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T Mamiya

Publications and source records attributed to T Mamiya.

At least 91 records · Page 5Linked to original sources
PubMed1987

[Diagnosis and treatment of metastatic bone tumor in the field of radiology].

From 1973 December to 1986 September, we have experienced 2,500 cases of radiation treatment, of which 237 cases have been with bone metastasis. X-ray CT was examined on the 19 cases to detect the bone metastasis. The detective rate was 89.5% with bone scintigram alone improved to 94.7% with both bone scintigram and X-ray CT. Serum Alkali phosphatase (Al-p) were measured after and before radiation treatment on 147 cases. Values of Al-p increased on 64.6% cases measured and when values of Al-p were decreased after radiation treatment, good treatment effects were showed. Electron microscope disclosed that Al-p has existed around cell membrane of metastatic tumor cell. We considered there is a correlation between increment of Al-p in blood and contents of Al-p in bone metastatic tissues. Judgement of effects of radiation treatments were scored by three grades of pain relieving on 217 cases. Effective rate showed 87.5%. Effective rate increased by using high dose rates irradiation with small fraction. Effective cases in relieving pain had longer survival than less ones. 26 cases which could not walk due to spinal cord paresis were treated by irradiation only or irradiation with decompression surgery. Walk recovery rate was 33% by radiation treatment only, on the other hand, by treatment with decompression surgery, it was 20%. Regarding as side effect, radiation myelopathy hardly occurred about 50 Gy (conventional irradiation method). We think if longer survival time is hoped, about 50 Gy is needed.

Alkaline Phosphatase↗
PubMed1987

[Diagnosis and treatment of bone metastasis].

Diagnosis and treatments of bone metastasis were reviewed with clinical experiments in National Medical center Hospital. As for diagnosis of bone metastasis, early detection of bone metastasis was significantly improved by using bone scintigrams recently progressed. But the results of reviews suggest the possible improvements in diagnosis of bone metastasis. X-CT (X-ray Computed Tomography) for diagnosis of bone metastasis is advantages in three dimensional delineation of the extend and spread of bone lesions in bone marrow over bone scintigram. MRI (magnetic resonance imaging) has clinically been developed since 1981, does not directly represent bone structures but soft tissues in bone marrow, giving useful information concerning changes and spread of metastatic bone tumor not only inside the bone but also around it. MRI is now in technical progress and expected some improvements, could be expected in early diagnosis of bone metastasis. Regarding as treatment, we have individually to choose from radiotherapy, hormonal therapy, chemotherapy, surgical therapy according to clinical circumstances and does themselves. Radiation treatment is widely approved not only much effective in relieving the pains from bone metastasis, but also it is considered at the first choice in treatment of the spinal cord paresis by vertebral metastasis, because of frequently bringing good therapeutic effects.

Bone Neoplasms↗
PubMed1986

[Intracavitary high dose rate afterloading irradiation of inoperable malignant bile duct obstruction].

After decompression of the bile duct with PTCD, seven patients with carcinomas of the bile ducts were submitted to an intracavitary Ir-afterloading irradiation performed according to the high-dose-rate method with a Buchler device. Most of the patients were irradiated with 30 Gy in two fractions. Five patients were also exposed to percutaneous radiation with 40 to 50 Gy. Local control was achieved in six patients. One patient developed a locoregional recurrence which was possibly due to a so-called "geographic miss". In one patient a benign fibrotic stenosis of the bile duct was found at the site of most intensive irradiation. Intracavitary irradiation is very important in the treatment of malignant obstruction of bile ducts. However, there is an urgent need of research with regard to the combined method with percutaneous irradiation and to the optimum fractionation of intracavitary high dose rate irradiation.

Aged↗
PubMedDate not supplied

Quantitation of cerebral blood volume by 99mTc-DTPA-HSA SPECT.

The characteristics of technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA) as an agent for quantitation of cerebral blood volume (CBV) were examined. The radioactivity after decay correction as a percentage of the activity at 10 minutes was 84.3 +/- 1.3% at 120 minutes after the injection of 99mTc-DTPA-HSA. Radioactivity was found exclusively in plasma, with little in blood cells. The blood retention of 99mTc-DTPA-HSA is sufficient, and its use in the quantitation of CBV omits the need for centrifugation of the blood sample. CBV quantified using the tracer and a SPECT system with a single-head rotating gamma camera was 4.09 +/- 0.60 ml/100 g brain, similar to values reported previously. Two serial SPECT scans provided similar images, and the CBV values determined by the two scans were closely correlated (p < 0.001). The high reproducibility suggests that the method may be used to monitor the cerebrovascular response to drugs. It was concluded that 99mTc-DTPA-HSA has useful properties for quantitative CBV measurement and that quantitation of CBV by 99mTc-DTPA-HSA SPECT is feasible using a system with a single-head rotating gamma camera.

Adult↗
PubMedDate not supplied

A new method for monitoring the cerebrovascular response to acetazolamide using 99mTc-DTPA-HSA.

We developed a new method for monitoring the cerebrovascular response to acetazolamide using technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA). We infused 740 M Bq (20 mCi) of 99mTc-DTPA-HSA intravenously and carried out dynamic scanning of the anterior view of the head for 50 minutes. Ten minutes after the start of scanning, 1,000 mg of acetazolamide was injected intravenously. In three normal volunteers, the radioactivity in brain increased for an average of 8 minutes after the injection of acetazolamide and then remained relatively stable. The average of dilatation index [(peak count/the count just before acetazolamide injection-1)x 100] was 16.1. Our method enabled us to observe vasodilation caused by acetazolamide straight, and may be of value in assessing cerebral perfusion reserve easily and quantitatively.

Acetazolamide↗