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Tsuyoshi Tada

Publications and source records attributed to Tsuyoshi Tada.

At least 19 recordsLinked to original sources
PubMed2006

A case report and review of the literature.

Primary diffuse leptomeningeal gliomatosis (PDLG) is a rare central nervous system neoplasm in which gliomatous tissue is diffusely identified in the subarachnoid space with no evidence of a primary intraparenchymal tumor. A 52-year-old man presented low back pain followed by sudden unconsciousness and had also cognitive dysfunction and meningeal sign. Examinations of cerebrospinal fluid (CSF) did not show malignant cells but increased protein and pleocytosis. Magnetic resonance (MR) imaging demonstrated diffuse leptomeningeal enhancement without any source of intraparenchymal lesion. Fluid-attenuated inversion recovery (FLAIR) also demonstrated individual diffuse high intensity area in the subarachnoid space. A biopsy disclosed wide spreading of anaplastic glial cells within the leptomeninges. He died 3 months later because of disease progression despite both radiotherapy and chemotherapy. Post-mortem examination identified PDLG and several neuropathological features of glioblastoma as well. Reviewing previous cases of PDLG instructs that this entity is rare, resembles meningitis in clinical pictures, usually occurs in a relatively younger population and has more progressive clinical course than the ordinary form of malignant gliomas.

Fatal Outcome↗
PubMed2006

Presurgical factors affecting patient satisfaction with pallidal surgery in Parkinson's disease.

OBJECTIVE: To evaluate presurgical factors affecting patient satisfaction with pallidal surgery. METHODS: Forty-one parkinsonian patients who underwent unilateral pallidal surgery replied to a questionnaire on general satisfaction with the outcome of surgery graded on a five-point scale. The contribution of age, disease duration, required activity level, Unified Parkinson's Disease Rating Scale Part II activity of daily living (ADL) score and presurgical to postsurgical ADL score change to the level of satisfaction was tested. The required activity level was defined as the physical activity level which the patients required to support their families. RESULTS: Multiple regression analysis revealed that age at surgery (p = 0.02), required activity level (p = 0.005), ADL score in the on phase at surgery (p = 0.001), and ADL score in the off phase at surgery (p = 0.0001) were significant contributors to satisfaction. CONCLUSIONS: The patients who were relatively young and required higher activity levels tended to have a higher degree of satisfaction with the outcome, while patients with advanced age tended to be less satisfied, independent of symptomatic improvement after the surgery.

Activities of Daily Living↗
PubMed2006

Transient cerebellar mutism caused by bilateral damage to the dentate nuclei after the second posterior fossa surgery. Case report.

The authors report on the case of a 6-year-old boy who underwent resection of a midline cerebellar tumor. The boy was able to speak fluently after the operation. Magnetic resonance (MR) imaging showed that the right dentate nucleus had been partially removed along with the tumor, but that the left dentate nucleus remained with the residual tumor. A second operation was performed to remove the residue, after which the child suffered mutism. Three weeks post-surgery, he could only communicate through gestures. He started speaking I week later and regained normal speech 2 months after the operation. Final MR imaging revealed gross-total removal of the tumor and dentate nucleus on the injured left side. The cerebellar mutism was considered to have been caused by bilateral damage to the dentate nuclei and not by unilateral damage.

Cerebellar Neoplasms↗
PubMed2005

Intraventricular administration of hepatocyte growth factor treats mouse communicating hydrocephalus induced by transforming growth factor beta1.

Communicating hydrocephalus may occur spontaneously in elderly patients or occur as a complication of meningitis or intracranial hemorrhage, typically as a result of fibrosis along the route of cerebrospinal fluid (CSF) flow. Hepatocyte growth factor (HGF) has anti-fibrotic properties and is a promising candidate for the treatment of various fibrotic diseases. Thus, the goal of this study was to examine the effect of exogenous HGF (30 microg of human recombinant (hr) HGF intraventricularly for 7 or 14 days) in a model of hr transforming growth factor beta1-induced communicating hydrocephalus in C57BL/6 mice. HGF treatment resulted in a reduction of ventriculomegaly, as demonstrated by magnetic resonance imaging, and improved spatial memory. Further, ink passage test demonstrated improvement of normalized CSF in flow in mice receiving HGF treatment as opposed to delayed CSF flow in the hydrocephalic mice at baseline. Finally, histological examination in hydrocephalic mice undergoing HGF treatment revealed reduction of collagen fibers in the meninges and normalization of their structures. These results indicate that exogenous HGF may be of utility in the treatment of hydrocephalus in humans.

Animals↗
PubMed2005

Lack of benefit of spinal irradiation in the primary treatment of intracranial germinoma: a multiinstitutional, retrospective review of 180 patients.

BACKGROUND: The current study assessed the contribution of spinal irradiation to the treatment outcome of patients with intracranial germinoma. METHODS: Clinical data from 180 patients with intracranial germinoma, who were treated with radiotherapy and/or chemotherapy from 1980 to 2001, were collected from 6 institutions. The patients' median age was 16 years (range, 1-47 yrs), and the male-to-female ratio was 133:47. Pathologic verification was obtained in 88 patients. A solitary tumor was seen in 129 patients, and multifocal or disseminated tumors were detected in 51 patients. The median tumor size was 2.5 cm (range, 0.6-7.0 cm). Local field and/or whole brain irradiation was performed in 114 patients, and craniospinal irradiation was performed in 66 patients. Fifty-five patients were treated with chemotherapy. The median follow-up time was 89 months (range, 3-297 mos). RESULTS: Eight-year overall and event-free survival rates were 91% and 89%, respectively. The 8-year recurrence rates at the primary site, intracranial space, and the spinal space were 1%, 6%, and 6%, respectively. Cox regression analysis showed that spinal irradiation (hazard ratio, 1.050; 95% confidence interval [CI], 0.355-3.170) did not contribute to a favorable event-free survival. CONCLUSIONS: Spinal irradiation did not contribute to favorable event-free survival in patients with intracranial germinoma.

Adolescent↗
PubMed2005

A container for transporting small laboratory animals for magnetic resonance imaging.

We have constructed a simple container, consisting of a propylene tube, a High-Efficiency Particulate Aerosol (HEPA) filter and a rubber glove, for transporting small animals to magnetic resonance imaging (MRI) facilities that are located outside a pathogen-free environment. Results of pathogens analysis indicate that the container is able to prevent infection by several microorganisms. The quality of the MR images of mice and rats transported in, and imaged while in the container was satisfactory. This container can be useful for examinations that required the use of instruments located outside clean animal units, ensuring safety for both humans and animals.

Aerosols↗
PubMed2005

Diffuse encephaloventriculitis and substantial leukoencephalopathy after intraventricular administration of recombinant adenovirus.

OBJECTIVES: The use of recombinant adenovirus as a vehicle for gene transfer into ependymal cells is a potential therapeutic tool for the treatment of various neural disorders. However, gene transfer into the ependymal cells of the ventricular wall is associated with high-level expression of the transferred gene, which declines rapidly. The purpose of this study is to understand the cause of this early decline in gene expression. METHODS: Different doses of adenovirus-expressing beta-galactosidase (Ad-beta-gal) were injected into the lateral brain ventricle of C57BL/6 mice, and the brains were observed histologically and with magnetic resonance (MR) imaging for a month. RESULTS: Inoculation of the lateral ventricle with more than 1 x 10(8) viral particles (2.6 x 10(6) pfu) resulted in a rapid decline of beta -gal expression. MR imaging indicated gradual ventriculomegaly and histological analysis showed the loss of the ependymal cells from the ventricular wall, lymphocytes infiltration near the wall, degeneration of myelinated fibers and apoptosis in the external capsule. Reactive astrocytes proliferated in the external capsule 17 days following inoculation. To avoid this irreversible brain atrophy, the inoculated adenovirus should be reduced to less than 1 x 10(7) particles (2.6 x 10(5) pfu) in mice. DISCUSSION: Our results indicate the presence of a unique and diffuse immune response of the brain; therefore, the clinical use of recombinant virus for intraventricular gene transfer must be carefully evaluated.

Adenoviridae↗
PubMed2004

Spatial learning transiently disturbed by intraventricular administration of ouabain.

The presence of sodium-potassium-adenosine triphosphatase (Na+,K+-ATPase) on the surface of arachnoid cells indicates that active transport of electrolytes and water occurs there. Previously, we accidentally found that intraventricular administration of TGF-beta1 impaired rat spatial learning. Levels of Na+,K+ -ATPase were decreased in arachnoid cells with fibrosis. To characterize the role of the Na+,K+ -ATPase, Wistar rats were intraventricularly administered a total of 200 microl of ouabain, at concentrations of 10(-5), 10(-4) and 10(-3) M, for one week with an osmotic pump, and were examined with a Morris water maze. Latency for reaching the platform did not significantly differ between ouabain-administered rats and controls. Spatial learning was impaired in a dose-dependent manner. Na+,K+ -ATPase activity of arachnoid cells ceased during ouabain administration, and recovered completely three weeks after the end of ouabain administration. The present results suggest that the Na+,K+ -ATPase on the surface of arachnoid cells contributes to maintenance of rat spatial learning.

Animals↗
PubMed2004

[Treatment of craniopharyngiomas in children].

PURPOSE: The purpose of this article is to assess, in a 25-year retrospective study, the clinical outcome in children with craniopharyngioma. PATIENT AND METHODS: From 1978 to 2002, 12 children younger than 15-year-old underwent treatment with surgery and/or radiotherapy for craniopharyngioma. The clinical course and outcome were reviewed. RESULTS: The median age was 7.3 years (range, 3 to 12 years) at the time of initial surgical resection. With a mean follow-up period of 132 months (range, 29 to 255 months), 1 patient died of tumor progression due to malignant transformation at 205 months after the initial surgery and the overall outcome was good in 11 patients. Out of 12 patients 4 presented a recurrence of their tumor, 2 after an apparently gross total removal. Because of tumor recurrence, 2 received conventional radiation therapy and 3 received gamma knife radiosurgery. There was neither operative mortality nor major complication. All patients required hormonal replacement postoperatively. CONCLUSIONS: The goal in the treatment of craniopharyngiomas is to achieve total removal without morbidity. Our results compared favorably with the previous reports in the literature. MRI follow-up should be performed even in patients whose primary tumor is resected "completely". Suitable combination of open surgery, conventional radiotherapy and gamma knife radiosurgery may result in optimal functional outcome. Recovery from postoperative pituitary dysfunction can be occasionally expected.

Child↗
PubMed2003

Effects of unilateral pallidotomy on voluntary movement, and simple and choice reaction times in Parkinson's disease.

We studied the effects of unilateral pallidotomy on motor execution and reaction times in patients with moderately advanced Parkinson's disease (PD). Twelve consecutive patients (7 men, 5 women; all right-handed) underwent left-side microelectrode-guided pallidotomy. In addition to clinical rating, reaction time (RT) tests and repetitive movements of the contralesional hand/arm were carried out at baseline and 2 to 3 months after surgery while patients were on optimal medical regimens (on period). The initiation time in both simple reaction time (SRT) and choice reaction time (CRT) improved significantly after pallidotomy (P < 0.05), whereas no effect was observed on the choice processing time, which was calculated by subtracting the mean value of the onset of SRT from that of CRT. Pallidotomy resulted in significant improvement of repetitive movements such as hand pronation/supination and finger-tapping (P < 0.002, P < 0.005, respectively). Improvements in RT tests and repetitive movements suggest that pallidotomy may enhance attention and motor function. These effects are probably mediated through the pallido-thalamic-cortical neural circuitry.

Aged↗
PubMed2003

Harvesting blood stem cells from cranial bone at craniotomy--a preliminary study.

Primary brain tumors seldom infiltrate into the cranium, even if they are invasive in the central nervous system. In this study, we examined whether blood stem cells can be harvested from cranial bone at craniotomy. Bone marrow cells in cranial bone were counted in 181 craniotomy specimens after staining with hematoxylin and eosin. Marrow volume was measured in 37 specimens using three-dimensional computed tomography (CT). In 10 cases, viable cells collected from very small bone pieces at craniotomy were cultured to examine granulocyte/macrophage colony-forming units (CFU-GM). In 2 cases, bone marrow cells were practically harvested from removed bone at surgery. The weight of bone flap at craniotomy was 35.0 +/- 18.0 g. Bone flap marrow contained 1.5 x 10(9) cells/ml. CT examination showed that bone flap volume was 35.0 +/- 9.0 ml and marrow ratio was 65.1 +/- 13.5%. Thus, at craniotomy, a typical bone flap contained about 3.4 x 10(10) cells. Bone marrow cell count gradually decreased as subject age increased. The bone pieces obtained at craniotomy contained 3.1 +/- 3.4 x 10(6) cells/g, and CFU-GM count was 0.4 x 10(5) cells/g. In one case, we collected 3.4 x 10(8) cells, including 1.8 x 10(6) CFU-GM colonies. In another case, we collected 9.7 x 10(8) cells, including 4.8 x 10(6) CFU-GM colonies. These findings indicate that, at craniotomy, the number of blood stem cells in a typical bone flap is sufficient for autologous blood stem cell rescue.

Adolescent↗
PubMed2003

Internal carotid artery rotation technique to expose an aneurysm neck: technical note.

OBJECTIVE: Full exposure of a neck of an aneurysm is important to obliterate it completely. METHODS: A 51-year-old woman in whom an unruptured aneurysm projecting medially under the optic nerve was incidentally found underwent clipping surgery. The edge of the circumferentially cut distal dural ring was pulled with forceps to rotate the internal carotid artery and to expose the neck of the aneurysm. RESULTS: The neck of the aneurysm was completely obliterated under direct vision. CONCLUSION: This single, neat method exposes the neck of an unruptured paraclinoid aneurysm of the internal carotid artery.

Carotid Artery Diseases↗
PubMed2003

Double-insurance bypass for internal carotid artery aneurysm surgery.

OBJECTIVE: The aim of this article is to present the usefulness of a double-bypass method in the surgical treatment of complex internal carotid artery (ICA) aneurysms. For patients with clippable but complex aneurysms of the ICA having poor collateral circulation, bypass surgery is needed before temporary occlusion of the ICA. We propose a double bypass for safety. METHODS: The superficial temporal artery was anastomosed to the distal cortical branch of the middle cerebral artery (MCA), followed by anastomosis between the radial artery and the inferior trunk of the MCA. For patients with clippable ICA aneurysms, the radial artery was temporarily anastomosed to the inferior trunk of the MCA by raising the ipsilateral forearm to the head after the radial artery was harvested. After the aneurysm had been clipped, the anastomosed radial artery was cut close to the anastomosed site and repositioned back to the original arm. RESULTS: This double-bypass procedure was performed in two patients, and no ischemic complications related to revascularization were observed. Temporary occlusion times of the MCA for superficial temporal artery-to-MCA anastomosis and radial artery-to-MCA anastomosis were 30 and 46 minutes in one patient and 28 and 55 minutes in another. CONCLUSION: This surgical procedure, which we called "double-insurance bypass," can reduce the risk of ischemic complications associated with revascularization of the ICA.

Aged↗
PubMed2003

What is the best method for reporting tumor diameter in vestibular schwannoma?

OBJECTIVE: Various methods have been used to report the tumor diameter of vestibular schwannomas. To clarify the most appropriate method to represent the tumor volume, tumor diameters according to various measuring methods were statistically compared with the actual tumor volume. METHODS: Tumor volume was measured by three-dimensional constructive interference in steady state images in 52 unselected vestibular schwannomas. Pearson's correlation coefficient was obtained between the tumor volume and various tumor diameters, such as diameter parallel to the petrous edge (a); a pons-to-petrous diameter (b); ab, a maximum diameter of the portion in the cerebellopontine angle cistern (max CPA); a maximum diameter of the whole tumor (Max); and a diameter through an axis of the internal auditory canal (Axis). The tumors were divided into three groups on the basis of tumor volume, as follows: Group I (small, <0.5 cm(3)), Group II (medium, 0.5-2 cm(3)), and Group III (large, >2 cm(3)). RESULTS: Max and Axis correlated best with the tumor volume in Group I and correlated least with the tumor volume in Group II. Any of these measurements was acceptable in Group III tumors. The max CPA consistently revealed good correlation with the tumor volume in all three tumor groups. CONCLUSION: The max CPA measurement is the simplest and most appropriate way to represent the tumor volume in unselected tumors. Max or Axis is better only when small tumors (<0.5 cm(3) in volume) are being assessed-that is, those with a max CPA of less than 1 cm.

Adult↗
PubMed2003

Nephrotic syndrome due to primary AL amyloidosis, successfully treated with VAD and subsequent high-dose melphalan followed by autologous peripheral blood stem cell transplantation.

Primary AL amyloidosis involves vital organs from the early phase of illness, resulting in a poor prognosis. We report a patient with nephrotic syndrome due to this type of amyloidosis, who was successfully treated with two courses of VAD (vincristine, doxorubicin and dexamethasone) and subsequent high-dose melphalan (140 mg/m2) with autologous stem cell support. Following the serial chemotherapy his proteinuria improved, and M protein became undetectable in both serum and urine. To avoid the progression of primary AL amyloidosis, intensive chemotherapy should be actively used when the general status and vital organ functions are well preserved.

Amyloid↗
PubMed2003

Protective dural flap for bone drilling at the paraclinoid region and porus acusticus--technical note.

A new method was developed to avoid the risk of injury to the cranial nerves and vessels during intradural bone resection at the paraclinoid region and porus acusticus. The semicircular dural flap is pulled out with a thread over the anterior clinoid process or the porus acusticus. The flap is extended over the underlying structures with a tapered spatula to create adequate space for drilling the bone. The site for drilling was adequately exposed and bone was drilled away smoothly without damaging the underlying vessels and nerves in 10 patients with paraclinoid aneurysms and in seven patients with vestibular schwannomas. This "protective dural flap" method provides wide exposure for drilling, protects the underlying structures, and allows quick inspection during bone resection.

Brain Diseases↗
PubMed2003

Growth pattern and rate in residual nonfunctioning pituitary adenomas: correlations among tumor volume doubling time, patient age, and MIB-1 index.

OBJECT: Surgical cure can be achieved in pituitary adenomas when they are completely removed. It is controversial whether postoperative radiation therapy should be given to prevent recurrence, and whether an early reoperation should be performed for residual adenomas, because we have little information about the natural history of postoperative residual adenomas. METHODS: The residual tumor volume was serially measured in 40 nonfunctioning pituitary adenomas (NFPAs) and the tumor volume doubling time (TVDT) was calculated. Correlations between the patients' age, tumor volume, log TVDT, and MIB-1 index were examined. Other factors including the patient's sex, cavernous sinus (CS) invasion by the tumor, or presence of an intratumoral cyst were analyzed to assess their influence on the TVDT. Values are expressed as the means +/- standard deviations. Thirty-eight adenomas increased in volume and two decreased during a follow-up period ranging from 4 to 141 months (mean 52.5 months). Exponentially linear tumor growth was observed in the 38 growing adenomas regardless of the residual tumor volume, with the TVDT ranging from 506 to 5378 days (mean 1836 days). The patients' age was 57.1 +/- 15.7 years (range 15-79 years), the tumor volume at the beginning of the magnetic resonance imaging observation period was 2.5 +/- 2.2 cm3 (range 0.07-14.5 cm3), and the MIB-1 index was 0.73 +/- 0.68% (range 0.1-2.9%). There was a correlation between the log TVDT and patient age (R = 0.73), an inverse correlation between the log TVDT and MIB-1 index (r = -0.49), and an inverse correlation between the MIB-1 index and patient age (r = -0.61). A significant difference (p = 0.0001) was noted between the TVDT (1,106 days) in the 19 patients younger than 61 years of age and the TVDT (2566 days) in the 19 patients who were 61 years of age or older. There was also a significant difference (p = 0.0002) between the age (50.8 +/- 15.3 years) of the patients with rapidly growing tumors (TVDT < 1,836 days, 24 patients) and the age (69.1 +/- 7.6 years) of the patients with slowly growing tumors (TVDT> 1836 days, 14 patients). Other factors including the patients' sex, CS invasion, and intratumoral cyst formation did not affect the TVDT of residual NFPAs. CONCLUSIONS: The tumor growth rate of residual NFPAs is strongly influenced by the patient's age. The TVDT in elderly patients is much longer than that previously reported. Treatment strategies that take into consideration the natural history of residual adenomas should be established especially in the elderly population.

Adenoma↗