Kimio Yoshizato

Intramedullary epidermoid cyst in the brain stem: Case report

BACKGROUND The incidence of intracranial epidermoid cysts is between 0.2% to 1.8% of all brain tumors. They usually occur in the cerebellopontine angle or parasellar region. Intramedullary epidermoid cyst is rare and only nine cases have been previously reported. METHODS A 69-year-old woman had progressive left hemiparesis for 2 years. Computed tomography scanning and magnetic resonance imaging (MRI) revealed that there was a cystic tumor in the pons that was compressing the brain stem. A part of the tumor cyst wall and the content of the cyst were surgically removed by right subtemporal transtentorial approach. The histologic diagnosis was epidermoid cyst. After the surgery, the left hemiparesis was improved and there was no sign of the tumor growth by MRI. CONCLUSION The outcome of the previous cases with radical tumor resection was poor compared with the present case in which only a part of the cyst wall and the content were removed. Therefore, radical removal of the whole tumor may not be necessary for intramedullary epidermoid cyst of the brain stem.

Predictors of rapid spontaneous resolution of acute subdural hematoma

OBJECTIVE Acute subdural hematoma (ASDH) usually requires emergency surgical decompression, but rare cases exhibit rapid spontaneous resolution. The aim of this retrospective study was to identify factors predictive of spontaneous ASDH resolution. METHODS A total of 366 consecutive patients with ASDH treated between January 2006 and September 2012 were identified in our hospital database. Patients with ASDH clot thickness >10mm in the frontoparietotemporal region and showing a midline shift >10mm on the initial computed tomography (CT) scan were divided into two groups according to subsequent spontaneous resolution. Univariate and multivariate logistic regression analyses were used to identify factors predictive of rapid spontaneous ASDH resolution. RESULTS Fifty-six ASDH patients met study criteria and 18 demonstrated rapid spontaneous resolution (32%). Majority of these patients were not operated because of poor prognosis/condition and in accordance to family wishes. Univariate analysis revealed significant differences in use of antiplatelet agents before head injury and in the incidence of a low-density band between the hematoma and inner wall of the skull bone on the initial CT. Use of antiplatelet agents before head injury (OR 19.6, 95% CI 1.5-260.1, p=0.02) and the low-density band on CT images (OR 40.3, 95% CI 3.1-520.2, p=0.005) were identified as independent predictive factors by multivariate analysis. CONCLUSIONS Our analysis suggested that use of antiplatelet agents before head injury and a low-density band between the hematoma and inner skull bone on CT images (indicative of cerebrospinal fluid infusion into the subdural space) increase the probability of rapid spontaneous resolution.

Reporter/Functional gene transfer in rat brain.

Of the many methods and techniques for in vivo gene transfer, some have already been used in clinical trials. In most cases, genes are transferred into tissues using the infectivity of viral particles. However, viral systems have some known drawbacks (1,2). If an efficient and specific transfer method could be developed, naked plasmid DNA would be an ideal system for gene transfer. Plasmid-mediated methods would be economical and easy. Also, the transfer procedure could be easily repeated, as naked plasmid DNA has little antigenicity for the host (3,4).

Monocyte Chemoattractant Protein-1 (MCP-1) Derived from Brain Tumors: Its Significance and Clinical Application

The presence of macrophages within tumor tissue is one of the histological characteristics of malignant gliomas. Although the infiltration of macrophages suggests a possible immunological reaction by the host, the mechanisms and biological meaning of macrophage infiltration in malignant gliomas remain to be defined. A human monocyte chemoattractant protein-1 (MCP-1) was purified from the culture fluid of human glioma cell lines. MCP-1 is a 76-amino acid protein. MCP-1 is chemotactic for monocytes, but not for macrophages with an immunophenotype of the tissue-fixed, resident type. Expression and production of MCP-1 in glioma tissues and meningioma tissues were found, and there was a positive correlation between the degree of macrophage infiltration and the level of MCP-1 expression by tumor cells. Transplantation of tumor cells transfected by MCP-1 cDNA exhibited a lower growth rate than parental cells. Therefore, we speculate that tumor-associated macrophages have a suppressive effect on the growth of tumors. For clinical application of MCP-1, we measured MCP-1 concentration in cerebrospinal fluid (CSF) by enzyme-linked immunosorbent assay (ELISA). High concentration of MCP-1 was found in the CSF from malignant glioma patients with subarachnoid dissemination. Thus, measuring MCP-1 concentration in CSF may lead us to more accurate diagnosis of malignant glioma and detection of subarachnoid dissemination of the tumor cells. Further study on MCP-1 is warranted for its possible clinical applications.

Effect of Sodium Ozagrel and Nizofenone in the Treatment of Patients with Cerebral Vasospasm after Subarachnoid Hemorrhage

One hundred twenty six patients with subarachnoid hemorrhage due to ruptured intracranial aneurysm were admitted to our service between June 1988 and November 1989. Of these, 79 patients were treated with sodium ozagrel, thromboxane A9 synthetase inhibitor, or nizofenone, cerebral protector for ischemic cerebral damage. The effects were evaluated by the outcome of patients, incidence of symptomatic vasospasm and fatal vasospasm. Sodium ozagrel improved the outcome of patients and reduced the incidence of fatal vasospasm; however, it did not reduce the incidence of symptomatic vasospasm. Nizofenone was effective as well, but less so than sodium ozagrel. These results suggested that both drugs were effective in the treatment of delayed ischemic neurological deficits (DIND) due to cerebral vasospasm after subarachnoid hemorrhage.