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Dive into the research topics where Kazunori Tatsuzawa is active.

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Featured researches published by Kazunori Tatsuzawa.


Acta Neurologica Scandinavica | 2007

Oxygen metabolism changes in patients with idiopathic normal pressure hydrocephalus before and after shunting operation.

Junichi Miyamoto; Kazunori Tatsuzawa; Yasuo Inoue; Yoshio Imahori; Katsuyoshi Mineura

Objective –  The present study revealed the changes in cerebral oxygen metabolism before and after ventriculo‐peritoneal shunt (VPS) using 15O positron emission tomography (15O‐PET).


Skull Base Surgery | 2013

Strategies to prevent positioning-related complications associated with the lateral suboccipital approach.

Yuichi Furuno; Hiroyasu Sasajima; Yukihiro Goto; Ichita Taniyama; Kazuyasu Aita; Kei Owada; Kazunori Tatsuzawa; Katsuyoshi Mineura

The lateral positioning used for the lateral suboccipital surgical approach is associated with various pathophysiologic complications. Strategies to avoid complications including an excessive load on the cervical vertebra and countermeasures against pressure ulcer development are needed. We retrospectively investigated positioning-related complications in 71 patients with cerebellopontine angle lesions undergoing surgery in our department between January 2003 and December 2010 using the lateral suboccipital approach. One patient postoperatively developed rhabdomyolysis, and another presented with transient peroneal nerve palsy on the unaffected side. Stage I and II pressure ulcers were noted in 22 and 12 patients, respectively, although neither stage III nor more severe pressure ulcers occurred. No patients experienced cervical vertebra and spinal cord impairments, brachial plexus palsy, or ulnar nerve palsy associated with rotation and flexion of the neck. Strategies to prevent positioning-related complications, associated with lateral positioning for the lateral suboccipital surgical approach, include the following: atraumatic fixation of the neck focusing on jugular venous perfusion and airway pressure, trunk rotation, and sufficient relief of weightbearing and protection of nerves including the peripheral nerves of all four extremities.


BMC Endocrine Disorders | 2016

Neurological symptoms in a patient with isolated adrenocorticotropin deficiency: case report and literature review

Yukihiro Goto; Kazunori Tatsuzawa; Kazuyasu Aita; Yuichi Furuno; Takuya Kawabe; Kei Ohwada; Hiroyasu Sasajima; Katsuyoshi Mineura

BackgroundIsolated adrenocorticotropic hormone (ACTH) deficiency is a pituitary disorder characterized by reduction only in the secretion of ACTH. Although the underlying mechanism remains to be elucidated, numbers of cases with this entity have been increasing. We experienced a case presenting with gait disturbance necessitating differential diagnosis from idiopathic normal pressure hydrocephalus (iNPH).Case presentationA 69-year-old female with a complaint of difficulty walking and suspected to have iNPH at a prior hospital was referred to our department. For the prior three years, she had suffered from a progressive gait disturbance. Magnetic resonance imaging (MRI) revealed global ventricular dilatation. The typical features of the gait in iNPH cases were all identifiable. Neuropsychological dementia scale tests showed deterioration. However, the major feature of a disproportionately enlarged subarachnoid-space on MRI was not obvious. The patient developed progressively worsening fatigue during hospitalization. Her symptoms resembled those of hypothalamic-pituitary tumor patients. Serum ACTH and cortisol levels were low. While corticotrophin releasing hormone stress tests showed no response, other stress tests using thyrotropin releasing hormone, luteinizing hormone releasing hormone, and growth hormone releasing hormone yielded normal responses, indicating a diagnosis of isolated ACTH deficiency. We initiated corticosteroid therapy, and her gait disturbance improved promptly.ConclusionIsolated ACTH deficiency may have major significance to the differential diagnosis of iNPH. Early consideration of this entity is anticipated to facilitate making an early diagnosis.


World Neurosurgery | 2018

Unusual Presentations of Pediatric Skull Hemangiomas: Report of Two Cases

Yukihiro Goto; Hiroyasu Sasajima; Yuichi Furuno; Takuya Kawabe; Kei Ohwada; Takumi Yamanaka; Kazunori Tatsuzawa; Naoya Hashimoto

BACKGROUND Intraosseous hemangioma is a rare bone tumor, accounting for 0.7%-1.0% of all bone tumors. It can occur at any age, but only 9% of cases are younger than 10 years old. Although this tumor is usually slow-growing and clinically silent, we experienced 2 pediatric patients undergoing surgery for skull hemangioma who presented with uncommon clinical manifestations. CASE DECRIPTION Case 1 was a 9-year-old boy who presented with sudden onset of headache and was referred to our hospital. Radiologic images revealed an osteolytic oval lesion in the right parietal bone and acute subdural hemorrhage in the right cerebral hemisphere. The right parietal lesion was removed surgically. The lesion was found to have grown into the dura and to be adherent to the pia matter. The removed lesion was histologically confirmed to be a hemangioma. Case 2 was an 8-year-old girl who was referred to our hospital with an elastic mass that had been slowly enlarging for 7 years. Radiologic images revealed an osteolytic oval lesion in the right parietal bone. Surgical removal was thus planned. The lesion was found to be attached to the dura, and we removed the lesion with the surrounding bone and attached dura. Histologic examination confirmed the lesion to be a hemangioma. CONCLUSIONS Although skull hemangiomas show clinical heterogeneity, surgical removal is usually diagnostic and leads to good patient outcomes. On occasion, however, this tumor causes secondary changes in the dura, such that dural incision and dural plasty should be planned in advance of lesion removal.


Journal of neurological disorders | 2016

A Pediatric Case of Solitary Myofibroma

Yukihiro Goto; Hiroyasu Sasajima; Yuichi Furuno; Takuya Kawabe; Kei Ohwada; Kazunori Tatsuzawa; Naoya Hashimoto

A 5-year-old male was referred to our department for evaluation of a firm elastic mass at the back of his head. Clinical examination revealed no abnormalities but the local area was tender. Further clinical and radiological examinations yielded no pathological findings and no other lesions were detected. The lesion was located in the diploic layer of the left parietal bone. The inner layer of the skull intact but the outer layer showed osteolytic change. The lesion did not adhere to the dura mater. The tumor was completely removed with the surrounding bone. Histological examination revealed a mesenchymal tumor comprised of myoid spindle-shaped cells arranged in whorls between muscle cells and fibroblasts and a vascular component around the spindle cells. The final diagnosis was myofibroma. The patient recovered well after the operation and he was discharged from hospital 10 days after surgery. Clinical and radiological follow-up 6 and 12 months later showed neither recurrence of the primary lesion nor any indications of lesions at other sites. Myofibroma is a benign neoplasm composed of myoid cells with thin-walled blood vessels. This tumor, reported to have a wide range of clinical manifestations, is one of the cranial vault tumors. These tumors occur mainly in children although a few affected infants have been reported. Surgical intervention may contribute significantly to the diagnosis of solitary myofibroma and complete removal achieves good outcomes. Herein, we report a 5-year-old male with solitary myofibroma of the skull, presenting as a firm elastic mass in the left parietal bone.


Journal of Neurosurgery | 2000

Long-term follow-up study of unruptured vertebral artery dissection: clinical outcomes and serial angiographic findings

Kazuhiko Nakagawa; Hajime Touho; Toshitaka Morisako; Yasuhiko Osaka; Kazunori Tatsuzawa; Haruhiko Nakae; Kei Owada; Kazuya Matsuda; Jun Karasawa


Neurologia Medico-chirurgica | 2008

Usefulness and Limitations of Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography for the Detection of Malignancy of Orbital Tumors

Junichi Miyamoto; Kazunori Tatsuzawa; Kei Owada; Takuya Kawabe; Hiroyasu Sasajima; Katsuyoshi Mineura


Journal of Neurosurgery | 2017

Treatment of a skull-base giant cell tumor with endoscopic endonasal resection and denosumab: case report.

Yukihiro Goto; Yuichi Furuno; Takuya Kawabe; Kei Ohwada; Kazunori Tatsuzawa; Hiroyasu Sasajima; Naoya Hashimoto


Neurologia Medico-chirurgica | 2007

Metastatic Skull Tumor From Cholangiocarcinoma : Case Report

Junichi Miyamoto; Kazunori Tatsuzawa; Hiroyasu Sasajima; Katsuyoshi Mineura


Oncology Reports | 2005

Positron emission tomography elucidates transport system and tumor proliferation in meningiomas

Mamoru Murakami; Yoshio Imahori; Satoshi Kimura; Kazunori Tatsuzawa; Kei Ohwada; Yasuo Inoue; Hiroyasu Sasajima; Katsuyoshi Mineura

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Hiroyasu Sasajima

Kyoto Prefectural University of Medicine

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Katsuyoshi Mineura

Kyoto Prefectural University of Medicine

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Kei Ohwada

Kyoto Prefectural University

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Yuichi Furuno

Kyoto Prefectural University

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Yukihiro Goto

Kyoto Prefectural University

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Junichi Miyamoto

Kyoto Prefectural University

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Kei Owada

Kyoto Prefectural University

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Naoya Hashimoto

Kyoto Prefectural University of Medicine

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Kazuyasu Aita

Kyoto Prefectural University of Medicine

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