Osamu Ikeda

Kashiwa City Hospital, Kashiwa, Chiba, Japan

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Publications (22)43.71 Total impact

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    ABSTRACT: Posterior decompression with instrumented fusion (PDF) surgery has been previously reported as a relatively safe surgical procedure for any type of thoracic ossification of the longitudinal ligament (OPLL). However, mid- to long-term outcomes are still unclear. The aim of the present study was to elucidate the mid- to long-term clinical outcome of PDF surgery for thoracic OPLL patients. The present study included 20 patients who had undergone PDF for thoracic OPLL and were followed for at least 5 years. Increment change and recovery rate of the Japanese Orthopaedic Association (JOA) score were assessed. Revision surgery during the follow-up period was also recorded. Average JOA scores were 3.5 preoperatively and 7.1 at final follow-up. The average improvement in JOA score was 3.8 points and the average recovery rate was 47.0%. The JOA score showed gradual increase after surgery, and took 9 months to reach peak recovery. As for neurological complications, two patients suffered postoperative paralysis, but both recovered without intervention. Six revision surgeries in four patients were related to OPLL. Additional anterior thoracic decompression for remaining ossification at the same level of PDF surgery was performed in one patient. Decompression surgery for deterioration of symptoms of pre-existing cervical OPLL was performed in three patients. One patient had undergone lumbar and cervical PDF surgery for de novo ossification foci of the lumbar and cervical spine. PDF surgery for thoracic OPLL is thus considered a relatively safe and stable surgical procedure considering the mid- to long-term outcomes.
    No preview · Article · Jan 2016 · Journal of Clinical Neuroscience
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    ABSTRACT: Symptom of herpes zoster is sometimes difficult to distinguish from sciatica induced by spinal diseases, including lumbar disc herniation and spinal canal stenosis. Here we report a case of sciatica mimicking lumbar canal stenosis. A 74-year-old Chinese male patient visited our hospital for left-sided sciatic pain upon standing or walking for 5 min of approximately 1 month's duration. At the first visit to our hospital, there were no skin lesions. A magnetic resonance imaging showed spinal canal stenosis between the 4th and 5th lumbar spine. Thus, we diagnosed the patient with sciatica induced by spinal canal stenosis. We considered decompression surgery for the stenosis of 4th and 5th lumbar spine because conservative therapy failed to relieve the patient's symptom. At that time, the patient complained of a skin rash involving his left foot for several days. A vesicular rash and erythema were observed on the dorsal and plantar surfaces of the great toe and lateral malleolus. The patient was diagnosed with herpes zoster in the left 5th lumbar spinal nerve area based on clinical findings, including the characteristics of the pain and vesicular rash and erythema in the 5th lumbar spinal dermatome. The patient was treated with famciclovir (1,500 mg/day) and non-steroidal anti-inflammatory drugs. After 1 week of medication, the skin rash resolved and pain relief was obtained. In conclusion, spinal surgeons should keep in mind herpes zoster infection as one of the possible differential diagnoses of sciatica, even if there is no typical skin rash.
    Full-text · Article · Dec 2015 · BMC Research Notes
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    ABSTRACT: Background Cervical deformity can influence global sagittal balance. We report two cases of severe low back pain and lower extremity radicular pain associated with dropped-head syndrome. Symptoms were relieved by cervical corrective surgery. Case presentation Two Japanese women with dropped head syndrome complained of severe low back pain and lower extremity radicular pain on walking. Radiographs showed marked cervical spine kyphosis and lumbar spine hyperlordosis. After cervicothoracic posterior corrective fusion was performed, cervical kyphosis was corrected and lumbar lordosis decreased, and low back pain and leg pain were relieved in both patients. Conclusions Cervical deformity can influence global sagittal balance. Marked cervical kyphosis in patients with dropped-head syndrome can induce compensatory thoracolumbar hyperlordosis. Low back symptoms in patients with dropped-head syndrome are attributable to this compensatory lumbar hyperlordosis. Symptoms of lumbar canal stenosis may result from cervical deformity and can be improved with cervical corrective surgery. Electronic supplementary material The online version of this article (doi:10.1186/s13104-015-1430-3) contains supplementary material, which is available to authorized users.
    Full-text · Article · Dec 2015 · BMC Research Notes
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    ABSTRACT: Spinal cord injury (SCI) can cause neuropathic pain (NeP), often reducing a patient's quality of life. We recently reported that granulocyte colony-stimulating factor (G-CSF) could attenuate NeP in several SCI patients. However, the mechanism of action underlying G-CSF-mediated attenuation of SCI-NeP remains to be elucidated. The purpose of the present study was to elucidate the therapeutic effect and mechanism of action of granulocyte colony-stimulating factor for SCI-induced NeP. T9 level contusive SCI was introduced to adult male Sprague Dawley rats. Three weeks after injury, rats received intraperitoneal recombinant human G-CSF (15.0μg/kg) for 5days. Mechanical allodynia was assessed using von Frey filaments. Immunohistochemistry and western blot analysis were performed in spinal cord lumbar enlargement samples. Testing with von Frey filaments showed significant increase in the paw withdrawal threshold in the G-CSF group compared with the vehicle group 4weeks, 5weeks, 6weeks and 7weeks after injury. Immunohistochemistry for CD11b (clone OX-42) revealed that the number of OX-42-positive activated microglia was significantly smaller in the G-CSF group than that in the vehicle rats. Western blot analysis indicated that phosphorylated-p38 mitogen-activated protein kinase (p38MAPK) and interleukin-1β expression in spinal cord lumbar enlargement were attenuated in the G-CSF-treated rats compared with that in the vehicle-treated rats. The present results demonstrate a therapeutic effect of G-CSF treatment for SCI-induced NeP, possibly through the inhibition of microglial activation and the suppression of p38MAPK phosphorylation and the upregulation of interleukin-1β. Copyright © 2015 Elsevier B.V. All rights reserved.
    No preview · Article · May 2015 · Journal of the Neurological Sciences
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    ABSTRACT: We report on Japanese patients who showed neurological deterioration induced by sitting after cervicothoracic posterior decompression with instrumented fusion, but showed immediate neurological recovery after bed rest. Patients showed incomplete paraparesis caused by the ossification of the posterior longitudinal ligament at uppermost thoracic spine. Cervicothoracic posterior decompression with instrumented fusion was performed. Postoperatively, the patients showed partial paraparesis when they were sitting. They showed rapid recovery from lower extremity paralysis upon lying down. After strict bed rest for one month, those patients showed no apparent development of paralysis during sitting. In patients with postoperative residual anterior spinal cord compression, micromotion might exacerbate neurological symptoms.
    Full-text · Article · Apr 2015 · BMC Research Notes
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    ABSTRACT: The motion at the non-ossified segment of the ossification of the posterior longitudinal ligament (OPLL) is thought to be highly correlated to aggravation of symptoms of myelopathy. The rationale for posterior decompression with instrumented fusion (PDF) surgery is to limit the motion of the non-ossified segment of OPLL by stabilization. The purpose of the present study was to elucidate the course of bone union and remodelling of the non-ossified segment of thoracic OPLL (T-OPLL) after PDF surgery. A total of 29 patients who underwent PDF surgery for T-OPLL were included in this study. We measured the thickness of the OPLLs by determining the thickest part of the OPLL in the sagittal multi-planer reconstruction CT images pre- and post-operatively. Five experienced spine surgeons independently performed CT measurements of OPLL thickness twice. Japanese Orthopaedic Association score for thoracic myelopathy was measured as clinical outcome measure. Non-ossified segment of OPLLs fused in 24 out of 29 (82.8 %) patients. The average thickness of the OPLL at its thickest segment was 8.0 mm and decreased to 7.3 mm at final follow-up. The decrease in ossification thickness was significantly larger in the patients who showed fusion of non-ossified segments of OPLL compared with that in the patients did not show fusion. There was no significant correlation between the clinical outcome and the decrease in thickness of the OPLLs. The results of this study showed that remodelling of the OPLLs, following fusion of non-ossified segment of OPLLs, resulted in a decreased OPLL thickness, with potential for a reduction of spinal cord compression.
    No preview · Article · Mar 2015 · European Spine Journal
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    ABSTRACT: Epidermoid cysts are known as embryonic or acquired ectopic aberrations of the ectoderm. To the best of our knowledge, there are only a few reports of elderly onset intramedullary epidermoid cysts. We report a case of elderly onset intramedullary epidermoid cyst at the conus medullaris. A 63-year-old Japanese woman working as a farmer presented with slowly progressive gait disturbance and voiding dysfunction. A magnetic resonance imaging scan revealed an intramedullary mass lesion at L1 to L3. We diagnosed the lesion as an intramedullary spinal cord tumor. A laminectomy was performed at the level of Th12 to L3. Upon spinal cord dissection, a yellowish milky exudation erupted from the cystic lesion. We resected white cartilage-like pieces from the cystic cavity. Because the wall of the cystic lesion tightly adhered to the spinal cord parenchyma, we abandoned complete resection of the cyst wall. The pathological diagnosis was an epidermoid cyst. We propose that evacuation of the cyst contents is preferable, especially in cases with elderly onset and congenital origin.
    Full-text · Article · Jan 2015 · Journal of Medical Case Reports
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    ABSTRACT: Hemorrhage caused by spinal cord hemangioblastoma is rare, usually presenting as a subarachnoid hemorrhage. Intramedullary hemorrhage is an extremely rare manifestation of spinal cord hemangioblastoma. Forty-year-old Japanese male patient presented with acute paraplegia. Magnetic resonance (MR) imaging of the spinal cord revealed intramedullary hemorrhage. An intramedullary mass lesion was detected at the 8th thoracic vertebral level (T8) in a gadolinium enhanced-MR image. Spinal angiography revealed an intramedullary tumor stain at the level of T8. Therefore we diagnosed the problem as intramedullary hemorrhage caused by the hemangioblastoma. One month after the onset, extirpation of the intramedullary hemangioblastoma was performed. The tumor was completely removed. Pathological findings revealed a typical hemangioblastoma. At his final follow-up visit, the patient showed no apparent neurological recovery. Hemangioblastoma can be a cause of intramedullary hemorrhage should be considered in such cases.
    Full-text · Article · Nov 2014 · BMC Research Notes
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    ABSTRACT: Context We present a rare and interesting case of hemorrhagic lumbar facet cysts accompanying a spinal subdural hematoma at the same level suggesting a possible mechanism by which spinal subdural hematomas can arise. Findings A 71-year-old man presented with persistent sciatic pain and intermittent claudication. Magnetic resonance imaging demonstrated a multilocular mass lesion that showed high signal intensity in both T1- and T2-weighted images, and was located both inside and outside of the spinal canal. Computed tomographic myelography showed a cap-shaped block of the dural tube at L5 and computed tomography with L5-S facet arthrography demonstrated cystic masses. The patient was diagnosed with lumbar radiculopathy caused by hemorrhagic facet cysts, and then progressed to surgical treatment. Surgery revealed that the cysts contained blood clots, and intraoperative findings that the inside of the dural tube appeared blackish and that the dural tube was tensely ballooned after removal of the cysts led us to explorative durotomy. The durotomy demonstrated concentrated old blood pooling both in the dorsal and ventral subdural space, and these spaces were subsequently drained. After surgery, his sciatic pain and intermittent claudication resolved. There was no evidence of cyst mass recurrence at 2 years of follow-up. Conclusion We propose a newly described mechanism for the formation of spinal subdural hematomas. We recommend surgeons be alert to epidural lesions causing repeated acute compression of the dural tube, which can cause spinal subdural hematoma, and consider the possible coexistence of these lesions in diagnosis and strategic surgical decisions.
    No preview · Article · Jun 2014 · The journal of spinal cord medicine

  • No preview · Article · Jan 2014 · Journal of Orthopaedic Science

  • No preview · Article · Dec 2013 · Journal of Orthopaedic Science
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    ABSTRACT: Study Design. An open-labeled multicenter prospective non-randomized controlled clinical trialObjective. To confirm the feasibility of using granulocyte colony-stimulating factor (G-CSF) for treatment of acute spinal cord injury (SCI)Summary of Background Data. We previously reported that G-CSF promotes functional recovery after compression-induced spinal cord injury (SCI) in mice. Based on these findings, we conducted a multicenter prospective controlled clinical trial to assess the feasibility of G-CSF therapy for patients with acute SCI.Methods. The trial ran from August 2009 to March 2011, and included 41 SCI patients treated within 48 hours of onset. Informed consent was obtained from all patients. After providing consent, patients were divided into two groups. In the G-CSF group (17 patients), G-CSF (10 μg/kg/day) was intravenously administered for five consecutive days, and in the control group (24 patients), patients were similarly treated except for the G-CSF administration. We evaluated motor and sensory functions using the American Spinal Cord Injury Association (ASIA) score and ASIA impairment scale (AIS) at one week, three months, six months, and one year after onset.Results. Only two patients did not experience AIS improvement in the G-CSF group. In contrast, fifteen patients in the control group did not experience AIS improvement. In the analysis of increased ASIA motor score, a significant increase in G-CSF group was detected from one week after the administration compared to the control group. After that, some spontaneous increase of motor score was detected in control group, but the significant increase in G-CSF group was maintained until one year follow-up. Conclusion: Despite the limitation that patient selection was not randomized, the present results suggest the possibility that G-CSF administration has beneficial effects on neurological recovery in patients with acute SCI.
    No preview · Article · Dec 2013 · Spine

  • No preview · Article · Nov 2013 · Neurology India
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    ABSTRACT: PURPOSE: Adjacent segment degeneration (ASD) is one of the major complications of lumbar fusion. Several previous retrospective studies reported ASD after PLIF. However, few reports evaluated whether decompression surgery combined with fusion surgery increases the rate of complications in adjacent segments. The purpose of the current study was to investigate the degeneration in decompressed adjacent segments after PLIF. METHODS: A total of 23 patients (12 men, 11 women; average age, 58.6) who underwent PLIF surgery [1 level (n = 9), 2 levels (n = 8), 3 levels (n = 4), 4 levels (n = 2)] were included. Additional adjacent decompression above or below the level of interbody fusion was performed at 25 levels and no adjacent decompression was performed at 15 levels. We retrospectively investigated ASD by X-ray films of all 40 adjacent segments (above and below fusion level) and clinical outcomes of all 23 cases. RESULTS: Of the 40 adjacent segments, 19 (47.5 %) showed ASD and 9 (22.5 %) showed symptomatic ASD. In the 19 segments with ASD, ASD occurred in 16 of 25 (64.0 %) segments at decompressed sites compared with 3 of 15 (20.0 %) non-decompressed sites. The ratio of ASD in adjacent segments was significantly higher at decompressed sites than at non-decompressed sites (p < 0.01). CONCLUSION: ASD occurs frequently in association with additional decompression above or below the level of PLIF. In cases in which the adjacent segments require decompression, a surgical strategy that preserves as much of the posterior complex as possible should be selected.
    No preview · Article · Feb 2013 · European Spine Journal
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    ABSTRACT: An open-labeled multicenter prospective controlled clinical trial. To confirm the feasibility of granulocyte colony-stimulating factor (G-CSF) administration for patients with thoracic myelopathy. Although G-CSF is best known as an important cytokine commonly used to treat neutropenia, it also has nonhematopoietic functions. Previous experimental studies have shown that G-CSF can enhance tissue regeneration of several organs, such as the heart and the brain. We previously reported that G-CSF promotes functional recovery after spinal cord injury in rodents. On the basis of those findings, we started a clinical trial of neuroprotective therapy, using G-CSF for patients with worsening symptoms of thoracic myelopathy. Patients whose Japanese Orthopaedic Association (JOA) score for thoracic myelopathy had decreased 2 points or more during a recent 1-month period were eligible for entry. After giving informed consent, patients were assigned to G-CSF and control groups. The G-CSF group (n = 10) received G-CSF 10 μg/kg per day intravenously for 5 consecutive days. The control group (n = 14) received similar treatments as the G-CSF group except for G-CSF administration. The primary outcome was JOA recovery rate at 1 month after G-CSF administration or initial treatment. There was greater improvement in neurological functioning between baseline and 1-month follow-up in the G-CSF group (JOA recovery rate: 29.1 ± 20.5%) than in the control group (JOA recovery rate: 1.1 ± 4.2%) (P < 0.01). No serious adverse events occurred during or after the G-CSF administration. The results provide evidence that G-CSF administration caused neurological recovery in patients with worsening symptoms of thoracic compression myelopathy.
    Full-text · Article · May 2012 · Spine
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    ABSTRACT: We have started a Phase I and IIa clinical trial to assess the safety and feasibility of neuroprotective therapy using granulocyte colony-stimulating factor (G-CSF) for patients with acute spinal cord injury (SCI). Six patients with acute SCI were received intravenous G-CSF injection (5μg/kg per day) for 5 days. After injection, we had neurological evaluations with American Spinal Cord Injury Association (ASIA) score, and confirmed side effects for medication with physical findings and laboratory data. In all 6 patients, some neurological improvement was obtained after medication. Mean white blood cell (WBC) counts were 25.2 to 38.4 (×103/μl) 1 days after medication; that was higher than previous counts. From 1 day to 5 days after the medication, during the administration, WBC counts kept higher than previous counts, and 1 days after the end of medication, WBC counts returned to the previous rate. No severe adverse effects were seen in all patients after G-CSF injection.
    No preview · Article · Jan 2010
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    ABSTRACT: We have started a phase I and IIa clinical trial that evaluates the safety of neuroprotective therapy using granulocyte-colony stimulating factor (G-CSF) for patients with rapidly aggravating compression myelopathy. The trial was performed in five patients, in whom the Japanese Orthopaedic Association score for cervical myelopathy decreased 2 points or more during a recent one-month period. After obtaining informed consent from the patients, G-CSF (5μg/kg/day) was intravenously administrated for five consecutive days. We evaluated the presence of diverse events that related to the G-CSF therapy. We also evaluated motor and sensory functions of the patients and their damaged spinal cord magnetic resonance imaging findings. In all of the five patients, neurological improvement of both motor and sensory functions was obtained, though the degree of the improvement differed depending on the patient. On the day following the start of G-CSF therapy, white blood cell count increased more than 15,200. It was maintained from 15,200 to 43,200 during the administration, and returned to preadministration levels by the third day after the final administration. No adverse event occurred during or after the administration.
    No preview · Article · Jan 2010
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    ABSTRACT: Radial glial cells are neural stem cells (NSC) that are transiently found in the developing CNS. To study radial glia, we isolated clones following immortalization of E13.5 GFP rat neurospheres with v-myc. Clone RG3.6 exhibits polarized morphology and expresses the radial glial markers nestin and brain lipid binding protein. Both NSC and RG3.6 cells migrated extensively in the adult spinal cord. However, RG3.6 cells differentiated into astroglia slower than NSC, suggesting that immortalization can delay differentiation of radial glia. Following spinal cord contusion, implanted RG3.6 cells migrated widely in the contusion site and into spared white matter where they exhibited a highly polarized morphology. When injected immediately after injury, RG3.6 cells formed cellular bridges surrounding spinal cord lesion sites and extending into spared white matter regions in contrast to GFP fibroblasts that remained in the lesion site. Behavioral analysis indicated higher BBB scores in rats injected with RG3.6 cells than rats injected with fibroblasts or medium as early as 1 week after injury. Spinal cords transplanted with RG3.6 cells or dermal fibroblasts exhibited little accumulation of chondroitin sulfate proteoglycans (CSPG) including NG2 proteoglycans that are known to inhibit axonal growth. Reduced levels of CSPG were accompanied by little accumulation in the injury site of activated macrophages, which are a major source of CSPG. However, increased staining and organization of neurofilaments were found in injured rats transplanted with RG3.6 cells suggesting neuroprotection or regrowth. The combined results indicate that acutely transplanted radial glia can migrate to form bridges across spinal cord lesions in vivo and promote functional recovery following spinal cord injury by protecting against macrophages and secondary damage.
    Full-text · Article · Jul 2005 · Experimental Neurology
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    ABSTRACT: Neurotrophins have been shown to promote axonal regeneration, but the techniques available for delivering neurotrophins have limited effectiveness. The aim of this study was to evaluate the effect of adenovirus vector mediated gene transfer of brain-derived neurotrophic factor (BDNF) on axonal regeneration after spinal cord injury. We prepared adenovirus vectors encoding either beta-galactosidase (AxCALacZ) or BDNF (AxCABDNF). AxCALacZ was used to assess infection levels of the adenovirus BDNF produced by AxCABDNF was detected by Western blotting and its bioactivity was confirmed by bioassay. As a model of spinal cord injury, the rat spinal cord was completely transected at the T8 level. Immediately after transection, the vectors were injected into both stumps of the spinal cord. Axonal regeneration after transection was assessed by retrograde and anterograde tracing. In AxCALacZ-injected rats, adenovirus-infected cells were observed not only at the injected site but also in brainstem nuclei, as shown by LacZ expression. After the injection of the retrograde tracer fluorogold (FG) distal portion to the transection, AxCABDNF-injected rats showed FG-labeled neurons in the red nucleus. The anterograde tracer biotinylated dextran amine (BDA) injected into the red nucleus was also found in regenerating rubrospinal fibers distal to the transection. These tracing experiments demonstrated the regeneration of descending axons. In addition, rats of the AxCABDNF group showed significant locomotor recovery of hindlimb function, which was completely abolished by re-transection. These results indicate that the recovery was caused by regeneration of rubrospinal axons, not by simple enhancement of the central pattern generator.
    No preview · Article · Apr 2004 · Journal of Neurotrauma
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    ABSTRACT: We evaluated the effect of brain-derived neurotrophic factor (BDNF) on cell death after spinal cord injury. A rat spinal cord injury model was produced by static load, and continuous intrathecal BDNF or vehicle infusion was carried out either immediately or 3 days after the injury. Cell death was examined by nuclear staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). After injury, typical apoptotic cells were observed. Double staining with TUNEL and specific cell markers revealed that, soon after the injury, the apoptotic or necrotic cells at the injury site were neurons and microglia. One week after the injury, apoptotic oligodendrocytes, but not apoptotic astrocytes, were observed in the white matter rostral and caudal to the injury site, whereas few apoptotic cells were found in the gray matter. The immediate BDNF treatment significantly reduced the number of TUNEL-positive cells in the adjacent rostral site 1 and 2 weeks after the injury, and in the adjacent caudal site 3 days and 1 week after the injury, even though there was no significant difference between BDNF-treated and control rats at the injury site itself. In addition, similar antiapoptotic effects were observed in these regions 1 week after injury in rats that received BDNF treatment from the third day after injury. These findings suggest that BDNF suppresses delayed apoptosis of oligodendrocytes after spinal cord injury, for which even delayed injections are effective. BDNF administration may therefore be useful for the clinical treatment of spinal cord injury through the suppression of secondary events.
    No preview · Article · Jul 2002 · Journal of Neurotrauma

Publication Stats

313 Citations
43.71 Total Impact Points

Institutions

  • 2013-2015
    • Kashiwa City Hospital
      Kashiwa, Chiba, Japan
  • 2002-2015
    • Chiba University
      • Department of Orthopedic Surgery
      Tiba, Chiba, Japan
  • 2014
    • Chiba Kaihin Municipal Hospital
      Tiba, Chiba, Japan
  • 2005
    • Rutgers, The State University of New Jersey
      • W.M. Keck Center for Collaborative Neuroscience
      Newark, NJ, United States