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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, 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, 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, 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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Akira Kurata, Hidehiro Oka, Taketomo Ohmomo, Hitoshi Ozawa, Sachio Suzuki, Kiyotaka Fujii, Shinichi Kan, Yoshio Miyasaka and Harue Arai

✓ This 44-year-old man with Ehlers—Danlos syndrome (EDS) Type IV presented with hemiparesis and the Gerstmann syndrome. Left carotid artery (CA) angiography revealed a dissecting aneurysm with severe stenosis located in the common CA; the lesion was successfully treated with a stent graft. The patient's clinical course after endovascular surgery was uneventful, without occurrence of megacolon. The literature for spontaneous CA dissection in EDS Type IV cases is reviewed and points for investigation and treatment are discussed.

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Satoshi Tanaka, Jiro Akimoto, Yoshitaka Narita, Hidehiro Oka and Takashi Tashiro

Object

Methylation of O6-methylguanine-DNA methyltransferase (MGMT) has been reported to be a good prognostic factor for patients with glioblastoma multiforme (GBM). To determine whether the absolute value of MGMT messenger RNA (mRNA) might be a prognostic factor and useful for predicting the therapeutic effectiveness of temozolomide, especially with regard to GBMs, the authors measured the absolute value of MGMT mRNA in gliomas by using real-time reverse-transcription polymerase chain reaction (RT-PCR).

Methods

MGMT mRNA was measured in 140 newly diagnosed gliomas by real-time RT-PCR using the Taq-Man probe. Among 73 GBMs, 45 had been initially treated with temozolomide and radiation.

Results

The mean MGMT mRNA value was significantly lower in oligodendroglial tumors than in other tumors. In the 73 GBMs, a significant prognostic factor for progression-free survival was fewer than 1000 copies/ μgRNA of MGMT mRNA (p = 0.0150). Of 45 patients with GBMs that had been treated with temozolomide and radiation, progression-free survival was significantly longer for those whose GMB had fewer than 1000 copies/μgRNA of MGMT mRNA than for those whose GBM had more than 1000 copies/μgRNA (p = 0.0090). In 32 patients with GBMs treated by temozolomide and radiation whose age was younger than 75 years and whose Karnofsky Performance Scale score was more than 70, progression-free and overall survival times were longer for those with GBMs of fewer than 5000 copies/μgRNA of MGMT mRNA than for those with GBMs of more than 5000 copies/μgRNA (p = 0.0365 and p = 0.0312).

Conclusions

MGMT mRNA might be useful as a prognostic factor and for predicting the results of therapy for GBMs treated by temozolomide. New individual adjuvant therapy based on the results of MGMT mRNA quantitation has been proposed.

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Sachio Suzuki, Akira Kurata, Taketomo Ohmomo, Takao Sagiuchi, Jun Niki, Masaru Yamada, Hidehiro Oka, Kiyotaka Fujii and Shinichi Kan

✓Application of endovascular surgery for very small aneurysms is controversial because of technical difficulties and high complication rates. The aim in the present study was to assess treatment results in a series of such lesions at one institution.

Since 1997, endovascular surgery has been advocated for very small ruptured aneurysms (<3 mm in maximum diameter) that fulfill the criterion of a fundus/neck ratio greater than 1.5. Twenty-one patients were treated, for whom the World Federation of Neurosurgical Societies classification before treatment was Grade I in 10, Grade II in two, Grade III in two, Grade IV in five, and Grade V in two. The aneurysm location was the internal carotid artery in four, the anterior communicating artery in 11, the middle cerebral artery in one, and the vertebrobasilar system in five. In all patients, endovascular surgery was performed using Guglielmi detachable coils after induction of general anesthesia. Initially, the presumed volume of the lesions was calculated for each aneurysm. Thereafter, the appropriate coil length was decided according to the volume embolization ratio, as 30 to 40%. In all attempts to obliterate aneurysms a single coil was used.

All aneurysms were completely obliterated as confirmed by postembolization angiography, without procedure-related complications. During the follow-up period only one patient needed additional coil embolization for a growing aneurysm. Final outcomes were good recovery in 15 patients, moderate disability in five, and severe disability in one.

Appropriate selection of patients and coils, and use of sophisticated techniques allow a good outcome for patients with very small aneurysms.