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Y Kamimura

Publications and source records attributed to Y Kamimura.

42 records · Page 3Linked to original sources

[Alumina ceramic (Bioceram) as the cranioplastic material--experimental study and application in cranioplasty].

External decompression is an effective treatment for acute intracranial hypertension, but the repair of cranial defect by cranioplasty is necessary sooner or later. Various materials have been used for cranioplasty, such as bone, metallic materials and methyl methacrylate. Alumina ceramic (Bioceram), which is known to be extremely compatible with tissues, has already been used in the operations of not only orthopedic and oral surgery but also neurosurgery such as transsphenoidal surgery and anterior cervical fusion. At first, we implanted pieces of ceramic and small titan shield in the parietal bone of mongrel dogs. In this experimental study, tissue compatibility and osteogenesis are investigated in each case. The new bone formation was observed macroscopically and histologically around the ceramic pieces, but there were no osteogenic changes around the titan shields. Then ceramic plates, which were designed just as patients' own bone flaps, and titan shields were used for cranioplasties after decompression surgery, and compared clinically and histologically. The ceramic plate is superior than the titan shield in its strength, tissue-compatibility and excellent fit for cranial defect compared with the titan shield. There was no tissue reaction such as subgaleal fluid collection just as seen in the application of acryl resin. We believe that Alumina ceramic (Bioceram) is a good material for cranioplasty.

Aluminum↗

[Contrast material with oxygenated Fluosol-DA, 20 for the protection against complications of catheter cerebral angiography].

Although computed tomography may change the criteria of cerebral angiography in neurosurgery, the neurosurgeon still requires angiographic confirmation of vascular anatomy at the operative sites, and catheterization for intra-luminal constructive surgery is also seeing progress. Cerebral angiography is a rather safe procedure; however, persistent serious neurological deficits and fatal complications are occasionally reported. The mechanisms of these complications are considered to be due to mechanically dislodged fragments of clots and/or atheroma, or direct endothelial damage by the catheter, contrast agents toxicity to brain tissue, anoxic neurocytologic injury due to the disturbance of the blood flow. Fluosol-DA (a type of perfluorochemical) has a potent oxygen-carrying capacity and has been safely used in humans as an artificial blood substitute. Meglumine diatrizoate (65% Angiografin) has not lost the x-ray opacification faculty in cerebral angiography by mixing with oxygenated Fluosol-DA, 20 up to 30 vol % of the latter in clinical use. In animal experiments, from 0.25 to 4 ml/kg of Angiografin-65 or Angiografin-65 with oxygenated Fluosol-DA, 20 were injected into the internal carotid artery of mongrel dogs. When 2.0 ml/kg of Angiografin-65 was injected into the carotid artery, remarkable arrhythmia was observed for 7.5 seconds. Blood pressure dropped 28.3 mmHg for 20.2 seconds; thereafter, it increased 25 mmHg in rebound for 15 seconds. Intracranial pressure increased 5 mmHg for 35 seconds, respiratory disturbance continued for 22.6 seconds. When a 20 vol % mixture of Fluosol-DA, 20 with Angiografin-65 was applied, these adverse reactions were markedly reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗