bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of neuroradiological imaging, neurological examination, and symptom status in follow-up assessment of patients with high-grade gliomas
Authors: Galanis Evanthia , Buckner Jan C. , Novotny Paul , Morton Roscoe F. , McGinnis William L. , Dinapoli Robert , Schomberg Paula , O'Fallon Judith R. 
Published: May 2009

Object. It is standard practice for the oncological follow-up of patients with brain tumors (especially in the setting of clinical trials) to include neurological examination and neuroradiological studies such as computerized tomography (CT) or magnetic resonance (MR) imaging in addition to evaluation of the patients' symptomatology and performance score. The validity of this practice and its impact on the welfare of patients with high-grade gliomas has not been adequately assessed. The purpose of this study is to provide such an assessment.Methods. The authors studied 231 similarly treated patients who were participating in three prospective North Central Cancer Treatment Group or Mayo Clinic trials who developed progressive disease during follow up. According to the protocol, the symptom status, performance score, results of neurological examination, and CT or MR status were recorded prospectively in each patient at each evaluation (every 6–8 weeks).At progression, 177 (77%) of 231 patients experienced worsening of their baseline symptoms or they developed new ones. In the remaining 54 asymptomatic patients (23%), neuroradiological imaging revealed the progression. Asymptomatic progression was more likely to be detected on MR imaging compared with CT studies (p < 0.01). In no asymptomatic patient was progression detected on neurological examination alone. The median survival time after tumor recurrence was 13.3 weeks in symptomatic patients compared with 41.7 weeks in the asymptomatic group (p < 0.0001). Asymptomatic patients were more aggressively treated, with surgery (p < 0.0001) and second-line chemotherapy (p < 0.0002). Multivariate analysis of survival time following first progression by using both classification and regression trees and Cox models showed that treatment at recurrence was the most important prognostic variable.Conclusions. Symptoms are the most frequent indicators of progression in patients with high-grade gliomas (77%). All asymptomatic progressions were detected on neuroradiological studies; MR imaging was more likely than CT scanning to reveal asymptomatic recurrences. Survival after disease progression was significantly longer in asymptomatic patients and could be related both to treatment following progression and to other favorable prognostic factors such as performance score.
Computer-assisted neurosurgery by using a noninvasive vacuum-affixed dental cast that acts as a reference base: another step toward a unified approach in the treatment of brain tumors
Authors: Bale Reto J. , Burtscher Johannes , Eisner Wilhelm , Obwegeser Alois A. , Rieger Michael , Sweeney Reinhart A. , Dessl Andreas , Giacomuzzi Salvatore M. , Twerdy Klaus , Jaschke Werner 
Published: May 2009

Object. The purpose of the study was to evaluate the use of the Vogele-Bale-Hohner (VBH) mouthpiece, which is attached to the patient's upper jaw by negative pressure, for patient—image registration and for tracking the patient's head during image-guided neurosurgery.Methods. A dynamic reference frame (DRF) is reproducibly mounted on the mouthpiece. Reference points, optimally distributed and attached to the mouthpiece, are used for registration in the patient's absence on the day before surgery. In the operating room, the mouthpiece and DRF are precisely repositioned using a vacuum, and the patient's anatomical structures are automatically registered to corresponding ones on the image. Experimental studies and clinical experiences in 10 patients confirmed repeated (rigid body) localization accuracy in the range of 0 to 2 mm, throughout the entire surgery despite movements by the patient.Conclusions. Because of its noninvasive, rigid, reliable, and reproducible connection to the patient's head, the VBH vacuum-affixed mouthpiece grants the registration device an accuracy comparable to invasive fiducial markers.
Headaches in patients with radiosurgically treated occipital arteriovenous malformations
Authors: Kurita Hiroki , Ueki Keisuke , Shin Masahiro , Kawamoto Shunsuke , Sasaki Tomio , Tago Masao , Kirino Takaaki 
Published: May 2009

Object. The goal of this study was to determine the prevalence, characteristics, and radiosurgical outcomes of headaches associated with occipital arteriovenous malformations (AVMs).Methods. The authors reviewed the medical records of 37 consecutive patients with occipital AVMs who had been treated by radiosurgery to identify the radiological features of the AVMs before and after treatment and the clinical features and outcomes of headaches described in accordance with the criteria of the International Headache Society (IHS).Thirty-six patients (97.3%) were followed for a mean period of 46.6 months. The median volume of the AVMs was 1.9 cm3, to which a mean radiation dose of 21.6 Gy was delivered. In the entire study group, periodic headaches were found in 17 patients (45.9%), of whom seven (18.9%) suffered from migraines with the characteristic visual aura. Migraine was predominantly found in patients with right-sided (p = 0.038) or laterally located (p = 0.025) AVMs. Factors associated with a higher incidence of any type of headache included larger nidus volume (p = 0.02), tortuous change of feeding artery (p = 0.036), and cortical drainage with reflux in the superior sagittal sinus (p = 0.032). The actuarial rate of angiographic obliteration was 71.6% at 3 years. Headaches resolved or improved in 12 (70.6%) of 17 patients, including six (85.7%) of seven with migraine. The outcome of headache closely correlated with the obliteration results of the AVM (p = 0.002).Conclusions. A portion of occipital AVMs do cause headaches that satisfy the current IHS criteria for migraine, and the prevalence varies by the topography of the lesion. Radiosurgery can resolve headaches in the majority of treated patients.
Continuous monitoring of regional cerebral blood flow: experimental and clinical validation of a novel thermal diffusion microprobe
Authors: Vajkoczy Peter , Roth Harry , Horn Peter , Lucke Thomas , Thomé Claudius , Hubner Ulrich , Martin Gregory T. , Zappletal Christina , Klar Ernst , Schilling Lothar , Schmiedek Peter 
Published: May 2009

Object. Current clinical neuromonitoring techniques lack adequate surveillance of cerebral perfusion. In this article, a novel thermal diffusion (TD) microprobe is evaluated for the continuous and quantitative assessment of intraparenchymal regional cerebral blood flow (rCBF).Methods. To characterize the temporal resolution of this new technique, rCBF measured using the TD microprobe (TD-rCBF) was compared with rCBF levels measured by laser Doppler (LD) flowmetry during standardized variations of CBF in a sheep model. For validation of absolute values, the microprobe was implanted subcortically (20 mm below the level of dura) into 16 brain-injured patients, and TD-rCBF was compared with simultaneous rCBF measurements obtained using stable xenon-enhanced computerized tomography scanning (sXe-rCBF). The two techniques were compared using linear regression analysis as well as the Bland and Altman method.Stable TD-rCBF measurements could be obtained throughout all 3- to 5-hour sheep experiments. During hypercapnia, TD-rCBF increased from 49.3 ± 15.8 ml/100 g/min (mean ± standard deviation) to 119.6 ± 47.3 ml/100 g/min, whereas hypocapnia produced a decline in TD-rCBF from 51.2 ± 12.8 ml/100 g/min to 39.3 ± 5.6 ml/100 g/min. Variations in mean arterial blood pressure revealed an intact autoregulation with pressure limits of approximately 65 mm Hg and approximately 170 mm Hg. After cardiac arrest TD-rCBF declined rapidly to 0 ml/100 g/min. The dynamics of changes in TD-rCBF corresponded well to the dynamics of the LD readings. A comparison of TD-rCBF and sXe-rCBF revealed a good correlation (r = 0.89; p <0.0001) and a mean difference of 1.1 ± 5.2 ml/100 g/min between the two techniques.Conclusions. The novel TD microprobe provides a sensitive, continuous, and real-time assessment of intraparenchymal rCBF in absolute flow values that are in good agreement with sXe-rCBF measurements. This study provides the basis for the integration of TD-rCBF into multimodal monitoring of patients who are at risk for secondary brain injury.
Survival of adult rat retinal ganglion cells with regrown axons in peripheral nerve grafts: a comparison of graft attachment with suture or fibrin glue
Authors: Robinson Grant A. , Madison Roger D. 
Published: May 2009

Object. The goal of this study was to examine whether the method of attachment of a peripheral nerve graft would have an effect on retinal ganglion cell (RGC) regeneration.Methods. The number of adult rat RGCs with regrown axons in a peripheral nerve graft was compared under two grafting conditions: 1) attachment of the graft to the optic nerve stump made using a suture; and 2) attachment made using fibrin glue. Counts of RGCs retrogradely labeled with FluoroGold from the grafts 1 month after attachment revealed approximately seven times the number of RGCs in the fibrin-glue group compared with the suture group.Conclusions. The use of fibrin glue may be a useful tool for enhancing the regrowth of central nervous system neuron axons into peripheral nervous system grafts.
Wild-type p53—dependent etoposide-induced apoptosis mediated by caspase-3 activation in human glioma cells
Authors: Yin Dali , Tamaki Norihiko , Kokunai Takashi 
Published: May 2009

Object. In an attempt to understand the roles of several apoptosis-related genes in human glioma cells, the authors investigated the relationship of wild-type p53, interleukin-1β—converting enzyme (ICE), caspase-3 (CPP32), bax, and bcl-2 to the apoptotic response of three glioma cell lines after treatment with etoposide.Methods. A human glioma cell line (U-87MG) that expresses wild-type p53, one that expresses mutant p53 (T-98G), and a T-98G derivative (T-98G/p53) that was transfected with a wild-type p53 expression vector (pCDM8-p53/neo) were used. Cell growth inhibition in response to etoposide was quantified using a modified methylthiazol tetrazolium colorimetric assay. Induction of apoptosis was evaluated using Hoechst 33258 staining and a DNA fragmentation assay. To study the expression of the apoptosis-related proteins and messenger RNAs in the three glioma cell lines, Western blotting and polymerase chain reaction were performed. A caspase assay and Western blot analysis were used to assess CPP32 and ICE protease activity. A CPP32 inhibition assay was used to determine whether a specific CPP32 inhibitor, DEVD-CHO, affects the apoptosis induced by etoposide in malignant glioma cells. Etoposide significantly inhibited the growth of U-87MG and T-98G/p53 cells in a dose-dependent manner compared with the growth of the T-98G cells. Treatment with low concentrations of etoposide resulted in the increased expression of wild-type p53; it also initiated CPP32 activity and induced apoptosis in the U-87MG cells. Apoptosis was not induced in T-98G cells at low concentrations of etoposide, although it was induced at high concentrations. Furthermore, low concentrations of etoposide also induced apoptosis in the T-98G/p53 cells by enhancing the expression of transfected wild-type p53, decreasing the expression of bcl-2, and activating CPP32 activity. However, etoposide did not alter the expression of bax and did not initiate ICE activity in these three glioma cell lines. Etoposide-induced apoptosis can be suppressed by the CPP32 inhibitor DEVD-CHO.Conclusions. These findings indicate that wild-type p53, CPP32, and bcl-2 may mediate apoptosis induced by etoposide. Forced expression of wild-type p53 increases etoposide cytotoxicity in human glioma cells by inducing apoptosis and may have important therapeutic implications.
Effect of initially limited resuscitation in a combined model of fluid-percussion brain injury and severe uncontrolled hemorrhagic shock
Authors: Stern Susan A. , Zink Brian J. , Mertz Michelle , Wang Xu , Dronen Steven C. 
Published: May 2009

Object. Studies of isolated uncontrolled hemorrhage have indicated that initial limited resuscitation improves survival. Limited resuscitation has not been studied in combined traumatic brain injury and uncontrolled hemorrhage. In this study the authors evaluated the effects of limited resuscitation on outcome in combined fluid-percussion injury (FPI) and uncontrolled hemorrhage.Methods. Twenty-four swine weighing 17 to 24 kg each underwent FPI (3 atm) and hemorrhage to a mean arterial pressure (MAP) of 30 mm Hg in the presence of a 4-mm aortic tear. Group I (nine animals) was initially resuscitated to a goal MAP of 60 mm Hg; Group II (nine animals) was resuscitated to a goal MAP of 80 mm Hg; and Group III (control; six animals) was not resuscitated. After 60 minutes, the aortic hemorrhage was controlled and the animals were resuscitated to baseline physiological parameters and observed for 150 minutes.Mortality rates were 11%, 50%, and 100% for Groups I, II, and III, respectively (Fisher's exact test; p = 0.002). The total hemorrhage volume was greater in Group II (69 ± 32 ml/kg), as compared with Group I (41 ± 18 ml/kg) and Group III (37 ± 3 ml/kg) according to analysis of variance (p < 0.05). In surviving animals, cerebral perfusion pressure, cerebral blood flow (CBF), cerebral venous O2 saturation (ScvO2), and cerebral metabolic rate of O2 did not differ among groups. Although CBF was approximately 50% of baseline during the period of limited resuscitation in Group I, ScvO2 remained greater than 60%, and arteriovenous O2 differences remained within normal limits.Conclusions. In this model of FPI and uncontrolled hemorrhage, early aggressive resuscitation, which is currently recommended, resulted in increased hemorrhage and failure to optimize cerebrovascular parameters. In addition, a 60-minute period of moderate hypotension (MAP = 60 mm Hg) was well tolerated and did not compromise cerebrovascular hemodynamics, as evidenced by physiological parameters that remained within the limits of cerebral autoregulation.
Immediate coma following inertial brain injury dependent on axonal damage in the brainstem
Authors: Smith Douglas H. , Nonaka Masahiro , Miller Reid , Leoni Matthew , Chen Xiao-Han , Alsop David , Meaney David F. 
Published: May 2009

Object. Immediate and prolonged coma following brain trauma has been shown to result from diffuse axonal injury (DAI). However, the relationship between the distribution of axonal damage and posttraumatic coma has not been examined. In the present study, the authors examine that relationship.Methods. To explore potential anatomical origins of posttraumatic coma, the authors used a model of inertial brain injury in the pig. Anesthetized miniature swine were subjected to a nonimpact-induced head rotational acceleration along either the coronal or axial plane (six pigs in each group). Immediate prolonged coma was consistently produced by head axial plane rotation, but not by head coronal plane rotation. Immunohistochemical examination of the injured brains revealed that DAI was produced by head rotation along both planes in all animals. However, extensive axonal damage in the brainstem was found in the pigs injured via head axial plane rotation. In these animals, the severity of coma was found to correlate with both the extent of axonal damage in the brainstem (p < 0.01) and the applied kinetic loading conditions (p < 0.001). No relationship was found between coma and the extent of axonal damage in other brain regions.Conclusions. These results suggest that injury to axons in the brainstem plays a major role in induction of immediate posttraumatic coma and that DAI can occur without coma.
Comparison of two commercially available near-infrared spectroscopy instruments for cerebral oximetry
Authors: Cho Hun , Nemoto Edwin M. , Sanders Mark , Fernandez Karl , Yonas Howard 
Published: May 2009

✓ Two near-infrared spectroscopy (NIRS) devices were compared with regard to their responses to changes in cerebral hemoglobin oxygenation induced by hypoxia and hypercapnia in five healthy volunteers.Sensors belonging to each NIRS device were placed on opposite sides of the volunteer's forehead. The INVOS3100A device, approved by the United States Food and Drug Administration, records the percentage of oxyhemoglobin (HbO2) saturation and the investigational NIRO500 device records absolute changes in HbO2, deoxyhemoglobin, and total hemoglobin in micromolar concentrations referenced to an arbitrary baseline. The volunteers breathed separate mixtures of 7% CO2 in O2 and 10% O2 for 5 minutes in random order. Arterial blood pressure, end-tidal CO2 (ETCO2), arterial O2 saturation, and electrocardiographic data were continuously monitored.Hypercapnia increased (p < 0.01) ETCO2 from 42 ± 2 to 56 ± 3 mm Hg (mean ± standard deviation), resulting in a 7.3 ± 0.2% increase (p < 0.005) in cerebral HbO2 saturation detected by the INVOS3100A device and an 11.6 ± 3 µM increase (p < 0.0008) in HbO2 detected by the NIRO500. Hypoxia decreased (p < 0.01) arterial HbO2 saturation from 98 ± 1 to 87 ± 3%, causing a 5.1 ± 1.2% decrease (p < 0.01) in the percentage of HbO2 saturation detected by the INVOS3100A device and a 9.7 ± 6.3 µM decrease in HbO2 detected by the NIRO500.The responses of the NIRO500 and the INVOS3100A instruments to changes in cerebral oxygenation resulting from hypercapnia and hypoxia were generally similar; however, responses tended to be greater when recorded by the NIRO500 device, perhaps because, unlike the INVOS3100A device, the NIRO500 does not correct for skin and bone contamination.
The remodeling technique of balloon-assisted Guglielmi detachable coil placement in wide-necked aneurysms: experience at the University of Illinois at Chicago
Authors: Aletich Victor A. , Debrun Gerard M. , Misra Mukesh , Charbel Fady , Ausman James I. 
Published: May 2009

Object. Reports in the literature have offered discussions of the feasibility, efficacy, and safety of balloon-assisted Guglielmi detachable coil (GDC) placement in wide-necked intracranial aneurysms, which was first described by Jacques Moret as the “remodeling technique.” In this article the authors summarize their results in a subset of aneurysms treated with GDCs using the remodeling technique.Methods. This report contains a retrospective analysis of 72 patients with 75 aneurysms who underwent 79 endovascular procedures performed using the remodeling technique. Morphological outcome was determined at the end of each procedure and by reviewing available follow-up angiograms. Clinical assessments and outcomes are reported using a modified Glasgow Outcome Scale.Coils were placed in 66 (88%) of 75 aneurysms selected for treatment. In eight aneurysms (11%) treatment failures occurred due to the tortuosity of the vessel used to reach the aneurysms or because of balloon inadequacies.Incorporating all available follow-up data the authors found that 50 (78%) of 64 aneurysms were completely or subtotally (> 95%) occluded and eight (12%) of 64 were incompletely (< 95%) occluded. Since the time of coil placement, eight aneurysms have progressed to complete occlusion and another five have exhibited progressive thrombosis on follow-up angiograms. In three aneurysms there has been neck remnant growth. Surgical clipping was performed to treat six aneurysms after an initial coil placement procedure. Permanent incidences of morbidity were limited to four patients and there were three deaths directly related to the procedure.Conclusions. The remodeling technique shows promise in increasing the number of cerebral aneurysms amenable to treatment by endovascular coil placement, and offers an alternative approach to aneurysms that have met with failed surgical treatment or are surgically inaccessible. Long-term follow-up review is needed to determine the final outcome of aneurysms treated by this technique.
Role of the mode of sensory stimulation in presurgical brain mapping in which functional magnetic resonance imaging is used
Authors: Le Rumeur Elisabeth , Allard Michèle , Poiseau Eric , Jannin Pierre 
Published: May 2009

Object. The aim of this study was to evaluate different types of sensory stimulation used to distinguish between microvasculature and venous drainage on functional magnetic resonance (fMR) images with blood oxygen level—dependent (BOLD) contrast.Methods. Seven volunteers received three sensory stimulations. One consisted of small discontinuous automated pokes to the ventral aspect of the right thumbtip. The other two were delivered by the investigator, who vigorously brushed the ventral aspect of the right thumbtip either alone or in combination with the thenar region. Seven contiguous axial slices of the head were acquired using echoplanar fMR imaging during each mode of stimulation. Box-car analysis and Student's t-test were performed. Cluster analysis was used to determine significant differences between rest and activation phases.The major findings were 1) that a discontinuous sensory stimulation involving a small skin area was able to evoke a limited activated area in the postcentral gyrus with a low activation index (AI [2%]); 2) that this limited activated area was included in the activated area elicited by the continuous sensory stimulations; and 3) that this also evoked multiple activated areas exhibiting AIs of either approximately 2% or greater than 5%. This indicated that the limited discontinuous tactile stimulation evoked a BOLD-contrast fMR image essentially of microvasculature, whereas the more extensive continuous stimulations evoked a BOLD-contrast fMR image in both microvasculature and venous drainage.Conclusions. Different sensory stimulations are necessary to differentiate primary sensory cortex from venous drainage for presurgical brain mapping.
Mobile computerized tomography scanning in the neurosurgery intensive care unit: increase in patient safety and reduction of staff workload
Authors: Gunnarsson Thorsteinn , Theodorsson Annette , Karlsson Per , Fridriksson Steen , Boström Sverre , Persliden Jan , Johansson Ingegerd , Hillman Jan 
Published: May 2009

Object. Transportation of unstable neurosurgical patients involves risks that may lead to further deterioration and secondary brain injury from perturbations in physiological parameters. Mobile computerized tomography (CT) head scanning in the neurosurgery intensive care (NICU) is a new technique that minimizes the need to transport unstable patients. The authors have been using this device since June 1997 and have developed their own method of scanning such patients.Methods. The scanning procedure and radiation safety measures are described. The complications that occurred in 89 patients during transportation and conventional head CT scanning at the Department of Radiology were studied prospectively. These complications were compared with the ones that occurred during mobile CT scanning in 50 patients in the NICU. The duration of the procedures was recorded, and an estimation of the staff workload was made. Two patient groups, defined as high- and medium-risk cases, were studied. Medical and/or technical complications occurred during conventional CT scanning in 25% and 20% of the patients in the high- and medium-risk groups, respectively. During mobile CT scanning complications occurred in 4.3% of the high-risk group and 0% of the medium-risk group. Mobile CT scanning also took significantly less time, and the estimated personnel cost was reduced.Conclusions. Mobile CT scanning in the NICU is safe. It minimizes the risk of physiological deterioration and technical mishaps linked to intrahospital transport, which may aggravate secondary brain injury. The time that patients have to remain outside the controlled environment of the NICU is minimized, and the staff's workload is decreased.