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  • Author or Editor: Hidehiro Oka x
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Satoru Shimizu, Satoshi Utsuki, Sachio Suzuki, Hidehiro Oka and Kiyotaka Fujii

✓Although the Codman-Hakim programmable valve is popular, several problems arising from its design have been described. The authors report an additional cause of shunt obstruction in the system. A 6-year-old girl who had received a ventriculoperitoneal shunt with the Codman-Hakim programmable valve system presented with worsening consciousness. The valve proved hard to flush, and emergency revision of the valve was performed. Examination of the extracted valve revealed that the pressure control cam had migrated into the outlet of the valve, thus causing the obstruction. A crack in the plastic housing surrounding the cam suggesting a past impact to the system was also revealed. These factors should thus be kept in mind as potential sources of obstruction of the valve system, especially in patients susceptible to episodes of head impact.

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Satoshi Utsuki, Hidehiro Oka, Kimitoshi Sato, Satoru Shimizu, Sachio Suzuki and Kiyotaka Fujii

Peritumoral hemangioblastoma cysts are usually composed of fibrous tissue without tumor cells. The authors describe the first case in which fluorescence with 5-aminolevulinic acid (5-ALA) was used to diagnose a hemangioblastoma tumor in a peritumoral cyst wall. A 27-year-old woman with a homogeneous, enhanced nodular lesion in the right hemisphere of the cerebellum underwent surgical treatment. After the nodular lesion was removed, the cyst region was observed with the aid of a semiconductor laser with a peak wavelength of 405 ± 1 nm, which was powered using a fiberoptic cable. The cyst region was visualized with strong fluorescence, which disappeared after tissue removal. The fluorescent cyst consisted of tumor cells. The authors conclude that fluorescence diagnosis performed using 5-ALA can inform the choice of removing hemangioblastoma cysts.

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Satoshi Utsuki, Hidehiro Oka, Takao Sagiuchi, Satoru Shimizu, Sachio Suzuki and Kiyotaka Fujii

✓ The recurrence of intracranial mature teratomas as germ cell tumors of different histological types is rarely reported. The authors describe the first case of the malignant transformation of an intracranial mature teratoma into a yolk sac tumor in a 16-year-old boy who presented with a 1-month history of anorexia and somnolence. Seven years prior to this presentation, the boy had undergone surgery for extirpation of a mature pineal teratoma. Computed tomography images obtained at his second presentation revealed a homogeneously enhanced mass within the third ventricle. The tumor was resected and the results of a histological examination were consistent with a yolk sac tumor. After resection, the patient underwent radiation therapy followed by chemotherapy with cisplatin and etoposide but died of tumor progression 15 months after his second hospitalization.

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Satoshi Utsuki, Satoshi Tanaka, Hidehiro Oka, Kazuhisa Iwamoto, Takao Sagiuchi and Kiyotaka Fujii

✓ Extracranial bone metastasis from glioblastoma multiforme (GBM) has rarely been reported in the literature, and most metastatic GBMs are multiple bone metastases. The authors describe the first case of a GBM with metastasis only to the axis. This 42-year-old man presented with a 2-month history of headache, nausea, vomiting, and disorientation. Magnetic resonance imaging demonstrated a right temporal tumor, which was diagnosed as a GBM based on tumor resection. The patient was treated using radiation (6000 cGy) and the intravenous administration of nimustine hydrochloride. Eighteen months thereafter, he experienced the sudden onset of neck pain. Magnetic resonance studies revealed a tumor in the axis that was diagnosed as GBM based on biopsy procedure.

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Satoshi Utsuki, Hidehiro Oka, Sumito Sato, Sachio Suzuki, Satoru Shimizu, Satoshi Tanaka and Kiyotaka Fujii

✓The response of nonfluorescing infiltrating tumors that had been exposed to 5–aminolevulinic acid and irradiated using a laser at a wavelength of 405 nm was analyzed intraoperatively using spectroscopy. Histological analyses demonstrated that neoplastic cells were present in the tissue region that displayed a peak at 636 nm, whereas no neoplastic cells were present in the region that exhibited only the excitation light peak. The authors conclude that the intraoperative use of laser spectroscopy can allow the diagnosis of infiltrating tumor and the detection of boundaries of the infiltrate when standard fluorescence techniques fail.

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Kimitoshi Sato, Satoru Shimizu, Satoshi Utsuki, Sachio Suzuki, Hidehiro Oka and Kiyotaka Fujii

✓ Although the Codman Hakim programmable valve (CHPV) system is popular, several problems arising from its design have been described. The authors report an additional cause of shunt failure associated with the use of the CHPV system. A 7-year-old girl who had previously undergone placement of a ventriculoperitoneal shunt with the CHPV system was admitted in a comatose state. Radiography did not demonstrate any breakage or change in the opening pressure of the valve. Manual pumping of the valve resulted in neurological improvement and shrinkage of the girl’s ventricles. However, ventriculomegaly was again observed several hours later, and an emergency valve revision was performed.

The manufacturer’s examination of the extracted valve revealed a crack on the surface of the hard plastic housing covering the valve chamber, which appeared to be suggestive of some type of blunt trauma. In addition, the flat spring that transmitted resistance from the pressure control cam to the valve ball was deformed in such a manner that it caused excessive pressure against the valve ball. Because of this deformity, the actual opening pressure in this patient had reached a maximum level of 226 mm H2O instead of the adjusted pressure of 60 mm H2O. In patients with the CHPV system whose medical history is difficult to ascertain, the possibility of damage to the valve spring and the need for a prompt revision surgery should be considered. The authors conclude that placement of the CHPV system may be contraindicated in patients with a known habit of head banging.

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Satoru Shimizu, Satoshi Utsuki, Kimitoshi Sato, Hidehiro Oka, Kiyotaka Fujii and Kimihiko Mii