The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform

H. Takahashi - One of the best experts on this subject based on the ideXlab platform.

  • Finite element analysis and experimental study on mechanism of brain Injury using brain model.
    2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2020
    Co-Authors: R. Ishikawa, K. Kato, M. Kubo, T. Uzuka, H. Takahashi
    Abstract:

    The aim of this study is to discuss the occurrence mechanism of the brain Injury analytically and experimentally. In this paper, first, an experimental system to do an impact experiment was presented. The pressure changes inside a brain agar phantom were measured. Second, a three-dimensional FEM model of the impact experiment was constructed. From the results of the fundamental analysis, the transmitted pressure inside the brain agar phantom could be presented. The comparison of the computer simulation and experimental results showed that the negative pressure values, same as the positive pressure occurred in the coup side region of the agar, also appeared in the Contrecoup side region of the agar. �£ .I NTRODUCTION Annually, motor vehicle crashes in the world cause over a million fatalities and over a hundred million injuries (1). The head is identified as the body region most frequently involved in life-threatening Injury. To understand how the brain gets injured during an accident, the mechanical response of the contents of the head during impact has to be known. The damage of the brain is divided into the pressure damage and the acceleration damage roughly. In the case of the both damages, there are two types of injuries, one is coup Injury caused in the direct hit region, and the other is Contrecoup Injury caused in that diagonal position. However, the occurrence mechanisms of the latter Injury have not been explained yet. Since this response can not be determined during an in-vivo experiment, numerical finite element method (FEM) is often used to predict this response. In this study, first, a system to do a basic experiment was built, and an impact experiment was conducted for the purpose of making the occurrence mechanism of the brain Injury clear. Second, a simple three-dimensional FEM model was constructed, and the fundamental analysis of the brain damage mechanism was completed. From the comparison of simulation and experimental results, it was found that computer simulation method was useful to investigate the mechanical response of the head.

  • 3-D Finite Element Analysis and Experimental Study on Brain Injury Mechanism
    2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
    Co-Authors: T. Takahashi, K. Kato, R. Ishikawa, T. Watanabe, M. Kubo, T. Uzuka, Y. Fujii, H. Takahashi
    Abstract:

    The purpose of this paper is to discuss the basic study of mechanism of brain Injury analytically and experimentally, in respect to the frequency analysis of the pressure changes. First, a three-dimensional FEM model for impact analysis was presented. The pressure changes inside a brain agar phantom and its frequency analysis were calculated. Second, an experimental system to perform an impact experiment was presented. In the impact experiments, the pressure changes inside a brain agar phantom after impact were measured. The comparison of the computer simulation and the experimental results of the impacts showed that the negative pressure, which seemed to cause the Contrecoup Injury at the Contrecoup side of a brain, also appeared in the Contrecoup side of the brain agar phantom. Finally the results of the frequency analysis of pressure changes by FFT were presented. From the results of computer simulations and impact experiments, we found similar spectrums in some frequency bands, which seemed to be the occurrence of the brain Injury.

Kiyohiro Houkin - One of the best experts on this subject based on the ideXlab platform.

  • Contrecoup Injury induced middle meningeal arteriovenous fistula detected by time of flight magnetic resonance angiography and magnetic resonance arterial spin labeling case report and review of the literature
    World Neurosurgery, 2019
    Co-Authors: Kikutaro Tokairin, Toshiya Osanai, Ken Kazumata, Ryosuke Sawaya, Kiyohiro Houkin
    Abstract:

    Background Middle meningeal arteriovenous fistula (MM-AVF) is rare; however, it will sometimes be followed by intracranial hemorrhage or progressive symptoms caused by abnormal shunt flow. Radiological examination and endovascular treatment of this condition have recently advanced; thus, we have described the pathogenesis, clinical features, and appropriate diagnostic and therapeutic management of MM-AVF. We also reviewed the reported data of the past 35 years, including 30 cases of MM-AVF. Case Description We report the case of 24-year-old man who had presented with right tinnitus who had experienced previous head trauma on the opposite side to the tinnitus ear. Time-of-flight magnetic resonance angiography and magnetic resonance arterial spin labeling findings were suggestive of MM-AVF, and catheter angiography confirmed MM-AVF with shunt flow draining into the cavernous sinus. Endovascular transarterial embolization was performed, and the MM-AVF was embolized successfully using detachable coils and n-butyl-2-cyanoacrylate. The tinnitus disappeared completely immediately after the treatment. Conclusions MM-AVF is caused, not only by coup Injury, but also by Contrecoup Injury. Time-of-flight magnetic resonance angiography and magnetic resonance arterial spin labeling are useful for detecting MM-AVF. Endovascular transarterial embolization is an effective and safe treatment.

R. Ishikawa - One of the best experts on this subject based on the ideXlab platform.

  • Finite element analysis and experimental study on mechanism of brain Injury using brain model.
    2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2020
    Co-Authors: R. Ishikawa, K. Kato, M. Kubo, T. Uzuka, H. Takahashi
    Abstract:

    The aim of this study is to discuss the occurrence mechanism of the brain Injury analytically and experimentally. In this paper, first, an experimental system to do an impact experiment was presented. The pressure changes inside a brain agar phantom were measured. Second, a three-dimensional FEM model of the impact experiment was constructed. From the results of the fundamental analysis, the transmitted pressure inside the brain agar phantom could be presented. The comparison of the computer simulation and experimental results showed that the negative pressure values, same as the positive pressure occurred in the coup side region of the agar, also appeared in the Contrecoup side region of the agar. �£ .I NTRODUCTION Annually, motor vehicle crashes in the world cause over a million fatalities and over a hundred million injuries (1). The head is identified as the body region most frequently involved in life-threatening Injury. To understand how the brain gets injured during an accident, the mechanical response of the contents of the head during impact has to be known. The damage of the brain is divided into the pressure damage and the acceleration damage roughly. In the case of the both damages, there are two types of injuries, one is coup Injury caused in the direct hit region, and the other is Contrecoup Injury caused in that diagonal position. However, the occurrence mechanisms of the latter Injury have not been explained yet. Since this response can not be determined during an in-vivo experiment, numerical finite element method (FEM) is often used to predict this response. In this study, first, a system to do a basic experiment was built, and an impact experiment was conducted for the purpose of making the occurrence mechanism of the brain Injury clear. Second, a simple three-dimensional FEM model was constructed, and the fundamental analysis of the brain damage mechanism was completed. From the comparison of simulation and experimental results, it was found that computer simulation method was useful to investigate the mechanical response of the head.

  • 3-D Finite Element Analysis and Experimental Study on Brain Injury Mechanism
    2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
    Co-Authors: T. Takahashi, K. Kato, R. Ishikawa, T. Watanabe, M. Kubo, T. Uzuka, Y. Fujii, H. Takahashi
    Abstract:

    The purpose of this paper is to discuss the basic study of mechanism of brain Injury analytically and experimentally, in respect to the frequency analysis of the pressure changes. First, a three-dimensional FEM model for impact analysis was presented. The pressure changes inside a brain agar phantom and its frequency analysis were calculated. Second, an experimental system to perform an impact experiment was presented. In the impact experiments, the pressure changes inside a brain agar phantom after impact were measured. The comparison of the computer simulation and the experimental results of the impacts showed that the negative pressure, which seemed to cause the Contrecoup Injury at the Contrecoup side of a brain, also appeared in the Contrecoup side of the brain agar phantom. Finally the results of the frequency analysis of pressure changes by FFT were presented. From the results of computer simulations and impact experiments, we found similar spectrums in some frequency bands, which seemed to be the occurrence of the brain Injury.

T. Takahashi - One of the best experts on this subject based on the ideXlab platform.

  • 3-D Finite Element Analysis and Experimental Study on Brain Injury Mechanism
    2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
    Co-Authors: T. Takahashi, K. Kato, R. Ishikawa, T. Watanabe, M. Kubo, T. Uzuka, Y. Fujii, H. Takahashi
    Abstract:

    The purpose of this paper is to discuss the basic study of mechanism of brain Injury analytically and experimentally, in respect to the frequency analysis of the pressure changes. First, a three-dimensional FEM model for impact analysis was presented. The pressure changes inside a brain agar phantom and its frequency analysis were calculated. Second, an experimental system to perform an impact experiment was presented. In the impact experiments, the pressure changes inside a brain agar phantom after impact were measured. The comparison of the computer simulation and the experimental results of the impacts showed that the negative pressure, which seemed to cause the Contrecoup Injury at the Contrecoup side of a brain, also appeared in the Contrecoup side of the brain agar phantom. Finally the results of the frequency analysis of pressure changes by FFT were presented. From the results of computer simulations and impact experiments, we found similar spectrums in some frequency bands, which seemed to be the occurrence of the brain Injury.

Zamzil Amin Ashaari - One of the best experts on this subject based on the ideXlab platform.

  • Contrecoup Injury in patients with traumatic temporal bone fracture
    Journal of Laryngology and Otology, 2011
    Co-Authors: Zamzil Amin Ashaari, Raja Ahmad Alkonee Raja Lope Ahmad, Jamalludin Ab Rahman, Norie Azilah Kamarudin, Wan L Ishlah
    Abstract:

    Objective: To study the prevalence and patterns of Contrecoup Injury in traumatic temporal bone fracture cases. Method: A prospective, cohort study was undertaken of all patients with traumatic head Injury admitted to a tertiary referral hospital in Malaysia within an 18-month period. High resolution computed tomography scans of the brain and skull base were performed in indicated cases, based on clinical findings and Glasgow coma score. Patients with a one-sided temporal bone fracture were selected and subsequent magnetic resonance imaging performed in all cases. Contrecoup Injury incidence, type, severity and outcome were recorded. Results: Of 1579 head Injury cases, 81 (5.1 per cent) met the inclusion criteria and were enrolled in the study. Temporal bone fractures were significantly associated with intracranial injuries (p < 0.001). The incidence of a Contrecoup Injury in cases with temporal bone fracture was 13.6 per cent. Contrecoup Injury was significantly associated with petrous temporal bone fracture (p < 0.01). The commonest Contrecoup Injury was cerebral contusion, followed by extradural haematoma and subdural haematoma. Conclusion: Contrecoup Injury is not uncommon in cases of temporal bone fracture, and is significantly associated with petrous temporal bone fracture.

  • Contrecoup Injury in traumatic temporal bone fracture
    2011
    Co-Authors: Zamzil Amin Ashaari, Raja Ahmad Alkonee Raja Lope Ahmad, Jamalludin Ab Rahman, Norie Azilah Kamarudin, Wan Ishlah Wan Leman
    Abstract:

    Objective : to study the prevalence and patterns of Contrecoup Injury in traumatic temporal bone fracture