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Featured researches published by Hiroyuki Uekusa.


Acta neurochirurgica | 2013

Early Cerebral Circulation Disturbance in Patients Suffering from Different Types of Severe Traumatic Brain Injury: A Xenon CT and Perfusion CT Study

Mitsuru Honda; Shigeru Sase; Kyosuke Yokota; Ryo Ichibayashi; Katsunori Yoshihara; Hiroyuki Masuda; Hiroyuki Uekusa; Jun Nomoto; Nobuo Sugo; Taichi Kishi; Yoshikatsu Seiki

INTRODUCTION Traumatic brain injury (TBI) is widely known to cause dynamic changes in cerebral blood flow (CBF). In particular, secondary brain insults have been reported to decrease CBF. The purpose of this study was to clarify the cerebral circulation in different types of TBI. METHODS Sixty-nine patients with TBI were divided into four groups, the subdural hematoma group, the contusion/intracerebral hematoma group, the diffuse axonal injury group, and the diffuse brain swelling group. In these patients, we simultaneously performed Xe-CT and perfusion CT to evaluate the cerebral circulation on post-injury days 1-3. We measured CBF using Xe-CT and mean transit time using perfusion CT and calculated the cerebral blood volume using the AZ-7000 W98 computer system. RESULTS There were no significant differences in the Glasgow Coma Scale score on arrival or the Glasgow Outcome Scale score between the groups. The patients who had suffered focal TBI displayed more significant cerebral circulation disturbances than those that had suffered diffuse TBI. We were able to evaluate the cerebral circulation of TBI patients using these parameters. CONCLUSION Moderate hypothermia therapy, which decreases CBF, the cerebral metabolic rate oxygen consumption (CMRO2), and intracranial pressure might be effective against the types of TBI accompanied by cerebral circulation disturbance. We have to use all possible measures including hypothermia therapy to treat severe TBI patients according to the type of TBI that they have suffered.


Journal of Stroke & Cerebrovascular Diseases | 2014

Hydroperoxide in Internal Jugular Venous Blood Reflects Occurrence of Subarachnoid Hemorrhage-Induced Delayed Cerebral Vasospasm

Hiroyuki Uekusa; Chikao Miyazaki; Kosuke Kondo; Naoyuki Harada; Jun Nomoto; Nobuo Sugo; Masaaki Nemoto

BACKGROUND To investigate the association between subarachnoid hemorrhage-induced delayed cerebral vasospasm (DCVS) and oxidative stress, an oxidation product, hydroperoxide, was measured in 3 specimens: peripheral arterial blood, cerebrospinal fluid (CSF), and internal jugular venous blood (IJVB). METHODS Hydroperoxide was measured using the diacron reactive oxygen metabolites (d-ROMs) test. The hydroperoxide levels were evaluated based on the rate of change in the d-ROMs test value on day 6 relative with that on day 3 (d-ROMs change rate). RESULTS The subjects were 20 patients. The d-ROMs change rate in IJVB was significantly higher in patients with DCVS on day 6 than in those without it (P < .01). When the patients were classified into the following 3 groups: Group A (no DCVS occurred throughout the clinical course); Group B (DCVS occurred, but no cerebral infarction [CI] was induced); and Group C (DCVS occurred and caused CI), the d-ROMs change rate in IJVB was the highest in Group C, followed by Group B then A (P < .01). The d-ROMs change rates in peripheral arterial blood and CSF were not related to the development of DCVS. CONCLUSIONS It was concluded that the more severe DCVS occurs and is more likely to progress to CI as the IJVB hydroperoxide level rises early after the development of subarachnoid hemorrhage.


Neurosurgery Quarterly | 2014

Ruptured Aneurysm of the Superior Cerebellar Artery Associated With Cerebellar Hemangioblastoma: A Case Report and Review of Literature

Takao Kuroki; Kosuke Kondo; Naoyuki Harada; Jun Nomoto; Hiroyuki Uekusa; Masaaki Nemoto; Nobuo Sugo; Chikao Miyazaki

Aneurysms associated with hemangioblastoma are very rare. We encountered a patient in whom an aneurysm of the distal superior cerebellar artery, the main feeding vessel of cerebellar hemangioblastoma, ruptured and caused hemorrhage. On the basis of the computed tomography findings, the superior cerebellar artery aneurysm was identified as the source of hemorrhage, and embolization using a Guglielmi detachable coil was performed in subsequent endovascular surgery. Endovascular embolization was applied to the artery feeding the tumor at 4 weeks after admission, and the tumor was removed using an occipital transtentorial approach. A favorable therapeutic outcome may be expected when using a combination of endovascular therapy and surgical craniotomy for aneurysms associated with hemangioblastoma.


Asian journal of neurosurgery | 2012

The study of systemic general circulation disturbance during the initiation of therapeutic hypothermia: Pit fall of hypothermia

Mitsuru Honda; Kyosuke Yokota; Ryo Ichibayashi; Katsunori Yoshihara; Hiroyuki Masuda; Hiroyuki Uekusa; Yoshikatsu Seiki; Jun Nomoto; Takeki Nagao; Taichi Kishi; Shigeru Sase

Aims: Neurointensive care has reduced the mortality and improved the outcome of patients for severe brain damage, over recent decades, and made it possible to perform this therapy in safety. However, we have to understand the complications of this therapy well. The purpose of our study was to determine the systemic circulation disturbance during the initiation of therapeutic hypothermia by using this continuous neurointensive monitoring system. Materials and Methods: Ten severe brain damage patients treated with hypothermia were enrolled. All patients had Glasgow Coma Scale (GCS) less than or equal to 8, on admission. Results: We verified that heart rate, cardiac output, and oxygen delivery index (DO2I) decreased with decreasing core temperature. We recognized that depressed cardiac index (CI) was attributed to bradycardia, dehydration, and increased systemic vascular resistance index (SVRI) upon initiation of hypothermia. Conclusion: Although the hypothermia has a therapeutic role in severe brain damage patients, we have to carry out this therapy while maintaining their cardiac output using multimodality monitoring devices during hypothermia period.


Journal of Stroke & Cerebrovascular Diseases | 2014

Original ArticleHydroperoxide in Internal Jugular Venous Blood Reflects Occurrence of Subarachnoid Hemorrhage-Induced Delayed Cerebral Vasospasm

Hiroyuki Uekusa; Chikao Miyazaki; Kosuke Kondo; Naoyuki Harada; Jun Nomoto; Nobuo Sugo; Masaaki Nemoto

BACKGROUND To investigate the association between subarachnoid hemorrhage-induced delayed cerebral vasospasm (DCVS) and oxidative stress, an oxidation product, hydroperoxide, was measured in 3 specimens: peripheral arterial blood, cerebrospinal fluid (CSF), and internal jugular venous blood (IJVB). METHODS Hydroperoxide was measured using the diacron reactive oxygen metabolites (d-ROMs) test. The hydroperoxide levels were evaluated based on the rate of change in the d-ROMs test value on day 6 relative with that on day 3 (d-ROMs change rate). RESULTS The subjects were 20 patients. The d-ROMs change rate in IJVB was significantly higher in patients with DCVS on day 6 than in those without it (P < .01). When the patients were classified into the following 3 groups: Group A (no DCVS occurred throughout the clinical course); Group B (DCVS occurred, but no cerebral infarction [CI] was induced); and Group C (DCVS occurred and caused CI), the d-ROMs change rate in IJVB was the highest in Group C, followed by Group B then A (P < .01). The d-ROMs change rates in peripheral arterial blood and CSF were not related to the development of DCVS. CONCLUSIONS It was concluded that the more severe DCVS occurs and is more likely to progress to CI as the IJVB hydroperoxide level rises early after the development of subarachnoid hemorrhage.


Neurosurgery Quarterly | 2013

Double Plombage Using Abdominal Adipose Tissue for Posterior Transpetrosal Approach–induced Liquorrhea

Kosuke Kondo; Takao Kuroki; Chikao Miyazaki; Naoyuki Harada; Jun Nomoto; Hiroyuki Masuda; Hiroyuki Uekusa; Masaaki Nemoto; Nobuo Sugo

Objective:To prevent posterior transpetrosal approach–induced liquorrhea, we developed a method involving the double application of abdominal adipose tissue in the subdural and epidural spaces. Materials and Methods:The method was applied to 8 patients who underwent surgery under a posterior transpetrosal approach: 4 with petroclival meningioma and 1 each with tentorial meningioma, jugular foramen neurinoma, trigeminal neurinoma, and metastatic brain tumor. The combined transpetrosal approach was used for 6 patients and the combination with the lateral suboccipital approach was used for the other 2 patients. After tumor resection, the divided dura mater of the presigmoid space was closed as follows: first, a fat mass excised from the abdominal region was divided into 2 parts, and several excisions were made in each part to flatten them. The exposed brain surface was covered with the flattened fat, and the fat margin was circumferentially inserted under the dura mater. The division was then closed by suturing the dural stumps at several sites, loading tension to some extent. Finally, the other part of the adipose tissue was spread in the epidural space in the dural-defective region for double closure inside and outside the dura mater. Results:Liquorrhea was prevented in all patients. Conclusions:It was concluded that this method is useful to prevent postoperative liquorrhea induced by a posterior transpetrosal approach.


Neurologia Medico-chirurgica | 2012

Early cerebral circulatory disturbance in patients suffering subarachnoid hemorrhage prior to the delayed cerebral vasospasm stage: xenon computed tomography and perfusion computed tomography study.

Mitsuru Honda; Shigeru Sase; Kyosuke Yokota; Ryo Ichibayashi; Katsunori Yoshihara; Yoshihito Sakata; Hiroyuki Masuda; Hiroyuki Uekusa; Yoshikatsu Seiki; Taichi Kishi


Neurologia Medico-chirurgica | 2011

Modified Three-Dimensional Brain Model for Study of the Trans-sylvian Approach

Naoyuki Harada; Kosuke Kondo; Chikao Miyazaki; Jun Nomoto; Satoru Kitajima; Masaaki Nemoto; Hiroyuki Uekusa; Masashi Harada; Nobuo Sugo


日本シミュレーション外科学会会誌 = Journal of the Japan Society for Simulation Surgery | 2011

Usefulness of preoperative three-dimensional rotational digital subtraction angiography for superficial temporal artery to middle cerebral artery bypass

Kosuke Kondo; Naoyuki Harada; Chikao Miyazaki; Hiroyuki Masuda; Masashi Harada; Hiroyuki Uekusa; Jun Nomoto; Satoru Kitajima; Masaaki Nemoto; Nobuo Sugo


日本シミュレーション外科学会会誌 = Journal of the Japan Society for Simulation Surgery | 2010

A case with recurrent giant falcotentorial meningioma resected totally by using the postoperative brain contusion

Takeki Nagao; Masaaki Nemoto; Naoyuki Harada; Kosuke Kondo; Chikao Miyazaki; Takao Kuroki; Hiroyuki Uekusa; Jun Nomoto; Nobuo Sugo; Koichi Nakajima

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Nobuo Sugo

Johns Hopkins University

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Nobuo Sugo

Johns Hopkins University

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