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J Taki

Publications and source records attributed to J Taki.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Brain uptake ratio as an index of cerebral blood flow obtained with 99mTc-ECD].

A new index of cerebral blood flow (brain uptake ratio, BUR) using 99mTc-ECD was developed and evaluated in 66 patients (132 cerebral hemispheres). BUR was calculated from brain count in anterior planar image (60-80 sec after injection of 99mTc-ECD) divided by the summation of the count of aortic arch during first transit of radionuclide. BUR correlated well with brain perfusion index (BPI) obtained with Patlak plot method (r = 0.960, p < 0.001). In conclusion, BUR is useful as a simple and non-invasive index reflecting cerebral blood flow.

Adolescent↗
PubMed1997

[Evaluation of bone and soft tissue lesion using 99mTc-MIBI: comparison with 201Tl and the relation to chemotherapeutic effect].

Thirty-five patients with bone and soft tissue lesions were studied with 99mTc-MIBI and 201Tl to compare the uptake of two tracers. Planar images were obtained 15 min (early image) and 3 hr (delayed image) after the injection of both tracers. Images were evaluated visually and quantitatively using uptake ratio (lesion/background). In visual analysis, 23 of 35 patients showed similar uptake of both tracers, 9 showed more intense uptake of 99mTc-MIBI than 201Tl, and 3 showed more intense uptake of 201Tl than 99mTc-MIBI on early images. On delayed images, 21 of 32 patients showed similar uptake of both tracers, 3 showed more intense uptake of 99mTc-MIBI than 201Tl, and 8 showed more intense uptake of 201Tl than 99mTc-MIBI. In quantitative analysis, similar 201Tl and 99mTc-MIBI uptake ratios were obtained on early images. On delayed images, 99mTc-MIBI uptake ratios are less than that of 201Tl, but the difference was not significant. In some cases, 99mTc-MIBI accumulation was washed out on delayed images, therefore the early image is essential to evaluate 99mTc-MIBI accumulation. In all cases with the uptake ratios less than 1.20 on delayed 99mTc-MIBI images, chemotherapy was not effective. In malignant tumors, decreased uptake of 99mTc-MIBI accumulation on delayed images may indicate that chemotherapy is not effective. Delayed 99mTc-MIBI image may be a potential marker predicting chemotherapeutic effect in malignant bone and soft tissue tumors.

Adolescent↗
PubMed1997

Evaluating benign and malignant bone and soft-tissue lesions with technetium-99m-MIBI scintigraphy.

UNLABELLED: This study compares the ability of 201TI and 99mTc-MIBI to detect and assess tumor response to chemotherapy in malignant and benign bone and soft-tissue lesions. METHODS: Forty-two patients with various bone and soft-tissue pathologies (29 malignant and 13 benign lesions) were studied with 201TI and 99mTc-MIBI. Planar 201TI scintigraphy was performed 15 min after injection of 111 MBq of 201TI. Within 1 wk of the 201TI study, radionuclide angiography with 600-740 MBq of 99mTc-MIBI was performed and planar imaging was done 15 min later. RESULTS: In visual analysis, 31 of 42 patients showed similar uptake of both tracers, 8 showed more intense uptake of 99mTc-MIBI than 201TI and 3 showed more intense uptake of 201TI than 99mTc-MIBI. In quantitative analysis, similar 201TI and 99mTc-MIBI uptake ratios were obtained (1.96 +/- 1.25 versus 1.96 +/- 1.02, respectively; p = ns). The perfusion index derived from 99mTc-MIBI radionuclide angiography was higher than 99mTc-MIBI uptake ratio (2.33 +/- 1.23 versus 1.96 +/- 1.02, respectively; p < 0.005), but correlated well with 99mTc-MIBI uptake ratio (r = 0.75). In 11 patients with malignant tumors, 201TI and 99mTc-MIBI scintigraphy was repeated after chemotherapy and the uptake of both tracers was significantly suppressed in patients with complete response confirmed by histological evaluation. In patients with complete response (n = 3), the uptake ratio of both tracers was reduced by more than 50%, whereas, less than 20% reduction of uptake ratio was observed in patients with nonresponse (n = 6). CONCLUSION: The ability of 99mTc-MIBI to detect malignant and benign bone and soft-tissue lesions and to assess tumor response to chemotherapy was comparable to that of 201TI. In addition, blood flow could be assessed by radionuclide angiography with 99mTc-MIBI. Technetium-99m-MIBI is a promising radiopharmaceutical for the evaluation of bone and soft-tissue lesions.

Abscess↗
PubMed1997

Significance of late redistribution thallium-201 imaging after rest injection for detection of viable myocardium.

UNLABELLED: The aim of this study was to determine whether late redistribution imaging after rest injection of 201Tl would provide further information on myocardial viability over conventional rest-early redistribution 201Tl imaging. METHODS: Twenty-nine patients with coronary artery disease and left ventricular dysfunction underwent rest, early (3-4 hr) and late (20-24 hr) redistribution 201Tl and gated blood pool studies. In 14 patients with successful revascularization, gated blood pool study was repeated after the coronary intervention. RESULTS: Nine of 29 patients showed early redistribution, and six additional patients showed further redistribution on the late images. Of 136 segments with initial 201Tl defects, 18 showed early redistribution, and 10 showed late redistribution. When a threshold of 60% of peak activity was used as an index of myocardial viability, only a small fraction (3%) of the initial 201Tl defects were additionally considered viable by the late images. In 14 patients who underwent revascularization, the positive (69%) and negative (87%) predictive values of the early redistribution images for functional recovery were similar to those obtained by the late images (68% and 86%, respectively). CONCLUSION: Although late redistribution after rest injection of 201Tl occasionally occurs, most of the clinically relevant information on myocardial viability may be obtained by conventional rest-early redistribution 201Tl imaging when the defect severity is considered an index of tissue viability.

Aged↗
PubMed1997

Brain perfusion SPECT in Lyme neuroborreliosis.

SPECT imaging brain perfusion using 99mTc-HMPAO was performed on a 38-yr-old women with Lyme neuroborreliosis confirmed by autopsy. The patient had been suspected of spinocerebellar degeneration. Cerebral blood flow was diffusely decreased throughout cerebral cortices but cerebellar blood flow was not impaired, which indicated that the diagnosis was unlikely spinocerebellar degeneration. These findings suggested that brain perfusion SPECT provides useful information in diagnosing the patients with Lyme neuroborreliosis, especially when spinocerebellar degeneration is included in the differential diagnosis.

Adult↗
PubMed1997

[Evaluation of ischemic heart disease using the index of relative 99mTc-tetrofosmin uptake increase at exercise].

We calculated an increase of myocardial 99mTc-tetrofosmin uptake during exercise from resting condition, which was thought to reflect coronary flow reserve, and assessed whether this method enhanced the detection of coronary artery disease (CAD). Exercise myocardial SPECT was performed using 99mTc-tetrofosmin with one-day method (exercise-rest) in 26 patients. Twenty-one patients were suspected to have ischemic heart disease and 5 were control patients. A polar map was used to evaluate the increase in counts after exercise. The parameter of % uptake increase was obtained by the ratio of exercise and resting myocardial counts. The uptake was corrected for administration dose and time decay between the exercise and rest studies. The sensitivity for detecting patients with significant coronary stenosis by visual evaluation and % uptake increase map was 60% and 90%, respectively. In 5 patients, % uptake increase map detected stenosed coronary artery lesions that could not be detected by visual analysis. We concluded that the % uptake increase map combined with conventional SPECT images enhanced the detectability of coronary artery disease and the evaluation of the degree of coronary flow reserve.

Adult↗
PubMed1997

Assessment of improvement of myocardial fatty acid uptake and function after revascularization using iodine-123-BMIPP.

UNLABELLED: We used beta-methyl iodophenyl pentadecanoic acid (BMIPP) to evaluate changes in myocardial fatty acid utilization before and after revascularization and the ability of BMIPP to predict functional recovery in patients with chronic coronary artery disease. METHODS: Thirty-four patients with chronic coronary artery disease (60 +/- 10 yr) underwent BMIPP and 201Tl SPECT (stress-reinjection 201Tl in 29 patients and resting 201Tl in 5 patients) before and 2-5 wk after percutaneous transluminal angioplasty (n = 23) or coronary artery bypass surgery (n = 11). Cardiac function was evaluated by gated blood-pool scintigraphy (n = 26) or two-dimensional echocardiography (n = 8) before and after revascularization. RESULTS: In 32 patients with reduced BMIPP uptake before revascularization, scintigraphic findings with 201Tl improved in 28 patients after revascularization. In these 28 patients, BMIPP uptake improved in 20 patients (71%). Wall motion abnormality was observed in 16 of these 20 patients before revascularization, with 15 showing wall motion improvement after revascularization. In eight patients without improvement of BMIPP uptake, despite 201Tl uptake improvement, wall motion abnormality was observed in four patients before revascularization; after revascularization, one showed wall motion recovery, and three did not. Ejection fraction (EF) improvement after revascularization correlated best with the area of improved BMIPP uptake (r = 0.84, p < 0.0005). EF improvement also correlated with the area of improved reinjection 201Tl uptake (r = 0.54, p < 0.05) and improved 201Tl uptake at stress after revascularization (r = 0.48, p < 0.05). The area of discordant uptake of BMIPP less than reinjection 201Tl uptake before revascularization was a good predictor of EF improvement after revascularization (r = 0.58, p < 0.01); however, the area of reversible 201Tl defect was not (r = 0.34, p = 0.15). CONCLUSION: In patients with chronic coronary artery disease, functional improvement after revascularization is closely related to the recovery of BMIPP uptake. Discordant BMIPP uptake less than reinjection 201Tl uptake is a potential predictor of functional recovery.

Angioplasty, Balloon, Coronary↗
PubMed1996

Myocardial scintigraphic study with 123I 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid in patients with hypertrophic cardiomyopathy.

123I 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) myocardial scintigraphy and exercise stress thallium (TI)-201 myocardial scintigraphy were performed in 17 patients with hypertrophic cardiomyopathy (HCM) to evaluate the existence of abnormal fatty acid metabolism in the myocardium and the relationship between this abnormality and myocardial ischemia. On the BMIPP scintigraphy, abnormalities were found in 12 of 17 patients (71%). Five patients showing no abnormalities on the BMIPP scintigraphy had well preserved exercise tolerance and had longer exercise duration than the others showing BMIPP scintigraphic abnormalities (P < 0.001). On the evaluation of the segmental abnormalities, TI scintigraphic abnormalities were found in 15 (50%) of 30 segments showing decreased accumulation of BMIPP. On the other hand, BMIPP scintigraphic abnormalities were found in all segments showing decreased accumulation of TI. The sites of decreased accumulation of BMIPP and TI were in good agreement with the sites of wall hypertrophy. Four patients showing BMIPP scintigraphic abnormalities and no T1 scintigraphic abnormalities were in higher New York Heart Association functional classes, had shorter exercise duration (P < 0.05) than the 5 patients showing no abnormalities on either scintigraphy. It is concluded that abnormalities of fatty acid metabolism in the heart are detected at a high rate in patients with HCM, and may be due in part to factors other than myocardial perfusion disturbance.

Adult↗
PubMed1996

Comparison of defect size between thallium-201 and technetium-99m tetrofosmin myocardial single-photon emission computed tomography in patients with single-vessel coronary artery disease.

Defect size on exercise-rest technetium (Tc)-99m tetrofosmin myocardial perfusion imaging was compared with that on exercise-reinjection thallium-201 imaging with 20 patients with 1-vessel coronary artery disease. In each patient, exercise-reinjection thallium-201 single-photon emission computed tomography (SPECT) and exercise-rest Tc-99m tetrofosmin SPECT imaging were performed. For visual analysis of the obtained SPECT images, the left ventricular myocardium was divided into 20 segments based on 3 short-axis slices from the apical, middle, and basal ventricular levels. For quantitative analysis, a square region of interest was placed on the center of each segment which was used for visual analysis, and relative regional activity to the normal reference region was calculated for each segment. By visual interpretation of the images, exercise Tc-99m tetrofosmin imaging showed a smaller defect size than exercise thallium-201 imaging (6.9 +/- 3.9 vs 8.8 +/- 3.0 segments, p <0.01). In contrast, rest Tc-99m tetrofosmin imaging showed a defect size similar to that on reinjection thallium-201 imaging (5.9 +/- 3.6 vs 5.6 +/- 3.9 segments, p = NS). Similarly, the mean defect sizes during exercise determined by quantitative analysis were smaller on Tc-99m tetrofosmin SPECT than those on thallium-201 SPECT at all tested threshold cutoff points ranging from 50% to 70%, whereas there were no significant differences in defect sizes between rest Tc-99m tetrofosmin and reinjection thallium-201 imaging. These data indicate that exercise Tc-99m tetrofosmin SPECT defect size determined either by visual analysis or by quantitative analysis may be smaller than on exercise thallium-201 SPECT.

Aged↗
PubMed1996

Inguinoscrotal lymphatic reflux detected by lymphoscintigraphy.

We performed lymphoscintigraphy with 99mTc-human serum albumin in a case of suspected lymphedema of the right leg after inguinal lymph node dissection. Dermal backflow of the leg and lymphocele at the inguinal chain were observed, and lymphatic reflux into the scrotum was also delineated. The scintigraphy could demonstrate a persistent lymphatic problem under conservative treatment, and could lead the physician to conduct surgical treatment. Scintigraphic demonstration of the inguinoscrotal lymphatic reflux has not been previously reported.

Bone Neoplasms↗
PubMed1996

Metastatic calcification: accumulation of a bone tracer during dynamic data acquisition.

Metastatic calcification is often detected by bone scintigraphy. We recently saw metastatic calcification in the stomach and kidneys of a patient on continuous ambulatory peritoneal dialysis. Tc-99m HMDP accumulation into both organs was noted even in the first frame of dynamic data acquisition of 4 min/frame, suggesting that calcium deposits may create an aggressive process and we may obtain information on the calcium deposit rate to better understand the mechanism of metastatic calcification.

Aged↗
PubMed1996

Absent myocardial I-123 BMIPP uptake in a family.

A 72-year-old woman with hypertension showed no sign of myocardial accumulation of 123I-BMIPP, and 201Tl and 123I-MIBG scintigraphy demonstrated normal findings. Electrocardiography showed left axis deviation with inverted T waves in leads I, aVL, V2-6 and QT prolongation. Coronary arteriography, two dimensional echo cardiography and laboratory data showed no abnormality. Her 66-year-old sister with non-insulin-dependent diabetes mellitus also had no myocardial BMIPP uptake, but had normal 201Tl finding. ECG and chest film findings were normal. Laboratory data indicated slightly high fasted blood glucose, triglyceride and total cholesterol. Four sons of a 72-year-old woman also underwent BMIPP scintigraphy. No BMIPP uptake was also observed in her 2nd son (49 years old) and his electrocardiogram showed QT prolongation. Since these rare findings indicating no myocardial BMIPP uptake were seen in a family, we suspected that a hereditary myocardial metabolic abnormality accounted for them.

3-Iodobenzylguanidine↗
PubMed1996

Technetium-99m tetrofosmin uptake in lung cancer: comparison with thallium-201.

Technetium-99m tetrofosmin and thallium-201 lung SPECT imaging were performed in a patient with adenocarcinoma of the lung. Significant activities in the lung lesion were clearly depicted on both technetium-99m tetrofosmin and thallium-201 SPECT imaging. The early uptake, delayed uptake ratios and retention indices of the tumor were 2.75, 2.39 and -1.31 for thallium-201 imaging and 3.09, 2.27 and -26.5 for technetium-99m tetrofosmin imaging, respectively. This preliminary report suggests that technetium-99m tetrofosmin may have potential as a tumor imaging agent.

Adenocarcinoma↗
PubMed1996

Influence of associated viral hepatitis status on recurrence of hepatocellular carcinoma after hepatectomy.

The purpose of this study was to investigate the relation between the recurrence of hepatocellular carcinoma (HCC) and the histologic status of underlying chronic liver disease from a viewpoint of multicentric hepatocarcinogenesis. Sixty-eight patients who underwent curative resection of HCC and have been followed for more than 2 years are reported. Based on the microscopic findings of the noncancerous part of the liver, the patients were divided into normal liver (N,n = 2), chronic persistent hepatitis (CPH,n = 6), chronic aggressive hepatitis (CAH,n = 31), and liver cirrhosis (LC,n = 29) according to a classification by the European Association for the Study of the Liver. Background data for the groups showed no significant differences. Recurrence was observed in none of the patients in the N and CPH groups, 26 (83.9%) of the patients in the CAH group, and 12 (41.4%) of the patients in the LC group. The cumulative disease-free survival rate of the CAH group was significantly lower than that of the CPH group (p < 0.05) and LC group (p < 0.01). This study revealed that the histologic status of the underlying chronic liver disease influenced the recurrence rate in patients with HCC. CAH was considered to be a risk factor for recurrence after resection of HCC.

Aged↗
PubMed1996

Impaired fatty acid uptake in ischemic but viable myocardium identified by thallium-201 reinjection.

Iodine 123-labeled 15-iodophenyl-3-methyl-pentadecanoic acid (BMIPP) has been proposed as a potential myocardial fatty acid probe. We studied BMIPP uptake in ischemic myocardium identified by thallium reinjection. Fifty-five patients with coronary artery disease who had persistent defects on standard exercise-redistribution thallium imaging were investigated. Patients underwent exercise-redistribution-reinjection thallium and resting BMIPP imaging. BMIPP uptake less than that seen with thallium on reinjection imaging was observed in 105 (82%) of 128 myocardial segments with new fill-in after thallium reinjection and 87 (37%) of 238 segments with reversible thallium defects. In contrast, only 32 (19%) of 166 segments with no fill-in showed discordantly decreased BMIPP uptake. Quantitative analysis showed reduction in BMIPP activity compared with differential uptake of thallium, an index of resting myocardial perfusion, especially in the area of fill-in (53.5% +/- 15.0% vs 76% +/- 12.1% of peak; p<0.01). These observations are consistent with impaired fatty acid uptake in ischemic myocardium, particularly in the area of fill-in after thallium reinjection.

Adult↗
PubMed1996

Different immunosuppressive effects of liposomal FK506 in liver and kidney transplantation.

The efficacy of liposomal FK506 was compared between a canine liver transplantation model and a canine kidney transplantation model. The present study revealed that liposomal FK506 increased immunosuppressive efficacy of FK506 in liver transplantation but decreased in kidney transplantation. Because liposomal FK506 increased FK506 levels in the liver and spleen, and decreased FK506 levels in the kidney, it was suggested that enhanced immunosuppressive efficacy in liver transplantation should be attributed to the local immunosuppressive effects in the hepatic allograft rather than effective suppression of splenocyte activity.

Animals↗