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Abstract: Background: Conventional laminectomy is a simple procedure that provides adequate decompression in cases of lumbar spinal canal stenosis. However, with this surgical modality, important posterior osteoligamentous elements necessary for spinal stability are lost; and it is often accompanied by damage to the facet joint. Bilateral interlaminar fenestration and unroofing of the intervertebral foramen to achieve decompression of the nerve roots by using a unilateral microsurgical approach in lumbar spinal canal stenosis are less invasive compared with conventional laminectomy. Methods: We carried out bilateral interlaminar fenestration and unroofing of the intervertebral foramen to decompress the stenosed nerve roots under a microscope by using a unilateral approach. In particular, we performed the decompression of the contralateral nerve root with this surgical method by using a Caspar retractor. Surgery was performed on 47 patients (18 women and 29 men; 29-85 years; median age, 62 years). All cases were with single-level lumbar spinal canal stenosis and bilateral radiculopathy. Results: The mean preoperative NCOS was 29.8 (range, 8-48). The mean NCOS after a postoperative period of 3 months was 79.9 (range, 32-100). After a postoperative period of 2 years, the mean NCOS increased to 83.2 (range, 32-100). The satisfaction measures indicated that the procedure was “very successful” in 45 cases, providing “almost complete relief”; “fairly successful” in one case, providing “a good deal of relief”; and “not very successful” in another case, affording “only a little relief.” Conclusions: This unilateral, minimally invasive decompression provided satisfactory results. [Copyright &y& Elsevier]

The synthetic aperture magnetometry (SAM) is a spatially selective beamformer, which transforms neuromagnetic signals into units of dipole moment on a per-voxel basis. We applied this technique to demonstrate the tomographic distribution of the power calculated from the spontaneous magnetoencephalogram (MEG) activities in a patient with a focal cerebral ischemia.The distribution of spontaneous MEG activity was affected by the changes in the regional cerebral blood flow (rCBF) and also by the presence of magnetic resonance image (MRI)-documented lesion. The present study for the first time demonstrated the altered patterns in the tomography of spontaneous MEG activity at different frequency bands, i.e. delta, alpha and beta bands, in a stroke patient which may elucidate an important implication in the pathoneurophysiology associated with cerebral ischemia. [Copyright &y& Elsevier]

Background: To examine the strength and tolerance of the fibrin glue sealant in a situation of extended transsphenoidal surgery. The withstand pressure of fibrin glue sealant was measured using a simple sellar reconstruction model. Methods: A 15-mm diameter hole at the bottom of a 51-cm high cylinder was covered with a Gore-Tex (Gore-Tex, Tokyo, Japan) sheet. A small plate was placed on the center for a brief fixation, and 3 mL of fibrin glue was applied over the entire bottom. Then water was gradually filled in five cylinders, and the water level at leakage was measured as withstand pressures at 10 minutes and 24 hours after sealant application. The stability of the sealant under pressures of 20 and 30 cm H2O for 12 hours was also examined. Results: The median initial withstand pressure at 10 minutes was 32 cm H2O (n = 5), and was significantly increased to 47.5 cm H2O after 24 hours (n = 4). In four of five cylinders, fibrin glue sealants were stable against a pressure of 20 cm H2O for 12 hours and 30 cm H2O for the next 12 hours. Conclusions: The withstand pressure of simple fibrin glue sealant without other biological reactions could be estimated to be more than 20 cm H2O after application, and increased to more than 40 cm H2O after 24hours. These data are practical for neurosurgeons to comprehend the strength and limit of fibrin glue sealant and suggests the importance to control the intracranial pressure to less than 20 cm H2O, especially for the first 12 to 24 hours. [ABSTRACT FROM AUTHOR]

We examined the effect of the pathology of Alzheimer's disease (AD) on improvement of clinical symptoms after shunt surgery in patients with idiopathic normal pressure hydrocephalus (iNPH). Forty-four iNPH patients were classified into 18 patients with (iNPH/AD +) and 26 patients without (iNPH/AD −) combination with low amyloid β42 and high total tau in cerebrospinal fluid (CSF). We compared improvements after lumbo-peritoneal shunt surgery (LPS) between the two groups in Timed Up & Go Test, 10-m reciprocating walking test, Digit Symbol Substitution Test, attention test, delayed recall test, Mini-Mental State Examination, iNPH grading scale, Neuropsychiatric Inventory, Zarit Burden Interview, and other evaluations. Three months after LPS, gait, urination, overall cognition, psychomotor speed, attention, and neuropsychiatric symptoms significantly improved in both groups, but the improvement in delayed recall and reduction of caregiver burden were significantly greater in iNPH/AD − than iNPH/AD +. In addition, improvement in delayed recall score after LPS was significantly and negatively correlated with the probability of AD as judged by amyloid β42 and total tau levels in CSF. Three months after LPS, almost all of the triad symptoms decreased in iNPH patients with and without AD pathology but memory improved only in iNPH patients without AD pathology. [ABSTRACT FROM AUTHOR]

Background When it comes to evacuating intracranial hemorrhagic lesions in patients with traumatic brain injury (TBI), neurosurgeons perform either a craniotomy or a decompressive craniectomy (DC). The aim of the present study was to estimate the impact of DC on outcomes in elderly patients. Methods This retrospective cohort study, conducted in a neurosurgical institute in Japan from April 2009 to June 2014, included 91 consecutive patients with TBI (aged 60 years or older) who underwent evacuation of intracranial hemorrhagic lesions. Patients were divided into 2 groups: craniotomy only or DC. We set the primary endpoint as an unfavorable outcome (death or vegetative state), as evaluated on the Glasgow Outcome Scale at 6 months after injury. The secondary endpoints included existence of delayed hemorrhage and occurrence of hydrocephalus requiring shunt placement. The inverse probability of treatment weighting method was used to develop a propensity model to adjust for baseline imbalances between groups. Results The DC group exhibited greater severity both in clinical and computed tomography findings according to baseline characteristics. After we adjusted for these differences by inverse probability of treatment weighting using the propensity score, DC was significantly associated with unfavorable outcomes (adjusted odds ratio, 8.00; 95% confidential interval, 2.30–27.84; P = 0.002) and delayed hemorrhage (adjusted odds ratio, 13.42; 95% confidential interval, 1.52–118.89; P = 0.022). There was no significant difference in the occurrence of hydrocephalus requiring shunt placement. Conclusions DC in conjunction with evacuation of intracranial hemorrhagic lesions was associated with worse functional outcome in elderly patients with TBI. [ABSTRACT FROM AUTHOR]

Introduction Patients with idiopathic normal pressure hydrocephalus (iNPH) have neuropsychiatric symptoms that could affect patients' quality of life and caregiver burden. In this study, we assessed the effect of lumbo-peritoneal (L-P) shunt surgery on neuropsychiatric symptoms and the association between neuropsychiatric symptoms and caregiver burden after L-P shunt surgery. Methods We recruited 22 iNPH patients who had L-P shunt surgery and who were followed up for 3 months after surgery. Neuropsychiatric symptoms and caregiver burden were evaluated with the Neuropsychiatric Inventory (NPI) and Zarit Burden Interview (ZBI), respectively, before and 3 months after surgery. We evaluated the changes of NPI and ZBI and the association between the changes in these 2 scores and the triad symptoms. Results NPI total, apathy, and depression scores significantly decreased after surgery. The improvement in NPI total, apathy, disinhibition, and irritability scores after surgery were significantly and positively associated with improvement in ZBI score after surgery. Improvement in NPI apathy score was significantly associated with improvement in Frontal Assessment Battery score after surgery. Conclusion L-P shunt surgery was effective in reducing not only the triad symptoms but also the neuropsychiatric symptoms, and the improved neuropsychiatric symptoms might decrease caregiver burden for iNPH patients. [ABSTRACT FROM AUTHOR]

Summary: To investigate involvement of extrafocal regions in mesial temporal lobe epilepsy (MTLE), we retrospectively explored abnormalities in distribution of iomazenil (IMZ) activity by identifying interhemispheric asymmetry on IMZ-SPECT images of patients with MTLE. Fourteen MTLE patients in whom a good surgical outcome was achieved were included in the study. Voxel-based (VB) analysis and volume-of-interest (VOI) analysis with predefined VOIs were applied to compare IMZ binding between the hemispheres ipsilateral and contralateral to the epileptic focus. VB analysis showed significant decreases in iomazenil binding not only in the ipsilateral anterior temporal lobe including the mesial temporal structures but also in the ipsilateral extratemporal region including the insula, putamen, and medial occipital lobe. VOI analysis showed similar significant decreases in the ipsilateral parahippocampal gyrus, amygdala, putamen, lateral temporal lobe, and lateral occipital lobe. Results of the SPECT analyses suggest that decreased or dysfunctional IMZ activity extends from the mesial temporal lobe to the ipsilateral extrafocal region in patients with MTLE. [Copyright &y& Elsevier]

Abstract: A brain machine interface (BMI) provides the possibility of controlling such external devices as prosthetic arms for patients with severe motor dysfunction using their own brain signals. However, there have been few studies investigating the decoding accuracy for multiclasses of useful unilateral upper limb movements using non-invasive measurements. We investigated the decoding accuracy for classifying three types of unilateral upper limb movements using single-trial magnetoencephalography (MEG) signals. Neuromagnetic activities were recorded in 9 healthy subjects performing 3 types of right upper limb movements: hand grasping, pinching, and elbow flexion. A support vector machine was used to classify the single-trial MEG signals. The movement types were predicted with an average accuracy of 66±10% (chance level: 33.3%) using neuromagnetic activity during a 400-ms interval (−200ms to 200ms from movement onsets). To explore the time-dependency of the decoding accuracy, we also examined the time course of decoding accuracy in 50-ms sliding windows from −500ms to 500ms. Decoding accuracies significantly increased and peaked once before (50.1±4.9%) and twice after (58.5±7.5% and 64.4±7.6%) movement onsets in all subjects. Significant variability in the decoding features in the first peak was evident in the channels over the parietal area and in the second and third peaks in the channels over the sensorimotor area. Our results indicate that the three types of unilateral upper limb movement can be inferred with high accuracy by detecting differences in movement-related brain activity in the parietal and sensorimotor areas. [Copyright &y& Elsevier]

Abstract: Alpha rhythm is one of the most prominent electromagnetic changes in the brain, and electroencephalography (EEG) alpha reactivity disturbance may sometimes represent an early sign of cerebral dysfunction. Although magnetoencephalography (MEG) has a better spatial resolution than EEG, it has not extensively been used to explore alpha-power change deficits in schizophrenia as a possible neurophysiological marker of the disease. The purpose of this study was to use MEG to identify abnormalities in alpha synchronization induced by eye-closing in schizophrenia patients compared to healthy controls, and to investigate whether alpha reactivity deficits correlate with clinical features of the disorder. MEG data were recorded in 22 schizophrenia patients and 20 age- and gender-matched controls during eyes-open/eyes-closed resting states. Cortical sources of event-related synchronization (ERS) were estimated using multiple source beamformer, and BrainVoyager was used for statistic group analysis. A significant decrease in ERS in the upper alpha band (10–13Hz) was found in the left posterior temporal region in schizophrenia patients relative to controls, and this activity showed correlation with visual memory scores. This upper alpha ERS deficit may indicate left temporal dysfunction and visual-information processing impairment in schizophrenia, and upon further confirmation it might represent a neurophysiological state marker of the disorder. [Copyright &y& Elsevier]

Abstract: C-Jun N-terminal kinase (JNK) mediates neuronal death in response to stress and injury in the CNS and peripheral nervous system. Here, we show that JNK also regulates retrograde axonal degeneration (axonal dieback) after spinal cord injury (SCI) in mice. Activated phospho-JNK was highly expressed in damaged corticospinal tract (CST) axons after thoracic SCI by hemisection. Local administration of SP600125, a JNK inhibitor, prevented accumulation of amyloid-β precursor protein and retraction of the severed CST axons as well as preserved the axonal arbors rostral to the injury site. The treatment with SP600125 also improved functional recovery of the hindlimbs, assessed by Basso mouse scale open-field scores and the grid-walking test. In Jnk1 −/− and Jnk3 −/− mice, we observed prevention of axonal degeneration and enhancement of motor recovery after SCI. These results indicate that both JNK1 and JNK3 induce axonal degeneration and limit motor recovery after SCI. Thus, a JNK inhibitor may be a suitable therapeutic agent for SCI. [Copyright &y& Elsevier]

Abstract: Although recent studies have shown that cell transplantation is effective in promoting regeneration of the central nervous system (CNS) of adult mammals, functional recovery has been reported to be limited. In vitro models of axonal outgrowth assays are often used as easy methods for screening cells for transplantation but often fail to reflect the physiological conditions of in vivo CNS injury models. In order to bridge the gap between in vitro and in vivo models, we have established a new organotypic co-culture system comprising cortical tissue and a Matrigel containing several cell types that are candidates for transplantation therapy for CNS injury. In this model, cells transplanted in a Matrigel produce a three-dimensional architecture, with axons elongating from the cortex in the Matrigel. The ability of the transplanted cells to promote axonal growth was examined quantitatively by assessing axonal number and length. Moreover, we observed site-specific rearrangement of transplanted cells and interactions between axons and cells, including several cortical cells that migrated into the gel. These results indicate that our co-culture system can provide a useful assay for transplanted cells prior to in vivo screening. [Copyright &y& Elsevier]

Abstract: The mu rhythm is regarded as a physiological indicator of the human mirror neuron system (MNS). The dysfunctional MNS hypothesis in patients with autistic spectrum disorder (ASD) has often been tested using EEG and MEG, targeting mu rhythm suppression during action observation/execution, although with controversial results. We explored neural activity related to the MNS in patients with ASD, focusing on power increase in the beta frequency band after observation and execution of movements, known as post-movement beta rebound (PMBR). Multiple source beamformer (MSBF) and BrainVoyager QX were used for MEG source imaging and statistical group analysis, respectively. Seven patients with ASD and ten normal subjects participated in this study. During the MEG recordings, the subjects were asked to observe and later execute object-related hand actions performed by an experimenter. We found that both groups exhibited pronounced PMBR exceeding 20% when observing and executing actions with a similar topographic distribution of maximal activity. However, significantly reduced PMBR was found only during the observation condition in the patients relative to controls in cortical regions within the MNS, namely the sensorimotor area, premotor cortex and superior temporal gyrus. Reduced PMBR during the observation condition was also found in the medial prefrontal cortex. These results support the notion of a dysfunctional execution/observation matching system related to MNS impairment in patients with ASD, and the feasibility of using MEG to detect neural activity, in particular PMBR abnormalities, as an index of MNS dysfunction during performance of motor or cognitive tasks. [Copyright &y& Elsevier]

Abstract: Situs inversus totalis (SI) is a rare condition in which all visceral organs are arranged as mirror images of the usual pattern. The objective of this study was to determine whether SI individuals have reversed brain asymmetries. We performed a neuroimaging study on 3 SI subjects and 11 control individuals with normally arranged visceral organs. The language-dominant hemisphere was determined by magnetoencephalography. Left-hemispheric dominance was observed in 1 SI subject and all controls, whereas right-hemispheric dominance was observed in the remaining 2 SI subjects. Statistical analysis revealed that language dominance patterns in SI subjects were different from those in the controls, suggesting that the developmental mechanisms underlying visceral organ asymmetries are related to those underlying functional brain asymmetry. Anatomical brain asymmetries were determined by magnetic resonance imaging. SI subjects had the same planum temporale (PT) asymmetry pattern as the controls, but a reversed petalia asymmetry pattern. The inferior frontal gyrus (IFG) asymmetry pattern varied within both groups, indicating a relationship between the rightward IFG and right-hemispheric language dominance. These results suggest that the developmental mechanisms underlying visceral organ asymmetries are related to those underlying petalia asymmetry but not to those underlying PT and IFG asymmetries, and that brain asymmetries might develop via multiple region-dependent mechanisms. [Copyright &y& Elsevier]

Summary: Epileptic activities are known to be modulated by cortical excitability, which is altered with normal brain functioning such as movement. However, the relationship between the epileptic activity and movement has not been well studied. Here, we investigated movement-induced modulation of interictal spikes to reveal the relationship between epileptic activity and the movement-induced modulation of cortical activity. Two patients (three cases) with focal cortical dysplasia (FCD) of the pre- and/or post-central gyrus performed voluntary movements of their hands or mouths. During the movement, the interictal spikes of the sensorimotor cortex, which were measured by electrocorticograms (ECoG), were significantly reduced. This reduction strongly correlated with the event-related desynchronization (ERD) of the cortical oscillatory activity at the lower frequency bands (<25Hz) during movement. The epileptic activity was suggested to be modulated by the movement, which correlates with the ERD of the cortical oscillatory activity. [Copyright &y& Elsevier]

Abstract: Background: The role and timing of surgical decompression for SCI remains controversial, when the surgical outcomes are evaluated only by neurologic recovery. Other than neurologic deficits, severe pain after SCI is a significant problem, deteriorating the patient''s activity of daily living. In the present report, allodynia of patients'' upper limbs caused by cervical SCI was treated successfully by surgical decompression. Case Descriptions: Three male patients received cervical SCI through minor accidents. They complained of allodynia and motor dysfunction at the spinal level compressed by preexisting lower cervical spondylosis, but they lacked symptoms or neurologic abnormalities below that spinal level. Severe pain was induced by soft touch or exposure to water at room temperature preoperatively. Surgical decompressions of the spinal cord and nerve roots were performed between 20 and 83 days (mean, 48.7 days) after the SCI. Allodynia was reduced in all patients immediately after surgery. Pain induced by soft touch disappeared within 4 days of operations, whereas pain by water exposure diminished within months. Recurrence of allodynia has not been observed in patients at least until the last follow-up, within periods ranging from 15 to 39 months (average, 26 months). The mean preoperative VAS was 6.0, and this improved to 2.2 at 1 month and 0.8 at the final follow-up. Conclusion: We propose that patients with SCI with allodynia and motor dysfunction of the upper limbs related only to the compressed spinal levels are potentially treatable by surgical decompression. [Copyright &y& Elsevier]

Abstract: In patients with Alzheimer''s disease (AD), it is sometimes challenging to identify typical findings in electroencephalography (EEG) or magnetoencephalography (MEG) such as a slowing of the posterior dominant activity or an increase in slow activity. In this MEG study, we evaluated the event-related synchronization (ERS) of alpha activity after eye closing in patients with early AD and mild cognitive impairment (MCI) who presented no slow MEG pattern. Thirteen patients with probable AD and thirteen patients with MCI, who met NINCDS-ADRDA and Petersen''s diagnostic criteria, respectively, were enrolled. We also selected fourteen age-matched normal control subjects. MEG activity was acquired during eye-open and eye-closed states. The ERS after eye closing within 8–15Hz frequency band was calculated and its cortical source was superimposed on the individual''s MRI by using the beamformer implemented in Brain Electrical Source Analysis (BESA). The Source image was converted into a standardized image, and group comparisons across patients with AD, MCI and controls were performed using BrainVoyager QX. The averaged ERS was observed dominantly in posterior regions in all three groups. Significant difference in ERS was observed only for the comparison between AD patients and controls, with AD patients showing increased ERS in frontal regions. Frontal shift of posterior alpha activity was observed clearly in AD patients using the combination of beamformer and group comparison. [Copyright &y& Elsevier]

Abstract: Background: Empirical methods in postoperative wound care have been performed by individual neurosurgeons. We evaluated a hydrocolloid dressing for neurosurgical wounds according to the modern concept of wound healing. Methods: From May 2005 to March 2007, we performed 117 cranial neurosurgical procedures in consecutive 100 patients. Karayahesive® (ALCARE, Tokyo, Japan), a transparent hydrocolloid dressing, was affixed onto all wounds immediately postoperatively. Clinical evaluations were performed for wound healing, wound infection, and cost-effectiveness. Results: Excellent wound healing and cosmetic results were obtained in all patients. There was no incisional surgical site infection. Analysis of cost-effectiveness suggested Karayahesive® as superior to conventional gauze-and-tape dressings. Conclusion: Karayahesive® fits with the modern concept of wound healing and is a useful dressing for neurosurgical wounds. [Copyright &y& Elsevier]

Abstract: Objective: To assess the pain-relieving effects of motor cortex electrical stimulation (MCS) within the central sulcus and the predictive factors retrospectively. Methods: Thirty-four patients with intractable neuropathic pain underwent MCS; 19 patients had cerebral lesions, and 15 had non-cerebral lesions. In selected 12 patients, test electrodes were implanted within the central sulcus and on the precentral gyrus. Twelve patients received both MCS and repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex. Results: Pain reduction of ⩾50% was observed in 12 of 32 (36%) patients with ⩾12 months follow-ups (2 patients were excluded because of short follow-up). In 10 of the 12 patients who received test electrodes within the central sulcus and on the precentral gyrus, the optimal stimulation was MCS within the central sulcus. In 4 of these (40%) patients, positive effects were maintained at follow-ups. The pain reduction of rTMS significantly correlated with that of MCS during test stimulation. Conclusions: The test stimulation within the central sulcus was more effective than that of the precentral gyrus. In the selected patients, chronic stimulation within the central sulcus did not significantly improve long-term results. Significance: The present findings suggest that an intra-central sulcus is one of the favorable targets for MCS. [Copyright &y& Elsevier]

Abstract: Synthetic aperture magnetometry (SAM) was applied to investigate changes in the mechanism of cerebral motor control in patients with tumors around the central sulcus in relation to the clinical relevance. MEG records were made during a resting state and a repetitive hand grasping task in patients with brain tumors around the central sulcus and in four control subjects. Topographic appearance of abnormal focal slowing in the delta, theta, and alpha bands (N =10) and event related desynchronizations (ERD) in the alpha, beta, and low gamma bands during the motor tasks (N =6) were analyzed statistically with SAM in relation to clinical signs and symptoms. Distribution of enhanced focal delta activity coincident with the motor cortices responsible for weakness. Volumetric analysis revealed emergence of tumor-related focal delta activity was greater for intra-axial tumors involving subcortical fibers than for other extra-axial tumors. In addition, patients with increased volume of enhanced delta activity exhibited poor functional recovery in the early post-operative period. Beta ERD in patients during affected side hand movement was also localized exclusively to the ipsilateral hemisphere contrary to the normal pattern. The characteristic focal delta distribution and the altered patterns of ERD in the patient group suggest not only close relation of cortical function and existing pathology but recruitment of diverse motor areas which may be required for the effective movement of the affected side. [Copyright &y& Elsevier]

Abstract: Cerebral occlusive vascular disease has been well investigated in aspect of a risk factor for stroke, however, whether it causes any alteration in brain function is poorly understood. To investigate this, we examined the motor related magnetic field in 20 patients with cerebral occlusive disease (12 with atherosclerotic (AS group) and 8 with non-atherosclerotic lesions (NAS group)) and 7 control subjects, and evaluated the spatial distribution and the intensity (t-value) of event related desynchronization in beta band during hand grasping and finger tapping tasks using synthetic aperture magnetometry. According to the laterality index (L.I.) calculated from peak t-values on both hemispheres, activation pattern was classified into 3 types, as contralateral—(L.I.>0), bilateral—(0.1

Abstract: The aim of this study is to reveal the oscillatory change and subjective arousal level during simulated driving using synthetic aperture magnetometry (SAM). Subjects were instructed to perform the driving simulation task using a steering wheel, accelerator and brake pedals. The subjective arousal level was estimated using a visual analog scale. The subjective arousal level was reduced and the activities of theta band (4–8 Hz) in frontal areas were increased as driving time advanced. It is well known that the theta wave increases during rest state. Our previous studies also demonstrated that pseudo-Z value in the theta band inversely correlates with subjective arousal level. The present study demonstrated that this relation holds true even during driving state. [Copyright &y& Elsevier]

Abstract: Background: Although craniopharyngiomas have a histologically benign nature, their treatment can be difficult. The correlation among clinical, proliferative, and immunohistologic features of female sex hormone receptors was determined in craniopharyngiomas to analyze whether they influence the growth of the tumor. Methods: The study subjects were 43 patients with previously untreated craniopharyngioma who underwent surgery at our department over the past 15 years. Serial tissue sections were immunostained with the antibodies against estrogen receptor (ER), progesterone receptor (PR), and Ki-67. Results: The Ki-67 labeling index was significantly higher in patients with regrowth (7.8%) than without regrowth (3.9%). ER and PR were detected in 9 of 30 (30%) craniopharyngiomas, and the incidence of postoperative tumor regrowth was significantly higher in patients negative for ER and PR (29%) than in those positive for both receptors (11%). Conclusions: A high Ki-67 labeling index suggests a high possibility of tumor regrowth, and the presence of ER and PR is suggestive of a high tissue differentiating potential. ER and PR assay may be useful for determining the indication for additional radiation therapy in craniopharyngioma patients treated by incomplete resection. [Copyright &y& Elsevier]

We examined transient neural activations from the input of a stimulus to the output of a response during the Stroop task for schizophrenic subjects with/without auditory hallucinations using a spatial filtered technique, synthetic aperture magnetometry (SAM), which provides high temporal and spatial resolution. MEG signals from the presentation of incongruent stimuli to responses were analyzed with a time window of 200 ms in steps of 50 ms. According to our previous studies with healthy subjects, regions showing significant decrease of current source density (CSD) in the 25–60-Hz band, corresponding to event-related desynchronization, were regarded to be activated. The non-hallucinators showed neural activations in the inferior parietal or temporal regions in the early stage of information processing, and successive and temporally overlapping neural activations in the left dorsolateral prefrontal cortex (DLPFC) and primary motor area (M1). The hallucinators showed neural activations in the right DLPFC and M1. Our preliminary results suggest that the schizophrenic subjects showed transient neural activations along the fundamental information flow (sensory input system–executive control system–motor output system), and that lateralization of DLPFC might be related with auditory hallucinations in schizophrenia. [Copyright &y& Elsevier]

Mu rhythm is the alpha (8–15 Hz) band oscillatory activity recorded over the sensorimotor cortex accompanied by a higher frequency band activity like beta (15–30 Hz) band. The contralateral sensorimotor area shows event-related desynchronization (ERD) of mu rhythm during limb movement and event-related synchronization (ERS) after the termination of the movement. Previous studies reported that ERD/ERS of mu and beta rhythm were detected during movement observation in the absence of physical movement, as well as during movement execution, suggesting that further investigations into the ERD/ERS of mu and beta rhythm in movement observation may elucidate the mechanisms of the mirror neuron system. We examined the post-movement ERS in beta band after movement observation by using MEG and Synthetic Aperture Magnetometry (SAM) analysis. The post-movement beta ERS was estimated over the bilateral, primary, sensorimotor area after the movement execution in all subjects, and estimated over the contralateral, primary, sensorimotor area after movement observation in four out of six subjects. Our results suggest that MEG SAM analysis is useful for the investigation of the mirror neuron system, which can be applied to clinical research for neurological and psychiatric diseases. [Copyright &y& Elsevier]

There is a Japanese traditional word game, “shiritori” (capping verses), analogous to English word generation. “Shiritori” task is characterized by demanding a subject to detect the phonetic factor of words as well as to generate words, and is expected to activate brain regions related to phonological processing, such as Wernicke''s area. The aim of this study is to visualize neural activated brain regions during performance of a “shiritori” task using a MEG neuroimaging technique, Synthetic Aperture Magnetometry (SAM). Eight healthy right-handed, native Japanese speakers were studied. They gave their informed consents. Subjects were instructed to play “shiritori” by themselves silently during the “shiritori” task. In 8–25 Hz band, neural activated regions (corresponding to event-related desynchronization) were estimated in language-related brain regions with left-side dominancy: dorsolateral prefrontal cortex (DLPFC), post-inferior frontal gyrus (IFG), primary motor cortex, post-superior temporal gyrus (STG), visual cortex, inferior parietal lobule. The results suggest that the “shiritori” task requires neural activations in Wernicke''s area more strongly when compared with verbal fluency paradigm and that this task can be used for assessing pathophysiology of diseases with dysfunction of Wernicke''s area such as schizophrenia. [Copyright &y& Elsevier]

To create a cell line with controlled and specific secretion of β-endorphin, a new fusion gene was constructed by joining human β-endorphin coding sequence to part of NL1 gene. HEK293 cells carrying Tet-on system transfected with this fusion gene secreted β-endorphin in a dose-dependent manner upon doxycycline administration. These findings suggest that this system can direct the controlled secretion of any peptide hormones such as β-endorphin. [Copyright &y& Elsevier]

: BackgroundExtra-axial primary CNS lymphoma, considered rare, mainly arise in the white matter of the brain. Though the tumor responds well to radiation and chemotherapy, the prognosis of primary CNS lymphoma remains poor. We report a case of primary lymphoma of Meckel’s cave mimicking a trigeminal schwannoma radiographically, which achieved complete remission through use of rapid high-dose MTX therapy and radiation therapy.: Case presentationThe patient, a 55-year-old Japanese male, presented left trigeminal neuralgia. Magnetic resonance imaging (MRI) revealed a mass lesion in the left side of Meckel’s cave, with extension into the cerebellopontine angle and the infratemporal fossa through the foramen ovale, suggesting trigeminal schwannoma. However, the patient suffered radiologically inexplicable progressive cranial nerve palsy, which suggested malignant disease. MRI and CSF disclosed malignant tumor dissemination; biopsy revealed malignant lymphoma. The treatment, composed of the rapid infusion of high-dose MTX and whole brain and spine radiation, resulted in complete remission.: ConclusionThis case, which included atypical presentation of malignant lymphoma, illustrates the importance of including malignant lymphoma in the differential diagnosis of CP-angle and Meckel’s cave tumor. The results also confirmed the usefulness of combined rapid high-dose MTX therapy and radiation. [Copyright &y& Elsevier]

Transcription factor nuclear factor-kappa B (NF-κB) is a principal mediator of response after ischemia/reperfusion in the brain and spinal cord. Decoy oligodeoxynucleotides (ODNs) for NF-κB attenuate the activation of genes, which mediate ischemic injury. The purpose of the present study was to investigate the effect of NF-κB decoy ODNs on the spinal cord ischemia (SCI) using a rat spinal cord ischemia/reperfusion injury model. During 10 min of spinal cord ischemia, hemagglutinating virus of Japan (HVJ)-liposome complex with NF-κB decoy ODNs was injected to the descending aorta. The transfection of NF-κB decoy ODNs was successful and the area of infarction was also significantly reduced by administration of NF-κB decoy ODNs 7 days after the reperfusion. The induction of target genes of NF-κB was significantly reduced by the administration of NF-κB decoy. These data suggested that NF-κB decoy ODNs might be a useful therapeutic tool for ischemia/reperfusion injury of the spinal cord. [Copyright &y& Elsevier]

The aim of this study was to verify the relation between gamma-band activity and process of function words. We recorded the neuromagnetic signals in six healthy volunteers during silent reading of verbs (verb task) and forming of the past tenses (past-tense task) and investigated the spatio-temporal distribution of event-related desynchronization (ERD) and synchronization using synthetic aperture magnetometry. In both tasks, ERDs were observed simultaneously at multiple language-related areas. The left junctional area of inferior frontal sulcus and precentral sulcus and the left supramarginal gyrus showed stronger and/or longer-lasting ERDs in past-tense task than in verb task. This result suggests that the gamma-activities reflect the syntactic process of words. [Copyright &y& Elsevier]

Parallel distributed processing neuroimaging in the Stroop color word interference task in five healthy subjects was studied. The total reaction time was set at 650 ms with a time window of 200 ms in steps of 50 ms. Spatially filtered magnetoencephalography analysis, as used in synthetic aperture magnetometry, was used. Neural activation began in the left posterior parietal-occipital area (150–250 ms post-stimulus), followed by the right prefrontal polar area (250–350 ms), the left dorsolateral prefrontal cortex (250–400 ms), and the mid- to lower- primary motor area (350–400 ms). Successive and temporally overlapping activation of various cortical regions were successfully estimated within a short 200 ms time interval, contrary to previous positron emission tomography and fMRI studies. [Copyright &y& Elsevier]

Controlled release of a water-soluble low-molecular-weight drug from silicone and its usefulness as a local therapeutic drug were studied. For application to ganciclovir/helpes simplex virus thymidine kinase (GCV/HSV-tk) suicide gene therapy for brain tumor, two kinds of GCV-containing silicone formulations were prepared for evaluation. In vitro, GCV release from matrix-type formulation consisting of a single matrix was characterized by Fickian diffusion, while covered-rod-type formulation, in which the side surface of the outer layer was covered with 100% silicone, exhibited a near-zero-order release pattern. In an in vivo study using a rat 9L glioblastoma model, administration of GCV-silicone formulation into brain tumor yielded sustained intracerebral GCV concentration for 4 days after administration, with excellent antitumor effect equal to or better than that of daily intraperitoneal administration of aqueous solution of GCV, at a dose less than 1/100 of the total dose of solution for intraperitoneal administration. Furthermore, GCV was undetectable in blood, suggesting that decrease in systemic adverse reactions can be expected with intracerebral administration of GCV-silicone formulation. [Copyright &y& Elsevier]

Using synthetic aperture magnetometry (SAM), we examined the spatial distribution of frequency changes in magnetoencephalography signal rhythms on individual magnetic resonance images following somatosensory stimulation. SAM is a novel statistical spatial filtering method that uses an adaptive beamformer. Electrical stimulation of the right median nerve demonstrated high-frequency event-related synchronization (ERS) in the 50–200-Hz range, consistently localized in the contralateral primary sensorimotor area in all subjects (n=7). Event-related desynchronization (ERD) was demonstrated in the 8–13, 13–25 and 25–50-Hz ranges bilaterally in the area surrounding the central sulcus. The differences in the spatial distribution as well as the frequency bands between ERS and ERD suggest that ERS and ERD reflect the responses of different cell assemblies rather than a frequency shift of the same cell assembly. [Copyright &y& Elsevier]

Abstract: Backgroud: Difficulty for distal exposure of the ICA is sometimes encountered during CEA. A carotid shunt is used to maintain sufficient cerebral blood flow during CEA but requires fixative materials, such as a string or a metallic ring, which often restrict the operative field, especially that of the distal ICA. Methods: Here, we describe a novel technique for carotid shunt fixation using a unique fixative device in CEA. In the method presented here, the carotid shunt is fixed with an inflated balloon and a conventional vascular tourniquet proximally, but distal fixation is achieved using a Sugita''s fenestrated clip that catches the mid portion of the carotid shunt and surrounding tissue. Results and Conclusion: The device prevents the distal carotid shunt slipping out of the distal ICA. The present method allows mobilization of the shunt position during CEA and facilitates far-distal exposure of the ICA. [Copyright &y& Elsevier]

Objectives Phantom limb pain is neuropathic pain after amputation of a limb and partial or complete deafferentation such as brachial plexus root avulsion. The underlying cause of this pain has been attributed to maladaptive plasticity of the sensorimotor cortex. It has been suggested that experimental reorganization would affect pain, especially if it results in functional restoration. We tested the hypothesis that restoration of hand motor function using a brain–machine interface (BMI) based on magnetoencephalographic (MEG) signals will normalize maladapted cortical representation and relieve pain. Methods This study included 10 phantom limb patients (9 brachial plexus root avulsion and 1 amputee). MEG signals during movements of the phantom hand or intact hand were used to train the decoder inferring movements of each hand. The robotic hand was controlled by the decoder. Patients controlled the robotic hand by moving the phantom hand. The training effects were compared among trainings with the phantom decoder, real hand decoder, and random decoder in a randomized cross-over trial. Results BMI training with the phantom decoder increased the decoding accuracy of phantom hand movements and pain. In contrast, BMI training with the intact hand decoder reduced accuracy and pain. Discussion It was suggested that BMI training to modulate the motor representation of phantom hand controlled pain. The sensorimotor cortical plasticity might induce pain. Conclusions and Significance Phantom limb pain was controlled by BMI training to induce sensorimotor cortical plasticity. [ABSTRACT FROM AUTHOR]

Background Vertebrobasilar artery entrapment resulting from a clivus fracture is rare. The entrapped lesions are not radiographically depicted precisely because they are only identified by autopsy or completely occluded. In addition, no changes in the features have been revealed clearly because radiologic examinations were performed only in the acute stage. Case Description We report a case of traumatic entrapment of the vertebral artery depicted precisely by a three-dimensional angiographic study in the subacute stage, presenting the serial changes in the morphologic features and a review of the published cases. Conclusion It is necessary to manage vertebrobasilar artery entrapment cautiously because it is suggested that the entrapped lesion is accompanied by arterial dissection. [ABSTRACT FROM AUTHOR]