Education 【 display / non-display 】

Education 【 display / non-display 】

• 2006

  -

  2012

  Sapporo Medical University   医学部  

Research Experience 【 display / non-display 】

Research Experience 【 display / non-display 】

• 2023.04

  -

  Now

  札幌医科大学附属病院   脳神経外科   助教

• 2017.04

  -

  2018.03

  札幌医科大学附属病院   高度救命救急センター   助教

• 2022.04

  -

  2023.03

  市立函館病院   脳神経外科   医長

• 2020.10

  -

  2022.03

  帯広厚生病院   脳神経外科   医長

• 2019.10

  -

  2020.09

  砂川市立病院   脳神経外科   副医長

display all >>

Professional Memberships 【 display / non-display 】

Professional Memberships 【 display / non-display 】

• 2020

  -

  Now

  日本脳卒中の外科学会

• 2016

  -

  Now

  日本脳神経外傷学会

• 2015

  -

  Now

  日本脳神経外科学会

• 2016

  -

  Now

  日本脳神経血管内治療学会

• 2015

  -

  Now

  日本脳卒中学会

display all >>

Affiliation 【 display / non-display 】

Affiliation 【 display / non-display 】

• Sapporo Medical University   Department of Neurosurgery   助教  

Papers 【 display / non-display 】

Papers 【 display / non-display 】

• 【脳卒中外科の手術手技】Off-the-job trainingによる手術技術獲得の促進 若手術者によるSTA-MCA bypassの現状

  山岡 歩, 三上 毅, 古明地 孝宏, 能代 将平, 大瀧 雅文, 對馬 州一, 小松 克也, 金 相年, 秋山 幸功, 三國 信啓

  脳卒中の外科 ( (一社)日本脳卒中の外科学会 )  52 ( 6 ) 433 - 439  2024.11  [Refereed]  [Invited]

  Authorship：   Lead author  , Corresponding author

  　View Summary

  若手術者が経験できるSTA-MCA bypassの症例数はかぎられており,手術技術の獲得にはoff-the-job training(OJT)が重要である.自身の練習方法と手術成績から,若手術者の手術技術の獲得方法を考察した.筆者がOJTとして実施した模擬血管による端側吻合練習に関する研究である.吻合のセットアップを重視し,練習の中で各段階の右手と左手の役割を決め,無駄のない手技の順序を考え続けた.実際の手術を想定し,血管径や術野の深さを変更した.4年間で807本の練習を行い,10例12本のSTA-MCA bypassを経験した.119本の練習後に模擬血管の吻合時間が20分未満に短縮し,その後のlearning curveはなだらかになった.練習条件の変更で一時的に吻合時間が延長したが,比較的速やかに短縮した.練習本数と手術における中大脳動脈の遮断時間の間には,累乗近似曲線で高い相関を認めた(r=0.90).経験症例5例目で,遮断時間20分未満を達成した.9例目ではトラブルがあったが,遮断時間は20分未満であった.徹底した反復練習で,吻合操作のスピードが向上しただけでなく,トラブルを仮想体験することで,冷静に対処する能力が養われた.練習による遮断時間の短縮が示唆されたが,練習継続の難しさは課題である.練習方法を一定に保ちながら,飽きや慣れが生じないよう工夫し,「習慣化」を図る必要がある.(著者抄録)

• A Case of Subdural Hygroma due to a Ruptured Arachnoid Cyst in the Middle Cranial Fossa That Improved after Long-term Subdural Drainage: A Case Report and Review of the Literature.

  Ayumu Yamaoka, Shouhei Noshiro, Hiroki Akiyama, Ryota Sato, Ayaka Sasagawa, Terumasa Kuroiwa, Masafumi Ohtaki, Nobuhiro Mikuni

  NMC case report journal   11   313 - 319  2024  [Refereed]  [Domestic journal]

  Authorship：   Lead author  , Corresponding author

  　View Summary

  Arachnoid cysts have the potential to rupture, leading to the development of a subdural hygroma following minor trauma. Although surgery may be considered in cases of increased intracranial pressure (ICP) or regional neurological symptoms, the optimal approach remains unclear. We report a case of subdural hygroma due to a ruptured arachnoid cyst (SHrAC) with elevated ICP successfully treated with long-term subdural drainage for over 1 month. A 26-year-old man with persistent headache was admitted to our hospital. Magnetic resonance imaging revealed an arachnoid cyst within the left middle cranial fossa and a subdural hygroma in the left frontotemporal region. He was referred to our neurosurgery department for surgical intervention due to elevated ICP. Although burr hole surgery was initially performed, subsequent recurrence of elevated ICP necessitated the insertion of a subdural peritoneal shunt. However, the shunt was then removed following the development of postoperative meningitis, and a subdural drain was placed to control ICP. Cerebrospinal fluid (CSF) drainage gradually decreased, and the elevated ICP improved. The subdural drain was removed approximately one and a half months after drain placement. The subdural hygroma progressively reduced and completely disappeared 4 months after drain removal. The gradual reduction in the pressure difference between the arachnoid cyst and the subdural hygroma due to long-term CSF drainage and inflammation caused by meningitis may have contributed to close arachnoid membrane laceration. Although alternative approaches, such as shunt insertion and basal fenestration, should always be considered in SHrAC treatment, long-term subdural drainage can be an option.

  DOI PubMed

• Endovascular treatment of asymptomatic free-floating thrombus in the carotid artery bifurcation: a direct aspiration first-pass technique under double balloon protection.

  Ayumu Yamaoka, Kei Miyata, Satoshi Iihoshi, Nobuhiro Mikuni

  BMJ case reports   12 ( 8 )  2019.08  [Refereed]  [International journal]

  Authorship：   Lead author

  　View Summary

  Free-floating thrombus (FFT) in the carotid artery has been reported as a rare cause of acute ischaemic stroke. There are various treatment strategies, but higher risk of distal embolism may limit their applicability. A 77-year-old woman noticed right upper arm weakness. A CT angiogram revealed that a large floating thrombus had strayed across the carotid bifurcation, while another thrombus was present in the right axillary artery. As for the carotid FFT, in spite of anticoagulation therapy, the number of asymptomatic microthrombuses gradually increased on diffusion-weighted MRI. We performed endovascular therapy utilising two temporary occlusion balloon catheters and performed direct aspiration with a reperfusion catheter. The procedure was uneventful. We successfully performed a new endovascular technique for FFT in the carotid bifurcation. Our method is effective, minimally invasive and safe.

  DOI PubMed

• Traumatic Basilar Artery Entrapment without Longitudinal Clivus Fracture: A Case Report and Review of the Literature.

  Ayumu Yamaoka, Kei Miyata, Naofumi Bunya, Hirotoshi Mizuno, Hideto Irifune, Naoya Yama, Yukinori Akiyama, Takeshi Mikami, Masahiko Wanibuchi, Nobuhiro Mikuni

  Neurologia medico-chirurgica   58 ( 8 ) 362 - 367  2018.08  [Refereed]  [Domestic journal]

  Authorship：   Lead author  , Corresponding author

  　View Summary

  In blunt cerebrovascular injury, reported traumatic basilar artery occlusions have involved dissection of the basilar artery, distal embolization due to traumatic vertebral artery dissection, or entrapment of the basilar artery into the clivus fracture. To date, however, there are no reports of traumatic basilar artery entrapment without a clivus fracture. Here, we report the first case of traumatic basilar artery occlusion caused by entrapment into an originally existing bone defect. A 67-year-old man with a history of treatment for intracranial aneurysm suffered multiple traumatic injuries in a fall. On arrival at our hospital, he presented with neurogenic shock with quadriplegia. Computed tomography (CT) showed small epidural hematoma, C4-6 cervical spinous process fracture, and Th2-3 vertebral body fracture. CT angiography revealed occlusion of the basilar artery trunk. As vertebrobasilar artery dissections and clivus fracture were not observed; however, we could not elucidate the pathology of the basilar artery occlusion. On day 4, after surgery for the cervical and thoracic lesions, he exhibited consciousness disturbance. Diffusion-weighted imaging on day 5 showed hyperintensities in the brainstem and cerebellum. Basi-parallel anatomic scanning magnetic resonance imaging showed that the basilar artery, while lacking vascular wall injuries, was tethered into the clivus. Antithrombotic therapy was performed, but the patient progressed to a locked-in state. Previous head CT before the trauma revealed a bone defect already present in the clivus. We speculated basilar artery entrapment into this preexisting bone defect. We must look for basilar artery injury in trauma patients even in the absence of clivus fracture.

  DOI PubMed

• Deep learning from head CT scans to predict elevated intracranial pressure.

  Ryota Sato, Yukinori Akiyama, Takeshi Mikami, Ayumu Yamaoka, Chie Kamada, Kyoya Sakashita, Yasuhiro Takahashi, Yusuke Kimura, Katsuya Komatsu, Nobuhiro Mikuni

  Journal of neuroimaging : official journal of the American Society of Neuroimaging    2024.10  [Refereed]  [International journal]

  　View Summary

  BACKGROUND AND PURPOSE: Elevated intracranial pressure (ICP) resulting from severe head injury or stroke poses a risk of secondary brain injury that requires neurosurgical intervention. However, currently available noninvasive monitoring techniques for predicting ICP are not sufficiently advanced. We aimed to develop a minimally invasive ICP prediction model using simple CT images to prevent secondary brain injury caused by elevated ICP. METHODS: We used the following three methods to determine the presence or absence of elevated ICP using midbrain-level CT images: (1) a deep learning model created using the Python (PY) programming language; (2) a model based on cistern narrowing and scaling of brainstem deformities and presence of hydrocephalus, analyzed using the statistical tool Prediction One (PO); and (3) identification of ICP by senior residents (SRs). We compared the accuracy of the validation and test data using fivefold cross-validation and visualized or quantified the areas of interest in the models. RESULTS: The accuracy of the validation data for the PY, PO, and SR methods was 83.68% (83.42%-85.13%), 85.71% (73.81%-88.10%), and 66.67% (55.96%-72.62%), respectively. Significant differences in accuracy were observed between the PY and SR methods. Test data accuracy was 77.27% (70.45%-77.2%), 84.09% (75.00%-85.23%), and 61.36% (56.82%-68.18%), respectively. CONCLUSIONS: Overall, the outcomes suggest that these newly developed models may be valuable tools for the rapid and accurate detection of elevated ICP in clinical practice. These models can easily be applied to other sites, as a single CT image at the midbrain level can provide a highly accurate diagnosis.

  DOI PubMed

display all >>

Books and Other Publications 【 display / non-display 】

Books and Other Publications 【 display / non-display 】

• 脳神経外科臨床マニュアル

  端 和夫, 三國 信啓( Part： Contributor, 14節 呼吸管理―呼吸不全とその対策)

  丸善出版  2018.12 ISBN: 9784621303481

• 脳神経外科臨床マニュアル

  端 和夫, 三國 信啓( Part： Contributor, 50節 頭部外傷（traumatic brain injury：TBI）診療のポイント)

  丸善出版  2018.12 ISBN: 9784621303481

Awards 【 display / non-display 】

Awards 【 display / non-display 】

• 令和5年度札幌医科大学脳神経外科同門会優秀論文賞（症例報告部門）

  2024.11  

• 2nd

  2021.04   Conference on Neurosurgical Techniques and Tools   CNTT2021 顕微鏡下手術 端側吻合手技コンテスト

Presentations 【 display / non-display 】

Presentations 【 display / non-display 】

• もやもや病に対するSTA-MCA bypass術を成功させるためのoff the job trainingの工夫

  山岡 歩, 小松 克也, 西野 豪, 金 相年, 秋山 幸功, 松永 渉, 三上 毅, 三國 信啓

  日本脳神経外科学会 第83回学術集会 

  Presentation date： 2024.10

  Event date：

  2024.10

  　

  　

• Promoting the acquisition of surgical skills through off-the-job training of bypass surgery

  山岡 歩, 三上 毅, 小松 克也, 金 相年, 秋山 幸功, 能代 将平, 對馬 州一, 古明地 孝宏, 三國 信啓

  第53回 日本脳卒中の外科学会学術集会 

  Presentation date： 2024.03

  Event date：

  2024.03

  　

  　

• Analysis of the training of anastomosis in a deep corridor and learning curve

  山岡 歩, 三上 毅, 小松 克也, 秋山 幸功, 三國 信啓

  日本脳神経外科学会 第82回学術総会 

  Presentation date： 2023.10

  Event date：

  2023.10

  　

  　

• 若手脳神経外科医がバイパス術者になるための工夫―模擬血管を用いた端側吻合練習1000本からの洞察―

  山岡 歩, 小松 克也, 西野 豪, 金 相年, 秋山 幸功, 松永 渉, 三上 毅, 三國 信啓

  第54回 日本脳卒中の外科学会学術集会 

  Presentation date： 2025.03

• 救急科専門医が脳神経外科の手術手技を習得するためのルーチンワーク

  山岡 歩, 小松 克也, 金 相年, 秋山 幸功, 三上 毅, 三國 信啓

  第52回 日本救急医学会総会・学術集会 

  Presentation date： 2024.10

  Event date：

  2024.10

  　

  　

display all >>

Social Activities 【 display / non-display 】

Social Activities 【 display / non-display 】

• 脳血管障害に伴う血圧・てんかん発作管理について

  第一三共株式会社  社内研修会 

  2025.03

  　

  　

Academic Activities 【 display / non-display 】

Academic Activities 【 display / non-display 】

• Reviewer for BMC Neurology

  Peer review

  2025.02