[A Case of Bone Marrow Metastasis of Oligodendroglioma with IDH Mutation and 1p/19q Codeletion].

A 71-year-old woman was transferred to our hospital, complaining of a seizure for the first time. A tumor was detected in the right frontal lobe, and a craniotomy was performed with a partial tumor resection. The pathological diagnosis was oligodendroglioma with IDH mutation and 1p/19q codeletion, and irradiation therapy was performed. Six months later, the patient's lactate dehydrogenase(LDH)level elevated remarkably, and the fluoro-deoxyglucose-positron emission tomography/computed tomography showed abnormal uptake in multiple bone marrow locations. Bone marrow aspiration was performed, and the pathological diagnosis was oligodendroglioma metastasis. The patient was given two cycles of chemotherapy with temozolomide(TMZ), and her LDH level reduced to normal. After a few months, the LDH level elevated again, so we gave her two more cycles of TMZ;however, her LDH level did not change. Thereafter, the patient was hospitalized because of paraplegia, which started a few days prior, and right lower jaw swelling. Her CT and magnetic resonance imaging showed metastasis to the thoracic vertebrae and right mandibular bone. Irradiation therapy was performed to these locations, and the patient was given chemotherapy using nimustine(ACNU), procarbazine, and vincristine(PAV). Her LDH levels reduced temporarily, but elevated again. The patient deteriorated slowly and died 20 months after she presented with a seizure. Oligodendroglioma with extracranial metastasis is extremely rare, and this case report is the 68th report. The chemotherapy approach with TMZ or PAV/PCV may be effective against oligodendroglioma metastasis to the bone marrow.

[A Ruptured Middle Cerebral Artery Dissecting Aneurysm Operation in a 2-Year-Old Boy].

We report the case of a ruptured dissecting aneurysm in an infant. A 2-year-old boy suffered sudden headache and nausea. CT scan revealed a subarachnoid hemorrhage, and digital subtraction angiography(DSA)revealed a dissecting aneurysm(3.9mm)at a branch of the right middle cerebral artery(MCA). Eight days after onset, carotid angiography revealed enlargement of the aneurysm(up to 6.8 mm). Right frontotemporal craniotomy and aneurysm trapping with STA-MCA bypass was performed. Two years and two months later, the aneurysm recurred as assessed by magnetic resonance angiography(MRA). DSA revealed the recurrence of the aneurysm(7.8mm)proximal to the previous aneurysm and displayed development of collateral flow through leptomeningeal anastomosis between the branches of the MCA. During the second operation, the aneurysm extended to the artery branch proximal to the previous trapping. Parent artery occlusion without bypass was performed. Postoperative DSA revealed collateral flows through leptomeningeal anastomosis between the branch of the MCA and the branch of anterior cerebral artery. At the 3-year follow-up period, abnormal findings on MRI did not appear and he was healthy without any neurologic abnormalities.

[Basic principles of risk management in medical practice].

I explain the basic principles of risk management in medical practice. It is most important to understand the different meanings of the following four terms: risk, danger, crisis, and hazard. The word "risk" comes from Latin, and means food necessary to live today and tomorrow. Both medical practitioners and patients need to get over the risk in the process of diagnosis and treatment. The word "danger" means something which can harm us. It is better not to provoke such dangerous things. The word "crisis" comes from Greek, and signifies a turning point meaning life or death. Decision making is the most important at this critical point. The word "hazard" comes from old French for a game of dice. It may lead to an accident in some situations. The social welfare system has continually deteriorated in Japan. We must provide medical services in unsafe circumstances. Medical practitioners promise to do their best, but cannot guarantee a favorable outcome. It is very important to communicate with patients and family members. Doctors and nurses may experience problems with patients and their families. When problems occur regarding a patient, the management of the hospital must support the staff members concerned.

Development of a particle agglutination assay system for detecting Japanese encephalitis virus-specific human IgM, using hydroxyapatite-coated nylon beads.

Japanese encephalitis virus-specific IgM is a reliable indicator for serodiagnosis of Japanese encephalitis. A particle agglutination (PA) assay system was developed to detect anti-Japanese encephalitis virus IgM in human serum samples. The newly developed PA assay consisted of hydroxyapatite-coated nylon beads and V-bottom 96-well microplates. Hydroxyapatite-coated nylon beads were coated with Japanese encephalitis virus antigens. Japanese encephalitis virus antigen-coated, hydroxyapatite-coated nylon beads agglutinated in the IgM-captured wells when anti-Japanese encephalitis virus IgM-positive serum samples were used. A button pattern was formed at the bottom of the wells when anti-Japanese encephalitis virus IgM-negative serum samples were used. Thirty anti-Japanese encephalitis virus IgM-positive serum samples from Japanese encephalitis-confirmed cases were tested by the PA assay. All these serum samples were determined to be Japanese encephalitis virus IgM-positive. IgM titers determined by the PA assay corresponded to those determined by enzyme-linked immunosorbent assay. The titers were consistent in two independent PA assays. These results indicate that the newly developed PA assay is a reliable method for detecting anti-Japanese encephalitis virus IgM in human serum samples and that this assay will be a suitable diagnostic system especially in rural areas of Asia.