Yukihiko Fujii

Niigata University, Niahi-niigata, Niigata, Japan

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Publications (170)315.36 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Although the introduction of flow-diverter stents has been recognized as a major revolution in the treatment of cavernous carotid aneurysms (CCAs), therapeutic internal carotid artery occlusion (TICAO) remains a reliable procedure for alleviating symptoms caused by CCAs. However, TICAO has the potential risk of the enlargement of coexisting aneurysms that are frequently detected in CCA patients. The purpose of this study is to assess the occurrence of the enlargement of aneurysms coexisting with CCAs after TICAO. We reviewed medical charts of CCA patients who were managed using unilateral TICAO. Coexisting aneurysms were identified using angiograms obtained before TICAO, and imaging data in long follow-up periods were retrospectively examined to determine the extent of the enlargement after TICAO. Of 12 patients with CCAs, 10 had 12 coexisting aneurysms; 5 of the coexisting aneurysms (41.7%) showed enlargement during a mean follow-up period of 8.1 years, and all enlarged aneurysms were smaller of the bilateral CCAs; the larger CCA had been managed by TICAO. Five of 6 (83.3%) patients with bilateral CCAs showed enlargement of the contralateral aneurysm after TICAO. Two contralateral CCAs showed marked enlargement after TICAO and were subsequently treated with stent-assisted coil embolization. Contralateral, smaller aneurysms frequently enlarge after unilateral TICAO in patients with bilateral CCAs. The findings emphasize the importance of long-term observation after TICAO and appropriate interventions against enlarging contralateral aneurysms. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 06/2015; DOI:10.1016/j.jstrokecerebrovasdis.2015.04.025 · 1.99 Impact Factor
  • Clinical Neurophysiology 06/2015; 126(6):e61. DOI:10.1016/j.clinph.2015.02.049 · 2.98 Impact Factor
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    ABSTRACT: Genetic and epigenetic status, including mutations of isocitrate dehydrogenase (IDH) and TP53 and methylation of O(6) -methylguanine-DNA methyltransferase (MGMT), are associated with the development of various types of glioma and are useful for prognostication. Here, using routinely available histology sections from 312 patients with diffuse gliomas, we performed immunohistochemistry using antibodies specific for IDH1 mutation, MGMT methylation status, and aberrant p53 expression to evaluate the possible prognostic significance of these features. With regard to overall survival (OS), univariate analysis indicated that an IDH1-positive profile in patients with glioblastoma (GBM), anaplastic astrocytoma (AA), anaplastic oligoastrocytoma and oligodendroglioma, or a MGMT-negative profile in patients with GBM and AA were significantly associated with a favorable outcome. Multivariate analysis revealed that both profiles were independent factors influencing prognosis. The OS of patients with IDH1-positive/MGMT-negative profiles was significantly longer than that of patients with negative/negative and negative/positive profiles. A p53 profile was not an independent prognostic factor. However, for GBM/AA patients with IDH1-negative/MGMT-negative profiles, p53 overexpression was significantly associated with an unfavorable outcome. Thus, the immunohistochemical profiles of IDH1 and MGMT are of considerable significance in gliomas, and a combination of IDH1, MGMT and p53 profiles may be useful for prognostication of GBM/AA. © 2015 Japanese Society of Neuropathology.
    Neuropathology 05/2015; DOI:10.1111/neup.12196 · 1.80 Impact Factor
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    ABSTRACT: Pharyngeal motor evoked potential (PhMEP) monitoring with a modified endotracheal tube is useful for predicting postoperative swallowing dysfunction. However, the relationship between intraoperative PhMEP findings and recovery from postoperative swallowing dysfunction has not been clarified. We determined whether PhMEP monitoring predicts not only swallowing dysfunction immediately after surgery but also the postoperative recovery period. We analyzed PhMEPs in 36 patients during treatment for skull base tumors. Recovery from postoperative swallowing dysfunction was evaluated when oral intake was started postsurgery and when drip or tube feeding was ended. The correlation between the final to baseline PhMEP ratio and postoperative recovery times from swallowing dysfunction was examined. The PhMEP ratio significantly correlated with postoperative swallowing function immediately after surgery (p < 0.001). The period for starting oral intake in patients with PhMEP ratio of > 50% (mean ± SD, 3.8 ± 4.3 days) was shorter than those with PhMEP ratio of ≤ 50% (mean ± SD, 14.7 ± 11.8 days; p < 0.01). Patients with PhMEP ratio of > 50% (mean ± SD, 13.7 ± 19.2 days) were removed from drip or tube feeding significantly earlier than those with PhMEP ratio of ≤ 50% (mean ± SD, 38.3 ± 27.3 days; p < 0.05). Both univariate and multivariate analysis showed that only PhMEP ratio was predictive of early recovery from swallowing dysfunction. PhMEP monitoring allowed us to predict not only immediate swallowing dysfunction but also the postsurgery period for the recovery from the dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.
    World Neurosurgery 04/2015; DOI:10.1016/j.wneu.2015.04.023 · 2.42 Impact Factor
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    ABSTRACT: The supplementary motor area (SMA) makes multiple reciprocal connections to many areas of the cerebral cortices, such as the primary motor cortex (PMC), anterior cingulate cortex, and various regions in the parietal somatosensory cortex. In patients with SMA seizures, epileptic discharges from the SMA rapidly propagate to the PMC. We sought to determine whether near-infrared spectroscopy (NIRS) is able to intraoperatively display hemodynamic changes in epileptic network activities between the SMA and the PMC. In a 60-year-old male with SMA seizures, we intraoperatively delivered a 500 Hz, 5-train stimulation to the medial cortical surface and measured the resulting hemodynamic changes in the PMC by calculating the oxyhemoglobin (HbO2) and deoxyhemoglobin (HbR) concentration changes during stimulation. No hemodynamic changes in the lateral cortex were observed during stimulation of the medial surface corresponding to the foot motor areas. In contrast, both HbO2 and HbR increased in the lateral cortex corresponding to the hand motor areas when the seizure onset zone was stimulated. In the premotor cortex and the lateral cortex corresponding to the trunk motor areas, hemodynamic changes showed a pattern of increased HbO2 with decreased HbR. This is the first reported study using intraoperative NIRS to characterize the epileptic network activities between the SMA and PMC. Our intraoperative NIRS procedure may thus be useful in monitoring the activities of cortico-cortical neural pathways such as the language system.
    Surgical Neurology International 01/2015; 6(1):44. DOI:10.4103/2152-7806.153872 · 1.18 Impact Factor
  • No shinkei geka. Neurological surgery 01/2015; 43(1):31-40. DOI:10.11477/mf.1436202942 · 0.13 Impact Factor
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    ABSTRACT: Pituitary tumors frequently compress the optic chiasm, causing visual field deficits. Surgical removal of these tumors could improve visual functions. Thus, predicting the prognosis of visual field function is required, but currently there is no method for predicting postoperative visual field status from preoperative data of tumor and optic chiasm characteristics. In this study, we performed preoperative evaluation of visual field prognosis using numerical parameters in 40 patients with pituitary tumors. Data from 30 patients were used to calculate the regression equation and those from the remaining 10 patients were used to confirm the validity of these equations. We defined quantitative values (area of tumor, Atumor; curvature of chiasm, Cchiasm; and area of chiasm, Achiasm) based on tumor size, tumor shape, and optic chiasm shape as determined using magnetic resonance imaging. We determined pre- and postoperative visual field sizes by ophthalmologic methods, and quantified them as numerical values (TNR). Postoperative recovery of the visual fields (obtained by comparing the post- and preoperative visual fields) was confirmed by increased postoperative TNRs (P < 0.01 for 4 isopters and P = 0.01 for 1 isopter, t-test). We attempted to predict postoperative visual field size using preoperative Atumor, Cchiasm, and Achiasm. Multiple regression analysis was performed, and three significant regression equations for predicting visual field size were obtained (N = 30, P < 0.01, F-test). The measured and predicted visual field sizes showed strong correlation (N = 10, r > 0.70). Thus, the quantitative parameters defined in this study clearly predicted postoperative visual functions in patients with pituitary tumor, and could find clinical applications in preoperative evaluation of visual field prognosis in neurosurgery.
    01/2015; 4:80-85. DOI:10.14326/abe.4.80
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    ABSTRACT: IntroductionPrevious magnetic resonance spectroscopy (MRS) and mass spectroscopy studies have shown accumulation of 2-hydroxyglutarate (2HG) in mutant isocitrate dehydrogenase (IDH) gliomas. IDH mutation is known to be a powerful positive prognostic marker in malignant gliomas. Hence, 2HG accumulation in gliomas was assumed to be a positive prognostic factor in gliomas, but this has not yet been proven. Here, we analyzed 52 patients harboring World Health Organization (WHO) grade II and III gliomas utilizing 3.0-tesla MRS.ResultsMutant IDH gliomas showed significantly higher accumulation of 2HG (median 5.077 vs. 0.000, p =0.0002, Mann¿Whitney test). 2HG was detectable in all mutant IDH gliomas, whereas in 10 out of 27 (37.0%) wild-type IDH gliomas, 2HG was below the detectable range (2HG =0) (p =0.0003, chi-squared test). Screening for IDH mutation by 2HG analysis was highly sensitive (cutoff 2HG =1.489 mM, sensitivity 100.0%, specificity 72.2%). Gliomas with high 2HG accumulation had better overall survival than gliomas with low 2HG accumulation (p =0.0401, Kaplan-Meier analysis).Discussion2HG accumulation detected by 3.0-tesla MRS not only correlates well with IDH status, but also positively correlates with survival in WHO grade II and III gliomas.
    11/2014; 2(1):158. DOI:10.1186/s40478-014-0158-y
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    ABSTRACT: Objectives: The study objectives are (1) to identify factors predicting the excellent visual recovery after transsphenoidal removal of pituitary tumors and (2) to describe the association of excellent visual recovery and early restoration of symmetry of the decompressed optic chiasm. Methods: Thirty-five patients with visual symptoms due to pituitary tumors underwent endoscopic endonasal surgery. All patients received perioperative diagnostic magnetic resonance (MR) imaging and ophthalmological assessments within 2 weeks before surgery, within 2 weeks after surgery, and 3 months or later after surgery. Preoperative best-corrected visual acuity (BCVA ≧ 20/20), degree of visual field deficit (VFD, less than half of VF), thickness of retinal nerve fiber layer (RNFL) measured by optical coherence tomography (OCT), and thickness of ganglion cell complex (GCC) measured by OCT were considered for statistical analysis as predictive factors of VF outcome. Multivariate logistic regression models were used in statistical evaluation of data. Results: In the multivariate analysis, RNFL (odds ratio = 62·137, P < 0·001) and preoperative VFD (odds ratio = 8·244, P < 0·02) proved to be effective as factors predicting sufficient VF recovery. Postoperative restoration of symmetry of the optic chiasm was related to sufficient VF recovery (P < 0·0001, Fisher's exact test) and RNFL (P < 0·0001, Fisher's exact test). Discussion: Early decompression is crucial for sufficient VF recovery, in particular, while RNFL preserves normal or borderline thickness and while VFD keeps within hemianopia. Morphological reversibility is associated with functional reversibility in the optic chiasm compressed by a pituitary tumor. In particular, early morphological recovery suggests functional recovery, which indicates neurocyte reserve in the compressed optic pathway with functional recovery.
    Neurological Research 06/2014; DOI:10.1179/1743132814Y.0000000407 · 1.45 Impact Factor
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    ABSTRACT: OBJECTIVE: To determine whether various clinical factors are related to long-term outcomes of patients with sporadic cerebellar hemangioblastomas. METHODS: Subjects included 36 patients (19 men and 17 women) who underwent resection of sporadic hemangloblastorna in the cerebellum Age at surgery ranged from 17 79 years (mean, 49.7 years). The tumor size, which was defined as the largest diameter of the lesion including the extratumoral cyst, ranged from 10-67 mm (mean, 36.4 mm). Obstructive hydrocephalus secondary to mass effect on the fourth ventricle was present in 21 (58.3%) patients preoperatively. RESULTS: Total tumor removal was achieved in 31 of 36 patients (86%). In 4 (11%) patients with solid tumors, postoperative hematoma occurred in the removal cavity, and hernatoma removal was required immediately after surgery. We followed 30 patients for >12 months after the initial surgery (mean, 72.9 months; range, 12-274 months). Recurrence of hemangioblastoma developed in 4 of 30 patients (13%) at 6 months, 17 months, 6 years, and 22 years after surgery. At the final follovv-up examination, 9 (30%) of 30 patients showed some residual neurologic symptoms (poor group), whereas the remaining 21 patients showed no deficits (good group). Using univariate analysis, both age at surgery and tumor characteristics (cystic or solid) were significantly related to long-term patient outcomes (P < 0.05). However, in a multiple logistic regression analysis, only tumor characteristics were correlated with outcomes (P = 0.017). At the final follow-up examination, patients with solid tumors more frequently showed poor outcomes than patients with cystic tumors. CONCLUSIONS: The solid configuration observed on preoperative images of sporadic cerebellar hemangioblastomas is one of the most important clinical factors related to both immediate and long-term outcomes after surgery.
    World Neurosurgery 06/2014; 82(5). DOI:10.1016/j.wneu.2014.06.018 · 2.42 Impact Factor
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    ABSTRACT: Introduction Supratentorial dermoid cysts arise due to the misplacement of embryonic inclusions in the vicinity of the developing neural tube up to the third week of life, when the neural groove begins to close. This report describes a case of a suprasellar dermoid cyst anchored to the anterior optic chiasm, which was accurately located by endoscopic observation, removed gross-totally without visual disturbance, and confirmed pathologically. Although the cyst wall was gross-totally resected, the patient’s impaired visual field returned to a normal level. The resection procedure under endoscopic vision is demonstrated. Material and Method A 22-year-old man gradually developed bitemporal hemianopsia with retrobulbar pain over two months. Magnetic resonance imaging demonstrated a suprasellar cyst with intracystic fat contents forming a fluid level within the lesion. The suprasellar cyst was gross-totally removed with endoscopic endonasal transsphenoidal procedures. Intraoperative inspection confirmed that this cyst arose from the optic chiasm. Pathological examination showed the lesion as a dermoid cyst. Result After gross-totally resection of the cyst, the patient presented a further, transient impairment of bitemporal hemianopsia; at four month follow-up, his visual disturbance was not evident any longer. Conclusion To the best of our knowledge, ours is the only case of a dermoid cyst anchored to the anterior optic chiasma, which was visually confirmed under endoscopic observation. After surgery, the patient presented a transient impairment of the visual field, which was not evident at four month follow-up. It will contribute to a similar case, in which surgeons hesitate to make an incision in the optic chiasm. A subtotal excision should be considered in cases of dermoid cysts anchored to the anterior optic chiasm, because all the previously reported cases of suprasellar dermoid cysts are young people or those who have a relatively long life expectancy.
    06/2014; 1(2). DOI:10.1016/j.inat.2014.03.001
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    ABSTRACT: Object Sacrococcygeal dimples in the gluteal fold, also known as coccygeal pits, are observed in 2%-4% of newborns. Sacrococcygeal dimples are not generally considered to be associated with a significant risk of intraspinal anomalies and therefore are not thought to require further radiographic evaluation. Accordingly, the precise incidence and nature of intraspinal lesions that may be associated with sacrococcygeal dimples is unclear. This study was conducted to determine the incidence of intraspinal lesions in patients with intergluteal dimples. Methods In this study, the authors used MRI to evaluate 103 children who were seen at the Niigata University Medical and Dental Hospital between 2006 and 2011 because of skin abnormalities in the lumbosacral region. Of these children, 14 were excluded as having a subcutaneous fatty mass, and 5 were excluded because the dimples were above the gluteal fold or did not end at the coccyx. The remaining 84 patients were classified according to whether the bottom of the dimple was visible (shallow) or not (deep). The authors also retrospectively examined other skin abnormalities and coexisting anomalies. Results The mean age at the time of MRI evaluation was 11.7 months. Magnetic resonance imaging led to the identification of fibrolipoma of the terminal filum (FTF) in 14 cases (16.7%); 6 of these patients also had a low conus. Classified by depth, there were 58 cases with shallow and 26 with deep dimples. Fibrolipoma of the terminal filum was found in significantly more patients with deep dimples (9 [34.6%]) than in those with shallow dimples (5 [8.6%]). The frequency of other congenital anomalies was significantly higher in patients with FTF-associated dimples (6 [42.9%] of 14) than in those with dimples that were not associated with FTF (9 [12.9%] of 70). Conclusions Fibrolipoma of the terminal filum was identified by MRI in 16.7% of patients with sacrococcygeal dimples. The risk of FTF increased when the dimples were deeply excavated or were accompanied by congenital anomalies. Magnetic resonance imaging should be performed to identify intraspinal lesions when there are high risk factors for intraspinal abnormalities, or when an ultrasound screening suggests intraspinal abnormalities.
    Journal of Neurosurgery Pediatrics 05/2014; DOI:10.3171/2014.4.PEDS13431 · 1.37 Impact Factor
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    ABSTRACT: The authors report a rare case of a huge hypervascular tentorial cavernous angioma treated with preoperative endovascular embolization, followed by successful gross-total removal. A 15-year-old girl presented with scintillation, diplopia, and papilledema. Computed tomography and MRI studies revealed a huge irregularly shaped tumor located in the right occipital and suboccipital regions. The tumor, which had both intra- and extradural components, showed marked enhancement and invasion of the overlying occipital bone. Angiography revealed marked tumor stain, with blood supply mainly from a large branch of the left posterior meningeal artery. Therefore, this lesion was diagnosed as a tentorium-based extraaxial tumor. For differential diagnosis, meningioma, hemangiopericytoma, and malignant skull tumor were considered. Tumor feeders were endovascularly embolized with particles of polyvinyl alcohol. On the following day, the tumor was safely gross totally removed with minimum blood loss. Histopathological examination confirmed the diagnosis of cavernous angioma. To date, there have been no reports of tentorium-based cavernous angiomas endovascularly embolized preoperatively. A tentorial cavernous angioma is most likely to show massive intraoperative bleeding. Therefore, preoperative embolization appears to be quite useful for safe maximum resection. Hence, the authors assert that the differential diagnosis of tentorium-based tumors should include tentorial cavernous angioma, for which preoperative endovascular embolization should be considered.
    Journal of Neurosurgery Pediatrics 05/2014; DOI:10.3171/2014.4.PEDS13628 · 1.37 Impact Factor
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    ABSTRACT: Acute deprivation of unilateral sensory input rapidly enhances contralateral hand motor function, but the underlying mechanisms remain poorly understood. We herein used functional MRI to evaluate, in 14 healthy individuals, motor cortical activation for right finger motion before, during, and after sensory deprivation of left forearm induced by reversible, noninvasive ischemic nerve block (INB). Before INB, the motor task activated the left primary sensorimotor cortex (SM1) as expected. During INB, the volume of the left SM1 activation significantly increased, and, after INB, it returned to the pre-INB, baseline level. The effectiveness of the INB of the left forearm was ensured by confirming disappearance of the activation in right primary sensory cortex that is normally caused by tactile stimulation of the left index finger. These findings demonstrate that acute deafferentation of unilateral forearm causes rapid and reversible changes in the neural substrates for contralateral finger motion, mediated possibly by attenuation of transcallosal interhemispheric inhibition.
    Neuroreport 03/2014; DOI:10.1097/WNR.0000000000000138 · 1.64 Impact Factor
  • Open Journal of Modern Neurosurgery 01/2014; 04(03):126-130. DOI:10.4236/ojmn.2014.43022
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    ABSTRACT: Age is one of the most important prognostic factors in glioblastoma patients, but no standard treatment has been established for elderly patients with this condition. We therefore conducted a retrospective cohort study to evaluate treatment regimens and outcomes in elderly glioblastoma patients. The study population consisted of 79 glioblastoma patients aged ≥76 years (median age 78.0 years; 34 men and 45 women). The median preoperative Karnofsky performance status (KPS) score was 60. Surgical procedures were classified as biopsy (31 patients, 39.2 %), <95 % resection of the tumor (21 patients, 26.9 %), and ≥95 % resection of the tumor (26 patients, 33.3 %). Sixty-seven patients (81.0 %) received radiotherapy and 45 patients (57.0 %) received chemotherapy. The median overall progression-free survival time was 6.8 months, and the median overall survival time was 9.8 months. Patients aged ≥78 years were significantly less likely to receive radiotherapy (p = 0.004). Patients with a postoperative KPS score of ≥60 were significantly more likely to receive maintenance chemotherapy (p = 0.008). Multivariate analyses identified two independent prognostic factors: postoperative KPS score ≥60 (hazard ratio [HR] = 0.531, 95 % confidence interval [CI] 0.315-0.894, p = 0.017) and temozolomide therapy (HR = 0.442, 95 % CI 0.25-0.784, p < 0.001).The findings of this study suggest that postoperative KPS score is an important prognostic factor for glioblastoma patients aged ≥76 years, and that these patients may benefit from temozolomide therapy.
    Journal of Neuro-Oncology 10/2013; DOI:10.1007/s11060-013-1291-3 · 2.79 Impact Factor
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    ABSTRACT: The efficacy and toxicity of high-dose methotrexate (HD-MTX)-based chemotherapy were retrospectively reviewed in patients with primary central nervous system lymphoma (PCNSL). All immunocompetent patients with histologically or radiographically diagnosed PCNSL treated between 2006 and 2012 at Niigata University Hospital were enrolled. Thirty-eight patients with a diagnosis of PCNSL were treated with one of two regimens during different time periods. During the first period, from 2006 to 2009, three 3-week cycles of MPV (MTX + procarbazine + vincristine) were administered (MPV3 group). In the second period, from 2010 to 2012, five 2-week cycles of MTX were administered (MTX5 group). High-dose cytarabine was used in both groups following HD-MTX-based chemotherapy. Whole-brain radiotherapy was used for patients who did not attain a complete response (CR) based on magnetic resonance images. In the MPV3 group, 20 out of 23 patients (87%) completed the planned treatment. The CR rate after chemotherapy was 30%, and 57% after radiation therapy. Thirteen out of 15 patients (87%) in the MTX5 group completed the planned treatment. The CR rates after chemotherapy and radiation therapy were 53% and 93%, respectively. Renal dysfunction was assessed by measuring creatinine clearance rates, which were very similar in both groups. In terms of hematologic toxicity and other adverse reactions, there was no significant difference between the two groups. In conclusion, dose-dense MTX chemotherapy improved outcome with acceptable toxicity compared with the treatment schedule for three cycles of MPV treatment.
    Neurologia medico-chirurgica 10/2013; 53(11). DOI:10.2176/nmc.oa2013-0195 · 0.65 Impact Factor
  • Neuropathology 09/2013; DOI:10.1111/neup.12072 · 1.80 Impact Factor
  • Clinical Neurophysiology 08/2013; 124(8):e32-e33. DOI:10.1016/j.clinph.2013.02.087 · 2.98 Impact Factor
  • Clinical Neurophysiology 08/2013; 124(8):e32. DOI:10.1016/j.clinph.2013.02.086 · 2.98 Impact Factor

Publication Stats

2k Citations
315.36 Total Impact Points

Institutions

  • 1994–2015
    • Niigata University
      • • Division of Neurosurgery
      • • Brain Research Institute
      • • Division of Integrated Neuroscience
      Niahi-niigata, Niigata, Japan
  • 2013
    • Stem Cell And Brain Research Institute
      Lyons, Rhône-Alpes, France
  • 2009–2010
    • Niigata City General Hospital
      Niahi-niigata, Niigata, Japan
    • Nagaoka Red Cross Hospital
      Нагаока, Niigata, Japan
  • 1998–2008
    • University of California, Davis
      • Department of Neurology
      Davis, California, United States