographical accuracy of the data were assessed in patients who had also undergone the Wada procedure or language mapping through intraoperative cortical stimulation.Conclusions. Findings include: 1) receptive language—specific areas can be reliably activated by simple language tasks and this activation can be readily recorded in short MEG sessions; 2) MEG-derived maps of each individual are reliable because they remain stable over time and are independent of whether auditory or visual stimuli are used to activate the brain; and 3) these maps are also valid because they concur with results of the Wada procedure in assessing hemispheric dominance for language and with the results of cortical stimulation in identifying the precise topography of receptive language regions within the dominant hemisphere.Although the MEG mapping technique should be further refined, it has been shown to be efficacious by correctly identifying the language-dominant hemisphere and specific language-related regions within this hemisphere. Further development of the technique may render it a valuable adjunct for routine presurgical planning in many patients who harbor tumors or have epilepsy.
Optimizing accuracy in magnetic resonance imaging—guided stereotaxis: a technique with validation based on the anterior commissure—posterior commissure line
Authors: diPierro Charles G. , Francel Paul C. , Jackson Theodore R. , Kamiryo Toshifumi , Laws Edward R. 
Published: May 2009

Object. Some of the earliest successful frame-based stereotactic interventions directed toward the thalamus and basal ganglia depended on identifying the anterior commissure (AC) and posterior commissure (PC) in a sagittal ventriculogram and defining the intercommissural line that connects them in the midsagittal plane. The AC—PC line became the essential landmark for the localization of neuroanatomical targets in the basal ganglia and diencephalon and for relating them to stereotactic atlases.Stereotactic/functional neurosurgery has come to rely increasingly on magnetic resonance (MR) imaging guidance, and methods for accurately determining the AC—PC line on MR imaging are being developed. The goal of the present article is to present the authors' technique.Methods. The technique described uses MR sequences that minimize geometric distortion and registration error, thereby maximizing accuracy in AC—PC line determinations from axially displayed MR data. The technique is based on the authors' experience with the Leksell G-frame but can be generalized to other MR imaging—based stereotactic systems.This methodology has been used in a series of 62 stereotactic procedures in 47 adults (55 pallidotomies and seven thalamotomies) with preliminary results that compare favorably with results reported when using microelectrode recordings. The measurements of the AC—PC line reported here also compare favorably with those based on ventriculography and computerized tomography scanning.Conclusions. The methodology reported here is critical in maintaining the accuracy and utility of MR imaging as its role in modern stereotaxy expands. Accurate parameters such as these aid in ensuring the safety, efficacy, and reproducibility of MR-guided stereotactic procedures.
Presence of vitronectin and activated complement factor C9 on ventriculoperitoneal shunts and temporary ventricular drainage catheters
Authors: Lundberg Fredrik , Li Dai-Qing , Falkenback Dan , Lea Tor , Siesjö Peter , Söderström Sven , Kudryk Bohdan J. , Tegenfeldt Jonas O. , Nomura Sadahiro , Ljungh Åsa 
Published: May 2009

Object. The pathogenesis of cerebrospinal fluid (CSF) shunt infection is characterized by staphylococcal adhesion to the polymeric surface of the shunt catheter. Proteins from the CSF—fibronectin, vitronectin, and fibrinogen—are adsorbed to the surface of the catheter immediately after insertion. These proteins can interfere with the biological systems of the host and mediate staphylococcal adhesion to the surface of the catheter. In the present study, the presence of fibronectin, vitronectin, and fibrinogen on CSF shunts and temporary ventricular drainage catheters is shown. The presence of fragments of fibrinogen is also examined.Methods. The authors used the following methods: binding radiolabeled antibodies to the catheter surface, immunoblotting of catheter eluates, and scanning force microscopy of immunogold bound to the catheter surface. The immunoblot showed that vitronectin was adsorbed in its native form and that fibronectin was degraded into small fragments. Furthermore, the study demonstrated that the level of vitronectin in CSF increased in patients with an impaired CSF—blood barrier. To study complement activation, an antibody that recognizes the neoepitope of activated complement factor C9 was used. The presence of activated complement factor C9 was shown on both temporary catheters and shunts.Conclusions. Activation of complement close to the surface of an inserted catheter could contribute to the pathogenesis of CSF shunt infection.
Growth of precultured human glioma biopsy specimens in nude rat brain
Authors: Engebraaten Olav , Hjortland Geir Olav , Hirschberg Henry , Fodstad Øystein 
Published: May 2009

Object. The aim of this study was to develop an improved animal model for brain tumor study. The need for better and more relevant brain tumor models is generally acknowledged. Glioma tissue can be cultured directly from the biopsy specimen as tumor spheroids. Using such precultured tissue, a new in vivo model for studying human gliomas was established.Methods. Precultured small tumor spheroids (< 300 µm) prepared from cell lines or tumor biopsy fragments were injected into the brains of immunodeficient rats by using a 5-µl Hamilton syringe that had a piston in the needle. Tumors could be established by injecting a single spheroid derived from the U-87MG cell line, whereas inoculation of 10 spheroids resulted in a tumor take comparable to that attained with injection of 106 single cells. Biopsy specimens obtained from six patients who underwent surgery for glioblastoma multiforme were cultured as organotypic spheroids for 11 to 18 days before inoculation into the rats. The animals were killed 3 months after spheroid implantation. Microscopic examination revealed tumor growth in 87.5 to 100% of the animals inoculated with tumor spheroids from all but one of the tumor biopsy specimens. Extensive invasion and cell migration along the nerve tracts of the corpus callosum was found in tumors that originated from four of the six biopsy specimens.Conclusions. This approach, in which spheroids from precultured biopsy specimens are injected into the brains of immunodeficient animals, provides new means for experimental studies of human malignant brain tumors in a clinically relevant animal model.
Outcomes after stereotactically guided pallidotomy for advanced Parkinson's disease
Authors: Kondziolka Douglas , Bonaroti Eugene , Baser Susan , Brandt Fran , Kim Young Soo , Lunsford L. Dade 
Published: May 2009

Object. Parkinson's disease (PD) is a prevalent neurodegenerative disorder that becomes refractory to medication as the disease progresses. Although in the past 5 years increasing numbers of patients have undergone stereotactically guided posteroventral pallidotomy for advanced PD, the safety and efficacy of surgery remains to be documented. The goal in this study was to determine the potential operative morbidity and types of functional outcomes by using validated PD rating scales and a patient survey.Methods. In a prospective analysis of a consecutive surgical series the authors evaluated 58 patients with advanced PD who ranged in age from 40 to 79 years (mean 67 years) and who had undergone surgery between 1994 and 1997. They used a patient survey and the Unified Parkinson's Disease Rating Scale (UPDRS) to study patients during periods of medication administration (“on”) and withdrawal (“off”; mean off score before surgery = 96).Temporary surgical morbidity was found in four patients (6.9%), three of whom developed transient dysarthria and one of whom exhibited transient confusion (1.7%). One patient had persistent dysarthria (1.7%). No patient developed a visual field deficit or sustained a brain hemorrhage. All patients were discharged from the hospital within 24 hours. Significant postsurgical improvements were noted in the UPDRS off-period total and motor scores, as well as in tremor, rigidity, bradykinesia, and contralateral dyskinesia (p < 0.005). Improvements persisted in dyskinesia and tremor for the 21 patients who were evaluated past 1 year. The authors found no improvement in any on-period symptoms except dyskinesia. Thirty-one (61%) of 51 patients surveyed reported functional gains and/or dramatic improvement in symptoms, 17 (33%) reported symptomatic improvement without functional gains, and three (6%) had minimal or no change in symptoms. No change in the mini mental state examination score was noted during follow up. There were no significant postoperative changes in the use of medication.Conclusions. In advanced PD associated with either a medically refractory state with significant off periods or levodopa-induced dyskinesias, magnetic resonance imaging—guided pallidotomy with macrostimulation was associated with minimal morbidity and yet significantly reduced dyskinesia and off-period disability. These improvements were of value to the patient and persisted beyond the 1st year.
The efficacy of an abbreviated course of nimodipine in patients with good-grade aneurysmal subarachnoid hemorrhage
Authors: Toyota Brian D. 
Published: May 2009

Object. Nimodipine therapy has become a standard component of the treatment regimen used in patients with aneurysmal subarachnoid hemorrhage (SAH). Its prescribed use at 60 mg every 4 hours for 21 days is based on reputable, randomized prospective studies. However, because only 20 to 30% of patients with SAH suffer clinical cerebral vasospasm, it is clear that most patients do not actually need the drug. Of course, this fact is not evident until several treatment days have passed. It is common practice, without well-documented consequences, to terminate nimodipine therapy before 21 days in certain clinical circumstances. The aim of this study was to evaluate the effectiveness of abbreviating the duration of nimodipine treatment in the setting of a good-grade aneurysmal SAH.Methods. A retrospective clinical review was made of 90 consecutive patients who experienced a Hunt and Hess Grade I through III aneurysmal SAH and were treated with nimodipine for 15 days or less.Conclusions. None of the patients studied suffered a delayed neurological deficit as a result of the abbreviated course of nimodipine.
Trigeminocardiac reflex during surgery in the cerebellopontine angle
Authors: Schaller Bernhard , Probst Rudolf , Strebel Stephan , Gratzl Otmar 
Published: May 2009

Object. In different experimental studies authors have analyzed the autonomic responses elicited by the electrical, mechanical, or chemical stimulation of the trigeminal nerve system. The trigeminocardiac reflex (TCR) is a well-recognized phenomenon that consists of bradycardia, arterial hypotension, apnea, and gastric hypermotility. It occurs during ocular surgery and during other manipulations in and around the orbit. Thus far, it has not been shown that central stimulation of the trigeminal nerve can also cause this reflex.Methods. The TCR was defined as clinical hypotension with a drop in mean arterial blood pressure (MABP) of more than 20% and bradycardia lower than 60 beats/minute. Pre-, intra-, and postoperative heart rate (HR) and MABP were reviewed retrospectively in 125 patients who underwent surgery for tumors of the cerebellopontine angle (CPA), and they were divided into two groups on the basis of the occurrence of the TCR during surgery. Of the 125 patients, 14 (11%) showed evidence of the TCR during dissection of the tumor near the trigeminal nerve at the brainstem. Their HRs fell 38% and their MABPs fell 48% during operative procedures as compared with preoperative levels. After cessation of manipulation, the HRs and the MABPs returned to preoperative levels. Risk factors for the occurrence of the TCR were compared with results from the literature.Conclusions. The authors' results show the possibility of occurrence of a TCR during manipulation of the central part of the trigeminal nerve when performing surgery in the CPA.
Dutch Normal-Pressure Hydrocephalus Study: the role of cerebrovascular disease
Authors: Boon Agnita J. W. , Tans Joseph T. J. , Delwel Ernst J. , Egeler-Peerdeman Saskia M. , Hanlo Patrick W. , Wurzer Hans A. L. , Hermans Jo 
Published: May 2009

Object. This study was conducted to determine the prevalence of cerebrovascular disease and its risk factors among patients with normal-pressure hydrocephalus (NPH) and to assess the influence of these factors on the outcome of shunt placement.Methods. A cohort of 101 patients with NPH underwent shunt placement and was followed for 1 year. Gait disturbance and dementia were quantified using an NPH scale and handicap was determined using a modified Rankin scale (mRS). Primary outcome measures consisted of the differences between preoperative and last NPH scale and mRS scores. The presence of risk factors such as hypertension, diabetes mellitus, cardiac disease, peripheral vascular disease, male gender, and advancing age was recorded. Cerebrovascular disease was defined as a history of stroke or a computerized tomography (CT) scan revealing infarcts or moderate-to-severe white matter hypodense lesions.The prevalence of risk factors for cerebrovascular disease was higher in the 45 patients with cerebrovascular disease than the 56 without it. Risk factors did not influence outcome after shunt placement. Intent-to-treat analysis revealed that the mean improvement in the various scales was significantly less for patients with a history of stroke (14 patients), CT scans revealing infarctions (13), or white matter hypodense lesions (32 patients) than for those without cerebrovascular disease. The proportion of patients who responded to shunt placement was also significantly lower among patients with than those without cerebrovascular disease (p = 0.02).Conclusions. The authors identified a subgroup of patients with NPH and cerebrovascular disease who showed disappointing results after shunt placement. Cerebrovascular disease was an important predictor of poor outcome.
Sylvian aqueduct syndrome and global rostral midbrain dysfunction associated with shunt malfunction
Authors: Cinalli Giuseppe , Sainte-Rose Christian , Simon Isabelle , Lot Guillaume , Sgouros Spiros 
Published: May 2009

Object. This study is a retrospective analysis of clinical data obtained in 28 patients affected by obstructive hydrocephalus who presented with signs of midbrain dysfunction during episodes of shunt malfunction.Methods. All patients presented with an upward gaze palsy, sometimes associated with other signs of oculomotor dysfunction. In seven cases the ocular signs remained isolated and resolved rapidly after shunt revision. In 21 cases the ocular signs were variably associated with other clinical manifestations such as pyramidal and extrapyramidal deficits, memory disturbances, mutism, or alterations in consciousness. Resolution of these symptoms after shunt revision was usually slow. In four cases a transient paradoxical aggravation was observed at the time of shunt revision. In 11 cases ventriculocisternostomy allowed resolution of the symptoms and withdrawal of the shunt.Simultaneous supratentorial and infratentorial intracranial pressure recordings performed in seven of the patients showed a pressure gradient between the supratentorial and infratentorial compartments, with a higher supratentorial pressure before shunt revision. Inversion of this pressure gradient was observed after shunt revision and resolution of the gradient was observed in one case after third ventriculostomy. In six recent cases, a focal midbrain hyperintensity was evidenced on T2-weighted magnetic resonance imaging sequences at the time of shunt malfunction. This rapidly resolved after the patient underwent third ventriculostomy.Conclusions. It is probable that in obstructive hydrocephalus, at the time of shunt malfunction, the development of a transtentorial pressure gradient could initially induce a functional impairment of the upper midbrain, inducing upward gaze palsy. The persistence of the gradient could lead to a global dysfunction of the upper midbrain. Third ventriculostomy contributes to equalization of cerebrospinal fluid pressure across the tentorium by restoring free communication between the infratentorial and supratentorial compartments, resulting in resolution of the patient's clinical symptoms.
Surgical treatment of craniopharyngiomas: experience with 168 patients
Authors: Fahlbusch Rudolf , Honegger Jürgen , Paulus Werner , Huk Walter , Buchfelder Michael 
Published: May 2009

Object. The goal of this study was to assess the outcome of surgical management in 168 consecutive patients harboring craniopharyngiomas treated between January 1983 and April 1997.Methods. In 148 patients undergoing initial (primary) surgery, the pterional approach was most frequently used (39.2%), followed by the transsphenoidal approach (23.6%). For large retrochiasmatic craniopharyngiomas, the bifrontal interhemispheric approach was used increasingly over the pterional approach and led to improved surgical results. Total tumor removal was accomplished in 45.7% of transcranial and 85.7% of transsphenoidal procedures. The main reasons for incomplete removal were attachment to and/or infiltration of the hypothalamus, major calcifications, and attachment to vascular structures. The success rate in total tumor removal was inferior in the cases of tumor recurrence. The operative mortality rate in transcranial surgery was 1.1% in primary cases and 10.5% in cases of tumor recurrence. No patient died in the group that underwent transsphenoidal surgery. The rate of recurrence-free survival after total removal was 86.9% at 5 years and 81.3% at 10 years. In contrast, the 5-year recurrence-free survival rate was only 48.8% after subtotal removal and 41.5% after partial removal. Following primary surgery, the actuarial survival rate was 92.7% at 10 years, with the best results after complete tumor removal. At last follow up, 117 (79%) of 148 patients who underwent primary surgery were independent and without impairment.Conclusions. Total tumor removal while avoiding hazardous intraoperative manipulation provides favorable early results and a high rate of long-term control in craniopharyngiomas.
Variables affecting convection-enhanced delivery to the striatum: a systematic examination of rate of infusion, cannula size, infusate concentration, and tissue—cannula sealing time
Authors: Chen Michael Y. , Lonser Russell R. , Morrison Paul F. , Governale Lance S. , Oldfield Edward H. 
Published: May 2009

Object. Although recent studies have shown that convection can be used to distribute macromolecules within the central nervous system (CNS) in a homogeneous, targeted fashion over clinically significant volumes and that the volume of infusion and target location (gray as opposed to white matter) influence distribution, little is known about other factors that may influence optimum use of convection-enhanced distribution. To understand the variables that affect convective delivery more fully, we examined the rate of infusion, delivery cannula size, concentration of infusate, and preinfusion sealing time.Methods. The authors used convection to deliver 4 µl of 14C-albumin to the striatum of 40 rats. The effect of the rate of infusion (0.1, 0.5, 1, and 5 µl/minute), cannula size (32, 28, and 22 gauge), concentration of infusate (100%, 50%, and 25%), and preinfusion sealing time (0 and 70 minutes) on convective delivery was examined using quantitative autoradiography, National Institutes of Health image analysis software, scintillation analysis, and histological analysis.Higher rates of infusion (1 and 5 µl/minute) caused significantly (p < 0.05) more leakback of infusate (22.7 ± 11.7% and 30.3 ± 7.8% [mean ± standard deviation], respectively) compared with lower rates (0.1 µl/minute [4 ± 3.6%] and 0.5 µl/minute [5.2 µ 3.6%]). Recovery of infusate was significantly (p < 0.05) higher at the infusion rate of 0.1 µl/minute (95.1 ± 2.8%) compared with higher rates (85.2 ± 4%). The use of large cannulae (28 and 22 gauge) produced significantly (p < 0.05) more leakback (35.7 ± 8.1% and 21.1 ± 7.5%, respectively) than the smaller cannula (32 gauge [5.2 ± 3.6%]). Varying the concentration of the infusate and the preinfusion sealing time did not alter the volume of distribution, regional distribution, or infusate recovery.Conclusions. Rate of infusion and cannula size can significantly affect convective distribution of molecules, whereas preinfusion sealing time and variations in infusate concentration have no effect in this small animal model. Understanding the parameters that influence convective delivery within the CNS can be used to enhance delivery of potentially therapeutic agents in an experimental setting and to indicate the variables that will need to be considered for optimum use of this approach for drug delivery in the clinical setting.