J. Taki
Kanazawa University, Department of Nuclear Medicine, Faculty Member
Gated myocardial perfusion SPECT has been used to calculate ejection fraction (EF) and end-diastolic volume (EDV) and has correlated well with conventional methods. However, the comparative accuracy of and correlations across various... more
Gated myocardial perfusion SPECT has been used to calculate ejection fraction (EF) and end-diastolic volume (EDV) and has correlated well with conventional methods. However, the comparative accuracy of and correlations across various types of gated SPECT software are not well understood. Mathematic phantoms of cylindric-hemispheric hybrid models, ranging in volume from 34 to 266 mL, were generated. The clinical cases consisted of 30 patients who participated in a radionuclide angiography and gated blood-pool (GBP) study in addition to undergoing (99m)Tc-sestamibi gated SPECT. Four kinds of software, Quantitative Gated SPECT (QGS), the Emory Cardiac Toolbox (ECT), 4D-MSPECT, and Perfusion and Functional Analysis for Gated SPECT (pFAST) were used to compute EF and EDV, and the results were analyzed by multiple comparisons tests. Patients were classified into 4 groups (i.e., no defect, small defect, large defect, and small heart) so that factors affecting variation could be analyzed. I...
Research Interests: Mathematics, Nuclear medicine, Comparative Study, Medicine, Algorithm, and 15 moreNuclear, Humans, Female, Male, Perfusion, Accuracy, Clinical Sciences, Middle Aged, Observer Variation, Correlation coefficient, Coronary Circulation, Precision, Radiopharmaceuticals, Ejection Fraction, and Hybrid Model
Myocardial damage caused by vasospastic angina (VSA) may be detected by [123I]BMIPP, a beta-methyl-branched fatty acid. We investigated whether BMIPP could be used in the diagnosis and follow-up of patients with VSA. Thirty-two patients... more
Myocardial damage caused by vasospastic angina (VSA) may be detected by [123I]BMIPP, a beta-methyl-branched fatty acid. We investigated whether BMIPP could be used in the diagnosis and follow-up of patients with VSA. Thirty-two patients with VSA were studied with resting BMIPP-SPECT in comparison to stress perfusion imaging with either 201Tl or 99mTc-MIBI. During coronary arteriography, spasm was induced by provocative testing with acetylcholine or ergonovine, and only total or subtotal occlusion was considered positive. Decreased BMIPP uptake was semiquantitatively evaluated segmentally aided by polar map display. Reduced BMIPP uptake was observed in 25 of 32 patients (78%), with complete or partial agreement between the BMIPP abnormality and coronary territory seen in 23 patients (72%). In contrast, a perfusion abnormality was seen in only 10 patients (31%). In the repeat BMIPP study (n = 23) during the follow-up period (average 206 days), 11 of 14 patients who showed BMIPP improv...
Research Interests: Cardiology, Nuclear medicine, Medicine, Humans, Internal Medicine, and 15 moreFatty acids, Iodine, Female, Male, Heart, Follow-up studies, Acetylcholine, Perfusion, Clinical Sciences, Cardiac Catheterization, Middle Aged, Coronary Angiography, Single Photon Emission Computed Tomography, Time Factors, and Angina
Diagnosis of cardiac involvement is important for the management of patients with systemic sclerosis (SSc). This study was undertaken to determine the significance of gated myocardial perfusion SPECT in patients with SSc and whether... more
Diagnosis of cardiac involvement is important for the management of patients with systemic sclerosis (SSc). This study was undertaken to determine the significance of gated myocardial perfusion SPECT in patients with SSc and whether diastolic function measured by gated SPECT is an early sign of cardiac complications. Thirty-four patients with SSc and 16 control patients were studied using exercise nongated and resting gated myocardial perfusion SPECT. The SSc was classified by the modified Rodnan total skin score (TSS) into high-TSS (score > or = 10; n = 18) and low-TSS (score < 10; n = 16) groups. Gated SPECT was performed using 99mTc-methoxyisobutylisonitrile with 16 frames per cardiac cycle and quantitatively analyzed by QGS software and Fourier filtering of the volume curve. The parameters of ejection fraction (EF), peak filling rate (PFR), one-third mean filling rate, and time to PFR (TPFR) were calculated. A slight perfusion abnormality was observed in four and five pati...
Research Interests: Cardiology, Nuclear medicine, Medicine, Humans, Internal Medicine, and 15 moreSystemic sclerosis, Female, Male, Statistical Significance, Heart rate, Clinical Sciences, Middle Aged, Single Photon Emission Computed Tomography, Coronary Circulation, Radiopharmaceuticals, Ejection Fraction, Control Group, Heart Diseases, Diastole, and Diastolic dysfunction
Research Interests: Cardiology, Progressive Supranuclear Palsy, Multiple System Atrophy, Medicine, Humans, and 15 moreInternal Medicine, Female, Male, Heart, Differential Diagnosis, Clinical Sciences, Aged, Middle Aged, Myocardium, Neurodegenerative Disease, Coronary Circulation, Parotid Gland, Parkinson Disease, Control Group, and Diagnostic Criteria
To evaluate 123I labeled beta-methyl-branched fatty acid (BMIPP) myocardial uptake at rest in the segment with and without stress induced ischemia in patients with coronary artery disease, 123I-beta-methyl-branched fatty acid myocardial... more
To evaluate 123I labeled beta-methyl-branched fatty acid (BMIPP) myocardial uptake at rest in the segment with and without stress induced ischemia in patients with coronary artery disease, 123I-beta-methyl-branched fatty acid myocardial scintigraphy was performed at rest and was compared with the findings of stress-reinjection 201Tl myocardial scintigraphy in 31 patients with coronary artery disease. In 159 ischemic myocardial segments, equally decreased uptake on both reinjection 201Tl and fatty acid images was observed in 64 segments, more severely decreased uptake of fatty acid in 76 segments, and more severely decreased uptake of reinjection thallium in 19 segments. On the other hand, in 53 non-reversible defects, each patterns was observed in 41, 3, and 9 segments respectively. When comparing the ischemic segments with more reduced uptake of fatty acid than reinjection thallium (Group 1) and the ischemic segments with equally or less reduced fatty acid uptake than reinjection t...
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Research Interests: Cardiology, Humans, Fatty acids, Female, Male, and 13 moreAged, Middle Aged, Single Photon Emission Computed Tomography, Adult, Myocardium, Analysis of Variance, Sensitivity and Specificity, Hypertrophic Cardiomyopathy, Exercise Test, Exercise Tolerance, Myocardial Ischemia, Fatty acid metabolism, and Cardiovascular medicine and haematology
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ular dysfunction in patients with HCM is not well established. This study was performed to evaluate the sympathetic nerve activity in various cardiac regions and to investigate the rela- tionship between cardiac dysfunction and... more
ular dysfunction in patients with HCM is not well established. This study was performed to evaluate the sympathetic nerve activity in various cardiac regions and to investigate the rela- tionship between cardiac dysfunction and heterogeneity of the cardiac sympathetic nerve activity in patients with HCM. Meth- ods: Cardiac sympathetic nerve activity was evaluated in 25 patients with HCM and 10
Research Interests: Echocardiography, Humans, Left Ventricular Assist Device, Female, Male, and 13 moreRegression Analysis, Heart, Left Ventricular Dysfunction, Clinical Sciences, Middle Aged, Single Photon Emission Computed Tomography, Sympathetic Nervous System, Radiopharmaceuticals, Hypertrophic Cardiomyopathy, Stepwise Regression, Control Group, Case Control Studies, and Sympathetic nerve activity
Gated myocardial perfusion SPECT has been used to calculate ejection fraction (EF) and end-diastolic volume (EDV) and has correlated well with conventional methods. However, the com- parative accuracy of and correlations across various... more
Gated myocardial perfusion SPECT has been used to calculate ejection fraction (EF) and end-diastolic volume (EDV) and has correlated well with conventional methods. However, the com- parative accuracy of and correlations across various types of gated SPECT software are not well understood. Methods: Mathematic phantoms of cylindric- hemispheric hybrid models, ranging in volume from 34 to 266 mL, were generated.
Research Interests: Comparative Study, Nuclear, Software, Humans, Female, and 13 moreMale, Clinical Sciences, Middle Aged, Theoretical Models, Observer Variation, Single Photon Emission Computed Tomography, Retrospective Studies, Reproducibility of Results, Correlation coefficient, Coronary Circulation, Radiopharmaceuticals, Ejection Fraction, and Hybrid Model
Diagnosis of cardiac involvement is important for the management of patients with systemic sclerosis (SSc). This study was undertaken to determine the significance of gated myocardial perfusion SPECT in patients with SSc and whether... more
Diagnosis of cardiac involvement is important for the management of patients with systemic sclerosis (SSc). This study was undertaken to determine the significance of gated myocardial perfusion SPECT in patients with SSc and whether diastolic function measured by gated SPECT is an early sign of cardiac complications. Thirty-four patients with SSc and 16 control patients were studied using exercise nongated and resting gated myocardial perfusion SPECT. The SSc was classified by the modified Rodnan total skin score (TSS) into high-TSS (score > or = 10; n = 18) and low-TSS (score < 10; n = 16) groups. Gated SPECT was performed using 99mTc-methoxyisobutylisonitrile with 16 frames per cardiac cycle and quantitatively analyzed by QGS software and Fourier filtering of the volume curve. The parameters of ejection fraction (EF), peak filling rate (PFR), one-third mean filling rate, and time to PFR (TPFR) were calculated. A slight perfusion abnormality was observed in four and five pati...
Research Interests: Humans, Systemic sclerosis, Female, Male, Statistical Significance, and 11 moreHeart rate, Left Ventricular Dysfunction, Clinical Sciences, Middle Aged, Single Photon Emission Computed Tomography, Coronary Circulation, Radiopharmaceuticals, Ejection Fraction, Diastolic Dysfunction/CHF, Control Group, and Heart Diseases
rate forward CO measurement using the first-pass data with 99mTc-terofosmin, which is applicable to other "Tc-labeled myo cardial perfusion imaging agents.
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Preoperative assessment of residual hepatic functional reserve offers important strategic information for hepatic resection. To predict the postoperative residual liver function, we assessed the value of hepatic 99mTc-diethylenetriamine... more
Preoperative assessment of residual hepatic functional reserve offers important strategic information for hepatic resection. To predict the postoperative residual liver function, we assessed the value of hepatic 99mTc-diethylenetriamine pentaacetic acid-galactosyl-human serum albumin (99mTc-GSA) clearance estimated by dynamic SPECT analysis. We investigated 114 consecutive patients with liver disease, including 55 hepatectomy cases. One minute after injection of 185 MBq 99mTc-GSA, 15 serial dynamic SPECT images were obtained every minute. The initial five sets of SPECT images were analyzed by Patlak plot to estimate the sequential initial hepatic 99mTc-GSA clearance (mL/min) as an index of hepatic function. The sum of hepatic 99mTc-GSA clearance of the segments immune from resection was categorized as predicted residual 99mTC-GSA clearance. In the hepatectomy cases, scintigraphy was performed before and 37 +/- 10 d after the operation. Good correlation was observed between the total...
Research Interests: Magnetic Resonance Imaging, Treatment Outcome, Nuclear, Liver diseases, Humans, and 11 moreClinical Sciences, Single Photon Emission Computed Tomography, Time Factors, Prognosis, Radiopharmaceuticals, Liver Failure, X ray Computed Tomography, Organic Chemicals, Human Serum Albumin (HSA), Liver function tests, and Serum albumin
Dementia with Lewy bodies (DLB) needs to be distinguished from Alzheimer's disease (AD) because of important differences in patient management and outcome. Severe cardiac sympathetic degeneration occurs in DLB, but not in AD, offering... more
Dementia with Lewy bodies (DLB) needs to be distinguished from Alzheimer's disease (AD) because of important differences in patient management and outcome. Severe cardiac sympathetic degeneration occurs in DLB, but not in AD, offering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the diagnostic accuracy, in the ante-mortem differentiation of probable DLB from probable AD, of cardiac imaging with the ligand 123I-meta-iodobenzylguanidine (MIBG) which binds to the noradrenaline reuptake site, in the first multicenter study. We performed a multicenter study in which we used 123I-MIBG scans to assess 133 patients with clinical diagnoses of probable (n = 61) or possible (n = 26) DLB or probable AD (n = 46) established by a consensus panel. Three readers, unaware of the clinical diagnosis, classified the images as either normal or abnormal by visual inspection. The heart-to-mediastinum ratios of 123I-MIBG uptake were also calcul...
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Thallium-201 planar and SPECT studies were performed in 38 children with congenital heart disease using high-resolution three-headed SPECT. The 201Tl total or average right ventricular-to-left ventricular (RV/LV) count ratios were... more
Thallium-201 planar and SPECT studies were performed in 38 children with congenital heart disease using high-resolution three-headed SPECT. The 201Tl total or average right ventricular-to-left ventricular (RV/LV) count ratios were measured by summed short-axis images. In the planar study, the RV/LV systolic pressure ratio correlated with 201Tl RV/LV average count ratio (r = 0.91) better than that in the SPECT study (r = 0.78). However, in the SPECT study, patients with atrial septal defect (n = 9), ventricular septal defect (n = 13), tetralogy of Fallot and double outlet right ventricle (n = 6) showed a characteristic distribution in the plot of RV/LV pressure ratio versus 201Tl RV/LV total count ratio. A prospective study showed that the RV/LV average count ratio was a good predictor of RV/LV pressure ratio (n = 19, r = 0.91). Three-headed SPECT is useful for pediatric cardiac studies, and the overload types found in congenital heart disease seemed to be differentiated by the SPECT...
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High-resolution three-headed single photon emission computed tomography (SPET) equipped with fan-beam collimators was applied to myocardial perfusion imaging in infants aged from 1 to 11 months (n = 5). A tabletop designed specifically... more
High-resolution three-headed single photon emission computed tomography (SPET) equipped with fan-beam collimators was applied to myocardial perfusion imaging in infants aged from 1 to 11 months (n = 5). A tabletop designed specifically for infants was fixed on the SPET couch to reduce the radius of camera rotation to 13.2 cm. Significant improvement in resolution was achieved with the fan-beam collimators compared to parallel-hole high-resolution collimators. With the administration of approximately 37 MBq (26-44 MBq) 201Tl, 5 min acquisition time was possible for SPET imaging, which provided good image quality in all patients. Thus, a smaller administration dose is possible within a practical short acquisition time. High-resolution fan-beam SPET imaging can be a routine diagnostic method for heart disease in newborn babies and infants.
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Radiological diagnosis of deep soft tissue is often difficult. In the present study, thallium-201 ( Tl) uptake into haemangiomas and deep malignant soft tissue tumours was investigated in order to assess its clinical utility. Tl... more
Radiological diagnosis of deep soft tissue is often difficult. In the present study, thallium-201 ( Tl) uptake into haemangiomas and deep malignant soft tissue tumours was investigated in order to assess its clinical utility. Tl scintigraphy was reviewed in four patients presenting with soft tissue haemangiomas. Early and delayed planar images, obtained at 15 min and 3 h following the intravenous injection of Tl (111 MBq), were examined. The Tl uptake ratio was calculated by dividing the count density of the tumour region of interest (ROI) by that of the background ROI. Results were compared with those of five cases of rhabdomyosarcoma and a single instance of angiosarcoma. All haemangioma lesions demonstrated increased Tl uptake in early images. However, Tl uptake in delayed images was markedly decreased. No significant differences were observed in the early uptake ratio between haemangiomas (1.60-2.72) and reference malignant tumours (1.48-2.45); however, the difference was significant in delayed images (range, 1.01-1.26 vs. 1.43-2.03, respectively) ( P&lt;0.02). Deep soft tissue haemangiomas revealed Tl accumulation in early images; however, a rapid washout was observed in delayed images. This distinctive feature may facilitate the use of Tl scintigraphy in the diagnosis of haemangiomas.
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The aim of this study was to determine the feasibility of assessing left ventricular systolic ejection and diastolic filling by the edge detection method with ECG-gated single-photon emission tomography (G-SPET) data. Fifty-two patients... more
The aim of this study was to determine the feasibility of assessing left ventricular systolic ejection and diastolic filling by the edge detection method with ECG-gated single-photon emission tomography (G-SPET) data. Fifty-two patients who had undergone both G-SPET and gated equilibrium blood pool scintigraphy (GBP) within an interval of 2 weeks were enrolled. For G-SPET, 740 MBq of technetium-99m methoxyisobutylisonitrile
Research Interests: Cardiology, Nonparametric Statistics, Magnetic Resonance Imaging, Juvenile Idiopathic Arthritis, Risk assessment, and 53 moreAdolescent, Probability, Electrocardiography, Echocardiography, Prospective studies, Humans, Child, Hypertension, Edge Detection, Left Ventricular Assist Device, Blood Pressure, Female, Muscular Dystrophies, Feasibility Studies, Male, Education Systems, Statistical Significance, Heart rate, Infant, Acute Myocardial Infarction, Left Ventricular Dysfunction, Hyperuricemia, Mitral Valve Repair, Clinical Sciences, Aged, Middle Aged, Observer Variation, Blood Pressure Monitoring, Single Photon Emission Computed Tomography, Myocardial Infarction, Adult, Fourier transform, Public health systems and services research, Tissue Doppler Imaging, Cardiac Output Monitoring, Retrospective Studies, Angina pectoris, Prognosis, Correlation coefficient, Risk Assessment, Indexation, Ejection Fraction, Left Ventricular Function, X ray Computed Tomography, Autosomal Recessive, Diastolic Dysfunction/CHF, Reference Values, Healthy Subjects, Heart Ventricles, Blood Flow Velocity, Case Control Studies, The American, and Becker Muscular Dystrophy (BMD)
To clarify whether muscarinic acetylcholine receptor (mAChR) binding can be a viable muscarinic neuronal marker which provides therapeutic information different from perfusional information in global brain, we evaluated the discrepancy... more
To clarify whether muscarinic acetylcholine receptor (mAChR) binding can be a viable muscarinic neuronal marker which provides therapeutic information different from perfusional information in global brain, we evaluated the discrepancy between the distribution of cerebral blood flow (CBF), mAChR and its five subtypes of messenger ribonucleic acid (mRNA) in the acute (n=9) and chronic (n=8) phases of a middle cerebral artery (MCA) occlusion model and in sham-operated controls (n=6). In the acute phase, regional CBF was markedly reduced in the MCA territory, whereas mAChR was not reduced and the mRNA was reduced only slightly. In the chronic phase, mAChR was reduced markedly in the infarcted lesion and the mRNA was also reduced. The mAChR was slightly reduced in the ipsilateral substantia nigra and pontine nucleus because of remote effects; however, regional CBF in the substantia nigra was slightly increased and did not change in the pontine nucleus. The discrepancy between CBF and mAChR was clarified, and the tendency toward a reduction in mRNA in the acute ischaemic region without a reduction in mAChR suggested the presence of cholinergic neurons which were viable but hypometabolic. It is concluded that mAChR imaging may be of value for the assessment of the viable cholinergic neuron density in vivo.
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Histological diagnosis and grading of cartilaginous tumors are closely correlated with patient prognosis; consequently, they are essential elements. We attempted to clarify the characteristics of2O1T1 uptake in various histological types... more
Histological diagnosis and grading of cartilaginous tumors are closely correlated with patient prognosis; consequently, they are essential elements. We attempted to clarify the characteristics of2O1T1 uptake in various histological types of cartilaginous tumors and to assess its clinical value. Methods Twenty-two cases with histologically proven cartilaginous tumors (3 enchondromas, 15 conventional chondrosarcomas (grade I = 9, II = 5, III =
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Research Interests: Quantitative analysis, Humans, Standard Deviation, Left Ventricular Assist Device, Female, and 13 moreFunctional Imaging, Male, Heart, Organophosphorus Compounds, Clinical Sciences, Aged, Middle Aged, Single Photon Emission Computed Tomography, Quantitative Analysis, Diagnostic Accuracy, Myocardial Perfusion Imaging, Heart Ventricles, and Diagnostic Criteria
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Research Interests: Pain, Treatment Outcome, Risk assessment, Japan, Adolescent, and 23 moreCausality, Comorbidity, Thyroid Cancer, Humans, Female, Statistical Significance, Risk factors, Dose, Clinical Sciences, Aged, Middle Aged, Adult, Edema, Time Factors, Radiation Injuries, Retrospective Studies, Body Weight, Risk Factors, Risk Assessment, Side Effect, Radiopharmaceuticals, Salivary Gland, and Gastrointestinal Diseases
Several studies have shown the benefit of fluorine-18 fluorodeoxy glucose (FDG) imaging in the differentiation of solitary pulmonary nodules. The majority of malignant tumor have a higher glucose metabolic rate as compared to benign... more
Several studies have shown the benefit of fluorine-18 fluorodeoxy glucose (FDG) imaging in the differentiation of solitary pulmonary nodules. The majority of malignant tumor have a higher glucose metabolic rate as compared to benign lesions. However, there is a considerable variety in glucose metabolic rate that depends on the aggressiveness and histological subtype of the tumor. Technetium-99m sestamibi (MIBI) is
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123I-labelled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) was performed in 17 patients with hypertrophic cardiomyopathy, and was compared with 201Tl exercise... more
123I-labelled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) was performed in 17 patients with hypertrophic cardiomyopathy, and was compared with 201Tl exercise stress myocardial perfusion SPECT images. Fourteen patients showed asymmetrical hypertrophy, and three demonstrated apical hypertrophy. SPECT was performed 20 min and 3 h after injection of 111 MBq 123I-BMIPP at rest. Exercise stress 201Tl SPECT was performed at 10 min and 3 h after injection and was compared with BMIPP imaging. In 13 patients BMIPP accumulation in the hypertrophied area in the 20 min image was lower than that of 3 h 201Tl uptake. Interestingly, six patients demonstrated 201Tl redistribution in the region where the uncoupling of BMIPP uptake at 20 min and 201Tl accumulation at 3 h after exercise was observed. These findings suggest that impaired fatty acid metabolism or utilization in hypertrophic myocardium and ischaemia or impaired coronary flow reserve may be one of the causes of the abnormality of fatty acid accumulation.