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T Sasajima

Publications and source records attributed to T Sasajima.

At least 109 records · Page 6Linked to original sources
PubMed1993

[Results of arterial reconstruction in Buerger's disease].

One hundred and eight bypass operations for Buerger's disease were performed between November 1976 and August 1990. The bypass procedures, prostheses, cumulative patency rate and the influence of smoking on the results were discussed. Five-year cumulative patency rate of Aorto-femoral bypass was 88.2%. Aorto-femoral bypass should be always indicated as a standard procedure for the iliac lesion in Buerger's disease, because the patency rate was very low in aorto-iliac bypass group or ilio-femoral bypass group. Five-year cumulative patency rate of infrainguinal bypass using autogenous vein was 64.8%, and that in the patients who quit cigarette smoking was as high as to 73.3%. We should use autogenous vein as much as possible for infraiguinal bypass and discontinuance of cigarette smoking is considered to be one of the important factors to improve the patency rate in Buerger's disease.

Adult↗
PubMed1993

[Extensive bowel infarction caused by intraaortic balloon pumping].

Two cases of an extensive bowel infarction occurred during Intraaortic Balloon Pumping (IABP) are reported. In the first, an acute myocardial infarction was seen suddenly on the seventh postoperative day following arterial reconstruction of the right lower leg and his condition required IABP support. Five day after beginning of IABP, severe symptoms suggesting peritonitis appeared, and laparotomy revealed an extensive infarction of small bowel and sigmoid colon. In the second, the patient required IABP support for weaning from cardiopulmonary bypass after completion of coronary artery bypass grafting. A severe peritonitis was caused by an extensive infarction of small and large intestine during two days of IABP support. Cholesterol emboli were found in the small bowel arteries of the case 1 at microscopic examinations of the autopsy specimen. Both patients died of cardiopulmonary failure and renal failure respectively, though necrotic intestine were resected. Circulatory support using IABP should not be selected, when a patient has severe arteriosclerotic lesions of the aorta.

Angina, Unstable↗
PubMed1993

[A case report of a chronic traumatic thoracic aneurysm].

A successful experience of a case with chronic traumatic thoracic aneurysm is reported. A 51-year-old male patient had a history of a blunt chest trauma in a traffic accident one and a half year ago. He developed gradual hoarseness because of the recurrence nerve paralysis. Computed tomography and angiography revealed a saccular aneurysm at thoracic descending aorta. It was treated with direct closure of the tear under partial clamp of the aorta. His postoperative course was excellent. He is doing well two years after operation.

Accidents, Traffic↗
PubMed1992

Effects of radiotherapy determined by 11C-methyl-L-methionine positron emission tomography in patients with primary cerebral malignant lymphoma.

Two cases of histologically proven primary cerebral malignant lymphoma were examined serially with positron emission tomography (PET) using 11C-methyl-L-methionine (11C Met). Lesions delineated by 11C Met accumulation extended beyond enhancing areas on either X-ray computed tomography (CT) or magnetic resonance imaging. High uptake of 11C Met accurately showed biologically active and residual tumours, at a time when disappearance of a contrast-enhancing lesion on CT seemed to indicate involution. PET provides valuable information on the extent of tumour and assessment of radiotherapy in malignant lymphoma.

Aged↗
PubMed1992

Radiation-induced bilateral cystic frontal lobe necroses demonstrating a fluid-blood level--case report.

A 41-year-old male developed radiation-induced bilateral cystic frontal lobe necroses after irradiation for an olfactory neuroblastoma. Computed tomography (CT) and magnetic resonance (MR) imaging revealed the lesions, one containing a fluid-blood level on CT scans and niveau formation on MR images. It was proved to be a coagulated hematoma within the cyst at surgery. Such a fluid-blood level in a radiation-induced cyst has never been reported, although hemorrhage frequently accompanies delayed radiation necrosis. Positron emission tomography with multiple tracers may be useful in differentiating cerebral radiation necrosis from tumor recurrence, because of absence of abnormal tracer accumulation.

Adult↗
PubMed1991

Innovative approach in the diagnosis of gliomatosis cerebri using carbon-11-L-methionine positron emission tomography.

A case of gliomatosis cerebri was studied with positron emission tomography (PET). Carbon-11-L-methionine (11C-Met) accumulated in the diffusely infiltrative tumorous area more widely and accurately than the lesion detected by conventional x-ray computerized tomography (CT) or magnetic resonance (MR) imaging. Autopsy findings three months after the time of the PET study showed good anatomical correspondence between the extent of densely aggregated tumor cells and the region with high uptake of 11C-Met. PET may offer an innovative approach in the delineation of gliomatosis cerebri, which has not been clearly recognized by CT or MR.

Adult↗
PubMed1990

Amino acid study of cerebral gliomas using positron emission tomography--analysis of (11C-methyl)-L-methionine uptake index.

Sixteen patients with gliomas (7 low grade, 9 high grade) were examined using positron emission tomography (PET) with intravenous administration of 22.2 MBq/kg (0.6 mCi/kg) of (11C-methyl)-L-methionine (C-11 Met). The tracer uptake in regions of interest was calculated on PET images taken 45 minutes after injection; the uptake index was represented as a percentage of the total count in the arterial blood summed over 45 minutes. C-11 Met uptake indices in the tumors ranged from 0.020 to 0.041% with a mean of 0.032% for the low-grade gliomas and from 0.013 to 0.044% with a mean of 0.036% for the high-grade gliomas. These indices significantly increased as compared with those in the contralateral gray matter (0.008-0.032% with a mean of 0.023%; p less than 0.01 vs. low-grade gliomas, p less than 0.001 vs. high-grade gliomas). In the low-grade gliomas, C-11 Met PET images clearly depicted the existence and even the extent of the tumors, although x-ray computed tomography (CT) did not always distinguish tumoral lesions. In the high-grade gliomas, the areas of tracer accumulation regionally extended to peritumoral low density on CT scans, where malignant tumor cell infiltration was proved by operative and follow-up CT findings. C-11 Met may be a useful radiopharmaceutical for differential diagnosis of gliomas, and the accuracy of tumor localization will give us a better rationale in therapeutic strategies for surgery and radiation therapy of gliomas.

Adolescent↗
PubMed1990

[Positron emission tomography (PET) of an invasive ACTH-producing pituitary adenoma].

We report a case of large, invasive ACTH-producing pituitary adenoma with PET study. In CT scans, an intra- and supra-sellar mass diminished after replacement therapy for primary hypoadrenalism. Two years and seven months later, the tumor grew and extended into the neighboring structures. 11C-methionine accumulated markedly in the tumor, and depicted the lateral and dorsal extension.

Adenoma↗
PubMed1990

[Results of the treatment of intracranial germ cell tumors].

Presented is a retrospective study of 20 patients with intracranial germ cell tumors who the authors have treated during past 10 years. The cases among these patients included thirteen germinomas, three teratomas, two embryonal carcinomas, and two malignant teratomas. A ventriculoperitoneal shunt was installed in 15 cass and the tumor was surgically removed in four cases. All cases were irradiated with 33 to 61 Gy; in 18 cases, more than half of the total dose was delivered to the whole brain, and in 9 cases, spinal irradiation was given because of a verified CSF dissemination. Chemotherapy was the regimen for four cases. The tumor responded to therapy in 16 (84%) of 19 evaluable cases. Overall, the median and five year survival were 102 months and 83%, respectively. The survival rate was found to vary between the benign group (germinoma, teratoma) and the malignant group (embryonal carcinoma, malignant teratoma, germinoma with STGC) (p less than 0.01).

Adolescent↗
PubMed1990

[Positron emission tomography (PET) study in patients with meningiomas].

Regional hemocirculation and metabolism were evaluated in five patients with meningiomas using positron emission tomography (PET). Histological diagnoses were: two cases of meningotheliomatous type, one hemangiopericytic type, one fibroblastic type, and one transitional type. Regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), and metabolic rates of oxygen (rCMRO2) and glucose (rCMRG1) were measured with 15O2, C15O. 15O2, and 18F-fluorodeoxyglucose tracers. For the quantitative analysis, regions of interest were delineated on tumors, the peritumoral region, and the contralateral gray matter in comparison with age-corresponding 5 malignant gliomas and 5 normal volunteers. Tumor hemocirculatory parameters (rCBF: 57.2 +/- 22.6 ml/100 ml/min, rCBV: 7.95 +/- 3.27 ml/100 ml, mean + SD, n = 5) were markedly higher than those of the contralateral gray matter (p less than 0.05 by a Student-t test). The high values were consistent with angiographic findings of tumor staining and with abundant tumor vessels demonstrated by pathological examination. rCMRO2 was 2.15 +/- 0.80 ml/100 ml/min, which were comparable to those of the contralateral gray matter. Tumor rCMRG1 showed 4.76 +/- 2.37 mg/100 ml/min; the values of two cases were similar to the respective gray matter. The raised metabolic rate (rCMRO2/rCMRG1) therefore suggests rather aerobic glycolysis as compared with gliomas. Low rOEF (0.26 +/- 0.16) reveals an excessive blood flow beyond oxygen demand of the tumor. In the peritumoral regions, rCBF and metabolism fell slightly but rOEF reached a level similar to the contralateral gray matter, possibly due to hemocirculatory stasis caused by intracranial hypertension; in contrast, an unmatched reduction of rCBF and rCMRO2 implies tumor cells infiltration in gliomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[A case of perianeurysmal fibrosis treated by the thrombo-exclusion technique].

A very rare case of perianeurysmal fibrosis was presented. A 65-year old man was admitted with the complaint of abdominal pulsatile mass and intermittent claudication of right lower limb. Aortography revealed fusiform, calcified aneurysm of the infrarenal abdominal aorta and severe stenosis of right common iliac artery. CT scan demonstrated a soft tissue density structure around the aortic aneurysm which was enhanced after contrast medium injection. At surgery, the aneurysm had a thick, firm, smooth wall which was shiny white in appearance and adherent perianeurysmal fibrosis was marked. In order to avoid injury to surrounding tissue such as the duodenum or vena cava, thrombo-exclusion method was chosen. Histological examination of the aneurysmal wall showed fibrous tissue infiltrated with mononuclear cells such as lymphocytes and plasma cells. The postcontrast enhancement of aortic wall and perianeurysmal sheet disappeared on CT on the post-operative 57th day and no recurrence has been observed.

Aged↗
PubMed1989

[Prognostic significance of regional blood flow, blood volume, oxygen extraction fraction, and metabolic rates of oxygen and glucose as measured by positron emission tomography in patients with gliomas].

We tested clinical significance of hemocirculatory and metabolic values and ratios as determined by positron emission tomography (PET) in twenty-three patients with cerebral gliomas. Regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), and metabolic rates of oxygen (rCMRO2) and glucose (rCMRGl) were measured prior to treatment using PET with 15O2, C15O, 15O2, and 18F-fluorodeoxyglucose tracers. For the quantitative analysis, regions of interest were delineated on tumor regions including peak activity, the contralateral gray and white matter. The regional values and the ratios of tumor/gray matter and tumor/white matter were compared to performance status (PS) according to the five functional grades system which are defined by the Japan Society for Cancer Therapy, tumor progression-free time (PFT), survival time (ST) from the time of the PET study, regardless of type of therapy. As with rCMRGl, the tumor values and the ratios of tumor/gray matter and tumor/white matter correlated significantly with PS (tumor/gray: p less than 0.05, tumor/white: p less than 0.01). Both the gray rCBF and the tumor/gray rCBF ratio had close relation with PS and/or PFT (p less than 0.05). The gray matter rCMRO2 and the tumor/gray matter rCMRO2 ratio related significantly (gray matter: p less than 0.01, tumor/gray: p less than 0.05) to each clinical parameter of PS, PFT, and ST. These indicate that values and ratios as determined by PET can be useful in predicting the prognosis of glioma patients.

Adolescent↗
PubMed1989

Sequential PET studies in neuro-Behçet's syndrome.

A case of neuro-Behcet's syndrome is presented with sequential positron emission tomography (PET) studies. Regional cerebral blood flow (rCBF) and oxygen consumption (rCMRO2) were decreased in the brain lesion; however, on follow-up studies 3 months after steroid therapy rCBF and rCMRO2 had increased in the lesion, which demonstrated the reversibility of this disease. Such monitored improvement may accurately reflect the early stage of the disease and its response to steroid therapy.

Behcet Syndrome↗
PubMed1989

[Radiochemotherapy-related changes in the brain parenchyma of glioma patients evaluated repeatedly by C15O2, C15O, 15O2, and 18F-fluorodeoxyglucose (FDG) PET].

The aim of this study was to evaluate effects of radiochemotherapy on blood flow and metabolism using C15O2, C15O, 15O2, and 18F-fluorodeoxyglucose positron emission tomography (PET). Conventional, external radiotherapy (180-200 cGy/5 fractions/week) using 60Co or a 10 MV linear accelerator was given in conjunction with chemotherapy of nimustine hydrochloride (ACNU) and tegafur (FT-207) in eight patients with gliomas. Regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), oxygen consumption (rCMRO2), and glucose consumption (rCMRG1) were longitudinally examined before the treatment, and at an early stage (within one month) and a late stage (three to thirty-one months with a mean of 12 months) after radiochemotherapy. Contralateral gray and white matter to the tumor was selected as regions of interest (ROIs), because these portions were irradiated with larger doses compared to other brain parenchymal regions through parallel opposing fields. Maximum doses to the ROIs varied between 20 and 61 Gy. Calculated as a function of time-dose-fractionation, nominal standard doses (NSD) ranged from 566 to 1729 ret, and 344 to 1062 neuret; equivalent doses (ED) equaled 432 to 1327 rads. At the early stage, rCBF and rCBV increased in the contralateral gray and white matter; gray matter rOEF decreased significantly (p less than 0.05 by a paired-t test) from that of the pretreatment study, probably due to decompression of the tumor bulk and radiochemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Analysis of regional blood flow, blood volume, oxygen and glucose metabolism in heterogeneous parts of untreated high grade gliomas using positron emission tomography (PET)].

A high resolution positron emission tomography (PET), HEADTOME III, has enabled us to visualize heterogeneous parts, i.e. viable, necrotic, and edematous portions in malignant gliomas, and to quantify regional hemocirculation and metabolism of the tumors using 15O and 18F-fluorodeoxyglucose tracers. Hemocirculatory and metabolic indices of regional cerebral blood flow (rCBF), blood volume (rCBV), oxygen extraction fraction (rOEF), oxygen consumption (rCMRO2) and glucose consumption (rCMRGl) were studied in eight patients with untreated malignant gliomas. Regions of interest (ROIs) in PET images were focused on lesions corresponding to contrast enhancing areas, central low density areas of the tumors, and peritumoral low density areas in CT scans. In the viable portion of the gliomas, rCBV (5.20 +/- 1.18ml/100ml, mean +/- SD, n = 8) was significantly higher than that of the contralateral gray matter (p less than 0.05), which is suggestive of high vascularity; rOEF (0.36 +/- 0.16) and rCMRO2 (1.66 +/- 0.45ml/100ml/min) values markedly decreased (p less than 0.05, p less than 0.01). On the other hand, rCBF (36.3 +/- 13.0ml/100ml/min) and rCMRGl (5.94 +/- 1.15mg/100ml/min) were similar to that of the contralateral gray matter. A relative dissociation between oxygen and glucose metabolism indicates anaerobic glycolysis in the energy metabolism of malignant gliomas. In the central low density area, rCBF, rCBV, rOEF, rCMRO2, rCMRGl values decreased significantly from the viable portion and the contralateral gray matter. rOEF was markedly reduced in the central low density area as compared with that of the peritumoral low density area. The rOEF reduction indicates that oxygen metabolism of gliomas is the first to fail, accompanied by autoregulatory impairment of vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Changes in the (11C-methyl)-L-methionine uptake index in gliomas following radiotherapy].

We have studied changes in the (11C-methyl)-L-methionine (C-11 Met) uptake index in six glioma cases subsequent to radiotherapy, using positron emission tomography (PET) to evaluate the effects of radiotherapy on the amino acid metabolism of the tumor. The uptake index of the tumor represented as a percentage of the total count in the atrial blood recorded during a period of 45 min, showed an average of 0.037% and 0.039% prior to and within two months after the therapy, respectively. Out of three cases where a fall in the index was seen, two cases showed tumor regression in the size of the contrast enhanced lesion measured by CT; all three cases had a relatively long period of clinical and neurological amelioration. However, following a short period of clinical improvement, the other three patients with a rise in the index showed no change or tumor progression on CT. These findings indicate that changes in the C-11 Met uptake index can be a sensitive and precise indicator for evaluating the effect of radiotherapy on gliomas.

Adult↗
PubMed1984

[Preserved human umbilical cord vessel as a small caliber vascular substitute: experimental and clinical study].

The author has studied glutaraldehyde stabilized human umbilical cord vessels (PHUV) both experimentally and clinically since Nov. 1976. The experimental findings showed that the PHUV is not organized and its patency depends on the blood compatibility of the fibrin net and blood flow. The histologic examination of the graft wall revealed a slight inflammatory response consisting of macrophages and occasional foreign body giant cells around the Dacron mesh but with very little reaction in the umbilical vein itself. Clinically, 72 reconstructions using Biografts were performed in 52 cases with peripheral arterial occlusions. These consisted of 14 femoropopliteal (FP) bypasses above the knee, 26 below the knee, 10 femorotibial or peroneal and 16 other miscellaneous procedures including aorto-femoral and extra-anatomic bypasses. The cumulative patency rate at 5 years was 63.0% for the total group, 62.9% for the F-P group and 20% for the femoro-tibial or peroneal group. Early failure was thought to be related to technical factors in most instances. The majority of the late failures were due to intimal hyperplasia at the anastomotic sites. Although it is reasonable to employ a Biograft at the popliteal level because of the encouraging results in its clinical use, it is important to study the mechanism of the intimal hyperplasia at the anastomotic sites in order to attain excellent long term results.

Aged↗