National Hospital Organization Murayama Medical Center

Tokyo, Japan

National Hospital Organization Murayama Medical Center

Tokyo, Japan
Time filter
Source Type

Aihara T.,ATR Computational Neuroscience Laboratories | Takeda Y.,ATR Neural Information Analysis Laboratories | Takeda K.,ATR Computational Neuroscience Laboratories | Takeda K.,National Hospital Organization Murayama Medical Center | And 10 more authors.
NeuroImage | Year: 2012

Previous simulation and experimental studies have demonstrated that the application of Variational Bayesian Multimodal EncephaloGraphy (VBMEG) to magnetoencephalography (MEG) data can be used to estimate cortical currents with high spatio-temporal resolution, by incorporating functional magnetic resonance imaging (fMRI) activity as a hierarchical prior. However, the use of combined MEG and fMRI is restricted by the high costs involved, a lack of portability and high sensitivity to body-motion artifacts. One possible solution for overcoming these limitations is to use a combination of electroencephalography (EEG) and near-infrared spectroscopy (NIRS). This study therefore aimed to extend the possible applications of VBMEG to include EEG data with NIRS activity as a hierarchical prior. Using computer simulations and real experimental data, we evaluated the performance of VBMEG applied to EEG data under different conditions, including different numbers of EEG sensors and different prior information. The results suggest that VBMEG with NIRS prior performs well, even with as few as 19 EEG sensors. These findings indicate the potential value of clinically applying VBMEG using a combination of EEG and NIRS. © 2011 Elsevier Inc..

Fujiyoshi K.,Keio University | Fujiyoshi K.,National Hospital Organization Murayama Medical Center | Hikishima K.,Keio University | Hikishima K.,Central Institute for Experimental AnimalsKanagawa | And 18 more authors.
Journal of Neuroscience | Year: 2016

White matter abnormalities in the CNS have been reported recently in various neurological and psychiatric disorders. Quantitation of non-Gaussianity for water diffusion by q-space diffusional MRI (QSI) renders biological diffusion barriers such as myelin sheaths; however, the time-consuming nature of this method hinders its clinical application. In the current study, we aimed to refine QSI protocols to enable their clinical application and to visualize myelin signals in a clinical setting. For this purpose, animal studies were first performed to optimize the acquisition protocol of a non-Gaussian QSI metric. The heat map of standardized kurtosis values derived from optimal QSI (myelin map) was then created. Histological validation of the myelin map was performed in myelin-deficient mice and in a nonhuman primate by monitoring its variation during demyelination and remyelination after chemical spinal cord injury. The results demonstrated that it was sensitive enough to depict dysmyelination, demyelination, and remyelination in animal models. Finally, its utility in clinical practice was assessed by a pilot clinical study in a selected group of patients with multiple sclerosis (MS). The human myelin map could be obtained within 10 min with a 3 T MR scanner. Use of the myelin map was practical for visualizing white matter and it sensitively detected reappearance of myelin signals after demyelination, possibly reflecting remyelination inMSpatients. Our results together suggest that the myelin map, a kurtosis-related heat map obtainable with time-saving QSI, may be a novel and clinically useful means of visualizing myelin in the human CNS. © 2016 the authors.

Palmesino E.,Institute Of Recherches Cliniques Of Montreal Ircm | Rousso D.L.,University of California at Los Angeles | Kao T.-J.,Institute Of Recherches Cliniques Of Montreal Ircm | Klar A.,Hebrew University of Jerusalem | And 6 more authors.
PLoS Biology | Year: 2010

Topographic neuronal maps arise as a consequence of axon trajectory choice correlated with the localisation of neuronal soma, but the identity of the pathways coordinating these processes is unknown. We addressed this question in the context of the myotopic map formed by limb muscles innervated by spinal lateral motor column (LMC) motor axons where the Eph receptor signals specifying growth cone trajectory are restricted by Foxp1 and Lhx1 transcription factors. We show that the localisation of LMC neuron cell bodies can be dissociated from axon trajectory choice by either the loss or gain of function of the Reelin signalling pathway. The response of LMC motor neurons to Reelin is gated by Foxp1- and Lhx1-mediated regulation of expression of the critical Reelin signalling intermediate Dab1. Together, these observations point to identical transcription factors that control motor axon guidance and soma migration and reveal the molecular hierarchy of myotopic organisation. © 2010 Palmesino et al.

Kobayashi Y.,Keio University | Okada Y.,Keio University | Itakura G.,Keio University | Iwai H.,Keio University | And 12 more authors.
PLoS ONE | Year: 2012

Murine and human iPSC-NS/PCs (induced pluripotent stem cell-derived neural stem/progenitor cells) promote functional recovery following transplantation into the injured spinal cord in rodents. However, for clinical applicability, it is critical to obtain proof of the concept regarding the efficacy of grafted human iPSC-NS/PCs (hiPSC-NS/PCs) for the repair of spinal cord injury (SCI) in a non-human primate model. This study used a pre-evaluated "safe" hiPSC-NS/PC clone and an adult common marmoset (Callithrix jacchus) model of contusive SCI. SCI was induced at the fifth cervical level (C5), followed by transplantation of hiPSC-NS/PCs at 9 days after injury. Behavioral analyses were performed from the time of the initial injury until 12 weeks after SCI. Grafted hiPSC-NS/PCs survived and differentiated into all three neural lineages. Furthermore, transplantation of hiPSC-NS/PCs enhanced axonal sparing/regrowth and angiogenesis, and prevented the demyelination after SCI compared with that in vehicle control animals. Notably, no tumor formation occurred for at least 12 weeks after transplantation. Quantitative RT-PCR showed that mRNA expression levels of human neurotrophic factors were significantly higher in cultured hiPSC-NS/PCs than in human dermal fibroblasts (hDFs). Finally, behavioral tests showed that hiPSC-NS/PCs promoted functional recovery after SCI in the common marmoset. Taken together, these results indicate that pre-evaluated safe hiPSC-NS/PCs are a potential source of cells for the treatment of SCI in the clinic. © 2012 Kobayashi et al.

Yagi M.,National Hospital Organization Murayama Medical Center | Rahm M.,Scott and White Clinic | Gaines R.,Columbia Spine Center and Orthopaedic Group | Maziad A.,Hospital for Special Surgery | And 4 more authors.
Spine | Year: 2014

STUDY DESIGN.: Retrospective case series of surgically treated patients with adult spine deformity (ASD). OBJECTIVE.: To report the incidence of proximal junctional failure (PJF), characterize PJF and evaluate the outcome of revision surgery for PJF. A modified classification is also proposed. SUMMARY OF BACKGROUND DATA.: Although recent reports have shown the catastrophic results of PJF, few reports have shown the incidence, characteristics, and clinical outcomes of PJF in ASD. METHODS.: This retrospective analysis reviewed data entered prospectively into a multicenter database. Surgically treated patients with ASD with a minimum 2-year follow-up were included. PJF was defined as any type of symptomatic proximal junctional kyphosis (PJK) requiring surgery. On the basis of our previous classification, the following modified PJK classification was established: grade A, proximal junctional increase of 10° to 19°; grade B, 20° to 29°; and grade C, 30° or more. Three types of PJK were also defined: ligamentous failure (type 1), bone failure (type 2), and implant/bone interface failure (type 3). An additional criterion was added for the presence or absence of spondylolisthesis above the upper instrumentation vertebra (UIV). RESULTS.: PJF developed in 23 of the 1668 patients with ASD. The incidence of PJF was 1.4%. The mean age was 62.3 ± 7.9 years, and the mean follow-up was 4.0 ± 2.3 years. Seventeen patients had undergone prior surgical procedures. Six patients had UIV above T8, and 17 had UIV below T9. Six patients had associated spondylolisthesis above the UIV (PJF-S), whereas 17 patients did not (PJF-N). The radiographical data show a significant difference in the preoperative sagittal vertical axis between the PJF-S and PJF-N groups, whereas no significant difference was observed in the preoperative sagittal parameters (5.2 ± 3.9 cm vs. 11.4 ± 6.0 cm, P = 0.04). The most common type of PJF was type 2N. The PJF symptoms consisted of intolerable pain (n = 17), neurological deficits (n = 6), and progressive trunk deformity (n = 1). Eleven patients had additional PJK/PJF and 9 required additional revision surgical procedures. CONCLUSION.: The incidence of PJF among surgically treated patients with ASD was 1.4%. The most common type of PJF was 2N. Preoperative large sagittal vertical axis change and large amount of correction was a causative factor for spondylolisthesis above the UIV. After the revision surgery, further PJF was a commonly occurred event. Copyright © 2014 Lippincott Williams & Wilkins.

Pokorski M.,National Hospital Organization Murayama Medical Center | Pokorski M.,Polish Academy of Sciences | Takeda K.,National Hospital Organization Murayama Medical Center | Sato Y.,Tokushima University | Okada Y.,National Hospital Organization Murayama Medical Center
Acta Physiologica | Year: 2014

Aim: Recently, TRPA1 channels, richly expressed in both peripheral and central neural systems, have been proposed as novel sensors of changes in oxygen concentration along the hypoxic-hyperoxic continuum. In this study, we investigated the hypothesis that TRPA1 channels blockade should profoundly affect the hypoxic ventilatory response (HVR). Methods: We examined the chemosensory ventilatory responses in conscious mice before and after intraperitoneal administration of the specific TRPA1 antagonist HC-030031 in two doses of 50 and 200 (cumulative dose 250) mg kg-1. Ventilation and its responses to mild 13% and severe 7% hypoxia, pure O2, and 5% CO2 in O2 were recorded in a whole-body plethysmograph. Results: TRPA1 antagonism caused a dose-dependent attenuation of the HVR. Ventilatory stimulation was virtually abrogated in response to the mild, but it remained viable, albeit slashed, at severe hypoxia after the bigger dose of HC-030031. The TRPA1 function seemed specific for the hypoxic chemoreflex as neither the response to pure O2 nor hypercapnia was appreciably influenced by the TRPA1 antagonist. Conclusions: The study unravelled the role of TRPA1 in shaping the ventilatory response to low-intensity hypoxia, liable to be mediated by vagally innervated respiratory chemosensors of lower functional rank, but contradicted the TRPA1 being indispensable for the powerful carotid body chemoreflex in face of a severe hypoxic threat. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Yagi M.,Hospital for Special Surgery | Yagi M.,National Hospital Organization Murayama Medical Center | Patel R.,Hospital for Special Surgery | Boachie-Adjei O.,Hospital for Special Surgery
Journal of Spinal Disorders and Techniques | Year: 2015

Background Context: Combined anterior/posterior (A/P) spinal fusion with instrumentation has been used for many years in the treatment of adult thoracolumbar and lumbar (TL/L) scoliosis. However, the risk factors for complications and poor clinical outcomes with this procedure are not well known. Purpose: To assess the risk factors for poor clinical outcomes in a series of adult lumbar or scoliosis patients undergoing combined A/P-instrumented spinal fusion. Study Design: This study was a retrospective case series of surgically treated adult lumbar or thoracolumbar scoliosis patients. Patient Sample: From 1998 to 2006, 57 patients with diagnoses of adult idiopathic scoliosis or degenerative TL/L scoliosis underwent combined A/P spinal instrumentation and fusion at 1 institution, performed by 1 senior author. Outcome Measurements: The preoperative and postoperative outcome measurements included self-report measurements, physiological measurements, and functional measurements. Materials and Methods: A retrospective review of this patient group was performed to evaluate patient satisfaction, functional outcomes, pain, curve progression, and complications. Radiographic measurements included coronal balance, sagittal vertical axis, Cobb angle, thoracic kyphosis, lumbar lordosis, and pelvic incidence preoperatively, immediately postoperatively, and during follow-up. In terms of risk factors, bone mineral density, body mass index, age, kyphosis, and fusion to the sacrum were reviewed. Postoperative Scoliosis Research Society Patient Questionnaire outcome scores, Oswestry Disability Index (ODI), and anterior surgical site pain (ASSP) were also evaluated. Means were compared with the Student t test and the χ2 test. Logistic regression analyses were used to predict the probabilities and the odds ratios (ORs) of the risk factors for poor clinical outcomes. A P-value of <0.05 with a confidence interval of 95% was considered significant. Results: Fifty patients had adult idiopathic scoliosis, and 7 patients had degenerative scoliosis. The average age at surgery was 53.8 years (34-74 y), and the average follow-up was 4.8 years (2-11 y). Coronal correction for thoracic, thoracolumbar, and lumbosacral curves improved significantly. The degree of sagittal curve and coronal and sagittal balance were not significantly changed after surgery or at the final follow-up. ODI, the pain intensity domain of the ODI, and ASSP were significantly worse in obese and overweight patients, whereas OR time, estimated blood loss, and number of fused vertebrae were not different in the entire group (P=0.03 for ODI, P=0.002 for pain domain of ODI, and P=0.003 for ASSP). Logistic regression analyses for the risk factors of poor clinical outcomes indicated obesity and overweight as risk factors for poor clinical outcomes (OR=6.25 for ODI and 5.88 for ODI pain intensity score). A significantly higher rate of major complications occurred in this group compared to the entire group (30.4%, P=0.04). Low bone mineral density, old age, kyphosis, and fusion to the sacrum were not risk factors for poor clinical outcomes. Conclusions: Despite the good function scores and acceptable pain levels in most patients, the ODI scores of obese and overweight patients were worse compared to the rest of the patients in this study. Significantly worse scores on the pain intensity domain of the ODI and ASSP differences were likely caused by extensive dissection of the abdominal wall and psoas muscles and the technical difficulty of achieving an anterior approach to the thoracolumbar spine. Radiographs revealed no progression of the TL/L curves. This study indicates that obesity and overweight are potential risk factors for combined A/P-instrumented spinal fusion in patients with adult TL/L scoliosis, perhaps due to the technical difficulty of achieving an anterior approach to the thoracolumbar spine. Copyright © 2013 Wolters Kluwer Health, Inc. All rights reserved.

Yagi M.,National Hospital Organization Murayama Medical Center | King A.B.,Hospital for Special Surgery | Boachie-Adjei O.,Hospital for Special Surgery
Spine | Year: 2012

STUDY DESIGN. A retrospective case series of surgically treated patients with adult scoliosis. OBJECTIVE. The purpose of this study was to evaluate the incidence, risk factors, and natural course of proximal junctional kyphosis (PJK) in a long-term follow-up of patients with adult idiopathic scoliosis undergoing long instrumented spinal fusion. SUMMARY OF BACKGROUND DATA. Although recent reports have showed the prevalence, clinical outcomes, and the possible risk factors of PJK, quite a few reports have showed long-term follow-up outcome. MATERIALS AND METHODS. This is a retrospective review of the charts and radiographs of 76 consecutive patients with adult scoliosis treated with long instrumented spinal fusion. Radiographical measurements and demographic data were reviewed on preoperation, immediate postoperation, 2 years postoperation, 5 years postoperation, and at follow-up. Postoperative Scoliosis Research Society scores and Oswestry Disability Index were also evaluated. Means were compared with Student t test. A P value of less than 0.05 with 95% confidence interval was considered significant. RESULTS. The mean age was 48.8 years (range, 23-75 yr) and the average follow-up was 7.3 years (range, 5-14 yr). PJK has been identified in 17 patients. The Scoliosis Research Society and Oswestry Disability Index did not demonstrate significant differences between PJK group and non-PJK group; 2 patients had additional surgeries performed for local pain. Seventy-six percent of PJK has been identified within 3 months after surgery. Despite the fact that 53% of total degree of PJK was progressed within 3 months after surgery, PJK continuously progressed to the final follow-up. Pre-existing low bone mineral density, posterior spinal fusion (PSF), fusion to sacrum, inappropriate global spine alignment, and greater sagittal vertical axis change were identified as significant risk factors for PJK (P = 0.04, P < 0.001, P = 0.02, P < 0.0001, and P = 0.01). CONCLUSION. In a long-term review of minimum 5 years, 76% of PJK occurred within 3 months after surgery. Pre-existing low bone mineral density, PSF, fusion to the sacrum, inappropriate global spine alignment, and greater sagittal vertical axis change were significant risk factors for PJK. Careful long-term follow-up should be done for a patient with PJK. © 2012, Lippincott Williams &Wilkins.

Yagi M.,National Hospital Organization Murayama Medical Center | Takeda K.,National Hospital Organization Murayama Medical Center | Takeda K.,Mie University | Machida M.,National Hospital Organization Murayama Medical Center | Asazuma T.,National Hospital Organization Murayama Medical Center
Spine Journal | Year: 2015

Background context During quiet standing, the gravity line (GL) can be located according to the sum of the ground reaction forces (GRFs) measured with a force platform. C7 plumb line (C7PL) is an easy method to estimate sagittal trunk balance, but discordance between C7PL and the GL is widely recognized. However, the prevalence of occiput-trunk (O-T) discordance (GL-C7PL>3 cm) and the factors affecting this type of discordance have not yet been determined. Purpose The purpose of this study was to report the prevalence of O-T discordance in adult spinal deformity (ASD) patients and identify the factors affecting this type of discordance. Study design This was a retrospective consecutive case series of ASD. Patient sample This retrospective case series included 300 consecutive ASD patients. The inclusion criteria were age more than 50 years, Cobb angle of the main curve more than 20°, and C7PL more than 5 cm. The exclusion criteria consisted of inappropriate radiography; syndromic, neuromuscular, or other pathologic conditions; and previous joint replacement. Outcome measures The outcome measures included self-reported (Scoliosis Research Society 22 and Oswestry disability index [ODI]) and radiographic measures. Methods In a retrospective consecutive case series, demographic and radiographic patient data were reviewed. Demographic data included age, gender, curve type, SRS22, and ODI. Radiographic data included GL, C7PL, C2-C7, T2-T5, T5-T12, T10-L2, T2 tilt, lumbar lordosis (LL), sacrum slope (SS), pelvic tilt (PT), and pelvic incidence (PI). Global sagittal and spinopelvic alignments were also reviewed. Patients were categorized in either a O-T concordance (C group, GL-C7PL<3 cm) or a O-T discordance (D group, GL-C7PL more than +3 cm) group, and the demographic, radiographic, and clinical outcome data were compared between these groups. One-way analysis of variance, correlation coefficient tests, and multiple regression and logistic regression analyses were performed for statistical analysis. p Value less than.01 was considered statistically significant. Force platform analysis was performed to assess the relationship among GRF, GL, and C7PL. Results Among 300 consecutive ASD patients, 72 (24%) were categorized in the D group. There was no significant difference in terms of demographic data between the C and D groups. The SRS and ODI of patients with GL more than 10 cm were significantly lower than those of patients with GL less than 10 cm. Comparisons of regional sagittal alignment showed significantly higher T5-T12 values in the D group, and multiple regression analysis revealed significant correlations among T2-T5, T5-T12, and GL-C7PL. In contrast, the analysis of global sagittal alignment revealed a significantly large T2 sagittal tilt in the D group compared with the C group. Force platform analysis showed concordance between GRF and GL, whereas discordance was observed between GRF and C7PL. The D group could be classified into 2 groups based on the global sagittal alignment: 10 patients were classified as the hypo-compensation type (small SVA, small CL, small TK, and normal-to-small LL), whereas 62 were classified as the forward-leaning type (large sagittal vertical axis, large cervical lordosis, large thoracic kyphosis, and small LL). Conclusions The prevalence of discordance between GL and C7PL in ASD patients was 24%, and thoracic kyphosis and global sagittal alignment were significantly correlated with this discordance. The concordance of GRF and GL and the discordance of GRF and C7PL highlight the importance and necessity of accounting for GL when considering surgical treatment. © 2015 Elsevier Inc. All rights reserved.

Sato S.,National Hospital Organization Murayama Medical Center | Yagi M.,National Hospital Organization Murayama Medical Center | Machida M.,National Hospital Organization Murayama Medical Center | Yasuda A.,National Hospital Organization Murayama Medical Center | And 7 more authors.
Spine Journal | Year: 2015

Background context: The favorable outcome of surgical treatment for degenerative lumbar spondylolisthesis (DS) is widely recognized, but some patients require reoperation because of complications, such as pseudoarthrosis, persistent pain, infection, and progressive degenerative changes. Among these changes, adjacent segmental disease (ASD) and same segmental disease (SSD) are common reasons for reoperation. However, the relative risks of the various factors and their interactions are unclear. Purpose: The purpose of this study was to determine the longitudinal reoperation rate after surgery for DS and to assess the incidence and independent risk factors for ASD and SSD. Study design: This study is a retrospective consecutive case series of patients with DS who were surgically treated. Patient sample: We assessed 163 consecutive patients who were surgically treated for DS between 2003 and 2008. Individual patients were followed for at least 5 years after the initial surgery. Outcome measures: The primary end point was any type of second lumbar surgery. Radiographic measurements and demographic data were reviewed. We compared patients who underwent reoperation with those who did not. Logistic regression analysis was used to determine the relative risk of ASD and SSD in patients surgically treated for DS. Methods: Radiographic measurements and demographic data were reviewed. We identified the incidence and risk factors for reoperation, and we performed univariate and multivariate analyses to determine the independent risk factors for revision surgery for SSD and for ASD as the two distinct reasons for the reoperation. Age, gender, etiology, body mass index (BMI), and other radiographic data were analyzed to determine the risk factors for developing SSD and ASD. Results: The average patient age was 65.8 (50-81 years; 73 women and 90 men; mean follow-up, 5.9±1.6 years). Eighty-nine patients had posterior lumbar interbody fusion and 74 had laminotomies. Twenty-two patients had L3-L4 involvement and 141 had L4-L5 involvement. The cumulative reoperation rate was 6.1% at 1 year, 8.5% at 2 years, 15.2% at 3 years, 17.7% at 5 years, and 23.3% (38/163 patients) at the final follow-up. A significantly higher reoperation rate was observed for patients undergoing laminotomy than for patients undergoing posterior lumbar interbody fusion (33.8% vs. 14.4%, p=.01). Eighteen patients (11.0%) had SSD, and 13 patients (8.9%) developed ASD. Higher BMI (obesity) and greater disc height (greater than 10 mm) predicted the occurrence of SSD in the multivariate model (BMI=odds ratio 4.11 [95% confidence interval 1.29-13.11], p=.016; disc height=3.18 [1.03-9.82], p=.044), and gender (male) and facet degeneration (Fujiwara grade greater than 3) predicted the development of ASD in the multivariate model (gender=4.74 [1.09-20.45], p=.037; facet degeneration=6.31 [1.09-36.52], p=.039). Conclusions: The incidence of reoperation in patients surgically treated for DS was 23.2% at a mean time of 5.9 years. A significantly higher incidence of reoperation was observed in patients treated with decompression alone compared with those treated with decompression and fusion. Body mass index and disc height were identified as independent risk factors for SSD, whereas male gender and facet degeneration were identified as independent risk factors for ASD. The results of this comprehensive review will guide spine surgeons in their preoperative planning and in the surgical management of patients with DS, thereby reducing the reoperation rate. © 2015 Elsevier Inc. All rights reserved.

Loading National Hospital Organization Murayama Medical Center collaborators
Loading National Hospital Organization Murayama Medical Center collaborators