Publications by authors named "Toshiyuki Okazaki"

Lumbar subcutaneous edema (LSE) is sometimes found within the deep subcutaneous or perifascial tissue on magnetic resonance imaging (MRI) via short-tau inversion recovery or fat-suppressed T2-weighted imaging. It is more likely to occur in older patients and those with obesity. However, no studies have focused on the association between LSE and local alignment.

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Study Design: This was a retrospective, observational study.

Objectives: Postoperative axial pain (AP) is a well-known complication of cervical posterior surgery. It can be caused by various reasons, but the etiology remains unclear.

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Cylindrical cages were known to cause subsidence after anterior cervical discectomy and fusion (ACDF); hence, they were gradually replaced by box-shaped cages. However, this phenomenon has been inconclusive due to limited information and short-term results. Therefore, this study aimed to clarify risk factors for subsidence after ACDF using titanium double cylindrical cages with mid-term follow-up periods.

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The classification of spinal extradural arteriovenous fistulas (AVFs) was reported based on a case series treated by microsurgery in 2009 and endovascular interventions in 2011. The present report describes a patient with extradural AVFs at the cervical spine manifesting gradual progressive radiculomyelopathy of bilateral upper extremities. Magnetic resonance imaging (MRI) revealed a mass sign from C1 to C4 at the right ventral side and the spinal cord was deviated to the left and indicated as a flow void sign.

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Objective: Although intravenous indocyanine green (ICG) videoangiography has been reported to be useful when applied to cerebral arteriovenous malformation (AVM) surgery, the ICG that remains after the procedure makes it difficult to understand the anatomy, to evaluate nidus blood flow changes, and to repeat ICG videoangiography within a short time. Intraarterial ICG videoangiography has emerged as a way to overcome these limitations. The current study presents the results of intraarterial ICG videoangiography undertaken in patients with cerebral AVMs.

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Background: Bow hunter's syndrome (BHS) is caused by posterior circulation insufficiency that results from the occlusion or compression of the vertebral artery (VA) during neck rotation. Owing to its rarity, there is no guideline to support the decision of selecting a conservative or a surgical approach. Management of BHS is dependent on each patient.

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Carotid endarterectomy (CEA) is widely used for cervical artery stenosis. In Japan, primary closure after endarterectomy has been a standard technique. Recently, the patch closure has been shown to be superior to the primary suture for the prevention of restenosis and ipsilateral stroke.

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Among the III-nitride semiconductors, InGaN is a key material for visible optical devices such as light-emitting diodes (LEDs), laser diodes, and solar cells. Light emission is achieved via electron-hole recombination within the InGaN layer. When InGaN-based blue LEDs were first commercialized, the high probability of electron-hole radiative recombination despite the presence of numerous threading dislocations was a mystery.

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The observation of walking improves gait ability in chronic stroke survivors. It has also been suggested that activation of the mirror neuron system contributes to this effect. However, activation of the mirror neuron system during gait observation has not yet been assessed in sub-acute stroke patients.

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This study was to assess the efficacy of microdiscectomy, cage fixation, and right tranuncal foramintomy for the patients suffering from right radiulo-myelopathy. Anterior cervical foraminotomy was reported to be an effective option for the treatment of cervical degenerative radiculopathy but with the problem of recurrence. Since Hakuba reported the method of trans-unco-discal approach in 1976, it was designed as keyhole foraminotomy which was called transuncal approach, transpedicular approach or transvertebral approach.

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Surgery for- and endovascular treatment of vertebral artery (VA) dissecting aneurysms involving the origin of the posterior inferior cerebellar artery (PICA) remain challenging. Their ideal treatment is complete isolation of the aneurysm by surgical or endovascular trapping plus PICA reconstruction. However, postoperative lower cranial nerve palsy and medullary infarction are potential complications.

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Background: Glioblastoma multiforme (GBM) is the most malignant of brain tumors. Acquired drug resistance is a major obstacle for successful treatment. Earlier studies reported that expression of the multiple drug resistance gene (MDR1) is regulated by YB-1 or NFκB via the JNK/c-Jun or Akt pathway.

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Background: Spontaneous intracranial hypotension (SIH) has been increasingly recognized as a phenomenon caused by cerebrospinal fluid (CSF) leaks; however, its pathogenesis remains unclear.

Case Description: We report 2 cases of SIH resulting from CSF leak from a meningeal diverticulum at the C2 nerve root sleeve. The first case is that of a 46-year-old man who experienced orthostatic headache after a bicycle accident at age 45.

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Spontaneous and chronic epidural hematoma (SSEH) in the lumbar spine is rare, and idiopathic and chronic SSEH in the lumbar spine is extremely rare disease. Most of lumbar SSEH were acute and secondary with trauma, hematologic disorders, drug, and surgical procedure. Only 20 cases of chronic SSEH in the lumbar spine have been reported and 14 cases among them were considered to be idiopathic.

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Objective: Superficial temporal artery (STA)-to-middle cerebral artery (MCA) bypass is an established surgical technique for achieving revascularization. It is important to select the proper recipient artery of the MCA. Three-dimensional computed tomographic angiography (3D-CTA) and conventional angiography are useful in the selection process but need contrast agents.

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OBJECTIVE Anterior cervical discectomy and fusion (ACDF) procedures are performed to treat patients with cervical myelopathy or radiculopathy. Dysphagia is a post-ACDF complication. When it coincides with prevertebral space enlargement and inflammation, surgical site infection and pharyngoesophageal perforation must be considered.

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Objectives: This study was to investigate the efficacy of bone scintigraphy in order to diagnose the correct level of vertebral compression fractures (VCF) for the severe back pain before balloon kyphoplasty (BKP) was performed.

Patients And Methods: A total of 30 consecutive patients were treated with BKP for 38 times since May 2012. Eleven patients had acute multi-level VCFs.

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Acute internal carotid artery (ICA) occlusion may result in severe disability or death. Revascularization by carotid artery stenting after treatment with intravenous (iv) recombinant tissue-type plasminogen activator (rt-PA) has been documented. However, there are few reports on emergency carotid endarterectomy (CEA) within 24 hours after the iv administration of rt-PA.

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The effect of the third member of the Dickkopf family (DKK3) in the Wnt pathway in glioblastoma remains unclear. We first demonstrated the non-specific interaction of Wnt3a and Wnt5a with the receptors LRP6 and ROR2 and the up-regulation of the Wnt pathway in glioblastoma cells. We used an adenovirus vector and found that an increase in DKK3 protein attenuated the expression of Wnt3a, Wnt5a and LRP6, but not of ROR2, and their interaction, thereby affecting both canonical- and non-canonical Wnt downstream cascades.

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Background: Previous studies reported that the plasma d-dimer level reflects the activity of thrombus formation in the left atrium of patients with acute cerebral infarction and acute aortic dissection (AAD). Brain natriuretic peptide (BNP) is considered to be a marker of chronic heart failure. The differential diagnosis in the emergency room between stroke due to cardioembolism and AAD is difficult but important for early treatment especially in patients requiring intravenous thrombolysis with a recombinant tissue-type plasminogen activator.

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Boron neutron capture therapy (BNCT) has been reported to be effective in the patients with glioblastoma multiforme (GBM). Median survival time (MST) of GBM patients treated with BNCT is approximately two years. GBM patients surviving 2 or 3 years are considered long-term survivors.

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Interferon-beta (IFN-β) is reported to augment anti-tumor effects by temozolomide in glioblastoma via down-regulation of MGMT. Promyelocytic leukemia (PML), a gene induced by IFN-β, is a tumor suppressor. Here, we report for the first time that in combination therapy, an IFN-β-induced increase in endogenous PML contributes to anti-tumor effects in p53 wild- and mutant glioma cells in a xenograft mice model.

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A 40-year-old male smoker presented with a ruptured saccular aneurysm that formed de novo 10 months after normal magnetic resonance (MR) angiography findings. Computed tomography of the head at the second admission showed subarachnoid hemorrhage in the interhemispheric fissure and anterior basal cistern. MR and conventional cerebral angiography revealed an aneurysm arising from the anterior communicating artery (AcomA).

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We report a 5 year-old boy with primary anaplastic pleomorphic xanthoastrocytoma (PXA) with whole neuroaxis dissemination at diagnosis who experienced the sudden onset of generalized convulsion. Head- and spinal magnetic resonance imaging (MRI) showed widespread gadolinium (Gd)-enhanced lesions extending to the bilateral frontal- and medial temporal lobes and the spinal cord. Subsequent MRI study demonstrated that the lesion size increased without any neurological deterioration.

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