Details of a Researcher - Akiyama, Takenori

Papers - Akiyama, Takenori

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Optic nerve seeding of atypical meningiomas presenting with subacute visual loss: 2 case reports with genetic characterization

Kitamura, Yohei, Akiyama, Takenori, Sasaki, Hikaru, Hayashi, Yuichiro, Yoshida, Kazunari

JOURNAL OF NEUROSURGERY (AMER ASSOC NEUROLOGICAL SURGEONS) 119 ( 2 ) 494 - 498 2013.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 0022-3085

Meningiomas rarely cause CSF dissemination, and CSF seeding to the optic nerve (ON) is extremely rare. This is the first report of 2 cases of atypical meningioma with subacute visual loss due to ON seeding. The authors present the genetic characteristics of these atypical meningiomas with CSF dissemination. The patient in Case 1 was a 36-year-old woman with a 1.5-cm mass within the left ON, and the patient in Case 2 was a 70-year-old woman with a 0.9-cm mass around the right ON. Both individuals had undergone multiple surgeries for primary lesions and local recurrent lesions. They presented with subacute visual loss, and both tumors were completely resected. The pathological diagnosis was atypical meningioma with high MIB-1 indices and p53-positive cell ratios in each case. Comparative genomic hybridization showed significant chromosomal copy number alterations similar to the results of previous surgeries, confirming that the tumors were disseminated lesions. The present findings suggest that genetic characteristics, such as 1p and 10qcen-23 losses and 17q and 20 gains, shared by the 2 cases might be associated with CSF dissemination of meningiomas.

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Whole-brain CT digital subtraction angiography of cerebral dural arteriovenous fistula using 320-detector row CT

Fujiwara, Hirokazu, Momoshima, Suketaka, Akiyama, Takenori, Kuribayashi, Sachio

NEURORADIOLOGY (SPRINGER) 55 ( 7 ) 837 - 843 2013.07

Research paper (scientific journal), Joint Work, ISSN 0028-3940

The purpose of this study was to evaluate the usefulness of CT digital subtraction angiography (CTDSA) by using 320-detector row CT in the diagnosis and classification of cerebral dural arteriovenous fistula (dAVF) and comparing it with DSA as the standard reference.
A total of 29 CTDSA/DSA from 25 patients with dAVF were retrospectively evaluated by two neuroradiologists. The presence, Cognard classification, and feeding arteries of dAVFs on CTDSA were assessed according to DSA.
DSA depicted 33 dAVFs in 28 cases. By consensus reading, CTDSA correctly detected 32 dAVFs in 27 cases and properly graded 31 lesions. The intermodality agreement for the presence and classification of dAVFs was excellent (kappa = 0.955 and 0.921, respectively). CTDSA detected 77 of 109 feeding arteries (70.6 %) in 25 cases. The intermodality agreement for the feeding arteries was good (kappa = 0.713).
Although CTDSA is limited in temporal and spatial resolution in comparison with DSA, it is an effective non-invasive tool for the detection and classification of dAVF.

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Glue embolization by direct puncture technique for maxillary AVM presenting with oral hemorrhage

AKIYAMA Takenori, SHIBAO Shunsuke, TOMIO Ryosuke, ONOZUKA Satoshi, ASODA Seiji, YOSHIDA Kazunari

Journal of Neuroendovascular Therapy (The Japanese Society for Neuroendovascular Therapy) 7 ( 1 ) 32 - 39 2013

ISSN 1882-4072

Objective: We report a case of maxillary arterio-venous malformation (AVM) with recurrent palatal hemorrhages successfully treated with direct puncture and injection of n-butyl-2-cyanoacrylate (NBCA).Case presentation: A 47-year-old female had been followed up for multiple craniofacial AVMs. Endovascular treatment was planned because of exacerbation of recurrent bleeding from dilated abnormal vessels on the palate surface. Pre-treatment angiography revealed an intramaxillary AVM, part of which bulged into oral cavity suggesting a bleeding point. Direct puncture embolization was selected inasmuch as effective transarterial embolization might be made difficult by the presence of narrow and tortuous feeders. Diluted NBCA was directly injected into the lesion and complete hemostasis was achieved without any complications.Conclusion: NBCA injection directly into a bleeding point of an AVM on the palate surface can be performed safely and effectively and therefore should be considered a primary treatment option.

Recanalisation of spontaneously occluded vertebral artery dissection after subarachnoid haemorrhage

Akiyama, Takenori, Onozuka, Satoshi, Horiguchi, Takashi, Yoshida, Kazunari

NEUROSURGICAL REVIEW (SPRINGER) 35 ( 4 ) 615 - 619 2012.10

Research paper (scientific journal), ISSN 0344-5607

Spontaneous occlusion is a rare manifestation of ruptured vertebral artery dissection (VAD). Its natural history and treatment strategy have yet to be established due to its rarity. Here, we report five lesions involving spontaneous occlusion of VAD after subarachnoid haemorrhage, among which three lesions showed recanalisation. Based on our experience and previous reports, spontaneous occlusion of ruptured VAD can be classified into two groups-one group with occlusion in the acute stage with a high incidence of recanalisation and another group with occlusion in the chronic stage with a relatively low incidence of recanalisation. The underlying mechanism is likely different in each group, and treatment strategies should also be tailored depending on the pathophysiology.

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Optic nerve sheath solitary fibrous tumor

Kitamura, Yohei, Akiyama, Takenori, Hirose, Shigemichi, Yoshida, Kazunari

ACTA NEUROCHIRURGICA (SPRINGER WIEN) 154 ( 4 ) 633 - 635 2012.04

Research paper (scientific journal), Joint Work, ISSN 0001-6268

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Hemorrhagic onset of cerebellar pilocytic astrocytoma in an adult: a case report and review of the literature implying a possible relation of degenerative vascular changes to the massive intratumoral hemorrhage

Shibao, Shunsuke, Kimura, Tokuhiro, Sasaki, Hikaru, Fujiwara, Hirokazu, Akiyama, Takenori, Ueno, Mari, Shidoh, Satoka, Yoshida, Kazunari

BRAIN TUMOR PATHOLOGY (SPRINGER TOKYO) 29 ( 2 ) 96 - 102 2012.04

Research paper (scientific journal), Joint Work, ISSN 1433-7398

Pilocytic astrocytoma (PA) is a low-grade astrocytic tumor arising predominantly during the first two decades of life. Hemorrhagic onset of PAs is uncommon, and the etiology of hemorrhage remains unclear. Here we report a case of hemorrhagic onset of cerebellar PA in a 29-year-old man who presented with a week-long history of headache and gait instability. Computed tomography and magnetic resonance imaging revealed a hemorrhagic tumor located in the right cerebellar hemisphere, and total resection was performed. Histological examination showed bipolar glial cell proliferation in a biphasic pattern in a compact area and a loose microcystic area with Rosenthal fibers and eosinophilic granular bodies, indicating PA. Prominent changes in tumor vasculature, including aggregation of sclerotic thick-walled and ectatic thin-walled vessels, was observed, and nodules of thrombi containing complex vascular proliferation suggesting recanalized thrombi formed in partially ruptured vessels were also found. Thus, rupture of these abnormal vessels appeared to be the cause of hemorrhage. Review of the literature revealed that age distribution of patients with hemorrhagic PAs tends to be older than that of patients with general PAs. These findings imply a possibility that degenerative changes in blood vessels in long-standing PAs might be related to the mechanisms of spontaneous intratumoral hemorrhage.

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Severe Parkinsonism Following Endoscopic Third Ventriculostomy for Non-communicating Hydrocephalus -Case Report-

Akiyama, Takenori, Tanizaki, Yoshio, Akaji, Kazunori, Hiraga, Kenji, Akiyama, Takekazu, Takao, Masaki, Ohira, Takayuki

NEUROLOGIA MEDICO-CHIRURGICA (JAPAN NEUROSURGICAL SOC) 51 ( 1 ) 60 - 63 2011.01

Research paper (scientific journal), ISSN 0470-8105

A 23-year-old male with non-communicating hydrocephalus caused by intraventricular hemorrhage from an arteriovenous malformation was treated by endoscopic third ventriculostomy (ETV) after repeated ventricular cerebrospinal fluid drainage and removal of ventriculoperitoneal shunt due to infection. Postoperatively, the patient developed robust rigidity and akinesia with mutism, suggesting secondary parkinsonism. These symptoms showed marked improvement after administration of levodopa, and were not aggravated after discontinuation. The pathophysiology of this case might involve dysfunction of the dopaminergic system caused by repeated compression and release of the paraventricular white matter. Careful perioperative management not leading to excessive dilation of the the ventricles should be considered for ETV for non-communicating hydrocephalus to avoid this unexpected complication.

Early Embolizations for the Poorest Grade Patients with Ruptured Dissecting Aneurysms of the Vertebral Artery

AKAJI Kazunori, AKIYAMA Takenori, HIRAGA Kenji, TANIZAKI Yoshio, KOJIMA Atsuhiro, OKUI Syunichi

Nosotchu no Geka Kenkyukai koenshu (The Japanese Society on Surgery for Cerebral Stroke) 38 ( 1 ) 24 - 28 2010

ISSN 0914-5508

We report 5 patients (2 females and 3 males) with endovascular coil embolizations for ruptured dissecting aneurysms of the vertebral artery (VA). The age of the patients varies between 44 and 66 (mean 54.8) years. All patients had a Hunt and Kosnik Grade of V at admission. One patient had a dissecting aneurysm of the VA distal to the PICA. One patient had a dissecting aneurysm of the VA without the PICA. Three patients had a dissecting aneurysm of the VA involving the PICA. One patient with a dissecting aneurysm of the VA involving the PICA underwent proximal occlusion, and the other 4 patients underwent internal trapping. All patients underwent endovascular coil embolizations on the day or the next day of the onset. Subsequent rupture occurred in 4 patients before embolization. The Glasgow Outcome Scale at 3 months after the embolization was good recovery in 3 patients. We had no ruptured aneurysm and no coil compaction at 0 to 40 months (mean 26.2 months) after embolization. Our experience showed that the internal trapping for ruptured dissecting aneurysms of the vertebral artery should be performed as soon as possible, even if the patients have a Hunt and Kosnik Grade of V.<br>

De novo development of moyamoya disease in an adult female

Fukaya, Raita, Yoshida, Kazunari, Akiyama, Takenori, Kawase, Takeshi

JOURNAL OF NEUROSURGERY (AMER ASSOC NEUROLOGICAL SURGEONS) 111 ( 5 ) 943 - 946 2009.11

Research paper (scientific journal), Joint Work, ISSN 0022-3085

The origin of moyamoya disease remains unknown. The onset of the angiographically apparent changes of typical moyamoya disease occurs in childhood, but de novo development of the disease has not been confirmed angiographically. The authors report on a case of de novo development of moyamoya disease in a middle-aged female whose cerebral angiography demonstrated no abnormal findings 5 years previously. To the best of the authors' knowledge, this case is the first reported instance of de novo development of definite moyamoya disease verified angiographically. This case demonstrates that the de novo development of moyamoya disease in a middle-aged adult did in fact occur, and angiographically visible features of the disease took < 5 years to complete. (DOI: 10.3171/2009.2.JNS081244)

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頸動脈stent留置術における狭窄部通過困難例に対する工夫 0.035 inch guidewireを用いて

植田良, 赤路和則, 秋山武紀, 谷崎義生, 傳法倫久, 篠田純, 小嶋篤浩, 片山正輝, 菅貞郎, 中村芳樹

JNET: Journal of Neuroendovascular Therapy ((NPO)日本脳神経血管内治療学会) 3 ( 4 ) 310 - 310 2009.11

ISSN 1882-4072

The Possibility of Left Dominant Activation of the Sensorimotor Cortex During Lip Protrusion in Men

Fukunaga, Atsushi, Ohira, Takayuki, Kamba, Masayuki, Ogawa, Seiji, Akiyama, Takenori, Kawase, Takeshi

BRAIN TOPOGRAPHY (SPRINGER) 22 ( 2 ) 109 - 118 2009.09

Research paper (scientific journal), Joint Work, ISSN 0896-0267

Lip protrusion requires bilateral symmetrical movements of the facial muscles, but the laterality of the activated sensorimotor cortex corresponding to the area of the face activated during lip protrusion remains under discussion. In this study, blood-oxygenation-level-dependent (BOLD) responses in the sensorimotor cortex during non-verbal lip protrusion were evaluated in a 3T magnetic field in twenty healthy right-handed subjects. The results showed that the activated sensorimotor area on the left side was larger than that on the right side, and there was a statistically significant difference in the number of activated voxels between the left and right sensorimotor cortex in an individual study of the male group, although approximately symmetrical motor action potentials of facial muscles were recorded during lip protrusion. There was a statistically significant difference in interaction between the hemisphere (right and left) and sex (men and women) and multiple comparison test showed statistical significant differences between "men and right" and "men and left", and between "men and left" and "women and left". The peak value of the percent changes in BOLD signal responses on the left side was approximately twice as high as that on the right side in the males of the group, though the bilateral sensorimotor cortex was almost equally activated in the females in the group. In addition, the left primary sensory area related to the face area was significantly activated as a region where Male was more active than Female in a general linear model (multi-study, multisubject) analysis. This study revealed the possibility that the left sensorimotor cortex was more closely involved in non-verbal mouth movement in men, suggesting sex-related differences in sensorimotor cortex activation.

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頸動脈stent留置術における末梢塞栓保護用deviceの選択 Balloon protectionとReversal flow systemとの併用法の有用性

赤路和則, 秋山武紀, 平賀健司, 谷崎義生, 傳法倫久, 篠田純, 小嶋篤浩, 片山正輝, 菅貞郎, 中村芳樹

JNET: Journal of Neuroendovascular Therapy ((NPO)日本脳神経血管内治療学会) 2 ( 4 ) 161 - 161 2008.11

ISSN 1882-4072

Source analysis of the magnetic field evoked during self-paced finger movements

Niimi, Maki, Ohira, Takayuki, Akiyama, Takenori, Hiraga, Kenji, Kaneko, Yousei, Ochiai, Masato, Fukunaga, Atsushi, Kobayashi, Masahito, Kawase, Takeshi

NEUROLOGICAL RESEARCH (MANEY PUBLISHING) 30 ( 3 ) 239 - 243 2008.04

Research paper (scientific journal), Joint Work, ISSN 0161-6412

Objective: The aim of this study is to investigate a source of cortical magnetic fields evoked by index finger movements.
Methods: We analysed both movement-related cortical fields (MRCFs) and somatosensory-evoked fields (SEFs) by single equivalent current dipole (ECD) method in six healthy subjects. Dipole locations were superimposed on MR images of each individual subject.
Results: The first component after finger movement (movement-evoked field I, MEFI) was observed in all subjects. The dipole of MEFI was oriented posteriorly, and was located on the posterior wall of the central sulcus of the hemisphere contralateral to the movement. The SEFs showed three major components: N20m, P30m and P60m. The dipoles of P30m and P60m were orientated posteriorly, similarly to the MEFI dipole, while that of N20m was orientated anteriorly. The dipole location of MEFI was closely located to P60m, not to N20m and P30m. The mean location of the MEFI dipole was significantly (p < 0.05) superior to N20m.
Conclusion: These findings suggest that MEFI would be generated in the sensory area ( area 3b) affected by multiple afferents and activities, and that the source of the MEFI is not identical to that of the N20m component.

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Hemodynamic response following neuronal activity in cases with severe stenosis of the cervical internal carotid artery and its serial change through carotid artery stenting

AKIYAMA Takenori, OHIRA Takayuki, HIRAGA Kenji, TANIZAKI Yoshio, AKAJI Kazunori, KAWASE Takeshi

Journal of Neuroendovascular Therapy (The Japanese Society for Neuroendovascular Therapy) 2 ( 2 ) 93 - 100 2008

ISSN 1882-4072

Objective: Regional cerebral blood flow (CBF) increasing focally at sites of neural activity is called "hemodynamic response (HDR)". In cases with severe cerebral ischemia, HDR may be disturbed and cause disruption of normal neuro-vascular coupling. HDR was measured during a motor task using functional near infrared spectroscopy (fNIRS) in cases with severe cervical internal carotid artery (ICA) stenosis before and after carotid artery stenting (CAS). Ischemia and the influence of therapy for it on HDR was analyzed.Methods: Seventeen right-handed patients with severe cervical ICA stenosis admitted for CAS were examined. fNIRS during a motor task was performed and concentration changes in oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (HbR), and total hemoglobin (tHb) were calculated in these patients in addition to routine evaluations. The same measurements were repeated after CAS and serial data were evaluated. In order to analyze the relevance of HDR to CBF status, Xenon-enhanced computed tomography (Xe-CT) was performed before and after CAS.Results: Some abnormalities in the HDR curve and its recovery after CAS were detected, including a delay in peak time of tHb concentration, of more than 10 seconds during the 20 second stimulation, in 9 cases. TTP0.7 (time to peak) value, defined as the time to reach seventy percent of maximum tHb concentration, was observed to be higher in patients with low CBF at rest before CAS. In the group with a high TTP0.7 value, CBF at rest before CAS was lower than 35mL/100g/min., significantly lower than the group without a high TTP0.7 value (P<0.01). Additionally, in the group with a high TTP0.7 value, CBF increase after CAS was significantly higher than the group with a lower TTP0.7 value (P<0.01).Conclusions: In some cases with severe ICA stenosis, cortical hemodynamics, and oxygen metabolism during functional activation are disturbed, and CAS can modulate these changes. This result is important in that intervention for cervical IC stenosis can not only reduce ischemic events, but also influence cortical hemodynamics during functional activity.

近赤外線トポグラフィーによる大脳皮質顔面一次運動野描出の試みと問題点

'AKIYAMA TAKENORI, Ohira Takayuki, Hiraga Kenji, Niimi Maki, Fukunaga Atsushi, Kawase Takeshi, Kato Toshinori'

Facial nerve research (日本顔面神経研究会) 23 51-53 2003.12

Research paper (scientific journal), Single Work

Spontaneous resolution of nontraumatic bilateral intracranial vertebral artery dissections―case report―

Fukunaga Atsushi, Tabuse Masanao, Naritaka Heiji, Nakamura Tsuneo, Akiyama Takenori

Neurol Med Chir (Tokyo) (JAPAN NEUROSURGICAL SOC) 42 ( 11 ) 491-495 - 495 2002.11

Research paper (scientific journal), Joint Work, ISSN 0470-8105

A 49-year-old man presented with nontraumatic bilateral intracranial vertebral artery dissections without subarachnoid hemorrhage manifesting as Wallenberg's syndrome on the right. Magnetic resonance imaging revealed an infarct in the right dorsolateral aspect of the medulla oblongata. Antiplatelet therapy was administered. Vertebral angiography performed on the 9th hospital day (Day 9) revealed pearl and string sign in the right vertebral artery and narrowing of the left vertebral artery. Second angiography performed on Day 25 showed no change, but third angiography performed on Day 74 revealed spontaneous resolution of the bilateral vertebral artery dissections. Magnetic resonance angiography performed on Day 250 showed no evidence of dissection. However, magnetic resonance imaging revealed a small infarct in the splenium of the corpus callosum. Spontaneous resolution of stenotic dissections of the bilateral vertebral arteries is extremely unusual. Serial cerebral angiography and magnetic resonance angiography are very important for monitoring the time course of changes in patients with vertebral artery dissections.

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