Tsukasa Fujimoto

Showa University, Shinagawa-ku, Japan

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Publications (14)14.09 Total impact

  • Article: Different distribution of c-myc and MIB-1 positive cells in malignant meningiomas with reference to TGFs, PDGF, and PgR expression
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    ABSTRACT: We investigated the expression of transforming growth factors (TGFs), platelet-derived growth factor (PDGF), progesterone receptor (PgR), and c-myc in 20 cases of meningioma of various grades: 17 benign, 2 atypical, and 1 anaplastic. All cases of atypical and anaplastic meningioma were positive for c-myc, whereas all 17 benign meningiomas were negative for c-myc immunostaining. Expression of TGF-α, TGF-β, and PDGF-BB proteins was seen in more than 80% of the meningioma cases and was not restricted to their histological grade of meningioma. PgR was expressed mainly in benign meningiomas. Moreover, the cells expressing c-myc protein were not usually stained by MIB-1. These results indicate that c-myc does not directly work on the proliferation of meningioma cells, and even in homogeneous meningioma cells, there may be many functional variations that lead the meningioma cells to their growth.
    Brain Tumor Pathology 04/2012; 18(1):1-5. · 1.19 Impact Factor
  • Article: [Efficacy of preoperative radiation therapy in hyper-vascular solitary fibrous tumor].
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    ABSTRACT: The hyper-vascular form of solitary fibrous tumors (SFTs) is rare and there have been few therapeutic evaluations of this entity. We encountered a hyper-vascular SFT and had difficulty removing it surgically. Following radiotherapy, both tumor size and feeder vessels were reduced and we could proceed with gross total removal. A 29-year-old woman was admitted with a 1-year history of decreasing visual acuity on the right side. Magnetic resonance imaging with gadolinium enhancement showed a homogenous enhancing mass (6x5x5 cm) which expanded the superior and inferior tentorium cerebelli. The tumor was fed by the left posterior cerebral artery, bilateral middle meningeal arteries and the right occipital artery. The first operation employed an occipital transtentorial approach and a highly vascular tumor was found. Tumor resection was limited due to severe bleeding. Histologically, the tumor showed focal hypercellularity with spindle cells and numerous capillaries. Immunohistochemically, the tumor was diffusely positive for CD34 and a diagnosis of SFT, hyper-vascular subtype, was made. After the first operation, local irradiation of a total of 40 Gy was performed. Both the tumor size and vascularity decreased dramatically. At the second operation, gross total removal was able to be performed. Radiotherapy appears effective in reducing the hyper-vascular subtype of SFT and would be one possible therapy to deal with these tumors, given their propensity of excessive bleeding during initial surgery.
    No shinkei geka. Neurological surgery 03/2009; 37(2):189-94. · 0.13 Impact Factor
  • Article: [The influence on the images of computed tomography caused by the use of artificial cranial reconstructive materials].
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    ABSTRACT: Various materials have been used for cranioplasty; however, these materials frequently produce artifacts that appear when examined with conventional radiography. Computed tomography (CT), in particular, detects high density artifacts near artificial bones, which is manipulated by increased noise, and limits diagnostic performance. The purpose of this study was to evaluate the extent and shape of the artifacts due to artificial cranial bones and to consider CT imaging parameters necessary for accurate recognition of structures under the materials. Four different artificial bone materials were evaluated in this study: hydroxyapatite with 1) 40% or 2) 50% porosity, 3) titanium plate, and 4) hydroxyapatite-polymethylmethacrylate composite (HA-PMMA). CT scanning was performed with standard clinical settings. Sample specimens were placed on the right side, under the artificial bones, and CT was performed to evaluate specimen visibility. We compared the artifacts created by the four bone types listed above, and measured the CT values of those materials. With ordinary scan settings, all the artificial bones revealed high-density artifact surrounding the materials, including the inability to accurately measure specimen thickness. The upper part of the specimen in contact with the artificial bones could not be distinguished from the artifact. The CT value in the medial aspect of the artificial bones increased more than the actual CT values. Of the four artificial bone materials studied, HA-PMMA produced the fewest artifacts. Description of the structures under the artificial bones can be improved by extending the window width to approximately twice that of normal settings.
    No shinkei geka. Neurological surgery 07/2008; 36(7):607-14. · 0.13 Impact Factor
  • Article: Effect of linezolid against postneurosurgical meningitis caused by methicillin-resistant Staphylococcus epidermidis: case report.
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    ABSTRACT: A 67-year-old man who had twice previously undergone operations for a tuberculum sellae meningioma was admitted to hospital for further treatment. After the third surgical intervention, the patient developed persistent low-grade fever and impaired consciousness. Computed tomography, 1 week after surgery, showed postsurgical hydrocephalus. Cerebrospinal fluid (CSF) studies revealed high intracranial pressure (above 30 cm H2O), and increased cell count (1232/3). One week after the ventricular drainage, coagulase-negative Staphylococcus epidermidis was recovered from his CSF, and antimicrobial susceptibility results indicated that the organism was methicillin-resistant. After 14 days of intravenous vancomycin (VCM) administration failed, linezolid (LZD) was initialized intravenously, resulting in a resolution of the meningitis. After a ventriculoperitoneal shunt procedure was performed, LZD was continued orally, which resulted in a cure. CSF penetration by VCM is reported to be poor, i.e., approximately 10% of serum concentration, which may explain its lack of efficacy. In this case, the penetration of LZD into the CSF was 58.9% of the peak value and 133% of the trough value of serum concentrations. LZD must be considered one of the first-line treatments against surgical-site infection in neurosurgery caused by methicillin-resistant Staphylococci.
    Journal of Infection and Chemotherapy 05/2008; 14(2):147-50. · 1.80 Impact Factor
  • Article: Conspicuous endoscopic appearance of ventriculitis caused by coagulase-negative staphylococci.
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    ABSTRACT: To date, reports about the macroscopic appearance of ventriculitis have been rare, consisting only of a few autopsy cases. A patient in our hospital had ventriculitis caused by coagulase-negative staphylococci, and under neuroendoscopy we obtained clear findings of granular ependymitis. A 44-year-old man was admitted for disturbance of consciousness caused by progressive hydrocephalus. He had experienced subarachnoid hemorrhage (SAH) from a left vertebral dissecting aneurysm, and had subsequently received a ventriculoperitoneal shunt against post-SAH hydrocephalus. After admission, he was found to have retrograde shunt infection from peritonitis caused by cholecystitis. Coagulase-negative staphylococci were detected in cerebrospinal fluid (CSF), and the infection persisted even with intrathecal administration of gentamycin, and intravenous administration of vancomycin and arbekacin. Endoscopic rinsing was performed, and multiple small yellowish microgranulations, less than 1 mm in diameter, were observed in the lateral ventricles and the third ventricle. Rinsing of the CSF after intensive antimicrobial treatment resulted in a cure. Because there have been no reports of endoscopic observations of bacterial ventriculitis, we were unable to be certain about the origin or significance of the microgranulations. However, whether or not the microgranulations were bacterial colonies, infection did not recur during a 2-year follow-up period.
    Journal of Infection and Chemotherapy 07/2007; 13(3):177-9. · 1.80 Impact Factor
  • Article: [Spontaneous closure of dural arteriovenous fistula after performing diagnostic angiography].
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    ABSTRACT: The pathogenesis and clinical treatment of dural arteriovenous fistulas (DAVF) has been well established. However, only 15 cases of spontaneous closure of DAVFs have been reported. We describe a case of spontaneous closure of a DAVF. A 60-year-old male presented with pulsatile tinnitus. Selective cerebral angiography revealed a left posterior DAVF fed by the left occipital artery and the middle meningeal artery, which drained into the left transverse sinus and sigmoid sinus. Following the initial angiography, the patient exhibited vomiting with transient disorientation and amnesia. These symptoms, along with the tinnitus, disappeared by the following day. Seven days after the initial angiography, a second angiography was performed that revealed the complete disappearance of the DAVF. Previous reports have described a long period of closure for DAVFs following initial diagnosis. Possible mechanisms for spontaneous closure of DAVFs include the development of scar tissue or a sinus thrombosis that leads to occlusion of the DAVF In this case, the DAVF closure may have been due to a sinus thrombosis induced by sinus stenosis, since occlusion of the draining sinuses coincided with the spontaneous closure of the DAVF. In cases of non-traumatic DAVF without cortical venous reflex that do not present severe symptoms, a prudent course of treatment is necessary since there is a chance of spontaneous closure of the DAVF occuring.
    No shinkei geka. Neurological surgery 02/2007; 35(1):65-70. · 0.13 Impact Factor
  • Article: [Evaluation of cerebral blood perfusion with IVR-CT/angio system during interventional procedures].
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    ABSTRACT: An interventional-radiology computed-tomography (IVR-CT)/angio system is a combination of an angiographic unit and a CT scanner. This system allows patient's movement in and out of the two imaging units, on the same table. Since June 2003, we have applied our conventional protocol for evaluation of cerebral blood perfusion during interventional radiology (IVR) procedures. We reviewed our experience using the IVR-CT/angio system and investigated the efficacy and limitations of this technique. No complications relating to radiation exposure, contrast medium use, or IVR procedures were observed. CT perfusion was useful for detecting cerebral perfusion impairment during IVR procedures. This was helpful in deciding the postoperative management. Because patients do not need to be transported to another radiographic suite to evaluate cerebral blood perfusion, the IVR-CT/angio system is ideal for safely and simply detecting cerebral perfusion defects during IVR procedures. However, it is important to consider whether there is sufficient indication for the procedure, because radiation exposure and the amount of contrast medium use are increased if the IVR procedures become difficult.
    No shinkei geka. Neurological surgery 04/2006; 34(3):281-6. · 0.13 Impact Factor
  • Article: Dural invasion of meningioma: a histological and immunohistochemical study.
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    ABSTRACT: Meningioma usually grows and expands into the brain, but invasion into the brain parenchyma is relatively rare. Meningioma arises from arachnoid cap cells, and infiltration into dura mater is the main growth pattern of meningiomas. However, little is known about the mechanism of meningioma invasion into the dura mater. In this study, seven specimens, including dural attachments, from seven cases of meningioma were used for immunohistochemical analysis. Matrix metalloproteinase (MMP)-1, -2, -9, urokinase-type plasminogen activator (uPA), vascular endothelial growth factors (VEGF), flt-1, E-cadherin, estrogen receptor (EgR), progesterone receptor (PgR), and aquaporin (AQP)-1, -4 were used as primary antibodies. There were several patterns of meningioma invasion into the dura mater: papillary-shaped invasion with destruction of dural structure, infiltration along the fibers of the dura mater, and invasion of several tumor cell units with fibroblast infiltration. Strong immunostaining was obtained with MMP-1, followed by AQP-1 and uPA, within the invading tumor cells. Neovasculature and extravasated erythrocytes, which stained with AQP-1, were also occasionally observed around the invading tumor cells. Simpson grade II removal of meningiomas results in high recurrence rates, and the inhibition of meningioma growth via dural invasion will facilitate improved remission in many cases with meningioma. In this study, MMP-1, AQP-1, and uPA are considered to have some role in the dural infiltration of meningioma cells. The fact that AQP-1 was highly expressed at the dural attachment and invading front of meningioma may indicate that dural invasion of the meningioma may be facilitated by AQP-1-induced water flow and neovascularization.
    Brain Tumor Pathology 02/2006; 23(1):13-7. · 1.19 Impact Factor
  • Article: [Antibiotic treatment for traumatic brain injury patients without positive bacterial cultures].
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    ABSTRACT: Prophylactic administration of antibiotics is prevalent for traumatic patients including head injury, when the patients have contaminated wounds, CSF leakage, and multiple injuries. In cases with prolonged fever and inflammatory signs, other antibiotics must be selected without confirming the infections by cultures. Usually, 1st or 2nd generation cefalosporins are selected as empiric therapy for traumatic patients, but, successive antibiotics are usually selected according to the situation. In this study, we analyzed 60 cases of head injured patients with Glasgow Coma Scale under 12, in terms of the selection of antibiotics and the reasons for the antibiotic selections. CEZ > PIPC > FMOX were used for initial treatment without any culture results. The second selection was made without any positive culture results in 85.7%, and tertiary selection without culture results in 50% of the patients. CPR > CFSL > FMOX > PAPM/BP were mainly used as second selection, and IPM/CS > CPR = PIPC were mainly used as tertiary selection. In cases with traumatic brain injuries, it is important to prevent antibiotic resistances. 1) by selecting appropriate antibiotics, 2) by using antibiotics after excluding catheter related infections, 3) by not using antibiotics and performing frequent cultures when no apparent infection focuses are detected.
    No shinkei geka. Neurological surgery 02/2004; 32(2):143-9. · 0.13 Impact Factor
  • Article: Transcranial echo-guided transsphenoidal surgical approach for the removal of large macroadenomas.
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    ABSTRACT: Transsphenoidal surgery for the removal of macroadenomas has some disadvantages, including the risk of performing procedures without adequate visualization, difficulties in estimating the amount of residual tumor, and the risk of injuring major vessels. To overcome these disadvantages, the authors have developed transcranial echo-guided transsphenoidal surgery. Three patients with large macroadenomas and two patients with irregularly shaped macroadenomas were selected for this operation. In addition to standard preparations for transsphenoidal surgery, in each case the right frontal bone was trephined and an echo probe was inserted transdurally through the trephination hole. During tumor removal, brightness-mode echo images and Doppler color flow images were obtained. The echo images allowed for real-time visualization of the tumor and surrounding brain structures including major arteries and the cisterns; histological heterogeneities of the tumor could also be appreciated. The tumors were removed safely and maximal tumor removal was achieved. Transcranial echo-guided transsphenoidal surgery provides real-time visualization of tumor removal. The method enhances the safety of this surgery, maximizes the removal of the tumor, and is inexpensive.
    Journal of Neurosurgery 02/2004; 100(1):68-72. · 2.96 Impact Factor
  • Article: A case of prolactin-secreting pituitary carcinoma and its histological findings.
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    ABSTRACT: Pituitary carcinomas are very rare. The diagnosis of pituitary carcinoma is defined by evidence of craniospinal and/or systemic metastasis, rather than by histological malignancies. We report a case of prolactin-secreting pituitary macroadenoma invading the cavernous sinuses at the time of initial treatment, which later metastasized to the cerebellum, medulla oblongata, and spinal axis. The patient survived approximately nine years following the initial diagnosis of a pituitary tumor and two years following the diagnosis of metastatic disease. Histological examination of the metastatic cerebellar tumor showed an adenoma with high cellularity and hyperchromasia, but no mitoses.
    Brain Tumor Pathology 02/2004; 21(3):149-54. · 1.19 Impact Factor
  • Article: [Role of thallium SPECT for evaluating the effect of maintenance chemotherapy against malignant gliomas].
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    ABSTRACT: Thallium (Tl)-201 single-photon emission computed tomography (SPECT) is a useful tool for detecting brain tumors. In this study, we evaluated the utility of Tl-201 SPECT for determining the effect of maintenance chemotherapy with ACNU (nimustine hydrochloride)/VCR (vincristine sulfate) against malignant gliomas. The cases were comprised of 16 glioma cases; 6 astrocytomas, 2 anaplastic astrocytomas, and 8 glioblastomas. We first analyzed the correlation between Tl-201 uptake ratio and proliferative activity of the tumor, using Ki-67 immunohistochemistry in 13 cases of glioma. The uptake ratio of Tl-201 correlated with the Ki-67 staining indices (SI), and a closer correlation was obtained using Tl-201 delayed images than with the early images. We also analyzed the chronological changes of Tl-201 uptake ratio and volume of abnormal area evaluated by MRI T2-weighted imaging (MRI T2WI), in 10 cases of malignant glioma during maintenance chemotherapy. The Tl-201 uptake ratio gradually decreased with the effect of maintenance chemotherapy, and the sensitivity was superior to MRI findings. Together with MRI, Tl-201 SPECT is considered to be a useful indicator for evaluating the effect of maintenance chemotherapy against malignant gliomas.
    No shinkei geka. Neurological surgery 01/2004; 31(12):1283-9. · 0.13 Impact Factor
  • Article: Immunohistochemical analysis of reactive astrocytes around glioblastoma: an immunohistochemical study of postmortem glioblastoma cases.
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    ABSTRACT: To investigate the mechanisms of proteolysis within the glioma, and tissue reactions against glioblastoma, immunohistochemical detection both outside and inside of the tumor was performed using seven brains with glioblastoma that were obtained from autopsies. Immunohistochemistry was performed to detect vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMP)-1,-2,-9, membrane-type matrix metalloproteinase (MT-MMP), interleukin (IL)1-beta, and IL-6. The data were translated into color graphics and the localization of these proteins was analyzed. In glial cells around the tumor, GFAP, VEGF, MMP-2, and MT-MMP were strongly expressed. Moreover, IL1-beta was also expressed strongly in the glial cells at the periphery of the tumor. IL-6 was recognized outside of the tumor, but was expressed only in the swollen astrocytes and normal pyramidal cells. These data suggest that in the periphery of the tumor, tissue reconstruction processes take place with concomitant degradation of the matrix by MMP-2 and MT-MMP, as well as vascular remodeling promoted by VEGF. The fact that IL1-beta, but not IL-6, was expressed strongly in the glial cells around the tumor, may indicate that these proteins expressed outside of the tumor are not utilized for tumor growth, but may be used to guard the tumor against invasions, such as immune response.
    Clinical Neurology and Neurosurgery 06/2002; 104(2):125-31. · 1.58 Impact Factor
  • Article: Spontaneous resolution of an idiopathic cervical direct vertebral arteriovenous fistula after partial coil embolization in a patient presenting with myeloradiculopathy.
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    ABSTRACT: A 53-year old female presented with paresis of the left upper extremity. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) disclosed a single high-flow vertebral arteriovenous fistula (AVF) with vertebral artery (VA) transection. The AVF was also fed by steal flow from the contralateral VA. The left posterior inferior cerebellar artery (PICA) branched just distal to the fistula. The fistula drained into the neighboring paravertebral veins and refluxed into the intradural venous systems. The dilated drainers compressed the spinal cord. Embolization was attempted at the drainer just behind the fistula orifice using platinum coils. The fistula was still fed slightly by right VA after the embolization, but spontaneous complete obliteration was achieved after one week. The clinical symptoms and signs disappeared. Although, detachable balloon embolization is the quickest and most effective procedure to obliterate a fistula, stepwise embolization using GDC can be considered, and may avoid the normal pressure perfusion break-through phenomenon. Spontaneous obliteration of the fistula after partial embolization in our case may result from intravenous embolization just behind the fistula orifice. It may therefore be a useful approach to the embolization of an AVF to begin the embolization at the venous side of the fistula.
    Clinical Neurology and Neurosurgery 06/2002; 104(2):146-51. · 1.58 Impact Factor