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E Tsukamoto

Publications and source records attributed to E Tsukamoto.

At least 55 records · Page 3Linked to original sources
PubMed1998

Thallium-201 scintigraphy to predict therapeutic outcome of iodine-131 therapy of metastatic thyroid carcinoma.

UNLABELLED: We studied the relationship between 201Tl uptake and the efficacy of radioiodine therapy in thyroid carcinoma. METHODS: Forty-four patients with metastases of well-differentiated thyroid carcinoma received 201Tl scintigraphy within the 2 mo before their initial 131I therapy. Patients were classified into two groups according to the tumor-to-background (T/B) ratio on the late 201Tl scan: high 201Tl uptake (T/B > or = 2.1) and low 201Tl uptake (T/B < 2.1). The therapeutic outcome was judged by the percent reduction in the tumor diameter at 6 mo after the treatment. The treatment was defined as effective when the tumor showed more than 50% reduction in the tumor diameter. The patients in whom radioiodine was ineffective were followed up to determine if the tumor showed further growth. RESULTS: Of the 44 patients, 25 had high 201Tl uptake and 19 had low 201Tl uptake. The therapy was effective in 15 patients and was ineffective in 29. All the patients in whom radioiodine was effective had low 201Tl uptake. On the other hand, 25 of 29 patients in whom radioiodine was ineffective had high 201Tl uptake. Eight patients, in whom radioiodine was ineffective despite good 131I uptake, had high 201Tl uptake. There were no significant differences in the positive predictive value and the negative predictive value for effective treatment between 201Tl scintigraphy and therapeutic dose 131I scintigraphy. Among the 25 patients in whom radioiodine was ineffective and who had high 201Tl uptake, the tumor diameter increased in 7 (28%). However, none of the tumors with low 201Tl uptake increased in size during the follow-up period. CONCLUSION: Thallium-201 scintigraphy has a high predictive value for the efficacy of radioiodine therapy in metastatic thyroid carcinoma. Thus, it is helpful in determining the indication for radioiodine therapy and it seems to be an adjunct to tracer dose 131I scintigraphy.

Adenocarcinoma, Follicular↗
PubMed1998

[Comparison of single sample methods for determination of plasma clearance using 99mTc-MAG3].

We compared relationship among three single blood sampling methods which have been proposed for determination of plasma clearance with 99mTc-MAG3. Russell's and Bubeck's algorithms were employed for 48 adults (average age: 53 years) and Bubeck's and Piepsz's algorithms were used in 9 children (average age: 5.8 years). Three methods showed very high correlation among them. However, Russell's and Piepsz's methods were about 1.4 times higher than Bubeck's method in calculating plasma clearance of 99mTc-MAG3. The present study indicates that three methods discussed here are useful for the determination of plasma clearance with 99mTc-MAG3. In addition, Bubeck's method may be preferable as a reference for single plasma sampling method because of common application to adults and children.

Adolescent↗
PubMed1997

Thallium-201 single photon emission computed tomography as an indicator of prognosis for patients with lung carcinoma.

BACKGROUND: The uptake of thallium-201 (T1-201) in malignant tumors is associated with malignant potential (metastatic potential and proliferative activity). The grade of accumulation of T1-201 in malignant tumors may provide information regarding prognosis. METHODS: A T1-201 single photon emission computed tomography was conducted 120 minutes after intravenous injection of 111 megabecquerel of T1-201 chloride. The authors calculated the uptake ratio to evaluate the degree of T1-201 uptake in the primary tumor. This ratio was compared with survival time and other prognostic factors. RESULTS: The authors studied 152 patients (125 men and 27 women). The group of patients with the low T1-201 uptake ratio survived longer than the group of patients with the high T1-201 uptake ratio (median survival, 58 weeks vs. 33 weeks; P = 0.0138 by the log rank test). The multivariate analysis confirmed that the T1-201 uptake ratio was an independent prognostic factor for survival. CONCLUSIONS: These results suggest that the T1-201 uptake ratio provides independent and objective prognostic information for patients with lung carcinoma.

Adult↗
PubMed1997

Sequential change of BMIPP uptake with age in spontaneously hypertensive rat model.

UNLABELLED: Changes in myocardial perfusion and metabolism are often associated with myocardial hypertrophy, but there are few reports describing the serial assessment of fatty acid metabolism in hypertrophic myocardium. The aim of this study is to assess fatty acid metabolism serially in hypertrophic myocardium in spontaneously hypertensive rats (SHR) with 125I-BMIPP, a branched fatty acid analog. METHODS: SHR and Wistar-Kyoto rats (WKY) as the control were divided into 4 groups (12, 15, 18 and 51 weeks after birth). The heart was extracted 10 minutes after intravenous injection of 125I-BMIPP and 201Tl at the same time. The accumulation of each radiotracer in the myocardium was counted with a well gamma counter. In addition, 125I-BMIPP uptake was corrected by 201Tl uptake (B/T). RESULTS: The heart weight/body weight ratio was significantly higher in SHR than that in WKY (p < 0.001). In SHR, this ratio increased up to 18 weeks (12 weeks; 0.266 +/- 0.005, 18 weeks; 0.281 +/- 0.006: mean +/- SE, p < 0.05). The 125I-BMIPP uptake tended to be significantly reduced in SHR (12 weeks; 2.373 +/- 0.212, 18 weeks; 1.380 +/- 0.047; mean +/- SE, p < 0.05). Such a difference in BMIPP uptake was more evident when BMIPP uptake was corrected by Tl uptake (B/T), but no regional difference or heterogeneity of BMIPP distribution was observed in the hypertrophic myocardium in SHR. CONCLUSION: A change in fatty acid metabolism with age was observed in association with myocardial hypetrophy in this hypertensive rat model, which was well demonstrated with 125I-BMIPP and 201Tl.

Aging↗
PubMed1997

Incidence and clinical significance of linear defects ascribed to interrenuncular septa on 99Tcm-DMSA SPET.

99Tcm-dimercaptosuccinic acid (99Tcm-DMSA) planar and single photon emission tomographic images from 100 children were reviewed to analyse whether linear defects corresponding to anatomical characteristics of interrenuncular septum (IRS) could be seen. Thirty sites in 30 kidneys (20 right, 10 left) from 27 patients were determined as showing IRS. They were seen less frequently in patients less than 7 years of age. The prevalence of IRS in the patients with vesico-ureteric reflux (VUR) was not significantly different from that in the patients without VUR. The interrenuncular septum was never seen on planar images and was most clearly demonstrated on conventional coronal tomographic images. The linear defects ascribed to IRS on 99Tcm-DMSA scintigrams were of a similar incidence to that reported previously. However, IRS is still an unestablished structure, and there is no evidence that these linear defects actually correspond to the structure described as the interrenuncular septum.

Child↗
PubMed1997

Visualization of lung cancer with 99Tcm-tetrofosmin imaging: a comparison with 201T1.

We evaluated the usefulness of 99Tcm-tetrofosmin imaging in lung cancer. The study sample comprised 46 patients with lung cancer. Single photon emission tomography was conducted after the intravenous injection of 740 MBq 99Tcm-tetrofosmin and 111 MBq 201T1-chloride. We obtained an uptake ratio (counts per pixel in the lesion/counts per pixel in contralateral normal lung) for each scan to evaluate the degree of uptake in the tumour. Our results demonstrate that 89.1% of the primary lung cancers were visualized by 99Tcm-tetrofosmin and 95.7% by 201T1. The difference between the 201T1 uptake ratio and the 99Tcm-tetrofosmin uptake ratio was significantly greater in squamous cell carcinomas than small cell carcinomas (P < 0.01) and tended to be greater in squamous cell carcinomas than adenocarcinomas (P = 0.093). This study has indicated that 99Tcm-tetrofosmin, like 201T1, is a highly effective agent in the delineation of lung cancer. The difference between the 99Tcm-tetrofosmin and 201T1 uptake ratios might provide further information regarding the histological type of lung cancer.

Adenocarcinoma↗
PubMed1997

[Evaluation of myocardial perfusion by 99mTc-tetrofosmin SPECT before and after emergent percutaneous transluminal coronary angioplasty for acute myocardial infarction].

To assess clinical performance of coronary perfusion in patients with acute myocardial infarction following successful PTCA, various 99mTc-tetrofosmin (TF) SPECT were obtained. Twenty-eight patients with acute myocardial infarction underwent TF SPECT before emergent PTCA (acute phase), after 7 days (subacute phase) and 4 weeks (chronic phase) later. Twenty-eight patients divided into 2 groups. Early group; time lug from onset of AMI till PTCA is 6 hours or shorter (n = 17), delayed group; time lug is more than 6 hrs (n = 11). The defect scores were graded by 4 points grading system (0 as normal to 3 as defect) in 14 myocardial segments. In early group, the mean defect score was 13 +/- 7 at acute phase, 6 +/- 5 at subacute phase, and 3 +/- 4 at chronic phase. In delayed group, the mean value of defect score at each phases were 18 +/- 7, 14 +/- 7, and 13 +/- 7. The improvement of defect score of early group was significantly larger than that of delayed group (p < 0.005). These data indicate that PTCA therapy for acute MI patients is useful particularly in the early stage following acute MI.

Aged↗
PubMed1997

[Can 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) evaluate the renal function without blood sampling?: consensus report from multicenter study].

A multicenter study was undertaken in Japan to evaluate the correlation between the percentage of renal uptake of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) estimated by the count-based gamma camera method and the blood clearance of 99mTc-MAG3. Twenty four centers were enrolled and 172 cases were finally analyzed in this study. The renal clearance of 99mTc-MAG3 (TER) was obtained by using a single blood sample taken at 44 min after injection. Comparison of TER and renal uptake provided a coefficient of correlation of 0.874; suggesting that sufficiently accurate quantification of renal function could be obtained from the renal uptake estimate by the gamma camera method. This study also showed that the comparison of renal function might be feasible among patients under the same protocols, although precise and careful consideration is required in each center.

Adolescent↗
PubMed1996

Early massive accumulation of In-111 pentetreotide in a metastatic liver tumor of islet cell carcinoma.

A 62-year-old woman was examined with In-111 pentetreotide and Ga-67 citrate. She had undergone an operation to resect a neuroendocrine tumor of the pancreas and still had masses in the liver. One of her hepatic lesions had been biopsied and acinar cell carcinoma was suspected. Fluid in the cyst of the tumor, however, contained a high concentration of gastrin and the tumor was strongly suspected of being a metastasis from the neuroendocrine tumor of the pancreas. The hepatic tumors quickly accumulated In-111 pentetreotide immediately after the injection, but there was no Ga-67 citrate uptake in the tumor. Five months after pentetreotide scintigraphy, her hepatic tumors were resected and histologically proven to be metastasis of islet cell carcinoma. In-111 pentetreotide provides information of the somatostatin-receptor status on the tumor and supports the diagnosis made by hormonal survey.

Biopsy↗
PubMed1996

Treatment of radioiodine-negative bone metastasis from papillary thyroid carcinoma with percutaneous ethanol injection therapy.

A 62-year-old woman with metastatic papillary thyroid carcinoma in the sternum was successfully treated with percutaneous ethanol injection therapy (PET) when previous radioiodine therapy and external irradiation were ineffective. The patient tolerated the treatment well and the refractory pain in the anterior chest wall that was alleviated with morphine prior to PEIT completely disappeared. No severe complications were observed. PEIT was performed 4 times (2 times with ultrasound guidance and 2 times with CT guidance). The posttreatment CT scan and 201Tl scintigraphy demonstrated significant decrease in the tumor volume. The serum thyroglobulin level fell to less than one-twentieth of the pretreatment value. It is suggested that PEIT has a value in treating bone metastasis from thyroid carcinoma which do not respond to radioiodine.

Bone Neoplasms↗
PubMed1996

The role of 201Tl scintigraphy in evaluating proliferative activity in thyroid neoplasms.

To identify the relationship between the uptake of 201Tl and the proliferative activity in thyroid neoplasms, 201Tl scintigraphy was performed in 57 patients with thyroid neoplasms. 201Tl uptake ratio was calculated in both the early and the delayed images and then compared with factors representing cellular or practical proliferative activity of the lesions. The labeling index (LI) for proliferating cell nuclear antigen (PCNA) was determined quantitatively by flow cytometry. There was a significant correlation between the uptake ratio and LI for PCNA. The correlation coefficient for the delayed ratio (DR) vs. LI was better than that for the early ratio (ER) vs. LI. As parameters for practical proliferation, the surgical stage in primary thyroid carcinoma or 131I uptake in recurrent thyroid carcinoma was focused on. DR was strongly related to these parameters, regardless of the histopathological features or size of the lesions. Our results suggest that 201Tl uptake in delayed thyroid scan is useful in assessing proliferative activity in thyroid neoplasms.

Adolescent↗
PubMed1996

Radionuclide venography as a clue to the diagnosis of Budd-Chiari syndrome.

A patient was examined with radionuclide venography (RVG) to investigate unilateral leg oedema which might be due to deep vein thrombosis. RVG with Tc-99m MAA demonstrated no findings to suggest deep vein thrombosis of the right leg. However, collateral flow derived from the left common iliac vein and truncated inferior vena cava (IVC) were revealed. Contrast venography confirmed the obstruction of IVC and collateral flow from the left common iliac vein to the left ascending lumbar vein. It also showed the obstruction of hepatic veins and the patient was finally diagnosed as Budd-Chiari syndrome. Although unilateral leg oedema is an atypical symptom in Budd-Chiari syndrome, the findings on RVG led us to conduct further imaging studies to reach the diagnosis.

Budd-Chiari Syndrome↗
PubMed1996

Percutaneous ethanol injection therapy for autonomously functioning thyroid nodule.

Four patients with solitary autonomously functioning thyroid nodule (AFTN; 2 toxic and 2 subclinically toxic) received ultrasonography (US)-guided percutaneous ethanol injection therapy (PEIT). The pretreatment scintigraphic appearance of the nodule was hot, and radioactivity in the extranodular tissue was completely suppressed throughout. Ninety-nine percent ethanol was slowly injected under US guidance. As a rule, the injection was performed in fractionated sessions and the treatment was repeated until the total amount of ethanol exceeded the baseline nodular volume. The therapy was successful. Complete remission of hyperthyroidism was observed among the patients with toxic nodule. The basal level of TSH and its response to TRH injection was normalized in the patients with subclinically toxic nodule. Posttreatment scintigrams revealed that the extranodular tissue recovered and radioactivity in the hot nodule had noticeably decreased. The rate of reduction in the nodular volume was more than 80% in all. There was no recurrence or development of hypothyroidism during a follow up of 10 to 23 months. The main side effect was mild and transient pain and/or a burning sensation at injection. No severe or permanent complications occurred. Although the number of our cases was small, the results suggest that PEIT is a useful program in treating AFTN.

Adult↗
PubMed1995

Anti-phospholipid antibodies and cerebral vasospasm following subarachnoid haemorrhage.

Delayed ischaemic deficits due to cerebral vasospasm contribute to the high morbidity and mortality rates associated with subarachnoid haemorrhage. We evaluated the usefulness of measuring anti-phospholipid antibodies (aPLs) for prediction of the occurrence of symptomatic vasospasm and the outcome after subarachnoid haemorrhage. 32 consecutive patients with subarachnoid haemorrhage due to ruptured cerebral aneurysms were studied. They were admitted and operated on within 72 hours after the onset of subarachnoid haemorrhage. aPLs such as lupus anticoagulants, anti-cardiolipin IgG and anti-cardiolipin IgM were measured repeatedly after admission. Furthermore, platelet count, platelet aggregability and plasma platelet factor 4 were also measured. Eleven among the 32 patients (34.4%) showed positive in the examination for aPLs. Although aPLs could not predict symptomatic vasospasm, once symptomatic vasospasm occurred, patients with aPLs frequently demonstrated cerebral infarction and therefore their outcome was worse. aPLs were associated with a severe initial clinical grade and SAH grade on CT scan. Therefore it may explain the association of aPLs with worse outcome. aPLs were detected between 1 and 7 days. Four of 6 patients (67%) with aPLs became negative between 7 and 13 days after subarachnoid haemorrhage. The mechanism of transient aPLs is unclear but it is more likely to occur in the severer grade patients. The reduction in platelet count, the increased platelet aggregability, and the increased plasma platelet factor 4 concentration were also observed in aPLs-positive patients with symptomatic vasospasm.

Adult↗
PubMed1995

Qualitative and quantitative evaluation of renal parenchymal damage by 99mTc-DMSA planar and SPECT scintigraphy.

The initial 99mTc-DMSA studies carried out over a four year period in 229 patients with various heterogenic causes of lower urinary tract abnormalities were reviewed. Anatomical damage to the renal parenchyma was graded by means of planar and SPECT studies into a six group classification proposed by Monsour et al.: grade 0 (normal), I (equivocal), II (single defect), III (more than 2 defects), IV (contracted or small) and V (no visualization). Parenchymal uptake of 99mTc-DMSA was quantitated from planar images at 2 hours postinjection by a computer assisted gamma camera method. SPECT studies could enhance the pick-up rate for parenchymal uptake defects by a factor of 1.5 in comparison with planar imaging. The incidence of anatomical damage to the renal parenchyma increased with a high radiological grade for VUR, and renal uptake per injection dose of 99mTc-DMSA by the individual kidney significantly decreased in grades III and IV of the anatomical classification. These data revealed that 99mTc-DMSA planar is still useful for evaluating gross structural damage and for quantitative evaluation of the kidney with computer assistance. SPECT scintigraphy is more effective in disclosing anatomical damage to the renal parenchyma than planar, although it needs further discussion as to whether SPECT may increase sensitivity with minimal or no adverse affect on specificity.

Adult↗
PubMed1995

The role of pre-operative thallium-technetium subtraction scintigraphy in the surgical management of patients with solitary parathyroid adenoma.

Since 1985 we have practised scan directed unilateral cervical exploration for patients with primary hyperparathyroidism (HPT) on the basis of a solitary parathyroid adenoma, and who had a pre-operative thallium-technetium subtraction scintigram demonstrating one focus of activity (positive scan). Between 1985 and 1993, a total of 160 patients with proven HPT and a technically satisfactory scintigram underwent neck exploration. Of these, 96 had positive preoperative scans, 81 (84.4%) of which accurately predicted the site of the tumour subsequently retrieved at operation. Seventy-four (77.6%) with positive scans, and 80 of the entire group, underwent unilateral cervical exploration with removal of a presumed single adenoma. Seventy-eight (97.5%) of these patients were cured of their HPT; two patients demonstrated mild persistent hypercalcaemia. Median operating time was significantly reduced for patients having unilateral as opposed to bilateral operation. Our results suggest that, when positive, thallium-technetium subtraction scintigraphy will accurately predict the site of a solitary parathyroid adenoma in a high proportion of patients and will thus permit a unilateral parathyroid exploration in these individuals. The usefulness of the technique is limited by its low sensitivity for small tumours.

Adenoma↗