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Sample records for 201tl myocardial single-photon

  1. Evaluation of dilated cardiomyopathy by 201Tl myocardial single photon emission computed tomography

    International Nuclear Information System (INIS)

    To estimate dilated cardiomyopathy (DCM)morphologically and quantitatively, 201Tl myocardial single photon emission computed tomography (SPECT) was performed in 14 DCM and 5 normal cases. Using a rotating dual-gamma camera system, resting SPECT data were collected for 6 minutes. Quantitative analysis of clinical cases was based on phantom studies. (I) Morphological features Marked spherical left ventricular (LV) dilatation (14/14), localized-diffuse low uptake or defect (12/14), and right ventricular visualization (6/14) were characteristic features in DCM. Differentiation of DCM from ischemic heart disease by SPECT was possible through the feature indicating disproportionately large LV cavity to defect size or degree. (II) Quantitative analysis When DCM was compared with normal control (n-5), following 3 features were impressive; 1) DCM was significantly higher in LV myocardial 201Tl uptake ratio and LV volume than normal control. (4.8+-1.3%: 3.3+-0.2%, p201Tl uptake ratio of unit volume (1 ml) than normal control. 3) DCM was significantly lower in mean myocardial count/mean lung count.ratio than normal control. Thus we concluded that 201Tl myocardial SPECT was useful non-invasive technique for diagnosis of DCM and was with fairly well correlation between morphology and quantitative estimations. Furthermore, this qutitative estimations. Furthermore, this quantitative method appears to be applicable for estimation of other cardiac disease. (author)

  2. Effects of smoking on myocardial injury in patients with conservatively treated acute myocardial infarction. A study with resting 123I-15-iodophenyl 3-methyl pentadecanoic acid/201Tl myocardial single photon emission computed tomography

    International Nuclear Information System (INIS)

    Many reports have demonstrated that smokers who have suffered an acute myocardial infarction (AMI) have a better prognosis than nonsmokers. The present study investigated the effects of current smoking on myocardial injury with resting 123I-15-iodophenyl 3-methyl pentadecanoic acid (BMIPP)/201Tl myocardial single photon emission computed tomography in 103 patients with conservatively treated AMI. The left ventricular myocardium was divided into 9 segments and BMIPP and 201Tl defects were scored using a 5-point grading system (0=normal and 4=no uptake). The sum of the defect scores was defined as the total defect score. There was no significant difference in either the baseline severity of the coronary artery discase or the total defect scores for BMIPP and 201Tl between the current smoker and nonsmoker groups. The difference between the total defect scores for BMIPP and 201Tl tended to be larger in the current smoker group than in the nonsmoker group (2.0±1.9 vs 1.3±1.6, p=0.056). Forty-one (53%) of 77 patients in the current smoker group exhibited a BMIPP/201Tl mismatch, whereas only 8 (31%) of 26 patients in the nonsmoker group did (p=0.047). In conclusion, current smokers had more likelihood of salvageable myocardium in areas at risk, as demonstrated by BMIPP/201Tl mismatch, in AMI than nonsmokers. (author)

  3. Relationship between the mismatch of 123I-BMIPP and 201Tl myocardial single-photon emission computed tomography and autonomic nervous system activity in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    The purpose of this study was to elucidate the relationship between the mismatch of thallium-201 (Tl) and iodine-123-beta-methyl-iodophenyl-pentadecanoic acid (BMIPP) myocardial single-photon emission computed tomography (SPECT) and autonomic nervous system activity in myocardial infarction (MI) patients. The subjects were 40 patients (34 males, 6 females) who underwent examinations by 123I-BMIPP and 201Tl myocardial SPECT imaging and 24-hour Holter monitoring within a 3-day period 3 weeks after the onset of their first MI. R-R intervals were analyzed every hour over a period of 24 hours by fast Fourier transformation (FFT). High frequency (HF) and low frequency (LF) were defined as markers of cardiac vagal activity in the former and the LF/HF ratio as sympathetic activity. Greater or more extensive decreases in the BMIPP image than that in the Tl image were defined as a positive mismatch. Patients were divided into positive and negative mismatch groups of 20 patients each. There were no significant differences between the 2 groups in age, sex, site of infarction, max CK (creatine kinase), max CK-MB, or left ventricular ejection fraction. The incidences of clinical signs suggesting residual myocardial ischemia were significantly greater in the positive than in the negative mismatch group (P123I-BMIPP and 201Tl myocardial SPECT 3 weeks after a first acute myocardial infarction with uncomplicated moderate or severe heart failure and decreased heart rate variability are related to residual myocardial ischemia. A combined assessment of heart rate variability in 24 hour Holter electrocardiogram (ECG) monitoring and perfusion-metabolism mismatch in 123I-BMIPP and 201Tl myocardial SPECT is useful for determining residual myocardial ischemia in the follow-up of those with acute myocardial infarction. (author)

  4. Quantification of infarct size by 201Tl single-photon emission computed tomography during acute myocardial infarction in humans. Comparison with enzymatic estimates

    International Nuclear Information System (INIS)

    We prospectively investigated whether 201Tl single-photon emission computed tomography (SPECT) could accurately diagnose the presence and quantify the extent of acute myocardial infarction when compared with infarct size assessed by plasma MB-creatine kinase activity. Thirty patients with enzymatic evidence of infarction were imaged within 12-36 hours of chest pain (mean, 23.4 hours). No patient had a previous infarction, and none underwent intervention seeking to restore coronary patency. Infarct size was quantified with computer-generated polar maps of the myocardial radioactivity and expressed as a percentage of the total left ventricular volume. To assess left and right ventricular performance, blood-pool gated radionuclide angiography was performed immediately after SPECT. All 30 patients had perfusion defects consistent with myocardial infarction. Scintigraphic and enzymatic estimates of infarct size correlated well for the group as a whole (r = 0.78, p less than 0.001, SEE = 9.1) but especially for those patients with anterior infarction (r = 0.91, p less than 0.001, SEE = 7.9). The poor correlation observed in patients with inferior infarction (r = 0.50, p less than 0.05, SEE = 10.0) was believed to be related to the frequent occurrence of right ventricular involvement because SPECT assessed only left ventricular damage, whereas the enzymatic method estimated the myocardial injury in both ventricles. A quantitative index of right ventricular infarctitative index of right ventricular infarct size, derived from the relation between the scintigraphic and enzymatic estimates, had a strong inverse correlation with right ventricular ejection fraction (r = -0.89, p less than 0.001, SEE = 3.6)

  5. Evaluation of left ventricular function in patients with myocardial infarction by noninvasive techniques using two-dimensional echocardiography and 201Tl single photon emission computed tomography

    International Nuclear Information System (INIS)

    Two dimensional echocardiography (2-DE) and 201Tl single photon emission computed tomography (SPECT) were performed in 51 patients with acute myocardial infarction (AMI), and the results were compared with those obtained by left ventriculography (LVG). After Loh et al.,the image of the left ventricular (LV) wall was divided into 9 segments. LV wall motion and Tl uptake in each segment were evaluated according to their severity and assigned scores from 1 to 5. The degree of global abnormality in each patient as determined by each method was obtained by the sum of the scores assigned to the 9 segments, and expressed as ?LVG, ?2-DE or ?SPECT, ?'LVG, ?'2-DE and ?'SPECT were also measured for 5 LV segments which were equivalent to the right anterior oblique view in LVG. Ejection fraction (EF) was measured by LVG using Kennedy's method. The mean value of ?2-DE was almost the same as that of ?LVG, but that of ?SPECT was significantly higher than that of ?LVG (p<0.05). The correlation coefficient of ?LVG with ?2-DE was 0.85 (p<0.001) and with ?SPECT, 0.72 (p<0.001). ?'LVG, ?'2-DE and ?'SPECT correlated significantly with EF (LVG: r=0.82; 2-DE: r=0.74; SPECT: r=0.63). Using multiple regession analysis, ?LVG and EF were estimated from the sum of the 2-DE and SPECT scores in each segment. In conclution, LV wall motion and ejection fraction can be estimated precisely by noninvasive diagnostic methods such as 2-DE and SPECT. (author)thor)

  6. Quantitative analysis of 201Tl-myocardial imaging, 2

    International Nuclear Information System (INIS)

    201Tl-myocardial imaging has been applied widely for the diagnosis of myocardial ischemia, but many problems have remained to be solved in analysing 201Tl uptake. Therefore, 201Tl (1.4 mCi) was administered twice serially, and 201Tl uptake into the myocardium was investigated quantitatively. The second uptake of 201Tl in the rest condition was estimated completely from the first uptake and the ratio of the first and second backgrounds which reflected levels of 201Tl in blood (r = 0.987, p 201Tl uptake into the myocardium was discussed in patients with pacemaker. By increasing heart rate from 60 tp 100 per minute, 201Tl uptake increased by 20 to 100% (the mean 36%) of estimated values, which was statistically significant (p 201Tl uptake according to an increase in heart rate was related to an increase in blood flow and changes in blood-tissue transport of 201Tl. (Tsunoda, M.)

  7. Evaluation of Agreement between 64-slice Computed Tomography Angiography and 201-Tl Single Photon Emission Computed Tomography-myocardial Perfusion Imaging in the Diagnosis of Significant Coronary Artery Disease

    International Nuclear Information System (INIS)

    To compare coronary computed tomography angiography (CTA) with single photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) for the detection of physiologically significant coronary artery disease (CAD). We evaluated 202 patients undergoing 64-slice coronary CTA and 201-Tl SPECT-MPI within a 3-month time interval. In addition, 68 patients underwent invasive coronary angiography (ICA). Coronary artery stenoses with luminal narrowing ? 50% were defined as 'significant' on CTA and ICA. All myocardial segments were classified as reversible or fixed perfusion defects and normal segments on 201-Tl SPECT-MPI, and were allocated to the corresponding coronary vessels. Agreement and diagnostic performance between each imaging modality for physiologically significant CAD was calculated using the kappa (?) statistic and receiver operating characteristic analysis, respectively. The sensitivity and specificity of CTA for the detection of physiologically significant CAD were 88% and 86% by patient-based analysis, and 84% and 91% by vessel-based analysis as compared to 201-Tl SPECT-MPI, respectively. The agreement between CTA and SPECTMPI was good (? = 0.647) and moderate (? = 0.558) by patientand vessel-based analyses, respectively. The accuracy of CTA for predicting perfusion defects on SPECT-MPI was comparable (area under the curve; 0.814 vs. 0.819, p=0.902 on patient-based analysis, and 0.808 vs. 0.749, p=0.197 on vessel-based analysis) to ICA. Coronaressel-based analysis) to ICA. Coronary stenosis ? 50% on coronary CTA shows good agreement with perfusion defects in SPECT-MPI.

  8. Evaluation of visualized left atrium by 201Tl myocardial scintigraphy

    International Nuclear Information System (INIS)

    201Tl myocardial scintigraphy was evaluated in patients with 18 mitral stenosis cases. Left atrium was to be seen in ANT (16.7 %), LAO (16.7 %), MLAO (16.7 %) and L-LAT (11.1 %), respectively. Furthermore, 201Tl uptake ratio of left atrium, right ventricle, pulmonary area tended significantly to increase in visible group compared with invisible group. PCW pressure was correlated with left atrial Tl uptake (r = 0.51, p 201Tl uptake. (author)

  9. 201Tl myocardial scintigraphy at rest and during exercise

    International Nuclear Information System (INIS)

    64 patients (38 after myocardial infarction, 23 with angina pectoris, 3 controls) were examined by different methods of 201Tl myocardial scintigraphy: scintigraphy during exercise and redistribution scintigraphy, seaprate scintigraphy at rest and during exercise, and scintigraphy at rest followed by scintigraphy during exercise, resp. The scintigraphy during exercise and redistribution scintigraphy proved to be most effective in ischemic and dicatricial myocardium. The scintigraphy during exercise should be performed rapidly since the redistribution begins immediately after ischemia

  10. The value of adenosine triphosphate stress 201Tl myocardial SPECT for detecting coronary artery disease

    International Nuclear Information System (INIS)

    Objective: To investigate the diagnostic value of adenosine triphosphate (ATP) 201Tl myocardial SPECT for coronary artery disease. Methods: 201Tl was injected after administration of adenosine triphosphate (0.14 mg·kg-1·min-1, 3 min). Myocardial SPECT imaging was performed at ten minutes and 3-4 hours after injection of 201Tl. Results: The sensitivity and specificity of ATP 201Tl imaging for detecting coronary artery disease was 88% and 90%, respectively. The side effects were mild and transient. Conclusion: ATP 201Tl imaging for detecting coronary artery disease is feasible

  11. Reverse 201Tl myocardial redistribution induced by coronary artery spasm

    International Nuclear Information System (INIS)

    Objective: To investigate the mechanism of reverse redistribution (RR) on dipyridamole 201Tl myocardial perfusion studies in the patients with coronary artery spasm. Methods: Twenty-six patients with coronary artery spasm and presented as RR on dipyridamole 201Tl myocardial perfusion studies were enlisted as RR group, while other 16 patients with no coronary artery stenosis nor RR were enlisted as control group. Dipyridamole test was repeated during coronary angiography. Corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) and TIMI myocardial perfusion grade (TMPG) were measured at RR related and non-RR related coronary arteries before and after dipyridamole infusion respectively. All of the data were analyzed by Student's t-test or ?2-test and correlation analysis. Results: Coronary artery angiography showed slower blood flow and lower myocardial perfusion in RR related vessels when compared with non-RR related vessels in RR group, but there was no significant difference among the main coronary arteries in control group. The perfusion defects of RR area at rest were positively related to slower blood velocity at corresponding coronary arteries (r = 0.79, t =10.18, P0.05). Conclusion: RR is related to the decreased blood flow and myocardial perfusion induced by coronary artery spasm at rest, which may be improved by stress test such as intravenous dipyridamole infusion. (authors)

  12. Clinical value of triple-energy window scatter correction in simultaneous dual-isotope single-photon emission tomography with 123I-BMIPP and 201Tl

    International Nuclear Information System (INIS)

    To improve the image quality in simultaneous dual-isotope single-photon emission tomography (SPET) with iodine-123 labelled 15-(p-iodophenyl)-3-methylpentadecanoic acid (BMIPP) and thallium-201, we applied the triple-energy window method (TEW) for correction of the cross-talk and scatter artifact. Seventy-one patients with coronary artery disease were included. 201Tl cross-talk into the 123I acquisition window (group 1, n 30) and 123I cross-talk into the 201Tl window (group 2, n = 41) were studied. In group 1, 123I images were first obtained (single-isotope images), followed by 201Tl injection and SPET acquisition using dual-isotope windows (dual-isotope images). In group 2, the order was reversed. The dual-isotope SPET images with and without TEW were compared with the single-isotope images. Qualitative evaluation was performed by scoring the segmental defect pattern. Detectability of the mismatched fatty acid metabolism on dual-isotope SPET was evaluated by receiver operating characteristic (ROC) curve analysis. Segmental defect pattern agreement between dual and corrected single images was significantly improved by TEW correction (P123I-BMIPP/201Tl SPET is feasible for the assessment of myocardial perfusion/metabolism mismatch. (orig.). With 10 figs., 4 tabs

  13. Scintigraphic detection of ischemic and other myocardial lesions using 201Tl

    International Nuclear Information System (INIS)

    Current knowledge of the myocardium scintiscanning using 201Tl is briefly outlined. The principle is shown of 201Tl cumulation in a healthy myocardium and the use of the radionuclide is justified. Heart scintiscanning after exercise or after administration of drugs increasing the blood flow through the coronaries allows detecting latent ischaemic heart disease. 201Tl scintigraphy can also be used for diagnosing the myocardial infarction, angina pectoris and other heart diseases. (J.P.)

  14. Effects of smoking on lung uptake of 201Tl during exercise myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Objective: To investigate the influence of smoking on lung uptake of 201Tl during myocardial perfusion imaging. Methods: Ninety-two healthy subjects, with normal 201Tl myocardial perfusion imaging findings but no evidence of left ventricular hypertrophy and pulmonary disease, were divided into three groups, smoker, nonsmoker and quitted smoker groups. Exercise/delay 201Tl myocardial perfusion imaging was performed on all subjects included. Lung/heart ratio was defined on the anterior planar image obtained during exercise tomography. Results: Both the lung/heart ratios during exercise in smoker (0.40 ± 0.07, F=10.635, P201Tl lung/heart ratios in smokers are higher than in nonsmokers and this must be kept in mind when 201Tl lung/heart ratios are used clinically, even in quitted smokers

  15. 201Tl in myocardial diagnosis: studies on the influence of dipyridamole, dobutamine ergometer exercise and background subtraction on the 201Tl myocadial scintiscam

    International Nuclear Information System (INIS)

    Changes in 201Tl myocardial scintiscans upon administration of dipyridamole or dobutamine and upon ergometer exercise relative to scintiscans at rest were investigated as well as the influence of myocardial background subtraction on scintiscan quality and information. A total of 90 201Tl examinations were carried out in 59 patients. 18 patients had no myocardial disease, 30 patients had a coronary disease, 5 patients suffered from cardiomyopathy and 6 from left ventricular hypertrophy. The findings are discussed in detail. (orig.)

  16. Correlation of myocardial uptake of 201Tl with local perfusion in the dog heart

    International Nuclear Information System (INIS)

    34 anesthetized and thoracotomized dogs are studied. The local myocardial blood flow is measured with sup(99m)Tc human albumin microsphere. The intramyocardial distribution of 201Tl in relation to local blood flow is studied in basal conditions (24 dogs), after experimental infarction (4 dogs) and postischemic reactive hyperhemia (6 dogs). We conclude that during basal conditions, after infarction and hyperhemia the 201Tl myocardial distribution reflect with damping the variations of blood flow

  17. Comparative study of 201Tl-scintigraphic image and myocardial pathologic findings in patients with dilated cardiomyopathy

    International Nuclear Information System (INIS)

    The objective of the present study was to characterize the production of 201Tl myocardial perfusion defects, the relation between the 201Tl multiple small defects and the myocardial damage indicated by myocardial fibrosis shown histopathologically in patients with dilated cardiomyopathy (DCM). Rest 201Tl scintigraphy was performed in thirty-seven patients. 201Tl myocardial SPECT images were visually classified into 4 grades according to the severity of inhomogeneous perfusion defects (IPD), 0: none, 1: slight, 2: moderate, 3: severe. 201Tl uptake, defect regions (DR), and coefficient of variation % (CV%) were also quantified by Bull's eye quantification in nineteen patients. 201Tl perfusion defects were observed in 35 (94.6%) patients, of whom 29 (78.4%) showed inhomogeneous perfusion defects. Twenty-four (64.9%) showed Stage 0 and 1 201Tl findings, and 21 (62.2%) had myocardial fibrosis in stage 1. Clinically, the correlation between the grades of the IPD, % 201Tl uptake, DR and CV% of myocardial uptake, which were calculated semiquantitatively by Bull's eye image, and the histological grades of fibrosis were also good (IPD vs. fibrosis: r=0.7014; % 201Tl uptake vs. fibrosis: r=-0.6542; DR vs. fibrosis: r=0.7027; CV% vs. fibrosis: r=0.6985). The 201Tl SPECT findings were in close agreement with the severity of myocardial fibrosis confirmed by autopsy, but theial fibrosis confirmed by autopsy, but the grading of the IPD was not related to the ejection fraction or left ventricular diameter. It showed a higher rate of inhomogeneous 201Tl myocardial perfusion defects (78.4%) in patients with DCM. This result may contribute to the clinical evaluation of DCM or differentiation from other diseases. Furthermore, the grading of 201Tl inhomogeneous perfusion defects related to the myocardial fibrosis of left ventricular myocardium may contribute to speculation of the myocardial degenerative stage in clinical settings. (author)

  18. Dipyridamole 201Tl myocardial SPECT imaging in patients with dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Objective: To explore the characteristics of dipyridamole 201Tl myocardial perfusion imaging (MPI) SPECT in patients with dilated cardiomyopathy. Methods: Thirty patients with dilated cardiomyopathy underwent pharmacological stress 201Tl MPI SPECT after intravenous infusion of dipyridamole (0.56 mg/kg) for 4 min. The early and delayed SPECT images were acquired respectively at 10 and 240 min after 201Tl injection. The images were analyzed and reported by two or three experienced nuclear medicine physicians. Results: All patients were found to have abnormal perfusion patterns at delay imaging, however 90.00% (27/30) were also abnormal at early images. Six patients had reverse redistribution. Conclusion: Dipyridamole 201Tl MPI SPECT imaging may be of some value for the assessment of patients with dilated cardiomyopathy. (authors)

  19. Diagnostic use of T2-weighted inversion-recovery magnetic resonance imaging in acute coronary syndromes compared with 99mTc-pyrophosphate, 123I-BMIPP and 201TlCl single photon emission computed tomography

    International Nuclear Information System (INIS)

    The incidence of missed diagnoses of acute cardiac ischemia in the emergency department could be reduced by a new imaging modality. In the present study, the clinical significance of 99mTc-pyrophosphate (PYP), 123I-?-methyl-p-iodophenyl-pentadecanoic acid (BMIPP), 201TlCl scintigraphy (imaging) and T2-weighted inversion-recovery magnetic resonance imaging (MRI) for the detection of culprit lesion in patients with acute coronary syndromes (ACS) was compared. The study group comprised 18 patients with ACS: 12 patients with acute myocardial infarction (AMI) (11 males; mean age, 63±11 years) and 6 patients with unstable angina (UA) (3 males, mean age, 67±5 years). Of the 12 patients with AMI, 10 underwent 201TlCl and PYP single photon emission computed tomography (SPECT) studies as a dual-energy acquisition (201TlCl/PYP) and 8 underwent 201TlCl SPECT within 1 week of the BMIPP study. All 18 patients underwent BMIPP SPECT and MRI. The MRI pulse sequence was black blood turbo short-inversion-time inversion recovery (STIR) (breath-hold T2-weighted studies). The T2-weighted inversion-recovery MRI showed higher sensitivity and negative predictive value than PYP and 201TlCl, and higher specificity and positive predictive value than BMIPP and 201TlCl. The area under the receiver-operating characteristic curve for PYP, BMIPP, 201TlCl and MRI was 0.787, 0.725, 0.731 and 0.878, res was 0.787, 0.725, 0.731 and 0.878, respectively. The difference between the areas of MRI and BMIPP was significant (p<0.05). Accurate detection of culprit lesion is improved by using MRI rather than BMIPP, particularly for patients with ACS. (author)

  20. Sequential change of cardiomyopathy of Duchenne muscular dystrophy by 201Tl myocardial SPECT

    International Nuclear Information System (INIS)

    201Tl myocardial SPECT were performed to evaluate of cardiomyopathy in Duchenne type of progressive muscular dystrophy (DMD). Follow up SPECT images of the same patients were also obtained about 1 year after the first scan. Cases subjected to study were 10 DMD. At the first study the hypoperfusion area of the left ventricular muscle were observed in 6 cases (60%) out of 10. At the second study the hypoperfusion areas became wider and lower in 4 out of 6 cases (66.7%). The new hypoperfusion area which was not demonstrated at the first study was observed at the second study in one case of these cases. These results suggested that the positive rate of cardiomyopathy in DMD by 201Tl myocardial SPECT was high, and 201Tl myocardial SPECT is a useful examination to detect the change of myocardial damage in DMD. (author)

  1. Detecting viable hibernating myocardium in chronic coronary artery disease. A comparison of resting 201Tl single photon emission computed tomography (SPECT), 99mTc-methoxy-isobutyl isonitrile SPECT after nitrate administration, and 201Tl SPECT after 201Tl-glucose-insulin infusion

    International Nuclear Information System (INIS)

    To identify and quantify the amount of viable hibernating myocardium in patients with chronic coronary artery disease, resting 201Tl single photon emission computed tomography (SPECT) was compared with 99mTc-methoxy-isobutyl isonitrile (MIBI) SPECT after nitrate infusion (nitrate-99mTc-MIBI) and 201Tl SPECT after 201Tl with glucose-insulin-potassium infusion (201Tl-GIK) in 25 patients. Twenty-one patients also underwent completely left ventriculography beforehand and 5±4 months afterwards. SPECT images were divided into 9 segments and scored visually from 0 (normal uptake) to 3 (absent). The defect score was calculated as the summation of the total scores (TDS) in each patient. The TDS of nitrate-99mTc-MIBI images (6.3±4.3) and 201Tl-GIK images (5.8±4.2) were significantly lower than the 7.4±4.3 of resting 201Tl images (p201Tl-GIK imaging (85%) was significantly higher (p99mTc-MIBI imaging (79%) also tended to be higher (p=0.08), than that of 201Tl imaging (62%) in detecting viable myocardium. The specificity of the 3 methods was almost the same. The nitrate-99mTc-MIBI and 201Tl-GIK methods were more useful than the resting 201Tl method for evaluating viable hibernating myocaor evaluating viable hibernating myocardium. Furthermore, the 201Tl-GIK method may provide a more accurate estimate of the amount of viable myocardium than the nitrate-99mTc-MIBI method. (author)

  2. Two dimensional polar coordinate representation (bulls-eye view) method of the 201Tl myocardial SPECT

    International Nuclear Information System (INIS)

    Two dimensional polar coordinate representation (bulls-eye view) method was applied to the 201Tl myocardial imaging by single photon emission CT (SPECT) and this method was compared with a conventional SPECT image for the ability to detect the abnormalities. We examined 5 normals and 15 patients (10 angina pectolis and 5 myocardial infarction), whose diagnosis were confirmed by coronary angiography. Diagnostic efficacy of two methods was evaluated in two groupes of radiologists by means of ROC (receiver operating characteristic) curve. Radiologists in A group have three years experience or more in nuclear medicine and those in B group have less than one year experience. As a result, diagnostic accuracy of conventional method was 93 % in a group and 55 % in B group. The accuracy by the two polar coordinate representation was increased from 55 % to 86 % in B group, although no remarkable improvement was seen in the accuracy (90 %) of A group. The consuming time for diagnosis was shortend by using the two dimensional polar coordinate representation method, especially in B group. This result suggests that the two dimensional polar coordinate representation method is useful for reading the myocardial imaging in not-well trained radiologists as well as in the well trained. (author)

  3. Prognostic value of gated 201Tl myocardial perfusion SPECT imaging in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Objective: To study the prognostic value of gated 201Tl myocardial perfusion SPECT imaging in patients with coronary artery disease and assessment of therapy strategy for the individual patient. Methods: Eighty-four patients underwent rest and exercise stress 201Tl gated myocardial perfusion SPECT imaging and were followed up for (32.92 ± 16.77) months. Images were studied using 17 segments and 1 to 4 scoring. Global summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS=SSS-SRS) were also calculated. Post-stress and rest ejection fraction (EF) were automatically measured. Results: Nine cardiac events occurred (3.90% per year). SSS, SDS, SRS and EF were the independent predictors of cardiac events (P201Tl myocardial perfusion SPECT imaging can provide prognostic assessment for the patients with coronary artery disease and guide in selection of therapeutic strategy. Among all of the indices SSS is the best predictors of cardiac events. (authors)

  4. Impact of diabetes mellitus on worsening of the left ventricular ejection fraction in exercise-gated 201Tl myocardial single photon emission computed tomography in patients with coronary artery disease

    International Nuclear Information System (INIS)

    It remains uncertain whether factors other than the severity of coronary artery disease (CAD) are associated with the worsening of the left ventricular ejection fraction (LVEF) by exercise. In the present study the impact of coronary risk factors on the worsening of LVEF by exercise was investigated in 391 patients with known or suspected CAD using exercise-gated 201Tl scanning to calculate the LVEF. Significant worsening of the LVEF by exercise was defined as >4.7% (mean plus 1 SD of the value in 116 patients without CAD). Multivariate analysis revealed that diabetes mellitus (DM) was an independent risk factor for the worsening of LVEF by exercise in patients with multivessel (2- or 3-vessel) CAD with an odds ratio (95% confidence interval) of 2.2 (1.1-4.5, p=0.037). In 157 patients with 2- or 3-vessel CAD, 20 (23.5%) of 85 nondiabetic patients and 31 (43.1%, p=0.009 vs nondiabetic patients) of 72 diabetic patients showed significant worsening of LVEF by exercise. In patients with 2- or 3-vessel CAD, there was no significant difference in Gensini score or reversibility of perfusion defects between nondiabetic and diabetic patients. Thus, DM is a risk factor for worsening LVEF by exercise in addition to the severity of CAD. (author)

  5. Quantitative analysis of right ventricular overloading by 201Tl myocardial SPECT

    International Nuclear Information System (INIS)

    Clinical usefulness of quantitative analysis of right ventricular overloading was evaluated by 201Tl myocardial SPECT in comparison with cardiac catheterization and MRI. Seventy-four MBq of 201TlCl was intravenously injected and 201Tl myocardial SPECT was performed on 40 patients (mean age: 61.0±11.8) with right ventricular overloading. Regions of interest (ROI) were selected on right and left ventricular walls in a midventricular short axis image of SPECT and uptake of each ROI were counted. The right ventricle (RV)/left ventricle (LV) 201Tl uptake ratio (R/L-Tl) was calculated. Wall thickness of RV and LV were measured on MRI and the RV/LV wall thickness ratio (R/L-WT) was calculated. RV and LV pressure were recorded in cardiac catheterization, and the RV/LV systolic pressure ratio (R/L-P) was calculated. There was significant positive correlation (Y=0.73X+0.19, r=0.71, p201Tl myocardial SPECT is useful to estimate RV/LV wall thickness ratio and pressure ratio. (author)o and pressure ratio. (author)

  6. Quantitative analysis of 123I-BMIPP imaging in relation to exercise-redistribution 201Tl in patients with old myocardial infarction

    International Nuclear Information System (INIS)

    Myocardial kinetics of 123I-labeled 15-(p-iodophenyl) 3R, S-methylpentadecanoic acid (BMIPP) was evaluated with BMIPP imaging in conjunction with stress-201Tl. We studied 20 patients with old myocardial infarction. BMIPP SPECT was obtained at 20 min and 3 h after injection. On a separate day, exercise stress-201Tl SPECT was performed at 10 min and 3 h after injection. Then, left ventricular myocardium was divided into 20 segments. For quantitative analysis, in each SPECT data, the maximum value (average counts per pixel) of all 20 myocardial segments was taken as 100%; the other values were calculated as a percentage of this maximum (Relative regional uptake, RRU). On the basis of stress-201Tl pattern, the myocardial segments were classified into 4 groups; normal 201Tl uptake, reversible 201Tl defect, fixed 201Tl defect and 201Tl defect with reverse redistribution. The 20 min BMIPP showed reduced activity compared with 3 h-201Tl (p201Tl redistribution (50/111 segments, 45%), implicating impaired fatty acid utilization at resting condition. The washout rate of the segments with reversible 201Tl defect (-1.6±13.9%) was significantly lower than that of the segments with normal 201Tl uptake (9.0±9.8%) and fixed 201Tl defect (3.8±12.9). Thus, BMIPP in combination with stress 201Tl imanation with stress 201Tl imaging provides precise information on impaired myocardial fatty acid utilization in patients with old myocardial infarction. (author)

  7. Diagnosis of myocardial ischaemia using exercise ST mapping and afterload 201Tl scintigraphy

    International Nuclear Information System (INIS)

    Two non-invasive methods are compared used in the diagnosis of myocardial ischaemia, i.e. precordial exercise mapping of the ST segment and after load 201Tl scintigraphy of the myocardium.High sensitivity of mapping (89.3%) and of 201Tl scan (92.9%) was found compared to the findings on the coronary arteries. The specificity of both methods was lower (57.1%). Both methods give similar results in diagnosis of myocardial ischaemia; for localization the affection site thallium scintigraphy of the myocardium is preferably used. (author). 2 figs., 2 tabs., 23 refs

  8. Cold pressor 201Tl myocardial scintigraphy in the diagnosis of coronary artery disease

    International Nuclear Information System (INIS)

    201Tl myocardial scintigraphy was performed during cold pressor stimulation in 36 patients aged 36 to 69 years. Thirty-one patients had coronary artery disease and 5 patients did not, as confirmed by coronary cineangiography. 201Tl (1.5 to 2 mCi) was injected at 30 seconds of the cold pressor stimulation. The product of systolic pressure X heart rate increased from a baseline of 77.4 +/- 16 (standard deviation [SD]) to 103.6 +/- 17 at 30 seconds of the cold pressor test (p less than 0.0005). Transient perfusion deficits developed in 24 of 31 patients with coronary artery disease (sensitivity 77%), and all 5 patients without coronary artery disease had normal scintigrams. The sensitivity in detecting coronary artery disease was 40% in patients with 1 vessel disease, 91% in patients with 2 vessel disease, and 100% in patients with 3 vessel disease. Exercise electrocardiograms (available in 29 of 36 patients) were positive for ischemia in 18 of 24 patients with coronary artery disease and in 1 of 5 patients without coronary artery disease (sensitivity 75% and specificity less than 80%). Exercise 201Tl scintigrams, obtained in 16 patients, were positive in 11 patients with coronary artery disease and positive cold pressor 201Tl scintigrams. Five patients without coronary artery disease and with normal cold pressor 201Tl scintigrams had normal exercise 201Tl scintigrams. Coronary cineangiography performed duams. Coronary cineangiography performed during cold pressor stimulation in 6 patients who had positive cold pressor and exercise 201Tl scintigrams did not show coronary spasm. Our data indicate that cold pressor thallium-201 scintigraphy offers promise as a noninvasive test in the diagnosis of coronary artery disease and may be used in patients in whom exercise testing is not feasible

  9. [Usefulness of 201Tl/123I-BMIPP myocardial SPECT to evaluate myocardial viability and area at risk in acute myocardial infarction--comparison with 201Tl/99mTc-PYP dual SPECT].

    Science.gov (United States)

    Isobe, N; Toyama, T; Hoshizaki, H; Oshima, S; Taniguchi, K

    1997-04-01

    To evaluate the area at risk and the myocardial viability of acute myocardial infarction (AMI), we compared rest 123I-beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP) and 201Tl myocardial SPECT with 201Tl/99mTc-PYP dual SPECT (D-SPECT) in 65 patients (mean age 64 +/- 11 years) with AMI. D-SPECT was performed in 3 to 5 days, 123I-BMIPP myocardial SPECT in 5 to 7 days, and left ventriculography on 1 month after onset of AMI. Furthermore, 201Tl/123I-BMIPP myocardial SPECT and left ventriculography were performed on 4 months after onset of AMI. The area which showed the reduced 123I-BMIPP uptake was larger than that showed the accumulation of 99mTc-PYP. The improvement of regional wall motion on 4 months after onset of AMI tended to be more closely correlated with the existence of discrepancy zone between 201Tl and 123I-BMIPP uptake than that of overlap zone between 201Tl and 99mTc-PYP uptake in acute period. We conclude that 201Tl/123I-BMIPP myocardial SPECT is more useful to evaluate the area at risk and myocardial viability of AMI than D-SPECT. PMID:9183144

  10. Scintigraphy of the heart with the aid of 201Tl in diagnosis of acute myocardial infarction

    International Nuclear Information System (INIS)

    In patients with acute myocardial infarction of different localization by the method of heart scitigraphy using 201Tl irradiation doses, extraction factors in myocardium, 201Tl distribution in the heart are considered. A good correlation between ECG data and scintigraphy as to myocardium localization is pointed out. Advantages (availability, acceptable radiation doses, high sensitivity for the first 12-24 hours after the appearence of first symptoms etc.) and disadvantages (impossibility of the differentiating of acute, developing or ''chronic'' infarction) of the method are shown

  11. Potentialities of using 201Tl-chloride in the differential diagnosis of coronarogenic and extraconarogenic myocardial lesions in menopausal females

    International Nuclear Information System (INIS)

    76 menopausal females were subjected to general clinical examination: biochemical investigation of carbohydrate, protein and lipid metabolism; radioimmunoassay of hormones; myocardial scintigraphy with 201Tl-chloride to diagnose coronarogenic and extracoronarogenic myocardial lesions. It is shown that the application of myocardial scintigraphy with 201Tl-chloride in menopausal females has followed to clarify the degree of distrophic changes in the myocardium of the left ventricle and to differentiate dyshormonal dystrophy and myocardial ischemia

  12. Quantitative assessment of myocardial blood flow by measurement of fractional myocardial uptake of 201Tl

    International Nuclear Information System (INIS)

    Fractional Myocardial uptake of 201Tl was measured for the quantitative assessment of myocardial blood flow in coronary artery disease (CAD). 10 normals and 28 CAD, 7 of which have less than 50% stenosis (CAD I) and 21 of which have more than 50% stenosis (CAD II) in the proximal portion of coronary arteries, were studied at rest and with submaximal exercise loading by bicycle ergometer. After intravenous injection of 201Tl, its rapid transport process was recorded during the initial 5 minutes by a scintillation camera and a minicomputer. Total injected dosage (T) was obtained from the counts of the entire chest region during the initial passage of the tracer through the heart and lung. Myocardial uptake (M) was counted with the same geometry from the subsequent accumulation within the myocardial region with subtraction of the background activities in the upper mediastinal region (B). The fractional myocardial uptake of 201Tl ((M-B)/T) is assumed to be proportional to the fractional myocardial blood flow to cardiac output (MBF/CO) according to the indicator fractionation principle. The average value of MBF/CO at rest in CAD (4.11 +- 1.12%) was significantly greater than in normals (3.36 +- 0.49%), which may be caused by an increased left ventricular mass in CAD. Change rate of MBF/CO on the exercise loading was significantly less in CAD I (1.36 +- 0.14) and in CAD II (1.11 +- 0.21) than in normals (1.75 +- 0.11). MBF/CO increased propoals (1.75 +- 0.11). MBF/CO increased proportionally to the increment of the double product of heart rate and systolic blood pressure by exercise loading in normals, whereas it didn't in CAD. The sensitivity of this method was superior to the stress electrocardiogram and the stress myocardial perfusion imaging, not only in CAD II but also in CAD I. This result indicated that this type of global assessment of the myocardial reserve capacity is valuable in addition to the simple stress myocardial perfusion imaging. (author)

  13. Clinical evaluation of efonidipine hydrochloride in angina pectoris. Evaluation in exercise 201Tl myocardial scintigraphy

    International Nuclear Information System (INIS)

    Clinical usefulness of once-daily administration of 20 to 60 mg of efonidipine hydrochloride and coronary hemodynamics during exercise 201Tl myocardial scintigraphy were investigated in patients with angina pectoris. Out of 11 patients enrolled in this study, 9 patients were included in the evaluation of patients' impression, in improvement rating in subjective symptoms, in the analysis of the exercise test, in the improvement rating of images on 201Tl myocardial scintigraphy, and in the global improvement rating, while 10 patients were included in the overall safety rating. Four patients in improvement rating in subjective symptoms, 2 in improving rating in the exercise test, and 5 in the global improvement rating were rated 'improved' or better. In the improvement rating on the exercise 201Tl myocardial scintigraphy image, reduction of the image was observed in 5 patients, 3 out of which were evaluated as 'improved' or better. A distinctive reduction of ischemic regions was observed in 2 patients out of the 3. A significant decrease in the number of angina pectoris events and a decreasing tendency in consumption of fast-acting nitrates were observed in spite of the low number of the patients studied. An adverse effect was observed in 1 patient and abnormal laboratory values were observed in 2 patients which were improved promptly after withdrawal of the drug. It was in 7 patients evaluated as 'no problem', while in 4 patients it was 'no problem', while in 4 patients it was evaluated as 'useful' or more. (author)

  14. Evaluation of myocardial viability following acute myocardial infarction using 201Tl SPECT after thallium-glucose-insulin infusion. Comparison with 18F-FDG positron emission tomography

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate myocardial viability in patients after acute myocardial infarction (AMI). We compared 201Tl SPECT after 201Tl with GIK (10% glucose 250 ml, insulin 5 U and KCI 10 mEq) infusion (GIK-201Tl) with resting 201Tl and 99mTc-pyrophosphate (PYP) dual SPECT, positron emission computed tomography (PET) using 18F-fluorodeoxyglucose (18F-FDG) in 21 patients with their first AMI, who all underwent successful reperfusion. GIK-201Tl SPECT, 201Tl and 99mTc-PYP dual SPECT were done within 10 days after admission and 18F-FDG-PET was performed at 3 weeks. GIK-201Tl SPECT was obtained after 30 min of GIK-201Tl infusion. 18F-FDG (370 MBq) was injected intravenously after oral glucose (1 g/kg) loading, and then PET was obtained. PET and SPECT images were divided into 20 segments. Regional tracer uptake was scored using a 4-point scoring system (3=normal to 0=defect), and summed to a regional uptake score (RUS). Regional area means the infarcted area in which 99mTc-PYP accumulated. The number of decreased uptake segments (ES) was then determined. The infarcted area was defined as the area of 99mTc-PYP uptake. The ESs for the GIK-201Tl and 18F-FDG-PET images were significantly lower than the number of 99mTc-PYP uptake segments. The RUS for GIK-PYP uptake segments. The RUS for GIK-201Tl was higher than that for resting-201Tl imaging and similar to those for 18F-FDG-PET. In the detection of myocardial viability following AMI, GIK-201Tl imaging is useful with findings similar to those of 18F-FDG-PET. (author)

  15. Gamma radiation measurements and Monte Carlo computations following myocardial perfusion imaging with 201Tl.

    Science.gov (United States)

    Clouvas, A; Xanthos, S

    2012-12-01

    In the current study, the time-dependent retention of (201)Tl-thallous chloride (111 MBq) was measured in a 56-y-old man undergoing myocardial perfusion imaging. For 23 d following the (201)Tl injection, total-body retained activity was measured by (i) in situ gamma spectrometry using a portable high-purity germanium (HPGe) detector and (ii) ex vivo urine radioassay using a shielded HPGe detector. The time-dependent decrease in total-body activity followed a monoexponential function, exp(-0.011 t), with an excellent correlation (R(2)=0.9988) between the experimental data and the fitted values. The effective half-life, Teff, of (201)Tl (physical half-life, Tph: 72.9 h) was therefore 63 h and the biological half-life, Tb, 463 h=19.3 d, identical to those measured in the same patient in 1997 (i.e. 14 y ago). The time-dependent decrease in the urine activity concentration, which followed a monoexponential function, exp(-0.0115 t), corroborated the foregoing results. The correlation (R(2)=0.9939) between the experimental data and the fitted values was again excellent. The effective half-life, Teff, was 60.26 h and the biological half-life, Tb, 348 h=14.5 d. Monte Carlo simulation using a simple model of the patient as a unit-density cylinder filled with water and containing a uniform distribution of (201)Tl yielded photon flux results in reasonable agreement with the measured data. PMID:22611205

  16. 201Tl myocardial imaging in patients with pulmonary hypertension

    International Nuclear Information System (INIS)

    The appearance of the right ventricular myocardium on thallium 201 myocardial perfusion images was evaluated in patients with chronic pulmonary hypertension and compared to patients without pulmonary hypertension. Four groups of patients were studied: (1) eight normals, (2) five patients with angiographically documented coronary artery disease and normal pulmonary artery pressures, (3) ten patients with moderate to severe pulmonary parenchymal or vascular disease and documented pulmonary hypertension and (4) eight patients with chronic left ventricular dysfunction and pulmonary hypertension discovered during cardiac catheterization. The right ventricular free wall was visualized on the thallium 201 myocardial perfusion image in only one of eight normals (group 1) and in only one of the five patients with coronary artery disease (group 2) and measured 0.5 cm and 0.9 cm in thickness, respectively. In patients with documented pulmonary hypertension the right ventricle was visualized on low contrast thallium 201 myocardial perfusion image in all patients. The apparent right ventricular free wall thickness measured from the ungated thallium 201 myocardial perfusion images was 1.7 +- 0.3 cm in group 3 and 1.5 +- 0.2 cm in group 4. Right ventricular hypertrophy was detected by electrocardiography in only five of ten patients in group 3 and only one of eight patients in group 4. Thallium 201 myocardial perfusion imaging appears to be a useful technique for assessing the effeca useful technique for assessing the effects of chronic pulmonary hypertension on the right ventricular myocardium

  17. Myocardial reversibility detection. Rest NTG 99mTc-MIBI versus 201Tl reinjection. Preliminary results

    International Nuclear Information System (INIS)

    This study test whether sublingual administration of nitroglycerin (NTG) could improve the capability of 99mTc-MIBI to detect reversibility in exercise-induced perfusion defects and to compare it with the 201Tl stress-redistribution-reinjection protocol. Twenty-one patients with previous myocardial infarction were submitted to exercise, rest and NTG rest 99mTc-MIBI imaging (3-day protocol). The patients also underwent exercise, redistribution and reinjection 201Tl myocardial scintigraphy. A total of 273 myocardial segments were analyzed: 76 (28%) had irreversible defects on stress-rest 99mTc-MIBI, 60 (79%) appeared as fixed defects and 16 (21%) were reversible on NTG rest 99mTc-MIBI. Of the 78 myocardial segments with irreversible defects on standard stress-redistribution thallium cardiac imaging, 63 (81%) did not change and 15 (19%) demonstrated enhanced uptake of thallium after reinjection. Data show that rest NTG 99mTc-MIBI study improves the detection of reversible myocardium versus standard exercise/rest 99mTc-MIBI and achieve similar results than 201TI reinjection protocol. (author)

  18. 201Tl myocardial perfusion in the management of transplanted heart

    International Nuclear Information System (INIS)

    A semi quantitative method with thallium has been applied in the management of cardiac transplants. In all, 142 scans were performed in 20 patients and were arranged in 3 groups that represent respectively all controls performed to the transplants (G1), and a selection of the scans obtained during the 1st rejection episode in each patient (G2) and the 2nd if present (G3). A heart/lung index was calculated through early and late images (IA, IB,) obtained 5 min and 4 h post injection of thallium. A decrease in IA was detected during acute rejection in all groups. This fall was statistically significant from the mild to moderate rejection degree in G1 (P3 (PB was not modified with rejection. Comparing the biopsies with and without edema, in the absence of rejection, it has been proved that the intra myocardial edema can produce a decrease in IA (PA is a simple and sensitive index to evaluate the graft, although intra myocardial edema can reduce its specificity. (orig.)

  19. Experimental regional myocardial ischaemia and myocardial uptake of potassium analogues; intercomparison of 42K, 86Rb and 201Tl

    International Nuclear Information System (INIS)

    The uptake of 42K, 86Rb and 201Tl by non-ischaemic and ischaemic myocardium was determined in rats with coronary artery ligature lasting 10, 30, 60 and 120 min, and in control rats without ischaemia. Whereas the myocardial concentration of 201Tl and 42K in control rats was similar and higher than that of 86Rb, 201Tl was superior to the other two radionuclides due to its significantly higher accumulation in non-ischaemic myocardium and the higher ratio of non-ischaemic to ischaemic radioactivity. The 86Rb accumulation in non-ischaemic myocardium and non-ischaemic/ischaemic ratio began to decrease from its maximum at 10 min. 201Tl, 42K and 86Rb blood levels in intact animals decreased rapidly after intravenous injection to low and nearly stabilized values at 5 min. Na+K+-ATPase activity in the ischaemic myocardium was high in the acutely ischaemic myocardium and decreased to below control levels after 4 h of ischaemia; changes in activity could not influence the low uptake of potassium analogues in fresh ischaemic myocardium. (orig.)

  20. Comparative study of 201Tl reinjection mycoardial imaging and late imaging after reinjection for detecting myocardial viability

    International Nuclear Information System (INIS)

    PURPOSE: To compare 201Tl reinjection imaging with late imaging in detecting myocardial viability. METHODS: 62 patients with myocardial infarction underwent 201Tl exercise, 3?5 hours redistribution, 16?35 minutes and 12?19 hours post 201Tl reinjection mycoardial tomography imaging. After imaging, percutaneous transluminal coronary angioplasty (PTCA) were performed in 15 patients, and then exercise-redistribution myocardial imaging were repeated. RESULTS: 62 patients had 126 segments of irreversible defects on stress-redistribution imaging, 48 segments showed radioactive filling at 16?35 minutes post-reinjection. The detecting rate of myocardial viability was 38.1% (48/126). 51 segments presented redistribution on 12?19 hours late imaging, the detecting rate of myocardial viability was 40.5% (51/126). There were no significant difference in the detecting rate between them (x2 0.16, P>0.05). But in combination of both methods, there were 62 segments refilling, thereby detecting rate was enhanced to 49.2% (62/126). In 15 patients who had PTCA, out of 17 segments were discovered to be viable before PTCA. After PTCA 12 segments had an improved perfusion of 201Tl, the positive predictive accuracy was 70.6%. Out of 11 segments were discovered to be infarcted, 9 segments had non-improved 201Tl perfusion after PTCA, the negative predictive accuracy was 81.8%. CONCLUSION: There were no significant diffe There were no significant difference in the detecting rate of myocardial viability between 2'01Tl reinjection and late imaging. In combination of both methods the detecting rate can be enhanced

  1. Scintigraphically determined myocardial blood flow by means of 201Tl in single and multiple vascular lesions

    International Nuclear Information System (INIS)

    100 patients with suspected coronary heart disease were examined for local storage defects in Tl scintigram in order to determine the clinical importance of 201Tl myocardial scintigraphy in comparison to heart catheterization. As to the sensitivity Tl scintigraphy proved to be superior to exercise electrocardiography with 89.3% to 63.6%. Tl scintigraphy was 100% sensitive in cases with 1 or 2 vessels affected compared to ECG with 47.0% and 58.8% resp. In patients with 3 vessels affected the sensitivity of both the methods was nearly equal. The myocardial scintigraphy, however, revealed more false positive results than ergometry. In spite of the diagnostic advantage, myocardial scintigraphy is not suited for screening tests. The range of indication of Tl scintigraphy in suspected as well as in established coronary heart disease is discussed

  2. Myocardial scintigraphic studies with 123I-MIBG, 201Tl and 99mTc-PYP in patients with cardiac amyloidosis

    International Nuclear Information System (INIS)

    Myocardial scintigraphic studies, using 123I-metaiodobenzylguanidine (MIBG), 99mTc-pyrophosphate (PYP) and 201Tl were performed in 4 patients with cardiac amyloidosis. In MIBG myocardial images, 2 patients with familial amyloid polyneuropathy (FAP) showed complete or partial defect and the other 2 with primary amyloidosis had normal myocardial uptake of MIBG. In PYP myocardial images, diffuse myocardial uptake of PYP was mild in 2 patients with FAP and moderate in the other 2. 201Tl myocardial images revealed normal myocardial uptake of 201Tl in 2 patients with FAP and 1 with primary amyloidosis, and intense myocardial uptake in the other one with primary amyloidosis. These results suggest that myocardial scintigraphies with PYP and 201Tl may be useful for the detection of cardiac amyloidosis and estimation of its pathophysiology. And MIBG myocardial scintigraphy may provide useful information about sympathetic nerve abnormalities which vary with type of the fibril protein, clinical syndromes and disease process of cardiac amyloidosis. (author)

  3. Influence of increased 201Tl lung uptake on the myocardial viability of the patients with dilated cardiomyopathy under congestive heart failure

    International Nuclear Information System (INIS)

    Influence of increased 201Tl lung uptake on the myocardial viability was studied in 15 patients with dilated cardiomyopathy under congestive heart failure. Rest and 4 hours delayed 201Tl SPECT were obtained. At the same time anterior planar images were collected. In 10 patients of 15 patients 201Tl lung heart ratio in SPECT (LHR) was larger than that in planar images. Maximal 201Tl lung uptake was noted at the lower left lung adjacent to the heart. In the delayed images 201Tl lung uptake diminished. In 10 patients the value of LHR in the delayed images was less than 0.5. By comparing initial images with delayed images it was proved to be difficult to determine the myocardial margin adjacent to the increased 201Tl lung uptake. In 2 patients lateral defects were concealed by the increased 201Tl lung uptake. In the remaining patients lateral wall was similar to the hypertrophic myocardium. The effect of scatter due to the increased 201Tl lung uptake was noted in the neighboring myocardium. In most cases %201Tl uptake in the septum was relatively depressed by increased %201Tl uptake in the lateral wall. In the delayed images pseudo-redistribution was noted in the septum. Mean value of differences in %201Tl uptake between initial and delayed images was 8(2-15)%. It was concluded that in case of increased 201Tl lung uptake SPECT could not accurTl lung uptake SPECT could not accurately estimate myocardial viability by initial images and delayed images were necessary for precise estimation. (author)

  4. Influence of increased [sup 201]Tl lung uptake on the myocardial viability of the patients with dilated cardiomyopathy under congestive heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takeshi; Nakano, Hajime; Katoh, Kazuzo (Cardiovascular Inst., Tokyo (Japan))

    1992-11-01

    Influence of increased [sup 201]Tl lung uptake on the myocardial viability was studied in 15 patients with dilated cardiomyopathy under congestive heart failure. Rest and 4 hours delayed [sup 201]Tl SPECT were obtained. At the same time anterior planar images were collected. In 10 patients of 15 patients [sup 201]Tl lung heart ratio in SPECT (LHR) was larger than that in planar images. Maximal [sup 201]Tl lung uptake was noted at the lower left lung adjacent to the heart. In the delayed images [sup 201]Tl lung uptake diminished. In 10 patients the value of LHR in the delayed images was less than 0.5. By comparing initial images with delayed images it was proved to be difficult to determine the myocardial margin adjacent to the increased [sup 201]Tl lung uptake. In 2 patients lateral defects were concealed by the increased [sup 201]Tl lung uptake. In the remaining patients lateral wall was similar to the hypertrophic myocardium. The effect of scatter due to the increased [sup 201]Tl lung uptake was noted in the neighboring myocardium. In most cases %[sup 201]Tl uptake in the septum was relatively depressed by increased %[sup 201]Tl uptake in the lateral wall. In the delayed images pseudo-redistribution was noted in the septum. Mean value of differences in %[sup 201]Tl uptake between initial and delayed images was 8(2-15)%. It was concluded that in case of increased [sup 201]Tl lung uptake SPECT could not accurately estimate myocardial viability by initial images and delayed images were necessary for precise estimation. (author).

  5. Myocardial imaging with 201Tl at rest and during exercise. Comparison with coronary arteriography and resting and stress electrocardiography

    International Nuclear Information System (INIS)

    Myocardial imaging with intravenous thallium-201 (201Tl) was performed at rest and following maximal treadmill exercise in 101 patients with suspected coronary artery disease. Results were interpreted from Polaroid scintiphotos by three independent observers with complete interobserver agreement in 79%. Of 25 patients with no or insignificant coronary artery disease (201Tl image defect, one (4%) had an exercise 201Tl defect, none had an ECG Q wave, and four (16%) had exercise ST-segment depression. Among 76 patients with coronary artery disease (greater than or equal to 50% diameter stenosis), 58 (76%) had a defect on either the rest or exercise 201Tl image. The proportion of patients with an exercise image defect (50/76, 66%) was greater than the proportion with exercise ST depression alone (34/76, 45%; P 201Tl is easily accomplished with readily available imaging equipment. The image data enhanced the diagnostic sensitivity of stress electrocardiography, and provided spatial identificrdiography, and provided spatial identification of the abnormal segment(s) of myocardium

  6. Noninvasive detection and localization of coronary stenoses in patients: comparison of resting dipyridamole and exercise 201Tl myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Two noninvasive tests to detect and localize coronary stenoses were compared in a fully blinded protocol. 201Tl myocardial perfusion imaging (MPI) following maximal treadmill exercise and pharmacologic coronary vasodilation with intravenous dipyridamole (DP) was performed in 33 patients. 201Tl imaging defects in six myocardial perfusion regions were correlated with stenoses in their respective vascular distributions. Disease severity was determined with coronary arteriograms using a computer-assisted method. 198 myocardial regions were evaluated; 101 were supplied by at least one major artery with a greater than or equal to 50% stenosis (luminal diameter narrowing). The sensitivity and specificity for detecting a greater than or equal to 50% stenosis were 85% and 64% (p less than 0.005), respectively, for DP and 84% and 68% (p less than 0.005) for exercise-201Tl imaging. A particular combination of anterior and septal imaging defects was useful in detecting left anterior descending artery stenoses proximal to its first septal branch. DP administration was safe in this group of patients; however, 42% experienced transient chest pain. Although the overall sensitivity and specificity of the two methods were not significantly different, DP-MPI appeared more sensitive than exercise-MPI (70% vs 52%, p less than 0.01) in detecting coronary stenoses in the 40% to 60% range. DP-201Tl MPI provides a useful alternative test for potentiides a useful alternative test for potential coronary disease patients unable to perform maximal exercise

  7. Quantitative evaluation of right ventricular overload in cor pulmonale using 201Tl myocardial SPECT

    International Nuclear Information System (INIS)

    To determine quantitatively the discriminant and characteristics of cor pulmonale, 201Tl myocardial perfusion SPECT was performed in 16 patients with chronic obstructive pulmonary disease (COPD) and 7 with restrictive pulmonary disease (RPD). One section of the short-axis SPECT image in which the right ventricle was most clearly visualized was selected. Tl-score was defined as the ratio of the sum of counts in the region of interest (ROI) at the anterior, mid, and posterior regions of the right ventricular free wall to the sum of counts in ROI at the posterior, lateral, and anterior walls of the left ventricle, and the anterior and posterior regions of the interventricular septum. In the group of COPD patients, Tl-score was positively correlated with mean pulmonary arterial pressure (mPAP), total pulmonary vascular resistance (TPR), and arterial carbon dioxide tension (PaCO2), while it was inversely correlated with arterial oxygen tension (PaO2). However, there was no significant correlation between Tl-score and mPAP, TPR, PaCO2, and PaO2 in the group of RPD patients. In assessing pulmonary hypertension as defined by mPAP over 20 mmHg, a Tl-score greater than 0.25 was useful with a sensitivity of 69% and a specificity of 90%. The occurrence of cor pulmonale is a major factor in determining the prognosis of COPD patients. It was concluded that 201Tl myocardial SPECT is useful for evaluating right ventricECT is useful for evaluating right ventricular overload quantitatively, as well as for assessing core pulmonale, especially in COPD patients, since the ratio of Tl counts in the right and left ventricles was significantly correlated with right cardiopulmonary hemodynamic parameters. (N.K.)

  8. Absolute quantitation of myocardial blood flow with 201Tl and dynamic SPECT in canine: optimisation and validation of kinetic modelling

    International Nuclear Information System (INIS)

    201Tl has been extensively used for myocardial perfusion and viability assessment. Unlike 99mTc-labelled agents, such as 99mTc-sestamibi and 99mTc-tetrofosmine, the regional concentration of 201Tl varies with time. This study is intended to validate a kinetic modelling approach for in vivo quantitative estimation of regional myocardial blood flow (MBF) and volume of distribution of 201Tl using dynamic SPECT. Dynamic SPECT was carried out on 20 normal canines after the intravenous administration of 201Tl using a commercial SPECT system. Seven animals were studied at rest, nine during adenosine infusion, and four after beta-blocker administration. Quantitative images were reconstructed with a previously validated technique, employing OS-EM with attenuation-correction, and transmission-dependent convolution subtraction scatter correction. Measured regional time-activity curves in myocardial segments were fitted to two- and three-compartment models. Regional MBF was defined as the influx rate constant (K1) with corrections for the partial volume effect, haematocrit and limited first-pass extraction fraction, and was compared with that determined from radio-labelled microspheres experiments. Regional time-activity curves responded well to pharmacological stress. Quantitative MBF values were higher with adenosine and decreased after beta-blocker compared to a resting condition. MBFs obtacompared to a resting condition. MBFs obtained with SPECT (MBFSPECT) correlated well with the MBF values obtained by the radio-labelled microspheres (MBFMS) (MBFSPECT = -0.067 + 1.042 x MBFMS, p 201Tl and dynamic SPECT. (orig.)

  9. Lung activity in 201Tl-myocardial scintigraphy: Distribution and correlation with hemodynamic parameters

    International Nuclear Information System (INIS)

    The aim of this study was 1. to investigate whether the pulmonary activity in 201Tl myocardial scintigraphy can be accurately quantitied from the anterior SPECT projection, 2. to determine the pattern of the intrapulmonary Tl distribution, and 3. to assess the influence of parameters of left ventricular function on the lung/heart ratio (LHR). Scintigraphic images of 85 patients were analysed. In 24 patients planar anterior imaging of the thorax was performed in addition to myocardial SPECT, in 41 patients radionuclide ventriculography was performed with 4 weeks after Tl scintigraphy. In conclusion: 1. Pulmonary Tl-content can be quantitated from the anterior SPECT projection with sufficient accuracy, 2. a lower thallium activity was registered over the apical part of the lung as compared to the basal part, and 3. in the multiple regression analysis the left ventricular ejection fraction (LVEF) during exercise and heart rate during exercise (HRex) exhibit the strongest relation to LHR. After correction with regard to HRex the elevated LHR points to a pathological LVEF during exercise. (orig.)

  10. Coronary artery disease detected noninvasively by dipyridamole-loading 201Tl myocardial scintigraphy in elderly patients

    International Nuclear Information System (INIS)

    To evaluate the usefulness in diagnosing coronary artery disease (CAD), dipyridamole-loading 201Tl myocardial scintigraphy was performed for 52 elderly patients (65 - 92 years, mean: 72 years), and the results were compared with data from the treadmill exercise tests. 1. Thirty-five patients could not tolerate adequate exercise tests. Seven of them had reversible defects; six, fixed (irreversible) ones. Dipyridamole scintigraphy is therefore applicable in detecting CAD among patients with suspected CAD who are unable to perform adequate exercise tests. 2. Four of 16 patients with positive exercise tests had no reversible defects; the exercise results in three were regarded as false positives. 3. Seventeen patients experienced chest pain; 12 had ST depression during dipyridamole loading. There were no serious complications, but seven patients required aminophylline. 4. We demonstrated previously that the sensitivity and specificity of dipyridamole scintigraphy in detecting CAD were 90 % and 92 %, respectively, in patients with chest pain undergoing coronary angiography. These results were superior to those of conventional exercise myocardial scintigraphy. Therefore, dipyridamole scintigraphy is regarded as a safe and useful method for detecting CAD, particulary in elderly patients who have ST and T wave abnormalities but cannot tolerate exercise test adequately. (author)

  11. Improvement of myocardial perfusion detected by 201Tl scintigraphy on cardiac rehabilitation for patients with coronary artery disease

    International Nuclear Information System (INIS)

    The effect of cardiac rehabilitation (mean 70±48 months) on myocardial perfusion was assessed using thallium-201 (201Tl) exercise study in 63 patients with coronary artery disease (CAD). Subjects were those in a rehabilitation group (Rh=42) participating in supervised sports training two to three times per week and the control group (Ct=21) not taking active daily exercise. The interval between two 201Tl SPECT studies was 19±16 months. After physical training, total duration of the exercise test increased from 443±112 to 536±121 seconds (+19%) in the Rh group, and from 484±129 to 432±115 seconds in the Ct group (-10.7%) (p2 to 269.8±58 x 102 in the Rh group and decreased from 218.7±40 x 102 to 216.6±76 x 102 (p201Tl myocardial perfusion defect on exercise improved more in 54.8% (stress 59.5%, rest 35.7%) in the Rh group than in the Ct group (9.5%, p201Tl perfusion defect decreased from 68 (23.1%) to 49 regions (16.7%) of 294 total myocardial regions in the Rh group on exercise. However. it increased from 39 (26.5%) to 44 (29.9%) regions of 147 regions in the Ct group (p<0.01). Thus, cardiac rehabilitation increases exercise tolerance with improvement of myocardial perfusion. suggesting that cardiac rehabilitation is an advisable and effective treatment for patients with ischemic heartfor patients with ischemic heart disease. (author)

  12. Cost-effectiveness of exercise 201Tl myocardial SPECT in patients with chest pain assessed by decision-tree analysis

    International Nuclear Information System (INIS)

    To evaluate the potential cost-effectiveness of exercise 201Tl myocardial SPECT in outpatients with angina-like chest pain, we developed a decision-tree model which comprises three 1000-patients groups, i.e., a coronary arteriography (CAG) group, a follow-up group, and a SPECT group, and total cost and cardiac events, including cardiac deaths, were calculated. Variables used for the decision-tree analysis were obtained from references and the data available at out hospital. The sensitivity and specificity of 201Tl SPECT for diagnosing angina pectoris, and its prevalence were assumed to be 95%, 85%, and 33%, respectively. The mean costs were 84.9 x 104 yen/patient in the CAG group, 30.2 x 104 yen/patient in the follow-up group, and 71.0 x 104 yen/patient in the SPECT group. The numbers of cardiac events and cardiac deaths were 56 and 15, respectively in the CAG group, 264 and 81 in the follow-up group, and 65 and 17 in the SPECT group. SPECT increases cardiac events and cardiac deaths by 0.9% and 0.2%, but it reduces the number of CAG studies by 50.3%, and saves 13.8 x 104 yen/patient, as compared to the CAG group. In conclusion, the exercise 201Tl myocardial SPECT strategy for patients with chest pain has the potential to reduce health care costs in Japan. (author)

  13. Serial assessment of denervated but viable myocardium following acute myocardial infarction in dogs using iodine-123 metaiodobenzylguanidine and thallium-201 chloride myocardial single photon emission tomography

    International Nuclear Information System (INIS)

    Iodine-123 metaiodobenzylguanidine (mIBG) is taken up by sympathetic nerve endings, allowing scintigraphic imaging of myocardial sympathetic innervation. We investigated the denervated but viable canine myocardium after acute myocardial infarction by serial mIBG and thallium-201 chloride (201TlCl) single photon emission tomography (SPET). In 12 dogs, acute myocardial infarction was produced by ligation of the left circumflex coronary artery. Images of mIBG and thallium SPET were obtained 6 h, 1, 4 and 6 weeks later. The defect size was calculated in percentage points from short axial views, and the 123I-mIBG/201TlCl ratio was determined. The uptake ratio was high at 1 week but gradually decreased. Three dogs were killed at each time point, and tissue samples were obtained from infarcted (both 201TlCl and 123I-mIBG defects), peri-infarcted (123I-mIBG defect and 201TlCl normal) and normal myocardium (both mIBG and 201TlCl normal). The changes in tissue content of noradrenaline in these lesions were measured. Noradrenaline tissue content gradually recovered in the pre-infarcted area. However, no recovery was noted in the infarcted area at 6 weeks. We conclude that sympathetic denervation and re-innervation occur following acute myocardial infarction, and the denervated but viable myocardium could be detected non-invasively by combined mIBG and thallium SPET. (orig.) thallium SPET. (orig.)

  14. Clinical implications of increased lung uptake of 201Tl during exercise scintigraphy 2 weeks after myocardial infarction

    International Nuclear Information System (INIS)

    To determine the prevalence and clinical significance of increased lung 201Tl uptake during submaximal exercise myocardial scintigraphy performed 2 weeks after acute myocardial infarction, 61 patients underwent submaximal exercise testing (target heart rate, 120 beats/min), multigated blood pool imaging at rest and coronary angiography before hospital discharge. Thallium lung uptake on the initial anterior projection image was graded qualitatively by comparing the intensity of 201Tl activity in the lungs with that in the mediastinum. In 39 patients (64 percent), it was normal (equal to mediastinal activity) and in 22 (36 percent), it was increased (greater than mediastinal activity). Compared with patients with normal lung uptake, those with increased uptake had a greater prevalence of prior infarction (13 versus 36 percent, probability [p] less than 0.05), less global cardiac reserve as assessed by the four level New York Heart Association classification (p less than 0.05), more advanced Killip class in the coronary care unit (p less than 0.05), a higher Norris coronary prognostic index (2.6 +/- 1.9 versus 4.6 +/- 2.3 [mean +/- standard deviation], p less than 0.01), failure to achieve the target heart rate because of dyspnea, fatigue or angina (36 versus 86 percent, p less than 0.01), a greater prevalence of exercise-induced S-T segment depression (18 versus 45 percent, p less than 0.05), a greater number of anterior 201Tl myocardialer of anterior 201Tl myocardial defects (p less than 0.05); a lower radionuclide ejection fraction at rest (50.4 +/- 6.1 versus 39.6 +/- 9.3 percent, p less than 0.01) and a greater number of asynergic left ventricular segments (p less than 0.05). Thus, the occurrence of increased lung 201Tl uptake during submaximal exercise scintigraphy in the early postinfarction period is frequent and appears to be a marker of severe and functionally more important coronary artery disease associated with left ventricular dysfunction

  15. Comparison of myocardial 201Tl clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication

    International Nuclear Information System (INIS)

    Recently the quantitation of regional 201Tl clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although 201Tl clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial 201Tl activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean 201Tl clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those whn interpreting clearance rates in those who do not exercise to an accepted end point

  16. Thallium chloride 201Tl combined with single photon emission computed tomography (SPECT) in the evaluation of vestibular schwannoma growth

    DEFF Research Database (Denmark)

    Charabi, Samih Ahmed; Lassen, N A

    1997-01-01

    Thallium chloride 201Tl combined with SPECT was performed in a series of 29 patients with neuroradiological evidence of vestibular schwannoma (VS). The relative tumor uptake (U) and relative tumor concentration (C) of the radiotracer 201Tl was determined, and the cerebellum served as a reference. The relative tracer concentration and uptake were correlated to tumor volume determined by gadolinium DTPA enhanced MR, to prediagnostic duration of symptoms, to tumor vascularity expressed by the average number of intratumoral vessels using the endothelial marker CD31, and to the proliferative activity in the tumors expressed by positive staining with the monoclonal antibody MIB-1 for Ki-67. A positive 201TI enhancement was detected in 17 tumors (n = 17). Tumors U and C were statistically unrelated to tumor volume (p = 0.236 and p = 0.439). SPECT demonstrated all tumors > 0.8 cm3, but it had its limitation as a diagnostic modality of small intracanalicular tumors, when compared with gadolinium DTPA enhanced MR. Relating U and C in all tumors (n = 29) and the prospectively registered data on the prediagnostic duration of symptoms, a statistical significance was found (p = 0.012 and p = 0.015). No statistically significant correlation was observed between U and C and the proliferative activity of the tumors expressed by positive staining with the monoclonal antibody MIB-1 for Ki-67 (p = 0.063 and p = 0.086). A statistically significant correlation was noted between C and U in the operated group (n = 12) and tumor vascularity expressed by the average number of the intratumoral vessels (p = 0.003 and p = 0.014). SPECT was found to be superior to MR in determining VS growth potentials as it expresses tumor vascularity, which is essential for tumor growth. It seems that we now have an in vivo functional radiological modality capable of providing data on VS vascularity and determination of growth potential in the individual tumor. A high radioactive tracer uptake in the tumor corresponded to high tumor vascularity, indicating a high growth rate and vice versa.

  17. [Myocardial scintigraphic studies with 123I-MIBG, 201Tl and 99mTc-PYP in patients with cardiac amyloidosis].

    Science.gov (United States)

    Fujii, T; Tanaka, M; Yazaki, Y; Kitabayashi, H; Koizumi, T; Hongo, M; Sekiguchi, M; Itoh, A; Gomi, T; Yano, K

    1997-11-01

    Myocardial scintigraphic studies, using 123I-metaiodobenzylguanidine (MIBG), 99mTc-pyrophosphate (PYP) and 201Tl were performed in 4 patients with cardiac amyloidosis. In MIBG myocardial images, 2 patients with familial amyloid polyneuropathy (FAP) showed complete or partial defect and the other 2 with primary amyloidosis had normal myocardial uptake of MIBG. In PYP myocardial images, diffuse myocardial uptake of PYP was mild in 2 patients with FAP and moderate in the other 2. 201Tl myocardial images revealed normal myocardial uptake of 201Tl in 2 patients with FAP and 1 with primary amyloidosis, and intense myocardial uptake in the other one with primary amyloidosis. These results suggest that myocardial scintigraphies with PYP and 201Tl may be useful for the detection of cardiac amyloidosis and estimation of its pathophysiology. And MIBG myocardial scintigraphy may provide useful information about sympathetic nerve abnormalities which vary with type of the fibril protein, clinical syndromes and disease process of cardiac amyloidosis. PMID:9455044

  18. [Interesting PYP, 201Tl, MIBG, AM and BMIPP myocardial SPECT images in a patient under successful reperfusion therapy].

    Science.gov (United States)

    Tanaka, T; Aizawa, T; Katou, K; Ogasawara, K; Kirigaya, H; Okamoto, K; Hosoi, H; Oota, A

    1992-06-01

    Various types of radiopharmacons such as 201Tl, 99mTc-pyrophosphate(PYP), 123I-metaiodobenzyl-guanidine(MIBG), 111In-antimyosin Fab (AM) and 123I-beta-methyl iodophenyl pentadecanoic acid (BMIPP) were applied to a patient under successful reperfusion therapy. In the patient, elevated serum enzyme activity region in the subacute phase. Ten months after the ischemic event, AM uptake was noted at the region which maintained contractility. Two years after the ischemic event, depressed BMIPP uptake and delayed washout were noted at the apical region and the basal anteroseptal region. From these findings, the following conclusions were reached. Depressed 201Tl uptake was noted in the salvaged jeopardized myocardium. The lesions noted in the MIBG images showed depressed myocardial norepenephrine activity. This suggested that depressed sympathetic nervous function caused by severe ischemia persisted long after both myocardial perfusion and myocardial contractility had been restored. From abnormal AM uptake in the contractile myocardium myocardial cell damage, which permitted AM uptake, was persistent ten months after the ischemic event. Depressed BMIPP uptake and delayed washout suggested that abnormal fatty acid metabolism caused by severe ischemia was persistent. Severe ischemia caused various types of pathological states in the myocardium and radioisotope image was useful for studying these states. PMID:1535723

  19. Diagnosis of myocardial infarction using single photon emission computed tomography

    International Nuclear Information System (INIS)

    For diagnosing myocardial infarction by myocardial scintigraphy using 201TlCl, the following two items were compared: 1) The diagnostic accuracy of visual evaluation of myocardial planar images versus that of single photon emission computed tomography (SPECT) images. 2) The diagnostic accuracy of qualitative and quantitative evaluations of SPECT images. The planar and SPECT methods were performed for 81 subjects consisting of 41 patients having myocardial infarction and 40 normal persons. Receiver operator characteristic (ROC) analysis, which is most objective in evaluation of visual diagnosis, was also used. To analyze quantitative diagnosis by ROC analysis, the normal range of circumferential profile analysis of myocardial short-axial tomography was determined by assessing five step divisions (less than 1SD, 1-1.7SD, 1.7-2.3SD, 2.3-3SD, and more than 3SD) from 10 normal cases. Four physicians and three laboratory technicians familiar with myocardial images diagnosed the myocardial planar images and SPECT images individually. The results were analyzed and the ROC curves were constructed. The results indicated that image diagnosis by SPECT was superior to that by the visual planar method for all persons. The physicians who had more experience in diagnosing myocardial images made more accurate diagnosis. However, quantitative SPECT image diagnosis was superior to visual SPECT image diagnosis. Thus, with the input of data of the normal range of quantitative Sdata of the normal range of quantitative SPECT image diagnosis into the computer, the prospects of accurate computer assessments of myocardial infarctions were posed. Furthermore, an area of low myocardial perfusion, less than 2 standard deviations of the normal range, showed the degree and extent of infarction, which facilitated pinpointing the site, extent and degree of the myocardial infarction in a three-dimensional concept, and the location of the corresponding coronary artery lesion, as well. (author)

  20. Comparison of adenosine stress and exercise stress 201Tl myocardial perfusion imaging for diagnosis of coronary heart disease

    International Nuclear Information System (INIS)

    Objective: The aim of this study was to compare the diagnostic values of adenosine and exercise stress 201Tl myocardial perfusion imaging for detecting coronary heart disease (CHD). Methods: 41 patients with suspected CHD were randomly divided into two groups. In one group adenosine stress was submitted, the exercise stress myocardial SPECT was performed in another. Coronary angiography (CAG) was performed in each patient within 2 weeks before or after SPECT. The result of CAG was taken as 'gold standard of CHD. They compared the diagnostic value of two methods. Results: In adenosine group, the sensitivity, specificity, positive predictive value, negative predictive value, accuracy are 92.86%, 57.14%, 81.25%, 80.00%, 80.95% respectively. In exercise stress group, are 100%, 60.0%, 71.43%, 100%, 80.00% respectively. Detection rates of coronary artery lesions were 66.67% and 72.22% in two groups respectively. Conclusion Adenosine stress testing and exercise stress testing 201Tl myocardial perfusion imaging may provide similar value for detection of CHD. (authors)

  1. Low-dose single acquisition rest {sup 99m}Tc/stress {sup 201}Tl myocardial perfusion SPECT protocol: phantom studies and clinical validation

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Thomas [RWTH Aachen University, Institute of Imaging and Computer Vision, Aachen (Germany); Backus, Barbra E.; Romijn, R.Leo [St. Antonius Hospital, Department of Nuclear Medicine, Nieuwegein (Netherlands); Wieczorek, Herfried [Philips Research, Eindhoven (Netherlands); Verzijlbergen, J.F. [St. Antonius Hospital, Department of Nuclear Medicine, Nieuwegein (Netherlands); Erasmus Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands)

    2014-03-15

    We developed and tested a single acquisition rest {sup 99m}Tc-sestamibi/stress {sup 201}Tl dual isotope protocol (SDI) with the intention of improving the clinical workflow and patient comfort of myocardial perfusion single photon emission computed tomography (SPECT). The technical feasibility of SDI was evaluated by a series of anthropomorphic phantom studies on a standard SPECT camera. The attenuation map was created by a moving transmission line source. Iterative reconstruction including attenuation correction, resolution recovery and Monte Carlo simulation of scatter was used for simultaneous reconstruction of dual tracer distribution. For clinical evaluation, patient studies were compared to stress {sup 99m}Tc and rest {sup 99m}Tc reference images acquired in a 2-day protocol. Clinical follow-up examinations like coronary angiography (CAG) and fractional flow reserve (FFR) were included in the assessment if available. Phantom studies demonstrated the technical feasibility of SDI. Artificial lesions inserted in the phantom mimicking ischaemia could be clearly identified. In 51/53 patients, the image quality was adequate for clinical evaluation. For the remaining two obese patients with body mass index > 32 the injected {sup 201}Tl dose of 74 MBq was insufficient for clinical assessment. In answer to this the {sup 201}Tl dose was adapted for obese patients in the rest of the study. In 31 patients, SDI and {sup 99m}Tc reference images resulted in equivalent clinical assessment. Significant differences were found in 20 patients. In 18 of these 20 patients additional examinations were available. In 15 patients the diagnosis based on the SDI images was confirmed by the results of CAG or FFR. In these patients the SDI images were more accurate than the {sup 99m}Tc reference study. In three patients minor ischaemic lesions were detected by SDI but were not confirmed by CAG. In one of these cases this was probably caused by pronounced apical thinning. For two patients no relevant clinical follow-up information was available for evaluation. The proposed SDI protocol has the potential to improve clinical workflow and patient comfort and suggests improved accuracy as demonstrated in the clinical feasibility study. (orig.)

  2. Low-dose single acquisition rest 99mTc/stress 201Tl myocardial perfusion SPECT protocol: phantom studies and clinical validation

    International Nuclear Information System (INIS)

    We developed and tested a single acquisition rest 99mTc-sestamibi/stress 201Tl dual isotope protocol (SDI) with the intention of improving the clinical workflow and patient comfort of myocardial perfusion single photon emission computed tomography (SPECT). The technical feasibility of SDI was evaluated by a series of anthropomorphic phantom studies on a standard SPECT camera. The attenuation map was created by a moving transmission line source. Iterative reconstruction including attenuation correction, resolution recovery and Monte Carlo simulation of scatter was used for simultaneous reconstruction of dual tracer distribution. For clinical evaluation, patient studies were compared to stress 99mTc and rest 99mTc reference images acquired in a 2-day protocol. Clinical follow-up examinations like coronary angiography (CAG) and fractional flow reserve (FFR) were included in the assessment if available. Phantom studies demonstrated the technical feasibility of SDI. Artificial lesions inserted in the phantom mimicking ischaemia could be clearly identified. In 51/53 patients, the image quality was adequate for clinical evaluation. For the remaining two obese patients with body mass index > 32 the injected 201Tl dose of 74 MBq was insufficient for clinical assessment. In answer to this the 201Tl dose was adapted for obese patients in the rest of the study. In 31 patients, SDI and 99mTc reference images resulted in equivalent clinical assessment. Significant differences were found in 20 patients. In 18 of these 20 patients additional examinations were available. In 15 patients the diagnosis based on the SDI images was confirmed by the results of CAG or FFR. In these patients the SDI images were more accurate than the 99mTc reference study. In three patients minor ischaemic lesions were detected by SDI but were not confirmed by CAG. In one of these cases this was probably caused by pronounced apical thinning. For two patients no relevant clinical follow-up information was available for evaluation. The proposed SDI protocol has the potential to improve clinical workflow and patient comfort and suggests improved accuracy as demonstrated in the clinical feasibility study. (orig.)

  3. Radionuclide diagnosis of dilated cardiomyopathy: a new approach to evaluate myocardial perfusion from 201Tl scintigraphic findings at rest and during dipyridamole test

    International Nuclear Information System (INIS)

    A method for quantitative determination of the percentage of left ventricular myocardial 201Tl isotope uptake at rest and during dipyridamole test was first used in patients with dilated cardiomyopathy and coronary heart disease complicated by circulatory insufficiency or chronic myocarditis. This method makes it possible to judge the level of myocardial blood flow and perfusion reserve in these diseases

  4. Serial 201Tl myocardial imaging after dipyridamole infusion: diagnostic utility in detecting coronary stenoses and relationship to regional wall motion

    International Nuclear Information System (INIS)

    After a 4-minute i.v. dipyridamole infusion, 0.14 mg/kg/min, serial 201Tl scans were obtained in 60 patients undergoing cardiac catheterization. Forty patients had significant (greater than or equal to 50% stenosis) coronary artery disease (CAD), and 20 patients had normal coronary arteries or trivial lesions. The images were graded qualitatively for thallium activity by three observers. Sensitivity was 93% (37 of 40) and specificity was 80% (16 of 20). The sensitivity and specificity of the 201Tl study were not affected by the extent of CAD, the presence of Q waves, or propranolol therapy. Twenty-seven of 37 patients who had initial defects (73%) had complete thallium redistribution of one or more defects. Patient-by-patient analysis using a regression model of all patients showed that the fate of a segmental thallium defect predicted abnormal wall motion by angiography better than ECG Q waves. The presence of propranolol therapy or collaterals did not significantly affect the thallium redistribution results. We conclude that qualitative interpretation by multiple observers of thallium images after dipyridamole infusion is a highly sensitive and specific test for CAD. After dipyridamole, as with exercise stress, the extent of thallium redistribution is related to the degree of myocardial wall motion abnormality

  5. Assessment of myocardial viability by exercise stress myocardial tomography with 201Tl

    International Nuclear Information System (INIS)

    Exercise stress (Ex) and redistribution (RD) myocardial tomography with Tl-201 has been widely used for evaluating myocardial viability. But recent studies have demonstrated that reinjection (ReI) study following RD study is necessary for detecting reversible ischemic myocardium. On the other hand, decreased myocardial washout of Tl-201 after Ex is an indicator of myocardial ischemia. So we have studied the usefulness of myocardial Tl-201 washout rate (WOR) for the evaluation of myocardial viability by comparing it with ReI images. Ex and RD myocardial tomographies were obtained immediately after Ex and 3 hours later. After RD study a small amount of Tl-201 was injected and ReI imaging was repeated. We studied 64 myocardial segments (in 58 patients with coronary artery disease) in which Ex-induced perfusion defects persisted in RD images. According to the changes of perfusion defects between Ex, RD and ReI images, they were classified into 3 types: Type I; perfusion defect on the RD image was identical to ReI image (75%). Type I was divided into 2 subgroups whether perfusion defect at Ex was unchanged (Ia, 42%) or improved (Ib, 33%) on the RD image. Type II; perfusion defect at Ex was reduced on the RD image and it improved furthermore at ReI image (17%). Type III; perfusion defect was the same at Ex and RD but it was reduced on the ReI image (8%). WOR less than 30% was defined as abnormal when Ex heart rate exceeded 120 bpm and lung-myocardial Tl-201 uptake ratio wasnd lung-myocardial Tl-201 uptake ratio was less than 0.45. The differentiation between Type Ia and Type III is of great importance. History of myocardial infarction, effort angina and Ex induced ST depression could not differentiate these 2 groups. WOR abnormality was observed in all of Type III, but WOR was normal in Type Ia. In conclusion, WOR abnormality in Ex-RD myocardial imaging is useful for evaluating myocardial viability. ReI imaging is necessary for the precise evaluation of viable muscle mass and for inadequate Ex. (author)

  6. Evaluation of clinical usefulness of myocardial perfusion imaging with tetrofosmin in patients with ischemic heart disease. Comparison with 201Tl SPECT

    International Nuclear Information System (INIS)

    We evaluated the clinical usefulness of 99mTc-1, 2-bis[bis(2-ethoxyethyl)phosphino]ethane (tetrofosmin) and compared it with 201Tl. The subjects consisted of 12 patients including 8 patients with old myocardial infarction (OMI), 2 with effort angina, one with stable angina and one with myocarditis. The tetrofosmin SPECT images were obtained during exercise and at rest. The quality of tetrofosmin SPECT images was equal or slightly superior to that of 201Tl. And the sensitivity, specificity and accuracy of tetrofosmin for the detection of coronary stenosis and/or obstruction were equal to that of 201Tl. We conclude that tetrofosmin is useful in the diagnosis of ischemic heart disease. (author)

  7. Nitrate administration to enhance the detection of myocardial viability by technetium-99m tetrofosmin single-photon emission tomography

    International Nuclear Information System (INIS)

    A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with 99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction 201Tl rest-injection and 99mTc-tetrofosmin baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake ?50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of 99mTc-tetrofosmin at baseline correlated with that of 201Tl (r=0.82, P 99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had 99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on 201Tl studies, but 20 segments that were non-viable on 99m99mTc-tetrofosmin studies were viable on 201Tl studies. Using a threshold value of ?40% of peak activity, only seven segments remained non-viable on 99mTc-tetrofosmin studies. Overall agreement between 99mTc-tetrofosmin with nitrates and 201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with 99mTc-tetrofosmin was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies. (orig.). With 4 figs., 3 tabs

  8. Double myocardial scintigraphy with thallium 201 (Tl) and technetium containing pyrophosphate (PYP) in acute thrombosis

    International Nuclear Information System (INIS)

    Tests were carried out with thallium 201 (Tl) and technetium containing pyrophosphate (PYP) to compare their diagnostic sensitivity and estimate their possibilities for thrombosis size determinations. The study shows that double scintigraphy (Tl+PYP) supplies information on the size of the necrosis and promises more precise quantification, an important point considering the relationship which exists between the size of a thrombosis and the clinical prospects. PYP appears more sensitive than Tl, especially for non-transmural necroses and small thromboses. The diagnostic value of PYP is greater than that of Tl during the subacute phase

  9. 123I-MIBG myocardial scintigraphy in diabetic patients. Relationship with 201Tl uptake and cardiac autonomic function

    International Nuclear Information System (INIS)

    The purpose of this paper is to investigate the influence of diabetic myocardial damage (suspected myocardial damage; SMD) diagnosed by 201Tl-SPECT and diabetic cardiac autonomic neuropathy (AN) on myocardial MIBG uptake in patients with NIDDM. Eighty-seven diabetic patients divided into four subgroups: 23 with SMD (+) AN (+); 19 with SMD (+) AN (-); 27 with SMD (-) AN (+); 18 with SMD (-) AN (-), and 10 controls were studied. Both planar and SPECT images were taken at 30 minutes (early) and 3 hours (delayed) after 123I-MIBG injection. The heart to mediastinum uptake ratio (H/M) and washout ratio of 123I-MIBG (WR) were obtained from both planar images. Similarly, the difference between the 201Tl image and the 123I-MIBG image in the total uptake score (TUS) was taken as the difference in the total uptake score (?TUS) representing cardiac sympathetic denervation without SMD. On both early and delayed planar images, the mean H/M value in the subgroups of diabetic patients was significantly lower in the SMD (+) AN (+) group than in the control group, but among those subgroups, there was statistically significant difference between the SMD (+) AN (+) and SMD (-) AN (-) groups only on the delayed images. Regarding the WR value, there was no statistically significant difference among subjects. On SPECT image analysis, the diabetic subgroup with AN or SMD had statistically significant lower values for TUS than those of tcant lower values for TUS than those of the control group. Among diabetics, there was a statistically significant differences between SMD [+] AN [+] and SMD [-] AN [-] on both early and delayed images. Similarly, the SMD [+] AN [-] group also had significantly lower values than those of SMD [-] AN [-] on early images. Regarding ?TUS, there was a statistically significant differences between AN [+] subgroups and controls. Similarly, the mean value for ?TUS was much higher in AN [+] subgroups than in AN [-] subgroups with or without SMD in diabetes mellitus. (K.H.)

  10. Evaluation of myocardial viability and efficacy of reperfusion therapy by dual-SPECT using 99mTc-PYP and 201Tl in acute myocardial infarction

    International Nuclear Information System (INIS)

    Dual SPECT using 99mTc-PYP and 201Tl was performed in 70 patients with acute myocardial infarction, and the ratio of overlap zone between 201Tl and 99mTc-PYP uptake in the infarcted area was determined (the Y-ratio). The Y-ratio was significantly higher in the group with redistribution in the infarcted area on exercise thallium myocardial scintigraphy in the chronic stage of infarction, as well as in the group with normal left ventricular wall motion. Thus, the Y-ratio value was apparently useful in the evaluation of myocardial viability. Patients from 60% of the Y-ratio upward are suggested that myocardial viability had been survived. When the Y-ratio was determined in 30 patients who underwent early reperfusion therapy (ICT or direct-PTCA), no significant difference was found between the ICT group and the direct-PTCA group. However, the Y-ratio was significantly higher when reperfusion was performed within 6 hours than when it was performed after 6 hours, and a significant positive correlation (r=0.63, p<0.01), was found between reperfusion time from cardiac event within 9 hours and the value of (100- the Y-ratio). In conclusion, the Y-ratio grateful appeared to be useful for the quantitative evaluation of myocardial viability in the acute stage of myocardial infarction. In addition, it appears to be important to perform reperfusion as soon as possible to improve myocardial salvage. (author). (author)

  11. [The "white hole" phenomenon--a potential functional parameter in non-gated 201Tl-myocardial scintigraphy].

    Science.gov (United States)

    Horn, H; Magerle, R; Clausen, M; Weller, R; Henze, E

    1993-02-01

    In 50 patients with a "white hole" in their scintigram--among them 44 patients with a history of myocardial infarction--the relation between its relative volume and the ventriculographically determined ejection fraction was studied retrospectively. A relative volume of the "white hole" larger than 13.7% showed a specificity of 93% and a sensitivity of 45% for a decreased ejection fraction and had a significant correlation of r = -0.54 (alpha = 0.01) with the ejection fraction. Thus the relative volume of the "white hole" derived automatically from 201Tl-SPECT is an easy-to-determine additional parameter which allows an at least semiquantitative statement about the function of the left ventricle. PMID:8464763

  12. The value of 201Tl myocardial scintigraphy and of computed tomography for predicting the effectiveness of coronary artery bypass surgery

    International Nuclear Information System (INIS)

    50 male patients with stenosing coronary artery sclerosis and an indication for coronary artery bypass surgery were subjected to pre- and postsurgical 201Tl scintigraphy and postsurgical computed tomography. Control by angiography was carried out in six cases. Scintigraphy revealed an improved myocardial perfusion in 30 patients, whereas it was unchanged in 15 and deteriorated in 5 patients. Angiography exhibited two cases of graft occlusion, one case of bad run off, and two cases of progressing arteriosclerosis under intact graft. Computed tomography showed that 83 bypasses of the 50 patients were occluded in 6 cases, which was confirmed by angiography in 3 cases. The investigation demonstrates the high value of the two non-invasive methods for the control of bypass patency. (author)

  13. Evaluation of simultaneous 99mTc-MIBI and 201Tl dual-isotopic myocardial perfusion SPECT imaging for the detection of the hibernating myocardium

    International Nuclear Information System (INIS)

    Objective; To study the clinical role of rest technetium-99m sestamibi (99mTc-MIBI) and stress-reinjection thallium-201 (201Tl) simultaneous dual-isotopic myocardial perfusion SPECT imaging in the detection of the 'hibernating myocardium'. Methods: 77 patients with suspected coronary artery disease underwent simultaneous dual-isotopic myocardial perfusion SPECT imaging with 99mTc-MIBI and 201Tl. 18mCi (666 MBq) 99mTc-MIBI was injected at rest, 15 min later dobutamine was instilled into vein begin with 5 mg·kg-1 min-1, before and after instilling the base ECG, blood pressure, heart rate was recorded, when the end point were reached, 3mCi (111 MBq) thallium-201 was injected, the early dual-isotopic simultaneously SPECT imagine was performed. After tomographic reconstruction, the defect were found on the stress 201Tl and rest 99mTc-MIBI image, 3 hr later 1mCi (37 MBq) thallium-201 was reinjected. 30 min later after that the delay dual-isotopic simultaneously SPECT imagine was performed. The images were interpreted by two experienced observers without previous knowledge of results of other studies. In two weeks, coronary angiography was performed. Results: (1) All of 77 patient were found abnormal by angiography, 39 of those with one coronary artery abnormality, 27 with two coronary artery abnormality, 11 with three coronary artery abnormality. (2) 23 with the radioactivity defect on the stress 201Tl and rest 99mTc-M stress 201Tl and rest 99mTc-MIBI image showed radiofilling on the reinjection images, therefore 'hibernating myocardium' was suggested. (3) 54 with the radioactivity defect on the stress 201Tl and rest 99mTc-MIBI image didn't show radiofilling on the reinjection images, thus infarct myocardium or scar issue was suggested. Conclusion: Simultaneous rest 99mTc-MIBI and stress-reinjection 201Tl Dual-isotopic myocardial perfusion SPECT imaging is an effective method in the detection of the hibernating myocardium. (authors)

  14. Assessment of infarct volume in acute myocardial infarction using 99mTc-pyrophosphate SPECT. Comparison with 201Tl defect, CPK and LVEF

    International Nuclear Information System (INIS)

    We measured infarct size (volume) in 15 patients with acute myocardial infarction (AMI) using 99mTc-pyrophosphate and single photon emission computed tomography (SPECT) (PYP-SPECT). PYP-SPECT was performed between the 2nd and 6th days after the onset of AMI. The infarct size (PYP infarct size) was calculated by summing up the pixels with counts over a certain cut-off level in the transaxial and short axial images obtained by PYP-SPECT, and was compared with the relative infarct size obtained by 201Tl myocardial SPECT (%Tl infarct size), peak CPK, ?CPK and left ventricular ejection fraction (LVEF) measured by 99mTc blood pool study. In addition to the measurement of the PYP infarct size, we calculated the relative infarct size (%PYP infarct size) from the defect length in the long axial image and the defect angle in the short axial image. Both the transaxial and short axial images were almost equally useful for the measurement of the PYP infarct size. The PYP infarct size and %PYP infarct size correlated well with %Tl infarct size (r = 0.7 - 0.8 and r=0.953, respectively). They also correlated with peak CPK (r = 0.6 - 0.65) and ?CPK (r = 0.8 - O.9). However. there was not a good correlation between the PYP infarct size and LVEF (r = -0.4 - -0.5). We conclude that PYP-SPECT is a very useful and reliable procedure that can delineate infarct size in AMI patients. (author)

  15. A comparison of rest sestamibi and rest-redistribution thallium single photon emission tomography: Possible implications for myocardial viability detection in infarcted patients

    International Nuclear Information System (INIS)

    Thirty patients (26 men, 4 women, mean age 61±8 years) who had suffered myocardial infarction 15±6 months previously, were submitted to (1) standard stress-redistribution thallium-201 single photon emission tomography (SPET), (2) rest-redistribution 201Tl SPET and (3) stress-rest technetium-99m sestamibi SPET. Uptake modifications in relation to exercise-induced defects were evaluated in a total of 390 myocardial segments. Tracer uptake was scored as normal (=0), mildly reduced (=1), apparently reduced (=2), severely reduced (=3) or absent (=4). Comparison of stress studies failed to show any statistical difference (58% segmental abnormalities with sestamibi vs 61% with thallium). Uptake abnormalities (score 1-4) were detected in 55% of the segments with rest sestamibi, 55% with standard thallium redistribution, 55% with early imaging after thallium injection at rest and 54% with 3-h delayed rest imaging (P=NS). Absence of tracer uptake (score=4) under resting conditions was recorded in 75 (19%) segments with standard 201Tl redistribution, 75 (19%) with rest sestamibi, 70 (18%) with rest 201Tl imaging and 62 (16%) with rest-redistribution 201Tl (P<0.05 vs other imaging modalities). Thus, 3-h delayed rest thallium imaging detected reversibility of uptake defects in a significantly higher number of myocardial segments. This finding might have important implications for both tracer and technique selection when myocardial viabtechnique selection when myocardial viability is the main clinical issue. (orig.)

  16. Prediction of cardiac events in patients with dilated cardiomyopathy using 123I-BMIPP and 201Tl myocardial scintigraphy

    International Nuclear Information System (INIS)

    Various clinical trials for dilated cardiomyopathy (DCM) have demonstrated that the prognosis as well as cardiac function is improved by the administration of beta-blocker therapy. On the other hand, 123I-betamethyl-p-iodophenyl-pentadecanoic acid (BMIPP) reflects myocardial fatty acid metabolism and is considered to be a more sensitive tracer than perfusion tracers. In this study, the efficacy of DCM for the evaluation of myocardial damage and the prediction of cardiac events was studied using 123I-BMIPP and 201Tl (Tl) myocardial scintigraphy. Study subjects comprised 33 DCM patients, divided into a cardiac event group (event, n=9) and an event-free group (event free, n=24). An extent score (ES) and severity score (SS) were calculated for each BMIPP image. BMIPP and Tl images were divided into 17 segments, and total defect scores (TDS) were calculated for each. The TDS of the BMIPP and Tl images were compared with score differences greater than or equal to 4 and less than 4 defined as mismatch and non-mismatch, respectively. The TDS of BMIPP was significantly higher in the event group than in the event-free group (P2 test; P<0.01). The ES of BMIPP was a significant predictor of caf BMIPP was a significant predictor of cardiac events in the multivariate analysis (P<0.01). These results suggest that the ES for BMIPP is useful as a predictor of cardiac events in DCM. (author)

  17. Septal Q wave disappearance in V6 lead and myocardial damage comparison of 12-lead electrocardiography and 201Tl myocardial SPECT

    International Nuclear Information System (INIS)

    Septal Q wave disappearance in V6 has been thought to signify myocardial septal damage. In this study, to verify significance of septal Q wave disappearance in V6 in cases with anteroseptal myocardial damage, we compared ECG and 201Tl SPECT findings. The subject were 107 patients (80 males, 27 females, mean age 58.2±10.1 years) who took exercise 201Tl SPECT because of suspicious of ischemic heart disease. The patients were divided into two groups. One was the patients with septal Q (septal Q (+) group) and the other was the patients without septal Q (septal Q (-) group). The definition of septal Q wave disappearance was that it was smaller than 0.025 mV. The patients with abnormal Q in V6 were excluded. A SPECT image was divided into 13 segments. Tl uptake scores were classified into 4 levels by visual evaluation at the each segments. Septal Q (-) group had a significantly higher rate of anteroseptal infarction than septal Q (+) group (p=0.01), and showed a significantly higher defect in anteroseptal area (p6 may be one of parameters which assume anteroseptal myocardial damage. (author)

  18. A new protocol of dual energy acquisition on stress 201Tl and rest 99mTc-tetrofosmin myocardial scintigraphy

    International Nuclear Information System (INIS)

    We carried out stress 201Tl (Tl) and rest 99mTc-tetrofosmin (TF) myocardial scintigraphy with dual energy acquisition in 24 patients with suspected ischemic heart disease performed coronary arteriography and elucidated the sensitivity of this method. One hour after light meal eating, TF (555 MBq) was injected intravenously at rest and after 3 minutes from injection of TF exercise or pharmacologic stress was performed. During stress Tl (111 MBq) was injected intravenously before end-point or at adequate point of pharmacologic stress. Dual energy acquisition using triple energy windows (TEW) was started after 5 minutes (early) and 4 hours (delayed) from stress. The sensitivity (Sn), specificity (Sp) and accuracy (Ac) in diagnosis of non-infarcted branches by using Tl (early)-TF (rest) and Tl (early)-Tl (delayed) were 79% vs. 53% (Sn), 78% vs. 96% (Sp) and 79% vs. 71% (Ac) respectively. Accordance of uptake score of infarcted region between TF (rest) and Tl (delayed) was 70%. In conclusion, this protocol is seemed to be useful as usual protocol for detection of myocardial ischemia and viability during about only 1 hour. (author)

  19. [Clinical usefulness of 201Tl/99mTc-PYP dual myocardial quantitative gated SPECT program using low-dose dobutamine loading in assessment of myocardial viability in patient with acute myocardial infarction--a case report].

    Science.gov (United States)

    Irie, Hidekazu; Ito, Kazuki; Koide, Masahiro; Taniguchi, Takuya; Yokoi, Hirokazu; Nakamura, Reo; Kinoshita, Noriyuki; Hashimoto, Tetsuo; Tamaki, Shunichi; Sawada, Takahisa; Azuma, Akihiro; Matsubara, Hiroaki

    2006-05-01

    An 86-year-old man with chest pain was admitted to our hospital. Coronary angiography revealed 99% stenosis of the mid segment of the left anterior descending coronary artery, therefore, a coronary stent was implanted. Immediately after the stent implantation, 99% stenosis occurred at the proximal site of the 1st diagonal artery because of stent jeal. On the 4th hospital day, ECG-gated 201TL/99mTc-PYP dual myocardial quantitative gated SPECT was performed at rest and during low-dose dobutamine loading. The 201Tl scintigraphy revealed moderately reduced uptake in the anterior, septal and apical walls, and 99mTc-PYP uptake was observed in the mid-anterior wall. A three-dimensional surface display of gated 201Tl SPECT images showed severe hypokinesis in the anterior, septal and apical walls at rest. On the other hand, during low-dose dobutamine loading, improved wall motion was observed in the basal anterior and septal walls, while no change was observed in the midanterior and apical wall movements. Three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images revealed similar patterns of wall motion as those of gated 201Tl SPECT images at rest. During low-dose dobutamine loading, on the other hand, a three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images revealed improved wall motion in the basal anterior, septal and apical walls, but worsened wall motion of the mid-anterior wall. After 6 months, a follow-up coronary angiography revealed no re-stenosis of the stent, but 99% stenosis at the proximal aspect of the 1st diagonal artery. Left ventriculography revealed improved wall motion in the apex and akinesis of the mid-anterior wall. These wall motion findings were similar to those visualized in the three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images during low-dose dobutamine loading in the acute phase. These results suggest that 201Tl/99mTc-PYP dual myocardial quantitative gated SPECT using low-dose dobutamine loading could be useful for the assessment of myocardial viability after reperfusion therapy in patients with acute myocardial infarction. PMID:16838664

  20. Double-nuclide study of the myocardium using 201Tl and 123I-labeled fatty acids in non-ischemic myocardial diseases

    International Nuclear Information System (INIS)

    Metabolic impairment and perfusion abnormalities are known to occur in hypertensive heart disease (HHD) and in cardiomyopathies. Free fatty acid (FFA) extraction is severely inhibited in a number of pathobiochemical reactions. This parameter was assessed using the radiolabeled FFA analogue 123I-(p-iodo-phenyl-)-pentadecanoic acid (IPPA) and 201Tl as perfusion marker, both of them injected at maximal physical workload. The regional extraction fraction of IPPA (IPPA-EF) was estimated by relating the regional IPPA and 201Tl uptake to each other. In HHD (normal coronary arteries) with posterior wall thickness ?12 mm IPPA-EF was 77 ± 18% (SD) in septum and 92 ± 17% in the posterolateral wall (N = 13), with thickness of >12 mm 60 ± 23% in septum and 61 ± 20% in the posterolateral wall (N = 8) when compared with IPPA-EF in normal subjects (= 100%, N = 9). In hypertrophic cardiomyopathy (HCM) IPPA-EF averaged 51 ± 20% in septum and 87 ± 10% in the posterolateral wall (N = 11). In these patient groups no systematic regional changes in 201Tl uptake were observed. In dilated cardiomyopathy (DCM) both IPPA-EF and 201Tl uptake showed distinct regional variations and a great interindividual variability with a mean IPPA-EF reduction of 12% (N = 9). Thus, IPPA uptake in primarily non-ischemic myocardial disease may already be compromised when 201Tl uptake is unchanged. The double-nuclide method for IPPA-EF detele-nuclide method for IPPA-EF determination allows to eliminate the influence of flow in FFA imaging and enhances the potential of scintigraphy in the differential diagnosis of HHD versus coronary artery disease. (orig.)

  1. Comparison study of left ventricular ejection fraction measured by 201Tl gated myocardial imaging and 99mTc-red blood cell gated blood-pool imaging

    International Nuclear Information System (INIS)

    Objective: To explore the correlation of automatic quantification of left ventricular ejection fraction (LVEF) from gated myocardial perfusion SPECT with 201Tl and rest equilibrium gated blood- pool imaging with 99mTc-red blood cell. Methods: Rest gated myocardial perfusion SPECT with 201Tl was performed on 72 cases. AUTOQUANT 4.21 software was used to measure LVEF. Rest equilibrium gated blood-pool imaging was also performed within 24 h. The values of LVEF measured by two methods were calculated and compared. Results: (1)There were strong correlation between the LVEF measured by rest gated myocardial perfusion SPECT and rest equilibrium gated blood-pool imaging(r=0.554, P=0.000). There was no significant difference between the two methods (t=1.194, P>0.05). (2) There was no significant difference between the two methods among different disease groups. (3) The values of LVEF measured by two methods were (64.68 ± 10.77)% and (62.46±8.99)%. The values of LVEF measured by gated myocardial perfusion SPECT was higher 3.55% than rest equilibrium gated blood-pool imaging. Conclusion: There was good correlation between the LVEF measured with gated myocardial perfusion SPECT by AUTOQUANT 4.21 software and gated blood-pool imaging. The LVEF can be accurately evaluated using gated myocardial perfusion SPECT with 201Tl. The value of LVEF measured by gated myocardial perfusion SPECT was higher than rest equilibrium gated blood-pool imaan rest equilibrium gated blood-pool imaging. (authors)

  2. Assessment of myocardial perfusion and cardiac sympathetic nerve dysfunction in patients with sick sinus syndrome. Evaluation of coronary hemodynamics and 201TlCl/123I-MIBG myocardial SPECT

    International Nuclear Information System (INIS)

    To clarify the coronary hemodynamics, myocardial perfusion and cardiac sympathetic nerve function in patients with sick sinus syndrome (SSS), we performed left coronary digital subtraction angiography (DSA) in 41 patients, exercise 201TlCl-myocardial scintigraphy (planar and SPECT) in 69 patients, and 201TlCl/123I-MIBG myocardial dual SPECT in 13 patients without significant organic coronary stenosis. Coronary artery spasm was documented on coronary angiography in 25/43 (58%) patients with SSS by ergonovine provocation test. Compared with normals, patients with SSS demonstrated prolongation of left coronary circulation time (CCT) on own heart beats and right atrial pacing. We suspected that prolonged CCT may be induced by increased peripheral coronary vascular resistance and impaired coronary micro-circulation in patients with SSS. Forty-two patients (60.9%) developed exercise-induced 201Tl-myocardial perfusion defect on SPECT images. On myocardial dual SPECT images, 11/13 (85%) patients showed localized myocardial low uptake in 123I-MIBG-SPECT images. In eight patients with normal findings on 201Tl-SPECT, six patients showed abnormality on 123I-MIBG-SPECT. We suspected that coronary vasospasm, impaired coronary micro-circulation and cardiac sympathetic nerve dysfunction are taken a part of pathophysiology in SSS (decreased ?-adrenergic receptor of peripheral coronary arteries?). (author)ripheral coronary arteries?). (author)

  3. Estimation of systemic lysis of acute myocardial infarct by radionuclide ventriculography and by 201Tl myocardial scintigraphy using also emission computed tomography

    International Nuclear Information System (INIS)

    First experiences with fibrinolysis treatment by continuous streptokinase infusion for reopening of coronary arteries closed by thrombus in 28 patients with acute myocardial infarct are reported. The success of treatment is proved by means of the 201Tl myocardial scintigraphy as well as by ventriculoscintigraphy with /sup 99m/Tc-erythrocytes after homogeneous distribution of activity. In ventriculoscintigraphy both quantitative parameters (ejection fraction, maximum filling and evacuation rate) and wall motility disturbances of the left ventricle are proved. Similar results are gained with both the noninvasive methods completing each other. The therapeutic effect of the systemic lysis was statistically significant in the infarction of the anterior wall but not in that of the posterior wall. (author)

  4. Differential diagnosis of idiopathic congestive cardiomyopathy and ischemic heart disease by echocardiography and 201Tl-myocardial scintigraphy

    International Nuclear Information System (INIS)

    The usefulness of various non-invasive methods such as electrocardiography, echocardiography and 201Tl myocardial scintigraphy in the differential diagnosis of idiopathic congestive cardiomyopathy (CCM) and ischemic heart disease (IHD) were evaluated. Eighteen cases with CCM and 9 cases with IHD were subjected. For this study patients with IHD showing dilated cavity (LVDd over 66 mm) and diffuse hypokinesis of the left ventricle in the echocardiogram were selected. Cardiothoracic ratio of CCM and IHD were 59.6 +- 6.3% and 58.3 +- 6.3% in average, respectively. In CCM, mean LVDd was 76.0 +- 5.6 mm and mean LVDs was 63.4 +- 7.3 mm. In IHD, mean LVDd was 74.7 +- 8.1 mm and mean LVds was 63.2 +- 4.6 mm. Both cardiothoracic ratios and echocardiographic findings showed no difference between CCM and IHD. Incidence of an abnormal Q wave in ECG was higher in IHD (2.72 leads per a case) than that in CCM (1.33 leads per a case). An abnormal Q wave in aVL was frequently (28%) observed in CCM but none in IHD. However, these ECG findings did not seem to be contributory to the differential diagnosis. Myocardial scintigraphic study revealed that 10 of 18 cases with CCM showed no perfusion defect or sparse uptake and others showed small and isolated defect in the apex or postero-lateral wall of the left ventricle, while 7 of 9 cases with IHD showed large perfusion defect over 15% in the anterior and inferior areas. However, small localized defects less than 14% in the apex calized defects less than 14% in the apex were observed in both groups, 5 cases (27.8%) with CCM, and 2 cases (22.2%) with IHD, suggesting limitation of this method for the differential diagnosis. (J.P.N.)

  5. Clinical investigation of large perfusion defect cases with 201Tl exercise myocardial scintigraphy

    International Nuclear Information System (INIS)

    We investigated retrospectively the clinical significance of large perfusion defect on 201Thallium myocardial scintigraphy from the records of 833 patients during the past 3 years from 1991 to 1994. The patients were divided into 3 groups according to the extent of perfusion defect; cases with normal perfusion (n=561), with small perfusion defect (n=211) and with large perfusion defect (n=61). We found that the proportions of cases with large perfusion defect was significantly larger than that of cases with small perfusion defect in myocardial disease (MD; hypertrophic cardiomyopathy, dilated cardiomyopathy, and post myocarditis combined) (P201Thallium myocardial scintigraphy and that complication of diabetes mellitus and clinical symptoms may be useful in differentiating IHD from MD. (author)

  6. Quantitative analysis of exercise 201Tl myocardial emission CT in patients with coronary artery disease

    International Nuclear Information System (INIS)

    The clinical usefulness of quantitative analysis of exercise thallium-201 myocardial emission computed tomography (ECT) was evaluated in coronary artery disease (CAD). The subjects consisted of 20 CAD patients and five normal controls. All CAD patients underwent coronary angiography. Tomographic thallium-201 myocardial imaging was performed with a rotating gamma camera, and long-axial and short-axial myocardial images of the left ventricle were reconstructed. The tomographic images were interpreted quantitatively using circumferential profile analysis. Based on features of regional myocardial thallium-201 kinetics, two types of abnormalities were studied: (1) diminished initial distribution (stress defect) and (2) slow washout of thallium-201, as evidenced by patients' initial thallium-201 uptake and 3-hour washout rate profiles which fell below the normal limits, respectively. Two diagnostic criteria including the stress defect and a combination of the stress defect and slow washout were used to detect coronary artery lesions of significance (>=75 % luminal narrowing). The ischemic volumes were also evaluated by quantitative analysis using thallium-201 ECT. The diagnostic accuracy of the stress defect criterion was 95 % for left anterior descending, 90 % for right, and 70 % for left circumflex coronary artery lesions. The combined criteria of the stress defect and slow washout increased detection sensitivity with a moderate loss of specificity for identifying individoss of specificity for identifying individual coronary artery lesion. A relatively high diagnostic accuracy was obtained using the stress defect criterion for multiple vessel disease (75 %). Ischemic myocardial volume was significantly larger in triple vessel than in single vessel disease (p < 0.05) using the combined criteria. It was concluded that quantitative analysis of exercise thallium-201 myocardial ECT images proves useful for evaluating coronary artery lesions. (author)

  7. Clinical investigation of large perfusion defect cases with {sup 201}Tl exercise myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Morota, Motoi; Kobayashi, Yasuhiko [Tokyo Medical Coll. (Japan)

    1999-02-01

    We investigated retrospectively the clinical significance of large perfusion defect on {sup 201}Thallium myocardial scintigraphy from the records of 833 patients during the past 3 years from 1991 to 1994. The patients were divided into 3 groups according to the extent of perfusion defect; cases with normal perfusion (n=561), with small perfusion defect (n=211) and with large perfusion defect (n=61). We found that the proportions of cases with large perfusion defect was significantly larger than that of cases with small perfusion defect in myocardial disease (MD; hypertrophic cardiomyopathy, dilated cardiomyopathy, and post myocarditis combined) (P<0.001). Analyzing patients with ischemic heart disease (IHD; angina pectoris and myocardial infarction) according to the severity of coronary artery lesion, the proportion of cases with large perfusion defect was significantly larger than that of cases with small perfusion defect in 3 vessel disease (P<0.001). Incidence of diabetes mellitus was significantly higher in patients with IHD than in those with MD in large perfusion defect group (P<0.01). As for symptoms in large perfusion defect group, the incidences of chest pain, chest oppression, and chest discomfort were significantly higher in patients with IHD than in those with MD (P<0.001), whereas the incidences of palpitation and shortness of breath were significantly higher in patients with MD (P<0.001). These results suggest that IHD with multiple artery lesions and MD underlie large perfusion defect on {sup 201}Thallium myocardial scintigraphy and that complication of diabetes mellitus and clinical symptoms may be useful in differentiating IHD from MD. (author)

  8. Detection of myocardial viability by delayed imaging after 201Tl reinjection

    International Nuclear Information System (INIS)

    Recent studies have demonstrated that some underestimation of myocardial viability remained to be not resolved even using reinjection method. So we devised a new technique of reinjection and reimaging, and using this we studied the detectability of myocardial viability in 32 patients of CAD. Exercise imaging (EX) was acquired after initial injection of thallium (111 MBq). Three hours after EX, the second dose thallium (37 MBq) was reinjected, and then the first reinjection image (Re1) was performed. Furthermore, the second reinjection image (Re2) was obtained at 3 hours after the second dose reinjection. SPECT images were divided into basal, mid and apical parts, and totally 13 segments were analyzed by visual scoring (0: severe, 1: moderate, 2: mild hypoperfusion and 3: normal). Twenty-seven (13.4%) of 202 segments of low score (0 to 2) shown in EX were improved in Re2, compared with Re1. Twenty-one (42.0%) of 50 segments of score 0 or 1 shown in Re1 were improved in Re2. These results showed that our devised new method of reimaging 3 hours after the second dose injection was useful to improve in detectability of myocardial viability. (author)

  9. The quantitative evaluation of 201Tl myocardial scintigraphy using reinjection method

    International Nuclear Information System (INIS)

    This study was designed to determine whether Tl-201 myocardial scintigraphy using reinjection method would improve the rate of redistribution (RD) and, if improved, which would contribute to RD improvement, extent or severity of ischemia shown by the bolls-eye view method. In 17 patients with ischemic heart disease, exercise Tl-201 myocardial images were acquired at 10 min (early images) and 180 min (delayed images) after intravenous injection of 74 MBq of TlCl. In addition, 37 MBq of TlCl was injected again after delayed imaging and then images were acquired (RI images). Among the 17 patients, 7 were judged as RD(+), 8 as RD(-), and 2 as undefined. In 8 RD(-) patients and 2 undefined patients, RD became (+) on RI images. Visual changes in extent and severity of ischemia from early to delayed images were 68±42 for RD(+) cases vs. 3±20 for RD(-) cases and 0.4±0.8 for RD(+) cases vs. 0.1±0.3 for RD(-) cases, respectively. The corresponding figures from delayed to RI images for extent and score of ischemia were 50±46 for RD(+) cases vs. 13±22 for RD(-) cases and 0.4±30.3 for RD(+) cases vs. 0.1±0.5 for RD(-) cases, respectively. For 5 patients undergoing coronary revascularization, extent was improved in all cases, but severity was improved in only some cases. In conclusion, when RD became (+) on RI images, myocardial viability seemed to have been underestimated. Quantitative evaluation revealed that RD improved from early to delayed images depended on extent andayed images depended on extent and that RD improved from delayed to RI images depended on both extent and severity. In postoperative improvement of RD, extent of ischemia was mainly involved. RI imaging was found to compensate for the underestimation of RD. Quantitative evaluation was also useful in the observation of subtle changes of ischemia. (N.K.)

  10. Results of RNV studies and 201Tl myocardial scintigraphy in patients with progressive systemic scleroderma (PSS)

    International Nuclear Information System (INIS)

    Prognosis of progressive systemic scleroderma (PSS) depends directly on the extent of visceral organ involvement, and in particular, on the cardiac, renal and pulmonary appearance. Therapeutic approaches therefore require periodic followup with non-invasive methods to evaluate the actual course of disease and the success of therapy. Tl-201 scintigraphy showed pathologic heart abnormalities in 47% and RNV in 23% of the PSS patients. Our results and published data reveal the sensitivity of both myocardial scans and RNV in the evaluation of patients with PSS. Other current methods for the diagnosis of heart diseases, however, such as echocardiography should also be performed. In patients with PSS coronary angiography, however, usually shows normal coronary vessels. (orig.)

  11. Importance of 201Tl scintigraphy during exercise for diagnosis of silent myocardial ischemia

    International Nuclear Information System (INIS)

    Using thallium scintigraphy during exercise (TSE), suspect silent myocardial ischemia (SIM) was diagnosed in subjects without angina pectoris. 21 active pilots with suspect SIM were examined after previous exercise ECG as well as 33 patients with diabetes type I and II. In six pilots (28.6%) TSE showed accumulation defects suggesting ischemic disorders of the large coronary arteries. Five pilots showed obvious depressions of the ST segment in ECG during submaximal exercise TSE. In another group of five pilots small depressions of the ST segment were associated with normal TSE. Twelve diabetic patients (36.4%) had minor accumulation defects on TSE. Only two showed a ST depression under 2 mm in ECG during TSE. Based on data in the literature suggesting higher sensitivity and specificity of exercise thallium scintigraphy as compared with exercise ECG and the possibility of a false positive diagnosis of SIM from exercise ECG alone, it is recommended to also use TSE. A more detailed diagnosis of SIM is essential not only with regard to the assessment of work capacity but also for a long-term follow-up of patients with SIM for assessment of its incidence, impact and prognosis in the population. (author). 4 figs., 4 tabs., 25 refs

  12. Dobutamine stress thallium-201 single-photon emission tomography versus echocardiography for evaluation of the extent and location of coronary artery disease late after myocardial infarction

    International Nuclear Information System (INIS)

    Dobutamine stress echocardiography and thallium-201 myocardial perfusion scintigraphy are clinically useful methods for the evaluation of coronary artery disease (CAD). However, the relative merits of these imaging modalities in the evaluation of the extent of CAD after myocardial infarction have not been well studied. The aim of this study was to compare the accuracy of dobutamine stress echocardiography and simultaneous 201Tl single-photon emission tomography (SPET) imaging for the diagnosis and localization of CAD late after acute myocardial infarction. Dobutamine (up to 40 ?g kg-1 min-1)-atropine (up to 1 mg) stress echocardiography in conjunction with stress-reinjection 201Tl SPET was performed for the evaluation of myocardial ischaemia in 90 patients with previous myocardial infarction who underwent coronary angiography. Significant CAD was predicted on bases of myocardial ischemia (new or worsening wall motion abnormalities on echocardiography and reversible perfusion defects on 201Tl SPET). Significant CAD (? 50% luminal diameter stenosis) was detected in 73 (81%) patients. The sensitivity, specificity and accuracy of echocardiography in detecting remote ischaemia for the diagnosis of remote CAD (present in 53 patients) were, respectively, 79% (CI 70%-88%), 85% (CI 77%-93%) and 81% (CI 73%-90%), while the corresponding figures for 201Tl SPET were 75% (CI 66%-85%), 78% (CI 69%-87%) and 76% (CI 66%-85%), 78% (CI 69%-87%) and 76% (CI 67%-86%) respectively (P = NS vs echocardiography). The sensitivity, specificity and accuracy of echocardiography in detecting peri-infarction ischaemia for the diagnosis of infarct-related artery stenosis (present in 70 patients) were, rspectively, 77% (CI 68%-86%), 85% (CI 78%-92%) and 79% (CI 70%-87%) while the corresponding figures for 201Tl SPET were 73% (CI 64%-82%), 85% (CI 78%-92%) and 76% (CI 67%-84%) respectively (P = NS vs echocardiography). The agreement between the two methods for the diagnosis of peri-infarction and remote ischaemia was 70% (kappa = 0.37) and 80% (kappa = 0.59) respectively. It is concluded that dobutamine stress echocardiography and 201Tl SPET have comparable accuracy for the diagnosis of infarct related and remote CAD in patients with previous myocardial infarction. The agreement between the methods is higher for the diagnosis of remote CAD than for that of peri-infarction ischaemia. (orig.)

  13. Effect of long-term cholesterol-lowering treatment with HMG-CoA reductase inhibitor (Simvastatin) of myocardial perfusion evaluated by thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    Fifteen patients with either angina pectoris or old myocardial infarction, who had positive 201Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n=25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on 201Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on 201Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on 201Tl SPECT images. (author)

  14. Effect of long-term cholesterol-lowering treatment with HMG-CoA reductase inhibitor (Simvastatin) of myocardial perfusion evaluated by thallium-201 single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hosokawa, Ryohei; Nohara, Ryuji; Linxue, Li; Sasayama, Shigetake [Kyoto Univ. (Japan). Graduate School of Medicine; Tamaki, Shunichi; Hashimoto, Tetsuo; Tanaka, Masahiro; Miki, Shinji

    2000-03-01

    Fifteen patients with either angina pectoris or old myocardial infarction, who had positive {sup 201}Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n=25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on {sup 201}Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on {sup 201}Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on {sup 201}Tl SPECT images. (author)

  15. Role of ultrashort-lived radionuclides in cardiovascular studies: /sup 195m/Au ventriculography and simultaneous 201Tl myocardial imaging

    International Nuclear Information System (INIS)

    The advantages of ultrashort-lived radionuclides (USRN's) are multiple: (1) bedside production, (2) reduction of patient radiation exposure, (3) possibility of administering larger doses of radionuclides, (4) multiple, rapid, sequential, background-free studies, and (5) multiple, simultaneous radionuclide administrations. Simultaneous injection of thallium-201 and gold-195m at maximal exercise and at rest in 24 patients with coronary artery disease (CAD) are described. A bolus of approximately 20 mCi of /sup 195m/Au was followed 1 or 2 sec later by 2 mCi of thallium-201. During the first 25 sec, imaging of first-pass ventriculography was performed in the 260-keV window. Five minutes later /sup 195m/Au had decayed, and conventional planar imaging of 201Tl was performed. Sensitivity for diagnosis of CAD in stress first-pass radionuclide ventriculography was 83%, of wall motion 79%, and 201Tl stress myocardial perfusion was 83%. It was concluded that first-pass ventriculography and simultaneous myocardial perfusion determinations (1) are feasible procedures and (2) appear to offer the possibility of a high-sensitivity and high-specificity test for coronary artery disease

  16. Exercise and rest myocardial scintigraphy with 201TlCl/99mTc-MIBI dual energy acquisition using triple-energy window scatter correction

    International Nuclear Information System (INIS)

    We carried out dual 201Tl/99mTc-MIBI imaging to reduce the time required for exercise myocardial scintigraphy. We investigated 4 different protocols. In protocol (A), Tl was injected at rest followed by the injection of MIBI at peak exercise. Dual SPECT images were obtained by 201Tl/99mTc simultaneous acquisition. Protocol (B) means reverse either, in which MIBI was injected at rest followed by the administration of Tl at peak exercise. In protocol (C), exercise was performed first with MIBI-injection, and then Tl was injected at rest one hour later. Simultaneous acquisition was also performed. In protocol (D), after the rest Tl-imaging, MIBI was injected at peak exercise, and then the MIBI-imaging was done. In protocol (A), (B) and (C), simultaneous acquisition was performed using TEW (Triple-Energy Window) scatter correction. Thanks to using dual isotopes, all procedures could be completed within 1-2 hours, which was much shorter than the conventional myocardial perfusion imaging. Scatter correction was useful for accurate diagnoses, when the simultaneous imaging is performed. (author)

  17. Clinical studies on thallium-201 myocardial single-photon emission computed tomography in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    In order to evaluate briefly the relative 3-dimensional distribution of 201Tl in the myocardium, a 2-dimensional polar map was developed from short axis tomograms of single-photon emission computed tomography (SPECT) using circumferential profile analysis. The data collected from 180 deg rotational scan around a body were used in clinical study to acquire the projection data in a short time, although, with a heart phantom study, there was more uniformity with the 360 deg collection than with 180 deg collection. So, the polar map of relative distribution and % washout rate (% WR) were created from 180 deg data collection. To detect ischemic area, the lower limit (M-SD) of the profile curve in 10 normal subjects was processed and compared with that of patients. Then, abnormal 201Tl distribution and % WR were identified comparing each patient's profile with the corresponding normal lower limits. In 24 patients with myocardial infarction, defect score (DS), estimated as infarcted size from the relative polar map, was compared with the size of abnormal wall motion in left ventriculography. There was a good correlation (r = 0.834) between them. Also, there were close correlations between DS and regional contraction (r = -0.869), and between DS and left ventricular ejection fraction (r = -0.775) respectively. In 24 patients with non-MI angina pectoris, the diagnostic sensitivity of exercise induced ischemia was 65 % and accuracy was 76 % by relative dis65 % and accuracy was 76 % by relative distribution map. However, the sensitivity of % WR map was superior (84 %) to that of relative map, especially in the patients with mild ischemia and multi-vessel disease. In conclusion, this comprehensive polar map method represented well a 3-dimensional myocardial distribution of 201Tl. The clinical usefulness in determination of infarct size and in diagnosis of myocardial ischemia were evaluated. (author)

  18. Impaired coronary flow reserve is the most important marker of viable myocardium in the myocardial segment-based analysis of dual-isotope gated myocardial perfusion single-photon emission computed tomography

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the most robust predictor of myocardial viability among stress/rest reversibility (coronary flow reserve [CFR] impairment), 201Tl perfusion status at rest, 201Tl 24 hours redistribution and systolic wall thickening of 99mTc-methoxyisobutylisonitrile using a dual isotope gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with coronary artery disease (CAD) who were re-vascularized with a coronary artery bypass graft (CABG) surgery. A total of 39 patients with CAD was enrolled (34 men and 5 women), aged between 36 and 72 years (mean 58 ± 8 standard in years) who underwent both pre- and 3 months post-CABG myocardial SPECT. We analyzed 17 myocardial segments per patient. Perfusion status and wall motion were semi-quantitatively evaluated using a 4-point grading system. Viable myocardium was defined as dysfunctional myocardium which showed wall motion improvement after CABG. The left ventricular ejection fraction (LVEF) significantly increased from 37.8 ± 9.0% to 45.5 ± 12.3% (p 201Tl rest perfusion status (p = 0.024) were significant predictors of wall motion improvement. However, in multiple logistic regression analysis, stress/rest reversibility alone was a significant predictor for post-CABG wall motion improvement (p < 0.001). Stress/rest reversibility (impaired CFR) during dual-isotope gated myocardial perfusion SPECT was the single most important predictor of wall motion improvement after CABG.

  19. Comparison of thallium-201 single-photon emission tomography after rest injection and fluorodeoxyglucose positron emission tomography for assessment of myocardial viability in patients with chronic coronary artery disease

    International Nuclear Information System (INIS)

    This prospective study in 42 patients with chronic coronary artery disease and severe wall motion abnormalities (sWMA) on cineventriculography (24 patients with previous myocardial infarction; ejection fraction, 45%±13%) was designed to compare myocardial thallium-201 uptake after rest injection and normalized fluorodeoxyglucose (18FDG) uptake (after oral glucose load) for assessment of a rest 201Tl protocol to evaluate myocardial viability. The left ventricle was divided into the supply territory of the left anterior descending coronary artery (LAD) and the lateral wall and posterior territory (inferior, posterior and posteroseptal segments) because of the high variability of left circumflex and right coronary artery supply territories. Segmental 201Tl uptake in single-photon emission tomography (SPET) and segmental normalized 18FDG uptake (13 segments per patient) showed a close linear relationship in the LAD territory and in the lateral wall, while the correlation in the posterior territory was considerably lower. 201Tl/18FDG concordance was defined as an 18FDG uptake exceeding 201Tl uptake by 18FDG exceeded 201Tl uptake by at least 20%. Concordant results were shown by 81% of segments. In segments with severe 201Tl reduction discordance was observed in 10% of segments in the LAD territory and lateral wall and i the LAD territory and lateral wall and in 44% of segments in the posterior territory. In segments with moderate 201Tl reduction discordance occurred in 12% or 46% of segments, respectively. Severe defects were defined as the entire area with 201Tl uptake ?50% within a defined territory. Discordance was observed in 6/43 of these. Of 90 areas with sWMA on cineventriculography, 12 showed discordant results. Ten of these 12 discordant areas affected septum or posterior wall. In areas with normal wall motion or only mild hypokinesis, discordance occurred in the septum or posterior wall in 22% whereas the figure for the anterior or lateral wall was only 2%. These results point to a significant role of photon attenuation in 201Tl SPET imaging in the septum and posterior wall. (orig.)

  20. Dual myocardial scintigraphic imaging using 123I-BMIPP and 201Tl in patients with Duchenne's progressive muscular dystrophy

    International Nuclear Information System (INIS)

    Dual single photon emission computed tomography (SPECT) was performed in 30 patients with Duchenne's muscular dystrophy (DMD) using 201 thallium (Tl) for myocardial perfusion 123I-?-methyl-p-iodophenylpentadecanoic acid (BMIPP) for myocardial fatty acid metabolism scintigraphy. The left ventricle was divided into 9 regions, and accumulation of the radiotracers was assessed visually for each region to calculate defect score for each tracer. There was some degree of decrease in the myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP, 70%; Tl, 63%), followed by the posterior wall, lateral wall, and anterior wall. It was less common on the apical side of the ventricular septum for both tracers (BMIPP, 3%; Tl, 17%). Accumulation of Tl was lower than BMIPP in 18/30 patients (60%) and higher in 9 (30%), while both tracers showed equal accumulation in 3 (10%). BMIPP showed higher accumulation than Tl in all regions but the septum. A significant negative correlation was found between the defect scores for both tracers and the left ventricular ejection fraction (LVEF) (r=-0.629 for Tl; r=-0.567 for BMIPP). The strongest negative correlation was that between the sum of the Tl and BMIPP defect scores and the LVEF (r=-0.681). Dual SPECT myocardial scintigraphy with Tl and BMIPP provided an accurate evaluation of the progression of cardiac lesions in DMD by detecting abnormalities of the myocardby detecting abnormalities of the myocardial metabolism of each substance thereby enabling the assessment of left ventricular function. (author)

  1. Precision of electrocardiographic diagnosis of myocardial infarction in the ventricular septal area. Comparison with 201-TlCl scintigraphy and coronary angiography

    International Nuclear Information System (INIS)

    The purpose of this study was to clarify the diagnostic accuracy of 3 electrocardiographic (ECG) indexes including Q waves in V1[QV1(+)], Q waves in V1 and V2 [QV1V2(+)], and absence of septal q waves in V6 [qV6(-)] for prediction of myocardial infarction (MI) in the interventricular septal area (IVS) using 201-TlCl myocardial scintigraphy. In addition, we also evaluated the relationship between these ECG indexes and the site of the culprit lesions in the left anterior descending artery (LAD). This study consisted of 115 patients (100 males; mean age, 60 years) with anteroseptal MI who underwent 201-TlCl myocardial scintigraphy in our hospital between January 1994 and December 1997. One hundred six of them also underwent coronary angiography (CAG). On extent maps obtained from SPECT images of 201-TlCl scintigraphy, the area of MI occupying the IVS area, using the proportion of the defect area in the IVS, was expressed as % defect area (%DA). Three patterns of %DA were defined as follows. A: 50%?%DA?100%; B: 70%?%DA?100%; and C: 90%?%DA?100%. On scintigraphic evaluations, %DA in patients with each of the 3 ECG indexes was significantly larger than %DA in patients without them (p=0.0002, p=0.0008, and p=0.0008, respectively). QV1(+) and qV6(-) showed good sensitivities only for pattern C (79% and 75%, respectively), but all ECG indexes showed low senall ECG indexes showed low sensitivities for patterns A and B. Regarding specificity, QV1V2(+) showed the best values (76% for pattern A, 68% for pattern B, and 68% for pattern C) among the 3 ECG indexes. For prediction of the culprit lesions located proximal to the origin of the first septal branch, qV6(-) showed a relatively good sensitivity (67%) and specificity (67%). For prediction of MI in the IVS area, QV1(+) and qV6(-) showed good sensitivities when the MI was sufficiently large in size. QV1V2(+) showed relatively good specificities irrespective of the MI size. qV6(-) was the best predictive index for the culprit lesions located in the proximal site of the LAD. (author)

  2. Diagnosis of ischemic lesion by 201Tl myocardial three-dimensional polar map. Comparison between before and after administration of Amlodipine

    International Nuclear Information System (INIS)

    In order to apply the three-dimensional polar map using the Application Visualization System-Medical viewer (AVS-MV) in clinical cases, we have conducted the 201Tl myocardial SPECT studies before and after the pharmacotherapy of Amlodipine to thirteen cases with old myocardial infarction. We have visually evaluated the three-dimensional polar maps, and the improvement of the myocardial perfusion of infarct area was observed after administration of Amlodipine in nine out of thirteen cases (69%). Significant improvements of severity score in the entire area of left ventricle were indicated on stress images and delayed images (p<0.05). Significant improvements were also demonstrated in the %Tl uptake and washout rate of infarct areas (p<0.05). With the administration of Amlodipine, improvement of myocardial perfusion was indicated on the exercise stress test. With the use of AVS-MV, the three-dimensional polar map was easy to operate and improved form of myocardial perfusion was observed in the infarct area before and after the administration of Amlodipine on three-dimensional image, although we used the myocardial phantom as the basic image. (author)

  3. Diagnostic accuracy of supine and prone thallium-201 stress myocardial perfusion single-photon emission computed tomography to detect coronary artery disease in inferior wall of left ventricle

    International Nuclear Information System (INIS)

    Prone thallium-201 (201Tl) myocardial perfusion single-photon emission computed tomography (SPECT) reduces false-positive rates when evaluating inferior wall abnormalities by minimizing diaphragmatic attenuation. The present study investigates the diagnostic validity of prone 201Tl stress myocardial perfusion SPECT for detecting coronary artery disease in the inferior wall of the left ventricle in Japanese patients. Of the 104 consecutive patients who underwent 201Tl stress myocardial perfusion SPECT to diagnose coronary artery disease, we evaluated 46 who underwent image acquisition in both the supine and prone positions, and coronary angiography within 3 months thereafter. Images were acquired in the routine supine position immediately following 201Tl (111 MBq) injection and 4 h following early acquisition. Images were acquired in the prone position only during the early phase following supine acquisition. We evaluated the SPECT images of the inferior half segments of the left ventricle using a five-point defect scoring system. According to the coronary angiographic findings, we investigated the diagnostic accuracy of stress-rest supine, stress supine, stress prone, and combined supine-prone images. Reduced uptake in the stress supine image of the combined images was considered as attenuation when uptake was normal in the prone image. The sensitivity of the stress-rest supine, stress supine, stress prone, and stress-combinss supine, stress prone, and stress-combined supine-prone images was 77%, 86%, 55%, and 55%, and the specificity was 71%, 54%, 79%, and 83%, respectively. Diagnostic accuracy was the highest in stress-rest supine images. Prone images tended to improve the specificity of detecting coronary artery disease in the inferior wall, but not diagnostic accuracy compared with stress-rest supine images because of decreased sensitivity. (author)

  4. Clinical significance of 201Tl lung uptake in heart disease

    International Nuclear Information System (INIS)

    In order to evaluate the clinical significance of 201Tl lung uptake, 201Tl myocardial scintigraphy was performed in 675 cases with various cardiac diseases. The lung uptake ratio of 201Tl (L/T) was calculated by ratio of the total radioactivity of the unilateral lung to the injected dose of 201Tl in 69 cases. Using both 201Tl scintigraphy and cardiac pool scintigraphy with 99mTc-human serum albumin, images of 201Tl of the intravascular space and extravascular space were obtained in 14 cases. The image of 201Tl of the extravascular space was almost the same as the original 201Tl image as regards the pattern of 201Tl-distribution, and the lung uptake ratio of the former was 95.7 ± 2.8% of that of the latter. The mean values of L/T of the right and left lungs were 1.5 ± 0.9%, 1.2 ± 0.6% in the healthy lungs, 2.8 ± 1.4% and 1.4 ± 0.7% in heart diseases without left heart failure, and 4.4 ± 1.8% and 2.6 ± 1.2% in those with left heart failure, respectively. Increased lung uptake ratio of 201Tl, which was related to post-capillary pulmonary hypertension, prolonged pulmonary circulation time and findings of left heart failure, was observed more frequently in mitral valvular diseases (72.2%) and dilated cardiomyopathies (60.0%). Increased lung uptake of 201Tl was associated with normal or increased pulmonary perfusion in many cases or areaary perfusion in many cases or areas, but with pulmonary hypoperfusion in some cases with post-capillary pulmonary hypertension, in whom both increased lung uptake of 201Tl and pulmonary hypoperfusion were shown in the lower lung fields. In conclusion, increased lung uptake of 201Tl suggests increased pulmonary extravascular space and calculation of the lung uptake ratio of 201Tl seems to be useful for the evaluation of left ventricular dysfunction. (author)

  5. Effects of ischemia-reperfusion injury on myocardial single pass extraction and retention of Cu-PTSM in perfused rat hearts: comparison with 201Tl and 14C-iodoantipyrine

    International Nuclear Information System (INIS)

    The effects of ischemia-reperfusion-induced myocardial damage on the single pass extraction and retention of 64Cu-pyruvaldehyde-di-(N4-methylthiosemicarbazone) (64Cu-PTSM) in perfused rat hearts were compared to these effects on that of 201Tl and 14C-iodoantipyrine. 201Tl and 14C-iodoantipyrine did not show significant changes, but in the case of 64Cu-PTSM, the single pass extraction and retention was reduced with reperfusion. These findings indicate that ischemia-reperfusion-induced myocardial damage decrease the generator-produced 62Cu-labeled 62Cu-PTSM extraction and retention, and that 62Cu-PTSM might have potential not only as a blood flow tracer but also as a functional tracer. (author)

  6. Effects of ischemia-reperfusion injury on myocardial single pass extraction and retention of Cu-PTSM in perfused rat hearts: comparison with [sup 201]Tl and [sup 14]C-iodoantipyrine

    Energy Technology Data Exchange (ETDEWEB)

    Wada, Kouichi; Fujibayashi, Yasuhisa; Taniuchi, Hideyuki; Tajima, Naoyuki; Yokoyama, Akira (Kyoto Univ. (Japan). Faculty of Pharmaceutical Sciences); Tamaki, Nagara; Konishi, Junji (Kyoto Univ. (Japan). School of Medicine)

    1994-05-01

    The effects of ischemia-reperfusion-induced myocardial damage on the single pass extraction and retention of [sup 64]Cu-pyruvaldehyde-di-(N[sup 4]-methylthiosemicarbazone) ([sup 64]Cu-PTSM) in perfused rat hearts were compared to these effects on that of [sup 201]Tl and [sup 14]C-iodoantipyrine. [sup 201]Tl and [sup 14]C-iodoantipyrine did not show significant changes, but in the case of [sup 64]Cu-PTSM, the single pass extraction and retention was reduced with reperfusion. These findings indicate that ischemia-reperfusion-induced myocardial damage decrease the generator-produced [sup 62]Cu-labeled [sup 62]Cu-PTSM extraction and retention, and that [sup 62]Cu-PTSM might have potential not only as a blood flow tracer but also as a functional tracer. (author).

  7. The significance of 201Tl/123I MIBG (metaiodobenzylguanidine) mismatched myocardial regions for predicting ventricular tachycardia in patients with idiopathic dilated cardiomyopathy

    International Nuclear Information System (INIS)

    123I-MIBG (MIBG) regional defects in myocardial regions with preserved 201Tl (Tl) uptake have been observed in patients with idiopathic dilated cardiomyopathy (DCM). To evaluate whether the presence of Tl/MIBG mismatched regions is related to the occurrence of ventricular tachycardia (VT), we performed myocardial dual SPECT imaging with Tl (111 MBq) and MIBG (111 MBq) in 17 patients with DCM, 11 (Gp A) with and 6 (Gp B) without VT. Myocardial dual SPECT imaging was performed at 15 minutes after and 4 hours after the tracer injection. The regional tracer uptake was scored visually in 6 segments of the basal, middle, and apical short-axial images and in 2 apical segments of the midventricular vertical long-axial image by a four-point scoring system (0=normal, 1=moderate, 2=severe and 3=complete defect). Then, the severity of tracer maldistributions was assessed by the difference between total defect scores (TDSs) of Tl and MIBG (?TDS). TDS was not different between Gps A and B in both Tl and MIBG images. However, ?TDS was larger in Gp A than in Gp B (13.5±6.5 vs. 5.8±3.0, p<0.05). Also, the number of segments with the mismatched tracer uptake was larger in Gp A than in Gp B (12.5±3.0 vs. 8.3±1.5, p<0.01). In the electrophysiologic study, we found that the fractionated area corresponded to the mismatched region in 3 of 5 patients in Gp A. These results suggest that regional sympathetic denervation is a possible factor which provocates VT, and ble factor which provocates VT, and myocardial dual SPECT imaging with Tl and MIBG is a useful method for predicting VT in patients with DCM. (author)

  8. Computer-aided semi-quantitative myocardial scintiscanning using 201-Tl in routine examinations to diagnose coronary heart disease

    International Nuclear Information System (INIS)

    Thallium-201 is generally used for intravenous myocardial scintiscanning. In the 42 patients investigated during the study, the sensitivity of this method in the diagnosis of reduced myocardial perfusion was judged to be superior to that of exercise electrocardiography. The most reliable conclusions could, however, be drawn from the combined results of both these non-invasive techniques. Coronary angiography was carried out for reasons of comparison and proved that the method under investigation, even though showing an extremely high sensitivity, was less satisfactory as regards specifity. Myocardial scintiscanning using thallium-201 constitutes the only non-invasive technique suitable for the evaluation of cardial microcirculation. It must therefore be regarded as an ideal diagnostic tool to be used in combination with coronary angiography which, in turn, provides evidence of macroscopic changes. Moreover, myocardial scintiscanning using thallium-201 still remains the only procedure permitting acute myocardial infarction to be detected within the first few hours following the incident. (TRV)

  9. Relation between myocardial damage and disease activity in patients with systemic lupus erythematosus by exercise 201Tl scintigraphy

    International Nuclear Information System (INIS)

    Myocardial damage in patients with systemic lupus erythematosus (SLE) was evaluated using exercise thallium-201 myocardial scintigraphy, and the relationship between myocardial damage and disease activity of SLE was examined. Twenty-seven patients (26 women and 1 man, mean age 43 years), in whom extramural coronary artery lesions were excluded by coronary angiogram or presumed to be excluded by exercise electrocardiogram, were enrolled in this study. The mean duration of disease and the mean duration of corticosteroid therapy in these patients were 94 and 77 months, respectively. Exercise thallium-201 scintigraphy was performed twice (mean interval, 30 months) to evaluate the progression of myocardial damage. Myocardial ischemia as an index of myocardial damage was evaluated by visual analysis and ischemic score (IS). The changes in myocardial ischemia were categorized into 3 groups: improved, unchanged or worsened. The disease activity of SLE was determined by the SLE Disease Activity Index (SLEDAI), and the changes in this index were classified into the same three categories, as evaluated every six months between the two scintigraphic examinations. Disease activity was significantly correlated with myocardial ischemia (p<0.05), and with myocardial ischemia as diagnosed by ?IS (difference in ischemic score between the first and second thallium-201 scintigrams: p<0.005). But neither the duration of disease nor the duration of corticosteroid therapy was correlated witcorticosteroid therapy was correlated with IS at the first scintigraphy. These results indicate that control of SLE disease activity may be critical in the treatment of myocardial damage resulting from vascular lesions, especially intramyocardial small-artery disease, in patients with SLE. (author)

  10. Relation between myocardial damage and disease activity in patients with systemic lupus erythematosus by exercise {sup 201}Tl scintigraphy

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    Kuzumoto, Masayuki [Nara Medical Univ. (Japan)

    1997-08-01

    Myocardial damage in patients with systemic lupus erythematosus (SLE) was evaluated using exercise thallium-201 myocardial scintigraphy, and the relationship between myocardial damage and disease activity of SLE was examined. Twenty-seven patients (26 women and 1 man, mean age 43 years), in whom extramural coronary artery lesions were excluded by coronary angiogram or presumed to be excluded by exercise electrocardiogram, were enrolled in this study. The mean duration of disease and the mean duration of corticosteroid therapy in these patients were 94 and 77 months, respectively. Exercise thallium-201 scintigraphy was performed twice (mean interval, 30 months) to evaluate the progression of myocardial damage. Myocardial ischemia as an index of myocardial damage was evaluated by visual analysis and ischemic score (IS). The changes in myocardial ischemia were categorized into 3 groups: improved, unchanged or worsened. The disease activity of SLE was determined by the SLE Disease Activity Index (SLEDAI), and the changes in this index were classified into the same three categories, as evaluated every six months between the two scintigraphic examinations. Disease activity was significantly correlated with myocardial ischemia (p<0.05), and with myocardial ischemia as diagnosed by {Delta}IS (difference in ischemic score between the first and second thallium-201 scintigrams: p<0.005). But neither the duration of disease nor the duration of corticosteroid therapy was correlated with IS at the first scintigraphy. These results indicate that control of SLE disease activity may be critical in the treatment of myocardial damage resulting from vascular lesions, especially intramyocardial small-artery disease, in patients with SLE. (author)

  11. A case of myotonic dystrophy presenting an acute inversion of T wave and positive findings in 201Tl and 99mTc-PYP myocardial scintigram

    International Nuclear Information System (INIS)

    In a 66-year-old man with myotonic dystrophy, ECG showed repeated occurrence of Mobitz II type second degree of atrioventricular block and acute inversion of T wave. Thallium-201 myocardial single photon emission computed tomography (SPECT) showed defect images corresponding to hypokinesis in the anterolateral wall and apex that were detected on left ventriculography. Tc-99m PYP myocardial SPECT showed abnormal uptake in the posteroinferior wall. Positive findings on myocardial SPECT seemed to indicate myocardial degeneration associated with myotonic dystrophy because there was histological evidence of myocardial degeneration despite the lack of abnormal findings on coronary arteriography. ECG findings are also worthy to note because T waves became deteriorated in a short time. (Namekawa, K)

  12. Ability of 201Tl and 123I-BMIPP mismatch to diagnose myocardial ischemia in patients with suspected coronary artery disease

    International Nuclear Information System (INIS)

    A mismatch defect between 201TL and 123I-beta-methyliodophenylpentadecanoic acid (BMIPP) dual isotope SPECT (d-SPECT) is useful to detect myocardial ischemia in patients with acute coronary syndrome. However, whether mismatched d-SPECT findings reflect actual myocardial ischemia in stable patients with suspected, but unknown ischemic heart disease is unclear. The present study assesses the significance of a d-SPECT mismatch among such patients. Forty-nine patients with suspected stable coronary heart disease who had been referred for chest pain, electrocardiogram (ECG) abnormalities or multiple risk factors (66±11 years old, 34 males) with a d-SPECT mismatch participated in this study. All of them underwent coronary angiography (CAG) to assess coronary artery disease. The entire myocardial area on d-SPECT images was divided into 17 segments, each of which was scored from 0 (normal) to 4 (defect). The d-SPECT mismatch score (MS) was defined as the summed BMIPP defect score (BM-TDS) minus the summed defect score (TL-TDS). The inclusion criterion was MS?1, and the mismatch was defined as true positive if the mismatched area was concordant with the territories supplied by significant coronary stenotic arteries by CAG. Ischemic heart disease was judged by coronary angiography in 31 (63%) patients (IHD group), of which 24 (49.0%) were true positives. Of the remaining 18 (37%) patients without no significant coronary stenosis (non-IHD group), 12 (24%onary stenosis (non-IHD group), 12 (24%) had some types of organic heart disease. If MS?4 was defined as the threshold for an ischemic positive mismatch, then the sensitivity and specificity were 80% and 63%, respectively. However, mismatch scores did not significantly differ between the groups with true positive-IHD and organic heart disease in non-IHD group (6.6±4.4 vs. 6.4±3.7). A d-SPECT mismatch score of ?4 was an appropriate cutoff at which diagnosis of myocardial ischemia in patients who were screened for ischemic heart disease. However, since patients with non-ischemic but organic heart disease can also present with abnormal mismatch findings, coronary angiography or CT might be warranted to differentiate IHD from non-IHD. (author)

  13. Diagnosis of acute myocardial infarction using dual SPECT (99mTc PYP and 201Tl Cl) method

    International Nuclear Information System (INIS)

    We investigated the usefulness of the dual SPECT method with the Tc-99m and Tl-201 in comparison with the conventional Tc-99m planar method. Myocardial scintigraphy was performed in 57 patients with acute myocardial infarction; 30 were assessed by the conventional planar method and 27 by the dual SPECT method. The accumulation ratio of Tc-99m (%Tc) by the dual SPECT method was calculated from the coronal image and was compared with the serum values of total CPK, peak CPK, total CPK-MB, and peak CPK-MB obtained from serial sampling and the LVEF obtained by a left ventriculography a month later. The sensitivity for diagnosis of myocardial infarction was 73.3% by the planar method and 88.9% by the dual SPECT method. The infarct sites were identified in 61.5% of the antero-septal lesion, in 35.7% of the infero-posterior lesion and in 66.7% of the lateral lesion using the planar method, while using the dual SPECT method were 100% identification for both antero-septal and lateral lesions, and 75% for the infero-posterior lesion. The highest correlation, with a rate of 0.854, was between the %Tc and the total CPK. The %Tc also showed a positive correlation with peak CPK (r=0.798), with total CPK-MB (r=0.792) and with peak CPK-MB (r=0.751) (p<0.01). The LVEF had a tendency to decrease as %Tc exceeded 30%. The dual SPECT method was superior to the conventional planar method in detecting, in identifying the site and in evaluating the size of myocardial infarction. It also showeze of myocardial infarction. It also showed a high correlation between the %Tc and the LVEF at chronic stage of myocardial infarction. (author)

  14. Incremental value of 24-hour delayed imaging in 201Tl stress myocardial perfusion studies (MPS) with an 'early rest reinjection' protocol

    International Nuclear Information System (INIS)

    Full text: One hundred patients (pts) undergoing stress MPS had 24 h imaging for fixed defects at 4 h delayed imaging. 53 had prior myocardial infarction (MI) and 71 were males. Stress employed isotonic exercise with dipyridamole (0.56 mg kg-1) infusion in 57 pts, exercise alone in 33 and dipyridamole alone in 10. All pts with stress defects had rest-reinjection of 40 MBq of 201Tl after stress imaging had been completed, and most had sublingual nitrate therapy 10 min before reinjection. MPS from the 100 pts (15% of total) were read without clinical data, using a 20 segment scoring system. 51 pts showed -2 segments improvement between 4 and 24 h scores, but 22 pts had shown reversibility between stress and 4 h imaging and the further change did not alter interpretation. The other 29 pts (group A) showed clinically important change in 24 h scores, leaving 71 pts without clinical change (group B). Segmental improvement between 4 and 24 h in group A was 4.62 ± 2.18 and 1.18 ± 1.48 in group B (P = 0.02). Group A stress defect scores were not greater (10.90 ± 3.60) or more severe (3.72 ± 3.06) than in group B (8.92 ± 4.34 and 2.79 ± 3.11); 18 group A pts had MI compared with 38 group B pts. No significant correlation was found between improved 4-24 h scores and parameters of stress-LV dysfunction. There is benefit from 24 h, 201TI MPS in patients with persisting 4 h defects, despite early rest-reinjection and acute nitrate therapyction and acute nitrate therapy

  15. Comparison of adenosine and exercise stress 201Tl myocardial perfusion imaging for diagnosing coronary heart disease in women

    International Nuclear Information System (INIS)

    Objective: To compare the diagnostic value of adenosine and exercise stress myocardial perfusion imaging (MPI) for detecting coronary heart disease (CHD) in women. Methods: One hundred and thirty-eight patients with CHD were randomly divided into two groups: adenosine stress group (n=69)and exercise stress group (n=69). All patients underwent myocardial SPECT evaluation. Coronary angiography (CAG), referred as 'gold standard' , was performed in each patient within 1 week before or after MPI. The diagnostic value of the two stress MPI was compared with ?2 test or Fisher's exact test. Results: In adenosine stress group, the sensitivity, negative predictive value and accuracy were 88.2% (45/51), 72.7% (16/22), 88.4% (61/69), respectively, which were not significantly different from those of the exercise stress group (91.7% (44/48), 66.7% (8/12), 81.2% (52/64); ?2 =0.571, 0.714, 0.249, P>0.05). However, the false positive rate of adenosine stress (11.1%, 2/18) was significantly lower than that of exercise stress (50.0%, 8/16), P=0.023. Conclusions: Adenosine and exercise stress MPI have similar value for CHD diagnosis in women, however, adenosine stress MPI may have an advantage of low false positive rate. (authors)

  16. The white-hole phenomenon - a potential parameter of function in non-gated 201Tl myocardial scintigraphy

    International Nuclear Information System (INIS)

    In 50 patients with a ''white hole'' in their scintigram - among them 44 patients with a history of myocardial infarction - the relation between its relative volume and the ventriculographically determined ejection fraction was studied retrospectively. A relative volume of the ''white hole'' larger than 13.7% showed a specificity of 93% and a sensitivity of 45% for a decreased ejection fraction and had a significant correlation of r=-0.54 (alpha=0.01) with the ejection fraction. Thus the relative volume of the ''white hole'' derived automatically from 221TI-SPECT is an easy-to-determine additional parameter which allows an at least semiquantitative statement about the function of the left ventricle. (orig.)

  17. Differentiation of transiently ischemic from infarcted myocardium by serial imaging after a single dose of 201Tl

    International Nuclear Information System (INIS)

    Myocardial 201Tl uptake and regional blood flow by the microsphere technique were determined in anesthetized dogs undergoing either 20 min of coronary occlusion and 100 min of reperfusion (N = 10) or 120 min of occlusion (N = 4). In both groups, 201Tl was injected intravenously after 10 min of occlusion. In transiently occluded dogs, regional flow at the time of 201Tl administration was reduced to 8 +- 3 percent of normal flow in endocardial layers of the central ischemic zone. After 100 min of reperfusion, flow values were not significantly different from normal. 201Tl activity after reperfusion rose to 56 +- 5 percent of normal, demonstrating that redistribution of the radionuclide occurred during the reflow period. In animals with persistent occlusion, there was a significant relationship between 201Tl uptake and flow (r = 0.95) and no evidence of redistribution of 201Tl during the two hour occlusion period. In another five dogs receiving 201Tl, serial gamma camera images obtained during reperfusion showed increasing uptake of the tracer in apical defects which returned to normal by 4 hours of reflow. Thirteen patients with stable angina received 2 mCi of 201Tl intravenously at peak exercise, and multiple gamma camera images obtained serially. All demonstrated zones of diminished 201Tl uptake 10 min after exercise. Defects which disappeared within 1-6 hours postexercich disappeared within 1-6 hours postexercise corresponded to areas supplied by coronary arteries with significant stenoses. Persistent defects were present in regions of old myocardial infarction. Six patients with acute myocardial infarction demonstrated 201Tl myocardial defects which showed no significant change over 6 hours. Redistribution of 201Tl into ischemic myocardium was demonstrated during transient coronary occlusion in dogs and after exercise stress in man

  18. Clinical validation of simultaneous dual-isotope myocardial scintigraphy

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    Simultaneous dual-isotope (rest thallium-201/stress technetium-99m sestamibi) myocardial single-photon emission tomography (SPET) would be an ideal procedure; however, 99mTc cross-talk on the 201Tl window hampers its routine use. Photon energy recovery (PER) is a spectral deconvolution technique validated for scatter and cross-talk removal in phantom studies and a limited series of patients. In this study we aimed to validate the technique in 295 patients within a context of clinical routine practice. Conventional separate rest 201Tl myocardial SPET data sets were visually compared with simultaneous dual-isotope data sets corrected by PER. Conventional separate rest 201Tl data sets were identical to dual PER-corrected 201Tl data sets in 173 (58.6%) patients. As dual PER 201Tl data sets are corrected for 99mTc cross-talk but also for 201Tl scatter, they were compared with separate rest 201Tl data sets corrected by PER in the 122 discordant patients. No difference was found in 77 (26.1%) patients. In 26 (8.8%) patients, the difference consisted in the presence of a defect on dual PER 201Tl data sets only, mirroring an ischaemic defect on 99mTc-sestamibi data sets. This difference can be attributed to the influence of stress on the kinetics of 201Tl injected at rest. In the remaining 19 (6.4%) patients, the difference between separate and sits, the difference between separate and simultaneous PER-corrected data sets was scored as mild in 11 and moderate in eight patients and seemed to be related to multiple methodological factors. It is concluded that PER correctly removes 99mTc cross-talk. With the addition of an appropriate attenuation correction, the PER technique may allow the routine use of simultaneous dual-isotope myocardial scintigraphy in the near future. (orig.)

  19. Multimodality MRI in determination of myocardial viability: comparison with positron emission tomography and single photon emission computed tomography

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnostic value for myocardial viability by using various imaging methods. Methods: Chronic myocardial ischemia animal model in 10 pigs were established and underwent multi-modality MR imaging, PET(positron emission tomography) and 201Tl SPECT(single photon emission computed tomography) before and after 1 to 2 month modeling respectively. The size of myocardial ischemia and necrosis was judged and compared with pathological findings to assess the sensitivity and specificity of various methods. Results: 7 pigs completed all examination successfully. At rest-cine MRI, 10 (8.93%) segments were akinetic, 4 (3.57%) segments were mild hypokinetic and 2 (1.78%) segments were severely hypokinetic. During dobutamine infusion, 10 (8.93% ) segments were akinetic. Perfusion was abnormal in 34 (30.36%) segments. Delayed hyper enhancement was observed in 12 (10.71%) segments. PET showed 17 (15.18%) segments of myocardial necrosis. SPECT showed 9 (8.04%) segments of myocardial necrosis. Triphenyl tetrazolium chloride (TTC) determined 14 (12.50%) segments of pale necrosis. Necrosis segments determined by PET significantly higher than contrast-enhanced MR imaging (?2=5, P=0.0253, Kappa=0.8028) and cine MRI (?2=7, P=0.0082, Kappa=0.7079), it was also higher than TTC (?2=3, P=0.0833, Kappa=0.8879), but had no significant statistic difference. Necrosis segments determined by SPECT was significantly lower than TTC SPECT was significantly lower than TTC (?2=5, P=0.0253, Kappa=0.7590). Necrosis segments determined by cine MR was significantly lower than TTC (?2=4, P=0.0455, Kappa=0.8100). Necrosis segments determined by contrast-enhanced MRI had no significant statistic difference with TTC (?2=2, P=0.1573, Kappa=0.9130). Using TTC as the gold standard, the sensitivity and specificity of cine MRI, contrast-enhanced MRI, PET and SPECT in the determination of unviable myocardium were 71.43%, 100.00%; 85.71%, 100.00%; 100.00%, 96.94% and 64.29%, 100%, respectively. Conclusion: Cardiac MRI can provide information of morphology, function and perfusion for determining viable myocardium, delineate the location and degree of necrosis myocardium clearly, demonstrate wall motion of left ventricular directly which is cheaper than PET. PET slightly overestimates extent of necrosis myocardium and can't distinguish transmural necrosis from subendocardial necrosis. MRI has high consistency with PET and pathology result. (authors)

  20. Hemodynamic significance of diffuse lung uptake of 201Tl in heart diseases

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    Clinical significance of diffuse lung uptake of 201Tl was studied in 244 cases of various heart diseases. The grade of lung uptake of 201Tl was assessed by total lung uptake ratio (L/T), maximal lung uptake ratio (Max/T), lung to myocardium or mediastinum counts ratio (M/H or M/Med) and visual grade. L/T, Max/T, M/H and M/Med were directly correlated with pulmonary arterial pressure (PCW), and inversely correlated with cardiac output (CO) and cardiac index (CI). Among them, L/T was the best index to assess PCW, that was correlated with PCW (r=0.65), CO (r=-0.53) and CI (r=-0.45). The visual grade of 201Tl lung uptake was correlated with L/T, and the increased lung uptake was associated with a higher PCW and a lower CO as well as a lower CI. Diffuse increased lung uptake of 201Tl was observed in 29 of 41 cases (70.7%) with myocardial infarction, 25 of 29 cases (86.2%) with mitral valvular diseases and 9 of 10 cases (90.0%) with combined valvular diseases, in addition, in most cases with left heart failure and cases of NYHA 3 and 4, but that was not rarely observed in cases of NYHA 2 and without left heart failure. In heart diseases, 201Tl myocardial scintigraphy seems to be valuable for detection of left heart failure including pulmonary congestion and interstitial pulmonary edema. Total lung uptake ratio (L/T) may be useful for estimation of PCW, and the visual grade of 201Tl lung uptake may be applicabup>201Tl lung uptake may be applicable as routine index for grading of lung uptake of 201Tl. (author)

  1. Clinical value of iodine-123 beta-methyliodophenyl pentadecanoic acid (BMIPP) myocardial single photon emission computed tomography for predicting cardiac death among patients with chronic heart failure

    International Nuclear Information System (INIS)

    In the present study, the effectiveness of 123I-?-methyliodophenyl pentadecanoic acid (BMIPP) single photon emission computed tomography (SPECT) for predicting cardiac death of patients with chronic heart failure was evaluated. Abnormalities of fatty acid metabolism are found in patients with chronic heart failure and BMIPP was developed as a tracer for scintigraphic assessment of myocardial fatty acid utilization. The study group comprised 74 patients with chronic heart failure with a left ventricular ejection fraction (LVEF) 201Tl SPECT and BMIPP SPECT. The uptake of tracer was scored semiquantitatively from 0 (normal) to 4 (defect) in 20 segments and a total defect score (TDS) for all 20 segments was calculated. On planar images the mediastinum to heart count ratio (H/M) was calculated for the BMIPP and Tl studies, and the H/MBMIPP:H/MTl (H/MBMIPP divided by H/MTl) was also calculated. The mean follow-up period was 660 days and there were 17 cases of cardiac death. Multivariate analysis identified H/MBMIPP:H/MTl (pBMIPP:H/MTl was situated to the left relative to LVEF. Analysis of the myocardial metabolism by BMIPP SPECT can predict the high-risk patients wPECT can predict the high-risk patients with chronic heart failure. (author)

  2. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

    International Nuclear Information System (INIS)

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography (201Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting 201Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by 201Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting 201Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  3. Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly

    International Nuclear Information System (INIS)

    Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise 201Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n=56), 30-44 (n=143), 45-54 (n=311), 55-64 (n=498), 65-74 (n=402), and 75-88 (n=98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of 201Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for 201Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise 201Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than 201Tl SPECT. (author)

  4. 201Tl scintiscanning of the myocardium following radiotherapy of the thoracic region

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    40 patients were examined by 201Tl scintiscanning after radiotherapy of the thoracic region in breast cancer and metastasizing testicular tumors, resp. The results allowed to evaluate the clinical and electrocardiographic findings in 105 follow-up patients. From 40 patients with the greater part having no cardiac symptoms, 22 revealed irreversible 201Tl fixation disturbances and 10 storage deficiency under stress with repletion after rest. These findings are interpreted as myocardial fibrosis or ischemic reaction due to radiotherapy and conclusions for follow-up checks are recommended

  5. Thyroid scanning with 201Tl-chloride

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    Thyroid scanning with 201Tl-chloride was performed on 32 cases of thyroid pathology, comparing with that with sup(99m)Tc, 3 cases of follicular adenocarcinoma, 10 cases of papillary adenocarcinoma, 2 cases of mixed type of follicular and papillary adenocarcinoma, a case of poorly differentiated squamous carcinoma, a case of Huerthle cell carcinoma, 8 cases of follicular adenoma, 5 cases of chronic thyroiditis, a case of subacute thyroiditis and a case of Basedow's disease. The most important evidence of thyroid scanning with 201Tl-chloride is the hot nodule in primary malignant tumor and also metastasis in the mediastinal area. (auth.)

  6. Efficacy of iodine-123-15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid single photon emission computed tomography imaging in detecting myocardial ischemia in children with Kawasaki disease

    International Nuclear Information System (INIS)

    To evaluate its efficacy in detecting myocardial ischemia in children, iodine-123-labeled 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) imaging was performed in 16 pediatric patients with Kawasaki disease (KD, 11 male, 5 female; mean age and range: 13 years 8 months and 8 years 11 months to 17 years 7 months). Five children with chest pain and no cardiac disease were studied as controls (2 male, 3 female; mean age and range: 13 years 4 months and 9 years 4 months to 17 years 11 months). Selective coronary angiography was also performed in the 16 patients to evaluate the location of coronary stenosis and coronary aneurysms. The SPECT images were expressed as polar maps (Bull's eye maps) and the 'defect' area was defined as where the uptake of BMIPP was less than the standardized BMIPP images of the 5 control children. In the 16 patients, 33 segments had coronary aneurysms and 10 (10/33: 30.3%) had significant coronary stenosis on selective coronary angiography. Nine of the 10 (90%) segments with significant coronary stenosis showed a defect on the BMIPP image whereas only 6 of the 23 (26.1%) segments without coronary stenosis showed a defect on BMIPP imaging. The sensitivity of BMIPP SPECT imaging for detection of coronary stenosis was 90% (9/10) and its specificity was 73.9% (17/23), whereas the sensitivity of 201Tl SPECT imaging was 80% (8/10) and its specificity was 60% (14/23). Ther and its specificity was 60% (14/23). There was no significant difference between the BMIPP and 201Tl SPECT images in either the sensitivity or specificity for the detection of coronary stenosis. In the present series, only one case had discordant BMIPP uptake (BMIPP uptake201Tl uptake) in which there was a large coronary aneurysm and re-canalization after complete obstruction at segment 1 of the right coronary artery. This discordant BMIPP uptake reflects the possibility of ischemic but viable myocardium after re-canalization of a large aneurysm in KD. In conclusion, BMIPP SPECT imaging is useful for detecting the areas of ischemic myocardium caused by coronary artery stenosis in children with KD. (author)

  7. 201Tl-redistribution analysis in early and delayed myocordial scintigrams of patients with coronary heart disease (CHD)

    International Nuclear Information System (INIS)

    Scans were performed on 8 healthy subjects and 25 with coronary heart disease proven by angiography and ventriculography including 6 with previous myocardial infarction at rest, exercise, and 1 and 2 h after exercise. Data were collected by a gamma camera interfaced to a data collection system. In healthy subjects 201Tl distribution was homogeneous at rest and after exercise, the count rate ranging between 100% - as set in the region of maximum - and 80% over other regions of myocardium. In 19 patients with coronary heart disease it was uniform only at rest; 6 patients with previous myocardial infarction had locally diminished 201Tl uptake even at rest. In patients with coronary heart disease without previous myocardial infarction, scans made immediately after exercise showed significant 201Tl hypofixation in region of minimum, the count rate of which was less than 80% of the count rate as determined over region of maximum, 201Tl uptake. Scans made 1 and 2 h after exercise had filling-in of 201Tl within the region of minimum the count rate of which returned to the normal range of at least 80% of the count rate measured over region of maximum uptake. This return to resting distribution was called 201Tl redistribution. Six patients with coronary heart disease and previous myocardial infarction had 201Tl defects larger after exercise than at rest, without redistribution being observed. Redistribt redistribution being observed. Redistribution in late postexercise scans is a sign of reversible ischemia in coronary heart disease. Scans at rest may be omitted in coronary heart disease, because transient ischemia is undetectable, unless spontaneous angina occurs during scan procedure. (orig.)

  8. A comparison of prone SPET and left lateral (decubitus) planar imaging for inferior wall attenuation artefact in 201Tl myocardial imaging

    International Nuclear Information System (INIS)

    Full text: Inferior wall attenuation artefacts are a major problem in supine SPET (S-S) myocardial perfusion imaging. SPET imaging with the patient lying in the prone position (P-S) and left lateral planar imaging with the patient lying in the right lateral decubitus position (LL) ameliorate this artefact. This study attempts to define the clinical role of P-S and LL imaging in characterizing S-S inferior wall defects. 21 patients with an inferior wall defect on S-S then had LL and rapid P-S imaging. All images were performed with a GE Optima NX gamma camera using GENIE acquisition and processing. All SPETs used 16 stops (32 frames) through 90 deg, with 40 s per stop for SS and 14 s per stop for P-S. LL images were acquired for 150 s. All images were assessed for adequacy and inferior wall scored for 0 = no, 1 mild, 2 moderate and 3 = severe defects. Statistical analysis was performed using the Wilcoxon rank sum test for matched pairs. All images were adequate for analysis. Significantly fewer defects were seen in P-S vs S-S, LL vs S-S (P 0.88); however; there was a difference (P < 0.05) in the subgroup (n = 7) with moderate defects on S-S imaging but no LL defect. In conclusion, most inferior wall defects seen on S-S imaging can be attributed to either attenuation or true perfusion defects with the use of LL imagingrfusion defects with the use of LL imaging. Prone imaging may only be helpful where the inferior defect is of moderate severity but no LL defect is seen

  9. Myocardial stunning in hypertrophic cardiomyopathy: recovery predicted by single photon emission computed tomographic thallium-201 scintigraphy

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    A young woman with hypertrophic cardiomyopathy confirmed by echocardiography and cardiac catheterization presented with chest pain and features of a large left ventricular aneurysm. The initial diagnosis was myocardial ischemia with either an evolving or an ancient myocardial infarction. Subsequently, verapamil therapy was associated with complete resolution of the extensive left ventricular wall motion abnormalities, normalization of left ventricular ejection fraction and a minimal myocardial infarction. Normal thallium uptake on single photon emission computed tomographic scintigraphy early in the hospital course predicted myocardial viability in the region of the aneurysm. Thus, orally administered verapamil may reverse spontaneous extensive myocardial ischemia in hypertrophic cardiomyopathy and possibly limit the extent of myocardial infarction in such circumstances

  10. 201Tl-SPECT in low-grade gliomas: diagnostic accuracy in differential diagnosis between tumour recurrence and radionecrosis

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    The aim of this work was to describe the usefulness of a simple 201Tl single-photon emission computed tomography (SPECT) technique in the differential diagnosis between tumour recurrence and radionecrosis during the follow-up of patients treated for low-grade gliomas. The study population comprised 84 patients treated for low-grade gliomas who showed suspicion of tumour recurrence during their follow-up. All patients were examined by neuro-anatomical imaging procedures (CT, MRI) and 201Tl-SPECT. 201Tl-SPECT images were assessed by visual analysis based only on the information on the prescription form and by estimation of the uptake index (ratio of mean counts in the lesion to those in the contralateral mirror area). Examiners were blinded to the results of other tests. Under these conditions, the neuro-anatomical procedures yielded 26.2% inconclusive reports, with a global diagnostic accuracy of 0.61, a sensitivity of 0.63 and a specificity of 0.59. The global diagnostic accuracy for 201Tl-SPECT was 0.83, with a sensitivity of 0.88 and a specificity of 0.76. Diagnostic pitfalls were observed in regions with physiological 201Tl uptake, i.e. the posterior cranial fossa, diencephalon, lateral ventricles and cavernous and longitudinal venous sinuses. An uptake index cut-off value of 1.25 showed a sensitivity of 0.90 and specificity of 0.80 for detection of tumour activity. 201Tl-SPECT has adequate diagnostip>201Tl-SPECT has adequate diagnostic accuracy to be part of routine algorithms in the follow-up of patients with low-grade glioma suspected of tumour recurrence, as an alternative to neuro-anatomical procedures and not solely as a complementary test. (orig.)

  11. Computer-aided diagnosis in two-phase 201Tl-SPECT of thoracic lesions

    International Nuclear Information System (INIS)

    Aim: the retention index, a traditionally quantitative analysis of two-phase 201Tl single photon emission computed tomography (SPECT) of the chest, is manually calculated by experienced physicians from comparable 2-D ROI. However, a 3-D ROI would provide more information than a 2-D ROI extracted from a single frame of SPECT. We propose a new diagnostic system, computer-aided diagnosis (CAD), to automatically detect suspicious lesions as 3-D objects on chest 201Tl-SPECT, and assist the physician in interpreting these images. Patients, methods: seventy patients with thoracic lesions and confirmed diagnoses were enrolled to test this automatic CAD system. The reliability of the CAD system in detecting lesions as 3-D objects was compared to the 2-D ROI of 201Tl-SPECT found by the manually visualized method. Furthermore, we also proposed a novel index, the retention index using the heart (RIH), to differentiate high retention (slow clearance, increasing target to heart ratio) as a criterion for a malignant lesion, from low retention (faster clearance, small or no increase of the target to heart ratio) for benign lesions. Results: the CAD system can achieve a detection rate of 100% in automatically searching for thoracic lesions in 201Tl-SPECT. In diagnostic performance, the CAD system with the RIH of comparable 3-D objects has an area under the ROC curve of 0.86, higher than the 0.78 of the traditional RI method (p = 0.198). Conche traditional RI method (p = 0.198). Conclusion: the CAD system of two-phase 201Tl-SPECT is a promising tool for detecting and diagnosing thoracic lesions with a diagnostic accuracy of 0.81. (orig.)

  12. Identification of viable myocardium using 99mTc-tetrofosmin scintigraphy. Comparison with 201Tl redistribution-reinjection images

    International Nuclear Information System (INIS)

    The purpose of this study was to clarify the diagnostic value of identifying viable myocardium using 99mTc-Tetrofosmin scintigraphy. Twenty-one patients with chronic coronary artery disease were studied using 201Tl exercise myocardial scintigraphy with reinjection and 99mTc-Tetrofosmin exercise myocardial scintigraphy. All patients had a history of old myocardial infarction. For 99mTc-Tetrofosmin scintigraphy, 222 MBq of 99mTc-Tetrofosmin was injected during exercise, and exercise images were obtained 20 min thereafter. Three hours later, 666 MBq of 99mTc-Tetrofosmin was injected at rest, and images were obtained 40 min and 220 min later. Myocardial viability in the 99mTc-Tetrofosmin scintigraphy was estimated as fill-in findings (FF) or over 50% of %RI uptake (%TF) in the rest image. Myocardial viability in the 201Tl scintigraphy was estimated as redistribution (RD), full-in findings in the reinjection image (FR) or over 50% of %RI uptake in the reinjection image (%TL). Sixteen of the 21 patients (76%) who underwent 201Tl scintigraphy (RD 10, FR 3, %TL 3 cases) and 15 of the 21 patients (71%) who underwent 99mTc-Tetrofosmin scintigraphy (FF 11, %TF 4 cases) had viable myocardium in the infarcted area. A comparison between the 99mTc-Tetrofosmin rest images obtained 40 min after the injection and that of 220 min revealed no redistribution findings. Tmin revealed no redistribution findings. The %RI uptake of the infarcted area in the resting 99mTc-Tetrofosmin image (47±16%) was slightly lower than that in the 201Tl reinjection image (52±16%). In conclusion, viable myocardium was as clearly identified by 99mTc-Tetrofosmin, as by 201Tl scintigraphy. (author)

  13. The optimum technique for 201Tl tomography of myocardium: an investigation using phantoms

    International Nuclear Information System (INIS)

    Rotating gamma-camera tomography is used for 201Tl perfusion imaging to detect myocardial ischaemia or infarction. Variables which can affect the utility of the images include acquisition time, collimator sensitivity and resolution, spatial filtering, reconstruction matrix and display parameters. An 'Iowa' design myocardial phantom containing 201Tl, with a defect representing an unperfused area, was used to study the effect of these variables. Receiver operator characteristic (ROC) curves and contrast ratios indicated that filtering the acquisition data with a count-dependent (Metz) filter before reconstruction and using a narrow slice width gave best results. No single collimator was superior for all four defect locations investigated but low-energy general purpose and high-resolution collimators were preferred to those with greater sensitivity. Reducing acquisition time by a factor of four compared with that for routine patient imaging affected contrast ratio, uniformity and area under ROC curves insignificantly, provided the optimum reconstruction was used. Displaying tomographic sections in colour gave no improvement in ROC curves over monochrome images. Data acquisition time or administered 201Tl radioactivity might therefore be reduced below the 25 min and 80 MBq often used for patient studies. (author)

  14. Significance of single photon emission computed tomography with Tc-99m pyrophosphate in acute myocardial infarction

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    To examine the value of single photon emission computed tomography with Tc-99m pyrophosphate (PYP-SPECT) in delineating myocardial infarts, 38 patients with documented acute myocardial infarction were studied. Planar imaging (PI) had sufficient ability to detect transmural infarcts; and SPECT requiring much more time for examination is unlikely necessary. In contrast, PYP-SPECT significantly improved sensitivity for delineating subendocardial infarcts (SEI) compared with PI (84 % versus 46 %). Patients with diffuse accumulation of PYP on PI tended to show SEI or inferoposterior infarcts (IPI) on ECG, or merely had blood pool images. Right ventricular accumulation of PYP was visualized in 11 patients on PYP-SPECT, in 2 patients on PI, and in 3 patients on ECG and blood circulation examination; this suggests the usefulness of PYP-SPECT in detecting subclinical right ventricular infarcts (RVI). The results indicate that PYP-SPECT is of value in delineating SEI, IPI, and RVI. (Namekawa, K.)

  15. The interpolated projection data estimation method improves the image quality of myocardial perfusion SPECT with a short acquisition time

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    The interpolated projection data estimation processing (IPDE) method increases the amount of projection data by interpolation of the projection data. We examined the usefulness of the IPDE method for 201Tl myocardial perfusion imaging (MPI) single photon emission computed tomography (SPECT) with a short acquisition time. Forty patients with suspected ischemic heart disease underwent stress 201Tl-MPI SPECT. Both stress and delayed images were acquired with 4 cycles of 360 deg continuous rotation with a 90-direction setting for 14 min. The projection data used for reconstruction were all cycle data (Tl-90-14 min), 2 cycles of data (Tl-90-7 min), and 2 cycles of data processed using the IPDE method (Tl-180IPDE-7 min). This study compared the detection of the perfusion defect by the uptake score and the image quality of 201Tl-MPI SPECT using the normalized mean square error (NMSE). The uptake score of Tl-180IPDE-7 min was significantly more concordant with Tl-90-14 min in comparison to the Tl-90-7 min (p201Tl-MPI SPECT than for the stress 201Tl-MPI SPECT (p201Tl-MPI SPECT for a short acquisition time. Fur SPECT for a short acquisition time. Furthermore, the IPDE method is a simple software program that does not require any expensive equipment or use advanced algorithms. These results suggest that the IPDE method may be useful as an adjunctive method for shortening the acquisition time of 201Tl-MPI SPECT. (author)

  16. Evaluation of [201Tl](III) Vancomycin in normal rats

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    Tl-201 has potential in the preparation of radiolabelled compounds similar to its homologues, like In-111 and radiogallium. In this paper, recently prepared [20'1Tl](III) vancomycin complex ([201Tl](III)VAN) has been evaluated for its biological properties. [20'1Tl](III)VAN was prepared according to the optimized conditions followed by biodistribution studies in normal rats for up to 52 h. The Staphylococcus aurous specific binding was checked in vitro. The complex was finally injected to normal rats. Tracer SPECT images were obtained in normal animals and compared to those of 67 Ga-citrate. Freshly-prepared [201Tl](III)VAN batches (radiochemical yield ? 99%, radiochemical purity ? 98%, specific activity = 1.2 Ci/mmol) showed a similar biodistribution to that of unlabeled vancomycin. The microorganism binding ratios were 3 and 9 for tracer 201Tl3+ and tracer 201Tl(III)DTPA, respectively, suggesting the preservation of the tracer bioactivity. As a nonspecific cell penetrating tracer, [201Tl](III)DTPA was used. (authors)

  17. Gated single photon emission computer tomography for the detection of silent myocardial ischemia

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    Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients. Material and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. All subjects were also subjected to a coronary angiography, whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specificity, accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT. There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873). Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia

  18. Assessment of myocardial perfusion and viability with technetium-99m methoxyisobutylisonitrile and thallium-201 rest redistribution in chronic coronary artery disease

    International Nuclear Information System (INIS)

    We compare thallium-201 rest redistribution and fluorine-18 fluorodeoxyglucose ([18F]FDG) for the assessment of myocardial viability within technetium-99m methoxyisobutylisonitrile (MIBI) perfusion defects in 27 patients with chronic stable coronary artery disease. The following studies were performed: (1) stress 99mTc-MIBI, (2) rest 99mTc-MIBI, (3) 201Tl rest-redistribution single-photon emission tomography, (4) [18F]FDG positron emission tomography. The left ventricle was devided into 11 segments on matched tomographic images. The segment with the highest activity at stress was taken as the reference (activity = 100%). Perfusion defects at 99mTc-MIBI rest were classified as severe (activity 18F]FDG and rest-redistributed 201Tl were recognized as significant if they exceeded 50% of that in the reference segment. Among the 33 segments with severe 99mTc-MIBI rest perfusion defects, 21 had significant [18F]FDG and 10 significant rest-redistributed 201Tl uptake. As regards the 37 segments with moderate defects, [18F]FDG was present in 29 and 201Tl in 31, while of the 134 segments with mild defects, 128 showed [18F]FDG uptake, and 131, 201Tl uptake. In conclusion, there is an inverse relationship between the severity of 99mTip between the severity of 99mTc-MIBI perfusion defects and the uptake of rest-redistributed 201Tl and [18F]FDG. Both tracers are adequate markers of viability in mild and moderate defects; in severe defects 201Tl might underestimate the presence of viability as assessed by [18F]FDG. (orig.)

  19. Evaluating microvascular obstruction after acute myocardial infarction using cardiac magnetic resonance imaging and 201-thallium and 99m-technetium pyrophosphate scintigraphy

    International Nuclear Information System (INIS)

    Few studies have compared the ability of cardiac magnetic resonance (CMR) with that of scintigraphy using 201-thallium (201-Tl) and 99m-technetium pyrophosphate (99m-Tc PYP) to evaluate microvascular obstructions (MOs). In the present study the relationship between the scintigraphic and CMR characteristics of MOs after acute myocardial infarction (MI) was examined. The 14 patients (age 69±8 years, 11 males) underwent 201-Tl/99m-Tc PYP single photon emission computed tomography (SPECT) 7±3 days, initial CMR 16±12 days, and follow-up CMR 193±20 days after a reperfused first acute MI. Each image was analyzed using a 17-segment model. Segmental extent of delayed enhancement (DE), wall motion (WM) and degree of 201-Tl uptake were scored in 238 segments. Of 91 MI segments, MO was recognized in 22 (25%) segments on CMR. WM was significantly better in proportion to 201-Tl uptake (P=0.01) in MO segments. All 8 MO segments with WM improvement at follow-up had 99m-Tc PYP uptake, although only 3 (21%) of 14 MO segments that did not show WM improvement at follow-up had 99m-Tc PYP uptake (P=0.001). 99m-Tc PYP and 201-Tl scintigraphy have the potential to predict WM status and improvement of the MO region after reperfused acute MI. (author)

  20. Gated single-photon emission tomography imaging protocol to evaluate myocardial stunning after exercise

    International Nuclear Information System (INIS)

    This study was designed to apply ECG-gating to stress myocardial perfusion single-photon emission tomography (SPET) for the evaluation of myocardial stunning after exercise. Technetium-99m sestamibi was selected as the perfusion agent and a rest/exercise 1-day protocol was employed. Fourteen patients without coronary stenosis and 33 patients with coronary stenosis were enrolled in the study. We carried out three data acquisitions with ECG-gating: a 15-min data acquisition starting 30 min after the rest injection (AC1), a 5-min acquisition starting 5 min after the stress injection (AC2) and a 15-min acquisition starting 20 min after the stress injection (AC3). Calculation of left ventricular ejection fraction (LVEF) values was performed by means of automatic determination of the endocardial surface for all gating intervals in the cardiac cycle. Measured global EF values in 14 patients without coronary stenosis were 52.3%±7.6% (AC1), 60.6%±8.9% (AC2) and 55.6%±5.6% (AC3), and those in 11 patients with severe ischaemia were 53.6%±8.0% (AC1), 45.6%±12.1% (AC2) and 49.7%±10.7%. The magnitude of the depression of post-stress LVEF relative to the rest LVEF correlated with the severity of ischaemia (r=0.594, P=0.002), and segments manifesting post-stress functional depression were associated with ischaemic segments showing reversible perfusion defects. Stress myocardial perfusion SPET with ECG-gating is a feasible method for the evaluation of myocardial stunning as wellation of myocardial stunning as well as exercise-induced ischaemia. (orig.)

  1. Value of 123I-BMIPP scintigraphy in patients with ischemic heart disease. Comparison with exercise 201Tl SPECT

    International Nuclear Information System (INIS)

    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 thallium (Group 2), wall motion was more severely impaired in Group 1 than in Group 2 (severe hypo- to dyskinesis was present in 32 of 54 segments in group 1 and in 21 of 75 segments in group 2, p201Tl in the segments with stress induced ischemia and wall motion was more impaired in these segments. BMIP was more impaired in these segments. BMIPP myocardial imaging may provide information on metabolic alterations at rest independent of perfusion abnormalities in patients with coronary artery disease. (author)

  2. Quantitative assessment of the thallium-201 myocardial perfusion scintigraphy with single photon emission computed tomography

    International Nuclear Information System (INIS)

    For the basic examination, full width of half maximum and system sensitivity were measured and to investigate the ability for the quantitative assessment of the single photon emission computed tomography (SPECT), count linearity in air and in water were measured, and myocardial phantom and off-axis phantom were employed. For the clinical examination, 42 patients with myocardial infarction (MI) and 22 patients without MI were included in the study Forty-two patients with MI were divided into two groups of 29 anterior MI, and 13 inferior MI. Myocardial area and threshold were employed for receiver operating characteristic (ROC) analysis. There was significant correlation between RI activity and SPECT counts both in air (r = 0.999) and in water (r = 0.999). In the off-axis phantom, the count ratio of the regional wall significantly correlated with regional wall thickness (r = 0.998). From ROC analysis of the criteria, less than 70 % of the maximum activity within the myocardial area of 200 - 2700 was judged as positive. Sensitivity of SPECT was significantly improved compared to multiple planar imaging (MPI) in all MI patients (93 % and 74 %, respectively). In the anterior MI group, sensitivity was greatly improved by SPECT (93 % and 66 %, respectively). However, in the inferior MI group, no significant improvement of the sensitivity was obtained. In the cases with negative in the MPI and positive in the SPECT, small defect size and poor contrast leCT, small defect size and poor contrast lesion were noted. Good correlation was shown between the size of the defect on SPECT and MPI score (r = 0.79) and left ventricular ejection fraction (LVEF) (r = -0.71) in the anterior MI group. (J.P.N.)

  3. A technique of quantifying lung uptake of 201Tl on the scintigram with 201TlCl

    International Nuclear Information System (INIS)

    On intravenous administration of 201TlCl (74 MBq (2 mCi)), initial transit of it through the heart as well as subsequent uptake by the chest were recorded in the supine position using a scintillation camera coupling to a small digital computer, and remaining the patient in the same position perfusion scintigram with sup(99m)Tc-macroaggregated albumin (MAA) or transmi ssion scintigram with a point source of sup(99m)TcO4- too. The radioactivity of total injected dose of 201Tl (T) was calculated from the entire region on the initial transit of the tracer bolus through the heart, and that of unilateral lung (L) was done from the anterior image of 201Tl on which isocount map of the perfusion image or transmission one was superimposed. By these procedures, the lung uptake ratio of 201Tl was calculated by ratio of L/T, and expressed as percentage per entire unilateral lung and mean value (%) per pixel. The average values of the lung uptake ratio in circulatory diseases were 4.0 +- 1.2% in the right lung, 2.7 +- 1.2% in the left lung, and in respiratory diseases 4.5 +- 2.1% and 2.3 +- 1.0%, respectively. This technique is useful to quantify the lung uptake of 201Tl on the lung scintigram with 201TlCl. (author)

  4. Sympathetic reinnervation following heart transplantation: a double-tracer study with 123I-MIBG and 201Tl

    International Nuclear Information System (INIS)

    Sympathetic reinnervation was evaluated in 15 patients 2-69 months after heart transplantation using a double-tracer technique with 123I-MIBG and 201Tl. Since MIBG is accumulated in the same manner as norepinephrine it may serve as a tracer of the integrity and function of the sympathetic nervous system. 201Tl was used for landmarking. Planar anterior imaging was performed 15 min and 4 h after i.v. injection of 220 MBq 123I-MIBG and 37 MBq 201Tl. Image quantitation was based on the ratio of myocardial to mediastinal MIBG-uptake. Cardiac regions of interest were defined according to the 201Tl uptake. There was no evidence of sympathetic reinnervation in 8 patients 2-34 months after transplantation. Increased MIBG-uptake could be observed in the anterior basal region in 6 long-term cardiac transplants (37-69 months). One patient with a 59-month-old transplanted heart did not reinnervate. Increased MIBG-uptake in the anterior basal region indicating partial sympathetic reinnervation could be shown in 40% of the investigated patients with an average organ age of 51 months. (orig.)

  5. Quality of myocardial perfusion single-photon emission tomography imaging: multicentre evaluation with a cardiac phantom

    International Nuclear Information System (INIS)

    The aim of the study was to evaluate quality of myocardial perfusion single-photon emission tomography (SPET) imaging in Finnish hospitals. Nineteen nuclear medicine departments participated in the study. A myocardial phantom simulating clinical stress and rest conditions was filled with routinely used isotope solution (technetium-99m or thallium-201). The cardiac insert included three reversible defects (simulating ischaemia): 30 x 30 x 14 mm3 septal (90% recovery at rest), 30 x 20 x 14 mm3 posterobasal (full recovery) and 20 x 20 x 14 mm3 lateral (full recovery). There were two fixed defects (simulating infarct): 30 x 20 x 14 mm3 postero-apical and 10 x 10 x 6 mm3 apical. The phantom was imaged and interpreted as a myocardial perfusion patient. Reconstruction, printout and reporting were performed according to the clinical routine of each centre. Three nuclear medicine specialists anonymously evaluated the quality of the image sets. The visual scores of the experts were ranked from 1 to 5. Additionally, points from 0 to 8 were given to research reports according to how well perfusion defects were detected. Quantitative points were calculated by comparing background-subtracted and -normalized counts from 12 regions of interest between stress and rest images. Results for technetium studies (12 departments) were better than those for thallium (7 departments). The average visual scores of the experts were 3.7±0.9 fsual scores of the experts were 3.7±0.9 for all image sets, 3.2±0.5 for thallium users and 3.9±0.6 for technetium users (P=0.003). Five laboratories received a low score which, according to the specialists, is barely sufficient for limited clinical use. Average points for the reports were 5.6±2.1, 4.9±1.5 and 6.5±1.7 (P=0.051), and for the quantitation 8.2±1.0, 7.9±0.4 and 8.4±1.1 (P=0.185), respectively. Seven out of 22 interpreters did not detect the lateral 20 x 20 x 14 mm3 defect; five of them used thallium. This study demonstrated the heterogeneity of myocardial perfusion SPET in Finland. The participating laboratories used a wide scale of methods and, sometimes, inappropriate imaging protocols. The need for quality assurance in nuclear cardiology, correct use of SPET instrumentation and objective comparison of clinical studies is evident. The method described is suitable for external quality assurance and quality improvement of myocardial SPET imaging, and is recommended for regular use in nuclear medicine. (orig.)

  6. Detection of myocardial infarction with dual energy CT myocardial iodine maps and perfusion myocardial single photon emission computed tomography scintigraphy: an experimental study in canine

    International Nuclear Information System (INIS)

    Objective: To investigate the feasibility and accuracy of dual energy CT myocardial iodine maps in detecting acute myocardial infarction in canine model. Methods: Myocardial ischemia model was made by ligaturing left anterior descending coronary arteries (LAD) after thoracotomy in six dogs, while another 3 dogs undergoing thoracotomy not ligaturing LAD as control group. Before and three hours after operation, dual-source CT (DSCT) was performed, followed by resting 99Tcm-MIBI single photon emission computed tomography myocardial perfusion imaging. Then, dogs were sacrificed, and the hearts were removed, triphenyketrazolium chloride staining and conventional HE staining were performed. CT number of non-ischemic and ischemic regions were measured and analyzed. The wall of the left ventricle in the short axis was divided into 17 segments, the segments of myocardial perfusion defect in DSCT myocardial iodine maps, SPECT, and pathology were determined. Student t test was used to analyze the difference of CT number between infarcted and non-infarcted myocardium. Kappa test was used for the accuracy of DSCT myocardial iodine maps and SPECT in detecting myocardial ischemia according to the pathological results. Results: No abnormal regions were detected using DSCT myocardial iodine maps in preoperative control and infarction group. After thoracotomy, partial sparse or defective perfusion was consistently noted in six dogs' apical anterior and partition wall in both DSCT myocardial iodine maps and SPECT. In the infarcted group, the attenuation of infarction region (34.75±16.66) HU was significantly decreased compared with preoperative measurements (123.18±15.38 ) HU (t=10.526, P<0.01); decreased perfusion in the infarcted region was also noted in the DSCT myocardial iodine maps and SPECT. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DSCT myocardial iodine maps and SPECT were 85.0% (34/40), 84.1% (95/113), 65.4% (34/52), 94.0% (95/101), and 82.5% (33/40), 90.3% (102/113), 75.0% (33/44), 93.6% (102/109), respectively. Kappa values were 0.63 and 0.71 for the agreement of DSCT myocardial iodine maps and SPECT. Conclusion: DSCT myocardial iodine maps is comparable diagnostic accuracy with rest SPECT myocardial perfusion imaging in detection of acute myocardial infarction in a canine model. (authors)

  7. Clinical evaluation of thyroid scintigraphy with 201Tl chloride

    International Nuclear Information System (INIS)

    Cold nodule demonstrated on the thyroid scan with sup(99m)TcO4- or 131I were imaged with 201Tl chloride. Fourty-eight patients were confirmed histologically and studied whether 201Tl accumulated or not. Thyroid cancers, adenomas and chronic thyroiditis were visualized as positive in 100%, 75.0% and 100% respectively. It was valuable for the diagnosis that all of cystic degeneration of thyroid adenomas were visualized as negative. Further-more, we classified 4 types based on the correlation between conventional thyroid scan and 201Tl thyroid scan. This classification suggested probable diagnosis of nodular goiter. Five of 6 cases of metastasis of thyroid cancer showed as positive nevertheless these lesions were not detected with 131I. (author)

  8. Usefulness of isoproterenol stress thallium-201 myocardial single photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    Twenty patients complaining of chest pain were referred for isoproterenol stress thallium-201 myocardial single photon emission computed tomography (ISO-SPECT). The findings were compared with those obtained from isoproterenol stress ECG testing (ISO-ECG) and exercise SPECT (EX-SPECT). Isoproterenol was iv injected in a dose of 0.02 ?g/kg/min. The amount was continuously increased until limited by chest pain, ST depression, and/or determined heart rate criteria. The patients were scanned immediately and three hours after giving isoproterenol. Transient hypoperfusion was regarded as myocardial ischemia. Washout rate, obtained from circumferential profile analysis on the short axis SPECT images, was expressed by Bull's eye display. Fifteen patients with angiographically significant stenosis of 75% or greater were diagnosed as having coronary artery disease (CAD). The other five patients had normal coronary artery (NC). In diagnosing CAD, ISO-ECG and ISO-SPECT had a sensitivity of 80% and 92%, respectively. Because the NC group had negative findings for redistribution on ISO-SPECT, the specificy of ISO-SPECT seemed to be high. For multi-vessel disease, redistribution on ISO-SPECT tended to underestimate coronary lesions. The underestimation was, however, corrected by calculating washout rate. For evaluable 11 patients undergoing concurrent EX-SPECT, ISP-SPECT was equivalent or superior to EX-SPECT in diagnostic sensitivity. None of the patients had severe side effects oof the patients had severe side effects of isoproterenol, except for some having arrhythmia. The results indicated that ISO-SPECT is a safe, high sensitive diagnostic approach that is comparable to Ex-SPECT. (N.K.)

  9. Single photon emission computed tomography myocardial imaging: clinical applications and future directions.

    Science.gov (United States)

    Driver, K A; Atchley, A E; Kaul, P; Borges-Neto, S

    2009-06-01

    Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) has proven to be an invaluable tool in the non-invasive assessment of patients with cardiovascular diseases. Exercise and pharmacologic stress SPECT MPI has been extensively studied and validated in the diagnosis and prognosis of patients with known and suspected coronary artery disease. In addition to the assessment of perfusion, electrocardiography-gated SPECT offers additional functional and volumetric information that can have significant implications on patient care. SPECT also has well-developed applications in systolic heart failure for identifying viable myocardium and predicting response to revascularization. Emerging applications of SPECT imaging include: l) phase analysis for quantitative assessment of LV dyssynchrony that may serve to improve patient selection for CRT; 2) application of heart-to-mediastinal ratio via 123I meta-iodobenzylguanidine (I-MIBG) imaging for the prediction of sudden death in patients with reduced left ventricular function, that may serve to improve patient selection for ICD therapy, and 3) use of metabolic tracers to identify the changes of ''ischemic memory'', which may help with rapid and appropriate triage of patients in the emergency room setting. SPECT MPI remains a cornerstone of clinical care that is evolving with emerging and novel applications that will continue to improve the care of patients with cardiovascular disease in the future. PMID:19513013

  10. Serial right ventricle 201Tl imaging after exercise: relation to anatomy of the right coronary artery

    International Nuclear Information System (INIS)

    The relation of the appearance of the right ventricle on serium 201Tl myocardial imaging to coronary artery anatomy was examined in 88 consecutive patients undergoing exercise 201Tl testing and coronary angiography for the evaluation of chest pain. Transient defects in the right ventricle were found in 8 patients. All had high grade (greater than or equal to 90%) stenosis of the proximal right coronary artery. Nonvisualization of right ventricular (RV) activity occurred in 10 patients. Nine of the 10 (90%) had significant (greater than or equal to 50% stenosis) disease of the proximal right coronary artery and 7 (70%) had high grade stenosis. The right ventricle appeared normal in 70 patients. Twenty-nine (41%) of these patients had significant proximal right coronary artery disease. Right ventricular appearance was not affected by the presence or absence of disease of the left anterior descending or left circumflex artery or by the appearance of the left ventricle. Thus, with serial RV thallium-201 myocardial imaging after exercise, we found that (1) RV transient defects suggest the presence of high grade proximal right coronary artery stenosis, (2) non-visualization of RV activity also predicts significant proximal right coronary disease, and (3) the right ventricle frequently appears normal despite proximal right coronary artery disease and therefore this finding does not exclude such disease

  11. Technetium-99m pyrophosphate/thallium-201 dual-isotope SPECT imaging predicts reperfusion injury in patients with acute myocardial infarction after reperfusion

    International Nuclear Information System (INIS)

    Microcirculatory failure after reperfusion is clinically indicated to cause reperfusion injury whereas excessive intracellular calcium ion overload is experimentally proved as a key mechanism of reperfusion injury. We hypothesized that technetium-99m (99mTc) pyrophosphate (Tc-PYP) uptake in injured but viable infarct-related myocardium with preserved myocardial perfusion after reperfusion estimated by thallium-201 (201Tl) uptake would be associated with final functional recovery. Dual-isotope Tc-PYP/201Tl single-photon emission computed tomography (SPECT) was performed 2 days after successful reperfusion therapy in patients with first acute myocardial infarction, and 50 patients (63 ± 13 years old, female 22%) with preserved 201Tl uptakes of ?50% in reperfused myocardium was followed for 1 month. Tc-PYP uptake was assessed as the heart-to-sternum (H/S) ratio. Two-dimensional echocardiography was also performed 2 days and 1 month after reperfusion to evaluate functional recovery. High Tc-PYP uptake, defined as the H/S ratio ?0.81, was predictive of chronic phase no functional recovery (73.7% in 14 of 19 patients with high uptake vs 16.1% in five of 31 patients without those, p 201Tl dual-isotope SPECT imaging can provide prognostic information after reperfusion. (orig.)

  12. Usefulness of lung and right ventricular thallium-201 uptake during single photon emission computed tomography in exercise testing of patients with coronary artery disease

    International Nuclear Information System (INIS)

    Increased pulmonary or right ventricular 201Tl uptake during the exercise test has been used as a marker of multivessel coronary artery disease. The most useful method for assessing the severity of coronary artery disease was evaluated among conventional evaluation of single photon emission computed tomography (SPECT), measurement of lung to heart uptake ratio (L/H), and right ventricular to left ventricular uptake ratio (RV/LV) on 201Tl images during exercise testing. Regions-of-interest (4 x 4 pixels) were placed at the lung and the heart, and L/H was defined as mean lung uptake/mean heart uptake. Correspondingly, regions-of-interest (4 x 4 pixels) were placed at the RV and the LV, and RV/LV was defined as maximum RV uptake/maximum LV uptake. L/H and RV/LV on the initial image were analyzed in 216 patients (angiographically normal coronary arteries: 89, single-vessel disease: 82, multivessel disease: 45). The diagnostic value was evaluated using the receiver operating characteristic curve. All methods showed significantly higher values in patients with multivessel disease than in patients with no coronary artery disease or single-vessel disease. L/H was significantly higher in patients with prior myocardial infarction and RV/LV was significantly higher in patients without infarction. The sensitivity of only conventional SPECT evaluation for multivessel coronary artery disease was low (sensitivity 53%, specificity 94%). However, addition of evalpecificity 94%). However, addition of evaluation of L/H and RV/LV to SPECT improved the sensitivity for multivessel coronary artery disease (sensitivity 93%, specificity 49%). The diagnostic sensitivity for multivessel coronary artery disease was improved by adding L/H and RV/LV to conventional evaluation of exercise 201Tl SPECT. L/H and RV/LV during exercise 201Tl imaging may provide additional information regarding the severity of coronary artery disease. (author)

  13. Transmission-based scatter correction of 180 C myocardial single-photon emission tomography studies

    International Nuclear Information System (INIS)

    Meaningful comparison of single-photon emission tomographic (SPET) reconstructions for data acquired over 180 or 360 can only be performed if both attenuation and scatter correction are applied. Convolution subtraction has appeal as a practical method for scatter correction; however, it is limited to data acquired over 360 . A new algorithm is proposed which can be applied equally well to data acquired over 180 or 360 . The method involves estimating scatter based on knowledge of reconstructed transmission data in combination with a reconstructed estimate of the activity distribution, obtained using attenuation correction with broad beam attenuation coefficients. Processing is implemented for planes of activity parallel to the projection images for which a simplified model for the scatter distribution may be applied, based on the measured attenuation. The appropriate broad beam (effective) attenuation coefficients were determined by considering the scatter buildup equation. It was demonstrated that narrow beam attenuation coefficients should be scaled by 0.75 and 0.65 to provide broad beam attenuation coefficients for technetium-99m and thallium-201 respectively. Using a thorax phantom, quantitative accuracy of the new algorithm was compared with conventional transmission-based convolution subtraction (TDCS) for 360 data. Similar heart to lung contrasts were achieved and correction of 180 data yielded a 10.4% error for cardiac activity compared to 5.2% for TDCS. Contr activity compared to 5.2% for TDCS. Contrast for myocardium to ventricular cavity was similarly good for scatter-corrected 180 and 360 data, in contrast to attenuation-corrected data, where contrast was significantly reduced. The new algorithm provides a practical method for correction of scatter applicable to 180 myocardial SPET. (orig.)

  14. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    International Nuclear Information System (INIS)

    The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiologic and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. A protocol based upon geometrically well defined phantoms was developed. In a mosaic pattern phantom count rates were corrected from 39-43% to 101-110% of reference. In healthy subjects non-gravitational pulmonary perfusion gradients observed without attenuation correction were artefacts caused by attenuation. Pulmonary density in centre of right lung, obtained from the transmission measurement, was 0.28 ± 0.03 g/ml in normal subjects. Mean density was lower in large lungs compared to smaller ones. We also showed that regional ventilation/perfusion ratios could be measured with SPECT, using the readily available tracer 133Xe. Because of the low energy of 133Xe this relies heavily upon attenuation correction. A commercially available system for attenuation correction with simultaneous emission and transmission, considered to improve myocardial SPECT, performed erroneously. This could lead to clinical misjudgement. We considered that manufacturer-independent pre-clinical tests are required. In a test of two other commercial systems, based on different principles, an adapted variant of our initial protocol was proven useful. Only one of the systems provided correct emission count rates independently on phantom configuration. Errors in the other system were related to inadequate compensation of the influence of emission activity on the transmission study

  15. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Almquist, H

    2000-01-01

    The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiologic and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. A protocol based upon geometrically well defined phantoms was developed. In a mosaic pattern phantom count rates were corrected from 39-43% to 101-110% of reference. In healthy subjects non-gravitational pulmonary perfusion gradients observed without attenuation correctionwere artefacts caused by attenuation. Pulmonary density in centre of right lung, obtained from the transmission measurement, was 0.28 {+-} 0.03 g/ml in normal subjects. Mean density was lower in large lungs compared to smaller ones. We also showed that regional ventilation/perfusion ratios could be measured with SPECT, using the readily available tracer {sup 133}Xe. Because of the low energy of {sup 133}Xe this relies heavily upon attenuation correction. A commercially available system for attenuation correction with simultaneous emission and transmission, considered to improve myocardial SPECT, performed erroneously. This could lead to clinical misjudgement. We considered that manufacturer-independent pre-clinical tests are required. In a test of two other commercial systems, based on different principles, an adapted variant of our initial protocol was proven useful. Only one of the systems provided correct emission count rates independently on phantom configuration. Errors in the other system were related to inadequate compensation of the influence of emission activity on the transmission study.

  16. Evaluating image denoising methods in myocardial perfusion single photon emission computed tomography (SPECT) imaging

    International Nuclear Information System (INIS)

    The statistical nature of single photon emission computed tomography (SPECT) imaging, due to the Poisson noise effect, results in the degradation of image quality, especially in the case of lesions of low signal-to-noise ratio (SNR). A variety of well-established single-scale denoising methods applied on projection raw images have been incorporated in SPECT imaging applications, while multi-scale denoising methods with promising performance have been proposed. In this paper, a comparative evaluation study is performed between a multi-scale platelet denoising method and the well-established Butterworth filter applied as a pre- and post-processing step on images reconstructed without and/or with attenuation correction. Quantitative evaluation was carried out employing (i) a cardiac phantom containing two different size cold defects, utilized in two experiments conducted to simulate conditions without and with photon attenuation from myocardial surrounding tissue and (ii) a pilot-verified clinical dataset of 15 patients with ischemic defects. Image noise, defect contrast, SNR and defect contrast-to-noise ratio (CNR) metrics were computed for both phantom and patient defects. In addition, an observer preference study was carried out for the clinical dataset, based on rankings from two nuclear medicine clinicians. Without photon attenuation conditions, denoising by platelet and Butterworth post-processing methods outperformed Butterworth pre-processing for large size defects, while for small size defects, as well as with photon attenuation conditions, all methods have demonstrated similar denoising performance. Under both attenuation conditions, the platelet method showed improved performance with respect to defect contrast, SNR and defect CNR in the case of images reconstructed without attenuation correction, however not statistically significant (p > 0.05). Quantitative as well as preference results obtained from clinical data showed similar performance of the denoising methods studied. In conclusion, the multi-scale platelet denoising method applied on raw projection images provides more efficient noise reduction while preserving image quality in a myocardial phantom SPECT imaging as compared to the Butterworth filter applied either on projection or reconstructed images. However, this trend in favour of the platelet denoising method was not observed on clinical data reconstructed either without or with attenuation correction

  17. Dosimetric consequences of interstitial extravasation following i.v. administration of 201Tl

    International Nuclear Information System (INIS)

    There is a slight possibility that radiopharmaceutical administrations are infiltrated to the subcutaneous tissue at intravenous administration. 201Tl has a long effective half life at subcutaneous tissue. It thus appears that there is some risk for radiation dermatitis when 201Tl is injected subcutaneously. To estimate radiation dose from extravasated 201Tl chloride, we created simple models. An absorbed dose to the basal cell layer of skin because of an inadvertent intravenous injection of 201Tl chloride was calculated from these models. The result indicated that extravasated 201Tl chloride may cause radiation burdens at high specific activity. (author)

  18. Clinical significance of 201Tl reverse redistribution in patients with aorto-coronary bypass surgery

    International Nuclear Information System (INIS)

    Detection of myocardial ischemia by the stress thallium scan has traditionally been performed using transient defect analysis on exercise, followed by redistribution studies. Worsening of the 201Tl myocardial image from exercise to redistribution is referred to as reverse redistribution. In this study, we found reverse redistribution in 10 (21%) of 48 angina pectoris patients who had undergone aortocoronary bypass surgery. The clinical significance of this phenomenon in these patients was investigated in relation to angiographic and surgical findings. Reverse redistribution was found to occur in regions which were supplied by bypass grafts. These areas showed increased coronary blood flow and rapid thallium washout. Our results indicate that a perfusion defect in the bypass region of the redistribution image might be caused by relatively rapid washout in the bypass graft region compared to the adjacent normal myocardium. These results should be considered in the clinical interpretation of stress thallium scans. (orig.)

  19. Selection of methods for determining radiochemical purity of (201Tl) thallous chloride

    International Nuclear Information System (INIS)

    Different kinds of chromatographic and electrophoretic methods for determining (201Tl) thallous chloride and thallic chloride were compared in a same batch of samples. It was found that mono-valent and tri-valent 201Tl ions could be separated by using cellulose acetate-electrophoresis, paper electrophoresis, pre-saturation paper chromatography and non-saturation paper chromatography. Very close results for the amount of mono-valent 201Tl were obtained when (201Tl) thallous chloride samples were used for the determination. However, it was not consistent for tri-valent 201Tl using the four methods described above. The amount of tri-valent 201Tl was determined effectively by the ascending presaturation paper chromatography method using Na2HPO4-acetone (10:90) as developing agent. The method, with advantages of good reproducibility and small error, is there fore recommended for the determination of radiochemical purity of (201Tl) thallous chloride

  20. Comparison of 99mTc-tetrofosmin with 201Tl imaging in the detection of CAD

    International Nuclear Information System (INIS)

    Full text: This prospective study was planned to compare the results of technetium-99m tetrofosmin with thallium-201 imaging in the detection of coronary artery disease (CAD). A total of 25 male patients (mean age : 49.32 y) underwent technetium-99m-tetrofosmin and thallium-201 planar imaging on different days. Each study was divided into 15 segments for analysis. Semiquantitative visual analysis was performed by assigning regional tracer activities in each segment on 4 points scoring system ranging from 0 to 3 with 0 representing normal uptake, 1 - mild, 2 - moderate, 3 - severe reduction in activity. Of the 375 myocardial segments, 355 (94.7%) segments were concordant, of which 276 (77.7%) were normal, 46 (13%) were fixed defects segments and 33 (9.3%) were reversible defects segments. The remaining 20 (5.3) segments were discordant. 99mTc-tetrofosmin shows comparable results with 201Tl in both normal and in patients with non-reversible perfusion defects. This study also shows that 99mTc-tetrofosmin gives better quality images than 201Tl

  1. Utility of 123I-?-methyl iodophenyl pentadecanoic acid (BMIPP) myocardial scintigraphy in the diagnosis of the cardiac involvement in sarcoidosis

    International Nuclear Information System (INIS)

    We evaluated the utility of myocardial scintigraphy using 123I-?-methyl iodophenyl pentadecanoic acid (123I-BMIPP) in the diagnosis of cardiac sarcoidosis. Myocardial single photon emission computed tomographies (SPECT) with 123I-BMIPP and 201Tl were performed in 26 patients with sarcoidosis. Each of basal and mid left ventricular levels of the short axis image of SPECT was divided into 6 segments, and the apical lesion obtained from the long axis image of SPECT was added making 13 segments in all. Then we got the defect score including four steps from normal uptake to defect. We examined the correlation between the defect score of 123I-BMIPP and that of 201Tl. Significant correlations were observed between defect score of 123I-BMIPP and 201Tl. The reduction of uptake in myocardial SPECT with 123I-BMIPP reflects cardiac involvement in the patients with sarcoidosis. The results suggest the usefulness of the myocardial scintigraphy with 123I-BMIPP in the diagnosis of cardiac involvement in sarcoidosis. (author)

  2. Effect of scatter correction on quantification of myocardial SPECT and application to dual-energy acquisition using triple-energy window method

    International Nuclear Information System (INIS)

    Triple-energy window (TEW) method is a simple and practical approach for correcting Compton scatter in single-photon emission tracer studies. The fraction of scatter correction, with a point source or 30 ml-syringe placed under the camera, was measured by the TEW method. The scatter fraction was 55% for 201Tl, 29% for 99mTc and 57% for 123I. Composite energy spectra were generated and separated by the TEW method. Combination of 99mTc and 201Tl was well separated, and 201Tl and 123I were separated within an error of 10%; whereas asymmetric photopeak energy window was necessary for separating 123I and 99mTc. By applying this method to myocardial SPECT study, the effect of scatter elimination was investigated in each myocardial wall by polar map and profile curve analysis. The effect of scatter was higher in the septum and the inferior wall. The count ratio relative to the anterior wall including scatter was 9% higher in 123I, 7-8% higher in 99mTc and 6% higher in 201Tl. Apparent count loss after scatter correction was 30% for 123I, 13% for 99mTc and 38% for 201Tl. Image contrast, as defined myocardium-to-left ventricular cavity count ratio, improved by scatter correction. Since the influence of Compton scatter was significant in cardiac planar and SPECT studies; the degree of scatter fraction should be kept degree of scatter fraction should be kept in mind both in quantification and visual interpretation. (author)

  3. The value of 201Tl SPECT and MRI in evaluating malignancy of gliomas: a comparative study

    International Nuclear Information System (INIS)

    Purpose: To evaluate the value of 201Tl SPECT and enhanced MRI in classification of gliomas. Methods: With semiquantitative method, the authors compared 201Tl uptake and MRI enhancement in classification of gliomas in 37 patients with histologically confirmed supratentorial glioma, including 13 low-grade gliomas (LgG), 8 anaplastic gliomas (AG) and 16 glioblastomas (GB) according to WHO classification. Results: The 201Tl uptake were 1.23 +- 0.76 in LgG, 2.60 +- 1.24 in AG, and 4.45 +- 1.68 in GB. LgG had a significantly lower uptake than AG and GB (P201Tl SPECT. Moreover, the present study showed that a moderate MRI enhancement was not accurate enough in classification of gliomas, and 201Tl SPECT could offer complementary information. Conclusions: 201Tl SPECT is more valuable for evaluating malignancy of the gliomas than MRI

  4. Single photon radionuclide computed tomography with Tomogscanner II, (1)

    International Nuclear Information System (INIS)

    The single photon radionuclide computed tomography (RCT) was examined in 214 patients with the Tomogscanner-II. The RCT of brain was superior to the conventional brain scan, especially in the detection of lesions at the base of brain or the postoperated condition. The blood pool RCT of brain depicted an arterio-venous malformation and a giant aneurysma at the base of brain. The RCT of cisternography was useful to understand the anatomical relationship of the activity. The RCT of cerebral blood perfusion was possible with a method of continuous infusion of sup(81m)Kr into an internal carotid artery. In the body study, the reconstructed image of the Tomogscanner was excellent. The area of myocardial infarction showed clear defect in the horse-shaped myocardial section image after injection of 4 mCi of 201TlCl. The RCT of liver was available to detect defects and evaluated the activity and size of spleen. The RCT of kidney, lung or bone also showed good image, respectively. The Tomogscanner-II gave very good images in clinical examination of body as well as brain. (author)

  5. Role of myocardial perfusion single photon emission computed tomography in pediatric cardiology practice

    Directory of Open Access Journals (Sweden)

    Sundaram P

    2009-01-01

    Full Text Available Diagnostic and prognostic power of myocardial perfusion imaging in patients with coronary artery disease has been demonstrated with planar imaging which was further improvised with addition of gated SPECT and newer Technetium labeled myocardial perfusion tracers like SestaMIBI, Tetrofosmin. Myocardial perfusion abnormalities at rest and after stress are considered to be the best predictors of cardiac event-free survival in adults with ischemic heart disease. This article highlights various myocardial perfusion imaging (MPIradiopharmaceuticals, exercise procedures, pharmacological stress protocols, indications for MPI and myocardial perfusion patterns in children with some of the common congenital and acquired heart diseases.

  6. Role of myocardial perfusion single photon emission computed tomography in pediatric cardiology practice

    International Nuclear Information System (INIS)

    Diagnostic and prognostic power of myocardial perfusion imaging in patients with coronary artery disease has been demonstrated with planar imaging which was further improvised with addition of gated SPECT and newer Technetium labeled myocardial perfusion tracers like SestaMIBI, Tetrofosmin. Myocardial perfusion abnormalities at rest and after stress are considered to be the best predictors of cardiac event–free survival in adults with ischemic heart disease. This article highlights various myocardial perfusion imaging (MPI) radiopharmaceuticals, exercise procedures, pharmacological stress protocols, indications for MPI and myocardial perfusion patterns in children with some of the common congenital and acquired heart diseases

  7. 201Tl scintigraphy in postoperative detection of thyroid cancer: a comparative study with 131I

    International Nuclear Information System (INIS)

    201Tl scintigraphy was performed to visualize malignant lesions postoperatively in 28 patients with thyroid cancer. The results were compared with those of 131I and/or /sup 99m/Tc pertechnetate scintigraphy. Of eight patients who had malignant lesions and no normal thyroid tissue, 201Tl concentration was observed in seven, while 131I concentration was observed in only three. All of four patients who had malignant lesions and did have remaining normal thyroid tissue showed concentrations of 201Tl. 201Tl scintigraphy can be performed without any preparation and may be useful in depicting residual and recurrent lesions regardless of the presence of normal thyroid tissue

  8. Role of myocardial perfusion single photon emission computed tomography in pediatric cardiology practice

    OpenAIRE

    Sundaram P; Padma S

    2009-01-01

    Diagnostic and prognostic power of myocardial perfusion imaging in patients with coronary artery disease has been demonstrated with planar imaging which was further improvised with addition of gated SPECT and newer Technetium labeled myocardial perfusion tracers like SestaMIBI, Tetrofosmin. Myocardial perfusion abnormalities at rest and after stress are considered to be the best predictors of cardiac event–free survival in adults with ischemic heart disease. This article highlights various ...

  9. The role of thallium-201 single photon emission tomography in the investigation and characterisation of brain tumours in man and their response to treatment

    International Nuclear Information System (INIS)

    The aim of this study was to characterise brain tumour type and treatment response in relation to the uptake of thallium-201. 201Tl single photon emission tomography (SPET) was performed in 58 patients with brain tumours. Fifty-six patients were utilised for the statistical comparison of the early and delayed 201Tl indices expressed as the ratio of tumour to contralateral cerebral hemisphere uptake. The retention index of 201Tl in the tumour tissue calculated from the early and delayed scans was also analysed. Furthermore, in 56 patients with 58 brain tumours, a comparison was made of the diagnostic value of high 201Tl uptake and gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) enhancement on MRI scans. Although high 201Tl uptake was observed in viable malignant gliomas, brain metastases, meningiomas and malignant teratoma, the viable malignant gliomas could not be differentiated from brain metastases and extracerebral tumours by means of 201Tl indices. 201Tl SPET failed to diagnose a viable ring-enhanced tumour with a thin rim and small tumours of less than 1.5 cm in diameter visualised by Gd-DTPA-enhanced MRI. In spite of this, 201Tl SPET appears to be effective for determination of the malignant viability of tumours. (orig.)

  10. Quantitative evaluation of intermittent claudication by 201Tl perfusion scintigraphy

    International Nuclear Information System (INIS)

    Present attempt was to define intermittent claudication objectively by quantitative assessment of 201Tl perfusion scintigraphy of leg both at rest and exercise loading. After intravenous injection of 201Tl with or without exercise loading by treadmil the distribution of this tracer throughout body was obtained using a whole body scanner. According to the indicator fractionation principle, regional blood flow of cardiac output (rBF/co) for each segment of the legs was expressed as a fractional deposited radioactivity (rFU) at these segments of that of whole body. Validity of the principle was confirmed by comparing the deposited activity of 201Tl with that of sup(99m)Tc-MMA and a good correlation was found (r = 0.979). rFU in normals was 5.49 x 0.69% (total leg) 3.57 x 0.49% (thigh) and 1.59 x 0.34% (calf) at rest and 19.40 x 2.04% (total leg) 12.26 x 1.91% (thigh) and 6.58 x 0.99% (calf) during exercise. The change ration from the rest to the exercise (?rFU) was 3.41 x 0.45 (total leg) 3.44 x 0.61 (thigh) and 4.30 x 1.30 (calf). In patient with known ASO and TAO rFU was within normal range at rest but duing exercise ?rFU was significantly less than that of normal (1.95 x 0.40 in the total leg of ASO p < 0.001; 1.82 x 0.47 in the total leg of TAO p < 0.001). A defect or decreased activity on the stress scintigraphy of the legs was wall correlated with the angiographic findings. (author)

  11. Technetium-99m sestamibi and tetrofosmin myocardial single-photon emission tomography: can we use the same reference data base?

    International Nuclear Information System (INIS)

    The aim of this study was to compare technetium-99m labelled tetrofosmin and sestamibi myocardial perfusion single-photon emission tomography (SPET) with one common sestamibi reference file for bull's eye imaging, with quantitation of the extent and severity of perfusion defects. Twenty patients suspected or known to have coronary artery disease participated in the study. Patients first underwent routine sestamibi myocardial SPET over 2 days, receiving doses of 400-600 MBq at stress and 600-800 MBq at rest. Then within the same week a 1-day tetrofosmin myocardial SPET study was performed, with a dose of 300 MBq at stress, followed 2.5 h later by a dose of 750 MBq at rest. Bull's eye images were generated for visual evaluation. Black-out defects according to the Cequal software analysis were only recorded if they comprised more than 10 pixels in men and 20 in women. According to the Cequal program, extent score and severity scores were expressed as number of pixels and deviations below reference limits. Five patients had normal myocardial SPET imaging with both radiotracers, while 15 had reversible, irreversible or partially reversible defects. The concordance of the results was high. The only two significant differences were that one patient had a reversible defect which appeared to be located in different myocardial regions (LAD vs RCA), and another patient had a defect that was partially reversible with sestamibi but irreversible with tetrofosmin. The results showedsible with tetrofosmin. The results showed very high correlation coefficients for the extent and severity scores (linear correlation coefficient values of 0.99 and 0.94, respectively). In conclusion, it appears that changing between sestamibi and tetrofosmin has little influence on the interpretation of bull's eye images from the data file of a common reference population using one of the tracers. (orig.). With 3 figs., 3 tabs

  12. Technetium-99m sestamibi single-photon emission tomography detects subclinical myocardial perfusion abnormalities in patients with systemic lupus erythematosus

    International Nuclear Information System (INIS)

    In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with 99mTc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images (''reverse redistribution pattern''). Coronary angiography was performed in eight patients with positive 99mTc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that 99mTc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole 99mTc-sestamibi SPET can be a useful non-invasive method to identify subclinical myonvasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events. (orig.)

  13. Technetium-99m sestamibi single-photon emission tomography detects subclinical myocardial perfusion abnormalities in patients with systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Schillaci, O. [Nuclear Medicine, University of l`Aquila (Italy); Lagana, B.; Gentile, R.; Tubani, L.; Baratta, L. [Department of Clinical Medicine, University ``La Sapienza``, Rome (Italy); Danieli, R.; Scopinaro, F. [Section of Nuclear Medicine, Department of Experimental Medicine and Pathology, University ``La Sapienza``, Rome (Italy)

    1999-07-01

    In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with {sup 99m}Tc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images (``reverse redistribution pattern``). Coronary angiography was performed in eight patients with positive {sup 99m}Tc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that {sup 99m}Tc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole {sup 99m}Tc-sestamibi SPET can be a useful non-invasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events. (orig.) With 2 figs., 2 tabs., 21 refs.

  14. Assessment of regional myocardial uptake and metabolism of #betta#-(p-123I-phenyl) pentadecanoic acid with serial single-photon emission tomography

    International Nuclear Information System (INIS)

    The utility of myocardial imaging and assessment of regional myocardial metabolism of #betta#-(123I-paraphenyl-)pentadecanoic acid (I-PPA) by means of serial single-photon tomography is demonstrated in animal experiments. High quality cross sectional images of dog hearts with clear delineation of left ventricular walls are obtained. Myocardial infarcts are visualized as areas of deficient radioactivity uptake. I-PPA elimination from non-infarcted myocardial regions is significantly (p < 0.001) prolonged when compared with unaffected controls. Hence, not only localized absence of uptake of free fatty acid by infarcted myocardium can be demonstrated with serial single-photon tomography but also general impairment of cardiac FFA-metabolism. (orig.)

  15. Recovery of 201Tl by ion exchange chromatography from proton bombarded thallium cyclotron targets

    International Nuclear Information System (INIS)

    A method based on ion exchange chromatography is presented for the recovery of 201Tl and its precursor 201Pb from proton bombarded natural thallium cyclotron targets. After bombardment the target is dissolved in diluted nitric acid. Water, hydrazine and ammonium acetate are added to the solution and the lead radioisotopes separated from the thallium by cation exchange chromatography on a Bio-Rex 70 column. The sorbed lead radioisotopes are eluted with dilute nitric acid and the separation repeated on a second Bio-Rex 70 column. After elution of the remaining thallium the column is left for 32 hours and the 201Tl formed by decay of 201Pb is eluted with an ammonium acetate solution. The 201Tl eluate is acidified with a HNO3-HBr-Br2 mixture and the resulting solution is passed through an AG MP-1 anion exchanger column to remove any remaining lead isotopes. The 201Tl is eluted with a hydrazine solution, the eluate evaporated to dryness and the 201Tl finally dissolved in an appropriate solution to produce a 201TlCl solution suitable for medical use. A high quality 201Tl product is obtained containing ? 0.1 ?g of Tl/mCi (37 MBq) 201Tl. The radionuclidic impurities are less than the maximum values specified by the US Pharmacopoeia and the British Pharmacopoeia. (orig.)

  16. Re-evaluation of clinical value of 201Tl thyroid scintigraphy for nodular goiter

    International Nuclear Information System (INIS)

    To investigate the utility of 201Tl scintigraphy for the diagnosis of nodular goiter early (E) and delayed (D) scintigraphy was done in 65 patients with 87 lesions. The detectable minimum caliber of nodule was 1.0 cm of papillary cancer in isthmus. 201Tl accumulation and 201Tl accumulation patterns (E(+) D(+) and E(+) D(-)) in thyroid nodules showed no correlation with tumor size and tumor location. E(+) D(+) pattern which shows a slow tumor washout of 201Tl was observed in 66% of papillary cancers, 100% of follicular cancers, 100% of malignant lymphomas and 42% of follicular adenomas. When the diagnostic criteria of malignant thyroid tumor was E(+) D(+) pattern on scintigram, sensitivity was 74%, specificity was 74% and accuracy was 72%. Chronic thyroiditis was not an influential factor to delay the washout of 201Tl on scintigram. From this study we can conclude that 201Tl scintigraphy is not highly accurate for the diagnosis of nodular goiter. However, the mechanism of 201Tl accumulation in a thyroid tumor depends on rapidly increasing growth rate of tumor. Thus, 201Tl scintigraphy may be helpful to determine indication for surgery. (author)

  17. Reverse redistribution phenomenon on rest 99mTc-tetrofosmin myocardial single photon emission computed tomography involves impaired left ventricular contraction in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    The purpose of this study was to investigate the clinical significance of the reverse redistribution (RR) phenomenon on technetium-99m (99mTc)-tetrofosmin myocardial single photon emission computed tomography (SPECT) performed at rest. Twenty-five patients underwent myocardial SPECT 3 weeks after the onset of acute myocardial infarction. Myocardial images were acquired at 40 min (early) and 4 h (delayed) after the injection of 740 MBq of 99mTc-tetrofosmin. The regional myocardial uptake of the tracer in 26 segments of the left ventricular (LV) wall was visually scored from 0 (no activity) to 3 (normal activity), and then the RR was defined as a decrease of more than 1 point in the activity score on the delayed image compared with that on the early image. Regions with an activity score of 3 on both the early and delayed images were defined as normal, and those with a score of 0 or 1 on the early image were considered to have a fixed defect. The regional myocardial 99mTc-tetrofosmin uptake and washout rate were also quantitatively assessed in each region. In addition, exercise stress electrocardiograph-gated SPECT with 99mTc-tetrofosmin was performed within 1 week of the rest study, and the percent count increase (%CI) during myocardial contraction in each corresponding region was studied. RR was observed in 18 of the 25 patients. The regional washout rate of 99mTc-tetrofosmin was significantly higher in the RR regiin was significantly higher in the RR regions (45.0±3.8%) than in either the normal regions (36.4±4.1%, p99mTc-tetrofosmin SPECT have severely impaired LV wall contraction after exercise. (author)

  18. Quantitative assessment of myocardial viability following coronary artery bypass grafting using exercise thallium-201 myocardial single photon emission computed tomography and left ventricular regional wall motion

    International Nuclear Information System (INIS)

    Using exercise thallium-201 myocardial single photon emission computed tomography (SPECT) and % radial shortening (%RS), 58 patients were evaluated before and after coronary artery bypass grafting (CABG) to quantitatively assess myocardial viability and the effect of CABG. The patient was classified, according to redistribution pattern, as group I with only complete redistribution (20 cases) and group II with including incomplete redistribution (22 cases) and group III with no redistribution (16 cases). Group I was expected complete improvement of ischemic myocardium after CABG but regional left ventricular wall motion was unchanged (?i%RS: 142.5±54.7?138.4±39.6, ?a%RS: 201.2±51.1?238.2±68.2). Group II was expected to diminish ischemic size after CABG and left ventricular regional wall motion was significantly improved (?i%RS: 68.8±25.9?154.9±42.6 p<0.01, ?a%RS: 108.4±62.3?178.9±77.6, p<0.05). Group III was no significant change of ischemic size and left ventricular wall motion after CABG (?i%RS: 67.8±24.1?83.9±19.2, ?a%RS: 86.0±29.0?94.0±33.9). The present study suggests that quantitative assessment of myocardial viability using exercise thallium-201 myocardial SPECT and %radial shortening was useful method to determine the indication and to assess the effect of CABG. (author)

  19. Rest-redistribution thallium-201 SPECT to detect myocardial viability.

    OpenAIRE

    BISI, Gianni

    1998-01-01

    Rest-redistribution 201Tl imaging is currently being used for myocardial viability detection, but the ideal parameters for territory classification have not yet been defined. The aim of this study was to define the optimal criteria for detecting viable myocardium and predicting postrevascularization recovery with rest-redistribution 201Tl SPECT. METHODS: In 29 patients with left ventricular dysfunction, tracer activity within asynergic segments was quantified on rest and redistribution 201Tl ...

  20. Single photon emission computed tomography of technetium-99m tetrofosmin myocardial perfusion imaging in patients with systemic lupus erythematosus-A preliminary report

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the utility of single-photon emission computed tomography (SPECT) of technetium-99m tetrofosmin (Tc-99m TF) myocardial perfusion imaging to detect myocardial involvement in patients with systemic lupus erythematosus (SLE). Three groups of subjects-group 1: 25 SLE female patients with non-specific cardiac symptoms and signs, group 2: 25 female SLE patients without any cardiac symptoms and signs, and group 3: 25 female healthy controls-were evaluated by comparing rest and dipyridamole-stress Tc-99m TF myocardial perfusion SPECT. Tc-99m TF myocardial perfusion SPECT revealed perfusion defects in 88% and 40% of the cases in groups 1 and 2, respectively. However, no cases in group 3 demonstrated myocardial perfusion defects. Tc-99m TF myocardial perfusion SPECT is a useful noninvasive imaging modality to detect cardiac involvement in SLE patients with or without cardiac symptoms and signs. (author)

  1. Single photon emission computed tomography of technetium-99m tetrofosmin myocardial perfusion imaging in patients with systemic lupus erythematosus-A preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jen-Jhy; Hsu, Hsiu-Bao; Sun, Shung-Shung; Kao, Chia-Hung [China Medical Coll., Taichung, Taiwan (China). Hospital; Wang, Jhi-Joung [Chi-Mei Medical Center, Tainan, Taiwan (China); Ho, Shung-Tai [National Defense Medical Center, Taipei, Taiwan (China). School of Medicine

    2003-01-01

    The purpose of this study was to evaluate the utility of single-photon emission computed tomography (SPECT) of technetium-99m tetrofosmin (Tc-99m TF) myocardial perfusion imaging to detect myocardial involvement in patients with systemic lupus erythematosus (SLE). Three groups of subjects-group 1: 25 SLE female patients with non-specific cardiac symptoms and signs, group 2: 25 female SLE patients without any cardiac symptoms and signs, and group 3: 25 female healthy controls-were evaluated by comparing rest and dipyridamole-stress Tc-99m TF myocardial perfusion SPECT. Tc-99m TF myocardial perfusion SPECT revealed perfusion defects in 88% and 40% of the cases in groups 1 and 2, respectively. However, no cases in group 3 demonstrated myocardial perfusion defects. Tc-99m TF myocardial perfusion SPECT is a useful noninvasive imaging modality to detect cardiac involvement in SLE patients with or without cardiac symptoms and signs. (author)

  2. Impact of Co-morbidity on the Risk of First-Time Myocardial Infarction, Stroke, or Death After Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging

    DEFF Research Database (Denmark)

    Schelde, Astrid Blicher; Schmidt, Morten

    2014-01-01

    The impact of co-morbidity on the cardiovascular risk after single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI) remains unclear. We examined the association between a normal versus abnormal SPECT MPI scan on 10-year risk of myocardial infarction, stroke, and all-cause death, overall and according to co-morbidity level. We identified all patients without previous myocardial infarction or cerebrovascular disease, who had an SPECT MPI performed at Aarhus University Hospital Skejby during 1999 to 2011. We categorized the SPECT MPI scan as normal (no defects) or abnormal (reversible and/or fixed defects). Using nationwide medical registries, we obtained information on co-morbidity level (using Charlson co-morbidity index) and outcomes. We used Cox regression to compute hazard ratios with 95% confidence intervals (CIs), adjusting for gender, age, and co-morbidity level. Among 7,040 patients, 4,962 (70%) had normal scans and 2,078 (30%) abnormal scans. Patients with a normal versus abnormal scan had a 10-year risk of 5.7% versus 10.9% for myocardial infarction, 6.0% versus 7.8% for stroke, and 16.5% versus 29.0% for all-cause death. After adjustment, an abnormal scan was associated with increased risk of myocardial infarction (adjusted hazard ratio 1.73, 95% CI 1.37 to 2.18) and all-cause death (1.42, 95% CI 1.23 to 1.65) but not stroke (1.12, 95% CI 0.86 to 1.45). Co-morbidity level did not affect substantially the association between the scan result and the outcomes. In conclusion, independently of co-morbidity level, an abnormal SPECT MPI scan was associated with an increased 10-year risk of myocardial infarction and all-cause death but not stroke.

  3. Iodine-123-labelled fatty acids for myocardial single-photon emission tomography: current status and future perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, F.F. Jr. [Nuclear Medicine Group, Health Sciences Research Div., Oak Ridge National Lab. (ORNL), TN (United States); Kropp, J. [Klinik und Poliklinik fuer Nuklearmedizin des Universitaetsklinikums der Technischen Univ., Dresden (Germany)

    1995-04-01

    Renewed interest in the clinical use of iodine-123-labelled fatty acids is currently primarily focused on the use of iodine-123-labelled 15-(p-iodophenyl)pentadecanoic acid (IPPA) and ``modified`` fatty acid analogues such as 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) which show delayed myocardial clearance, thus permitting single-photon emission tomographic imaging. Interest in the use of BMIPP and similar agents results from the differences which have often been observed in various types of heart disease between regional myocardial uptake patterns of [{sup 123}I]BMIPP and flow tracer distribution. Although the physiological basis is not completely understood, differences between regional fatty acid and flow tracer distribution may reflect alterations in important parameters of metabolism which can be useful for patient management or therapy planning. These tracers may also represent unique metabolic probes for correlation of energy substrate metabolism with regional myocardial viability. The two agents currently most widely used clinically are {sup 123}I-labelled IPPA and BMIPP. While [{sup 123}I]IPPA is commercially available as a radiopharmaceutical in Europe (Cygne) and Canada (Nordion), multicenter trials are in progress in the United States as a prelude to approval for broad use. [{sup 123}I]BMIPP was recently introduced as Cardiodine for commercial distribution in Japan (Nihon Medi-Physics, Inc.). [{sup 123}I]BMIPP is also being used in clinical studies on an institutional approval basis at several institutions in Europe and the United States. In this review, the development of a variety of radioiodinated fatty acids is discussed. The results of clinical trials with [{sup 123}I]IPPA and [{sup 123}I]BMIPP are discussed in detail, as are the future prospects for fatty acid imaging. (orig.)

  4. Iodine-123-labelled fatty acids for myocardial single-photon emission tomography: current status and future perspectives

    International Nuclear Information System (INIS)

    Renewed interest in the clinical use of iodine-123-labelled fatty acids is currently primarily focused on the use of iodine-123-labelled 15-(p-iodophenyl)pentadecanoic acid (IPPA) and ''modified'' fatty acid analogues such as 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) which show delayed myocardial clearance, thus permitting single-photon emission tomographic imaging. Interest in the use of BMIPP and similar agents results from the differences which have often been observed in various types of heart disease between regional myocardial uptake patterns of [123I]BMIPP and flow tracer distribution. Although the physiological basis is not completely understood, differences between regional fatty acid and flow tracer distribution may reflect alterations in important parameters of metabolism which can be useful for patient management or therapy planning. These tracers may also represent unique metabolic probes for correlation of energy substrate metabolism with regional myocardial viability. The two agents currently most widely used clinically are 123I-labelled IPPA and BMIPP. While [123I]IPPA is commercially available as a radiopharmaceutical in Europe (Cygne) and Canada (Nordion), multicenter trials are in progress in the United States as a prelude to approval for broad use. [123I]BMIPP was recently introduced as Cardiodine for commercial distribution in Japan (Nihon Medi-Physics, Inc.). [123I]BMIPP is alssics, Inc.). [123I]BMIPP is also being used in clinical studies on an institutional approval basis at several institutions in Europe and the United States. In this review, the development of a variety of radioiodinated fatty acids is discussed. The results of clinical trials with [123I]IPPA and [123I]BMIPP are discussed in detail, as are the future prospects for fatty acid imaging. (orig.)

  5. Iodine-123-labelled fatty acids for myocardial single-photon emission tomography: current status and future perspectives.

    Science.gov (United States)

    Knapp, F F; Kropp, J

    1995-04-01

    Renewed interest in the clinical use of iodine-123-labelled fatty acids is currently primarily focused on the use of iodine-123-labelled 15-(p-iodophenyl)pentadecanoic acid (IPPA) and "modified" fatty acid analogues such as 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) which show delayed myocardial clearance, thus permitting single-photon emission tomographic imaging. Interest in the use of BMIPP and similar agents results from the differences which have often been observed in various types of heart disease between regional myocardial uptake patterns of [123I]BMIPP and flow tracer distribution. Although the physiological basis is not completely understood, differences between regional fatty acid and flow tracer distribution may reflect alterations in important parameters of metabolism which can be useful for patient management or therapy planning. These tracers may also represent unique metabolic probes for correlation of energy substrate metabolism with regional myocardial viability. The two agents currently most widely used clinically are 123I-labelled IPPA and BMIPP. While [123I]IPPA is commercially available as a radiopharmaceutical in Europe (Cygne) and Canada (Nordion), multicenter trials are in progress in the United States as a prelude to approval for broad use. [123I]BMIPP was recently introduced as Cardiodine for commercial distribution in Japan (Nihon Medi-Physics, Inc.). [123I]BMIPP is also being used in clinical studies on an institutional approval basis at several institutions in Europe and the United States. In this review, the development of a variety of radioiodinated fatty acids is discussed. The results of clinical trials with [123I]IPPA and [123I]BMIPP are discussed in detail, as are the future prospects for fatty acid imaging. PMID:7607269

  6. Evaluation of dilated cardiomyopathy by stress Tl-201 myocardial single photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    Stress Tl-201 myocardial SPECT was performed in 20 dilated cardiomyopathy (DCM) and 23 old myocardial infarction (OMI: ED volume ? 200 ml by left ventriculography = LVG) for non-invasive diagnosis of DCM. We assessed the perfusion abnormality of 5 segments (anterior-anterolateral, septal, apical, posterolateral, postero-inferior) in SPECT images in grades as follows; 0: normal, 1: mild low uptake, 2: severe low uptake, 3: complete defect. Thus, we defined the abnormal perfusion score (APS) as the summation of the grades in 5 segments. 1) Perfusion abnormality was found 85 % in DCM and 100 % in OMI by stress SPECT images. 2) Rare complete defect, abnormal perfusion segments under 3 and APS under 7 were characteristic findings in DCM, and could finally distinguish DCM from OMI with the finding of APS under 7 (18/20: 90 %) in stress images. 3) The perfusion abnormality in delayed images had a good relation with wall motion abnormality in OMI, but not DCM. 4) Redistribution was found only 3 cases with DCM (15 %) and 9 cases with OMI (39 %), but mild without 2 cases with OMI. 5) Inspite of exercise induced severe symptom and arrhythmia in some DCM cases, stress SPECT was efficient especially to rule out ischemic heart disease. Thus, we conclude that stress Tl-201 myocardial SPECT is useful method for the non-invasive differential diagnosis of DCM from ischemic heart disease, but wall motion abnormality has no good relation with perfusion abnormality. (author)

  7. Cyclotron production of Thallium-201 via the 205Tl(p,5n)201Pb ? 201Tl reaction

    International Nuclear Information System (INIS)

    The production of the clinically useful 201Tl radioisotope was investigated based upon the utilization of the 205Tl(p,5n)201Pb ? 201Tl reaction. Thin-stacked metallic foils of 99.5% enriched 205Tl were used as targets. Thick-target yields for the daughters 201Tl, 200Tl, and 202Tl were calculated as a function of target thickness, bombarding time, target chemistry time, and incident proton energies. The results demonstrated the feasibility of utilizing the (p,5n) reaction to produce 201Tl of similar radionuclidic composition and in yields comparable to the 203Tl(p,3n)201Pb ? 201Tl method

  8. Leg arteritis exploration by quantitative muscle scintigraphy with 201Tl

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J.; Thouvenot, P.; Schmidt, C.; Escanye, J.M.; Schmitt, J.

    1984-10-01

    Detection and localization of peripheral arterial disease was evaluated by an intravenous injection of 201Tl at peak exercise in 18 subjects and at rest in 6 patients. Images of the skull (S), thighs (T), knees (K), calves (C) and feet (F) were obtained at rest or after exercise and stored in a computer. Intraleg (T/K, T/C, T/F), and left to right interleg (TL/TR,...) count ratios were calculated. In addition, all patients were submitted to routine functional tests (walk perimeter, serial local arterial blood pressure measurement, Strandness test, venous occlusion plethysmography). Correlations between functional tests and the intra and interleg ratios were calculated. After exercise, there is a medium correlation between the tissular blood flow under hyperemia at the calf level and the T/C and C/K ratios. At the calf level a good correlation is obtained for CL/CR and the flux under hyperemia (r = 0.81, P 0.001). A ratio between the counting rates of limb segments after exercise and those of skull was established. The ratios T/S and C/S compared with the systolic pressure index of the most affected limb after a Strandness test give a correlation of 0.72 (P 0.02) for the thigh and of 0.86 (P 0.001) for the calf. For hyperemic flux, the correlation are 0.58 (P 0.005) with T/S and 0.75 (P 0.001) with C/S. In order to find the best quantitative scintigraphic index of the arterial illness, we compared the different ratio values with the distance walked. For T/S we found a relationship very close to a linear one and for C/S a less significant exponential one. Thus, quantitative scintigraphy using 201Tl appears as an accurate method to measure local muscular perfusion deficit in the cases of lower limb arterial disease.

  9. Leg arteritis exploration by quantitative muscle scintigraphy with 201Tl

    International Nuclear Information System (INIS)

    Detection and localization of peripheral arterial disease was evaluated by an intravenous injection of 201Tl at peak exercise in 18 subjects and at rest in 6 patients. Images of the skull (S), thighs (T), knees (K), calves (C) and feet (F) were obtained at rest or after exercise and stored in a computer. Intraleg (T/K, T/C, T/F), and left to right interleg (TL/TR,...) count ratios were calculated. In addition, all patients were submitted to routine functional tests (walk perimeter, serial local arterial blood pressure measurement, Strandness test, venous occlusion plethysmography). Correlations between functional tests and the intra and interleg ratios were calculated. After exercise, there is a medium correlation between the tissular blood flow under hyperemia at the calf level and the T/C and C/K ratios. At the calf level a good correlation is obtained for CL/CR and the flux under hyperemia (r = 0.81, P 0.001). A ratio between the counting rates of limb segments after exercise and those of skull was established. The ratios T/S and C/S compared with the systolic pressure index of the most affected limb after a Strandness test give a correlation of 0.72 (P 0.02) for the thigh and of 0.86 (P 0.001) for the calf. For hyperemic flux, the correlation are 0.58 (P 0.005) with T/S and 0.75 (P 0.001) with C/S. In order to find the best quantitative scintigraphic index of the arterial illness, we compared the different ratio values with the distance walked. For T/S we found a relationship very close to a linear one and for C/S a less significant exponential one. Thus, quantitative scintigraphy using 201Tl appears as an accurate method to measure local muscular perfusion deficit in the cases of lower limb arterial disease

  10. Clinical usefulness of 201Tl-chloride scintigraphy for the diagnosis of bone metastases

    International Nuclear Information System (INIS)

    Fifty-five patients with bone lesions underwent 201Tl-chloride (201Tl) scintigraphy to evaluate its findings and usefulness for the diagnosis of bone metastases. 201Tl scintigraphy was performed 15 minutes (early scan) and 2 hour (delayed scan) after iv injection of 5.55 MBq/kg of 201Tl-chloride. To evaluate the degree of tracer retention at the lesions, we calculated retention index after setting regions of interest in each lesion demonstrated tracer uptake in both early and delayed scans. Among 118 pathologically and/or clinically comfirmed bone metastases, 201Tl planar images disclosed 90 (76.3%) and 88 (74.6%) lesions on early and delayed scans, respectively. SPECT images were preferable for the evaluation of the lesions in the spine, thoracic cage and pelvis. Correlation of tumor size with findings on 201Tl images demonstrated 90.5% sensitivity for the metastases more than 7 cm3. No correlational difference was seen in the sensitivity depending on primary cancers. The overall retention index of bone metastases was -21.4±47.1. Bone metastases of pulmonary adenocarcinomas and small cell carcinomas demonstrated higher retention index than pulmonary squamous cell carcinomas and breast cancers. On 201Tl images, no abnormal tracer uptake was seen in benign lesions detected by 99mTc-hydroxymethylene diphosphonate (99mTc-HMDP) images except 5 lesions. The retentHMDP) images except 5 lesions. The retention index of the benign lesions demonstrated abnormal uptakes of -48.3±15.9 on 201Tl images, showing no significant difference between that of metastases. For vertebral compression fractures, abnormal tracer uptakes were demonstrated in 9 of the 12 pathologic fractures against 2 of the 10 benign ones. Those 2 benign fractures proved to be vertebral tuberculosis. The results suggest 201Tl scintigraphy can find out false positive lesions of 99mTc-HMDP scintigraphy and contribute to diagnosis of bone metastases with combination of other images. (author)

  11. The evaluation of 201TlCl and delayed scan for thyroid imaging agent

    International Nuclear Information System (INIS)

    The results of 189 patients with nodular goiter by imaging with 201TlCl following with sup(99m)TcO4- was presented. Accumulation of 201TlCl to the corresponding area was observed in 85.5% of cancer, 62.2% of adenoma, 42.5% of adenomatous goiter, and the usefulness of 201TlCl (early scan) for thyroid imaging agent was recognized. On the other hand, delayed scan for purpose of differentiation from benign to malignant was also performed. However, no significant differences were obtained. (author)

  12. Myocardial sestamibi single-photon emission tomography: variations in reference values with gender, age and rest versus stress?

    International Nuclear Information System (INIS)

    Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise 99mTc-sestamibi SPET with a 2-day protocol and 180 elliptical rotation. The normalized activity values of 99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in 99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. (orig.). With 3 figs., 3 tabs

  13. Dual radionuclide single-photon emission computed tomography in the prediction of further ischemic risk after acute myocardial infarction

    International Nuclear Information System (INIS)

    To evaluate whether the findings of dual single-photon emission computed tomography (SPECT) with technetium-99m pyrophosphate (Tc-99m PPi) and thallium-201 were predictive of further cardiac events in their hospital course, we studied 130 patients recovering from acute myocardial infarction (AMI). Fifty-four patients showed overlapping of Tc-99m PPi and thallium-201 in the same location (overlap positive group), and 76 patients had no overlap (overlap negative group). Of the 130 patients, 36 (28%) had a cardiac event. In patients in the overlap positive group, the incidence of subsequent events was significantly higher than in patients in the overlap negative group (44% versus 16%; p<0.001). In the overlap positive group, the Tc-99m PPi uptake score and the number of overlap segments in patients with further events was significantly higher than those in patients without further events (10.2±5.1 versus 6.4±4.1, p<0.005 and 5.2±2.0 versus 3.3±1.3, p<0.001, respectively). These results suggest that patients who have a Tc-99m PPi and thallium-201 overlap negative scan can be candidates for early hospital discharge. In contrast, patients who have a greater number of overlap segments may require early catheterization and revascularization, so that simultaneous SPECT imaging Tc-99m PPi and thallium-201 might be useful for identifying patients with further ischemic risk after AMI in their hospital course. (author)

  14. Dual radionuclide single-photon emission computed tomography in the prediction of further ischemic risk after acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Isoda, Hiroyoshi; Itagaki, Yasushi; Nomura, Noriyuki [Fujieda Municipal Hospital, Shizuoka (Japan)] [and others

    1998-08-01

    To evaluate whether the findings of dual single-photon emission computed tomography (SPECT) with technetium-99m pyrophosphate (Tc-99m PPi) and thallium-201 were predictive of further cardiac events in their hospital course, we studied 130 patients recovering from acute myocardial infarction (AMI). Fifty-four patients showed overlapping of Tc-99m PPi and thallium-201 in the same location (overlap positive group), and 76 patients had no overlap (overlap negative group). Of the 130 patients, 36 (28%) had a cardiac event. In patients in the overlap positive group, the incidence of subsequent events was significantly higher than in patients in the overlap negative group (44% versus 16%; p<0.001). In the overlap positive group, the Tc-99m PPi uptake score and the number of overlap segments in patients with further events was significantly higher than those in patients without further events (10.2{+-}5.1 versus 6.4{+-}4.1, p<0.005 and 5.2{+-}2.0 versus 3.3{+-}1.3, p<0.001, respectively). These results suggest that patients who have a Tc-99m PPi and thallium-201 overlap negative scan can be candidates for early hospital discharge. In contrast, patients who have a greater number of overlap segments may require early catheterization and revascularization, so that simultaneous SPECT imaging Tc-99m PPi and thallium-201 might be useful for identifying patients with further ischemic risk after AMI in their hospital course. (author)

  15. Differentiation of malignant glioma and metastatic brain tumor by thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    The use of superdelayed thallium-201 single photon emission computed tomography (201Tl SPECT) for differentiating malignant gliomas from cerebral metastases was investigated in 23 patients (7 with meningioma, 6 with glioma, 7 with cerebral metastasis, 1 with each of neurinoma, abscess, and necrosis). 4 mCi of 201Tl was injected intravenously, and gamma camera scans were performed after 10 minutes and 4, 24, 72, and 96 hours (superdelayed scan). The mean thallium index of meningiomas was significantly higher than those of gliomas and cerebral metastases after 10 minutes, while the mean thallium indices of meningiomas and gliomas were significantly higher than those of cerebral metastases after 96 hours. The combination of early and superdelayed 201Tl SPECT may be useful in differentiating malignant gliomas from cerebral metastases. (author)

  16. Extraction chromatography in isotope production: application in the production of 67Ga and 201Tl

    International Nuclear Information System (INIS)

    Extraction chromatography was applied to the production of the radioisotopes 67Ga and 201Tl. 67Ga was produced by irradiation of natural zinc target with 24 MeV protons in a cyclotron. The separation of 67Ga was carried out by extraction chromatography from 6N HCL. 201Tl was produced in a similar way using lead as a precursor, and it was extracted using 4N HNO3 or HCL. (U.K.)

  17. Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem [Department of Nuclear Medicine, Institute of Nuclear Medicine and Allied Sciences, Brig. S. K. Mazumdar Road, 110054, Delhi (India)

    2004-04-01

    It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of {sup 201}Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of {sup 201}Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium bicarbonate augmentation may have significant implications for stress-thallium scintigraphy and may be a new parameter for defining myocardial viability. (orig.)

  18. Non-invasive evaluation of myocardial reperfusion by transthoracic Doppler echocardiography and single-photon emission computed tomography in patients with anterior acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Celutkiene Jelena

    2011-05-01

    Full Text Available Abstract Background The study was designed to evaluate whether the preserved coronary flow reserve (CFR 72 hours after reperfused acute myocardial infarction (AMI is associated with less microvascular dysfunction and is predictive of left ventricular (LV functional recovery and the final infarct size at follow-up. Methods In our study, CFR was assessed by transthoracic Doppler echocardiography (TDE in 44 patients after the successful percutaneous coronary intervention during the acute AMI phase. CFR was correlated with contractile reserve assessed by low-dose dobutamine echocardiography and with the total perfusion defect measured by single-photon emission computed tomography 72 hours after reperfusion and at 5 months follow-up. The ROC analysis was performed to determine test sensitivity and specificity based on CFR. Categorical data were compared by an ?2 analysis, continuous variables were analysed with the independent Student's t test. In order to analyse correlation between CFR and the parameters of LV function and perfusion, the Pearson correlation analysis was conducted. The linear regression analysis was used to assess the relationship between CFR and myocardial contractility as well as the final infarct size. Results We estimated the CFR cut-off value of 1.75 as providing the maximal accuracy to distinguish between patients with preserved and impaired CFR during the acute AMI phase (sensitivity 91.7%, specificity 75%. Wall motion score index was better in the subgroup with preserved CFR as compared to the subgroup with reduced CFR: 1.74 (0.29 vs. 1.89 (0.17 (p Conclusion The early measurement of CFR by TDE can be of high value for the assessment of successful reperfusion in AMI and can be used to predict LV functional recovery, myocardial viability and the final infarct size.

  19. Stress 201Tl-scintigraphy of the myocardium - comparison with veloergometry and selective coronary arteriography in patients with chronic ischeemic heart disease

    International Nuclear Information System (INIS)

    The study has been carried out on 53 patients with complaints of pain with anterior thoracal localization, clinically diagnosed as stable angina pectoris at mild physical efforts; 31 of the patients had a case history of passed myocardial infarction. All patients have been subjected to right-and left-side cardiac catheterization, left ventricular ventriculography and standard selective coronary arteriography 3 to 20 days before or after stress scintigraphy (SS) with 201Tl-chloride. SS is carried out on a static veloergometer by stepwise loading; every 6 min a registration of the 6 thorax ECG-deviations is made and the arterial pressure is mesured. 201Tl-chloride (74 MBk) is injected at the pick of the physical burden. The myocardial perfusion is visualized on 'Nuclear Ohio' gamma camera with a parallel collimator in 3 projections in the course of 6 min for each projection, which allows to evaluate the perfusion of 9 segments of the myocardium. Two hours after the physical loading the myocardial perfusion at rest is studied by the same method. The comparative study shows a considerable advantage of the Tl-SS compared to veloergometry of patients with insignificant haemodynamic coronary stenosis: it allows a precise evaluation of the myocardial perfusion in cases when the appraisal of ECG-changes after a physical loading is difficult. 3 tabs., 5 refs

  20. Evaluation of thallium-201 washout in patients with ischemic heart disease using ring-type single photon emission CT

    International Nuclear Information System (INIS)

    With the emergence of single photon emission computed tomography (SPECT), thallium-201 (Tl) myocardial scanning has become the important diagnostic procedure of choice for ischemic heart disease; however, clinical and diagnostic aspects still remain unclear. The present study explored kinetics of Tl within the myocardium using ring-type SPECT that allows rapid sequential scanning. Three groups containing five patients with effort angina pectoris (EAP), old myocardial infarction (OMI), or chest pain syndrome (CPS), were scanned during exercise five times at five min intervals after injection of 2.5 - 4.0 mCi of Tl, and subsequently scanned at one, two, and three hr later. Time-activity curves and washout rates in five regions of interest were examined. At 30 min, washout rate was 10 % in the EAP and OMI groups and 0.2 % in the CPS group, showing significant difference between the former two groups and the latter group. This implies that ring-type SPECT may play an important role in elucidating the mechanism of Tl washout and myocardial blood flow, although it has still disadvantages of limited transaxial three scans and inability to correct scattered rays. (Namekawa, K.)

  1. Preoperative diagnosis of nodular thyroid tumor by delayed scintigraphy using 201TlCl

    International Nuclear Information System (INIS)

    Thallous chloride-201Tl [201TlCl] tends to readily concentrate in thyroid nodules. Since 1984, we have performed xerography, ultrasonography and scintigraphy for nodular thyroid tumors to establish the preoperative diagnosis. Scintigraphy was carried out in patients who exhibited cold nodules by 99mTc or 131I and high uptake in an early scan by 202Tl. Both procedures were performed in 54 patients within 10 minutes and 2 hours later after intravenous administration of 201TlCl. The scintigrams of 17 cases of the thyroid carcinomas [papillary adenocarcinoma in 14 cases, follicular adenocarcinoma in 2 cases, anaplastic carcinoma in 1 case] exhibited abnormally high activities in the early image corresponding to the cold nodules by 99mTc or 131I, and the activities remained clearly detectable in the delayed scintigram. In 6 benign cases [4 of follicular adenoma, and one each of adenomatous goiter and adenomatous goiter + follicular adenoma] abnormal activity still remained in the delayed image. These cases require careful follow-up, because they have high probability of developing carcinoma. It was found that the abnormal activity in the delayed scintigram almost always reflected malignant thyroid tumors while the activity that vanished in the delayed scintigram did not always reflect benign lesion. Thus the combination of early and delayed scintigraphy using 201TlCl appears tigraphy using 201TlCl appears to be useful in differentiating malignant thyroid tumors from benign ones. (author)

  2. Quantification of myocardial infarction: a comparison of single photon-emission computed tomography with pyrophosphate to serial plasma MB-creatine kinase measurements

    International Nuclear Information System (INIS)

    Single photon-emission computed tomography (SPECT) with /sup 99m/Tc-pyrophosphate (PPi) has been shown to estimate size of myocardial infarction accurately in animals. The authors tested the hypothesis that SPECT with /sup /sup 99m//Tc-PPi and blood pool subtraction can provide prompt and accurate estimates of size of myocardial infarction in patients. SPECT estimates are potentially available early after the onset of infarction and should correlate with estimates of infarct size calculated from serial measurements of plasma MB-creatine kinase (CK) activity. Thirty-three patients with acute myocardial infarction and 16 control patients without acute myocardial infarction were studied. Eleven of the patients had transmural anterior myocardial infarction, 16 had transmural inferior myocardial infarction, and six had nontransmural myocardial infarction. SPECT was performed with a commercially available rotating gamma camera. Identical projection images of the distribution of 99mTc-PPi and the ungated cardiac blood pool were acquired sequentially over 180 degrees. Reconstructed sections were color coded and superimposed for purposes of localization of infarct. Areas of increased PPi uptake within myocardial infarcts were thresholded at 65% of peak activity. The blood pool was thresholded at 50% and subtracted to determine the endocardial border for the left ventricle. Myocardial infarcts ranged in size from 1 to 126 gram equivalents (geq) MB-CK. The correlation of MB-CK ets (geq) MB-CK. The correlation of MB-CK estimates of size of infarct with size determined by SPECT (both in geq) was good (r = .89 with a regression line of y = 13.1 + 1.5x)

  3. Clinical studies on thallium-201 myocardial perfusion imaging in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    201Tl myocardial perfusion imaging in patients with ischemic heart disease was discussed. Infarcted areas, which had been diagnosed with electrocardiograms and coronary arteriograms of 27 patients with cardial infarction, were visualized as a decrease or a defect of myocardial uptake of 201Tl on their rest myocardial perfusion images (MPI). The pictures of them obtained from rest MPI were well correlated with their coronary arteriograms. Myocardial uptake of 201Tl was increased by exercise in normal subjects, but decreased uptake of RI was observed on stress MPI of 12 patients with effort angina and 5 of 6 patients with cardial infarction. These findings were also observed in their postexertion electrocardiogram. To visualize images more clearly, an phantom experiment was performed and clear images close to the actual size were obtained. Ratio of myocardial uptake of 201Tl in ischemic areas after exercise was decreased significantly in patients with angina and cardiac infarction, though myocardial uptake of 201Tl in healthy subjects was not changed by exercise. A defect of myocardial uptake of 201Tl was induced by methacholine in 4 patients with a variant form of angina and was induced by exercise in 2. Improvement of myocardial uptake of 201Tl was observed on images of patients in whom blood flow in local myocardium had been improved after the operation to make bypass. (Tsunoda, M.)ion to make bypass. (Tsunoda, M.)

  4. Diagnosis of intracranial malignant lymphoma by 67Ga and 201Tl SPECT

    International Nuclear Information System (INIS)

    Six patients with malignant lymphoma of the brain underwent 67Ga and 201Tl brain SPECT. For the quantitative analysis, count ratios of a lesion to the normal brain (L/N) were calculated. In 201Tl SPECT studies, an L/N ratios ranged from 2.3 to 3.2, with a mean of 2.9±0.4. In 67Ga SPECT studies, an L/N ratios ranged from 4.4 to 6.6 with a mean of 5.7±0.8. 67Ga SPECT showed much more intense tracer uptake than 201Tl SPECT and the degree of 67Ga accumulation seems to be in proportion to the viability of malignant lymphoma. We came to the conclusion that quantitative 67Ga SPECT appears to be useful in detecting and managing malignant lymphoma in the brain. (author)

  5. Proton induced reactions on natural Pb targets. A potential new cyclotron method for 201Tl production

    International Nuclear Information System (INIS)

    The basis for a new cyclotron method for production of no-carrier-added 201Tl, from its grandparent 201Bi via the Pb(p,xn)201Bi ? 201Pb ? 201Tl reaction is presented here. Thick-target yields (?Ci/?Ah) for the 201Pb and 200Pb induced radioactivities were measured over the 65- to 43-MeV proton-energy range. The experimental data indicate that the 201Tl yields could be optimized by using Pb targets enriched in 206Pb, 207Pb, and, or 208Pb, which are expected to provide greater overall yields than current methods, as well as material of high-chemical, radiochemical and radionuclidic quality for radiopharmaceutical production. (author)

  6. Effect of collateral circulation on myocardial protection in patients with acute myocardial infarction. Comparison of technetium-99m-tetrofosmin myocardial single photon emission computed tomography and coronary angiography

    International Nuclear Information System (INIS)

    Evaluation of myocardial blood flow from collateral vessels into the infarct area has been estimated by coronary angiography. In patients with acute myocardial infarction with Thrombolysis in Myocardial Infarction (TIMI) 0 flow, myocardial tracer uptake on single photon emission computed tomography (SPECT) images can predict the collateral blood flow in the infarct area if technetium (Tc)-99m-tetrofosmin was administered before recanalization. The present study investigated whether collateral blood flow evaluated by myocardial scintigraphy is a good predictor of myocardial salvage in patients with acute myocardial infarction. The study group consisted of 30 patients (mean age 65±14 years, 23 males, 7 females) with first acute myocardial infarction and coronary angiography evidence of total occlusion (TIMI 0) within 12 hr after the onset. All patients had one vessel disease related to infarction and TIMI 3 flow after percutaneous coronary intervention (PCI). Tc-99m-tetrofosmin was injected intravenously before the PCI. The regional severity score index (RSSI) was obtained from SPECT using the 17 segment method with the four-point scoring system. Myocardial viability was evaluated by the RSSI obtained from thallium-glucose-insulin infusion SPECT after 1 week and regional wall motion score index obtained from echocardiography during the chronic phase. The patients were divided into two groups according to the angiographic collateral finding. There were no differences inral finding. There were no differences in RSSI on thallium-glucose-insulin SPECT and regional wall motion score between the good collateral group (n=8) and poor collateral group (n=22). Myocardial Tc-99m-tetrofosmin RSSI was similar in these groups. On the other hand, the patients were divided according to Tc-99m-tetrofosmin scintigraphic evaluation before PCI. RSSI on thallium-glucose-insulin SPECT was significantly greater (0.7±0.5 vs 1.5±0.4, p<0.01) and regional wall motion score was significantly less (1.46±0.50 vs 2.08±0.78, p<0.05) in the lower Tc-99m-tetrofosmin RSSI (<1.9) group (n=22) compared with the higher RSSI (?1.9) group (n=8). In addition, a significant correlation was obtained between Tc-99m-tetrofosmin RSSI and regional wall motion score index (r=0.53, p<0.01). The collateral flow evaluated by scintigraphy was significantly con-elated with myocardial viability. (author)

  7. Effect of diltiazem on myocardial infarct size estimated by enzyme release, serial thallium-201 single-photon emission computed tomography and radionuclide angiography

    International Nuclear Information System (INIS)

    Diltiazem is a calcium antagonist with demonstrated experimental cardioprotective effects. Its effects on myocardial infarct size were studied in 34 patients admitted within 6 hours after the first symptoms of acute myocardial infarction. These patients were randomized, double-blind to placebo or diltiazem (10-mg intravenous bolus followed by 15 mg/hr intravenous infusion during 72 hours, followed by 4 X 60 mg during 21 days). Myocardial infarct size was assessed by plasma creatine kinase and creatine kinase-MB indexes, perfusion defect scores using single-photon emission computed tomography with thallium-201 and left ventricular ejection fraction measured by radionuclide angiography. Tomographic and angiographic scanning was performed serially before randomization, after 48 hours and 21 days later. Groups were comparable in terms of age, sex, inclusion time and baseline infarct location and size. Results showed no difference in creatine kinase and creatine kinase-MB data between controls and treated patients, a significant decrease in the perfusion defect scores in the diltiazem group (+0.1 +/- 3.0 placebo vs -2.2 +/- 1.9 diltiazem, p less than 0.02) and a better ejection fraction recovery in the diltiazem group (-4.2 +/- 7.4 placebo vs +7.7 +/- 11.2 diltiazem, p less than 0.05). Myocardial infarct size estimates from perfusion defect scores and enzyme data were closely correlated. These preliminary results suggest that diltiazem may reduce ischemic injury in acute mazem may reduce ischemic injury in acute myocardial infarction

  8. Dual myocardial single photon emission computed tomography (SPECT) using thallium-201 and I-123-?-methyl-i-pentadecanoic acid in patients with Duchenne's progressive muscular dystrophy

    International Nuclear Information System (INIS)

    Dual single photon emission computed tomography (SPECT) was performed in 31 patients with Duchenne's progressive muscular dystrophy (DMD) using 123I-?-methyl pentadecanoic acid (BMIPP) for myocardial fatty acid metabolism and 201thallium (Tl)-chloride for myocardial perfusion. The left ventricle was divided into 9 segments, and accumulation of the radiotracers was assessed visually for each segment to calculate defect score for each tracer. There was some degree of decrease in myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP: 67%, Tl: 63%), followed by the posterior wall, lateral wall, and anterior wall. On the other hand, reduced accumulation was less common at the septum. BMIPP showed a higher accumulation than Tl in all segments but the septum. When BMIPP defect score was larger than Tl defect score, BMIPP defect score tended to increase during 4 years follow-up (p Tl defect score revealed a slightscore > Tl defect score revealed a slight fibrosis or normal myocardium. It can be concluded that the dual SPECT myocardial scintigraphy using BMIPP and Tl provides accurate information about disease progression of the heart in patients with DMD by detecting abnormalities of the myocardial metabolism of each substance, thereby enabling the assessment of left ventricular function. (author)

  9. Evaluating the sensitivity and specificity of 201Tl SPECT in intracranial tumoral pathology

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the sensitivity of SPECT with 201Tl in detecting the cerebral tumors. A hundred and forty nine explorations were carried out (107 SPECT in patients clinically suspected and/or cerebral tumor radiography, 42 SPECT in patients treated for cerebral tumor to evaluate the persistence of the tumoral tissue immediately post-operation, or the presence of a tumoral recurrence). The SPECTs were achieved 15 minutes after the IV injection of 185 MBq of 201Tl with a double head Elscint Helix HR camera with fan collimators. The reconstructions were obtained by retro-projection with a Metz 3.13 filter. As the brain normally do not capture 201Tl, any fixation of 201Tl was considered an positive examination. The final diagnosis was based either on the histology (n = 41) or on clinical evolution (n = 149). The pathologies recorded were: 33 glial tumors, 32 metastases (51 lesions), 14 meningiomas, 1 hypophyseal adenoma, 1 cranio-pharyngogioma, 1 malign lymphoma, 1 gr.4 neurinomas, 1 arachnoid cyst, 34 AVCs, 24 normal, 2 complete surgical extirpations, and 5 necroses after treatment. In our population the sensitivity of SPECT with 201Tl for the diagnosis of intracranial tumors was calculated to be 91.5% and the specificity, 98.5%. We have met a false positive (recent hemorrhagic AVC) and 7 false negatives (4 metastases of which 3 were under 1 cm and another largely necrotic, 3 patients presentinger largely necrotic, 3 patients presenting residual tumoral tissue immediately post-operation, presently in recurrence). These excellent results prove the utility of SPECT with 201Tl both for positive diagnosis of cerebral tumors and for evaluation of these tumors after treatment

  10. Experimental investigation of 201TlCl-scintigraphy in evaluating therapeutic effect of hyperthermia

    International Nuclear Information System (INIS)

    We investigated the usefulness of 201Tl-scintigraphy in the evaluation of therapeutic effect of hyperthermia. Satoh's experimental lung cancer tumors implanted in the right thighs of donryu rats were treated with hyperthermia using water bath. Tumors were heated at 44degC or 46degC for 15 min. 201Tl-scintigraphy was obtained before, immediately after and 24 hrs after treatment. Counts ratio of the tumor of the normal muscle (T/N ratio) was measured by gamma camera. We examined blood flow of the tumor, and relative tumor growth rate, and performed autoradiogram and histopathological examination of the tumor after 201Tl-scintigraphy. Immediately after hyperthermia, T/N ratio and blood flow of the tumor significantly decreased (p201TlCl in the tumor decreased diffusely. Histopathological finding showed congestion, thrombosis, and swelling of endothelial cells. These results suggest that the decrease in T/N ratio may be caused by the vascular damage due to hyperthermia. The T/N ratio recovered 24 hrs after hyperthermia but was still lower than that for the control. Autoradiogram showed that 201TlCl greatly accumulated in viable tumor tissue but was hardly seen in the necrotic tumor tissue. These results suggest that the decrease in T/N ratio may be caused by increase of necrotic areas. The T/N ratio 24 hrs after hyperthermia correlated (r=0.83) with relative tumor growth rated (r=0.83) with relative tumor growth rate on 7th day after hyperthermia and, therefore, can be used as an indicator of relative tumor growth rate. 201Tl-scintigraphy can be useful for prediction of therapeutic effect of hyperthermia. (author)

  11. The comparative study of PET, SPECT imaging and pathology on experimental animal model of myocardial ischemia

    International Nuclear Information System (INIS)

    Objective: To compare 201Tl SPECT and 18F-fluorodeoxyglucose (FDG) PET imaging for the assessment of myocardial viability of chronic myocardial ischemia in pigs. Methods: 201Tl SPECT imaging and 18F-FDG PET imaging were performed on 10 pig models of chronic myocardial ischemia induced by ameroid constrictors. The viable myocardial segments were also determined by pathologic hemotoxylin and eosin (HE) staining to identify myocardial changes. Results: In 81 myocardial segments, viable myocardial segments assessed by 18F-FDG PET and 201Tl SPECT imaging were 73(90.1%) and 62(76.5%) respectively, and were statistically different (?2=0.073, P>0.05). Conclusion: The accuracy of 18F-FDG PET imaging was much more higher than 201Tl SPECT imaging for the assessment of viable myocardium. (authors)

  12. 201Tl /99mTc Subtraction Scan in the Diagnosis of Hyperparathyroidism

    International Nuclear Information System (INIS)

    201Tl /99mTc pertechnetate subtraction scintigraphy of the parathyroid gland performed in a study of 8 patients with clinical and biochemical evidence of hyperparathyroidism for diagnosis and localization of the lesion prior to surgery. 6 cases of parathyroid adenomas were accurately localized and 2 cases of diffuse hyperplasia associated with chronic renal failure(CRF) and multiple endocrine neoplasia(MEN) type I. 201Tl /99mTc pertechnetate scan was useful for patients with hyperparathyroidism, especially in definite localization preoperatively.

  13. {sup 201}Tl /{sup 99m}Tc Subtraction Scan in the Diagnosis of Hyperparathyroidism

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    Ahn, Bo Young; Sohn, Hyung Sun; Kim, Euy Neyung; Kim, Sung Hoon; Chung, Soo Kyo; Kim, Choon Yul; Baek, Yong Whee; Shinn, Kyung Sub [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1995-09-15

    {sup 201}Tl /{sup 99m}Tc pertechnetate subtraction scintigraphy of the parathyroid gland performed in a study of 8 patients with clinical and biochemical evidence of hyperparathyroidism for diagnosis and localization of the lesion prior to surgery. 6 cases of parathyroid adenomas were accurately localized and 2 cases of diffuse hyperplasia associated with chronic renal failure(CRF) and multiple endocrine neoplasia(MEN) type I. {sup 201}Tl /{sup 99m}Tc pertechnetate scan was useful for patients with hyperparathyroidism, especially in definite localization preoperatively.

  14. High-contrast film copying for 201Tl cardiac image processing

    International Nuclear Information System (INIS)

    To evaluate the usefulness of high-contrast film copying as an economical means of enhancing contrast in 201Tl cardiac images, stress and rest studies of 47 patients with and 19 patients without coronary artery disease were evaluated. A total of 66 sets of four different image formats were independently interpreted by five observers. The analysis of the receiver operating characteristic curves suggested that the high-contrast film copies were superior to their original analog images and comparable with computer-processed images in diagnostic yield. It appears that contrast enhancement by simple film copying can improve the accuracy of 201Tl image interpretation

  15. 201Tl-SPECT, 1H-MRS, and MIB-1 labeling index of central neurocytomas: three case reports

    International Nuclear Information System (INIS)

    Background: The proliferative activity and metabolic features of three central neurocytomas were investigated using the findings of thallium-201 single photon emission computed tomography (201Tl-SPECT) and proton magnetic resonance spectroscopy (1H-MRS), and the MIB-1 labeling index (MIB-1 LI). Method: The early and delayed 201TI indices were calculated as the ratio of tumor to normal brain tissue uptake by 201TI-SPECT. In vivo single-voxel 1H-MRS was performed with echo time of 272 msec to evaluate the metabolites including choline (Cho), N-acetyl aspartate (NAA) and creatine/phosphocreatine (Cre). An external standard reference was used to semiquantitate each metabolite. MIB-1 LI was determined in the surgical specimens. Findings: The MIB-l LI was 0.5 %, 1.2 %, and 7.5 % in an atypical central neurocytoma without intraventricular extension. Significant 201TI uptake was observed on delayed images in all three central neurocytomas. 1H-MRS showed the high Cho peaks relative to the NAA and Cre peak. The signal at 3.55 ppm, which may be due to inositol or glycine, was observed in one central neurocytoma. Interpretation: Both 201TI-SPECT and 1H-MRS did not reflect the proliferative potential of central neurocytomas. (author)

  16. Effects of exercise training on myocardial fatty acid metabolism in rats with depressed cardiac function induced by transient ischemia

    International Nuclear Information System (INIS)

    The effects of exercise training on metabolic and functional recovery after myocardial transient ischemia were investigated in a rat model. Male Wistar Kyoto rats were subjected either to a 30-min left coronary artery occlusion followed by reperfusion or to a sham operation. At 4 weeks after operation, the rats were randomly assigned either to sedentary conditions or to exercise training for 6 weeks. In the ischemic rats, pinhole SPECT (single photon emission computed tomography) imaging with thallium-201 (201Tl) and 123I-(?-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) showed a reduction of both myocardial perfusion and fatty acid metabolism in the risk zone of the left ventricle (LV). The LV was dilated and the ejection fraction was decreased after ischemic injury. The severity score showed a significant decrease on both 201Tl and BMIPP (201Tl, from 19.9±2.7 to 17.0±2.2, p<0.05; BMIPP, from 21.5±2.4 to 18.6±1.9, p<0.05) after exercise training in the ischemic trained rats, but did not change significantly in their sedentary counterparts. Plasma levels of free fatty acids normalized in the ischemic trained rats, but elevated in the ischemic sedentary rats (0.53±0.05 vs 0.73±0.06 mmol/L, p<0.05). Furthermore, the trained rats had a significant increase in LV stroke volume (0.25±0.02 vs 0.21±0.01 ml/beat, p<0.05) and adaptive cardiac hypertrophy. These findings demonstrate that adaptive improvements in myocardiadaptive improvements in myocardial perfusion, fatty-acid metabolism and LV function were induced by exercise training after transient ischemia. (author)

  17. Comparison of Myocardial perfusion by ECG-gated myocardial perfusion single photon emission computed tomography method with coronary angiography in all of the coronary vessels and individual coronary vessels in patients with suspected or known coronary artery disease

    International Nuclear Information System (INIS)

    In order to compare myocardial perfusion using 99mTc Tetrofosmin ECG gated myocardial perfusion single photon emission computed tomography (ECG gated MP-SPECT) with coronary angiography, this descriptive study was performed in 47 patients. Sensitivity and specificity of myocardial perfusion scan with coronary angiography were calculated in all of the coronary vessels and individual coronary vessel. The sensitivity of perfusion scan of myocardium in case of LAD was 94.28% and the specificity was 91.66%. For LCX these figures were 82.35% and 90% and for RCA, 95.83% and 78.26% Respectively The overall sensitivity and specificity of myocardial perfusion scan in all of the coronary vessels was 91.66% and 81.81 % respectively. Our findings are consistent with other published studies. (author)

  18. A partial defect in technetium-99m pyrophosphate image suggesting cardiac rupture following acute myocardial infarction

    International Nuclear Information System (INIS)

    We present the case of a 70-year-old woman with acute myocardial infarction who died of cardiac rupture on the 2nd hospital day. Dual isotope single photon emission tomography (SPET) using thallium-201 chloride and technetium-99m pyrophosphate (PYP) perforemd on the 2nd hospital day showed a large perfusion defect in the anteroseptal wall on 201Tl image and a increased accumulation on 99mTc-PYP image in the anterior area consistent with a partial defect. Autopsy performed 1 h after death revealed a tear in the left ventricular anterior wall consistent with the defect on the 99mTc-PYP image. We propose that the finding of a partial defect in 99mTc-PYP is an interesting finding which may be associated with cardiac rupture following acute myocardial infarction. (orig.)

  19. Reversible myocardial ischaemia or irreversible myocardial fibrosis

    International Nuclear Information System (INIS)

    The results of biphasis 201thallium (201Tl) scanning were compared with those of coronary arteriography, left ventricular angiography and stress ECG in 56 patients with coronary artery disease and six with no evidence of heart disease. There were 104 201Tl defects, 50 of them reversible. The defects were always located in the area supplied by a critically stenotic coronary artery. Correlation of regional wall motion with 201Tl activity demonstrated that in all forms of abnormal wall motion there was either ischaemia or fibrosis. The resting LV angiogram thus does not make it possible to distinguish between myocardial ischaemia and fibrosis. Taking the LV angiogram as a standard, the rate of false-positive 201Tl scintigrams was 5%, that of false-negative ones 23%. The biphasic 201Tl scintigram was more sensitive than the stress ECG in detecting myocardial ischaemia. It furthermore made it possible to localize the ischaemic (or fibrotic) region within the LV and to estimate its size. (orig.)

  20. Thallium-201 single photon emission tomography of myocardium. Additional information in reinjection studies is dependent on collateral circulation

    International Nuclear Information System (INIS)

    A second thallium-201 injection under resting conditions is able to improve the differentiation between myocardial scar and ischaemia when compared with simple redistribution imaging. The aim of this study was to evaluate the dependence of this improvement on the degree of stenosis and the presence of collaterals. Single photon emission tomography (SPET) studies under exercise, redistribution and reinjection conditions were performed on 84 patients with 181 stenotic vessels (70 left anterior descending, 47 left circumflex, 64 right coronary artery) and compared with angiography. An improvement of the 201Tl uptake in the reinjection image was observed in 53% of the myocardial areas served by a coronary artery with a stenosis of over 90%. This is compared with 13% of the areas served by a vessel with a stenosis between 50% and 90%. Some 90% of the collateralized areas showed a fill-in effect, but only 7 of the 118 without angiographically visible collateralization (6%). The dependence of the fill-in effect, collateralization and >90% stenosis was highly significant (?2 test, P90% narrowing. The fill-in effect was closely correlated to the presence of collaterals. In these cases, the fill-in may be an indication for hibernating myocardium. (orig.)

  1. /sup 99m/Tc-pyrophosphate imaging in patients with acute myocardial infarction: Comparison of planar imaging with single-photon tomography with and without blood pool overlay

    International Nuclear Information System (INIS)

    To test the hypothesis that single-photon emission computed tomography (SPECT) of /sup 99m/Tc-pyrophosphate (/sup 99m/Tc-PPi) with and without the overlay of tomographic blood pool scintigrams might detect small infarcts not identified by planar imaging, 52 patients were studied 3.2 +/- 2.0(SD) days after hospital admission for suspected acute myocardial infarction. Patients were chosen prospectively for tomographic study primarily, but not exclusively, because planar four-view imaging with /sup 99m/Tc-PPi was either negative or equivocal. SPECT was performed with a commercial rotating detector system immediately after planar imaging on one occasion. Corresponding /sup 99m/Tc-PPi and blood pool sections were mapped into opposite halves of a bichromic color table and displayed as an overlay. Planar images, SPECT and SPECT with blood pool overlay were interpreted separately and in random order without knowledge of clinical data. Seventeen patients had transmural infarcts (four anterior, 13 inferior), 19 had nontransmural infarcts, and 16 patients did not have acute myocardial infarction. The sensitivity of SPECT with blood pool overlay was significantly better than planar imaging for the entire group with myocardial infarction (97% vs 78%; p less than .025); this was primarily due to increased sensitivity in the detection of nontransmural myocardial infarction (95% vs 67%; p less than .05), although in one additional patient inferior transmural myocardial infarction waserior transmural myocardial infarction was also detected by the SPECT overlay technique. The specificities of the SPECT overlay technique and planar imaging were not significantly different; however, receiver operating characteristic analysis showed enhanced observer confidence with the tomographic method. SPECT without overlay was intermediate in sensitivity and specificity

  2. Preoperative diagnosis of nodular thyroid tumor by delayed scintigraphy using /sup 201/TlCl

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    Kumai, Megumi; Hatayama, Naoki; Takahashi, Mitsuaki; Shirato, Masaru; Unno, Tokuji

    1987-08-01

    Thallous chloride-/sup 201/Tl (/sup 201/TlCl) tends to readily concentrate in thyroid nodules. Since 1984, we have performed xerography, ultrasonography and scintigraphy for nodular thyroid tumors to establish the preoperative diagnosis. Scintigraphy was carried out in patients who exhibited cold nodules by /sup 99m/Tc or /sup 131/I and high uptake in an early scan by /sup 202/Tl. Both procedures were performed in 54 patients within 10 minutes and 2 hours later after intravenous administration of /sup 201/TlCl. The scintigrams of 17 cases of the thyroid carcinomas (papillary adenocarcinoma in 14 cases, follicular adenocarcinoma in 2 cases, anaplastic carcinoma in 1 case) exhibited abnormally high activities in the early image corresponding to the cold nodules by /sup 99m/Tc or /sup 131/I, and the activities remained clearly detectable in the delayed scintigram. In 6 benign cases (4 of follicular adenoma, and one each of adenomatous goiter and adenomatous goiter + follicular adenoma) abnormal activity still remained in the delayed image. These cases require careful follow-up, because they have high probability of developing carcinoma. It was found that the abnormal activity in the delayed scintigram almost always reflected malignant thyroid tumors while the activity that vanished in the delayed scintigram did not always reflect benign lesion. Thus the combination of early and delayed scintigraphy using /sup 201/TlCl appears to be useful in differentiating malignant thyroid tumors from benign ones.

  3. The comparison of simultaneous dual-isotopic myocardial perfusion SPECT imaging in the detection of myocardial viability

    International Nuclear Information System (INIS)

    Objective: The comparison of the clinical role of stress-redistribution/reinjection with dual isotopes of 99Tcm-methoxyisobutylisonitrile (MIBI) and 201TI in the detection of myocardial viability. Methods: One hundred and sixty patients with clinically suspicious coronary artery disease (CAD) were included. All had intravenous injection with 740 MBq of 99Tcm-MIBI. Pharmacological challenge with dobutamine (5 ?g ·-1 · min-1) was given to all at 15 min after injection of 99Tcm-MIBI. At the end of pharmacological challenge with dobutamine, 111 MBq of 201Tl was injected to all. Myocardial SPECT images were performed in all at 10-min (stress) and 3-h (redistribution/rest) after injection. The 201Tl (37 MBq) would be given to those patients with myocardial perfusion defect at stress images by 201Tl and were demonstrated by both 201Tl (redistribution) and 99Tcm-MIBI (rest). Coronary angiography (CAG) was performed within two weeks. ?2-test was used with SAS 6.12. Results: Coronary artery abnormalities were found in all with 76 patients had one vessel disease, 51 had two and 33 had three. Of the 152 patients who had myocardial perfusion defect during stress images, 63 had redistribution by both 201TI and 99Tcm-MIBI. 5 had re-distribution by 201Tl only. 9 hribution by 201Tl only. 9 had redistribution by 99Tcm-MIBI only, and 75 had no redistribution in 201Tl or 99Tcm-MIBI images. The sensitivity of detection myocardial viability with myocardial SPECT images between 201Tl at redistribution (66.0%, 68/103) and 99Tcm-MIBI at rest (69.9%, 72/103) were insignificant (?2=0.36. P>0.05). Of the 75 patients who did not have redistribution in 201Tl or 99Tcm-MIBI images. 34.7% (26/75) had myocardial perfusion when reinjection of 201Tl. In all, there were eight false negative myocardial perfusion SEPCT images. Three were triple vessel disease, one Was two, three were one, and the other was patent collateral circulation. Conclusions: Stress. redistributed/reinjection 201TI myocardial perfusion SPECT imaging is superior to stress 201Tl/rest 99Tcm-MIBI simultaneous dual-isotopic myocardial imaging in the detection of myocardial viability. (authors)

  4. Studies on portal systemic circulation by oral administration of 201Tl enclosed enteric coated capsule

    International Nuclear Information System (INIS)

    Thallium-201 enclosed enteric coated capsule was prepared and administered orally to evaluate portal systemic circulation in 11 control subjects and 31 patients with various liver diseases by investigating scintigraphic appearance and the heart-to-liver uptake ratio (H/L ratio). In 10 patients with liver cirrhosis and one with chronic hepatitis, the results of H/L ratio were compared to those obtained by 201Tl per-rectal administration. 1. It was fundamentally confirmed that 201Tl enclosed enteric coated capsule was not broken down in the artificial gastric juice, but nearly completely melted 15 minutes after soaking in the artificial intestinal juice. 2. Clinical study was successfully completed in 36 out of 42 cases (86 %). Unsuccessful cases were found in 2 with capsule collapse in the stomach and 4 with its poor moving to the duodenum. 3. In control subjects the liver was clearly visualized and the mean value of H/L ratio was 0.32 which is lower than that of 201Tl per-rectal administration previously reported. H/L ratio in patients with chronic and acute hepatitis was nearly equal to that in control subjects. H/L ratio in patients with liver cirrhosis was slightly higher than that in control subjects, but there was no significant difference between them. In cases with esophageal varices, H/L ratio was not so high compared to that in control subjects. Out of 7 patients showing high H/L ratio more than 0.8 in 201Tl per-rectal administration, only one showed similar high ratio (1.07) in oral administration of 201Tl enclosed enteric coated capsule. In this case the shunting from superior mesenteric vein to inferior vena cava connection was confirmed. From these results, it was considered that the shunting volume of superior mesenteric vein through esophageal varices is small. 4. A possibility of a new administration of radioisotope with enteric coated capsule was emphasized. (author)

  5. Diagnostic value of 201Tl-chloride scintigraphy for thyroid tumors

    International Nuclear Information System (INIS)

    Among the 98 cases of thyroid disease on whom we performed 201Tl-chloride scintigraphy, we examined 82 cases which were given histological diagnosis. Of 19 cases of thyroid carcinoma, 15 cases were positive (78.9%). 3 cases among the 15 showed a strong accumulation in the metastatic lymph nodes of the neck and mediastinum. Of 40 cases of thyroid adenoma, 10 cases were positive (25%). In comparison, cases of hyperthyroidism and chronic thyroiditis were all positive and cases of subacute thyroiditis were all negative. The histological types of thyroid tumors were examined. Of 14 cases of papillary carcinoma, 12 cases were positive (85.7%). 2 cases of negative scanning showed almost complete cystic degeneration. 3 cases of follicular carcinoma were all positive, but 2 cases of anaplastic carcinoma were negative. With respect to adenomas, 7 cases of tubular adenoma and 3 cases of trabecular adenoma were all positive, but cases of colloid adenoma and thyroid cyst were all negative. As to the uptake ratio of 201Tl-chloride into the thyroid carcinoma and adenoma tissue, it was observed that papillary carcinoma absorbed 2.65 times as much as normal thyroid tissue, follicular carcinoma absorbed 5.82 times as much, tubular adenoma absorbed 5.45 times as much, trabecular adenoma absorbed 5.67 times as much, but colloid adenoma absorbed 1.65 times as much as normal thyroid tissue. From the above mentioned results, it was concluded that 201Tl-chlor was concluded that 201Tl-chloride has no specific affinity for malignant tumors and cannot be used to discriminate between carcinoma and adenoma, but the nodule which showed positive scanning by 201Tl-chloride must be indicated for surgery. (author)

  6. Myocardial scintigraphy and radionuclide ventriculography in myocardial infarction

    International Nuclear Information System (INIS)

    149 patients with acute (n = 75) myocardial infarction and 74 postinfarctions, angiographically confirmed, were investigated by 201Tl myocardial scintigraphy and subsequent radionuclide ventriculography. Quantitative evaluation of the scintigram showed 201Tl storage defects in 92% in the acute stage and in 79% in the later stage. The sensitivity of identification of the posterior wall infarction was consistently markedly less than for anterior wall infarctions and could not be increased by additional application of 99sup(m)Tc methylene disphosphonate. By the combined application of myocardial scintigraphy and radionuclide ventriculography the functional effects of the infarction can be described non-invasively. (orig.)

  7. Study of the predictors and lesion characteristics of ischemic heart disease patients with false negative results in stress myocardial perfusion single-photon emission tomography

    International Nuclear Information System (INIS)

    The predictors and lesion morphology of patients with ischemic heart disease testing false negative results in stress myocardial perfusion single-photon emission computed tomography (SPECT) was investigated. Subjects were 58 consecutive patients who underwent coronary angiography (CAG), even though they showed normal findings in stress myocardial perfusion SPECT. Age, gender, methods of stress, perfusion agent, coronary risk factors, angina symptoms, and electrocardiographic changes were investigated as predictors by multivariate analysis. For lesion morphology, significant stenotic lesions were studied for morphological characteristics and reference diameter (RD), percentage diameter stenosis (%DS), minimum lumen diameter (MLD), and lesion length (LL) were measured. CAG revealed 30 significant stenotic lesions in 18 patients. Logistic regression analysis revealed significant predictors to be age (odds ratio (OR) 1.118, p<0.05), typical anginal pain (OR 21.09, p<0.01), and hypertension (OR 8.336, p<0.05). For lesion morphology, there were only 2 diffuse lesions and the mean RD, %DS, MLD, and LL were 3.03±0.9 mm, 63.1±9.3%, 1.13±0.49 mm, and 13.2±7.0 mm, respectively. Sufficient caution is believed necessary in the interpretation of normal findings of stress myocardial perfusion SPECT when the patient is elderly, complains of typical anginal pain, or has hypertension. In regard to characteristics of lesion morphology, there were hardly any diffuse lesions. (author)e hardly any diffuse lesions. (author)

  8. Study of myocardial viability using thallium-201 in patients with a history of infarctions: Is reinjection necessary?

    International Nuclear Information System (INIS)

    An analysis was performed of 84 patients with a history of myocardial infarction using the thallium-single photon emission computed tomography (SPECT) test and employing the technique of reinjection of the radioisotope 201Tl at rest. A study was conducted during the period of maximum stress, four hours and one hour after reinjection of 37 MBq of 201Tl. The presence and extent of reperfusion was determined. In addition, the incidence of ischaemia was correlated with four clinical parameters which might influence its occurrence: development period of the infarction (greater or less than 30 days), Q wave in the electrocardiogram, prior use of streptokinase, and angina. Twenty-seven patients exhibited partial reperfusion at rest which increased significantly in 14 of the patients after thallium reinjection. Moreover, 22 patients only exhibited reperfusion with reinjection. There was no relation between the clinical parameters evaluated and the incidence of ischaemia. In conclusion, with thallium reinjection 43% more patients can be detected with viable areas of myocardium which are not evident at rest. The clinical parameters evaluated are no help in predicting ischaemia with thallium. The routine use of reinjection is recommended to evaluate myocardial viability in patients with a history of infarction. (author). 14 refs, 2 figs

  9. Evaluation of malignancy and viability of brain tumors by 201Tl SPECT. The correlation between 201Tl SPECT and pathology, clinical progress and the intensity of enhancement on CT images

    International Nuclear Information System (INIS)

    Thallium-201 (201Tl) SPECT was performed 48 times in 26 patients to clarify its usefulness in the evaluation of malignancy and viability of brain tumors. The early counts ratio (ER) and delayed counts ratio (DR) of a lesion compared with normal brain were obtained 10-15 minutes and 3 hours, respectively, after intravenous administration of 185 MBq of 201Tl chloride. Untreated high grade malignant tumors and recurrent tumors did not always show high ER and DR, and they were widely distributed. High grade malignant tumors that showed low ER and DR were not well enhanced on CT or MRI. In low grade malignant tumors, such as pituitary adenoma which was well enhanced on CT, ER and DR were as high as in high grade malignant tumor. Whether a tumor recurred within three months after radiotherapy or not was retrospectively predicted as accuracy rates of 93.8% and 87.5% with cut-off points of 4.0 for ER and 3.5 for DR. Cerebral radiation necrosis showed ring-like increased uptake of 201Tl in proportion to the progress of necrosis and intensity of enhancement on MRI. In conclusion 201Tl SPECT is considered to be less useful for lesions that are well enhanced on CT, because they show high uptake of 201Tl regardless of their malignancy and viability. On the other hand, in tumors that are not well enhanced on CT, 201Tl shows good accumulation in viable and high grade malignant lesions. 201Tl SPECT should be lesions. 201Tl SPECT should be performed on such cases. (author)

  10. Estimation of Myocardial Ischemia by Diastolic Strain Analysis in Exercise Stress Echocardiography. Comparison with exercise thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    The feasibility of detecting persistent regional left ventricular abnormal relaxation due to myocardial ischemia using strain echocardiography several minutes after exercise was investigated. Consecutive 27 patients (mean age 65±9 years, 21 males, 6 females) with suspected coronary artery disease were enrolled. Strain echocardiographic images were acquired at the mid segments of the left ventricular wall before and 5 min after exercise in the apical long-axis, two-chamber and four-chamber views. Strain curves were obtained at each segment, and peak values of strain at the closure of aortic valve (A) and at one third of diastolic duration (B) were measured. Strain diastolic index (SDI) was calculated as (A-B)/A x 100%. The ratio of SDI before exercise to that after exercise was defined as the SDI ratio and compared with exercise thallium-201 single photon emission computed tomography (SPECT) as the reference standard to detect myocardial ischemia. A total of 162 segments were evaluated. Based on the results of exercise SPECT, 119 segments were classified as non-ischemic segments, and 43 as ischemic segments. Ischemic segments showed significant decreases in SDI before and after exercise, whereas non-ischemic segments showed no significant differences in SDI before and after exercise. SDI ratio was significantly decreased in ischemic segments, but not in non-ischemic segments. SDI ratio with a cut off value of 0.51 had a sensitivity of 91% and a specificity of 89% to dvity of 91% and a specificity of 89% to detect myocardial ischemia in the receiver-operating characteristics. Strain echocardiography can provide quantitative assessment of myocardial ischemia by detecting post-ischemic regional left ventricular delayed relaxation even 5 min after exercise. (author)

  11. Potential use of 201 Tl for the scintigraphic evaluation of acute irradiation lesion: experimental study in the pig

    International Nuclear Information System (INIS)

    201 Tl scintigraphy of lesions to thigh skin and muscle induced by overexposure to gamma rays was performed twice a week until day 48 post exposure on two groups of three pigs each, irradiated respectively with doses of 30 and 60 Gy. Tomoscintigraphy was performed once about day 120 after exposure and compared with pathologic findings. The use of 201 Tl was shown to be suitable for the survey of acute localized irradiations. Changes in thallium uptake were observed over the whole thigh and in the area irradiated. Four stages of change were distinguished and were found to correlate with the clinical evolution of lesion. This finding, combined with previous histological studies, enabled to conclude that 201 Tl uptake indicates vascular and cellular stages of inflammation. The possible origin of this uptake is discussed. After validation of the experimental model, indications of 201 Tl scintigraphy in the early and late stages of acute local irradiations in human are considered

  12. Evaluation of right ventricular overloading by 201Tl SPECT

    International Nuclear Information System (INIS)

    The present study evaluated the value of Tl-201 single photon emission computed tomography (SPECT) in the detection of right ventricular (RV) overloading. Twenty-three patients with RV pressure overloading (group P) and 17 with RV volume overloading (group V) underwent Tl-201 SPECT. RV/left ventricle (LV) Tl-201 uptake ratio (R/L-Tl) was calculated for quantitative analysis of RV overloading. Furthermore, RV/LV wall thickness ratio (R/L-WT) and RV/LV systolic pressure ratio (R/L-P) were calculated by magnetic resonance imaging and cardiac catheterization, respectively. Group V had a significantly dilated RV with clockwise rotation, as compared with Group P. There was a significantly positive correlation between R/L-Tl and R/L-WT in both Group P (Y=0.94X + 0.09, r=0.78) and Group V (Y=1.0X - 0.02, r=0.91). Positive correlation between R/L-Tl and R/L-P differed in Group P (Y=1.3X - 0.15, r=0.91) and Group V (Y=0.47X + 0.05, r=0.84). In conclusion, Tl-201 SPECT may be useful for detecting RV morphology in RV overloading patients, as well as estimating R/L-WT and R/L-P, by using R/L-Tl as a quantitative indicator. (N.K.)

  13. Effect of eating on thallium myocardial imaging

    International Nuclear Information System (INIS)

    To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The 201Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of 201Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed 201Tl images causes increased 201Tl myocardial clearance rates and may alter 201Tl myocardial redistribution over time

  14. Classification of 201TL and sup(99m)Tc-pertechnetate leg scan patterns and evaluation of their clinical significance

    International Nuclear Information System (INIS)

    Classification of the 201Tl and sup(99m)Tc-pertechnetate (sup(99m)TcOsub(4-)) leg scan patterns and their clinical significance were evaluated in the patients with ischemic diseases of the lower extremities (IDL) Five patterns were distinguished in both 201Tl and sup(99m)TcOsub(4-) leg scans; A: decreased activity throughout the affected leg, B: localized decreased activity in the affected leg, C: localized decreased activity associated with increased activity in the affected leg, D: generalized of localized increased activity in the affected leg and E: no laterality of the activity. 201Tl and sup(99m)TcOsub(4-) leg scan patterns were agreed in 55% of the patients. 201Tl leg scan had tendency to correlate the level of the vascular lesion in pattern B and C,However, diagnosis of the level of the lesion was difficult from the leg scan. Pattern D of the 201Tl leg scan was associated with increased blood flow in the affected leg on radionuclide angiography in 42% of the patients. After surgery, sup(99m)TcOsub(4-) leg scan tended to show pattern D, especially in the patients with lumbar sympathectomy. Patterns A, B and C were thought to suggest the ischemia. Patterns C and D were thought to express reactive hyperemia induced by the ischemic lesion. In the 60 preoperative IDL, sensitivity of 201Tl leg scan alone was 76% and that of combined use of 201Tl and sup(99m)TcOsub(4-) leg scans was 85%. Add sup(99m)TcOsub(4-) leg scans was 85%. Addition of radionuclide angiography increased sensitivity of IDL upto 98% and accuracy was 98%. Combined use of 201Tl and sup(99m)TcOsub(4-) leg scans and radionuclide angiography was useful for detection of IDL, and was also useful for evaluation of the results of the surgical intervention. (J.P.N.)

  15. Sympathetic reinnervation in cardiac transplants : preliminary results 123I-MIBG and 201Tl/99mTc-MIBI scintigraphy

    International Nuclear Information System (INIS)

    Iodine-123 metaiodobenzylguanidine (123I-MIBG) is a norepinephrine (NE) analogue. To determine whether cardiac sympathetic reinnervation occurs after orthotopic heart transplantation (TPL). Nine patients (M : F=7 :2; mean ages=34±24.1 yr; idiopathic:rheumatic = 8: 1) within 197.±14.3 (4-36) months after TPL performed both 123I-MIBG scintigraphy and 201Tl/99mTc-MIBI dipyridamole stress gated myocardial perfusion SPECT (g-MPS). 23I-MIBG imagings were performed in anterior position 15 minutes, 4 and 24 hours after i.v. injection of 148 MBq 123I MIBG. Image quantitation was based on the ratio of hear to mediastinal MIBG uptake (HMR). Six subjects with 123I-MIBG uptake on early 15. min imaging however, three subjects with 26 to 36(32.0±5.3) months had visible cardiac 123I-MIBG uptake (HMR:1.24±0.09 vs. 1.8±0.2). Correlation was found between plasma NE concentration and HMR(r=0.80: p1 years after TPL, as assessed by 123I-MIBG imaging

  16. 99Tcm-MIBI single photon emission tomography (SPET) for detecting myocardial ischaemia and necrosis in patients with significant coronary artery disease

    International Nuclear Information System (INIS)

    The ability of 99Tcm-methoxyisobutylisonitrile (MIBI) single photon emission tomography (SPET) to detect myocardial ischaemia and necrosis was assessed in 56 patients with clinically recognised ischaemic heart disease (IHD). All underwent coronary angiography (CA) and left ventriculography (LV). SPET images were obtained at rest and at peak exercise 90 min after injection of 99Tcm-MIBI. The presence of persistent (P) or reversible (R) perfusion defects (PD) was then correlated to the resting and exercise ECG and to the results of CA and LV. Of the 56 patients, 34 had reversible underperfusion (RPD), 46 persistent underperfusion (PPD) and 31 had both. The occurrence of RPD correlated well with the occurrence of exercise-induced ST segment depression and/or angina (27 patients of 34 patients, 79%) and with the presence of significant coronary artery disease (CAD) (33 of 44, 73%). In 45 of 46 patients (98%) PPD corresponded to akinetic or severely hypokinetic segments (LV) usually explored by ECG leads exhibiting diagnostic Q waves (42 of 46 patients, 91%). The scan was normal both at rest and after stress in four of 11 patients with no CAD, and in two of 45 patients with CAD. Finally, an abnormal resting scan was seen in seven of 11 patients with normal coronary arteries, of whom six had regional wall motion abnormalities. In conclusion, MIBI SPET is a highly reliable technique for assessing the presence and location of myocaressing the presence and location of myocardial ischaemia and necrosis. (Author)

  17. 201Tl-chloride thyroid scintigraphy to evaluate benign and/or malignant nodules: usefulness of the delayed scan

    International Nuclear Information System (INIS)

    The purpose of this study is to evaluate benign and/or malignant thyroid tumors with 201Tl thyroid scan. Researchers studied 76 cases of histologically verified thyroid tumors, all seen as cold nodules on the 123I thyroid scan. 201Tl thyroid scan was performed 5-15 minutes (early scan) and 3-5 hours (delayed scan) after intravenous administration of 1.5-2.0 mCi of 201Tl. In 35 (94.6%) of 36 malignant tumors (anaplastic carcinoma, six; papillary carcinoma 23; follicular carcinoma, five; epidermoid carcinoma, one; malignant lymphoma, 1) 201Tl accumulated in the cold nodule of the 123I thyroid scan on both early and delayed scans. On the other hand, the delayed 201Tl scan was negative in 35 out of 39 (89.7%) benign tumors. Employing early and delayed 201Tl scans, researchers were able to differentiate most malignant thyroid tumors from those which were benign. False-negative and -positive cases are discussed

  18. Thallium-201 myocardial SPECT findings at rest in sarcoidosis

    International Nuclear Information System (INIS)

    In 41 patients with sarcoidosis (diagnosed according to criteria recommended by the Committee on Diffuse Pulmonary Disease, Ministry of Health and Welfare, Japan 1988), thallium-201 (201Tl) myocardial SPECT was performed to investigate: the ability of 201Tl SPECT to detect cardiac involvement of sarcoidosis with images recorded at rest and 2 hours later, and the relationships between 201Tl myocardial SPECT findings and the activity of sarcoidosis or endomyocardial biopsy findings. As to the abnormal findings in 201Tl myocardial SPECT, a low density area was seen in 13 of 41 cases (31.7%) and non-uniform uptake was found in 17 cases (41.5%), the mean washout ratio (n=39) was 16.5±7.4%, which is significantly lower than that found in normal subjects, 23.9±7.5% (n=10). Of the 19 patients judged visually to be normal, 5 patients had a reduced mean washout ratio less than 12%. Thus, the incidence of abnormal findings including all types of abnormality in sarcoidosis was 63.4% (26/41 cases). As measured by the serum ACE (angiotensin converting enzyme) or lysozyme level, or the presence of more than 30% symphocyte fraction in BALF (broncho-alveolar lavage fluid), 20 (80%) of 25 cases with 201Tl abnormality were judged to be active sarcoidosis, while only 6 (37.5%) of 16 cases with normal findings on 201Tl SPECT were judged to be active. This suggest that there is a significant relationship between the presennificant relationship between the presence or absence of an abnormal finding on 201Tl myocardial SPECT and the activity of sarcoidosis. Among 13 patients examined by endomyocardial biopsy, 10 patients had abnormal findings on 201Tl myocardial SPECT and 7 of these 10 patients had no histological evidence of cardiac sarcoidosis. In all of these 7 patients, however, sarcoidosis was judged to be active. This suggest that endomyocardial biopsy is of limited value in the diagnosis of cardiac sarcoidosis. (author)

  19. Preparation and biodistribution of [201Tl](III)vancomycin complex in normal rats

    International Nuclear Information System (INIS)

    Thallium-201 (T1/2 = 3.04 days) in Tl+ form was converted to Tl3+ cation in presence of O3 in 6 M HCl controlled by RTLC/gel electrophoresis methods. The final evaporated activity was reacted with vancomycin (VAN) in water to yield [201Tl](III)VAN. The best results were obtained at room temperature in water after 30 min with a radiochemical yield >99%, after mixing the reactants followed by SPE purification using Si Sep-Pak. The studies showed that thallic ion is mostly incorporated into vancomycin with a radiochemical purity of more than 98 ± 1% by RTLC. A specific activity of about 4.14·1010 Bq/mmol was obtained. Radiochemical purity and stability of 201Tl-VAN in the preparation and in presence of human serum was determined up to 5.5 days. Biodistribution study of 201Tl(III)-vancomycin in normal rats was performed up to 52 h. (authors)

  20. False-positive defects in technetium-99m sestamibi myocardial single-photon emission tomography in healthy athletes with left ventricular hypertrophy

    International Nuclear Information System (INIS)

    Exercise ECG and myocardial single-photon emission tomography (SPET) are fundamental in the non-invasive evaluation of patients suspected of having coronary artery disease (CAD). The purpose of the present study was to investigate the influence of physiological left ventricular hypertrophy (LVH) on myocardial sestamibi SPET in healthy young and old athletes. Eighteen young male elite athletes (ten rowers, five power/weight lifters and three triathletes) and 14 well-trained elderly rowers were studied. All underwent a bicycle test as part of a 2-day sestamibi SPET protocol. Attenuation correction was not performed. The studies were evaluated visually and quantitatively analysed by the CEqual program with its reference files and with a file from a local non-athletic age-matched population. Echocardiographic LVH was an inclusion criterion in the young athletes. Exercise ECG was normal in all subjects. In at least three of the young athletes a reversible defect was observed by visual analysis. On quantitative analysis one-third of the young athletes had ''significant'' (>10 pixels) defects compared with both the local reference base and the CEqual reference population. Nearly all defects were found in the anterior or inferior wall. The remaining subjects, including all old rowers, had normal SPET findings. Anterior and inferior wall defects are so common in healthy athletes with physiological LVH that the specificity of myocardial SPET, in contrast to exercise ECG, seems SPET, in contrast to exercise ECG, seems to be too low for evaluation of chest pain in this group. The mechanism of anterior and inferior defects may be related to hot spots (papillary muscles?) in the lateral wall. The specificity of SPET is maintained in athletes without LVH. (orig.)

  1. Creation and characterization of Japanese standards for myocardial perfusion SPECT. Database from the Japanese Society of Nuclear Medicine Working Group

    International Nuclear Information System (INIS)

    Standards for myocardial single-photon emission computed tomography (SPECT) adapted for a Japanese population were not available. The purpose of this study was to create standard files approved by the Japanese Society of Nuclear Medicine and to make known the characteristics of the myocardial perfusion pattern of this population. With the collaboration of nine hospitals, a total of 326 sets of exercise-rest myocardial perfusion images were accumulated from subjects with a low likelihood of cardiac diseases. The normal database included a 99mTc-methoxyisobutylisonitrile (MIBI)/tetrofosmin myocardial perfusion study with 360 deg (n=80) and 180 deg (n=56) rotations, 201Tl study with 360 deg (n=115) and 180 deg rotations (n=54) and a dual-isotope study with 360 deg rotation (n=27). The projection images were transferred by digital imaging and communications in medicine (DICOM) format and reconstructed and analyzed with polar maps. The projection data from multiple centers were successfully transferred to a common format for SPECT reconstruction. When the average values were analyzed using a 17-segment model, myocardial counts in the septal segment differed significantly between 180 deg and 360 deg rotation acquisitions. Regional differences were observed between men and women in the inferior and anterior regions. A tracer difference between 99mTc and 201Tl was also observed in some segments. The attenuation patterns differed signts. The attenuation patterns differed significantly between subjects from the United States and those from Japan. Myocardial perfusion data that were specific for the Japanese population were generated. The normal database can serve a standard for nuclear cardiology work conducted in Japan. (author)

  2. Estimation of the lung uptake ratio of 201Tl in cardiopulmonary diseases

    International Nuclear Information System (INIS)

    On intravenous administration of 201TlCl (2-3mCi), the initial transit of it through the heart and lungs as well as subsequent uptake by the lung were recorded in the supine position using a scintillation camera coupling to a small digital computer. Leaving the patient in the same position the anterior image of perfusion lung scintigram with sup(99m)Tc-macroaggregated albumin or transmission scintigram with a point source of sup(99m)TcO4- taken. The radioactivity of total injected dosage (T) was calculated from the counts of the entire region on the initial transit of the tracer bolus through the heart and lungs, and counts per each pixel (E), total counts (L) and number of pixels (A) in the unilateral lung were calculated from the anterior image of 201Tl on which the isocount map of the perfusion lung scintigram or transmission one was superimposed. By these procedures, the uptake ratio of 201Tl per unilateral lung, the mean and each uptake ratio per pixel in the unilateral lung were calculated by L/T, L/T.A and E/T. Following results were obtained; 1) The mean value of the uptake ratio of it per unilateral lung in the right and left lung, were 1.5+-0.9%, 1.2+-0.6% in healthy lung; 3.2+-1.7%, 1.8+-1.0% in diffuse pulmonary diseases and 4.0+-1.6%, 2.5+-1.3% in cardiac diseases with left heart failure, respectively. 2) In the two groups using the perfusion lung scintigram and transmission one, the mean uptake rationd transmission one, the mean uptake ratio per pixel and number of pixels in the unilateral lung showed significant difference, but the uptake ratio per the unilateral lung did no significant difference. 3) These techniques are seemed to be useful for quantifying the lung uptake ratio of 201Tl on the lung scintigram with 201TlCl. (author)

  3. Significance of exercise-induced ST segment depression in patients with myocardial infarction involving the left circumflex artery. Evaluation by exercise thallium-201 myocardial single photon emission computed tomography

    International Nuclear Information System (INIS)

    The significance of exercise-induced ST segment depression in patients with left circumflex artery involvement was investigated by comparing exercise electrocardiography with exercise thallium-201 single photon emission computed tomography (Tl-SPECT) and the wall motion estimated by left ventriculography. Tl-SPECT and exercise electrocardiography were simultaneously performed in 51 patients with left circumflex artery involvement (angina pectoris 30, myocardial infarction 21). In patients with myocardial infarction, exercise-induced ST depression was frequently found in the V2, V3 and V4 leads. In patients with angina pectoris, ST depression was frequently found in the II, III, aVF, V5 and V6 leads. There was no obvious difference in the leads of ST depression in patients with myocardial infarction with ischemia and without ischemia on Tl-SPECT images. In patients with myocardial infarction, the lateral wall motion of the infarcted area evaluated by left ventriculography was more significantly impaired in the patients with ST depression than without ST depression (p<0.01). Exercise-induced ST depression in the precordial leads possibly reflects wall motion abnormality rather than ischemia in the lateral infarcted myocardium. (author)

  4. Effect of thallium-201 blood levels on reversible myocardial defects

    International Nuclear Information System (INIS)

    To determine if 201Tl plasma blood levels correlate with the presence of reversible myocardial defects during exercise testing, 14 patients with stable coronary artery disease underwent two separate exercise 201Tl stress tests. Between initial and delayed imaging, on one test the patients drank an instant breakfast drink (eating) and on the other they drank an equivalent volume of water as a control (H2O). Thallium-201 imaging was performed immediately postexercise, immediately after eating/H2O and 210 min after eating/H2O. Between initial and immediate post eating/H2O images 201Tl reversible defects occurred in 27/38 regions in the H2O test versus 15/38 regions in the eating test (p = 0.02). Over this early time period, plasma 201Tl activity was significantly higher in the H2O test than eating test (p less than 0.05). In conclusion, early reversal of 201Tl defects may, in part, be the result of higher plasma 201Tl activity early after initial postexercise 201Tl imaging

  5. Evaluation of technetium-99m-MIBI scintigraphy in metastatic differentiated thyroid cancer. Comparison study with 131I and 201Tl

    International Nuclear Information System (INIS)

    Detectability of metastasis in differentiated thyroid cancer using technetium-99m-methoxyisobutyl isonitrile (99mTc-MIBI) was compared with that of 131I and 201Tl. Forty patients after total thyroidectomy were evaluated. The scan results were compared with those of 131I and 201Tl whole body scintigraphy per patient. The positive rate was 68% in 99mTc-MIBI, 84% in 131I , 60% in 201Tl respectively. As to the lymph node metastasis, the positive rates were 56% in 99mTc-MIBI, 78% in 131I , 39% in 201Tl. In lung metastasis, the positive rate was 46% in 99mTc-MIBI, 82% in 131I and 55% in 201Tl. Serum thyroglobulin (Tg) was significantly higher in 201Tl and/or 99mTc-MIBI positive group compared to that of negative group independent of 131I scan results. Although the detectability of both 99mTc-MIBI and 201Tl were inferior to that of 131I , 9 to 22% of metastasis were detected only by these radiopharmaceuticals. Both 99mTc-MIBI and 201Tl, therefore, should be used in cases with high serum Tg even with negative 131I uptake. Basing on the fact there was no prominent difference between 99mTc-MIBI and 201Tl in the detectability of metastasis, 99mTc-MIBI might be more suitable tracer because of better be more suitable tracer because of better quality image. (author)

  6. Iodine-123 N-methyl-4-iododexetimide: a new radioligand for single-photon emission tomographic imaging of myocardial muscarinic receptors

    International Nuclear Information System (INIS)

    Cardiac muscarinic receptor ligands suitable for positron emission tomography have previously been characterised. Attempts to develop radioligands of these receptors suitable for single-photon emission tomographic (SPET) imaging have not been successful due to high lung retention and high non-specific binding of previously investigated potential tracers. The purpose of this study was to evaluate the biodistribution and in vivo imaging characteristics of a new radiopharmaceutical, [123I]N-methyl-4-iododexetimide. Biodistribution studies performed in rats showed high cardiac uptake (2.4% ID/g) 10 min after injection with a heart to lung activity ratio of 5:1. Specificity and stereoselectivity of cardiac binding were demonstrated using blocking experiments in rats. Dynamic imaging studies in anaesthetised greyhounds demonstrated rapid and high myocardial uptake and low lung binding with stable heart to lung activity ratios of >2.5:1 between 10 and 30 min, making SPET imaging feasible. Administration of an excess of an unlabelled muscarinic antagonist, methyl-quinuclidinyl benzylate rapidly displaced myocardial activity to background levels and the pharmacologically inactive enantiomer, [123I]N-methyl-4-iodolevetimide, had no detectable cardiac uptake, indicating specific and stereoselective muscarinic receptor binding. SPET revealed higher activity in the inferior than in the anterior wall, this being consistent with previously described regional vatent with previously described regional variation of cardiac parasympathetic innervation. [123I]N-methyl-4-iododexetimide shows promise as an imaging agent for muscarinic receptor distribution in the heart and may be helpful in evaluating diverse cardiac diseases associated with altered muscarinic receptor function, including heart failure and diabetic heart disease. (orig.)

  7. [Acute stent thrombosis and reverse transient left ventricular dilatation after performing a single-photon emission computed tomography myocardial perfusion].

    Science.gov (United States)

    Miranda, B; Pizzi, M N; Aguadé-Bruix, S; Domingo, E; Candell-Riera, J

    2015-01-01

    A 63-year-old male patient with a history of stent implantation in the left anterior descending three months before. Due to the presentation of vegetative symptoms, he was referred for gated-SPECT myocardial perfusion. During acquisition of the resting images he presented chest pain and ST segment elevation, so that urgent cardiac catheterization was performed, showing stent thrombosis. Rest perfusion imaging showed a defect in anterior and apical perfusion, more severe and extensive than in the stress images, with striking left ventricular dilatation and a fall in the ejection fraction related to the acute ischemia phenomenon. Intense exercise is associated with a transient activation of the coagulation system and hemodynamic changes that might induce thrombosis, especially in recently implanted coronary stents that probably still have not become completely endothelialized. PMID:25129322

  8. Medium- to long-term prognostic impact of dipyridamole thallium-201 myocardial single-photon emission computed tomography in elderly patients

    International Nuclear Information System (INIS)

    Dipyridamole thallium-201 single-photon emission computed tomography (SPECT) has not been extensively evaluated for risk stratification and the medium- to long-term prognostic value in elderly cardiac patients who are unable to exercise. The present study group comprised 210 consecutive patients aged at least 70 years with known or suspected coronary artery disease (CAD). The SPECT findings were classified as a reversible, fixed, or combined (reversible and fixed) defect. Of the 210 patients, 201 (77±5 years, 85 male) were successfully followed for 49±26 months. Thirteen (7%) patients had cardiac events: cardiac death (n=10), non-fatal myocardial infarction (n=1), or coronary artery bypass grafting (n=2). Cardiac events occurred in 3 of 112 patients with normal SPECT and in 10 of 89 patients with an abnormal scan (0.7%/year vs 2.8%/year, p=0.01). Stepwise Cox regression analysis revealed that the significant predictors of cardiac events were combined defects (relative risk 7.3) and the number of defect areas (relative risk 4.4). The predictive value of dipyridamole thallium-201 SPECT is maintained over 4 years in mixed populations of elderly CAD patients who are unable to exercise. (author)

  9. An experimental animal model of chronic myocardial hibernation: comparative study of cine-MR, myocardial single photon emission computed tomography and pathology

    International Nuclear Information System (INIS)

    Objective: To establish the chronic low-flow myocardial hibernation animal model in pigs, and to assess the diagnostic value for myocardial hibernation by using various imaging methods. Methods: A total of 13 miniswine (30-40 kg) were used. All animals underwent general anesthesia and orotracheal intubation while the animals were mechanically ventilated. Under sterile conditions, left ventriculography and coronary angiography were performed by introduction of catheter into the right femoral artery. Further, a left anterolateral thoracotomy was performed in the third intercostal space. The proximal LCX was dissected free to allow placement of an ameroid constrictor. More than 1 month later, left ventriculography and coronary angiography were performed again, followed by cine-MRI at rest and during stress with low-dose of dobutamine (5?g·kg-1·min-1), respectively. Traditional and/or breath-hold cine-MRI were used to evaluate regional left ventricular wall motion, corresponding to basal, midventricular and apical short-axis tomograms. Regional wall motion score index (WMSI) was calculated. At the same time 99mTc-MIBI myocardial SPECT was performed at rest and during nitroglycerin administration, respectively. All animals were finally sacrificed for pathological examination. Triphenyl tetrazolium chloride (TTC) staining was used to assess the myocardial infarction. Electron microscopy was used to identify myocardial cellular changes chadentify myocardial cellular changes characteristic of hibernating myocardium. Results: Three pigs died during surgery or within two weeks after surgery. One pig died of anesthesia during SPECT examination, 1 pig suffered from aneurysm, and another one pig showed negative findings. The other 7 pigs were found with hypokinetic (n=4) or akinetic (n=3) myocardial regions related to stenosed LCX (70%-99%). Resting cine-MRI demonstrated decreased regional motion of the lateral and posteroinferior walls (ischemic regions) of the left ventricle (n=7), compared with the nonischemic anteroseptal regions; but the low dose dobutamine (5?g·kg-1·min-1) could recover those hypokinetic or akinetic myocardial regions, characteristic of hibernating myocardium. Resting 99mTc-MIBI myocardial SPECT (n=6) showed a fixed perfusion defect on the corresponding ischemic areas, which became reversible on the nitrate-augmented myocardial perfusion imaging. It also indicated myocardial viability presented at the ischemic areas. TTC staining revealed patchy infarction of the area-at-risk localized to the endocardial surface (n=3), and no myocardial infarction (n=4). Electron microscopy of sections from the hibernating regions revealed loss of contractile materials, increased numbers of small mitochondria, and glycogen accumulation within viable cardiomyocytes, which had been described as hallmarks of hibernating myocardium. Conclusion: Chronic low-flow myocardial hibernation can be reproduced in an animal model during progressive coronary stenosis caused by ameroid constrictor

  10. Removal of {sup 99m}Tc and {sup 201}Tl by means of Lemna Gibba; Remocion de {sup 99m}Tc y {sup 201}Tl mediante Lemna Gibba

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez R, E.; Carreno de L, M. C.; Cuevas S, J. C.; Hernadez T, U. O. [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Fraccionamiento La Virgen, 52149 Metepec, Estado de Mexico (Mexico); Monroy G, F., E-mail: edelmiraf@yahoo.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    In this work the capacity of the water macrophyte Lemna gibba coming from San Pedro Tultepec in the Mexico State was studied to remove the radioisotopes {sup 99m}Tc and {sup 201}Tl, in order to show the capacity of this macrophyte for to treat some radioactive waste flowing that could contain this radioisotopes type. The removal capacity of {sup 99m}Tc and {sup 201}Tl of the macrophyte Lemna gibba was determined using the batch method. In accordance with the values of the obtained K{sub d}, the Lemna gibba with a size of particle diameter among 1mm - 300 {mu}m presents a better adsorption of {sup 99m}Tc. The {sup 201}Tl is adsorbed better in the bioadsorbent when it has a size of particle diameter <150{mu}m. (Author)

  11. Evaluation of 201TlCl per rectum scintigraphy in biliary atresia

    International Nuclear Information System (INIS)

    To study whether or not 201TlCl per rectum scintigraphy is clinically useful for evaluating portosystemic shunt in biliary atresia (BA), we reviewed 13 patients with biliary atresia already in the postoperative state. The patients' details were as follows: age, 4 years 6 months-18 years 7 months (mean: 12 years 7 months); male, 3 cases; females, 10 cases; type III BA, 11 cases; type I-cyst BA, 2 cases. A radioisotope (RI) of 201TlCl (18.5 or 37.0 MBq) was administered via the rectum. Heart and liver counts per area were calculated respectively 30-60 minutes after RI administration, and the ratio of heart and liver (H/L ratio) was adopted as a indicator of portosystemic shunt. There was no correlation between the H/L ratio and laboratory examinations (total bilirubin, alanine aminotransferase, cholinesterase, white blood cell and platelet). There was positive correlation between the H/L ratio and splenomegaly. Splenomegaly was evaluated using gray-scale ultrasonography. There was a positive correlation between the H/L ratio and existence of esophageal varices. Esophageal varices were evaluated using barium meal upper gastrointestinal examination. There was a remarkable positive correlation between the H/L ratio and the patient's age. This group of patients was restricted to that in which the laboratory liver function test was abnormal. The use of 201TlCl via rectum scintigraphy and quantitatively conducted H/L ratio are clinically usefuy conducted H/L ratio are clinically useful for evaluating the portosystemic shunt in biliary atresia. The portosystemic shunt might gradually increase with patients' age independently of the liver function, which should support our daily clinical observations. (author)

  12. Initial multicentre experience of high-speed myocardial perfusion imaging: comparison between high-speed and conventional single-photon emission computed tomography with angiographic validation

    Energy Technology Data Exchange (ETDEWEB)

    Neill, Johanne [University College London Hospital, Institute of Nuclear Medicine, London (United Kingdom); The Prince Charles Hospital, Brisbane (Australia); Prvulovich, Elizabeth M.; Bomanji, Jamshed B. [University College London Hospital, Institute of Nuclear Medicine, London (United Kingdom); Fish, Matthews B. [Sacred Heart Medical Center (SHMC), Springfield, OR (United States); Berman, Daniel S.; Slomka, Piotr J. [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Sharir, Tali [Procardia Maccabi Healthcare Services (PMHS), Tel Aviv (Israel); Martin, William H. [Vanderbilt University Medical Center (VUMC), Nashville, TN (United States); DiCarli, Marcelo F. [Brigham and Women' s Hospital (BWH), Boston, MA (United States); Ziffer, Jack A. [Baptist Hospital of Miami (BHM), Miami, FL (United States); Shiti, Dalia [Spectrum-Dynamics, Caesarea (Israel); Ben-Haim, Simona [University College London Hospital, Institute of Nuclear Medicine, London (United Kingdom); Chaim Sheba Medical Center, Department of Nuclear Medicine, Tel-Hashomer (Israel)

    2013-07-15

    High-speed (HS) single-photon emission computed tomography (SPECT) with a recently developed solid-state camera shows comparable myocardial perfusion abnormalities to those seen in conventional SPECT. We aimed to compare HS and conventional SPECT images from multiple centres with coronary angiographic findings. The study included 50 patients who had sequential conventional SPECT and HS SPECT myocardial perfusion studies and coronary angiography within 3 months. Stress and rest perfusion images were visually analysed and scored semiquantitatively using a 17-segment model by two experienced blinded readers. Global and coronary territorial summed stress scores (SSS) and summed rest scores (SRS) were calculated. Global SSS {>=}3 or coronary territorial SSS {>=}2 was considered abnormal. In addition the total perfusion deficit (TPD) was automatically derived. TPD >5 % and coronary territorial TPD {>=}3 % were defined as abnormal. Coronary angiograms were analysed for site and severity of coronary stenosis; {>=}50 % was considered significant. Of the 50 patients, 13 (26 %) had no stenosis, 22 (44 %) had single-vessel disease, 6 (12 %) had double-vessel disease and 9 (18 %) had triple-vessel disease. There was a good linear correlation between the visual global SSS and SRS (Spearman's {rho} 0.897 and 0.866, respectively; p < 0.001). In relation to coronary angiography, the sensitivities, specificities and accuracies of HS SPECT and conventional SPECT by visual assessment were 92 % (35/38), 83 % (10/12) and 90 % (45/50) vs. 84 % (32/38), 50 % (6/12) and 76 % (38/50), respectively (p < 0.001). The sensitivities, specificities and accuracies of HS SPECT and conventional SPECT in relation to automated TPD assessment were 89 % (31/35), 57 % (8/14) and 80 % (39/49) vs. 86 % (31/36), 77 % (10/13) and 84 % (41/49), respectively. HS SPECT allows fast acquisition of myocardial perfusion images that correlate well with angiographic findings with overall accuracy by visual assessment better than conventional SPECT. Further assessment in a larger patient population may be needed to confirm this observation. (orig.)

  13. Myocardial perfusion assessed by contrast echocardiography and single photon emission computed tomography in the evaluation of patients with acute chest pain and normal electrocardiogram

    International Nuclear Information System (INIS)

    Aim : Evaluation of diagnostic accuracy of myocardial contrast echocardiography (MCE) in comparison with single-photon emission computed tomography (SPECT) for the detection of myocardial ischemia in patients with acute chest pain. Material and Methods : Eighteen patients (pts) with chest pain lasting ?30 minutes, occurring within 6 hours of emergency room presentation and a normal or no diagnostic electrocardiogram were studied. Pts underwent rest MCE and SPECT. For both exams myocardial perfusion was assessed in the same 7 segments (apical, anterior, inferior, anteroseptal, inferoseptal, lateral and posterior) of left ventricle. A total of 126 segments were analyzed. Images were classified as positive for ischemia if they had a perfusion defect. Coronary angiography was performed if MCE or SPECT images were classified as positive for ischemia or by clinical indication. Otherwise the patients underwent stress SPECT. Significant coronary artery disease (CAD) was defined as ?70% stenosis in a major coronary artery or its branches. Final diagnosis of an acute coronary event (ACE) was established in the presence of positive findings in MCE or SPECT in addition to significant CAD in the corresponding territory. Kappa statistics were calculated to evaluate the concordance between MCE and SPECT. ? values of ?0.4, >0.4 and >0.7 indicate fair, good and excellent agreement, respectively. Results: Thirteen out of 18 pts underwent coronary angiography (seven pts had positry angiography (seven pts had positive findings on SPECT, 2 on MCE, 2 on both exams and 1 had clinical indication). Significant CAD was detected on six. Five pts underwent stress SPECT and no perfusion defect was detected. Therefore, six pts (33.3%) had an ACE and 12 (66.6%) had not. There were no statistical differences between groups according to age, gender, duration of pain, free pain interval, presence of risk factors and antecedents. Concordance between MCE and SPECT for evaluation of perfusion defects showed a ? coefficient of 0.04. Sensitivity, specificity, negative and positive predictive values for SPECT were, respectively, 100%, 75%, 100% and 60%. For MCE these values were, respectively, 20%, 76%, 71.4% and 50%. Conclusion: SPECT demonstrated to be a reliable technique in the discrimination of patients with an ACE among those who were admitted with acute chest pain at emergency room. MCE was less useful in this setting

  14. Parathyroid localizlation by 201Tl-99mTc subtraction scintigraphy

    International Nuclear Information System (INIS)

    Subtraction scintigraphy with 201Tl and 99mTc for parathyroid localization was performed preoperatively in 13 patients with chronic renal failure and secondary hyperparathyroidism. Twenty of the 37 examined pathological glands were predicted correctly (sensitivity 54%). In 3 patients with recurrent hyperparathyroidism after surgery all pathological glands found at second operation had been detected correctly by subtraction scintigraphy. We conclude that this localization method has a limited value when used prior to first neck exploration in secondary hyperparathyroidism. In persistent hyperparathyroidism after surgery it may play a useful role in localizing missed and ectopic glands. (author)

  15. Parathyroid localizlation by sup 201 Tl- sup 99m Tc subtraction scintigraphy; Results in secondary hyperparathyroidism

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    Rademaker, P. (Department of Internal Medicine, University Hospital, Groningen (Netherlands)); Meijer, S. (Division of Nephrology, University Hospital, Groningen (Netherlands)); Piers, D.A. (Department of Nuclear Medicine, University Hospital, Groningen (Netherlands))

    1990-01-01

    Subtraction scintigraphy with {sup 201}Tl and {sup 99m}Tc for parathyroid localization was performed preoperatively in 13 patients with chronic renal failure and secondary hyperparathyroidism. Twenty of the 37 examined pathological glands were predicted correctly (sensitivity 54%). In 3 patients with recurrent hyperparathyroidism after surgery all pathological glands found at second operation had been detected correctly by subtraction scintigraphy. We conclude that this localization method has a limited value when used prior to first neck exploration in secondary hyperparathyroidism. In persistent hyperparathyroidism after surgery it may play a useful role in localizing missed and ectopic glands. (author).

  16. Acute myocardial infarction

    International Nuclear Information System (INIS)

    To evaluate the extent and characteristics of infarct areas, we performed indium-111 monoclonal antimyosin Fab (InAM), thallium-201 (TL) and Tc-99m pyrophosphate (PYP) imagings in 17 patients with acute myocardial infarction, and tried to find out the mechanism that causes difference of these imagings. In each study, the extent scores as an index of the infarct area were obtained by single photon emission computed tomography (SPECT), and comparisons were made between the results obtained. The overlap between InAM and TL imagings obtained by SPECT was evaluated. Location, severity, extent and patterns of accumulation were compared between InAM and PYP with both planar image and SPECT. The extent scores of InAM correlated well with those of TL (r=0.73, p<0.01). However, the overlap of both methods was recognized in 8 of 17 patients, in whom wall thickness of the infarct area as obtained by echocardiography was well preserved. The left ventricular regional asynergy was mild in 6 of these 8 patients. Coronary angiography showed poor or no collateral circulation in these cases. Although there were generally close correlations of the extent scores between InAM and PYP, discrepancy was noted in 2 cases for location; 2 for severity, 5 for extent, and 3 for patterns of accumulation. These differences may be attributed to the timings of imaging, coronary reperfusion and different mechanisms of accumulation. In conclusion, the extent of acute myocardial infarction obtained by Inacute myocardial infarction obtained by InAM correlates well with those obtained by TL and PYP, with some exceptions. (author)

  17. Detection of myocardial viability by means of Single Proton Emission Computed Tomography (Perfused SPECT) dual 201 Tl (rest of 15 minutes, 24 late hours and 24 hours reinjection) and gated-SPECT 99m Tc-SESTAMIBI in effort or stimulation of the coronary reserves

    International Nuclear Information System (INIS)

    The objective of this work was to determine if the images of SPECT 201 TI in rest of 15 minutes, 24 late hours and Gated-SPECT 99m Tc-SESTAMIBI in effort or stimulation of coronary reservation correlate with the study of 24 hours post reinjection of 201TI to determine the presence of having knitted viable myocardium. Material and methods: 29 patients were studied with coronary arterial illness (EAC) to who are carried out SPECT 201 TI in rest with images of 15 minutes, 24 late hours and 24 hours reinjection, by means of the administration of 201TI to dose of 130 MBq and reinjection with 37 MBq. and Gated-SPECT 99mTc-SESTAMIBI in effort or stimulation of coronary reservation, later to the administration of 1110 MBq. Results: 29 patients were included according to inclusion approaches and exclusion, of those which 22 (75.86%) they correspond at the masculine sex and 7 (24.13%) to the feminine one, with an average of 62.1 year-old age, 2320 segments myocardial were analysed so much it is phase post-effort as rest; they were diagnosed a total of 264 segments with heart attack, of which viability myocardium was observed in 174 segments. The statistical tests are analysis of frequencies. The non parametric test of Wilcoxon and Mann-Whitney. Conclusions: the viability myocardial at the 24 late hours and 24 hours reinjection was similar; significant difference exists between the study of 15 minutes and 24 hourstween the study of 15 minutes and 24 hours reinjection, ischemic illness was also demonstrated in territories different to the heart attack area in the studies of 15 minutes, late 24 hours and 24 hours reinjection. (Author)

  18. Regional myocardial N-13-glutamate uptake in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Twenty patients suffering from coronary single-vessel disease (10 with previous myocardial infarction) underwent cardiac catheterization, 201Tl serial scintigraphy, and 13N-glutamate scintigraphy. Both 201Tl scintigraphy (5 min and 3 hrs p.i.) and 13N-glutamate scintigraphy were performed in thea LAO 300 projection following submaximal exercise. Regional tracer uptake was quantified by computer assisted placement of regions of interest within the myocardium. In myocardial segments with exercise-induced ischemia - indicated by an initially decreased 201Tl uptake and subsequent redistribution within 3 hrs - regional 13N-glutamate uptake was increased, either relatively compared to the same region in the post stress 201Tl scintigram, or even absolutely compared to non-ischemic segments within the respective scintigram. This discordant pattern between 201Tl and 13N-glutamate scintigrams was not obtained in patients with previous transmural myocardial infarction: both regional 13N-glutamate and 201Tl uptake were decreased below normal limits. Moreover, the decrease in 13N-glutamate uptake was closely related to the impairment of left ventricular wall motion as assessed by contrast angiography. The data suggest the clinical usefulness of 13N labeled glutamate as an indicator of myocardial viability in patients suffering frcardial viability in patients suffering from coronary artery disease. (Author)

  19. Studies on muscle metabolism in peripheral vascular disease using 201Tl

    International Nuclear Information System (INIS)

    Thallium 201 has been used mostly in cardiology, for the detection of ischemic ''areas'' and infarcted zones in cardiac muscle. This isotope has been chosen, because of its great metabolic similarity to Potassium. But less interest has been shown in the transit and localization of Thallium in the limbs. We have been working on a method based upon the study of muscle metabolism using 201Tl which could possibly detect the condition before the onset of clinical symptoms. As a preliminary investigation, we have studied the distribution of this isotope, in rats after effort, or in resting state. We have observed an important increase in the muscle uptake of 201Tl during the period of effort compared to the uptake in a resting state. The ratio of this increased uptake is about two to three times more important. In vitro studies of fibroblast cell cultures reveal a competition between potassium and thallium, the fixation of thallium being diminished in the presence of an excess of potassium and increased when the concentration of potassium is low, in the culture medium

  20. SPECT imaging of hypertrophic cardiomyopathy with 201Tl and 123I-MIBG

    International Nuclear Information System (INIS)

    Objective: The aim of this study is to clarify whether there are differences in sympathetic nerve activities between hypertrophied and non-hypertrophied myocardium in patients with hypertrophic cardiomyopathy (HCM). Methods:18 patients with HCM diagnosed with symptomatology and echocardiography and six normal subjects underwent two-dimensional and M-mode echocardiography, and SPECT with 201Tl and 123I-MIBG. The HCM group included 5 of apical type (APM), 7 of asymmetrical septal hypertrophy (ASH) and 6 of defused type (DPM). The average age of HCM group was (56.8 +-8.8) years, and normal group, 49.0 +- 5.4. Results: In 201Tl study, there was no difference between HCM and normal group. In 123I-MIBG study, HCM group showed low radioactivities compared with normal group (P123I-MIBG scanning in HCM group, APM and DPM type showed low activities in anterior (P123I-MIBG activities, mild hypertrophy group showed low activities as well as marked hypertrophy group did (P<0.01, P<0.01). Conclusion: The patients with HCM still can maintain normal blood flow in per unit myocardium, even though they showed decreased sympathetic nerve activities in the hypertrophied as well as non-hypertrophied myocardiumrophied myocardium

  1. A noninvasive method for evaluating portal circulation by administration of 201Tl per rectum

    International Nuclear Information System (INIS)

    A new method for evaluating portal systemic circulation by administration of 201Tl per rectum was performed in 13 control subjects and in 65 patients with various liver diseases. In normal controls, the liver was visualized on the 0--5-min image whereas the images of other organs such as the heart, spleen, and lungs were very poor. In patients with liver cirrhosis associated with portal-systemic shunt, and in many other patients with hepatocellular damage, the liver was not so clearly visualized, whereas radioactivity in other organs, especially the heart, became evident. The heart-to-liver uptake ratio at 20 min after administration (H/L ratio) was significantly higher in liver cirrhosis than in normals and patients with chronic hepatitis (p less than 0.001). The patients with esophageal varices showed a significantly higher H/L ratio compared with that in cirrhotic patients without esophageal varices (p less than 0.001). The H/L ratio also showed a significant difference (p less than 0.01) between Stage 1 and Stage 3 esophageal varices. Since there were many other patients with hepatocellular damage who had high H/L ratios similar to those in liver cirrhosis, the effect that hepatocellular damage has on the liver uptake of 201Tl is also considered. Our present data suggest that this noninvasive method seems to be useful in evaluating portal-to-systemic shunting

  2. Sequential change of SPECT using 201Tl chloride during the treatment of intracranial gliomas

    International Nuclear Information System (INIS)

    The authors followed up the change in SPECT using 201Tl chloride (Tl-SPECT) according to the course of treatment of intracranial gliomas and analyzed the difference in Tl-SPECT between the stable and progressive groups. The subjects were 26 series of supratentorial gliomas subjected to Tl-SPECT before and after the treatment (radiotherapy and chemotherapy). They were put on Tl-SPECT after 10 minutes (early image) and 4 hours (delayed) following intravenous injection of 74 MBq of 201Tl. Besides, RI count ratio (L/N) in the tumor lesion (L) to the contralateral parenchyma (N) was measured. The patients were divided into stable and progressive groups judging from the therapeutic efficacy. The change in L/N ratio before and after the treatment was analysed. The stable group showed a significant post-treatment decrease in L/N ratio compared with a significant post-treatment increase for the progressive group. This suggested that Tl-SPECT would change according to the course of treatment and aid in the therapeutic judgement in gliomas. (author)

  3. Use of 123I-BMIPP single-photon emission tomography to estimate areas at risk following successful revascularization in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    Previous studies have indicated that iodine-123 labelled ?-methyliodophenyl pentadecanoic acid (BMIPP), an iodinated fatty acid analogue, can identify persistent alteration of fatty acid metabolism after restoration of blood flow. To assess whether fatty acid imaging can delineate areas at risk following successful revascularization in patients with acute myocardial infarction (AMI), BMIPP findings at 1 week post AMI were compared with perfusion imaging before and after revascularization therapy. Sixty-five patients with AMI underwent technetium-99m tetrofosmin single-photon emission tomography (SPET) before m (TF0) and 1 week (TF1) after successful revascularization therapy. BMIPP SPET was also performed under a fasting state at 1 week (BM1) post AMI. The extent scores were calculated from the defect scores in 20 segments. The BM1 score (7.7±3.9) was similar to the TF0 score (8.8±4.2) (r=0.86, P<0.0001), but significantly higher than the TF1 score (5.8±3.9) (P<0.0001). A significant correlation was observed between the BM1 score and TF0 score (r=0.86, P<0.0001). Among a total of 1300 segments, the BM1 score was identical to the TF0 score in 1156 (88.9%). These data indicate that the ability of BMIPP imaging at 1 week post AMI to identify areas at risk is similar to that of tetrofosmin perfusion imaging in the acute phase. This may be due to the impairment of fatty acid uptake and metabolism reflecting prior severe ischaemic insult which persists at least 1 week ansult which persists at least 1 week after recovery of perfusion in the acute phase of AMI. (orig.)

  4. Study to prepare 201Tl by irradiation of mercury with protons. Application of extraction chromatography technique in separation of thallium and mercury

    International Nuclear Information System (INIS)

    The extraction chromatography technique was used for the lig and 201Tl separation. It was used glass columns of 5,0 cm height and 1,0 cm diameter filled with Voltalef powder impregnated with TBP/cyclohexane. By the Voltalef columns solutions of 203Hg2+, 201Tl1+ and 201Te3 were separately percolated in a nitric environment of 4 to 8 M concentration and in a hydrochloridric environment of 0,5 to 4 M. The separation of Hg and 201Tl was obtained by the retention of 201Tl3+ in the column during the elution of all the Hg with HCl 2 M. The 201Tl3+ was eluted from the column after its reduction with a hot hydrazine dichloride solution. (Author)

  5. Fast washout of thallium-201 from area of myocardial infarction: possible artifact of background subtraction

    International Nuclear Information System (INIS)

    A recent report described a pattern of reverse redistribution on poststreptokinase 201Tl studies which was believed to be due to rapid washout of 201Tl from the infarct area related to reperfusion of the infarct vessel. We have also observed the phenomenon of rapid washout of 201Tl from the area of infarction in the absence of thrombolytic therapy. This study was undertaken to test the hypothesis that rapid washout of 201Tl from an area of infarction is an artifact of background subtraction usually employed in analysis of washout. A total of 61 patients with previous myocardial infarction who underwent cardiac catheterization and exercise 201Tl imaging were examined. Thallium-201 images were analyzed using a validated quantitative method employing interpolative background correction. Abnormally increased 201Tl washout was noted in 11 infarct segments in 10 (18%) patients. Infarct segments with rapid washout had significantly less initial uptake, and more severe associated wall motion abnormalities than infarct segments with normal washout. When quantitative analysis was repeated without background subtraction, no segments with rapid washout were observed. A phantom model was constructed to further test our hypothesis. The frequency of observed rapid washout was directly related to the severity of the initial defect and was entirely dependent upon utilizing background correction during the quantitative around correction during the quantitative analysis. Our study suggests that rapid washout of 201Tl in an area of previous infarction reflects an artifact of background subtraction involved with standard quantitative analysis

  6. Usefulness of 99mTc-methoxy-iso-butyl-isonitrile myocardial single photon emission computed tomography during infusion of low-dose dobutamine and nitroglycerin. Evaluation of myocardial viability

    International Nuclear Information System (INIS)

    This study evaluated myocardial viability with 99mTc-methoxy-iso-butyl-isonitrile (MIBI) single photon emission computed tomography (SPECT) during infusion of low-dose of dobutamine (DOB) and nitroglycerin (NTG). The subjects were 13 patients with coronary artery disease associated with wall motion abnormalities. Myocardial SPECT with MIBI was performed during infusion of NTG followed by infusion of DOB. Rest MIBI study was also performed on a separate day. The regional uptake of MIBI was visually evaluated by scoring (from 0=normal to 3=defect) in 9 regions of left ventricular wall in comparison with LVG or echocardiography data. The regional uptake of MIBI was quantitatively evaluated in 33 segments of left ventricular wall by a computer. The uptake of MIBI during infusion of both DOB and NTG was compared with that at rest study in the region of wall motion abnormalities. The mean uptake score of MIBI during infusion of both DOB and NTG and that of MIBI at rest was 1.8 and 2.1, respectively. The uptake of MIBI was significantly improved by infusion of both DOB and NTG (p<0.01). Percent of the peak activity of MIBI during infusion of both DOB and NTG and that of MIBI at rest in the region where the uptake score had been improved was 76.6±12.7% versus 74.0±13.1% (p<0.01). Percent of the peak activity of MIBI in the region where the uptake score had not been improved was 60.1±18.1% versus 60.7±18.7% (NS). Quantitative study also showed a significant impre study also showed a significant improvement of MIBI uptake on the study of DOB and NTG. These results suggest that MIBI SPECT during infusion of both DOB and NTG infusion might be useful for evaluating myocardial viability. (S.Y.)

  7. The value of gallium-67 and thallium-201 whole-body and single-photon emission tomography images in dialysis-related {beta}{sub 2}-microglobulin amyloid

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    Yen Tzuchen; Tzen Kaiyuan [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Taipei Medical Center and School of Medicine, Chang Gung University (Taiwan); Chen Kuosu; Tsai Chijuen [Dept. of Nephrology, Chang Gung Memorial Hospital at Keelung (Taiwan)

    2000-01-01

    The aim of this study was to investigate the value of gallium-67 and thallium-201 whole-body and single-photon emission tomography (SPET) images in long-term dialysis patients in whom dialysis-related {beta}{sub 2}-microglobulin amyloid ({beta}{sub 2}-MA) was clinically suspected. Twenty-three patients who had received dialysis for at least 10 years were included in the study. A technetium-99m methylene diphosphonate (MDP) whole-body scan was performed in all of the patients. If there was any MDP accumulation in the articular and/or peri-articular region, {sup 67}Ga and {sup 201}Tl whole-body and SPET images were then acquired. If any {sup 67}Ga and/or {sup 201}Tl uptake was observed, a CT-guided biopsy was done. In those patients who had articular and/or peri-articular uptake of {sup 99m}Tc MDP, {sup 67}Ga and/or {sup 201}Tl and who were pathologically proven to have {beta}{sub 2}-MA, {sup 99m}Tc MDP, {sup 67}Ga and {sup 201}Tl whole-body scans and SPET were carried out again, both 3 months and 1 year after initiation of treatment. This served to evaluate the therapeutic effect and allowed comparison with the clinical findings. Of the 23 patients, eight had abnormal {sup 99m}Tc MDP uptake. Among these eight, six had intense {sup 99m}Tc MDP, {sup 67}Ga and {sup 201}Tl uptake in the articular and peri-articular regions before medication. Three months after the start of treatment, there were very marked decreases in uptake on both the {sup 67}Ga and {sup 201}Tl scans but less obvious changes in uptake of {sup 99m}Tc-MDP. In comparison with the other clinical manifestations such as limitation in range of motion, the more the painful disability improved, the less was the uptake on both {sup 67}Ga and {sup 201}Tl scans. There were virtually no differences in uptake pattern between the three scans of each radiopharmaceutical obtained for each patient in both 3 months and 1 year after initial of treatment. It is concluded that {sup 99m}Tc-MDP whole-body bone scan can both detect active and pre-existing inactive deposits of {beta}{sub 2}-MA. {sup 67}Ga and {sup 201}Tl scans are helpful to differentiate active from inactive deposits of {beta}{sub 2}-MA and to evaluate the therapeutic effect on these patients. SPET images are usually needed to distinguish articular and peri-articular lesions from bone lesions. (orig.)

  8. Therapeutic effects of coenzyme Q10 on dilated cardiomyopathy. Assessment by 123I-BMIPP myocardial single photon emission computed tomography (SPECT). A multicenter trial in Osaka University Medical School Group

    International Nuclear Information System (INIS)

    To evaluate therapeutic effects of Coenzyme Q10 (CoQ10), 15 patients with dilated cardiomyopathy were investigated by 123I-BMIPP myocardial single photon emission computed tomography (SPECT). The BMIPP defect score was determined semiquantitatively by using representative short and long axial SPECT images. Mean BMIPP defect score with CoQ10 treatment was significantly low, 7.7±6.1 compared to 12.7±7.4 without CoQ10 treatment. On the other hand, in 8 patients of dilated cardiomyopathy, % fractional shortening using echocardiography was not different before and after CoQ10 treatment. In conclusion, 123I-BMIPP myocardial SPECT was proved to be sensitive to evaluate the therapeutic effects of CoQ10, which improve myocardial mitochondrial function, in the cases of dilated cardiomyopathy. (author)

  9. Therapeutic effects of coenzyme Q10 on dilated cardiomyopathy. Assessment by {sup 123}I-BMIPP myocardial single photon emission computed tomography (SPECT). A multicenter trial in Osaka University Medical School Group

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    Nishimura, Tsunehiko; Hori, Masatsugu [Osaka Univ. (Japan). Faculty of Medicine

    1996-01-01

    To evaluate therapeutic effects of Coenzyme Q10 (CoQ10), 15 patients with dilated cardiomyopathy were investigated by {sup 123}I-BMIPP myocardial single photon emission computed tomography (SPECT). The BMIPP defect score was determined semiquantitatively by using representative short and long axial SPECT images. Mean BMIPP defect score with CoQ10 treatment was significantly low, 7.7{+-}6.1 compared to 12.7{+-}7.4 without CoQ10 treatment. On the other hand, in 8 patients of dilated cardiomyopathy, % fractional shortening using echocardiography was not different before and after CoQ10 treatment. In conclusion, {sup 123}I-BMIPP myocardial SPECT was proved to be sensitive to evaluate the therapeutic effects of CoQ10, which improve myocardial mitochondrial function, in the cases of dilated cardiomyopathy. (author).

  10. Myocardial infarction

    International Nuclear Information System (INIS)

    sup(99m)Tc-pyrophosphate (PYP) scintigraphy and 201Tl myocardial scintigraphy were utilized for the diagnoses of the presence, the region, and the extent of myocardial infarction. Exercise 201Tl myocardial scintigrams and exercise radionuclide ventriculography were utilized for diagnosis of coronary artery lesions in angina pectoris. Radionuclide ventriculography was used to investigate effects of coronary artery lesions on cardiac function and hemodynamics. In order to select adequate treatments for myocardial infarction and estimate the prognosis, it was necessary to detect the presence, the region, and the extent of acute myocardial infarction and to investigate effects of partial infarction on hemodynamics by using radionuclide imaging. Exercise myocardial scintigraphy could be carried out noninvasively and repeatedly for diagnosis of coronal artery disease. Therefore, this method could be applied widely. It was possible to use this method as a screening test of coronary artery diseases for the diagnoses of asymptomatic patients who showed ST changes in ECG, the patients with cardiac neurosis and the patency after a reconstructive surgery of coronary artery. (Tsunoda, M.)

  11. Thallium-201 gated single-photon emission tomography for the assessment of left ventricular ejection fraction and regional wall motion abnormalities in comparison with two-dimensional echocardiography

    International Nuclear Information System (INIS)

    Simultaneous assessment of myocardial perfusion and function by gated single-photon emission tomography (GS) after a single tracer injection provides incremental information and is feasible with technetium-99m sestamibi. The present study validated the use of GS with thallium-201 for the assessment of left ventricular ejection fraction (LVEF) and regional wall motion by comparison with two-dimensional (2D) echocardiography (echo), which has not been done before. After injection of 111 MBq 201Tl at peak bicycle exercise (n=55) or pharmacological stress (n=17), GS was acquired 15 (post stress) and 120 min post injection (rest) on a double-head camera. An automatic algorithm (QGS) was used for processing. Echo (Acuson Sequoia C256) was performed immediately after rest GS. LVEFs assessed by GS and echo were correlated. The overall and segmental sensitivity and specificity of GS for the detection of regional wall motion abnormalities (WMAs) were calculated, echo serving as the gold standard. Perfusion abnormalities were scored. The success rate of the automatic algorithm was 100%, and visually assessed image quality was good to excellent in 88% of cases. Post-stress and rest LVEF as assessed by GS were highly correlated (r=0.91). Good correlations were obtained between post-stress LVEF (GS) and rest LVEF (echo) and between rest LVEF (GS) and rest LVEF (echo) (r=0.76 and 0.86 respectively). In patients with a reduced LVEF of less than 50% (n=23), these correlatio of less than 50% (n=23), these correlations were even better (r=0.84 and 0.89 respectively). Regional wall motion abnormalities (WMAs) were identified by GS with high sensitivity and specificity (88%-100% and 82%-98% respectively) and were directly related to the extent and severity of stress as well as of resting perfusion defects. It is concluded that GS with 201Tl is a feasible and reliable tool for the evaluation of patients with compromised left ventricular function in the context of coronary artery disease, and thus improves diagnosis and prognostic stratification. Regional WMAs were identified with high diagnostic accuracy and the method may prove helpful for the detection of myocardial viability. (orig.)

  12. Absorbed radiation to the nuclear medicine nurses from patients administered 201Tl and 99mTc- MIBI

    International Nuclear Information System (INIS)

    People who have administrated radiopharmaceuticals could be a source of radiation to their relatives, medical nurses, and people who have contact them. In this study, the dose rates at various distances of 5, 10,50 and 100cm from 70 patients, who were administered diagnostic amounts of 201Tl-Chloride and 99mTc-MIBI, was measured using an ionization chamber. For determination of external radiation dose to the nurses the radiations in three deferent interval times have measured. The maximum values of external dose rates of 201Tl and 99mTc- MIBI were 11.2?Sv/h ±2.3 and 43.1?Sv/h ±11.9 respectively at 5cm from the patients. Significant exposure from patients after injection of 99mTc-MIBI was limited on the day of administration. Departure doses rate of 201Tl fell gradually so by 3 days after administration was significant. Maximum and average absorbed dose of nuclear medicine staff for one 201Tl scan was 4.6 and 2.7?Sv/h, and for 99mTc-MIBI was 18.1 and 9.8?Sv/h in a working day. (author)

  13. Absorbed radiation to the nuclear medicine nurses from patients administered 201Tl and 99mTc- MIBI

    International Nuclear Information System (INIS)

    People who have administrated radiopharmaceuticals could be a source of radiation to their relatives, medical nurses, and people who have contact them. In this study, the dose rates at various distances of 5, 10,50 and 100 cm from 70 patients, who were administered diagnostic amounts of 201Tl -Chloride and 99mTc -MIBI, was measured using an ionization chamber. For determination of external radiation dose to the nurses the radiations in three deferent interval times have measured. The maximum values of external dose rates of 201Tl and 99mTc-MIBI were 11.2?Sv/h ±2.3 and 43.1?Sv/h ±11.9 respectively at 5 cm from the patients. Significant exposure from patients after injection of 99mTc -MIBI was limited on the day of administration. Departure doses rate of 201Tl fell gradually so by 3 days after administration was significant. Maximum and average absorbed dose of nuclear medicine staff for one 201Tl scan was 4.6 and 2.7?Sv/h, and for 99mTc-MIBI was 18.1 and 9.8?Sv/h in a working day. (author)

  14. Sympathetic reinnervation in cardiac transplants: 123I-MIBG and 201Tl/99mTc-MIBI scintigraphy

    International Nuclear Information System (INIS)

    The purpose was to evaluate cardiac sympathetic reinnervation and hemodynamic changes after orthotopic heart transplantation (TPL). We performed 24 serial or followup cardiac 123I-MIBG imaging and rest 201Tl/99mTc-MIBI dipyridamole stress gated myocardial perfusion SPECT (g-MPS) in 15 patients (M:F=10:5;mean ages=34.5±13.0 yr; idiopathic:rheumatic=14:1; one heart lung TPL)(10.80 ±11.88 (1-48) mo) after TPL 123I-MIBG imagings were performed in anterior position 15 minutes, 4 and 24 hours after i.v. injection of 148 MBq 123I MIBG. Image quantitation was based on the ratio of heart to mediastinal MIBG uptake (HMR) Compared to HMR on 15 min images (1.48 ± 0.28), neither four nor 24 hour delayed images (1.26 ± 0.23 vs. 1.06 ± 0.26: p<0.05, respectively, ANOVA) showed definite delayed localization of MIBG. 12 subjects with <13 (4.9 ±3.7) months after TPL had no visible 123I-MIBG uptake on early 15 min imaging however, 12 subjects with 13 to 48(28.6±12.8) months had visible cardiac 123I-MIBG uptake (HMR: 1.65±0.21 vs. 1.32±0.26; p=0.002). One-year followup 123I-MIBG scintigraphy in nine pts showed significantly increased HMR(1.40±0.31 to 1.61±0.16, p<0.05) but a plateau was reached at HMR value of 2.0, which was still lower than 3.0 in normal controls. Plasma NE was increased according to I-123 MIBG myocardial uptake. Annual G-MPS detected an allograft atherosclerosis in one pt and showed progressive normalization of tachycardia and significant deterioration of LVsignificant deterioration of LVEF and cardiac indices according to severity of rejection. To dipyridamole stress, transplant heats showed significant subnormal hemodynamic responses. Partial sympathetic late reinnervation can occur <1 year after TPL, and reached a plateau of two-third of normal value. G-MPS seems to be a useful screening test for the detection of allograft atherosclerosis and rejection

  15. I-123 MIGB and Tl-201 myocardial scintigraphies in patients with dilated cardiomyopathy

    International Nuclear Information System (INIS)

    123-metaiodobenzylguanidine (MIBG) and 201Tl myocardial scintigraphies were performed in 7 patients with dilated cardiomyopathy and the data obtained by both scintigraphies were compared with the ejection fraction (EF) determined by echocardiography. A myocardial SPECT was obtained at 15 minutes and at 4 hours after the i.v. injection of 111 MBq of 123I-MIBG and 201Tl-Cl. The SPECT data were visually analysed, and partly by quantitative methods. The perfusion defect of 123I-MIBG was larger than that of 201Tl in all 7 patients. The H/B (myocardium/background uptake ratio) of 201Tl and 123I-MIBG delayed imaging was significantly correlated with the EF (201Tl: r=0.949, 123I-MIBG: r=0.860, p123I-MIBG delayed imaging were also significantly correlated with the EF (r=-0.863, r201Tl were not. The WOR (washout rate) was not correlated with the EF in this study. These results suggest that 123I-MIBG myocardial scintigraphy provides useful information about the cardiac damage in patients with dilated cardiomyopathy. (author)

  16. Accuracy of preoperative pinhole subtraction single photon emission computed tomography for patients with primary and recurrent hyperparathyroidism in an endemic goiter area

    International Nuclear Information System (INIS)

    Bilateral parathyroid exploration is still the standard therapeutic procedure for primary and recurrent hyperparathyroidism (HPTH). Since a unilateral surgical strategy that reduces surgical complications should not increase the risk of missing enlarged parathyroid glands, reliable preoperative imaging is the first requirement for this approach. This study was conducted to assess the accuracy of preoperative 99mTcO4-201Tl pinhole subtraction single photon emission computed tomography (SPECT) compared with sonography. The study population consisted of 15 patients with primary (n=13) or recurrent (n=2) HPTH who underwent preoperative 99mTcO4-201Tl pinhole subtraction SPECT. Preoperative sonography was also done in 14 of these patients. 99mTcO4-201Tl pinhole subtraction SPECT was significantly more accurate than sonography. It had an overall accuracy of 80% in detection of enlarged parathyroid glands. The accuracy of localization increased to 92.3% in patients with solitary adenomas, and to 100% in those with solitary adenomas and no previous parathyroid exploration. The high accuracy of preoperative localization with 99mTcO4-201Tl pinhole subtraction SPECT in patients with primary and recurrent HPTH allows for an imaging-guided unilateral operative strategy in most patients, even those with concomitant nodular goiters. This may reduce the rant nodular goiters. This may reduce the risk of surgical complications and expand the use of minimally invasive techniques in parathyroid surgery. (author)

  17. Usefulness and limitations of ECG-gated myocardial single-photon emission computed tomography with 99mTc-methoxy-isobutyl-isonitrile (MIBI) in patients with prior myocardial infarction

    International Nuclear Information System (INIS)

    To evaluate the relationship between regional wall motion and 99mTc-methoxy-isobutyl-isonitrile (MIBI) uptake, ECG-gated single-photon emission computed tomography (SPECT) with 99mTc-MIBI was performed in 20 patients with prior myocardial infarction. The left ventricular images at end-diastole (ED) and end-systole (ES) were divided into 39 segments, respectively. Based on circumferential profile analysis, relative uptake (%EDc, %ESc), percent count increase (%?C), and normalized percent count increase (%?Cn) were analyzed in each segment and compared with regional wall motion indices assessed by echocardiography and left ventriculography. ECG-gated SPECT with 99mTc-MIBI provided high contrast tomograms of the left ventricular myocardium. %EDc and %ESc showed good correlations with regional wall motion indices. %?C and %?Cn, however, showed lower correlations compared with %EDc and %ESc. In conclusion, high-quality left ventricular images were obtained with 99mTc-MIBI ECG-gated SPECT, but quantitative analysis based on only percent count increase (%?C) have limitations for evaluation of regional wall motion. (author)

  18. Combined assessment of myocardial perfusion and function by ECG-gated myocardial perfusion single-photon emission computed tomography for the prediction of future cardiac events in patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    The mid-term prognostic significance of electrocardiogram (ECG)-gated single-photon emission computed tomography (SPECT) remains unclear in Japanese patients with type 2 diabetes mellitus (DM). In the present study rates of future cardiac events (nonfatal acute myocardial infarction (AMI), cardiac death (CD) and severe heart failure (HF) requiring hospitalization) were compared in patients with and without DM. 1,810 patients (563 DM and 1,247 non-DM) we followed for a mean of 26.3±15.5 months. Summed stress score (SSS), summed difference score (SDS), poststress ejection fraction (EF) and resting end-diastolic volume (EDV) were calculated. In total, 20 cases of AMI (9 in DM (1.59%) and 11 in non-DM (0.88%)), 20 of CD (7 in DM patients (1.24%) and 13 in non-DM (1.04%)) and 54 of severe HF (31 in DM (5.5%) and 23 in non-DM (1.84%)) occurred. Univariate Cox analysis showed that, in DM patients, predictors of total cardiac events were poststress EF (Wald 60.4; P1c value (Wald 4.30; P<0.05). Multivariate Cox analysis showed that poststress EF (Wald 9.85; P<0.01) and SDS (Wald 6.19; P<0.01) were independent predictors of total cardiac events. Combined assessment of perfusion and function by ECG-gated SPECT may predict future cardiac events in type 2 DM patients. (author)

  19. Improved detection of fill-in using sublingual nitroglycerin in technetium-99m tetrofosmin exercise/rest single photon emission computed tomography one day protocol for old myocardial infarction

    International Nuclear Information System (INIS)

    Twenty-one patients with old myocardial infarction underwent repeated 99mTc-tetrofosmin (99mTc) exercise/rest same day protocols with and without the administration of sublingual nitroglycerin (NTG) 5 min before the second injection of 99mTc for rest SPECT. Twelve of these patients also underwent ordinary exercise/redistribution 201Tl SPECT. The control study protocol images showed decreased uptake of 99mTc on exercise in 157 of 420 segments and the presence of fill-in at rest in 58 segments. Images obtained with administration of NTG showed decreased uptake of 99mTc on exercise in 163 of 420 segments and fill-in in 74 segments at rest. The frequency of fill-in was greater in the NTG protocol than in the control protocol. The segments were scored as different grades according to 99mTc uptake between 2 protocols. Fill-in was only present or more remarkable in 31 segments in the NTG protocol than in the control protocol. Fill-in was only present or more remarkable in 10 segments in the control protocol than in the NTG protocol. In the NTG protocol, the mean defect score of the exercise images, calculated from the bull's eye image automatically, was higher than that of the rest images. The mean severity score of the exercise images, also calculated from the bull's eye image automatically, was likewise higher than that of the rest images, whereas the mean severity score of the stress images and r severity score of the stress images and rest images in the control protocol was not significantly different. Moreover, the mean defect score and severity score of the rest images from the NTG protocol were significantly lower than those obtained from the control protocol. Sublingual NTG administration before the injection of 99mTc-tetrofosmin at the rest study in the one day exercise/rest studies enhanced fill-in, so may enhance the detection of viable myocardium, allowing more informed decisions regarding cardiac revascularization in patients with chronic coronary artery disease. (K.H.)

  20. Serial changes in myocardial perfusion and function after successful percutaneous transluminal coronary angioplasty, examined by stress thallium-201 myocardial scintigraphic and stress radionuclide ventriculographic studies

    International Nuclear Information System (INIS)

    In order to study the early and late effects of percutaneous transluminal coronary angioplasty (PTCA), 201Tl myocardial perfusion scintigraphy and exercise 99mTc ventriculography were performed in 25 patients who successfully received PTCA. Before PTCA, reduced myocardial perfusion on stress 201Tl image was observed in all 25 patients, while abnormal regional wall motion during exercise was seen in 22 cases. On stress 201Tl images, reduced myocardial perfusion was demonstrated in 11 cases at 3-7 days after PTCA, but in none at 3 months after the procedure. On the other hand, abnormal exercise regional wall motion was not observed in any case after successful PTCA even in the early phase. When the patients were divided into two groups according to the presence or absence of perfusion abnormalities on stress 201Tl images in the early post-PTCA phase, no difference was seen in clinical and coronary angiographic findings, exercise tolerance, 201Tl uptake score, wall motion score or left ventricular ejection fraction before the procedure. Thus, abnormal myocardial perfusion without impairment of regional left ventricular wall motion is frequently seen in the early post-PTCA phase. But this finding does not necessarily indicate associated myocardial ischemia. (author)

  1. Pathophysiology of technetium-99m stannous pyrophosphate and thallium-201 scintigraphy of acute anterior myocardial infarcts in dogs

    International Nuclear Information System (INIS)

    In 17 dogs with acute myocardial infarcts produced by ligation of the proximal left anterior descending coronary artery, a comparative study was made of myocardial scintigrams obtained with technetium-99m stannous pyrophosphate (/sup 99m/Tc-PYP) and thallium-201 (201Tl), tissue levels of /sup 99m/Tc-PYP and 201Tl uptake, histopathologic alterations, and regional myocardial perfusion measured with radioactive microspheres. Nine of the 10 hearts examined histologically had transmural infarcts with outer peripheral, inner peripheral, and central zones characterized by distinctive histopathologic features. A progressive reduction in myocardial blood flow was demonstrated between normal myocardium and the centers of the infarcts, and correlated well with progressive reduction in 201Tl uptake in the same regions. Marked /sup 99m/Tc-PYP concentration occurred in areas with partial to homogeneous myocardial necrosis and residual perfusion located in the outer peripheral regions of the infarcts. The latter areas also were characterized by the presence of muscle cell calcification. The patterns of distribution of /sup 99m/Tc-PYP and 201Tl explained the filling defects on 201Tl myocardial scintigrams and the doughnut patterns on /sup 99m/Tc-PYP myocardial scintigrams in dogs with transmural infarcts. One dog with a subendocardial infarct had a small homogeneous area of activity on the /sup 99m/Tc-PYP myocardial scintigram; ae /sup 99m/Tc-PYP myocardial scintigram; and showed marked uptake of /sup 99m/Tc-PYP in subendocardial areas of extensive necrosis and calcification still receiving some coronary perfusion. Thus, the data indicate that the status of regional myocardial perfusion is a key determinant for the occurrence of distinctive patterns of myocardial necrosis and for the scintigraphic detection of acute myocardial infarcts with /sup 99m/Tc-PYP and 201Tl

  2. Myocardial perfusion in patients with left bundle branch block and without coronary artery disease

    International Nuclear Information System (INIS)

    For the evaluation of myocardial perfusion in patients with left bundle branch block (LBBB), we performed exercise stress (Ex)-redistribution (RD) myocardial tomography with thallium-201 (201Tl) in 23 patients with LBBB and without coronary artery disease (CAD). Myocardial images in patients with LBBB were compared with those of 9 patients with CAD who showed Ex induced transient septal defect. Bull'-eye maps (201Tl distribution maps at Ex and RD and 201Tl washout rate [WOR] map) were made from myocardial tomograms. In 23 patients with LBBB, 15 patients (65%) developed myocardial perfusion abnormality. In 10 (67%) of these 15 patients, transient perfusion defect appeared in the entire septum (diffuse type). On the other hand in 5 patients (33%), localized fixed perfusion defect developed at the boundary between septum and anterior wall (focal type). In focal type, every patient had other disease such as hypertension, aortic stenosis or sick sinus syndrome. While in patients with diffuse type, other diseases were observed in 30% (p201Tl WOR and 201Tl uptake ratio of septum to lateral wall indicated that exercise induced septal defect was slighter in diffuse type than CAD. These points might be useful to differentiate whether CAD participates in the septal defect or not in patients with LBBB. (author)

  3. 201-thallium myocardial imaging in evaluation of antianginal drugs effect on myocardial perfusion in ischemic patients

    International Nuclear Information System (INIS)

    The study comprised 62 ischemic patients, 38 of them suffered previous myocardial infarction. All patients had expressed angina pectoris and they were examined with 201-Tl myocardial scintigraphy both at rest and during maximum bicycle exercise test before as well as after acute administration of one of the three antianginal drugs: Nitroglycerin, Nitrong or Corvaton. 201-Tl myocardial perfusion imaging at rest revealed local perfusion defects in 62 patients. Transient myocardial ischemia was revealed in 49 of 54 ischemic patients examined during exercise. 201-Tl myocardial scintigrams showed no changes in 9 patients. After antianginal drug administration decrease of perfusion defect was marked only in 17 of 31 patients examined at rest. In the majority of cases beneficial effect of antianginal drugs manifested in the decrease or prevention of transient myocardial ischemia during exercise, was observed. Nitroglycerin had most expressed beneficial effect on myocardial perfusion. This effect was most pronounced in limitation of myocardial ischemic zone at rest and in prevention of transient ischemia appearance during exercise equal to the one that originally induced myocardial ischemia. Nitrong (Nitroglycerin of the prolonged action) and Corvaton (peripheral vasodilator) also had beneficial effect on myocardial perfusion, however, less expressed at rest if compared to Nitroglycerin. Effect of Nitrong and Corvaton was most pronounced in prevention and limitation of myocarced in prevention and limitation of myocardial transient ischemic zone during exercise

  4. Myocardial ischemia with negative stress electrocardiography

    International Nuclear Information System (INIS)

    Patients with negative stress electrocardiography (ECG) (no ST segment depression) were re-evaluated by means of stress RI studies including 201Tl single photon emission computed tomography (SPECT) and 99mTc-RBCs radionuclide ventriculography (RNV). Four hundred seven patients, including 303 with old myocardial infarction (OMI; SPECT: 188, RNV: 115) and 104 with effort angina (EA; SPECT: 58, RNV: 46), all of whom underwent left ventriculography and coronary arteriography, were re-evaluated by symptom-limited graded bicycle ergometer exercise RI testing. The results were as follows: 1. Among those with negative stress ECG (53 % of OMI and 31 % of EA), 54 % and 73 % of OMI and EA, respectively, had positive SPECT. 2. Among those with negative stress ECG (56 % of OMI and 39 % of EA), 70 % and 39 % of OMI and EA, respectively, had positive ?EF (poor increase in ejection fraction: ?EF < 5 %) and, 41 % and 28 % of OMI and EA had deteriorated regional wall motion. 3. Those with OMI and negative ECG showed no correlations with the numbers of diseased vessels, infarcted sites, or ischemic areas. In conclusion, RI testing appears to be a significantly more sensitive means of detecting stress-induced ischemia, compared to stress ECG. (author)

  5. Leg {sup 201}Tl-SPECT in chronic exertional compartment syndrome; Tomoscintigraphie des jambes au thallium 201 dans le diagnostic du syndrome de loge chronique

    Energy Technology Data Exchange (ETDEWEB)

    Elkadri, N.; Slim, I.; Blondet, C.; Choquet, Ph.; Constantinesco, A. [Hopital Hautepierre, Service de Biophysique et Medecine Nucleaire, 67 - Strasbourg (France); Lecocq, J. [Hopital Hautepierre, Service de Medecine Physique et Readaptation, 67 - Strasbourg (France)

    2004-06-01

    Leg {sup 201}Tl-SPECT in chronic exertional compartment syndrome Background: The chronic exertional compartment syndrome is one of the most frequent origins regarding leg pain due to sport training. The diagnosis can be established by invasive compartment pressure measurement. The aim of this study is to evaluate the role that could have {sup 201}Tl-SPECT for patients with suspicion of compartment syndrome. Patients and methods: 51 leg {sup 201}Tl-SPECT exams were performed (exercise - and rest without reinjection) in 49 patients; 28 had compartment syndrome confirmed by pressure measurement. About 100 MBq of {sup 201}Tl were injected during exercise, when pain appeared or at least after 25 minutes exercise. We studied mean percentages of level uptake for each compartment, referred to the maximal uptake of both legs. Results: 47 compartments were concerned by compartment syndrome and 361 compartments were not. Scintigraphic patterns in compartments are reversible ischaemia (45%), uptake stability (36%) or reverse redistribution (19%); these patterns are not linked to compartment syndrome. However, there is a significant difference of rest {sup 201}Tl level uptake between compartments with and without compartment syndrome and a significant correlation between muscular pressure measurement and rest level uptake. Conclusion: {sup 201}Tl-SPECT shows that only ischaemia does not explain compartment syndrome. Moreover, it allows to predict pressure variation during exercise but it does not offer any interest in order to select patients for muscular invasive pressure measurement. (author)

  6. Utilidad de la tomografía computarizada de emisión de fotón único sincronizada con el electrocardiograma para la detección de isquemia miocárdica silente en diabéticos tipo 2 Gated single photon emission computer tomography for the detection of silent myocardial ischemia

    Directory of Open Access Journals (Sweden)

    Yamilé Peña Q

    2009-08-01

    Full Text Available Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT for the screening of silent myocardial ischemia in type 2 diabetic patients. Material and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. AH subjects were also subjected to a coronary angiography whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specifity accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873. Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia.

  7. Utilidad de la tomografía computarizada de emisión de fotón único sincronizada con el electrocardiograma para la detección de isquemia miocárdica silente en diabéticos tipo 2 / Gated single photon emission computer tomography for the detection of silent myocardial ischemia

    Scientific Electronic Library Online (English)

    Yamilé, Peña Q; Marco Antonio, Coca P; Juan Felipe, Batista C; José, Fernández-Britto R; Rodobaldo, Quesada P; Andria, Peña C.

    1023-10-01

    Full Text Available [...] Abstract in english Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients. Materi [...] al and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. AH subjects were also subjected to a coronary angiography whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specifity accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873). Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia.

  8. Single-photon imaging

    CERN Document Server

    Seitz, Peter

    2011-01-01

    The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncoooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist´s view from different domains to the forthcoming “single-photon imaging” revolution. The various aspects of single-photon imaging are treated by internati...

  9. Diagnostic accuracy of 201Tl SPECT·MRI in brain diseases and inter-reader variance of diagnostic performance

    International Nuclear Information System (INIS)

    Fifteen-four studies of 201Tl brain tumor SPECT were independently interpreted by 9 nuclear medicine physicians with and without reference magnetic resonance images in 2 separate sessions to define an effect of referring images, and inter-observer variations. The physicians were requested to detect foci of abnormal deposits, and to discriminate whether they were malignant or not according to 5-grade scaling of subjective diagnostic confidence. Receiver-operating characteristics (ROC) analysis was performed. Mean sensitivity for presence of lesions (SFP), and sensitivity and specificity for malignancy of 201Tl SPECT were 84, and 53 and 55%, which were changed to 94 and 74 and 55% after referring to the MR images. The SFP was significantly improved (p201Tl brain tumor SPECT has moderate sensitivity and specificity for malignancy, which is not improved by addition of anatomical reference images, that additional MR images reduce inter-observer variation of confidence on lesion presence, and that SPECT localization of lesions has great inter-observer variations.sions has great inter-observer variations. (author)

  10. Differential diagnosis of benign and malign intracranial tumors by SPECT with 201Tl by means of early and late acquisition

    International Nuclear Information System (INIS)

    Having in view the difficulty of establishing a discriminant threshold to differentiate the benign or malign tumoral intracranial pathology on the basis of a single early acquisition, we have modified our protocol by performing a SPECT at 15 minutes and 4 h after IV injections of 185 MBq of 201Tl. Thirty four tumors (29 malign and 5 benign) were studied on a double head Elscint Helix HR camera with fan collimators. The SPECT were reconstructed by retro-projection with a Metz 3.13 filter. The activity ratios were calculated at two times of explorations (average counts per pixel in the pathological zone/average counts per pixel of the mirrored zone of the healthy hetero-lateral side). A retention rate (RR) of 201Tl for tumor was also calculated (late ratio/early ratio). In cases when isolated early and late ratios do not allow to differentiate among the benign and malign tumors, the RR appear to be very discriminant in differentiating benign and malign tumors. The benign tumors widen 201Tl more rapidly. From the data obtained we have calculated the best threshold allowing to differentiate the RR of the two types of tumors. In our experiment this amounts up to 0.60, what permits diagnosing 100% of the malign tumors (RR>0.6) and 80% of benign tumors (RR<0.6), i.e. a precision in diagnosis of 97%

  11. Dual myocardial single photon emission computed tomography (SPECT) using thallium-201 and I-123-{beta}-methyl-i-pentadecanoic acid in patients with Duchenne's progressive muscular dystrophy

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    Shimoyama, Katsuya [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    1999-10-01

    Dual single photon emission computed tomography (SPECT) was performed in 31 patients with Duchenne's progressive muscular dystrophy (DMD) using {sup 123}I-{beta}-methyl pentadecanoic acid (BMIPP) for myocardial fatty acid metabolism and {sup 201}thallium (Tl)-chloride for myocardial perfusion. The left ventricle was divided into 9 segments, and accumulation of the radiotracers was assessed visually for each segment to calculate defect score for each tracer. There was some degree of decrease in myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP: 67%, Tl: 63%), followed by the posterior wall, lateral wall, and anterior wall. On the other hand, reduced accumulation was less common at the septum. BMIPP showed a higher accumulation than Tl in all segments but the septum. When BMIPP defect score was larger than Tl defect score, BMIPP defect score tended to increase during 4 years follow-up (p<0.042). However, when Tl defect score was larger than BMIPP defect score, an increase in Tl defect score was slight. A significant negative correlation was found between the sum of the BMIPP and Tl defect scores and the left ventricular ejection fraction (LVEF) (r=0.66, p<0.0001). According to the histo-pathological study of two autopsied hearts, severe myocardial fibrosis was seen in segments with fixed perfusion defect. In addition, the mismatched segments of BMIPP defect score > Tl defect score revealed a slight fibrosis or normal myocardium. It can be concluded that the dual SPECT myocardial scintigraphy using BMIPP and Tl provides accurate information about disease progression of the heart in patients with DMD by detecting abnormalities of the myocardial metabolism of each substance, thereby enabling the assessment of left ventricular function. (author)

  12. A procedure for the production of injection substance containing 201Tl thallium chloride

    International Nuclear Information System (INIS)

    Injection substance containing 201TlCl can be prepared by the following procedure. To a solution of irradiated thallium target in dilute H2SO4 is added a solution of KBrO3 in an amount at least sufficient for transforming all the thallium to the trivalent state. A solution of NaBr or KBr is then added and the target amount of Tl is separated from 201Pb by repeated extraction into diisopropyl ether. In 24 to 40 hr, KBrO3 is again added in an amount at least such that thallium is transformed to the trivalent state, and the latter is separated from lead by a single extraction into diisopropyl ether. The organic phase is washed with a solution of NaBr or KBr in dilute H2SO4 and reextracted into injection-grade water containing dissolved SO2. The reextract is evaporated, dissolved in buffer-containing isotonic solution and autoclaved. The chemical yield is 97 to 98%, the first step of the procedure takes 30 to 35 min, and the technological yield of the process is 90%. The injection is high-quality. (P.A.)

  13. Development of [{sup 201}Tl](III)-DTPA-human polyclonal antibody complex for inflammation detection

    Energy Technology Data Exchange (ETDEWEB)

    Jalilian, A.R.; Kamali-Dehghan, M.; Kamrani, Y.Y. [Nuclear Research Center for Agriculture and Medicine, Karaj (Iran). Cyclotron and Nuclear Medicine Dept.; Khorrami, A.; Tavakoli, M.B. [Medical Sciences Univ. of Isfahan (Iran). Medical Physics and Engineering Dept.

    2007-07-01

    Thallium-201 (T{sub 1/2}=3.04 d) in Tl{sup +} form was converted to Tl{sup 3+} cation in presence of O{sub 3} in 6 M HCl controlled by RTLC/gel electrophoresis methods and used in the labeling of human polyclonal antibody (HIgG) after conjugation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of 1 mL of a HIgG pharmaceutical solution (5 mg/ml, in phosphate buffer, pH=7) to a glass tube pre-coated with DTPA-dianhydride (0.01 mg) at 25 C with continuous mild stirring for 30 min. The final isotonic [{sup 201}Tl](III)-DTPA-HIgG complex was checked by radio-TLC using several solvent systems to ensure the formation of only one species followed by filtration through a 0.22 {mu} filter (specific activity= 33.7 TBq/mM, radiochemical purity >95%). Preliminary bio-distribution studies in normal and inflammation-bearing rats were performed. The target/skin and target/blood ratios were 4 and 6 after 28 h respectively, showing the selectivity of the radiopharmaceutical for the inflammatory lesions. (orig.)

  14. Quantitative 201Tl scintigraphy of the lower limbs in peripheral artery disease

    International Nuclear Information System (INIS)

    201Tl scintigraphy is useful in evaluating the hemodynamic consequences of arterial stenoses in arterial occlusive disease. The aim of the present study was to determine normal values for absolute Tl uptake in the lower leg, for the quotient between left and right lower leg uptake as well as for the redistribution pattern after bicycle exercise. We examined as reference 49 patients without clinical evidence of peripheral or coronary artery disease: absolute Tl uptake in the lower leg in anterior scintigraphy (acquisition time: 120 sec) was 5.02±1.70 counts/pixel (left) 5.21±1,53 counts/pixel (right), the quotient between right and left lower leg was 0.85±0.09 and the redistribution pattern (quotient of the mean activity exercise/rest) 0.82±0.17 (left) and 0.83±0.15 (right). The arithmetic mean minus 2 standard deviations was regarded as the lower limit of normal. In 8 patients with mechanical compression of the left femoral artery before injection at least two scintigraphic parameters were abnormal, in 7 patients with angiographically proven peripheral artery disease at least one scintigraphic parameter was below normal. Quantification of Tl redistribution offers diagnostic advantages in bilateral peripheral artery disease. (orig.)

  15. Development of [201Tl](III)-DTPA-human polyclonal antibody complex for inflammation detection

    International Nuclear Information System (INIS)

    Thallium-201 (T1/2=3.04 d) in Tl+ form was converted to Tl3+ cation in presence of O3 in 6 M HCl controlled by RTLC/gel electrophoresis methods and used in the labeling of human polyclonal antibody (HIgG) after conjugation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of 1 mL of a HIgG pharmaceutical solution (5 mg/ml, in phosphate buffer, pH=7) to a glass tube pre-coated with DTPA-dianhydride (0.01 mg) at 25 C with continuous mild stirring for 30 min. The final isotonic [201Tl](III)-DTPA-HIgG complex was checked by radio-TLC using several solvent systems to ensure the formation of only one species followed by filtration through a 0.22 ? filter (specific activity= 33.7 TBq/mM, radiochemical purity >95%). Preliminary bio-distribution studies in normal and inflammation-bearing rats were performed. The target/skin and target/blood ratios were 4 and 6 after 28 h respectively, showing the selectivity of the radiopharmaceutical for the inflammatory lesions. (orig.)

  16. Adsorption kinetics of 201Tl and migration of 99mTc in natural soils

    International Nuclear Information System (INIS)

    The safety is very important in facilities where radioactive wastes are stored. One of the necessary characteristics of the site where these wastes will be disposed is the soil permeability, since a waterproof terrain avoids the diffusion and radionuclide transport in the leakages case. The objective of this work is to study the adsorption kinetics of 201Tl and the migration of 99mTc in natural soil samples. The adsorption kinetics was determined starting from the obtaining of the retention coefficient of the thallium (static method) at different contact times. The technetium diffusion was studied by means of the dynamic method with different soil particles sizes. The results showed that the thallium is totally adsorbed starting from 20 h of contact among this and the mean. On the other hand, the technetium is very mobile in the soil, since it was possible to extract the majority of the tracer with little solvent. Also, it was found that for each soil gram the double water will be needed to leach the technetium almost in its entirety. Moreover, influence exists of the particle size in the migration velocity from the radiotracer to the most mobile being in major sizes than 2 mm that in minor size. (Author)

  17. Detecting and localizing peripheral arterial disease: assessment of 201Tl scintigraphy

    International Nuclear Information System (INIS)

    Detection and localization of peripheral arterial disease was evaluated by intravenous injection of 201Tl at peak exercise in 22 subjects. Images of the gluteals (G), thighs (T), knees (K), and calves (C) were obtained at exercise and after a 3 hr delay, and stored in a computer, interextremity (T/T and C/C) and intraextremity (G/T, T/C, T/K) counts ratios were calculated. Normal values were defined in 11 control subjects and compared with those obtained in 11 patients with angiographically proven peripheral arterial disease. Bilateral disease was detected scintigraphically in all patients. T/T and G/T ratios correctly predicted proximal disease in nine of 12 limbs, while C/C, T/C, T/K ratios correctly predicted distal disease in 21 of 21 involved limbs. Delay images 3 hr after stress generally reverted towards the norm. Objective systematic evaluation of limb isotope uptake permits accurate detection and localization of peripheral arterial disease. Method accuracy compares favorably with physical signs and with other noninvasive methods of detection of peripheral vascular disease. Scintigraphy presents advantages which indicate great clinical potential

  18. Clinical significance of stress-induced ST segment changes in patients with previous myocardial infarction

    International Nuclear Information System (INIS)

    To explain the clinical significance of stress(st)-induced ST-segment (ST) changes postinfarction, 93 patients with previous myocardial infarction (MI) were performed st-201Tl myocardial single photon emission computed tomography (SPECT) and compared ST changes with SPECT, coronary arteriographic and left ventriculographic findings. 30 out of 93 cases (32%) had ST depression, 20 (21.5%) had ST elevation, 9 (10%) had both ST depression and elevation and remaining 34 (36.5 %) had no significant ST changes. In single vessel disease, ST depression were noted in 29% (12/42), while in multivessel disease, 53% (27/51). 35 out of 39 cases (90%) with ST depression had transient perfusion defect but no apparent relation was noted between location of ST depression on ECG and region of transient perfusion defect in SPECT. All of 28 cases with ST elevation were noted in anterior MI cases, and 26 out of these showed severe LV wall motion abnormality in contrast left ventriculography and broad anterior permanent defect in SPECT. Only 15 cases (54%) showed slight redistribution. Thus, we conclude that in patients with previous MI, st-induced ST depression seems to reflect myocardial ischemia and ST elevation possibly related abnormal LV wall motion. (author)

  19. Clinical study on myocardial imaging with ?-methyl-p-(123I)-iodophenyl-pentadecanoic acid in patients with mitochondrial myopathy

    International Nuclear Information System (INIS)

    Myocardial imaging with ?-methyl-p-(123I)-iodophenyl-pentadecanoic acid (123I-BMIPP), a new radiopharmaceutical designed to evaluate myocardial fatty acid metabolism, was performed in 7 patients with mitochondrial myopathy to detect their myocardial damages in comparison with 201Tl myocardial imaging. These patients were divided into 4 chronic progressive external ophthalmoplegia (CPEO) cases, 2 mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) cases and 1 myoclonus epilepsy with ragged-red fibers (MERRF). In visual assessment, we observed more myocardial segments with decreased uptake of 123I-BMIPP compared to 201Tl in MELAS cases than in CPEO cases. The mean myocardial uptake of 123I-BMIPP was higher than that of 201Tl in CPEO cases. On the other hand, in MELAS and MERRF cases, the mean myocardial uptake of 123I-BMIPP was lower than that of 201Tl. Abnormal findings suggesting myocardial damages were observed in echocardiogram and/or in electrocardiogram in MELAS and MERRF cases, while no such abnormal findings were observed in CPEO cases. Along with the previously reported experimental result that the impairment of rat myocardial mitochondria decreased myocardial uptake of 123I-BMIPP, these results suggest that 123I-BMIPP may be useful to detect myocardial damages in patients with mitochondrial myopathy. (a patients with mitochondrial myopathy. (author)

  20. Value of 201Tl imaging in predicting therapeutic 131I uptake in patients with thyroglobulin-positive but 131I scan-negative differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Background: Serum thyroglobulin assay and 131Iodine (1311) whole body scan are considered complementary in detecting malignant thyroid tissue or metastases. A large number of patients, however, are encountered presenting with scan-negative, thyroglobulin-positive differentiated thyroid carcinoma posing a dilemma in therapeutic management. One of the first alternative scanning agents to be employed is 201Thallium (201Tl). Recent studies have demonstrated its usefulness in identifying lesions that are not visualized with traditional 131I whole body scan. It is not clear, however, whether 201Tl scan helps in the decision-making for subsequent 131I therapy. This study was conducted to determine if 201Tl scan can predict therapeutic 131I uptake and to define the clinical role of 201Tl scanning in these patients. Methods and results: A total of 12 patients (20-63 y/o), 5 males and 7 females, underwent surgery for differentiated thyroid cancer and all had serum thyroglobulin values above 10 ng/ml and normal TPO autoantibodies. Pre-therapy 131I scan using 111 MBq (3mCi) of 131I were obtained. As required for inclusion, all patients had negative pre-therapy scan and negative TPO autoantibody results and underwent 20lTl scanning within 3 weeks. All patients were given 131I therapy (3.7-5.5 GBq or 100-150 mCi) between one to two months after 201Tl scanning. Within a week after therapy, all patients underwent whole body 1311 scanning. 201Tl imaging demonstrated thyroid remnants iTl imaging demonstrated thyroid remnants in 9 out of 12 patients having positive 201Tl scan but negative pre-therapy 1311 scan. However, only 2 of the positive 201Tl scans showed 131I uptake post-therapy (positive predictive value of 20%). None of the subjects presented with a negative 201Tl scan and a positive post-therapy 131I scan. Conclusion: Our study suggests that evidence of remnants or metastases on 201Tl scanning may be an inappropriate basis for the decision to proceed with 131I therapy. The role of 20lTl imaging in this subset of patients may be limited to localization of metastases for surgical excision or localized radiation therapy. (authors)

  1. Single photon quantum cryptography

    CERN Document Server

    Beveratos, A; Gacoin, T; Villing, A; Poizat, J P; Grangier, P; Beveratos, Alexios; Brouri, Rosa; Gacoin, Thierry; Villing, Andre; Poizat, Jean-Philippe; Grangier, Philippe

    2002-01-01

    We report the full implementation of a quantum cryptography protocol using a stream of single photon pulses generated by a stable and efficient source operating at room temperature. The single photon pulses are emitted on demand by a single nitrogen-vacancy (NV) color center in a diamond nanocrystal. The quantum bit error rate is less that 4.6% and the secure bit rate is 9500 bits/s. The overall performances of our system reaches a domain where single photons have a measurable advantage over an equivalent system based on attenuated light pulses.

  2. Single photon quantum cryptography

    OpenAIRE

    Beveratos, Alexios; Brouri, Rosa; Gacoin, Thierry; Villing, Andre; Poizat, Jean-Philippe; Grangier, Philippe

    2002-01-01

    We report the full implementation of a quantum cryptography protocol using a stream of single photon pulses generated by a stable and efficient source operating at room temperature. The single photon pulses are emitted on demand by a single nitrogen-vacancy (NV) color center in a diamond nanocrystal. The quantum bit error rate is less that 4.6% and the secure bit rate is 9500 bits/s. The overall performances of our system reaches a domain where single photons have a measurab...

  3. Analysis of heavy metals in [201Tl]TlCl injection using polarography

    International Nuclear Information System (INIS)

    Thallous-201 chloride produced at Korea Cancer Center Hospital(KCCH) is used in detecting cardiovascular disease and cancer. Thallium impurity can cause emesis, catharsis and nausea, so the presence of thallium and other metal impurities should be determined. According to USP and KP, their amounts must be less than 2 ppm in thallium and 5 ppm in total. In this study, the detection method of trace amounts of metal impurities in [201Tl]TlC1 injection with polarography was optimized without environmental contamination. For the detection of metal impurities, Osteryoung Square Wave Stripping Voltammetry method was used in Bio-Analytical System (BAS) 50W polarograph. The voltammetry was composed of Dropping Mercury Electrode (DME) as a working electrode, Ag/AgCl as a reference electrode and Pt wire as a counter electrode. Square wave stripping method, which makes use of formation and deformation of amalgam, was adopted to determine the metal impurities, and pH 7 phosphate buffer was used as supporting electrolyte. T1, Cu and Pb in thallous-201 chloride solution were detected by scanning from 300mV to -800mV. Calibration curves were made by using TINO3, CuSO4 and Pb(NO3)2 as standard solutions. T1 was confirmed at -450mV peak potential and Cu at -50mV. Less than 2 ppm of T1 and Cu was detected and Pb was not detected in KCCH-produced thallous-201 chloride injection. Detection limit of thallium and copper is approximatelyit of thallium and copper is approximately 50 ppb with this method. As a result of this experiment, thallium and other metal impurities in thallous-201 chloride injection, produced at Korea Cancer Center Hospital, are in the regulation of USP and KP. Polarograph could be applied for the determination of metal impurities in the quality control of radiopharmaceuticals conveniently without environmental contamination.=20

  4. Reevaluation of 201Tl-SPECT for patients with solitary pulmonary nodule. Comparison study with biopsy method and tumor marker measurement

    International Nuclear Information System (INIS)

    We compared the differential diagnostic capabilities of 201Tl-SPECT and biopsy methods and serum tumor marker in 125 patients with solitary pulmonary lesions composed of 87 lung cancer and 38 benign lesions. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 201Tl-SPECT were 76%, 95%, 97%, 63%, and 82%, respectively. These parameters are similar in biopsy methods. Although sensitivity improved to be 85% by the combination with tumor marker methods, both specificity and accuracy deteriorated to be 55% and 76%. Using combination method with 201Tl-SPECT and biopsy, sensitivity, NPV and accuracy improved to be 84%, 70% and 85%. Based on its high PPV value, 201Tl-SPECT could be useful when biopsy method could not prove lung cancer or in case whose biopsy is considered to be invasive. Because of the lower NPV value owing to false negative cases in some adenocarcinoma, negative 201Tl-SPECT case should be followed up carefully. (author)

  5. Single-photon imaging

    International Nuclear Information System (INIS)

    The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist's view from different domains to the forthcoming ''single-photon imaging'' revolution. The various aspects of single-photon imaging are treated by internationally renowned, leading scientists and technologists who have all pioneered their respective fields. (orig.)

  6. Single photon emission computerized tomography

    International Nuclear Information System (INIS)

    In this thesis two single-photon emission tomographic techniques are presented: (a) longitudinal tomography with a rotating slanting-hole collimator, and (b) transversal tomography with a rotating gamma camera. These methods overcome the disadvantages of conventional scintigraphy. Both detection systems and the image construction methods are explained and comparisons with conventional scintigraphy are drawn. One chapter is dedicated to the determination of system parameters like spatial resolution, contrast, detector uniformity, and size of the object, by phantom studies. In separate chapters the results are presented of detection of tumors and metastases in the liver and the liver hilus; skeletal diseases; various pathological aberrations of the brain; and myocardial perfusion. The possible use of these two ect's for other organs and body areas is discussed in the last chapter. (Auth.)

  7. Prognostic value of Tl-201 stress scintigraphy in patients with inferior myocardial infarction

    International Nuclear Information System (INIS)

    The results demonstrate that 201Tl imaging is superior to stress ECG in predicting additional reversible ischemia in patients with previous inferior myocardial infarction. The predictive accuracy for involvement of the LAD was significantly higher (71% vs 44%) than stress ECG. The predictive accuracy for involvement of the circumflex artery was very low (25%). An additional advantage is the high specificity of 201Tl imaging. In some patients abnormal ST-depressions in the anterior chest leads of the stress ECG can reflect collateral circulation to the occluded right coronary artery and not LAD diseases. These results emphasize the prognostic implications of Tl imaging in patients with previous inferior myocardial infarction

  8. Role of technetium 99m methoxyisobutylisonitrile single photon emission tomography in the evaluation of thrombolysis in acute myocardial infarction before and after admission to hospital

    International Nuclear Information System (INIS)

    To investigate initial perfusion status in acute myocardial infarction, methoxyisobutylisonitrile (MIBI) was administered by the rescue physicians. Some 39 patients received the radiopharmaceutical at home or upon arrival at the hospital. Diagnosis was confirmed in 30 patients, and 19 emergency thrombolyses were performed. Initial single pluton emission tomography (SPET) analysis was constantly abnormal in confirmed myocardial infarction sometimes before direct electrocardiographic signs. MIBI-SPET was normal in non-coronary syndromes. MIBI uptake improved after thrombolysis (P<0.001) but also after heparin therapy (P<0.05). SPET improvement demonstrated myocardial salvage earlier than wall motion studies. MIBI adminstration at the patient's home allowed very early perfusion imaging when thrombolysis was performed at home. MIBI-SPET has the potential use of comparing thrombolytic agents or at home versus in hospital thrombolysis. (orig.)

  9. Diagnostic value of early and delayed 201Tl thyroid scintigraphy in the evaluation of cold nodules for malignancy

    International Nuclear Information System (INIS)

    We performed 201Tl thyroid scintigraphy using an early and delayed scanning technique in 34 patients exhibiting cold nodules on sup(99m)Tc scans. Of the 29 benign nodules, 27 were correctly diagnosed as being negative, i.e. 93% specificity. However, two of five malignant nodules failed to concentrate activity on both the early and delayed scans. The low sensitivity (60%) of this method for detecting carcinomas limits its clinical value in the routine diagnostic work-up of patients with suspected thyroid cancer. Our findings are in contrast to previous more optimistic reports. (orig.)

  10. Radionuclide imaging in myocardial sarcoidosis. Demonstration of myocardial uptake of /sup 99m/Tc pyrophosphate and gallium

    International Nuclear Information System (INIS)

    A patient had severe congestive cardiomyopathy secondary to myocardial sarcoidosis. The clinical diagnosis was confirmed by radionuclide ventriculography, 201Tl, 67Ga, and /sup 99m/Tc pyrophosphate (TcPYP) scintigraphy. Myocardial TcPYP uptake has not been reported previously in sarcoidosis. In this patient, TcPYP was as useful as gallium scanning and thallium imaging in documenting the myocardial process

  11. Comparative value and limitations of thallium-201 and technetium-99m-pyrophosphate myocardial imaging in acute myocardial infarction

    International Nuclear Information System (INIS)

    Comparing the results of 201Tl and sup(99m)Tc-pyrophosphate myocardial imaging in patients with acute myocardial infarction, it is evident that both imaging techniques provide different information and each has its own advantages and disadvantages. For the practical application in the coronary care unit, it is essential to realize that each method yields its best results at different time intervals after onset of myocardial infarction. (Auth.)

  12. Safety, hemodynamic profile, and feasibility of dobutamine stress technetium myocardial perfusion single-photon emission CT imaging for evaluation of coronary artery disease in the elderly

    OpenAIRE

    Elhendy, A. A.; Bax, J. J.; Valkema, R.; Reijs, A. E. M.; Krenning, E. P.; Roelandt, J. R. T. C.; Domburg, R. T.

    2000-01-01

    OBJECTIVES: Cardiovascular disease is the leading cause of morbidity and mortality in the elderly. The evaluation of coronary artery disease by exercise stress testing is frequently limited by the patient's inability to exercise. Although pharmacologic stress testing with dobutamine is an alternative, the safety of dobutamine myocardial perfusion scintigraphy in the elderly has not been previously studied. PATIENTS AND METHODS: ...

  13. Adenosine technetium-99m sestamibi single-photon emission tomography for the assessment of jeopardized myocardium early after acute myocardial infarction. Paradoxical scintigraphic underestimation of jeopardized myocardium in patients with a severe infarct-related stenosis

    International Nuclear Information System (INIS)

    In 51 patients with a recent (99mTc-sestamibi single-photon emission tomography (SPET) and dobutamine stress echocardiography (DSE) were performed and correlated with the presence of significant coronary artery stenosis on quantitative coronary angiography. Regional perfusion activity was analysed semi-quantitatively (score 0-4) on a 13-segment left ventricular model. DSE was used for the estimation of the infarct size (low-dose DSE) and for concomitant evaluation of ischaemia (high-dose DSE). A reversible perfusion defect within the infarct region was observed in 20 of the 37 patients with a significant infarct-related lesion (sensitivity of 54%) and only in one patient without a significant infarct-related lesion (specificity of 93%). Further analysis revealed that the scintigraphic assessment of jeopardized myocardium was fairly good in patients with a moderate (DS 51%-64%) infarct-related stenosis but was inadequate in patients with a severe (DS?65%) infarct-related stenosis, while the echocardiographic detection of ischaemia was not influenced by stenosis severity (sensitivity of 73% in both subgroups). This scintigraphic underestimation of jeopardized myocardium was mainly related to a severely impaired myocardial perfusion under baseline conditions, as was evidenced by a significantly more severe rest perfusion score in the infarct region in patients with a severe stenosis as compared to those with a moderenosis as compared to those with a moderate stenosis, while infarct size on echocardiography was similar for both subgroups. It may be concluded that early after an acute myocardial infarction, adenosine 99mTc-sestamibi SPET may underestimate reperfused but still jeopardized myocardium, particularly in patients with a severe infarct-related stenosis. In these patients the evaluation of the ischaemic burden on rest-stress scintigraphy is hampered by the presence of a severely impaired myocardial perfusion in resting conditions. (orig./MG). With 2 figs., 1 tab

  14. Impact of intracoronary injection of mononuclear bone marrow cells in acute myocardial infarction on left ventricular perfusion and function: a 6-month follow-up gated {sup 99m}Tc-MIBI single-photon emission computed tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Lipiec, Piotr [Medical University of Lodz, 2nd Department of Cardiology, Lodz (Poland); Medical University of Lodz, 2nd Department of Cardiology, Bieganski Hospital, Lodz (Poland); Krzeminska-Pakula, Maria; Plewka, Michal; Kasprzak, Jaroslaw D. [Medical University of Lodz, 2nd Department of Cardiology, Lodz (Poland); Kusmierek, Jacek; Plachcinska, Anna; Szuminski, Remigiusz [Medical University of Lodz, Department of Nuclear Medicine, Lodz (Poland); Robak, Tadeusz; Korycka, Anna [Medical University of Lodz, Department of Hematology, Lodz (Poland)

    2009-04-15

    We investigated the impact of intracoronary injection of autologous mononuclear bone marrow cells (BMC) in patients with acute ST elevation myocardial infarction (STEMI) on left ventricular volumes, global and regional systolic function and myocardial perfusion. The study included 39 patients with first anterior STEMI treated successfully with primary percutaneous coronary intervention. They were randomly assigned to the treatment group or the control group in a 2:1 ratio. The patients underwent baseline gated single-photon emission computed tomography (G-SPECT) 3-10 days after STEMI with quantitative and qualitative analysis of left ventricular perfusion and systolic function. On the following day, patients from the BMC treatment group were subjected to bone marrow aspiration, mononuclear BMC isolation and intracoronary injection. No placebo procedure was performed in the control group. G-SPECT was repeated 6 months after STEMI. Baseline and follow-up G-SPECT studies were available for 36 patients. At 6 months in the BMC group we observed a significantly enhanced improvement in the mean extent of the perfusion defect, the left ventricular perfusion score index, the infarct area perfusion score and the infarct area wall motion score index compared to the control group (p=0.01-0.04). However, the changes in left ventricular volume, ejection fraction and the left ventricular wall motion score index as well as the relative changes in the infarct area wall motion score index did not differ significantly between the groups. Intracoronary injection of autologous mononuclear BMC in patients with STEMI improves myocardial perfusion at 6 months. The benefit in infarct area systolic function is less pronounced and there is no apparent improvement of global left ventricular systolic function. (orig.)

  15. Evaluation of brain tumor by 99mTc-MIBI. Comparison study with 201Tl and predictivity of therapeutic effect

    International Nuclear Information System (INIS)

    We compared the detectability of 99mTc-MIBI and 201Tl-chloride for brain tumor in relationship with histopathology. We also evaluated correlation between therapeutic effect using ACNU, Cisplatine and the degree of MIBI tumor uptake. The subjects were 31 brain tumor histologically confirmed by operation or biopsy. Dual-isotope SPECT technique was performed at both 20 min and 180 min after tracer injection. A tumor to normal lung ratio on both early (ER) and delayed image (DR) and retention index (RI) were calculated. The positive rates of 99mTc-MIBI (90.3% and 77.4%) were comparable to that of 201Tl (90.3% and 80.6%). In the relationship with histopathology, both MIBI and Tl accumulated in 100% of glioblastoma (GBM), metastasis (meta), anaplastic astrocytoma and 25% of low grade astrocytoma on both early and delayed images. On semiquantitative analysis, there were no statistical significance among GBM, meta and anaplastic astrocytoma of ER, DR, RI in the both radiopharmaceuticals. However, both ER and DR in GBM tended to be higher than those of anaplastic astrocytoma. In spite of intense MIBI uptake, GBM patients died within six months except one patient. We concluded that MIBI can be helpful in detecting brain tumor as Tl. MIBI also might be useful in estimating the degree of malignancy in glioma. However intense MIBI uptake did not mean favorable therapeutic effect in patients with GBM treated with ACNU and Cisplatine. (autGBM treated with ACNU and Cisplatine. (author)

  16. Standardization of 201Tl and 55Fe radionuclides in a 4 (PC)-NaI(Tl) coincidence system

    International Nuclear Information System (INIS)

    In the present work the procedure for the standardization of radionuclides using the 4?(PC)-NaI(Tl) coincidence system was developed. The radionuclides selected were 201Tl, used in nuclear medicine, and 55Fe primary standard source, used for x-ray spectrometers calibration. The 4?(PC)-NaI(Tl) is composed of a 4 proportional counter operated at 0.1MPa coupled to two NaI(Tl) crystals. The 201Tl decays by electron capture process followed by a prompt gamma-ray. The disintegration rate was determined by extrapolation technique using two methods: electronic discrimination and external absorbers. The radioactive sources were prepared in a 20 ?g cm-2 thick Collodion film. The conventional electronic system was used. The observed events were registered by the TAC method. The 55Fe decays by electron capture process to the ground state of 55Mn, emitting x rays with around 6 keV. The standardization was obtained by the tracing method. This technique was applied using two radionuclides, which decay by electron capture process followed by a prompt gamma-ray, namely 51Cr and 54Mn, as tracers. Measurements with 1 and 2 aluminum foils, each 150 g cm-2 thick were carried out. The activity was obtained by extrapolation for zero thickness Al foil. The uncertainties were treated by means of matrix covariance methodology and takes into account all correlations involved. (author)

  17. Evaluation of coronary artery disease using myocardial thallium-201 imaging with single photon emission computed tomography during adenosine induced coronary vasodilation

    International Nuclear Information System (INIS)

    Adenosine-loaded Tl-201 myocardial SPECT was performed in consecutive 55 patients with suspected ischemic heart disease. Among these patients, 22 had cuncurrently exercise Tl-201 myocardial SPECT imaging for comparison. Adenosine was intravenously injected at a dose of 0.14 mg/kg/min continuously for 6 min, and 3 min after the stard of injection Tl-201 was injected via the different vein. Myocardial SPECT images were acquired at 5 min and 3 hr after the completion of intravenous injection of adenosine. Perfusion defect and the presence or absence of redistribution (RD) were visually interpreted from the short- and long-axial tomograms. Relative Tl-201 regional uptake ratios were quantitatively determined. Decreased systolic arterial pressure, increased heart rate, and slightly increased rate-pressure product were observed with adenosine injection. Chest pain (13 patients), head-ache (7), ST depression (17), and A-V block II were also seen; however, these symptoms rapidly disappeared with the withdrawal of adenosine. The findings by adenosine loading were concordent with those by exercise loading (91% for perfusion defect and 86% for presence or absence of RD). According to segments, both loading tests were concordent in 90% for persusion and 89% for RD. Both adenosine- and exercise-loaded imagings correlated well with regional Tl uptake by segements, the lowest value of Tl-201 defect, and extent score of Tl-201 defect. Adenosine-loaded imaging had a sensitivity of 100ne-loaded imaging had a sensitivity of 100%, a specificity of 88%, and an accuracy of 97% for detecting parenchymal coronary lesions in evaluable 39 patients. In evaluable 22 patients, the sensitivity, specificity, and accuracy were 100%, 83%, and 95% for adenosine-loaded imaging and 88%, 83%, and 86% for exercise-loaded imaging. Thus, adenosine-loaded Tl-201 myocardial SPECT may be a safety and useful method for diagnosing ischemic heart disease. (N.K.)

  18. Evaluation of left ventricular function and volume in patients with dilated cardiomyopathy : gated myocardial single-photon emission tomography (SPECT versus echocardiography.

    Directory of Open Access Journals (Sweden)

    Berk Fatma

    2005-01-01

    Full Text Available Background: Left ventricular function, volumes and regional wall motion provide valuable diagnostic information and are of long-term prognostic importance in patients with dilated cardiomyopathy (DCM. This study was designed to compare the effectiveness of 2D-echocardiography and gated single-photon emission tomography (SPECT for evaluation of these parameters in patients with DCM. Patients and Methods: Gated SPECT and 2D-echocardiography were performed in 33 patients having DCM. Gated SPECT data, including left ventricular volumes and left ventricular ejection fraction (LVEF, were processed using an automated algorithm. Standard technique was used for 2D-echocardiography. Regional wall motion was evaluated using both modalities and was scored by two independent observers using a 16-segment model with a 5-point scoring system. Results: The overall agreement between the two imaging modalities for the assessment of regional wall motion was 56% (298/528 segments. With gated SPECT, LVEF, end-diastolic volume (EDV, and end-systolic volume (ESV were 27±9%, 217±77 mL, and 163±73 mL, respectively, and 30±8%, 195±58 mL, and 137±48 mL with echocardiography. The correlation between gated SPECT and 2D-echocardiography was good (r=0.76, P< 0.01 for the assessment of LVEF. The correlation for EDV and ESV were also good, but with wider limits of agreement (r=0.72, P< 0.01 and r=0.73, P< 0.01, respectively and significantly higher values were obtained with gated SPECT (P< 0.01. Conclusions: Gated SPECT and 2D-echocardiography correlate well for the assessment of LV function and LV volumes. Like 2D-echocardiography, gated SPECT provides reliable information about LV function and dimension with the additional advantage of perfusion data.

  19. Clinical studies on the thallium-201 myocardial scintiphotography in the patients with ischemic heart diseases

    International Nuclear Information System (INIS)

    Thallium-201 (201Tl) myocardial scintiphotography was performed in 34 patients with myocardial infarction and 13 with angina pectoris. Changing pattern of 201Tl activity in various organs observed. Myocardial blood flow was calculated from the relation of these activities. The body surface radioactivity of 201Tl decreased rapidly in initial phase, it gradually slowed down then reached to plateau on the heart and the lungs, while it increased gradually on the liver and kidneys. In patients with congestive heart failure, blood clearance of 201Tl was delayed and radioactivity on the lung area was increased compared with normal case. MBF/CO (%) ratio was calculated by the following way. Soon after the injection of 201Tl, serial images including whole chest were taken one frame in each one second during 30 seconds. Total injected dose was calculated from the maximum radioactivity in the frame. Myocardial uptake was calculated by the anterior view subtracting the mediastinal activity as the background at 5 minutes after the injection. MBF/CO (%) ratio was calculated as the myocardial uptake divided by the activity of total injected dose. Its mean value were 3.49 +- 0.45% in normals, 2.84 +- 0.47% in myocardial infarction and 3.00 +- 0.37% in angina pectoris, respectively, which showed significant low values in the latter two groups. MBF (ml/min/m2) = MBF/CO (%) x Cardiac index (CI). The mean value of MBF was iac index (CI). The mean value of MBF was 100.4 +- 12.7 ml/min/m2 in normals, 80.5 +- 21.1 in myocardial infarction and 77.3 +- 15.4 in angina pectoris, respectively, showing also significant low values in the latter two groups. Especially, MBF was most significant low in the groups of myocardial infarction with high serum CPK values. (author)

  20. Kinetic analysis of 18F-fluorodihydrorotenone as a deposited myocardial flow tracer: Comparison to thallium-201.

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; O' Neil, James P.; La Belle, Michael; Huesman, Ronald H.; VanBrocklin, Henry F.

    2004-03-01

    The goal of this investigation was to assess the accuracy of 18F-fluorodihydrorotenone (18F-FDHR) as a new deposited myocardial flow tracer and compare the results to those for 201Tl. Methods. The kinetics of these flow tracers were evaluated in 22 isolated, erythrocyte- and albumin-perfused rabbit hearts over a flow range encountered in patients. The two flow tracers plus a vascular reference tracer (131I-albumin) were introduced as a bolus through a port just above the aortic cannula. Myocardial extraction, retention, washout, and uptake parameters were computed from the venous outflow curves using the multiple indicator dilution technique and spectral analysis. Results. The mean initial extraction fractions of 18F-FDHR (0.85 +- 0.07) and 201Tl (0.87 +- 0.05) were not significantly different, although the initial extraction fraction for 18F-FDHR declined with flow (P < 0.0001), whereas the initial extraction fraction of 201Tl did not. Washout of 201Tl was faster (P < 0.001) and more affected by flow (P < 0.05) than 18F-FDHR washout. Except for initial extraction fraction, 18F-FDHR retention was greater (P < 0.001) and less affected by flow (P < 0.05) than 201Tl retention. Reflecting its superior retention, net uptake of 18F-FDHR was better correlated with flow than 201Tl uptake at both one and fifteen minutes after tracer introduction (P < 0.0001 for both comparisons). Conclusion. The superior correlation of 18F-FDHR uptake with flow indicates that it is a better flow tracer than 201Tl in the isolated rabbit heart. Compared to the other currently available positron-emitting flow tracers (82Rb, 13N-ammonia, and 15O-water), 18F-FDHR has the potential of providing excellent image resolution without the need for an on-site cyclotron.

  1. Indistinguishability of independent single photons

    OpenAIRE

    Sun, F. W.; Wong, C. W.

    2008-01-01

    The indistinguishability of independent single photons is presented by decomposing the single photon pulse into the mixed state of different transform limited pulses. The entanglement between single photons and outer environment or other photons induces the distribution of the center frequencies of those transform limited pulses and makes photons distinguishable. Only the single photons with the same transform limited form are indistinguishable. In details, the indistinguish...

  2. Cardiac functional mapping for thallium-201 myocardial perfusion, washout, wall motion and phase using single-photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    A method for three-dimensional functional mapping of Tl-201 myocardial uptake, washout, wall motion and phase was developed using SPECT. Each parameter was mapped using polar display in the same format. Normal values were determined in Tl-201 exercise study in 16 patients. Myocardial counts were lower in the septum and inferior wall and the difference of counts between anterior and inferior walls were greater in man compared with the perfusion pattern in woman. Washout was slower at septum and inferior wall in man, and slightly slower at inferior wall in woman. In gated blood-pool tomography, length-based and count-based Fourier analyses were applied to calculate the parameters of contraction and phase. The results of both Fourier analyses generally agreed; however, the area of abnormality was slightly different. Phase maps were useful for the assessment of asynergy as well as in patients with conduction disorders. These cardiac functional maps using SPECT were considered to be effective for the understanding of three-dimensional informations of cardiac function. (author)

  3. Therapeutic effect of co-enzyme Q10 on idiopathic dilated cardiomyopathy: assessment by iodine-123 labelled 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid myocardial single-photon emission tomography

    International Nuclear Information System (INIS)

    It has been reported that myocardial mitochondrial function can be improved by the administration of co-enzyme Q10 (CoQ10). Recently, iodine-123 labelled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) was developed for metabolic imaging using single-photon emission tomography (SPET). This study was conducted to determine whether the therapeutic effects of CoQ10 on idiopathic dilated cardiomyopathy can be evaluated by BMIPP myocardial SPET. Fifteen patients, comprising 14 men and one woman (mean age: 64±12 years), were examined. CoQ10 was administered at 30 mg/day for a period of 35.7±12.4 days. BMIPP myocardial SPET was carried out before and after CoQ10 treatment. The count ratio of the heart (H) to the upper mediastinum (M) (H/M ratio) was calculated using a region of interest method with anterior planar imaging. Representative short-axis tomograms were divided into 27 segments (three slices x nine segments). Each segmental score was analysed semiquantitatively using a four-point scoring system (normal=0, mild low uptake=1, severe low uptake=2, defect=3). The H/M ratio showed a significant improvement, from 2.39±0.39 to 2.54±0.47, after treatment (P<0.05). The BMIPP total defect score after CoQ10 treatment was significantly decreased to 10.1±4.3, compared to 13.9±4.5 without CoQ10 treatment (P<0.001). However, the percent fractional shortening measured using echocardiography was not significantly different before and after CoQ treatment (19.2±8.1 and after CoQ treatment (19.2±8.1 vs 19.7±7.1). BMIPP myocardial SPET was confirmed to be sensitive in evaluating the therapeutic effects of CoQ10 in patients with idiopathic dilated cardiomyopathy. This method is unique, since the therapeutic effects can be estimated from the perspective of metabolic SPET imaging. (orig.). With 5 figs., 1 tab

  4. Sympathetic reinnervation in cardiac transplants: {sup 123}I-MIBG and {sup 201}Tl/{sup 99m}Tc-MIBI scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. H.; Oh, S. J.; Son, M. S.; Son, J. W.; Choi, I. S.; Shin, E. K.; Park, C. H. [Gachon Medical School, Gil Heart Cener, Inchon (Korea, Republic of)

    2000-07-01

    The purpose was to evaluate cardiac sympathetic reinnervation and hemodynamic changes after orthotopic heart transplantation (TPL). We performed 24 serial or followup cardiac 123I-MIBG imaging and rest 201Tl/99mTc-MIBI dipyridamole stress gated myocardial perfusion SPECT (g-MPS) in 15 patients (M:F=10:5;mean ages=34.5{+-}13.0 yr; idiopathic:rheumatic=14:1; one heart lung TPL)(10.80 {+-}11.88 (1-48) mo) after TPL 123I-MIBG imagings were performed in anterior position 15 minutes, 4 and 24 hours after i.v. injection of 148 MBq 123I MIBG. Image quantitation was based on the ratio of heart to mediastinal MIBG uptake (HMR) Compared to HMR on 15 min images (1.48 {+-} 0.28), neither four nor 24 hour delayed images (1.26 {+-} 0.23 vs. 1.06 {+-} 0.26: p<0.05, respectively, ANOVA) showed definite delayed localization of MIBG. 12 subjects with <13 (4.9 {+-}3.7) months after TPL had no visible 123I-MIBG uptake on early 15 min imaging however, 12 subjects with 13 to 48(28.6{+-}12.8) months had visible cardiac 123I-MIBG uptake (HMR: 1.65{+-}0.21 vs. 1.32{+-}0.26; p=0.002). One-year followup 123I-MIBG scintigraphy in nine pts showed significantly increased HMR(1.40{+-}0.31 to 1.61{+-}0.16, p<0.05) but a plateau was reached at HMR value of 2.0, which was still lower than 3.0 in normal controls. Plasma NE was increased according to I-123 MIBG myocardial uptake. Annual G-MPS detected an allograft atherosclerosis in one pt and showed progressive normalization of tachycardia and significant deterioration of LVEF and cardiac indices according to severity of rejection. To dipyridamole stress, transplant heats showed significant subnormal hemodynamic responses. Partial sympathetic late reinnervation can occur <1 year after TPL, and reached a plateau of two-third of normal value. G-MPS seems to be a useful screening test for the detection of allograft atherosclerosis and rejection.

  5. Single photon emission tomography imaging of myocardial oxidative metabolism with 15-(p-iodophenyl)pentadecanoic acid in patients with coronary artery disease and aorta-coronary bypass graft surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kropp, J.; Reichmann, K.; Biersach, H.J. (Bonn Univ. (Germany, F.R.). Inst. fuer Klinische und Experimentelle Nuklearmedizin); Likungu, J.; Kirchhoff, P.G. (Bonn Univ. (Germany, F.R.). Klinik fuer Herz- und Gefaesschirurgie); Knapp, F.F. Jr. (Oak Ridge National Lab., TN (USA). Nuclear Medicine Group); Reske, S.N. (Technische Hochschule Aachen (Germany, F.R.). Abt. fuer Nuklearmedizin)

    1991-07-01

    A total of 29 patients with coronary artery disease (CAD) were investigated with 15-(p-iodophenyl)-pentadecanoic acid I123 ({sup 123}I-IPPA) and sequential single photon emission tomography (SPET). Of these, 19 were studied after aorto-coronary bypass graft surgery. Some 13 patients without evidence of CAD served as a control group. Two SPET studies (early and late) were carried out within 45 min after intravenous administration of 200 MBq {sup 123}I-IPPA at peak sub-maximal exercise. Semi-quantification of uptake (related to perfusion) and turnover (linked to metabolism) was obtained by segmental comparison of oblique slices. Taking coronary arteriography as the 'gold standard', {sup 123}I-IPPA scintigraphy had the following figures of merit for sensitivity and specificity in the diagnosis of CAD: for the left anterior descending artery territory 93% and 95%, for the left circumflex artery region 96% and 92%, and for the right coronary artery territory 77% and 92%, respectively. In all, 90% of the reperfused myocardial segments showed an improvement of uptake. Of these, 61% exhibited increased turnover after revascularization and 39% had pathologic turnover and thus a dissociation of improvement of perfusion and oxidative metabolism after surgery. (orig.).

  6. Single photon emission tomography imaging of myocardial oxidative metabolism with 15-(p-iodophenyl)pentadecanoic acid in patients with coronary artery disease and aorta-coronary bypass graft surgery

    International Nuclear Information System (INIS)

    A total of 29 patients with coronary artery disease (CAD) were investigated with 15-(p-iodophenyl)-pentadecanoic acid I123 (123I-IPPA) and sequential single photon emission tomography (SPET). Of these, 19 were studied after aorto-coronary bypass graft surgery. Some 13 patients without evidence of CAD served as a control group. Two SPET studies (early and late) were carried out within 45 min after intravenous administration of 200 MBq 123I-IPPA at peak sub-maximal exercise. Semi-quantification of uptake (related to perfusion) and turnover (linked to metabolism) was obtained by segmental comparison of oblique slices. Taking coronary arteriography as the 'gold standard', 123I-IPPA scintigraphy had the following figures of merit for sensitivity and specificity in the diagnosis of CAD: for the left anterior descending artery territory 93% and 95%, for the left circumflex artery region 96% and 92%, and for the right coronary artery territory 77% and 92%, respectively. In all, 90% of the reperfused myocardial segments showed an improvement of uptake. Of these, 61% exhibited increased turnover after revascularization and 39% had pathologic turnover and thus a dissociation of improvement of perfusion and oxidative metabolism after surgery. (orig.)

  7. Comparison of low-dose dobutamine stress echocardiography and single photon emission computed tomography and delayed contrast MRI in the diagnosis of myocardial viability: Meta-analysis

    International Nuclear Information System (INIS)

    Objective: To assess the diagnostic value of different imaging methods including low- dose dobutamine stress echocardiography, SPECT and contrast enhancement MRI with Meta-analysis in the diagnosis of myocardial viability. Methods: Articles published from 1998 to 2008 were searched in Cochrane library, Medline, Embase database, OVID database and CNKI for relevant English and Chinese articles. According to the criteria for diagnostic research published by Cochrane Method Group on screening and diagnostic tests, each article was critically screened and appraised, including the absolute numbers of true-positive, false-negative, tree-negative, and false-positive. Statistical analysis was performed employing Meta-test. Heterogeneity was tested, pooled weighted sensitivity and specificity and the corresponding 95% CI were calculated. Characteristic (SROC) curve was performed and the area under the curve was calculated. Finally, sensitivity analysis was performed. Results: Twenty-one of 438 retrieved articles were included, in which there were ten articles about Low-dose dobutamine stress echocardiography, and six articles about 99Tcm-MIBL/99Tcm-Tetrofosmin SPECT, and six articles about contrast enhancement MRI, and one of both 99Tcm-MIBL/99Tcm-tetrofosmin SPECT and contrast enhancement MRI. All groups had heterogeneity, and a random effects regression was developed. The pooled weighted sssion was developed. The pooled weighted sensitivity and specificity and area under SROC curve for low-dose dobutamine stress echocardiography to diagnose myocardial viability was 0.73(0.62-0.82)/0.82 (0.77-0.86) and 87.07% respectively. They were 0.82 (0.59-0.94)/ 0.77 (0.64-0.86) and 86.97% for 99Tcm-MIBI/99Tcm-Tetrofosmin SPECT respectively, while they were 0.94 (0.86-0.97)/0.75 (0.66-0.83) and 91.41% for contrast enhancement MRI respectively. Conclusion: As noninvasive testing technologies, low-dose dobutamine stress echocardiography and 99Tcm-MIBI/99Tcm-tetrofosmin SPECT and delayed contrast enhanced MRI allow the identification of viable myocardium, but delayed contrast enhanced MRI showed significant different pooled sensitivity in comparison to low-dose dobutamine stress echocardiography. (authors)

  8. Clinical efficacy of 99mTc-tetrofosmin myocardial scintigraphy

    International Nuclear Information System (INIS)

    99mTc-tetrofosmin is a lipophilic, cationic diphosphine which has been developed for myocardial imaging. We examined 9 patients with ischemic heart disease including 3 angina pectoris (AP), 4 old myocardial infarction (OMI), 1 AP with OMI and 1 syndrome X. One patient was examined before and after operation. Three hundred seventy MBq of 99mTc-tetrofosmin was injected during exercise and 740 MBq at rest. And 74 MBq of 201Tl myocardial exercise and redistribution scintigraphy was also performed to compare with 99mTc-tetrofosmin myocardial scintigraphy. SPECT, multiple gated SPECT and anterior planar images were obtained in all cases. We calculated percent wall thickening (%WT) using multiple gated SPECT images. There was a decreased lung uptake in 99mTc-tetrofosmin planar images compared to 201Tl myocardial scintigraphy. Liver and Biliary system uptake in 99mTc-tetrofosmin images was decreased with intake of milk. Segmental comparison of SPECT images showed an agreement in 9/10 of the segment between 201Tl and 99mTc-tetrofosmin. We could obtain excellent quality of multiple gated SPECT images in all patients. We could calculate percent wall thickening (%WT) in all patients. We conclude that 99mTc-tetrofosmin myocardial scintigraphy should provide usefulness for detection of ischemic myocardium as same as 201Tl myocardial scintigraphy, although the bio myocardial scintigraphy, although the biologic characteristics of two agents were different. These data and excellent quality of multiple gated SPECT images suggest that 99mTc-tetrofosmin is a new 99mTc agent for evaluation of patients with ischemic heart disease. (author)

  9. Relationship between thallium-201 myocardial SPECT and findings of endomyocardial biopsy specimens in dilated cardiomyopathy

    International Nuclear Information System (INIS)

    The purpose of this study was to clarify which myocardial histological findings associated with dilated cardiomyopathy (DCM) are reflected in quantitative 201Tl myocardial SPECT. We obtained studied SPECT images from 21 patients with DCM 10 minutes and 2 hours after they received an injection of 111 MBq 201Tl at rest. We calculated the percent coefficient of variation of myocardial 201Tl counts [%CV(Tl)], the washout rate (WR), standard deviation of WR [SD(WR)], extent score (ES) and severity score (SS). We used image analysis to measure % fibrosis, % myocytes, the ratio of fibrous tissue to myocyte tissue (F/My), myocyte size and standard deviation of myocyte size [SD(My)] in left ventricular endomyocardial biopsy specimens. The %CV(Tl) was correlated with % fibrosis and F/My. The ES and SS also correlated with F/My. The correlation between SD(WR) and SD(My) was significant. The present findings suggest that %CV(Tl), ES and SS of rest 201Tl SPECT reflect myocardial fibrosis and that the standard deviation of washout reflects the distribution of myocyte size. (author)

  10. Attenuation correction by simultaneous emission-transmission myocardial single-photon emission tomography using a technetium-99m-labelled radiotracer: impact on diagnostic accuracy

    International Nuclear Information System (INIS)

    The aim of this study was to quantify the potential benefit of attenuation correction by simultaneous emission and transmission imaging for the detection of CAD of vessels supplying the inferoposterior wall segments. In 25 male patients with ?50% stenoses of the right coronary artery and/or circumflex artery but without significant narrowing of the left anterior descending artery, stress studies using technetium-99m tetrofosmin (400 MBq) were carried out with and without attenuation correction. A dual-head camera with L-shaped detector positioning was equipped with two scanning gadolinium-153 line sources. Tomograms were reconstructed and quantified using circumferential count rate profiles of myocardial activity. The profiles were compared with the respective normal ranges obtained from 25 male patients. In patients without CAD, the maximal differences in count density of different wall segments were reduced from 29.0% in non-corrected (NC) studies to 9.5% in attenuation-corrected (AC) studies. In particular, the inferoposterior and septal wall segments were represented by significantly increased relative count densities after attenuation correction. The effects of attenuation correction proved independent of body mass. In patients with CAD, segmental count densities were abnormal in 84% of the NC studies and 100% of the AC studies. In single-vessel disease the stenotic vessel was identified in 66% of cases by NC studies and in 100% by AC studies. In AC studies, thin 100% by AC studies. In AC studies, the extent and depth of defects exceeded those in NC studies. For the detection of CAD of the right coronary artery, the receiver operating characteristic (ROC) curves relating to the AC studies demonstrated improved discrimination capacity. ROC analysis of CAD detection yielded normalcy rates of 82% (NC) and 94% (AC) for the circumflex artery and 65% (NC) and 97% (AC) for the right coronary artery area at a sensitivity level of 95%. (orig./MG). With 3 figs., 5 tabs

  11. Precordial ST-segment depression during acute inferior myocardial infarction: clinical, scintigraphic and angiographic correlations

    International Nuclear Information System (INIS)

    The cause and associated pathophysiology of precordial ST-segment depression during acute inferior myocardial infarction (IMI) are controversial. To investigate this problem, electrocardiographic findings in 48 consecutive patients with acute IMI were prospectively compared with results of coronary angiography, submaximal exercise thallium-201 (201Tl) scintigraphy and multigated blood pool imaging, all obtained 2 weeks after IMI, and with clinical follow-up at 3 months. Patients were classified according to the admission ECG obtained 3.3 +/- 3.1 hours after the onset of chest pain. Twenty-one patients (group A) had no or 201Tl perfusion abnormalities (p201Tl defects or wall motion abnormalities in anterior or septal segments

  12. Comparative accuracy of various Tl-201 reinjection imaging protocols to detect myocardial viability

    International Nuclear Information System (INIS)

    The conventional exercise-3 hours-redistribution thallium-201 [201Tl] imaging protocol has been recognized to be suboptimal for reliable detection of myocardial viability. Although 201Tl rest-reinjection after exercise has improved detection of viable myocardium, it is still underestimated in some patients. The present study was designed to compare detection of viable myocardium in five separate imaging steps: step 1: initial-exercise imaging, step 2: delayed-exercise imaging, step 3: Tl-201 reinjection imaging after delayed-exercise imaging, step 4: separate day rest-reinjection imaging, and step 5: separate day delayed-rest imaging. The study group consisted of 22 patients scheduled for coronary revascularization (either percutaneous transluminal coronary angioplasty or coronary bypass surgery). Pre -and postintervention echocardiographic wall motion and thickness served as independent markers of myocardial viability. Accuracy in identifying myocardial viability gradually improved incrementally from 201Tl imaging step 1 to step 5. The positive predictive value, negative predictive value and overall accuracy were best for the separate day delayed-rest study (step 5) at 90%, 33% and 78%, respectively. Myocardial segments had fixed defects on separate day delayed-rest 201Tl imaging (step 5), but nevertheless echocardiographic evidence of myocardial viability indicated less severe defects than segments judged nonviable by echocts than segments judged nonviable by echocardiography (p=0.021). The overall accuracy of separate day delayed-rest imaging (step 5) in predicting viability improved to 88% when segments with moderate or mild defects were considered viable. In conclusion, the most reliable predictor of myocardial viability with 201Tl imaging is defect severity on separate day delayed-rest images. (author)

  13. Detection of coronary artery disease using 12-lead electrocardiogram and simultaneous dual myocardial imaging with iodine-123-?-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 in patients with unstable angina

    International Nuclear Information System (INIS)

    We investigated the usefulness of 12-lead electrocardiogram and simultaneous single-photon emission computed tomography (SPECT) with 123I-?-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 (201Tl) for detecting coronary artery disease (CAD) in 54 consecutive patients with unstable angina. Discordant BMIPP uptake was defined as less 123I-BMIPP uptake than 201Tl uptake in 123I-BMIPP/201Tl dual SPECT. In the detection of CAD, ischemic electrocardiographic change during anginal attack had high sensitivity and low specificity, while discordant BMIPP finding had low sensitivity and high specificity. In patients showing ST depression during anginal attack, discordant BMIPP uptake showed high sensitivity and high specificity for detecting CAD. In conclusion, both 12-lead electrocardiogram during anginal attack and discordant BMIPP uptake are useful in detecting CAD in patients with unstable angina. (author)

  14. Defect images in stress thallium-201 myocardial scintigraphy in patients with complete left bundle branch block. Comparison of exercise stress and pharmacological stress

    International Nuclear Information System (INIS)

    Stress thallium-201 (201Tl) myocardial scintigraphy can demonstrate perfusion abnormalities, especially in the septum in patients with complete left bundle branch block (CLBBB) even with angiographically normal coronary arteries. Differences in the images between exercise and pharmacological stress 201Tl myocardial scintigraphy were evaluated in patients with CLBBB and normal coronary arteries. Forty-five patients with CLBBB underwent exercise stress using treadmill or pharmacological (adenosine triphosphate) stress 201Tl myocardial scintigraphy from October 1997 to February 2003. Patients with myocardial diseases were excluded, such as cardiomyopathy and coronary artery diseases detected by echocardiography and/or cardiac catheterization. The myocardial segment was classified according to the American Heart Association style for coronary artery disease. Peak blood pressure levels and heart rates were significantly higher in the exercise stress group than in the pharmacological stress group (p201Tl myocardial scintigraphy according to the stress method. Moreover, defects also occurred in areas other than the septum. Blood pressure and heart rate were involved in the mechanisms of defects in left bundle branch block. (author)

  15. Stress technetium-99m tetrofosmin myocardial scintigraphy. A new one-hour protocol for the detection of coronary artery disease

    International Nuclear Information System (INIS)

    A one-hour protocol for stress myocardial scintigraphy using technetium-99m (99mTc) tetrofosmin was compared with scintigraphy using thallium-201 (201Tl) for the detection of coronary artery disease in 43 consecutive patients who underwent stress 201Tl and 99mTc-tetrofosmin myocardial scintigraphy, and coronary arteriography within 1 week. For the stress 99mTc-tetrofosmin test, rest imaging data were acquired 20 min after intravenous injection of 5-7 mCi 99mTc-tetrofosmin, using a 3-head gamma camera collecting 20-sec views over 360deg. After dobutamine infusion or bicycle ergometer exercise, 20-25 mCi of 99mTc-tetrofosmin was additionally injected at peak stress. The stress images were acquired 15 min after the second injection with 5-sec views over 360deg. All patients also underwent 201Tl exercise and redistribution (4-hour) imaging following a standard protocol. The overall sensitivity for detecting coronary artery disease was 96.0%, with an overall specificity of 93.3% for both types of scintigraphy. Qualitative analyses of 21 conventionally divided left ventricular segments showed that the overall segmental concordance between the 99mTc-tetrofosmin and 201Tl imagings was 85.2% on the rest images and 82.1% on the stress images. The segmental concordance of the rest images was 87.0% in patients with neither significant stenosis nor myocardial infarction, 8cant stenosis nor myocardial infarction, 86.2% in patients with significant stenosis without myocardial infarction, and 82.9% in patients with significant stenosis and myocardial infarction, and the concordance values of the stress images were 85.4%, 87.5% and 75.6%, respectively. These preliminary results suggest that stress myocardial scintigraphy using the present new protocol is a promising approach for the detection of coronary artery disease, with diagnostic sensitivity and specificity comparable to those of stress 201Tl scintigraphy. (author)

  16. Iodine-123 phenylpentadecanoic acid and single photon emission computed tomography in identifying left ventricular regional metabolic abnormalities in patients with coronary heart disease: comparison with thallium-201 myocardial tomography

    International Nuclear Information System (INIS)

    Iodine-123 phenylpentadecanoic acid (IPPA) is a synthetic long chain fatty acid with myocardial kinetics similar to palmitate. Two hypotheses were tested in this study. The first hypothesis was that IPPA imaging with single photon emission computed tomography (SPECT) is useful in the identification of patients with coronary artery disease. Fourteen normal volunteers (aged 27 +/- 2 years) and 33 patients (aged 54 +/- 11 years) with stable symptomatic coronary artery disease and at least one major coronary artery with luminal diameter narrowing greater than or equal to 70% were studied with symptom-limited maximal exercise testing. The IPPA (6 to 8 mCi) was injected 1 min before the termination of exercise, and tomographic imaging was performed beginning at 9 min and repeated at 40 min after the injection of IPPA. Nine of the normal volunteers and 13 of the patients had a second examination performed at rest on another day. Using the limits of normal as 2 SD from the normal mean values, 27 of the 33 patients with coronary artery disease demonstrated abnormalities in either the initial distribution or the clearance of IPPA, or both. Nineteen of the 33 patients had a maximal variation of activity distribution of greater than or equal to 25% on the 9 min IPPA images. Twenty-two of the 33 patients had a maximal variation in IPPA washout greater than 17% and 17 had a washout rate less than or equal to 2%. There was good agreement between the location of significant coronary ween the location of significant coronary artery stenoses and abnormalities in the initial distribution and clearance of IPPA. The second hypothesis tested was that IPPA imaging is as or more sensitive and, therefore, complementary to thallium-201 imaging in the identification of exercise-induced ischemia in patients. Twenty-five of the 33 patients underwent both thallium-201 and IPPA tomographic imaging after symptom-limited maximal exercise testing

  17. Usefulness of 201Tl chloride quantitative gated SPECT in patients with cardiac sarcoidosis

    International Nuclear Information System (INIS)

    To examine the usefulness of thallium-201 quantitative gated SPECT (QGS) in patients with cardiac sarcoidosis, thirteen patients with systemic sarcoidosis, were examined by thallium-201 QGS and echocardiography. They were divided into two groups, A and B, with or without cardiac involvement of sarcoidosis according to the Japanese Ministry of Health and Welfare guidelines for cardiac sarcoidosis. Distribution abnormality was detected both in group A and group B, suggesting cardiac involvement caused by sarcoidosis in both groups, and the unreliability of these guidelines. The left ventricular (LV) wall was divided into 5 segments. The overall agreement between thallium-201 QGS and echocardiography for regional wall motion assessment of the LV was 72% (44/65 segments) suggesting the reliability of thallium-201 QGS for regional wall motion measurement. Among 44 segments with distribution abnormality, 17 segments had wall motion abnormality. Distribution abnormality with wall motion abnormality may reflect irreversible myocardial damage such as scar-like lesion, whereas distribution abnormality without wall motion abnormality may reflect the inflammatory stage, which can respond to steroid therapy. Thallium-201 QGS plays an important role in the diagnosis and follow up of cardiac involvement in patients with sarcoidosis, since this method is noninvasive, can be performed repeatedly and is suitable for simultaneous assessment of regional/total function and myocardial damaegional/total function and myocardial damage of the left LV. (author)

  18. A study of states in 201Tl, 203Tl using the (d,3n?) reaction: a new 9/2- band

    International Nuclear Information System (INIS)

    The nuclei 201Tl, 203Tl were formed in (d,3n) reactions. Studies of the de-excitation ?-rays are described and level schemes are deduced for both isotopes. Evidence is presented for the existence in 201Tl of a rotational band built on the 9/2- isomeric state at 920 keV. The band is compared to the 9/2- bands occurring in the odd isotopes 191Tl-199Tl and is shown to be well described by a symmetric rotor-plus-particle model. The model predictions for the low-lying positive parity states are also considered and satisfactory agreement with experimental data is obtained. No 9/2- band was observed in 203Tl and possible interpretations of this result are presented. (author)

  19. Comparison of myocardial scintigraphy, myocardial lactate extraction and coronary sinus blood flow before after coronary artery bypass surgery

    International Nuclear Information System (INIS)

    Studies were performed to validate exercise and delayed rest (5 hours) TL-201 myocardial perfusion scanning for the detection of myocardial ischemia before and after coronary artery bypass surgery. In 15 patients (13 male, 2 female), mean age 53 +- 8 years 201-TL-scintigraphy were performed in four different positions before (mean: 3 months) and after (mean: 5 months) coronary artery bypass surgery. 201-TL-scintigrams were processed by computer-assisted quantitation. Transmyocardial lactate extraction was calculated from lactate concentration in the arterial and coronary sinus blood. Lactate extraction and coronary sinus blood flow were measured at rest and during supraventricular pacing. 33 bypass grafts were implanted with 27 postoperatively patent. In clearly reversible defect regions, 201-TL uptake and washout were significantly reduced (0.58 +- 0.03 SD and 0.62 +- 0.45, resp. compared to normal < 0.85 resp. < 0.90). In constant defect regions, only 201-TL uptake was diminished (0.61 +- 0.30) in the presence of a normal washout (1.03 +- 0.45). After coronary artery bypass surgery, 201-TL uptake increased significantly to 0.65 +- 0.60 (p < 0.001) in reversible defect regions, but remained unchanged in constant defect regions. Diminished washout became normal in most reversible defect regions with no change in constant defect regions. Preoperatively lactate extraction at rest was 20 +- 27% and decreased during pacing to -2 +- 26% (p < 0.01). After coronary artery by- 26% (p < 0.01). After coronary artery bypass surgery, lactate extraction at rest was 38 +- 15%, during pacing it decreased to 12 +- 48% (n.s.). Preoperatively coronary sinus blood flow increased from 128 +- 22 ml/min to 208 +- 63 ml/min. (orig./APR)

  20. Evaluation of primary lung cancer and mediastinal lymph node metastasis using 99mTc-MIBI. Comparison with 201Tl and relation to chemotherapeutic effect

    International Nuclear Information System (INIS)

    We compared the detectability of 99mTc-MIBI and 201Tl-chloride for primary lung cancer and mediastinal lymph node metastasis. We also analyzed the relationship between 99mTc-MIBI uptake and effectiveness of chemotherapy in patients with small cell lung cancer. The subjects were forty-six primary lesions and 8 mediastinal metastatic lymph nodes confirmed by operation, and dual-isotope SPECT technique was performed at both 20 min and 180 min after tracer injection. A tumor to normal lung ratio on both early (ER) and delayed image (DR) and retention index (RI) were calculated. The positive rates of 99mTc-MIBI(early; 82.6%, delayed; 54.3%) were comparable to 201Tl in most primary tumor (87.0% and 84.8%). Whereas tumor smaller than 3 cm diameter was poorly visualized on both 99mTc-MIBI (25% and 0%) and 201Tl and (37.5% and 37.5%). Detectabilities of metastatic mediastinal lymph nodes of 99mTc-MIBI (62.5% and 25.0%) was comparable to those of 201Tl (62.5% and 50.0%). Regarding effectiveness of chemotherapy, NC group showed lower uptake of 99mTc-MIBI and significant lower value of RI compared to PR group. We concluded that early image of 99mTc-MIBI SPECT can be helpful in detecting primary lung cancer and metastatic mediastinal lymph node. Additionally, it might be useful for predicting the effects of chemotherapy in small cell lung cancer. (author)in small cell lung cancer. (author)

  1. Use of 99mTc-MIBI scintigraphy in the evaluation of the response to chemotherapy for osteosarcoma. Comparison with 201Tl scintigraphy and angiography

    International Nuclear Information System (INIS)

    In the treatment of osteosarcoma, the chemotherapeutic effect influences decisions regarding the surgical margin, continuation of chemotherapy, and choice of anticancer drugs for further chemotherapy. Therefore, it is necessary to evaluate the response to chemotherapy in the middle of the chemotherapy course. In this study, we investigated the use of 99mTc-hexakis-2-methoxyisobutyl-isonitrile (99mTc-MIBI) scintigraphy in evaluating the response to chemotherapy of patients with osteosarcoma in comparison with 201Tl scintigraphy and angiography. A total 45 patients with osteosarcoma were examined using 99mTc-MIBI scintigraphy, 201Tl scintigraphy, and angiography to evaluate their response to chemotherapy. The percentage reduction in the uptake ratios (?UR) calculated as 100 x [(prechemotherapy value - postchemotherapy value)/prechemotherapy value] were compared with histological assessments. Similarly, changes in tumor vascularity assessed by angiograms were compared with histological assessments. On the angiographic findings, the results were classified as complete response (CR), partial response (PR), no change (NC), or progressive disease (PD). On the images, ?UR in 99mTc-MIBI ?30% and ?UR in 201Tl ?30% were classified as responder, as were CR and PR in angiograms. The therapeutic effect was assessed by histopathological examination of the resected specimens. The tumors of poor responpecimens. The tumors of poor responders showed less than 90% necrosis, whereas the tumors of good responders showed 90% or more necrosis. Sensitivity, specificity, and accuracy were 73.9, 84.2, and 78.6%, respectively, for 99mTc-MIBI (?=0.57); 80.0, 61.1, and 72.1%, respectively, for 201Tl (?=0.42); and 91.7, 35.0, and 65.9%, respectively for angiography (?=0.28). 99mTc-MIBI could be effectively used to predict the final response to chemotherapy of osteosarcoma. (author)

  2. An approach based on the SIR measurement model for determining the ionization chamber efficiency curves, and a study of 65Zn and 201Tl photon emission intensities

    International Nuclear Information System (INIS)

    The measurement model used to determine ionization chamber efficiency curves accounts from the outset for impurity corrections and beta spectrum shapes. The curves are represented by exponentials of polynomials whose coefficients are adjusted using non-linear least-squares minimization. The curves are validated by comparing with SIR key comparison reference values (KCRVs) and other published curves. The associated covariance matrix is also evaluated. Deviations from model predictions for 65Zn and 201Tl using recommended nuclear data are studied

  3. Adsorption kinetics of {sup 201}Tl and migration of {sup 99m}Tc in natural soils; Cinetica de adsorcion de {sup 201}Tl y migracion de {sup 99m}Tc en suelos naturales

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez N, C. E. [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Fraccionamiento La Virgen, 52149 Metepec, Estado de Mexico (Mexico); Monroy G, F.; Fernandez R, E.; Anguiano A, J., E-mail: estefany_rodriguezn@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    The safety is very important in facilities where radioactive wastes are stored. One of the necessary characteristics of the site where these wastes will be disposed is the soil permeability, since a waterproof terrain avoids the diffusion and radionuclide transport in the leakages case. The objective of this work is to study the adsorption kinetics of {sup 201}Tl and the migration of {sup 99m}Tc in natural soil samples. The adsorption kinetics was determined starting from the obtaining of the retention coefficient of the thallium (static method) at different contact times. The technetium diffusion was studied by means of the dynamic method with different soil particles sizes. The results showed that the thallium is totally adsorbed starting from 20 h of contact among this and the mean. On the other hand, the technetium is very mobile in the soil, since it was possible to extract the majority of the tracer with little solvent. Also, it was found that for each soil gram the double water will be needed to leach the technetium almost in its entirety. Moreover, influence exists of the particle size in the migration velocity from the radiotracer to the most mobile being in major sizes than 2 mm that in minor size. (Author)

  4. Thallium-201 myocardial imaging in unstable angina and variant angina

    International Nuclear Information System (INIS)

    It is of clinical relevance in the coronary care unit to evaluate the potential role of 201Tl scintigraphy in patients with unstable angina. In the present chapter the authors discuss 1) the pattern of 201Tl scintigraphy in patients with unstable angina; and 2) the potential predictive value of 201Tl scintigraphy in identifying patients with unstable angina who have a poorer prognosis or greater tendency to subsequently develop acute myocardial infarction. All patients with unstable angina pectoris were purposely studied during the pain free period. It seemed conceivable that injecting 201Tl during an anginal attack would result in a high percentage of scintigraphic defects and probably diminish a potential discriminative value of the method. Moreover in clinical practice the majority of patients arrive at the coronary care unit some time after the last anginal attack. If a diagnostic test performed at this time could distinguish high and low risk patients, important therapeutic decisions might be made at the earliest possible times. (Auth.)

  5. Clinical evaluation of resting thallium-201 myocardial scintigraphy to detect chronic adriamycin cardiotoxicity against cardiac blood-pool scintigraphy

    International Nuclear Information System (INIS)

    To evaluate the reliability of thallium-201 (Tl) myocardial scintigraphy to detect chronic adriamycin (ADM) cardiotoxicity against ECG-gated cardiac blood-pool scintigraphy, single photon computed tomography (SPECT) of Tl at rest was performed on twelve patients who received ADM treatments and ten patients suspected of ischemic heart disease as controls. Although early SPECT images showed no patient as having a perfusion defect, the washout of Tl was observed to be slow throughout the myocardium of most patients. The Tl washout rate, determined from SPECT analysis, was significantly low in the ADM treated group compared to the control group and was negatively correlated with total ADM dosage. On the other hand, while the left ventricular ejection fraction (LVEF) obtained from the cardiac blood-pool scintigraphy was also significantly low in the ADM treated group when compared to the control group, there was no correlation with total ADM dosage. Furthermore, although six patients had a normal LVEF with a low washout rate, no patient had a normal washout rate with a low LVEF. The Tl washout rate may be a useful index to the early detection of chronic ADM cardiotoxicity. (author)

  6. Scintigraphic evaluation of coronary thrombolysis with urokinase using 201Tl-emission computed tomography

    International Nuclear Information System (INIS)

    Twenty-seven patients with first acute myocardial infarction were evaluated by serial determination of creatine kinase (CK) and thallium-201 myocardial emission computed tomography (ECT) performed four weeks after infarction. Total release of CK-MB and peak CK-MB had a linear correlation with infarct volume calculated by ECT, but a different relationship was found in between patients with successful coronary thrombolysis and those without. The former group of patients had an earlier peak of CK-MB and larger release of the cardiac enzyme comparative to infarct volume than the latter group. In 28 cases with proximal occlusion of the anterior descending coronary artery ECT-infarct volume was smaller with ealier recanalization within 10 hours after onset of infarction and, therefore, the time delay of recanalization may be allowed up to 10 hours. In conclusion, early coronary recanalization is an effective method to limit infarct size and time limit may be up to 10 hours after onset of infarction. But enzymatic calculation of infarct size should be modified when early coronary recanalization was expected. (author)

  7. Development of a computer-aided diagnosis system using fuzzy inference in 201TlCl exercise myocardial scintigraphy

    International Nuclear Information System (INIS)

    We have been working on the development of a computer-aided diagnosis system for images in nuclear medicine by using artificial neural networks. A physician's diagnosis of coronary artery disease in nuclear cardiology is performed not only on the basis of imaging data but also includes other factors such as measurement data from exercise scintigraphy. Therefore, we propose an expert system that uses fuzzy inference to estimate the number of abnormal vessels in cases of single- or multi-vessel disease (including normal vessels) of the coronary arteries. The main characteristic of this system is that it integrates information from various sources, including the physician's impressions. In this study, we investigated the system's clinical effectiveness. Results indicated a rate of agreement between the system's confidence level of inference and the physician's diagnosis of 62.2% and a rate of sensitivity of 83% for coronary artery disease. The computer made it possible to utilize vague factors such as a physician's assessment based on experience and intuition. These results demonstrate the usefulness of our proposed technique. (author)

  8. Myocardial perfusion in silent myocardial ischemia

    International Nuclear Information System (INIS)

    To investigate myocardial perfusion in silent myocardial ischemia, we performed exercise stress myocardial tomography with thallium-201 (Tl) in 85 patients with coronary artery disease (CAD). Exercise stress myocardial tomography was obtained both immediately after exercise and three hours later. Patients were classified into two groups according to the presence (Symptomatic Group, n=36) or absence (Silent Group, n=49) of chest pain during exercise stress. Clinical features (age, gender and history of myocardial infarction) and arteriographically determined severity of CAD were the same in both groups. The extent of myocardial ischemia (% Ischemia) estimated by exercise stress myocardial tomography was the same in each group (30±10 % in Silent Group, 28±12 % in Symptomatic Group, NS). The severity of exercise-induced myocardial ischemia was expressed as a minimal value of myocardial Tl washout rate (minimal WOR) of each patient. Although exercise heart rate was identical in both groups, minimal WOR in Silent Group was significantly higher than that of Symptomatic Group (4±10% vs -16±14%, p<0.001). The study in patients who exhibited both silent and symptomatic ischemia showed the same results. These findings suggest that the severity of ischemia is a fundamental factor in determining the presence or absence of pain during exercise induced ischemia. (author)

  9. Caffeine reduces dipyridamole-induced myocardial ischemia

    International Nuclear Information System (INIS)

    The mechanism of action of coronary vasodilation after dipyridamole may be based on inhibition of cellular uptake of circulating endogenous adenosine. Since caffeine has been reported to be a competitive antagonist of adenosine we studied the effect of caffeine on the outcome of dipiridamole-201Tl cardiac imaging in one patient. During caffeine abstinence dipyridamole induced myocardial ischemia with down-slope ST depressions on the ECG, and reversible perfusion defects on the scintigrams. When the test was repeated 1 wk later on similar conditions, but now shortly after infusion of caffeine (4 mg/kg), the ECG showed nodepressions, and the scintigrams only slight signs of ischemia. We conclude that when caffeine abstinence is not sufficient, the widespread use of coffee and related products may be responsible for false-negative findings in dipyridamole-201Tl cardiac imaging

  10. Single photon source characterization with a superconducting single photon detector.

    Science.gov (United States)

    Hadfield, Robert H; Stevens, Martin J; Gruber, Steven S; Miller, Aaron J; Schwall, Robert E; Mirin, Richard P; Nam, Sae Woo

    2005-12-26

    Superconducting single photon detectors (SSPD) based on nanopatterned niobium nitride wires offer single photon counting at fast rates, low jitter, and low dark counts, from visible wavelengths well into the infrared. We demonstrate the first use of an SSPD, packaged in a commercial cryocooler, for single photon source characterization. The source is an optically pumped, microcavity-coupled InGaAs quantum dot, emitting single photons at 902 nm. The SSPD replaces the second silicon Avalanche Photodiode (APD) in a Hanbury-Brown Twiss interferometer measurement of the source second-order correlation function, g(2)( ?). The detection efficiency of the superconducting detector system is >2 % (coupling losses included). The SSPD system electronics jitter is 170 ps, versus 550 ps for the APD unit, allowing the source spontaneous emission lifetime to be measured with improved resolution. PMID:19503303

  11. A study of thallium scintigraphy for myocardial infarction performed within 72 hours of attack

    International Nuclear Information System (INIS)

    In 40 cases undergoing 201Tl myocardial scanning within 72 hours of attack of myocardial infarction, a significant correlation was found between the infarct size determined by myocardial scanning and the size of the infarction estimated on the basis of ECG findings and serum enzymes. The group with high pulmonary capillary wedge pressure was the group with low Tl scores. The group showing dyskinesis and aneurysm in left ventriculography showed low Tl scores and a significant correlation between the ejection fraction calculated from left ventriculograms and the Tl score. The above date indicate that 201Tl myocardial scanning in the acute phase after attack of infarction reflects the infarction size and cardiac function. (Chiba, N.)

  12. Evaluation of the clinical usefulness of a new myocardial imaging agent, 99mTc-tetrofosmin (PPN1011)

    International Nuclear Information System (INIS)

    The clinical usefulness of a new myocardial perfusion imaging agent, 99mTc-1,2-bis [bis (2-ethoxyethyl) phosphino] ethane (99mTc-Tetrofosmin, (PPN1011) was evaluated in 355 patients with various heart diseases. Both 1 and 2 day protocols resulted in images that were significantly clearer than those of 201Tl. The absence of significant drug related adverse reaction supported the safety of the agent for clinical use. Regional abnormalities detected by coronary arteriography agreed with 99mTc-Tetrofosmin SPECT findings in 74% and with 201Tl SPECT in 78% of this study. Eighty-four percent of an abnormalities were detected with 99mTc-Tetrofosmin SPECT, as compared with those detected with 201Tl SPECT (88.4%). The complete concordance ratio between 99mTc-Tetrofosmin and 201Tl images in segmental analysis was 87-89% at rest and stress. Since 99mTc-Tetrofosmin SPECT was judged clinically useful in 93.2% (331/255) of the patients studied, it is concluded that 99mTc-Tetrofosmin is a promising agent for myocardial perfusion imaging. The simple labeling procedure without heating and cooling is suitable for emergency administration. Reconditioning of myocardial perfusion could be evaluated with 99mTc-Tetrofosmin injection before and after interventional therapy. These are additional features of the agent for clinical use. (author)linical use. (author)

  13. Evaluation of myocardial perfusion and ventricular shape in hypertrophic cardiomyopathy using 99mTc-tetrofosmin scintigraphy

    International Nuclear Information System (INIS)

    Hypertrophic cardiomyopathy (HCM) is known to have the impairment of myocardial perfusion as well as irregularly hypertrophic myocardium. To evaluate myocardial perfusion and ventricular shape in HCM, 99mTc-Tetrofosmin scintigraphy was performed after exercise (Ex) and at resting state (Re) in 10 patients with HCM and was compared with early image (Ea) and delayed image (De) of 201Tl scintigraphy performed after exercise. SPECT images of both 99mTc-Tetrofosmin and 201Tl scintigraphy were analyzed with five scaled visual scores set in 18 segments. The complete concordance ratio between 99mTc-Tetrofosmin (Ex and Re) and 201Tl(Ea and De) images in segmental analysis was 75%. Image quality of 99mTc-Tetrofosmin was seemed to be superior to that of 201Tl scintigraphy. In 9 patients with HCM, 99mTc-Tetrofosmin scintigraphy was performed under the ECG gating and the thickness of septal and free wall was measured. Good correlation was observed with the data by ultrasound cardiography (r=0.79, p99mTc-Tetrofosmin scintigraphy is useful for the evaluation of myocardial morphology as well as perfusion abnormality. (author)usion abnormality. (author)

  14. Localization of exercise-induced myocardial ischemia with single view and biplanar radionuclide ventriculography: Validation in single vessel coronary disease

    International Nuclear Information System (INIS)

    The ability of single view and biplanar radionuclide ventriculography (RVG) to determine the location of myocardial ischemia during maximal graded supine bicycle exercise was assessed in 50 patients with chest pain, no prior myocardial infarction, and a single coronary stenosis of >=50% luminal diameter narrowing at coronary angiography. A biplane collimator was used so that both right anterior oblique (RAO) gated first-pass and left anterior oblique (LAO) equilibrium RVG could be performed at rest and exercise. Results were compared with those obtained using 4-view 201Tl myocardial scintigraphy in the same patients. Regional wall motion abnormalities (WMA) and 201Tl perfusion defects were detected and assigned to individual coronary vessels by agreement of two of three independent observers, who read all studies blind along with those from control subjects with chest pain but no angiographically significant coronary artery disease. When scintigraphic abnormalities were detected, both biplanar RVG (36/39=92%) and 201Tl (25/25=100%) were more frequently correct in predicting the stenosed vessel than single view LAO RVG (24/32=75%) (P201Tl for localizing exercise-induced iscsup>Tl for localizing exercise-induced ischemic abnormalities to individual coronary stenosis. (orig.)

  15. Thallium-201 myocardial perfusion imaging during adenosine-induced coronary vasodilation in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Thallium-201 (201Tl) myocardial perfusion imaging during adenosine infusion was performed in consecutive 55 patients with suspected coronary artery disease. Adenosine was infused intravenously at a rate of 0.14 mg/kg/min for 6 minutes and a dose of 111 MBq of 201Tl was administered in a separate vein at the end of third minutes of infusion. Myocardial SPECT imaging was begun 5 minutes and 3 hours after the end of adenosine infusion. For evaluating the presence of perfusion defects, 2 short axis images at the basal and spical levels and a vertical long axis image at the mid left ventricle were used. The regions with decreased 201Tl uptake were assessed semi-quantitatively. Adenosine infusion caused a slight reduction in systolic blood pressure and an increase in heart rate. The rate pressure products increased slightly (9314±2377 vs. 10360±2148, p201Tl myocardial imaging during adenosine infusion was considered to be safe and useful for evaluating the patients with ischemic heart disease. (authoents with ischemic heart disease. (author)

  16. Routine exercise testing or thallium-201 scintigraphy for prediction of cardiac events post-myocardial infarction

    International Nuclear Information System (INIS)

    The efficacy of 12 lead exercise testing and rest/exercise 201Tl scintigraphy as indicators of coronary anatomy and prognosis was compared in 46 low risk survivors of acute myocardial infarction. The non invasive procedures were performed at discharge, and cardiac catheterization was performed six weeks post discharge. On exercise testing, ST depression in leads remote from the site of infarction was considered to indicate multivessel disease and reversible ischaemia. On 201Tl scintigraphy, a perfusion defect remote from the site of infarction indicated multivessel disease, while a defect which reperfused at rest indicated reversible ischaemia. During the mean follow-up of 13±3 months, 14 (30%) patients experienced cardiac events. Thallium scintigraphy was a more sensitive, but less specific, indicator of multivessel disease than exercise testing. Both exercise testing and 201Tl scintigraphy had a similar sensitivity (79% vs 79%), specificity (78% vs 88%) and predictive accuracy (78% vs 85%) for predicting subsequent cardiac events. Thus, in our patient population, 201Tl scintigraphy could not be demonstrated to be superior to routine exercise testing in low risk patients post myocardial infarction. (orig.)

  17. Basal kinetic studies of Tc-99m DMPE as a myocardial imaging agent in the dog

    International Nuclear Information System (INIS)

    Newly synthesized /sup 99m/Tc dichlorobis(1,2-dimethylphosphino)ethane (DMPE) was investigated as a myocardial imaging agent with respect to its kinetics (dependent on both time and regional coronary blood flow), its percent organ uptake, and its imaging characteristics in the anesthetized dog. Most of these data are compared with those of 201Tl. Blood clearance of the two agents is essentially the same. Compared with 201Tl, /sup 99m/Tc DMPE shows faster overall kinetics, higher heart-to-lung ratio, equally good correlation with a wide range of regional blood flows, and higher liver uptake. At the time of peak myocardial uptake, the mean heart uptake of 201Tl is 4.3%, compared with 2.9% for /sup 99m/Tc DMPE, yet only 0.9% uptake of /sup 99m/Tc DMPE is found in the lung as compared with 3.3% for 201Tl. These differences result in a heart-to-lung ratio of 2:1 for /sup 99m/Tc DMPE and 1:1 for 201Tl, based on the data obtained from the time-activity curve. The quantitative findings are supported by the superior quality of /sup 99m/Tc DMPE images of both normal and infarcted dog heart. The high hepatic uptake of /sup 99m/Tc DMPE is not a serious problem if images are obtained within 5-60 min after dose. These basic kinetic studies suggest that /sup 99m/Tc DMPE is a promising myocardial imaging agent

  18. Clinical application of 99mTc-tetrofosmin myocardial SPECT. A multicenter trial

    International Nuclear Information System (INIS)

    We performed a multicenter trial of 99mTc-tetrofosmin myocardial SPECT for the assessment of acute thrombolysis, pre and post elective PTCA and myocardial viability in comparison with 201Tl myocardial SPECT. The participants consisted of 212 patients at 44 institutions and the study lasted for 10 months. In assessing acute thrombolysis, the perfusion defect from the acute to subacute phase was reduced by 25% and that from the subacute to chronic phase by 10%. The mean perfusion defect score at subacute and chronic phase was well correlated with regional wall motion. The mean defect score during the subacute phase could predict future wall motion abnormalities. In assessing pre and post PTCA, 99mTc-tetrofosmin stress/rest myocardial SPECT could identify the changes of perfusion as in the case with successful PTCA and/or restenosis. In assessing the myocardial viability, 99mTc-tetrofosmin rest myocardial SPECT was superior to 201Tl redistribution, and equal to 201Tl reinjection method. In summary, we concluded that 99mTc-tetrofosmin is a powerful tool, with which to diagnose and manage patients with coronary artery diseases. (author)

  19. Diagnostic value of adenosine-induced left ventricular diastolic dysfunction for detecting coronary artery restenosis in patients undergoing stent implantation by stress ECG-gated myocardial perfusion SPECT. A pilot study

    International Nuclear Information System (INIS)

    Usefulness of diastolic dysfunction after adenosine stress for detecting coronary stenosis has not been defined. The diagnostic accuracy of a combination of myocardial perfusion and diastolic function, as defined by prolongation of time to peak-filling rate (TTPF)/R-R and myocardial perfusion alone for the detection of coronary restenosis, was evaluated. We used rest 201Tl/ adenosine stress 99mTc-tetrofosmin myocardial perfusion single-photon emission computed tomography (SPECT) in 70 patients. Patients were divided into the following 4 groups: 20 patients with normal SPECT without stent (Control group), 20 patients showing normal SPECT without coronary restenosis (Group 1), 16 patients showing significant coronary restenosis and myocardial ischemia (Group 2a) and 14 patients showing significant coronary restenosis without myocardial ischemia (Group 2b). The TTPF, which was calculated by quantitative gated SPECT (QGS)/R-R, was not different between after stress and at rest in Control group (0.18±0.02 vs 0.19±0.04, P=NS). The TTPF/R-R after stress was significantly lower than that at rest in Group 1 (0.17±0.02 vs 0.18±0.03, P<0.05), but TTPF/R-R after stress was significantly higher than that at rest in Groups 2a and 2b (0.22±0.03 vs 0.16±0.03, P<0.001 in Group 2a and 0.19±0.02 vs 0.16±0.02, P<0.001 in Group 2b, respectively). Diagnostic accuracy improved from 72% to 92% when prolongation of TTPF/R-R was taken into account (P<0.001). Diastaken into account (P<0.001). Diastolic dysfunction after stress was an accurate marker for detecting significant restenosis following stent implantation. (author)

  20. Comparison of regional myocardial extraction of 15-(p-123-I-phenyl)-pentadecanoic-acid (IPPA) with Tl-201 uptake pattern in normal and ischemic myocardium

    International Nuclear Information System (INIS)

    IPPA is catabolised via ?-oxidation to benzoic acid and has been shown to be a suitable tracer in myocardial studies of free fatty acid (FFA) metabolism. It was the aim of the present study to elucidate the behaviour of FFA extraction in ischemia. - In three normal subjects and in 20 patients with single vessel disease 201Tl and IPPA were simultaneously administered during fasting ergometry. In 10 patients the study was repeated after bypass surgery or PTCA. The initial accumulation of IPPA, related to that of 201Tl, normalized to applied activities, was considered to be a measure of the regional IPPA extraction (E). - In normal subjects, no significant differences in E between major myocardial segments were found. In patient with CAD, E was generally reduced in ischemic areas when compared with non-involved segments. In 5/20 patients the size of areas showing reduced IPPA-extraction matched that of reduced 201Tl uptake. In 15/20 patients the areas of reduced E were significantly larger than those in 201Tl images. In this group of patients, repeat studies pre- and postinfarction (3 pts) showed that the size of 201Tl defects arisen after infarction corresponded with that of reduced IPPA-extraction before infarction. Revascularisation produced an increase of both sup201Tl and IPPA uptake. However, in 7/10 pts IPPA extraction remained below the normal range. It is concluded that FFA extraction is reduces concluded that FFA extraction is reduced in ischemia. This reduced extraction is, in principle, reversible by revascularisation. There is some evidence that FFA extraction may serve as an indicator of jeopardized myocardium. (Author)

  1. The contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia. A study in patients with idiopathic dilated cardiomyopathy

    International Nuclear Information System (INIS)

    In order to know the contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia (VT), 123I-MIBG (meta-iodo-benzylguanidine) myocardial sympathetic nerve imaging was carried out in 52 patients with dilated cardiomyopathy (DCM) complicated with sustained VT (12 cases), non-sustained VT (18 cases) and VT(-) (22 cases). Myocardial SPECT at rest were done at 15 min after intravenous administration of 201Tl (111 MBq), and at 15 and 4 hr after intravenous administration of 123I-MIBG (111 MBq) with Toshiba GCA501 A/HG. Defects were scored for each image and difference of total defect scores (dTDS) between 201Tl and 123I was calculated. Echocardiography was also performed. dTDS was found significantly higher in sustained and non- sustained VT cases than VT(-) and thus myocardial sympathetic dysfunction or denervation was thought highly correlated with the genesis of VT in DCM. (K.H.)

  2. The contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia. A study in patients with idiopathic dilated cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Yoshio; Hirose, Yoshiaki; Fukuoka, Shuji; Shimozu, Junko; Takamiya, Makoto; Kamakura, Shirou; Miyatake, Kunio; Shimomura, Katsurou [National Cardiovascular Center, Suita, Osaka (Japan); Maeno, Masakazu

    1997-02-01

    In order to know the contribution of myocardial sympathetic dysinnervation in the genesis of ventricular tachyarrhythmia (VT), 123I-MIBG (meta-iodo-benzylguanidine) myocardial sympathetic nerve imaging was carried out in 52 patients with dilated cardiomyopathy (DCM) complicated with sustained VT (12 cases), non-sustained VT (18 cases) and VT(-) (22 cases). Myocardial SPECT at rest were done at 15 min after intravenous administration of 201Tl (111 MBq), and at 15 and 4 hr after intravenous administration of 123I-MIBG (111 MBq) with Toshiba GCA501 A/HG. Defects were scored for each image and difference of total defect scores (dTDS) between 201Tl and 123I was calculated. Echocardiography was also performed. dTDS was found significantly higher in sustained and non- sustained VT cases than VT(-) and thus myocardial sympathetic dysfunction or denervation was thought highly correlated with the genesis of VT in DCM. (K.H.)

  3. Myocardial scintigraphy with thallium-201

    International Nuclear Information System (INIS)

    In the case of an extended infarction of the anterior wall of the heart the ECG interpretation of an ischaemia is at least difficult if not impossible. The picture of a left bundle branch block evokes difficulties in the localisation of a myocardial infarction. Especially in these two manifestations of CAD there is an indication to perform myocardial imaging with thallium-201 at which ischaemic areas and infarction localisations can be determined exactly. With 25 well examined patients of a rehabilitation hospital these two subjects were clarified. 17 patients with an extended infarction of the anterior wall as shown by the ECG were examined in a first group. Myocardial imaging with 201Tl could prove the diagnosis of infarction in all patients. 12 of these patients showed a stress-depending ischaemia. With all 8 patients suffering from LBBB myocardial imaging could localize the area and size of the infarction. In two cases there also was a stress-depending ischaemia. (orig.)

  4. Thermoelectric single-photon detector

    Science.gov (United States)

    Kuzanyan, A. A.; Petrosyan, V. A.; Kuzanyan, A. S.

    2012-03-01

    The ability to detect a single photon is the ultimate level of sensitivity in the measurement of optical radiation. Sensors capable of detecting single photons and determining their energy have many scientific and technological applications. Kondo-enhanced Seebeck effect cryogenic detectors are based on thermoelectric heat-to-voltage conversion and voltage readout. We evaluate the prospects of CeB6 and (La,Ce)B6 hexaboride crystals for their application as a sensitive element in this type of detectors. We conclude that such detectors can register a single UV photon, have a fast count rate (up to 45 MHz) and a high spectral resolution of 0.1 eV. We calculate the electric potential generated along the thermoelectric sensor upon registering a UV single photon.

  5. Exercise study of thallium-201 myocardial imaging and coronary arteriography

    International Nuclear Information System (INIS)

    Myocardial imaging with intravenous thallium-201 (Tl) was performed following bycycle ergometer exercise (Ex) and redistribution study (Rd) was performed after 4 hours of injection in 16 patients suspected coronary artery disease (CAD). Of 5 patients with no or insignificant CAD (= 75% diameter stenosis, 6 with angina pectoris, 5 with old myocardial infarction), 6(55%) had Ex Tl defect (Sensitivity 55%), 5 of 6 patients (83%) had significant collateral circulation, and 7(64%) had Ex ST-segment depression. We conclude that positive Ex Tl-myocardial imaging is highly suggestive of CAD (Predictive value 100%). (author)

  6. The usefulness of dipyridamole thallium-201 single photon emission computed tomography for predicting perioperative cardiac events in patients undergoing non-cardiac vascular surgery

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the usefulness of dipyridamole Tl-201 myocardium single photon emission computed tomography (201Tl-SPECT) for predicting perioperative cardiac events in patients with arteriosclerosis obliterans (ASO) and abdominal aortic aneurysm (AAA) undergoing non-cardiac vascular surgery. Methods: Preoperative dipyridamole 201Tl-SPECT imaging in association with clinical risk assessment was performed in 224 consecutive patients (97 ASO and 127 AAA). Results: The patients were classified into three groups, including low-risk (n=173, 77%), intermediate-risk (n=39, 18%), and high-risk (n=12, 5%) groups according to the clinical risk stratification. The prevalence of reversible Tl-201 defect was significantly higher in the high-risk group than that in the low-risk group (83% vs. 14%, p<0.001). In 180 patients who underwent vascular surgery, 9 patients (5.0%) had perioperative cardiac events, including heart failure (n=l), unstable angina (n=2), and other cardiac events such as arrhythmias (n=6). The clinical variables including the clinical risk stratification did not significantly correlate with the perioperative cardiac events. In contrast, the reversible defect on 201Tl-SPECT was the only variable to predict perioperative cardiac events by a stepwise logistic regression analysis (odds ratio 7.0, 95% confidence interval l.7-28.0, p=0.007). It was also a significant predictor of perioperative cardiac events in a subgroup of low risk patients (odnts in a subgroup of low risk patients (odds ratio 11.6, 95% confidence interval 2.3-57.4, p=0.004). The sensitivity and specificity of the reversible defect for predicting perioperative cardiac events were 55.6% and 84.8% in all operated patients, and 57.1% and 89.7% in low risk patients, respectively. Conclusions: The preoperative dipyridamole 201Tl-SPECT was useful for predicting perioperative cardiac events in patients with vascular diseases, even in patients identified as having a low risk based on the clinical risk assessment. (authors)

  7. New Imaging Protocols for New Single Photon Emission CT Technologies

    OpenAIRE

    Slomka, Piotr J; Berman, Daniel S; Germano, Guido

    2010-01-01

    Nuclear cardiology practitioners have several new technologies available with which to perform myocardial perfusion single photon emission CT (MPS). These include dedicated small-footprint cardiac scanners, new stationary or semi-stationary three-dimensional detectors, and advanced software algorithms for optimal image reconstruction. These new technologies have been employed to reduce imaging time and radiation exposure. They require less technologist and camera time and offer improved patie...

  8. False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion

    International Nuclear Information System (INIS)

    The vasodilator effect of intravenously administered dipyridamole may be caused by an increase in endogenous plasma adenosine levels. The authors evaluated the effect of caffeine, an adenosine receptor antagonist, on the diagnostic results of dipyridamole-201Tl myocardial imaging in eight patients with coronary artery disease. Caffeine infusion significantly attenuated the dipyridamole-induced fall in blood pressure and the accompanied increase in heart rate. The infusion of dipyridamole alone resulted in chest pain and ST-segment depressions on the electrocardiogram in four patients, whereas none of these problems occurred when the tests were repeated after caffeine. In six of eight patients, caffeine was responsible for false-negative dipyridamole-201Tl tests. Semiquantitive scores of the dipyridamole-induced 201Tl perfusion defects were decreased by caffeine from 9.0 ± 0.9 to 2.0 ± 1.1 points (p less than 0.05). Computerized analysis revealed a caffeine-mediated reduction in the percent reversibility of the images from 46% ± 16% to 6% ± 10% (p less than 0.05). They conclude that the use of caffeinated products prior to dipyridamole-201Tl testing may be responsible for false-negative findings

  9. Comparison of 99mTc-(V)-DMSA, 201Tl and 99mTc-MIBI imaging in the follow-up of patients with medullary carcinoma of the thyroid

    International Nuclear Information System (INIS)

    Radionuclide scanning with tumour-seeking agents such as pentavalent technetium-99m dimercaptosuccinic acid [99mTc(V)-DMSA], thallium-201 and technetium-99m sestamibi (MIBI) has been reported to be useful in the detection of medullary thyroid carcinoma (MTC). We undertook a study in 14 MTC patients to determine the comparative imaging potential of 201Tl, MIBI and 99mTc(V)-DMSA in the detection of recurrent or metastatic MTC. All patients underwent total thyroidectomy and had persistently elevated serum calcitonin levels after the surgery. Scintigraphic studies were carried out 20 min after the injection of 111 MBq of 201Tl or 555 MBq of MIBI and 2 h following the injection of 370 MBq of 99mTc(V)-DMSA. All scintigraphic findings were correlated with contemporaneous CT or MRI studies. CT, MRI and bone scans showed 42 (26 bone, 16 soft tissue) metastatic sites in 11 of the 14 patients. In the remaining three patients no lesions were detected during diagnostic evaluation. 99mTc(V)-DMSA showed all of the soft tissue metastases but could not show two bone lesions. On the other hand, MIBI imaging was false-negative in 22 (52%) sites and 201Tl was false-negative in 34 (80%) sites. Overall, lesion detection sensitivities for 99mTc(V)-DMSA, MIBI and 201Tl were 95%, 47% and 19% respectively. We conclude that 99mTc(V)-DMSA is clearly superior to MIBI and 201Tl rly superior to MIBI and 201Tl in the follow-up of MTC patients. (orig.)

  10. Use of myocardial perfusion imaging and estimation of associated radiation doses in Germany from 2005 to 2012

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, O.; Burchert, W. [University Hospital of the Ruhr University Bochum, Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen (Germany); Bengel, F.M. [Hanover Medical School, Department of Nuclear Medicine, Hanover (Germany); Hacker, M. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Vienna (Austria); Schaefer, W. [Kliniken Maria Hilf GmbH, Clinic of Nuclear Medicine, Moenchengladbach (Germany); Collaboration: Working Group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine

    2014-05-15

    For several years the Working Group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine has been performing a regular survey to obtain information on technique, utilization and development of myocardial perfusion scintigraphy (MPS). Currently, data of six surveys from 2005 to 2012 are available. The aim of this paper is to deliver a general and comprehensive overview of all surveys documenting the course of patient doses over time and the development of the method. A one-page questionnaire with number of MPS patients, number of stress and rest MPS, referral structure and several technical issues was sent to all centres performing MPS in Germany and evaluated. With the data on protocol utilization, effective MPS patient doses were estimated. MPS per million population (pmp) varied between 2,380 and 2,770. In 2012, MPS pmp showed a slight increase for the first time. From 2005 to 2009 the angiography to MPS ratio increased from 3.4 to 4.4, and the revascularization to MPS ratio decreased from 0.66 to 0.53. In 2012, both indices demonstrated an opposite trend for the first time (4.1 and 0.55). A total of 108 centres participated in all surveys. They showed an increase in MPS patients of 4.0 % over the reporting period. In 2012, more than 50 % of the centres experienced no change or an increase in MPS numbers. The leading single competitor was MRI, followed by angiography and stress echocardiography. {sup 201}Tl studies have decreased since 2005 from 20 to 5 %. {sup 99m}Tc MPS studies showed a mild increase in 2-day protocols. In 2012, the average effective dose per patient was estimated at 7.4 mSv. Due to the decreasing use of {sup 201}Tl, a mild decline over the observation period can be documented. Dynamic exercise stress was the most common stress test and adenosine the leading pharmacological stress agent, with a growing percentage. In 2012, the regadenoson percentage was 9 %. Gated single photon emission computed tomography (SPECT) noted an increasing acceptance with >70 % in 2012. The segmental scoring of perfusion studies had a low acceptance. Ambulatory care cardiologists represented the major referral group. Germany has a moderate to moderate-high MPS utilization rate. Nevertheless, coronary artery disease (CAD) diagnosis and disease management are dominated by angiography. The survey data reveal a positive trend in MPS and a decrease in average patient dose reflecting good practice with guideline adherence, the implementation of technical improvements and success in training. (orig.)

  11. Use of myocardial perfusion imaging and estimation of associated radiation doses in Germany from 2005 to 2012

    International Nuclear Information System (INIS)

    For several years the Working Group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine has been performing a regular survey to obtain information on technique, utilization and development of myocardial perfusion scintigraphy (MPS). Currently, data of six surveys from 2005 to 2012 are available. The aim of this paper is to deliver a general and comprehensive overview of all surveys documenting the course of patient doses over time and the development of the method. A one-page questionnaire with number of MPS patients, number of stress and rest MPS, referral structure and several technical issues was sent to all centres performing MPS in Germany and evaluated. With the data on protocol utilization, effective MPS patient doses were estimated. MPS per million population (pmp) varied between 2,380 and 2,770. In 2012, MPS pmp showed a slight increase for the first time. From 2005 to 2009 the angiography to MPS ratio increased from 3.4 to 4.4, and the revascularization to MPS ratio decreased from 0.66 to 0.53. In 2012, both indices demonstrated an opposite trend for the first time (4.1 and 0.55). A total of 108 centres participated in all surveys. They showed an increase in MPS patients of 4.0 % over the reporting period. In 2012, more than 50 % of the centres experienced no change or an increase in MPS numbers. The leading single competitor was MRI, followed by angiography and stress echocardiography. 201Tl studies have decreased since 2005 from 20 to 5 %. 99mTc MPS studies showed a mild increase in 2-day protocols. In 2012, the average effective dose per patient was estimated at 7.4 mSv. Due to the decreasing use of 201Tl, a mild decline over the observation period can be documented. Dynamic exercise stress was the most common stress test and adenosine the leading pharmacological stress agent, with a growing percentage. In 2012, the regadenoson percentage was 9 %. Gated single photon emission computed tomography (SPECT) noted an increasing acceptance with >70 % in 2012. The segmental scoring of perfusion studies had a low acceptance. Ambulatory care cardiologists represented the major referral group. Germany has a moderate to moderate-high MPS utilization rate. Nevertheless, coronary artery disease (CAD) diagnosis and disease management are dominated by angiography. The survey data reveal a positive trend in MPS and a decrease in average patient dose reflecting good practice with guideline adherence, the implementation of technical improvements and success in training. (orig.)

  12. Single photon searches at PEP

    International Nuclear Information System (INIS)

    The MAC and ASP searches for events with a single photon and no other observed particles are reviewed. New results on the number of neutrino generations and limits on selectron, photino, squark and gluino masses from the ASP experiment are presented

  13. Using adaptive neuro-fuzzy inference system technique for crosstalk correction in simultaneous 99mTc/201Tl SPECT imaging: A Monte Carlo simulation study

    Science.gov (United States)

    Heidary, Saeed; Setayeshi, Saeed

    2015-01-01

    This work presents a simulation based study by Monte Carlo which uses two adaptive neuro-fuzzy inference systems (ANFIS) for cross talk compensation of simultaneous 99mTc/201Tl dual-radioisotope SPECT imaging. We have compared two neuro-fuzzy systems based on fuzzy c-means (FCM) and subtractive (SUB) clustering. Our approach incorporates eight energy-windows image acquisition from 28 keV to 156 keV and two main photo peaks of 201Tl (77±10% keV) and 99mTc (140±10% keV). The Geant4 application in emission tomography (GATE) is used as a Monte Carlo simulator for three cylindrical and a NURBS Based Cardiac Torso (NCAT) phantom study. Three separate acquisitions including two single-isotopes and one dual isotope were performed in this study. Cross talk and scatter corrected projections are reconstructed by an iterative ordered subsets expectation maximization (OSEM) algorithm which models the non-uniform attenuation in the projection/back-projection. ANFIS-FCM/SUB structures are tuned to create three to sixteen fuzzy rules for modeling the photon cross-talk of the two radioisotopes. Applying seven to nine fuzzy rules leads to a total improvement of the contrast and the bias comparatively. It is found that there is an out performance for the ANFIS-FCM due to its acceleration and accurate results.

  14. ECG gated thallium 201 myocardial images: Value in detecting multivessel disease in patients on anti anginal therapy 1-3 months after myocardial infarction

    International Nuclear Information System (INIS)

    ECG gated 201Tl scintigraphy was compared to non gated images for detecting 2-3 vessel disease 1-3 months after a first uncomplicated myocardial infarction. In all, 111 patients on anti anginal treatment underwent coronary arteriography and stress thallium imaging; 39 showed single vessel disease (SVD), and 72 multivessel disease (MVD). Sensitivity of black and white analog images was 82% for SVD and 8% for MVD. Sensitivity of computerized colored static images was 87% for SVD and 33% for MVD. For gated images, sensitivity was 100% and 92% in patients with SVD and MVD respectively. Specificity for detecting MVD was 95% for black and white images, 77% for computerized colored static images, and 69% for ECG gated images. Thus, ECG gated exercise 201Tl scintigraphy is useful for predicting the extent of coronary artery disease 1-3 months after myocardial infarction in patients on anti anginal therapy. (orig.)

  15. Assessment of myocardial fatty acid metabolism in patients with vasospastic angina using 123I-BMIPP myocardial SPECT

    International Nuclear Information System (INIS)

    Myocardial perfusion and fatty acid metabolism may be unpaired in the patients of vasospastic angina (VSA), because abnormal regional wall motion of left ventricle has been shown in some cases of VSA without apparent history of myocardial infarction. To study the clinical utility of 123I-BMIPP scintigraphy in diagnosis of myocardial ischemia in VSA, both 123I-BMIPP (rest) and 201Tl (exercise) SPECT were performed in the 20 patients of VSA diagnosed by coronary angiography. Defect scores were calculated visually from the 17 segments of myocardial images and were compared with patient's anginal history, period from last attack, numbers of attack, left ventricular (LV) ejection fraction and severity of regional LV wall motion abnormality. 123I-BMIPP SPECT images showed decreased tracer uptake in 14 cases of 20 (70%) VSA patients. Exercise 201Tl SPECT images showed decreased tracer uptake in 3 cases of 20 (15%) of patients. Severity of regional LV wall motion abnormality was correlated with defect score of BMIPP. Though total defect score of BMIPP did not correlate with patient's anginal history, number of symptoms and LV ejection fraction, correlated inversely with period from last attack. It was suggested that 123I-BMIPP myocardial SPECT images in VSA patients showed 'memories' of myocardial ischemic damages induced by vasospasm. In summary, 123I-BMIPP myocardial SPECT images could be a useful myocardial SPECT images could be a useful test for diagnosis and evaluation of VSA. (author)

  16. Imaging of cocaine-induced global and regional myocardial ischemia

    International Nuclear Information System (INIS)

    Severe and often fatal cardiac complications have been reported in cocaine users with narrowed coronary arteries caused by atherosclerosis as well as in young adults with normal coronaries. The authors have found that in normal dogs cocaine induces severe temporary hypoperfusion of the left ventricle as indicated by a significantly lower 201Tl concentration compared to the baseline state. The most significant decrease in uptake occurred 5 min after injection and was more pronounced in the septal and apical segments. Following intravenous administration of cocaine, instead of gradual disappearance of 201Tl from the left ventricle, there was continuous increase in 201Tl concentration in the left ventricle. These imaging experiments indicate that the deleterious effects of cocaine on the heart are probably due to spasm of the coronaries and decreased myocardial perfusion. Since spasm of the large subpericardial vessels does not seem to explain the magnitude of the increased coronary resistance and decreased coronary flow after cocaine as described in the literature, it is suggested that microvascular spasm of smaller vessels plays a major role in the temporary decrease in perfusion. The data may also suggest that severe temporary myocardial ischemia is probably the initiating factor for the cardiac complications induced by cocaine

  17. Quantification of leg muscle perfusion using thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    The purpose of this study is to quantify leg muscle perfusion with 201Tl single photon emission computed tomography (SPECT). Six normal controls and 21 patients with peripheral arterial disease underwent this examination. Thallium-201 leg SPECT of both stress and redistribution was performed using a dual-headed digital gamma camera. Each slice of transverse images was normalized with pixels and whole-body counts. In normal controls, the activity of posterior tibial muscle components was significantly higher than that of anterior tibial muscle components (p less than 0.001). In 14 components, where patients had insignificant lesions, profile curves were normal in 10 (71%). In 62 components, where patients had arteriographically significant lesions, stress profile curves were abnormal in 57 (92%) compared with normal controls. Approximately, in half (28/62) components which had significant lesions, profile curves showed redistribution after 3 hr compared with normal redistribution curves. In three patients who underwent successful bypass graftings, the activity of each muscle component returned to a normal range

  18. Factors affecting the myocardial activity acquired during exercise SPECT with a high-sensitivity cardiac CZT camera as compared with conventional Anger camera

    International Nuclear Information System (INIS)

    Injected doses are difficult to optimize for exercise SPECT since they depend on the myocardial fraction of injected activity (MFI) that is detected by the camera. The aim of this study was to analyse the factors affecting MFI determined using a cardiac CZT camera as compared with those determined using conventional Anger cameras. Factors affecting MFI were determined and compared in patients who had consecutive exercise SPECT acquisitions with 201Tl (84 patients) or 99mTc-sestamibi (87 patients) with an Anger or a CZT camera. A predictive model was validated in a group of patients routinely referred for 201Tl (78 patients) or 99mTc-sestamibi (80 patients) exercise CZT SPECT. The predictive model involved: (1) camera type, adjusted mean MFI being ninefold higher for CZT than for Anger SPECT, (2) tracer type, adjusted mean MFI being twofold higher for 201Tl than for 99mTc-sestamibi, and (3) logarithm of body weight. The CZT SPECT model led to a +1 ± 26 % error in the prediction of the actual MFI from the validation group. The mean MFI values estimated for CZT SPECT were more than twofold higher in patients with a body weight of 60 kg than in patients with a body weight of 120 kg (15.9 and 6.8 ppm for 99mTc-sestamibi and 30.5 and 13.1ppm for 201Tl, respectively), and for a 14-min acquisition of up to one million myocardial counts, the corresponding injected activities were only 80 and 186 MBq for 99mTc-sestamibi and 39 and 91 MBq for 201Tl, respectively. Myocardial activities acquired during exercise CZT SPECT are strongly influenced by body weight and tracer type, and are dramatically higher than those obtained using an Anger camera, allowing very low-dose protocols to be planned, especially for 99mTc-sestamibi and in non-obese subjects. (orig.)

  19. 201Tl, 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin: relative retention and clearance kinetics in retrogradely perfused guinea pig hearts

    International Nuclear Information System (INIS)

    Myocellular kinetics of 201Tl, 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin were investigated using retrogradely-perfused guinea-pig hearts. Relative retention decreased in the order 99mTc-MIBI ?? implies 99mTc-tetrofosmin ?? implies 99mTc-furifosmin. 201Tl and 99mTc-MIBI exhibited bi- (t1,t2), 99mTc-tetrofosmin and 99mTc-furifosmin triexponential (t1,t2,t3) time-activity-curves. Latest-phase elimination-half-life increased from 201Tl (t2) ?? implies 99mTc-MIBI (t2) ?? implies 99mTc-tetrofosmin (t3) ?? implies 99mTc-furifosmin (t3), showing a significant increase in deteriorating myocardium for all tracers but 99mTc-furifosmin. Delayed elimination in deteriorating myocardium explains at least partly the redistribution phenomenon of 201Tl, and suggests a similar phenomenon for 99mTc-MIBI and 99mTc-tetrofosmin

  20. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: A comparative dual-isotope study

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, R.; Rauch, B.; Kapp, M.; Neumann, F.J.; Seitz, F.; Kuebler, W. (Heidelberg Univ. (Germany). Dept. of Cardiology); Bubeck, B. (Heidelberg Univ. (Germany). Dept. of Nuclear Medicine); Mall, G. (Heidelberg Univ. (Germany). Dept. of Pathology); Tillmanns, H. (Giessen Univ. (Germany). Dept. of Cardiology); Stokstad, P.

    1992-11-01

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were adminstered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for {sup 201}Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r=0.75, p<0.001). Both tracers also revealed a similar sensitivity for the identification of individual coronary artery stenoses {>=}75% (IPPA: 70%, {sup 201}Tl: 66.3%, P=NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P=0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29%{+-}11% vs 44%{+-}11% in normal myocardium, P<0.05). The data indicate that serial myocardial scintigraphy with IPPA is essentially as sensitive as scintigraphy with {sup 201}Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability. (orig.).

  1. Engineered Quantum Dot Single Photon Sources

    CERN Document Server

    Buckley, Sonia; Vuckovic, Jelena

    2012-01-01

    Fast, high efficiency, and low error single photon sources are required for implementation of a number of quantum information processing applications. The fastest triggered single photon sources to date have been demonstrated using epitaxially grown semiconductor quantum dots (QDs), which can be conveniently integrated with optical microcavities. Recent advances in QD technology, including demonstrations of high temperature and telecommunications wavelength single photon emission, have made QD single photon sources more practical. Here we discuss the applications of single photon sources and their various requirements, before reviewing the progress made on a quantum dot platform in meeting these requirements.

  2. Engineered quantum dot single-photon sources

    International Nuclear Information System (INIS)

    Fast, high efficiency and low error single-photon sources are required for the implementation of a number of quantum information processing applications. The fastest triggered single-photon sources to date have been demonstrated using epitaxially grown semiconductor quantum dots (QDs), which can be conveniently integrated with optical microcavities. Recent advances in QD technology, including demonstrations of high temperature and telecommunications wavelength single-photon emission, have made QD single-photon sources more practical. Here we discuss the applications of single-photon sources and their various requirements, before reviewing the progress made on a QD platform in meeting these requirements. (review article)

  3. Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated by exercise stress myocardial 201Tl SPECT (EX-Tl). EX-Tl was performed before and after 8.8 weeks of oral verapamil (240 mg/day) in 12 patients with HCM who showed transient 201Tl perfusion defects under control conditions. 201Tl perfusion defect was visually scored and judged for 4 grades as normal (0), mild defect (1), moderate defect (2), and severe defect (3). Transient dilation index (TDI) was calculated as an index of subendocardial ischemia. Improvements of defect score were demonstrated in 10 patients after administration of verapamil. Two patients showed no change of defect score. Mean defect score decreased significantly from 5.50 to 3.03 (p<0.001). Although 11 of 12 patients showed abnormal TDI under control conditions, 10 of these revealed improvements of TDI and 7 of the 10 disclosed normal TDI after verapamil. Mean TDI decreased from 1.263 to 1.090 significantly (p<0.01). In conclusion, verapamil may improve myocardial ischemia in patients with HCM. (author)

  4. Quantitative single photon emission tomography

    International Nuclear Information System (INIS)

    Single photon emission tomography (SPET) is using nuclear medicine methods to allow functional imaging of organs. This paper describes realization of a quantitative SPET visualization, which can be achieved if gamma photon attenuation and scattering are included in the image reconstruction process. Iterative image reconstruction procedures, necessary for quantitative imaging, require knowledge of projection matrix. For its determination an efficient and clinically applicable model is proposed; the model treats both attenuation (based on known attenuation map) and multiple scattering (using buildup factors). Obtained results are compared with those obtained by MC simulation (author)

  5. Prognostic value of myocardial sympathetic activity in patients with asymptomatic myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Michihiro; Kurihara, Tadashi; Sindoh, Takashi; Sawada, Yoshihiro [Sumitomo Hospital, Osaka (Japan)

    1999-04-01

    To clarify the significance of myocardial sympathetic activity in patients with asymptomatic myocardial infarction (MI), we performed {sup 123}I-metaiodobenzyl-guanidine (MIBG) and {sup 201}Tl imaging at rest. We calculated the ratio of cardiac uptake of the isotope to the total injected dose (%Uptake), percent washout of MIBG over 3 hours and the Uptake Ratio (UR, %Uptake of MIBG divided by %Uptake of {sup 201}Tl). We compared these indices with clinical findings, exercise stress-rest myocardial perfusion imaging with {sup 99}Tc-methoxy-2-isobutyl isonitrile, coronary angiography, echocardiography and neurohumoral findings. During the follow-up period of 19.9{+-}10.3 months in 32 patients, events (heart failure or cardiac death) developed in 10 (31%). In univariate analysis, diabetes mellitus, atrial fibrillation, left ventricular end-diastolic dimension (LVDd) greater than 54 mm, and the %Uptake of MIBG and UR differed significantly between event and event-free groups. Cox proportional hazard model showed that the UR was a predictor of events (p=0.0007). In patients with UR less than 0.58, the relative risk of events was 19.1 times greater than in patients with an UR greater than 0.58. UR was closely correlated to LVDd (r=-0.578, p=0.01) suggesting that myocardial sympathetic activity is related to LV remodeling after MI. MIBG imaging provides important information regarding the prognosis and the pathophysiologic process of asymptomatic MI. (author)

  6. Prognostic value of myocardial sympathetic activity in patients with asymptomatic myocardial infarction

    International Nuclear Information System (INIS)

    To clarify the significance of myocardial sympathetic activity in patients with asymptomatic myocardial infarction (MI), we performed 123I-metaiodobenzyl-guanidine (MIBG) and 201Tl imaging at rest. We calculated the ratio of cardiac uptake of the isotope to the total injected dose (%Uptake), percent washout of MIBG over 3 hours and the Uptake Ratio (UR, %Uptake of MIBG divided by %Uptake of 201Tl). We compared these indices with clinical findings, exercise stress-rest myocardial perfusion imaging with 99Tc-methoxy-2-isobutyl isonitrile, coronary angiography, echocardiography and neurohumoral findings. During the follow-up period of 19.9±10.3 months in 32 patients, events (heart failure or cardiac death) developed in 10 (31%). In univariate analysis, diabetes mellitus, atrial fibrillation, left ventricular end-diastolic dimension (LVDd) greater than 54 mm, and the %Uptake of MIBG and UR differed significantly between event and event-free groups. Cox proportional hazard model showed that the UR was a predictor of events (p=0.0007). In patients with UR less than 0.58, the relative risk of events was 19.1 times greater than in patients with an UR greater than 0.58. UR was closely correlated to LVDd (r=-0.578, p=0.01) suggesting that myocardial sympathetic activity is related to LV remodeling after MI. MIBG imaging provides important information regarding the prognosis and the pathophysiologic process of asymptomatic MI. (authorlogic process of asymptomatic MI. (author)

  7. Better Randomness with Single Photons

    CERN Document Server

    Oberreiter, Lukas

    2014-01-01

    Randomness is one of the most important resources in modern information science, since encryption founds upon the trust in random numbers. Since it is impossible to prove if an existing random bit string is truly random, it is relevant that they be generated in a trust worthy process. This requires specialized hardware for random numbers, for example a die or a tossed coin. But when all input parameters are known, their outcome might still be predicted. A quantum mechanical superposition allows for provably true random bit generation. In the past decade many quantum random number generators (QRNGs) were realized. A photonic implementation is described as a photon which impinges on a beam splitter, but such a protocol is rarely realized with non-classical light or anti-bunched single photons. Instead, laser sources or light emitting diodes are used. Here we analyze the difference in generating a true random bit string with a laser and with anti-bunched light. We show that a single photon source provides more r...

  8. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: A comparative dual-isotope study

    International Nuclear Information System (INIS)

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were adminstered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for 201Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r=0.75, p201Tl: 66.3%, P=NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P=0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29%±11% vs 44%±11% in normal myocardium, P201Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis oabnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability. (orig.)

  9. Clinical evaluation of 3600 and 1800 data sampling techniques for transaxial SPECT thallium-201 myocardial perfusion imaging

    International Nuclear Information System (INIS)

    The most serious controversy regarding the application of transaxial SPECT technology to 201Tl myocardial perfusion imaging is the choice between 3600 compared with 1800 data sampling techniques. The present study utilized the original 3600 sampled raw data of 25 patients who had both SPECT 201Tl myocardial perfusion imaging and coronary angio/ventriculography for back projection reprocessing to accomplish the 3600/1800 comparison. The results show a high incidence, 36% (9/25), of false-positive segmental perfusion abnormality and a high incidence, 24% (6/25), of moderate to severe degree of image distortion with the 1800 data sampled reconstructed images. These were not observed in the 3600 data sampled reconstructed images. The above findings confirmed our previous preliminary conclusion that even though the 1800 data sampling technique has the advantage of providing improved image contrast and reduction in acquisition time it is not a reliable technique and should be abandoned

  10. Detection of hibernating myocardium in patients with myocardial infarction by low-dose dobutamine echocardiography. Comparison with thallium-201 scintigraphy with reinjection

    International Nuclear Information System (INIS)

    The identification of hibernating myocardium is important for selecting patients who will benefit from coronary revascularization. The relationship between echocardiographic and radioisotopic markers of hibernating myocardium and postrevascularization recovery of myocardial function was investigated in 21 patients who underwent successful revascularization. Each patient underwent low-dose dobutamine stress echocardiography and thallium-201 (201Tl) scintigraphy with reinjection before revascularization. The presence of contractile reserve in dobutamine stress echocardiography and Tl uptake in 201Tl scintigraphy with reinjection were defined as markers of hibernating myocardium. Follow-up echocardiograms were evaluated for improved regional wall motion in all patients at a mean of 8.6 months after revascularization. Sensitivity, specificity, and positive and negative predictive values of low-dose dobutamine stress echocardiography for indicating recovery of function after revascularization were 75.0%, 77.8%, 81.8%, and 70.0%, respectively. Sensitivity, specificity, and positive and negative predictive values of 201Tl scintigraphy with reinjection for indicating recovery of function after revascularization were 91.7%, 55.6%, 73.3%, and 83.3%, respectively. There were no statistical differences between low-dose dobutamine echocardiography and 201Tl scintigraphy in predicting postrevascularization recovery of function in patientsarization recovery of function in patients with hibernating myocardium. (author)

  11. Clinical usefulness of the technetium-99m/thallium-201 overlap on simultaneous dual SPECT in reperfusion after thrombolytic therapy for acute myocardial infarction

    International Nuclear Information System (INIS)

    In this study, the clinical usefulness of the technetium-99m/thallium-201 (99mTc-PYP/201Tl-Cl) overlap on simultaneous dual SPECT in reperfusion after thrombolytic therapy for acute myocardial infarction was evaluated. The subjects were 14 patients with acute myocardial infarction who had not had myocardial infarction. All patients had chest pain that persisted more than 1 hour and showed electrocardiographic ST elevation. Myocardial scintigraphy was performed on the 4th day of the attack, at 81±35 hours after reperfusion on average. Three hours 50 min after intravenous injection of 740 Mbq 99mTc-PYP, 111 Mbq 201Tl-Cl was intravenously injected, and simultaneous dual SPECT was performed after 10 min. In all short axis SPECT image which showed 99mTc-PYP accumulation, the area of 99mTc-PYP accumulation (Tc hot), the overlap area of 99mTc-PYP and 201Tl-Cl accumulation (overlap), and the total area of 99mTc-PYP and 201Tl-Cl accumulation in the short axis SPECT images were calculated. The relationships between these parameters and the peak creatinine kinase (CK), changes in wall motion abnormalities observed by M-mode echocardiography, and the 4-hour delayed image by 201Tl-Cl exercise scintigraphy performed about one month after the attack were evaluated. The results were both parameters of overlap/Tc hot and overlap/total were negatively correlated witrlap/total were negatively correlated with the peak CK, overlap/Tc hot and overlap/total were positively correlated with wall motion scores ratio (WMSR), and overlap/Tc hot was positively correlated with Tl uptake (d)/Tc hot, and the acute overlap region was evaluated to be viable cardiac muscles one month after the attack. These results demonstrated that the 99mTc-PYP/201Tl-Cl overlap on simultaneous dual SPECT in reperfusion after thrombolytic therapy for acute myocardial infarction indicates the presence of viable cardiac muscles, showing that this method is useful for judgment of the effects of reperfusion. (author)

  12. The (F) utility of the thallium-201 quantitative lung/myocardial ratio in the detection of coronary artery disease

    International Nuclear Information System (INIS)

    Exercise-induced increases in pulmonary uptake of thallium-201 (201Tl) have been associated with exercise-induced myocardial dysfunction. To evaluate this phenomenon more replicably, a quantitative semi-automated computer program was used to generate, from anterior exercise and delayed views, lung-myocardial ratios (LMR) of 201Tl uptake in 78 patients [40 normal, 38 with coronary artery disease (CAD)]. Patients with CAD had a significantly higher mean exercise lung myocardial ratio (EXLMR) than normals (30.8 vs. 27.3; P=85% of an age-adjusted maximal heart rate), the EXLMRs of CAD patients were significantly higher than those of normals (29.7 vs. 25.5; P=0.003). However, this difference between CAD and normal patients was not apparent in a patient subgroup with submaximal exercise levels (201Tl scans lacking visually defined perfusion defects (visually normal), an elevated LMR detected 60% of CAD cases with 81% specificity. A considerably elevated EXLMR in patients achieving adequate exercise should suggest the presence of CAD, even if there are no visually apparent cardiac perfusion defects. With submaximal exercise, however, the EXLMR is not a useful discriminator between CAD patients and normals. (orig.)nd normals. (orig.)

  13. Sympathetic reinnervation in cardiac transplants: 123I-MIBG and 201Tl/99mTc-MIBI scintigraphy

    International Nuclear Information System (INIS)

    Iodine-123 metaiodobenzylguanidine (123I-MIBG) is a norepinephrine (NE) analogue and taken up by myocardial sympathetic nerves. To determine whether cardiac sympathetic reinnervation occurs after orthotopic heart transplantation (TPL). We performed 24 serial or followup cardiac 123I-MIBG imaging and 201T1/99mTc-MIBI dipyridamole stress gated myocardial perfusion SPECT (g-MPS) in 15 pts(M : F =10 : 5; mean ages = 34.67±12.92 yr; idiopathic: rheumatic=14:1) (10.80±11.88 (1-48) mo) after TPL. 123I-MIBG imagins were performed in anterior position 15 minutes, 4 and 24 hours after i.v. injection of 148 MBq 123I MIBG. Image quantitation was based on the ratio of heart to mediastinal MIBG uptake (HMR). 12 subjects with 1 year after TPL whereas reinnervation is less likely to occur in pts with a pretransplantation diagnosis idiopathic cardiomyopathy

  14. The mechanism of giant negative T wave in electrocardiogram in patients with apical hypertrophic cardiomyopathy. Evaluation with thallium-201 and iodine-123 metaiodobenzylguanidine myocardial scintigraphy

    International Nuclear Information System (INIS)

    The aims of this study were to clarify the mechanism of giant negative T waves (GNT) in patients with apical hypertrophic cardiomyopathy (AHCM), using myocardial SPECT with thallium-201 (201Tl) and iodine-123 metaiodobenzylguanidine (123I-MIBG). Myocardial SPECT in 8 patients with AHCM, diagnosed with GNT in EKG and apical hypertrophy in echocardiogram, were compared with those in 7 normal subjects. The EKG in patients with AHCM showed tall R waves, GNT and ST segment depression in the left precordial leads. With the SPECT, the ratio of radioisotope activities apical ROI vs. other ROI (anterior, septal and lateral segments) were calculated. The ratio of 201Tl was high in AHCM, compared with that of normal subjects, suggested the increase in apical myocardial blood flow. The ratio of 123I-MIBG tended to be low in AHCM. The 201Tl/123I-MIBG ratio was high in the apical myocardium in AHCM, indicated low sympathetic nerve activities, though there was myocardial hypertrophy. We concluded that giant negative T waves in apical hypertrophic cardiomyopathy might be due to relatively low cardiac sympathetic nerve activities in apical myocardium with idiopathic hypertrophy. (author)

  15. Single photon sources for quantum information applications

    Science.gov (United States)

    Höfling, S.; Schneider, C.; Heindel, T.; Lermer, M.; Hoang, T. B.; Beetz, J.; Braun, T.; Balet, L.; Chauvin, N.; Li, L.; Reitzenstein, S.; Fiore, A.; Kamp, M.; Forchel, A.

    2012-03-01

    Efficient sources of indistinguishable single photons are a key resource for various applications in fields like quantum sensing, quantum metrology and quantum information processing. In this contribution we report on single photon generation based on III-V semiconductor quantum dots (QDs). To increase the emission efficiency of single photons, it is essential to tailor the radiative properties of the quantum dot emitters by engineering their photonic environment. We present optimized single photon emitters being based on both micropillar and photonics crystal cavities, for applications in a vertical platform and on-chip in-plane platform, respectively. Electrically driven single photon sources with self assembled semiconductor QDs embedded into GaAs/AlAs micropillar cavities emit on demand net rates of ~35 MHz single photons, thus being well exploitable in quantum key distribution systems. In order to establish also a spatially deterministic fabrication platform, position controlled quantum dots are integrated into p-i-n micropillar cavities and single photon emission of a coupled QD-micropillar diode system is observed. Efficient broadband coupling of single photons into photonic crystal waveguides provides the basis for all on-chip quantum information processing, and an according approach is reported.

  16. Measurement of the healing ability of ischemic ulcers in the lower limbs in chronic arterial obstructive disease using 201Tl-Cl

    International Nuclear Information System (INIS)

    Evaluation of the healing ability of ischemic ulcers by a method involving measurement of the ulcer index (U. I.) and mean ulcer index of toes (mU. I.) using 201Tl-Cl before and after the treatment of chronic arterial obstructive disease accompanied by ischemic ulcer was studied. The lesions consisted of 56 ulcers in 41 limbs. Reactive hyperemia following avascularization stress was used for measurement, and U. I. was determined according to the method of Siegel et al. For cases with toe ulcers, the mU. I. was measured from plantar scintigrams, twice under stress and upon redistribution after 3 hours' rest. The following results were obtained. 1) The healing ability of the cases with a U. I. value of more than 1.4 was good, but even among cases with a pretreatment U. I. of 0.9 - 1.4, ulcer healing was also good in cases in which the U. I. was maintained above 1.4 as a result of various treatments. 2) Significant increases in U. I. were observed in the arterial reconstruction group after treatment, compared to the conservative treatment group and the lumbar sympathectomy group. 3) The healing ability was good in cases with an mU. I. of more than 1.2 at stress except for 2 ASO cases complicated by diabetes. 4) Although it was difficult to prognosticate the healing ability of cases with an mU. I. of less than 1.2 before treatment, healing ability could be evaluated after treatment on the basis of the appearance of significant increase in blood flow on stress iificant increase in blood flow on stress in the ulcerated toes. 5) A stress index seemed to reflect the ischemic conditions in ulcerated toes in relation to stress. 6) U. I. and mU. I. measured using 201Tl-Cl were significantly correlated with the degree of inflammatory and reactive hyperemia in the floor of ulcers and in the ulcerated toes. (J.P.N.)

  17. Effect of long-term exercise training on regional myocardial perfusion changes in patients with coronary artery disease

    International Nuclear Information System (INIS)

    The effect of long-term exercise training on myocardial perfusion in coronary artery disease (CAD) patients was assessed using 201Tl exercise studies at a baseline (4 months after the onset of CAD) and at a 1-year or more follow-up in 58 patients with stable CAD. The subjects had been divided into a training group (n=35) participating in supervised exercise 2 times per week for the follow-up period, and the control group (n=23). There was an improvement in the myocardial perfusion on stress 201Tl scintigraphy in 20 of the 35 (57.1%) trained patients and in 3 of the 23 (13.0%) of the control patients. The number of 201Tl stress myocardial perfusion defect segments was significantly decreased after the cardiac rehabilitation training (231 to 153 segments), but showed no change in the control group (158 to 156 segments). In spite of no significant differences in the number of involved coronary arteries, it improved (12/17 patients: 70.6%) more in the patients who had trained for more than 2 years compared to the patients who had trained for less than 2 years. The exercise tolerance increased in 25 of the 35 training group patients (71.4%), and in only 3 of the 23 control group patients (13.0%). The peak double products increased from 20,131±6,010 to 28,370±5,600 in the training group, and showed no change in the control group (20,567±5,112 to 20,964±7,728). The results indicated that the long-term physical training increased exercise physical training increased exercise tolerance and the double products of CAD patients. In addition, the training resulted in improved cardiac perfusion as evidenced by 201Tl scintigraphy. The findings suggest that exercise training is an advisable and effective treatment for patients with CAD. (K.H.)

  18. Use of 99mTc-MIBI scintigram in the evaluation of the response of chemotherapy to malignant bone and soft tissue tumor. Comparison with 201Tl scintigram and angiogram

    International Nuclear Information System (INIS)

    All 64 patients with malignant bone or soft tissue tumors who were the subjects of this study were examined by 99mTc-methoxyisobutylisonitrile (MIBI) scintigram, 201Tl scintigram, and angiography to evaluate their response to chemotherapy. The percentage reductions in uptake ratios and the changes vascularity assessed by angiography were compared with histological assessments. Based on the angiographic findings the results were assessed as CR (complete response), PR (partial response), NC (no change), or PD (progressive disease). On the images, 99mTc-MIBI?25%, 201Tl?30% and CR/PR in the angiograms were assessed as responders. All tumors were surgically resected, and the therapeutic effect was assessed by histopathological examination of the resected specimen. The tumors of poor responders showed less than 90% necrosis, and the tumors of good responders showed 90% or more necrosis. Sensitivity, specificity, and accuracy were 86.7%, 91.2%, and 89.1%, respectively, for 99mTc-MIBI imaging, 80.0%, 70.6%, and 75.0%, respectively for 201Tl imaging, and 86.7%, 38.2%, and 60.9%, respectively for angiography. The results of this study showed that 99mTc-MIBI scintigram could be effectively used to predict the final response of malignant bone and soft tissue tumors to chemotherapy. (author)

  19. Effect of beta blockade on single photon emission computed tomographic (SPECT) thallium-201 images in patients with coronary disease

    International Nuclear Information System (INIS)

    We evaluated the effect of beta blockers on thallium-201 (Tl-201) single photon emission computed tomographic (SPECT) imaging in 12 patients with coronary disease using an automated computer algorithm. Maximal exercise heart rate and blood pressure were reduced and exercise time was increased with beta blockers. Estimated stress defect size decreased from 47 +/- 36.3 gm during placebo treatment to 32 +/- 27.1 gm during beta blocker therapy (-32%; p less than 0.01). The placebo treatment redistribution defect was estimated to be 28 +/- 29.8 gm. It fell to 15 +/- 23.3 gm with beta blockade (-46%; p less than 0.005). All patients had a stress Tl-201 defect during placebo treatment and eight had redistribution defects consistent with residual scar. During beta blocker therapy, 2 of 12 patients had normal stress-redistribution studies and only five patients had redistribution defects. Beta blockade can reduce exercise and redistribution Tl-201 SPECT defect size significantly while simultaneously increasing exercise time and reducing angina. Beta blockers may unmask or may eliminate evidence of redistribution. Tl-201 SPECT imaging may be useful in defining the reduction in ischemia produced by cardiac drugs

  20. Single-photon emission computed tomography tracers for predicting and monitoring cancer therapy.

    Science.gov (United States)

    Cai, Jiong; Li, Fang

    2013-01-01

    Cancer is a lethal disease, and its therapy should be tailed to individual patients by functional imaging to optimize therapy strategies. Single-photon emission computed tomography (SPECT) is a quantitative functional imaging modality used by oncologists to monitor tumor response. SPECT can track therapy-induced biological and metabolic changes in tumors; such changes usually precede anatomical alterations. Assessment of treatment response using SPECT tracers may result in modifications in treatment planning and predicting the long-term outcome. These SPECT tracers can be classified into metabolism, cell surface receptor, intracellular receptor, microenvironment, and apoptosis tracers. The most widely used SPECT tracers include 201Tl-thallium chloride, 67Ga-gallium citrate, 123I/131I-sodium iodide, 99mTc-MIBI, 99mTc-MDP, and 123I/131I -MIBG. Apoptosis tracers, which can directly monitor early tumor response in cancer patients and can predict the outcome, have attracted increasing attention in the field of oncology. Annexin V-based SPECT tracers, including 99mTc-BTAP-annexin V, 99mTc-HYNIC-annexin-V, 99mTc-EC-annexin-V, 99mTc-i-annexin V, and 123I-annexin V, have been evaluated in clinical trials. Novel SPECT tracers, such as radiolabeled small molecules, aptamers, peptides, and proteins, need to be explored in the future to further improve the outcome of cancer therapy. In this review, SPECT tracers used to predict and monitor cancer therapy in both preclinical and clinical settings are summarized. Some tracers may contribute to the improvement of cancer therapy management. PMID:24372237

  1. Dipyridamole and exercise SPET provide different estimates of myocardial ischaemic areas: role of the severity of coronary stenoses and of the increase in heart rate during exercise

    International Nuclear Information System (INIS)

    In patients unable to perform a maximal exercise test, dipyridamole single-photon emission tomography (SPET) has a higher capacity than exercise SPET to detect coronary artery disease (CAD). However, in patients with myocardial ischaemia who are able to perform a maximal exercise test, it is not known whether these two tests may be equally used to assess the areas of myocardial ischaemia. This study was aimed at comparing the results provided by dipyridamole and exercise SPET in CAD patients with documented exercise myocardial ischaemia. Forty CAD patients who had undergone exercise thallium-201 SPET and who had myocardial ischaemia documented by an unequivocally positive exercise test underwent an additional 201Tl SPET study after dipyridamole infusion and low-level (40 W) exercise. The extent of defects was compared between the two tests and predictors of discrepant results were sought among data from exercise testing and coronary angiography. The extent of SPET defects was equivalent between the two tests in only 11 patients (28%), larger defects being observed with exercise in 18 [average difference: 12%±5% of left ventricle (LV)] and with dipyridamole in 11 (average difference: 15%±11% of LV). The best independent predictors of discrepancies between the two tests were: (1) increase in heart rate at exercise SPET, with defects being smaller at exercise than after dipyridamole in none of the patients with an increase >60 bpm (0/14), but in 42% of the oease >60 bpm (0/14), but in 42% of the others (11/26; P=0.004); and (2) an ischaemic territory related to a <70% coronary stenosis, for which SPET defects were always induced at exercise (10/10) but in only 30% (3/10) with dipyridamole (P=0.0004). Exercise and dipyridamole SPET provide different estimates of myocardial ischaemic areas. Dipyridamole allows the unmasking of perfusion abnormalities in patients who have low increases in heart rate at exercise SPET. However, dipyridamole is also much less efficient at inducing perfusion abnormalities in the ischaemic areas supplied by coronary stenoses of intermediate severity at rest angiography. (orig.)

  2. Clinical effectiveness of 99mTc-MIBI in the evaluation of bone metastasis from primary lung cancer-comparative study with 201Tl

    International Nuclear Information System (INIS)

    We compared the diagnostic usefulness of 99m Tc-MIBI (MIBI) in detection of bone metastasis from lung cancer with 201Tl (Tl). The study group was composed of 36 primary lung cancer patients. Dual isotope scintigraphy was performed after intravenous infection of 600 MBq of MIBI and 111 MBq of Tl and visual analysis was made on the basis of the scintigraphic images. In the regional evaluation, spinal bone metastases were well visualized on MIBI scintigraphy (70%) while Tl detection was only 46%. In other regions, positive rates were under 30% with both radiopharmaceuticals. The positive rate was higher in MIBI than Tl (40.1% versus 25.0%). According to X-ray findings, 71.2% of lytic metastatic lesions were detected by MIBI. In contrast 47.8% of mixed metastatic lesions could be visualized by MIBI. Only 20.6% could be detected by MIBI in the lesions with normal X ray lesions. On the comparative study of clinical parameters between the MIBI positive group and the MIBI negative group, Alkali phosphatase was significantly higher in the MIBI positive group (317.9 versus 175.2). Histopathologically all large cell carcinomas and most small cell cancer was included in the MIBI positive group. (author)

  3. Clinical effectiveness of {sup 99m}Tc-MIBI in the evaluation of bone metastasis from primary lung cancer-comparative study with {sup 201}Tl

    Energy Technology Data Exchange (ETDEWEB)

    Nagamachi, Shigeki; Jinnouchi, Seishi; Nishii, Ryuichi; Flores, L.G. II; Nakahara, Hiroshi; Futami, Shigemi; Tamura, Shozo [Miyazaki Medical Coll., Kiyotake (Japan); Kawai, Keiichi

    1999-07-01

    We compared the diagnostic usefulness of {sup 99m} Tc-MIBI (MIBI) in detection of bone metastasis from lung cancer with {sup 201}Tl (Tl). The study group was composed of 36 primary lung cancer patients. Dual isotope scintigraphy was performed after intravenous infection of 600 MBq of MIBI and 111 MBq of Tl and visual analysis was made on the basis of the scintigraphic images. In the regional evaluation, spinal bone metastases were well visualized on MIBI scintigraphy (70%) while Tl detection was only 46%. In other regions, positive rates were under 30% with both radiopharmaceuticals. The positive rate was higher in MIBI than Tl (40.1% versus 25.0%). According to X-ray findings, 71.2% of lytic metastatic lesions were detected by MIBI. In contrast 47.8% of mixed metastatic lesions could be visualized by MIBI. Only 20.6% could be detected by MIBI in the lesions with normal X ray lesions. On the comparative study of clinical parameters between the MIBI positive group and the MIBI negative group, Alkali phosphatase was significantly higher in the MIBI positive group (317.9 versus 175.2). Histopathologically all large cell carcinomas and most small cell cancer was included in the MIBI positive group. (author)

  4. Assessment of acute myocardial necrosis after cardiopulmonary resuscitation and cardioversion by means of combined thallium-201/technetium-99m pyrophosphate tomography

    International Nuclear Information System (INIS)

    Simultaneous thallium-201/technetium-99m pyrophosphate (PYP) tomography was prospectively applied to 57 patients without typical clinical or electrocardiographic signs of acute myocardial infarction within 48 h after successful resuscitation from out-of-hospital cardiac arrest. Scintigraphic evidence of acute necrosis was present in 23/57 patients (40%). Increased 99mTc-PYP uptake in the pericardial tissue was found in 24 patients (42%). Maximal creatine kinase (CK) concentration was increased in 50/57 patients (88%). CK-MB activity averaged 68 ± 52 U/l in patients with positive and 17 ± 13 U/l in patients with negative tomograms (P 201Tl/99mTc-PYP tomography. It may be concluded that simultaneous 201Tl/99mTc-PYP tomography is a valuable tool for evaluation of myocardial necrosis after cardiopulmonary resuscitation including DC countershock. Acute myocardial necrosis, as indicated by scintigraphy, represents a potential trigger for the occurrence of ventricular fibrillation. Therefore, 201Tl/99mTc-PYP tomography can be recommended in order to guide further diagnostic and therapeutic interventions in patients after cardiopulmonary resuscitation in whom the underlying cause of the occurrence of ventricular fibrillation is obscure. (orig./MG)

  5. Molecules as Sources for Indistinguishable Single Photons

    CERN Document Server

    Ahtee, V; Pfab, R; Renn, A; Ikonen, E; Götzinger, S; Sandoghdar, V

    2008-01-01

    We report on the triggered generation of indistinguishable photons by solid-state single-photon sources in two separate cryogenic laser scanning microscopes. Organic fluorescent molecules were used as emitters and investigated by means of high resolution laser spectroscopy. Continuous-wave photon correlation measurements on individual molecules proved the isolation of single quantum systems. By using frequency selective pulsed excitation of the molecule and efficient spectral filtering of its emission, we produced triggered Fourier-limited single photons. In a further step, local electric fields were applied to match the emission wavelengths of two different molecules via Stark effect. Identical single photons are indispensible for the realization of various quantum information processing schemes proposed. The solid-state approach presented here prepares the way towards the integration of multiple bright sources of single photons on a single chip.

  6. Sympathetic reinnervation in cardiac transplants: 123I-MIBG and 201Tl/99mTc-MIBI scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. H.; Oh, S. J.; Son, M. S.; Son, J. W.; Koh, K. K.; Choi, I. S.; Shin, E. K.; Park, K. Y. [Gachon Medical College, Gil Heart Center, Inchon (Korea, Republic of)

    1998-07-01

    Iodine-123 metaiodobenzylguanidine (123I-MIBG) is a norepinephrine (NE) analogue and taken up by myocardial sympathetic nerves. To determine whether cardiac sympathetic reinnervation occurs after orthotopic heart transplantation (TPL). We performed 24 serial or followup cardiac 123I-MIBG imaging and 201T1/99mTc-MIBI dipyridamole stress gated myocardial perfusion SPECT (g-MPS) in 15 pts(M : F =10 : 5; mean ages = 34.67{+-}12.92 yr; idiopathic: rheumatic=14:1) (10.80{+-}11.88 (1-48) mo) after TPL. 123I-MIBG imagins were performed in anterior position 15 minutes, 4 and 24 hours after i.v. injection of 148 MBq 123I MIBG. Image quantitation was based on the ratio of heart to mediastinal MIBG uptake (HMR). 12 subjects with < 13 (4.91{+-}3.67) months after TPL had no visible 123I-MIBG uptake on early 15 min imaging however, 12 subjects with 13 to 48(28.58{+-}12.77) months had visible cardiac 123I-MIBG uptake (HMR: 1.65 {+-}0.21 vs. 1.32{+-}0.26 p=0.002). Correlation was found between plasma NE concentration and HMR ( r=0.80: p<0.05). Compared to HMR on 15 min images (1.48{+-}0.28), neither four nor 24 hour delayed images (1.26{+-}0.23 vs. 1.06{+-}0.10 : p<0.05, respectively, ANOVA) showed definite delayed localization of MIBG. To dipyridamole stress, transplant hearts showed significant subnormal hemodynamic responses of HR, s-BP, d-BP, and rate pressure product (90.9{+-}14.9 to 102.2{+-}15.3, 136.5{+-}17.3 to 124.9{+-}13.3, 83.3{+-}12.5 to 74.7{+-}15.6, 123.2{+-}19.4 to 127.4{+-}21.8 p<0.05, respectively). One-year followup 123I-MIBG scintigraphy in nine pts showed increased HMR (1.50{+-}0,37 to 1.61{+-}0.15, p=ns) but couldnt reach the statistical significance. Out of nine followup patients, five showed increased HMR but four didnt. gMPS performed at post-TPL 48 months in one patient complaining vague chest pain whose HMR value 1.73 to 1.62 showed an apicoanterior wall reversible perfusion defect which confirmed as 90% distal left anterior descending artery stenosis by coronary angiography. In conclusion, partial sympathetic late reinnervation of the transplant human hearts can occur > 1 year after TPL whereas reinnervation is less likely to occur in pts with a pretransplantation diagnosis idiopathic cardiomyopathy.

  7. Stable single photon source in near infrared

    OpenAIRE

    Gaebel, T.; Popa, I.; A. Gruber; Domhan, M.; Jelezko, F.; Wrachtrup, J

    2004-01-01

    Owing to their unsurpassed photostability, defects in solids may be ideal candidates for single photon sources. Here we report on generation of single photons by optical excitation of a yet unexplored defect in diamond, the nickel-nitrogen complex (NE8) centre. The most striking feature of the defect is its emission bandwidth of 1.2 nm at room temperature. The emission wavelength of the defect is around 800 nm, which is suitable for telecom fibres. In addition, in this spect...

  8. Entangling single photons on a beamsplitter

    OpenAIRE

    Larque?, Matthieu; Beveratos, Alexios; Robert-philip, Isabelle

    2008-01-01

    We report on a scheme for the creation of time-bin entangled states out of two subsequent single photons. Both photons arrive on the same input port of a beamsplitter and the situation in which the photons leave the beamsplitter on different output ports is post-selected. We derive a full quantum mechanical analysis of such time-bin entanglement for emitters subject to uncorrelated dephasing processes and apply this model to sequential single photons emerging from a single s...

  9. Nanophotonic technologies for single-photon devices

    Science.gov (United States)

    Gerardino, A.; Francardi, M.; Gaggero, A.; Mattioli, F.; Leoni, R.; Balet, L.; Chauvin, N.; Marsili, F.; Fiore, A.

    2010-12-01

    The progress in nanofabrication has made possible the realization of optic nanodevices able to handle single photons and to exploit the quantum nature of single-photon states. In particular, quantum cryptography (or more precisely quantum key distribution, QKD) allows unconditionally secure exchange of cryptographic keys by the transmission of optical pulses each containing no more than one photon. Additionally, the coherent control of excitonic and photonic qubits is a major step forward in the field of solid-state cavity quantum electrodynamics, with potential applications in quantum computing. Here, we describe devices for realization of single photon generation and detection based on high resolution technologies and their physical properties. Particular attention will be devoted to the description of single-quantum dot sources based on photonic crystal microcavites optically and electrically driven: the electrically driven devices is an important result towards the realization of single photon source “on demand”. A new class of single photon detectors, based on superconducting nanowires, the superconducting single-photon detectors (SSPDs) are also introduced: the fabrication techniques and the design proposed to obtain large area coverage and photon number-resolving capability are described.

  10. Detection of right ventricular pressure overloading by thallium-201 myocardial scintigraphy. Results in 57 patients with chronic respiratory diseases

    International Nuclear Information System (INIS)

    The diagnostic value of thallium 201 (201Tl) myocardial imaging was studied in 57 patients with chronic respiratory diseases, most with COPD (n . 46), by comparing the results to hemodynamic findings. In healthy subjects, the right ventricle (RV) is not visualized; therefore, any recorded activity of the RV was considered as indicating RV hypertrophy due to RV pressure overloading (RVPO). RV activity was graded from 0 (no activity) to 3 (activity greater than or equal to that of the left ventricle). Patients were divided into three groups according to the level of the pulmonary artery mean pressure (PPA): PPA less than or equal to 20 mm Hg (no pulmonary arterial hypertension [PAH] ) . group 1, n . 20; PPA ranging from 21 to 30 mm Hg (mild to moderate PAH) . group 2, n . 20; PPA greater than 30 mm Hg (marked PAH) . group 3, n . 17. RV was visualized in 14 patients in group 3 (82 percent) and in 13 patients in group 2 (65 percent). For all patients with PAH (2 + 3) the sensitivity of 201Tl imaging for the diagnosis of RVPO was of 73 percent, higher than that of ECG and echocardiography (both 51 percent). The sensitivity of 201Tl, even if moderate (65 percent) was better than that of ECG (30 percent) or echo (40 percent) in patients with mild-to-moderate PAH (group 2). A high RV activity (grade 3) was observed in only three patients. The specificity of this method (obtained from results in group 1) was of 80 percent vs 89 percent for echo) was of 80 percent vs 89 percent for echo and 100 percent for ECG. These results suggest that 201Tl myocardial imaging is a rather sensitive method and could be of interest for the noninvasive diagnosis of RVPO in COPD patients

  11. Study of myocardial fatty acid metabolism of inactive sportsmen with 123-heptadecanoic acid (HDA) in the framework of complex cardiological examinations

    International Nuclear Information System (INIS)

    8 inactive sportsmen and 8 heavy physical workers with similar mean age (36 years) and mean body surface (2 m2) were analysed functionally and metabolically for myocardial hypertrophy. 123I-heptadecanoic acid (HDA) scintigraphy and kinetics were carried out with methods of Feinendegen and Dudczak and using Hungarian gamma-camera. In both groups good correlation was found between the myocardial uptake of 123I-HDA and 201Tl. Regional alterations of myocardial perfusion during ergometric load were analyzed and compared to alterations of the ECG and echo. (author)

  12. Incremental predictive value of myocardial scintigraphy with 123I-BMIPP in patients with acute myocardial infarction treated with primary percutaneous coronary intervention

    International Nuclear Information System (INIS)

    It is unclear whether 123I-labelled ?-methyl iodophenyl pentadecanoic acid (123I-BMIPP) myocardial scintigraphy adds further predictive value for future cardiac events compared with the variables obtained during cardiac catheterisation in patients with acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (PCI). We therefore investigated whether 123I-BMIPP imaging in patients with AMI treated by primary PCI was useful in predicting future cardiac events. One hundred and fifty-nine patients with AMI who were treated with primary PCI and underwent left ventriculography (LVG) on admission underwent 201Tl and 123I-BMIPP myocardial scintigraphy. Scintigrams were visually classified, and the total defect score (TDS) was calculated. Major adverse cardiac events (MACE) were defined as cardiac death including sudden death, congestive heart failure and recurrence of acute coronary syndrome. Patients were followed up for a mean of 34.5 months (12-63 months). Twenty-six patients had MACE. Kaplan-Meier analysis indicated that patients with the top 50% of 123I-BMIPP TDSs had a significantly higher rate of MACE (P=0.007). Patients with mismatch between 201Tl and 123I-BMIPP images also had significantly more MACE (P=0.02). In the prediction of MACE, the global chi-square value was 5.2 (P=0.001) based on LVEF (123I-BMIPP TDS and the mismatch improved the global chi-square value (?2=7.2) Myocardial scintigraphy using 201Tl and 123I-BMIPP predicts future cardiac events in patients with AMI treated with primary PCI, and provides additional predictive value compared with the variables obtained with cardiac catheterisation alone. (orig.)

  13. Incremental predictive value of myocardial scintigraphy with {sup 123}I-BMIPP in patients with acute myocardial infarction treated with primary percutaneous coronary intervention

    Energy Technology Data Exchange (ETDEWEB)

    Nanasato, Mamoru; Hirayama, Haruo [Nagoya Daini Red Cross Hospital, Cardiovascular Center, Nagoya (Japan); Ando, Akitada; Isobe, Satoshi; Nonokawa, Makoto; Murohara, Toyoaki [Nagoya University Graduate School of Medicine, Department of Cardiology, Nagoya (Japan); Kinoshita, Yoshimi; Nanbu, Ichiro [Nagoya Daini Red Cross Hospital, Department of Radiology, Nagoya (Japan); Yokota, Mitsuhiro [Nagoya University Graduate School of Medicine, Cardiovascular Division, Department of Clinical Pathophysiology, Nagoya (Japan)

    2004-11-01

    It is unclear whether {sup 123}I-labelled {beta}-methyl iodophenyl pentadecanoic acid ({sup 123}I-BMIPP) myocardial scintigraphy adds further predictive value for future cardiac events compared with the variables obtained during cardiac catheterisation in patients with acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (PCI). We therefore investigated whether {sup 123}I-BMIPP imaging in patients with AMI treated by primary PCI was useful in predicting future cardiac events. One hundred and fifty-nine patients with AMI who were treated with primary PCI and underwent left ventriculography (LVG) on admission underwent {sup 201}Tl and {sup 123}I-BMIPP myocardial scintigraphy. Scintigrams were visually classified, and the total defect score (TDS) was calculated. Major adverse cardiac events (MACE) were defined as cardiac death including sudden death, congestive heart failure and recurrence of acute coronary syndrome. Patients were followed up for a mean of 34.5 months (12-63 months). Twenty-six patients had MACE. Kaplan-Meier analysis indicated that patients with the top 50% of {sup 123}I-BMIPP TDSs had a significantly higher rate of MACE (P=0.007). Patients with mismatch between {sup 201}Tl and {sup 123}I-BMIPP images also had significantly more MACE (P=0.02). In the prediction of MACE, the global chi-square value was 5.2 (P=0.001) based on LVEF (<45%) and the number of diseased vessels (two or three). Adding {sup 123}I-BMIPP TDS and the mismatch improved the global chi-square value ({chi}{sup 2}=7.2) Myocardial scintigraphy using {sup 201}Tl and {sup 123}I-BMIPP predicts future cardiac events in patients with AMI treated with primary PCI, and provides additional predictive value compared with the variables obtained with cardiac catheterisation alone. (orig.)

  14. Technetium-99m tetrofosmin for parathyroid scintigraphy: a direct comparison with 99mTc-MIBI, 201Tl, MRI and US

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the efficacy and role of technetium-99m tetrofosmin for the detection of abnormal parathyroid glands to be referred for surgical treatment. Twenty-eight consecutive patients, including 25 primary and 3 secondary cases of hyperparathyroidism, were evaluated. 99mTc-tetrofosmin/99mTc-pertechnetate subtraction scintigraphy (TF/Tc) was performed on all patients, and the results were directly compared with those of 99mTc-methoxyisobutylisonitrile (MIBI)/99mTc-pertechnetate subtraction scintigraphy (MIBI/Tc), 201Tl/99mTc-pertechnetate subtraction scintigraphy (Tl/Tc), magnetic resonance imaging (MRI) and ultrasonography (US). In cases of single-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 63.2%, 68.4%, 57.9%, 55.6% and 63.2%, respectively. In cases of multi-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 41.7%, 41.7%, 37.5%, 58.3% and 54.2%, respectively. In cases of parathyroid adenoma, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 68.8%, 75.0%, 68.8%, 62.5% and 75.0%, respectively. In cases of parathyroid hyperplasia, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 40.7%, 40.7%, 33.3%, 53.8% and 48.1%, respectively. It is concluded that, for the detection of abnormal parathyroid glands, 99mTc-tetrofosmin is as useful as 99mTc-MIBI and is more useful than 201201Tl. (orig.)

  15. Coherent Perfect Absorption of Single Photons

    CERN Document Server

    Huang, Sumei

    2014-01-01

    We examine the question of coherent perfect absorption (CPA) of single photons, and more generally, of the quantum fields. We show the CPA of path entangled single photons in a Fabry-Perot interferometer containing an absorptive medium. The frequency of perfect absorption can be controlled by changing the interferometer parameters like the reflectivity and the complex dielectric constant of the material. We exhibit similar results for path entangled photons in micro-ring resonators. For entangled fields like the ones produced by a down converter the CPA aspect is evident in phase sensitive detection schemes such as in measurements of the squeezing spectrum.

  16. Interfacing Collective Atomic Excitations and Single Photons

    International Nuclear Information System (INIS)

    We study the performance and limitations of a coherent interface between collective atomic states and single photons. A quantized spin-wave excitation of an atomic sample inside an optical resonator is prepared probabilistically, stored, and adiabatically converted on demand into a sub-Poissonian photonic excitation of the resonator mode. The measured peak single-quantum conversion efficiency of ?=0.84(11) and its dependence on various parameters are well described by a simple model of the mode geometry and multilevel atomic structure, pointing the way towards implementing high-performance stationary single-photon sources

  17. Upconversion single photon detection near 2 um

    CERN Document Server

    Shentu, Guo-Liang; Sun, Qi-Chao; Pelc, Jason S; Fejer, M M; Zhang, Qiang; Pan, Jian-Wei

    2013-01-01

    We have demonstrated upconversion detection at the single photon level in the 2 um spectral window using a pump wavelength near 1550nm, a periodically poled lithium niobate (PPLN) waveguide, and a volume Bragg grating (VBG) to reduce noise. We achieve a system photon detection efficiency of 10%, with a noise count rate of 24,500 counts per second, competitive with other 2 um single photon detection technologies. This detector has potential applications in environmental gas monitoring, life science, and classical and quantum communication.

  18. Room temperature stable single-photon source

    OpenAIRE

    Beveratos, Alexios; Kuehn, Sergei; Brouri, Rosa; Gacoin, Thierry; Poizat, Jean-Philippe; Grangier, Philippe

    2001-01-01

    We report on the realization of a stable solid state room temperature source for single photons. It is based on the fluorescence of a single nitrogen-vacancy (NV) color center in a diamond nanocrystal. Antibunching has been observed in the fluorescence light under both continuous and pulsed excitation. Our source delivers 2*10^4 single-photon pulses per second at an excitation repetition rate of 10 MHz. The number of two-photon pulses is reduced by a factor of five compared ...

  19. Stable single photon source in near infrared

    CERN Document Server

    Gaebel, T; Gruber, A; Domhan, M; Jelezko, F; Wrachtrup, J

    2004-01-01

    Owing to their unsurpassed photostability, defects in solids may be ideal candidates for single photon sources. Here we report on generation of single photons by optical excitation of a yet unexplored defect in diamond, the nickel-nitrogen complex (NE8) centre. The most striking feature of the defect is its emission bandwidth of 1.2 nm at room temperature. The emission wavelength of the defect is around 800 nm, which is suitable for telecom fibres. In addition, in this spectral region little background light from the diamond bulk material is detected. Consequently, a high contrast in antibunching measurements is achieved.

  20. Feasibility of single photon tomography with RB-82

    International Nuclear Information System (INIS)

    Rb-82 (t 1/2 = 75 sec) is a positron emitting myocardial perfusion tracer available from a long lived (t 1/2 = 25d) Sr-82 generator. The authors have imaged Rb-82 in the single photon mode using a Pho-TV gamma camera with a parallel hole rotating tungsten collimator but only one view of the heart is obtained with each Rb-82 injection. For exercise studies with Rb-82, tomographic myocardial imaging is desirable. Because of the limited availability of ECT instrumentation, the clinical utilization of this tracer will be enhanced by the development of suitable instrumentation for imaging high energy photons in standard nuclear medicine units. A 7 pinhole collimator capable of imaging high energy photons was designed for an LFOV camera. It was built with thick shielding (2 1/2'' of lead) which largely preserved the geometry of the original system designed for low energy tracers and myocardial images obtained with N-13 ammonia were previously reported. Using 4mm pinhole inserts of tungsten, Rb-82 imaging was performed at rest in 4 male subjects after injection of tracer intravenously in doses up to 60 mCi. A commercially available software program for a DEC Gamma-11 which was designed to avoid exaggeration of lesions was used to reconstruct activity imaged from 2 - 7 minutes after injection. Tomographic sections of good quality were obtained. Sequential rest and exercise studies should be feasible with this technique of tomographic myocardial imaging. The short half life of the tracer also allows detection of changing patterns during the redistribution phase with serial injections after exercise

  1. Cardiac sarcoidosis: Reversion of myocardial perfusion abnormalities by dipyridamole

    International Nuclear Information System (INIS)

    A thallium Tl 201 scan was performed on one young patient who met all of the criteria for the diagnosis sarcoidosis. A resting scan before treatment showed marked defects which were not resolved on the redistribution scan, thus leading to the diagnosis of cardiac sarcoidosis, which was also suspected from clinical signs. After dipyridamole infusion (0.142 mg/kg per minute over 4 min), his 201Tl scan was quite normal. Haemodynamic investigation showed a low coronary sinus blood flow with a low lactate extraction: these abnormalities were fully reversed by i.v. dipyridamole infusion. Afterwards, the patient was given oral dipyridamole (450 mg/day) over 4 weeks; at the end of this treatment, his resting 201Tl scan was quite normal. These results suggest that myocardial perfusion abnormalities in sarcoidosis may be reversible after pharmacological vasodilation. Thus, in order to assess cardiac sarcoidosis, a resting myocardial scan should be performed before a scan after dipyridamole infusion. These results may have clinical, pathophysiological and therapeutic implications with regard to cardiac sarcoidosis. (orig.)

  2. Single Photon Experiments and Quantum Complementarity

    OpenAIRE

    Georgiev D. D.

    2007-01-01

    Single photon experiments have been used as one of the most striking illustrations of the apparently nonclassical nature of the quantum world. In this review we examine the mathematical basis of the principle of complementarity and explain why the Englert-Greenberger duality relation is not violated in the configurations of Unruh and of Afshar.

  3. Neutrino counting in single photon experiments

    International Nuclear Information System (INIS)

    The results from single photon experiments are reviewed and combined. The 90 % CL upper limit on the number of light neutrino species is 4.6, and the 90 % CL lower limit on the mass of two degenerate scalar electrons is 68.5 GeV for massless photinos

  4. Single Photon Experiments and Quantum Complementarity

    Directory of Open Access Journals (Sweden)

    Georgiev D. D.

    2007-04-01

    Full Text Available Single photon experiments have been used as one of the most striking illustrations of the apparently nonclassical nature of the quantum world. In this review we examine the mathematical basis of the principle of complementarity and explain why the Englert-Greenberger duality relation is not violated in the configurations of Unruh and of Afshar.

  5. Interactive Screen Experiments with Single Photons

    Science.gov (United States)

    Bronner, Patrick; Strunz, Andreas; Silberhorn, Christine; Meyn, Jan-Peter

    2009-01-01

    Single photons are used for fundamental quantum physics experiments as well as for applications. Originally being a topic of advance courses, such experiments are increasingly a subject of undergraduate courses. We provide interactive screen experiments (ISE) for supporting the work in a real laboratory, and for students who do not have access to…

  6. Optimal positioning in the detection of inferior wall infarct size with myocardial perfusion scintigraphy: prone vs. supine

    Directory of Open Access Journals (Sweden)

    ?smail Do?an

    2010-12-01

    Full Text Available Objective: The prone position is commonly utilized to reduce false positive perfusion defects because this position overcomes the diaphragmatic inferior wall attenuation in single-photon emission computerized tomography (SPECT studies. We investigated whether the prone position had an important advantage over the supine position in determining the severity and extent of infarct in patients with acute inferior myocardial infarction (MI. Methods: Twenty-nine male patients (mean age 61±10 years with acute inferior MI were enrolled in the cross-sectional study. After injection of thallium-201 (201Tl under resting conditions, redistribution SPECT imaging was twicely performed in each subject, in both the supine and prone positions, consecutively. The extent and severity scores of the perfusion defects were calculated from the sum of individual segment scores. Myocardial infarction size was also evaluated using peak cardiac troponin T (cTnT levels. Wilcoxon rank and Spearman’s rank correlation tests were used for statistical analyses of data. Results: For the supine vs. prone positions, the median defect severity scores were 8 (4-13 vs. 5 (0.5-8.5 and the defect extent scores were 4 (3-5.5 vs. 3 (0.5-4.5, respectively. Both perfusion defect scores in the prone position were significantly lower than those in the supine position (p<0.001. The mean peak cTnT level during hospitalization was 7.2±3.9 ?g/l. Peak cTnT levels were correlated with all SPECT parameters. However, the correlation was greater in the prone position (defect severity: r=0.712, p<0.001 (defect extent: r=0.790, p<0.001 than in the supine position (defect severity: r=0.495, p<0.01 (defect extent: r=0.481, p<0.01. Conclusion: In patients with inferior MI, the SPECT results revealed a significant difference between the supine and prone images. The perfusion extent and severity scores of SPECT in the inferior wall with prone imaging correlates better with the peak troponin compared to the supine position. Comparative studies that use advanced imaging tools are needed to verify our present findings.

  7. Single photonics at telecom wavelengths using nanowire superconducting detectors

    CERN Document Server

    Zinoni, C; Fiore, A; Gerardino, A; Goltsman, G N; Li, L H; Lunghi, L; Marsili, F; Smirnov, K V; Vakhtomin, Y B; Vakhtomin, Yu. B.

    2006-01-01

    Single photonic applications - such as quantum key distribution - rely on the transmission of single photons, and require the ultimate sensitivity that an optical detector can achieve. Single-photon detectors must convert the energy of an optical pulse containing a single photon into a measurable electrical signal. We report on fiber-coupled superconducting single-photon detectors (SSPDs) with specifications that exceed those of avalanche photodiodes (APDs), operating at telecommunication wavelength, in sensitivity, temporal resolution and repetition frequency. The improved performance is demonstrated by measuring the intensity correlation function g(2)(t) of single-photon states at 1300nm produced by single semiconductor quantum dots (QDs).

  8. Radio-isotopic myocardial study

    International Nuclear Information System (INIS)

    The non invasive study of the myocardium with radio-isotopes is effected either with radio-elements labeling on recently infarcted myocardium, such as PYP Tc 99m, or after I.V. injection of Tl 201 extracted by normal myocardium or after I.V. injection of radio-element which study the myocardial metabolism. The fixation of PYP Tc 99m, bordering that of calcium, appears 24 hours after the onset of the myocardial infarction; then it reduces and disappears a week later; its persistency gives evidence of an evolution to ventricular anevrism. The relatively low sensitivity and specificity of this test should induce to reserve if for precise cases. 201 Tl realizes a map of the myocardial flow because this radio-isotope reflects with damping the variations of coronary flow. The scintigraphy is made either after stress test or after I.V. injection of dipyridamole, and the sensitivity and specificity of the test is better than electrocardiographic exercise stress test. The predictive value of the test for a patient highly depends of the prevalence of the coronary disease for this patient; however the results of Tl scintigraphy are far from an ideal test; quantitative or semi-quantitative analysis of the image compared to the analogical image seems to improve sensitivity for detection of coronary disease. After myocardial infarction, its best use is to detect a left anterior descending stenosis after posterior or inferior infarction. Among the possible radio-elements of myocarding the possible radio-elements of myocardial metabolism, scintigraphy with fatty acids opens interesting prospects for the study of the myocardial clearance of the radio-isotope, that reflects the global or regional myocardial metabolism

  9. Comparison between stress myocardial perfusion SPECT recorded with cadmium-zinc-telluride and Anger cameras in various study protocols

    Energy Technology Data Exchange (ETDEWEB)

    Verger, Antoine; Karcher, Gilles [CHU-Nancy, Department of Nuclear Medicine, Nancy (France); INSERM U947, Nancy (France); Nancyclotep Experimental Imaging Platform, Nancy (France); Djaballah, Wassila [CHU-Nancy, Department of Nuclear Medicine, Nancy (France); INSERM U947, Nancy (France); Fourquet, Nicolas [Clinique Pasteur, Toulouse (France); Rouzet, Francois; Le Guludec, Dominique [AP-HP, Hopital Bichat, Department of Nuclear Medicine, Paris (France); INSERM U 773 Inserm and Denis Diderot University, Paris (France); Koehl, Gregoire; Roch, Veronique [CHU-Nancy, Department of Nuclear Medicine, Nancy (France); Nancyclotep Experimental Imaging Platform, Nancy (France); Imbert, Laetitia [CHU-Nancy, Department of Nuclear Medicine, Nancy (France); Nancyclotep Experimental Imaging Platform, Nancy (France); Centre Alexis Vautrin, Department of Radiotherapy, Vandoeuvre (France); Poussier, Sylvain [INSERM U947, Nancy (France); Nancyclotep Experimental Imaging Platform, Nancy (France); Fay, Renaud [INSERM, Centre d' Investigation Clinique CIC-P 9501, Nancy (France); Marie, Pierre-Yves [CHU-Nancy, Department of Nuclear Medicine, Nancy (France); Nancyclotep Experimental Imaging Platform, Nancy (France); INSERM U961, Nancy (France); Hopital de Brabois, CHU-Nancy, Medecine Nucleaire, Vandoeuvre-les-Nancy (France)

    2013-03-15

    The results of stress myocardial perfusion SPECT could be enhanced by new cadmium-zinc-telluride (CZT) cameras, although differences compared to the results with conventional Anger cameras remain poorly known for most study protocols. This study was aimed at comparing the results of CZT and Anger SPECT according to various study protocols while taking into account the influence of obesity. The study population, which was from three different institutions equipped with identical CZT cameras, comprised 276 patients referred for study using protocols involving {sup 201}Tl (n = 120) or {sup 99m}Tc-sestamibi injected at low dose at stress ({sup 99m}Tc-Low; stress/rest 1-day protocol; n = 110) or at high dose at stress ({sup 99m}Tc-High; rest/stress 1-day or 2-day protocol; n = 46). Each Anger SPECT scan was followed by a high-speed CZT SPECT scan (2 to 4 min). Agreement rates between CZT and Anger SPECT were good irrespective of the study protocol (for abnormal SPECT, {sup 201}Tl 92 %, {sup 99m}Tc-Low 86 %, {sup 99m}Tc-High 98 %), although quality scores were much higher for CZT SPECT with all study protocols. Overall correlations were high for the extent of myocardial infarction (r = 0.80) and a little lower for ischaemic areas (r = 0.72), the latter being larger on Anger SPECT (p < 0.001). This larger extent was mainly observed in 50 obese patients who were in the {sup 201}Tl or {sup 99m}Tc-Low group and in whom stress myocardial counts were particularly low with Anger SPECT (228 {+-} 101 kcounts) and dramatically enhanced with CZT SPECT (+279 {+-} 251 %). Concordance between the results of CZT and Anger SPECT is good regardless of study protocol and especially when excluding obese patients who have low-count Anger SPECT and for whom myocardial counts are dramatically enhanced on CZT SPECT. (orig.)

  10. Persistent Sub-diaphragmatic Activity on the Myocardial Perfusion Scan with 99mTc-Sestamibi

    Directory of Open Access Journals (Sweden)

    Ramin Sadeghi

    2008-11-01

    Full Text Available "n  We present a female patient with atypical chest pain who was referred to our department for ischemia evaluation. 99mTc-MIBI myocardial perfusion scan with dipyridamole stress was performed. Sub-diaphragmatic activity in the hepatic tissue and then in the bowel loops caused severe overlap on the inferior wall even on consecutive delayed images. Dipyridamole stress was repeated for the patient with 201Tl. The study was interpretable this time without any interfering sub-diaphragmatic activity.  

  11. Tumour-like thallium-201 accumulation in brain infarcts, an unexpected finding on single-photon emission tomography

    International Nuclear Information System (INIS)

    In the present study our purpose was to investigate whether or not foci of 201Tl accumulation occur in reperfused areas with sustained morphological integrity indicated by computed tomography (CT) scans not showing hypodensity in the acute or sub-acute period. In 16 stroke patients with possible cortical embolic infarction, dual 201Tl and technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) SPET was performed in both the acute and the subacute period. 99mTc-HMPAO SPET was performed to detect reperfusion. Follow-up CT scans from the same period were also available. In five cases 99mTc-HMPAO SPET ruled out reperfusion and 201Tl SPET was also negative. In four cases 99mTc-HMPAO studies indicated reperfusion early in the acute phase (24-72 h), and comparative CT, without showing hypodensity in the acute or subacute period, also favoured the possibility of sustained metabolic activity. In these cases 201Tl SPET was negative in both the acute and the subacute period. In seven cases CT already showed necrosis in 99mTc-HMPAO hypoperfused areas in the acute period, with negative results on corresponding 201Tl SPET. Later reperfusion occurred in the subacute period (8-14 days) as indicated by 99mTc-HMPAO SPET, at which time an unexpected focal accumulation of 201Tl was detected. (orig./MG)

  12. Tunable single-photon emission from dipolaritons

    Science.gov (United States)

    Kyriienko, O.; Shelykh, I. A.; Liew, T. C. H.

    2014-09-01

    We study a system comprising of a double quantum well embedded in a micropillar optical cavity, where strong coupling between a direct exciton, an indirect exciton, and a cavity photon is achieved. We show that the resulting hybrid quasiparticles—dipolaritons—can induce strong photon correlations and lead to antibunched behavior of the cavity output field. The origin of the observed single-photon emission is attributed to unconventional photon blockade. We find that the second-order equal-time correlation function g(2)(0) can be tuned over a large range by using an electric field applied to the structure, or by changing the frequency of the pump. This allows for on-the-flight control of cavity output properties and is important for the future generation of tunable single-photon-emission sources.

  13. Tunable single photon emission from dipolaritons

    CERN Document Server

    Kyriienko, O; Liew, T C H

    2014-01-01

    We study a system comprising of a double quantum well embedded in a micropillar optical cavity, where strong coupling between a direct exciton, indirect exciton, and cavity photon is achieved. We show that the resulting hybrid quasiparticles - dipolaritons - can induce strong photon correlations and lead to anti-bunched behaviour of the cavity output field. The origin of the observed single photon emission is attributed to unconventional photon blockade. Moreover, we find that the second-order equal time correlation function $g^{(2)}(0)$ can be tuned over a large range using an electric field applied to the structure, or changing the frequency of the pump. This allows for an on-the-flight control of cavity output properties, and is important for the future generation of tunable single photon emission sources.

  14. Optimized Heralding Schemes for Single Photons

    CERN Document Server

    Huang, Yu-Ping; Kumar, Prem

    2011-01-01

    A major obstacle to a practical, heralded source of single photons is the fundamental trade-off between high heralding efficiency and high production rate. To overcome this difficulty, we propose applying sequential spectral and temporal filtering on the signal photons before they are detected for heralding. Based on a multimode theory that takes into account the effect of simultaneous multiple photon-pair emission, we find that these filters can be optimized to yield both a high heralding efficiency and a high production rate. While the optimization conditions vary depending on the underlying photon-pair spectral correlations, all correlation profiles can lead to similarly high performance levels when optimized filters are employed. This suggests that a better strategy for improving the performance of heralded single-photon sources is to adopt an appropriate measurement scheme for the signal photons, rather than tailoring the properties of the photon-pair generation medium.

  15. Evaluation of myocardial scintigraphy for the primary care of acute myocardial infarction

    International Nuclear Information System (INIS)

    We have evaluated the usefulness of myocardial scintigraphy in the primary care of patients with chest pain attack by performing the scintiscan at the earliest possible periods after attack. Materials included 16 patients with chest pain admitted through emergency room being diagnosed as AMI (12 cases) or suspected of AMI on the basis of clinical findings and conventional examinations including ECG and serum enzyme levels. Of 12 patients with AMI 11 revealed abnormal accumulation of sup(99m)Tc-PYP and focal defects in 201Tl myocardial imaging. One case gave false negative results in both studies with sup(99m)Tc-PYP and 201TlCl. Early nuclear medicine examinations in one patient with suspected AMI revealed negative result. The patient was diagnosed later as acute pericarditis. Among 3 other patients with suspected AMI 2 showed positive and one showed negative results for AMI in scintigraphies. We believe that the nuclear medicine procedures definitely contributed to the early diagnosis of AMI in 3 patients as they provided useful informations that ECG and serum enzyme did not provide. In two patients extremely useful informations would have been obtained, if scintigrams had been performed earlier. In 9 patients scintigrams supported the diagnosis made by conventional examinations. In two patients scintigraphy gave inconsistent results with those obtained by conventional procedures. Myocardial imaging should prove useful in early differential diagnd prove useful in early differential diagnosis of chest pain patients, if the opportunity to perform the procedures increases, which is extremely limited at present because of legal restriction to the use of radioisotopes at bed side. (author)

  16. Triggered single photons from a quantum dot

    OpenAIRE

    Santori, Charles; Pelton, Matthew; Solomon, Glenn; Dale, Yseulte; Yamamoto, Yoshihisa

    2000-01-01

    We demonstrate a new method for generating triggered single photons. After a laser pulse generates excitons inside of a single quantum dot, electrostatic interactions between them and the resulting spectral shifts allow a single emitted photon to be isolated. Autocorrelation measurements show a reduction of the two-photon probability to 0.12 times the value for Poisson light. Strong anti-bunching persists when the emission is saturated. The emitted photons are also polarized.

  17. Triggered single photons from a quantum dot

    CERN Document Server

    Santori, C M; Solomon, G S; Dale, Y; Yamamoto, Y; Santori, Charles; Pelton, Matthew; Solomon, Glenn; Dale, Yseulte; Yamamoto, Yoshihisa

    2001-01-01

    We demonstrate a new method for generating triggered single photons. After a laser pulse generates excitons inside of a single quantum dot, electrostatic interactions between them and the resulting spectral shifts allow a single emitted photon to be isolated. Autocorrelation measurements show a reduction of the two-photon probability to 0.12 times the value for Poisson light. Strong anti-bunching persists when the emission is saturated. The emitted photons are also polarized.

  18. Tunable single photon emission from dipolaritons

    OpenAIRE

    Kyriienko, O.; Shelykh, I. A.; Liew, T. C. H.

    2014-01-01

    We study a system comprising of a double quantum well embedded in a micropillar optical cavity, where strong coupling between a direct exciton, indirect exciton, and cavity photon is achieved. We show that the resulting hybrid quasiparticles - dipolaritons - can induce strong photon correlations and lead to anti-bunched behaviour of the cavity output field. The origin of the observed single photon emission is attributed to unconventional photon blockade. Moreover, we find th...

  19. Superconducting Nanowire Single Photon Detector on Diamond

    CERN Document Server

    Atikian, Haig A; Salim, A Jafari; Burek, Michael J; Choy, Jennifer T; Majedi, A Hamed; Loncar, Marko

    2014-01-01

    Superconducting nanowire single photon detectors (SNSPDs) are fabricated directly on diamond substrates and their optical and electrical properties are characterized. Dark count performance and photon count rates are measured at varying temperatures for 1310nm and 632nm photons. The procedure to prepare diamond substrate surfaces suitable for the deposition and patterning of thin film superconducting layers is reported. Using this approach, diamond substrates with less than 300pm RMS surface roughness are obtained.

  20. A Diamond Nanowire Single Photon Antenna

    OpenAIRE

    Babinec, Tom; Hausmann, Birgit J. M.; Khan, Mughees; Zhang, Yinan; Maze, Jero; Hemmer, Philip R.; Loncar, Marko

    2009-01-01

    The development of a robust light source that emits one photon at a time is an outstanding challenge in quantum science and technology. Here, at the transition from many to single photon optical communication systems, fully quantum mechanical effects may be utilized to achieve new capabilities, most notably perfectly secure communication via quantum cryptography. Practical implementations place stringent requirements on the device properties, including stable photon generati...

  1. Quantum Information Processing with Single Photons

    OpenAIRE

    Lim, Yuan Liang

    2005-01-01

    Photons are natural carriers of quantum information due to their ease of distribution and long lifetime. This thesis concerns various related aspects of quantum information processing with single photons. Firstly, we demonstrate N-photon entanglement generation through a generalised N X N symmetric beam splitter known as the Bell multiport. A wide variety of 4-photon entangled states as well as the N-photon W-state can be generated with an unexpected non-monotonic decreasing...

  2. Quantum Beat of Two Single Photons

    OpenAIRE

    Kuhn, Ar

    2004-01-01

    The interference of two single photons impinging on a beam splitter is measured in a time-resolved manner. Using long photons of different frequencies emitted from an atom-cavity system, a quantum beat with a visibility close to 100% is observed in the correlation between the photodetections at the output ports of the beam splitter. The time dependence of the beat amplitude reflects the coherence properties of the photons. Most remarkably, simultaneous photodetections are ne...

  3. Do single photons tunnel faster than light?

    OpenAIRE

    Winful, Herbert G.

    2007-01-01

    Experiments done in the early 1990's produced a surprising result: that single photons pass through a photonic tunnel barrier with a group velocity faster than the vacuum speed of light. Subsequent experiments with classical pulses have also revealed apparent superluminal group velocities as well as tunneling times that saturate with barrier length, a phenomenon known as the Hartman effect. In this paper we show that the measured delays are in fact cavity lifetimes as oppose...

  4. Angle sensitive single photon avalanche diode

    Science.gov (United States)

    Lee, Changhyuk; Johnson, Ben; Molnar, Alyosha

    2015-06-01

    An ideal light sensor would provide exact information on intensity, timing, location, and angle of incoming photons. Single photon avalanche diodes (SPADs) provide such desired high (single photon) sensitivity with precise time information and can be implemented at a pixel-scale to form an array to extract spatial information. Furthermore, recent work has demonstrated photodiode-based structures (combined with micro-lenses or diffraction gratings) that are capable of encoding both spatial and angular information of incident light. In this letter, we describe the implementation of such a grating structure on SPADs to realize a pixel-scale angle-sensitive single photon avalanche diode (A-SPAD) built in a standard CMOS process. While the underlying SPAD structure provides high sensitivity, the time information of the two layers of diffraction gratings above offers angle-sensitivity. Such a unique combination of SPAD and diffraction gratings expands the sensing dimensions to pave a path towards lens-less 3-D imaging and light-field time-of-flight imaging.

  5. Iodine 125-phenylpentadecanoic acid and its beta-methyl substitute metabolism in cultured mouse embryonal myocytes; Iodine-labelled fatty acids as tracers of myocardial high energy phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Mitsuji; Ohsuzu, Fumitaka; Sakata, Nobuhiro; Katsushika, Shuuichi; Nakamura, Haruo (National Defense Medical Coll., Tokorozawa, Saitama (Japan)); Ishida, Hideyuki; Aosaki, Noboru

    1993-02-01

    Iodine-labelled fatty acids have been proposed as new tracers of cardiac metabolisms. However, it is not clear how these tracers would reflect the intracellular metabolism. Therefore, we measured the uptake and release of iodine 125-labelled phenylpentadecanoic acid (IPPA), its [beta]-methyl substitute (BMIPP) and [sup 201]Tl in cultured myocytes of mouse embryos, and compared these values to intracellular adenosine triphosphate (ATP) content after metabolic inhibitions of oxidative phosphorylation by sodium cyanide (CN), glycolysis by 2-deoxyglucose (2-DG) or fatty acid [beta]-oxidation by lactate. The uptake and release of BMIPP was not changed by any inhibitors suggesting BMIPP would not be metabolized in the myocytes. The uptake of IPPA was significantly reduced by 2DG and 60-80% of IPPA was metabolized to hydrophilic catabolites. The correlation of BMIPP and IPPA uptake to intracellular ATP content were high (r=0.89, p<0.05; r=0.86, p<0.1), but there was poor correlation of [sup 201]Tl to ATP values (r=0.53, n.s.). These results suggested that iodine-labelled fatty acids could be used as better tracers of myocardial metabolism than [sup 201]Tl. (author).

  6. Iodine 125-phenylpentadecanoic acid and its beta-methyl substitute metabolism in cultured mouse embryonal myocytes--iodine-labelled fatty acids as tracers of myocardial high energy phosphate.

    Science.gov (United States)

    Okano, M; Ishida, H; Ohsuzu, F; Sakata, N; Katsushika, S; Aosaki, N; Nakamura, H

    1993-02-01

    Iodine-labelled fatty acids have been proposed as new tracers of cardiac metabolisms. However, it is not clear how these tracers would reflect the intracellular metabolism. Therefore, we measured the uptake and release of iodine 125-labelled phenylpentadecanoic acid (IPPA), its beta-methyl substitute (BMIPP) and 201Tl in cultured myocytes of mouse embryos, and compared these values to intracellular adenosine triphosphate (ATP) content after metabolic inhibitions of oxidative phosphorylation by sodium cyanide (CN), glycolysis by 2-deoxyglucose (2-DG) or fatty acid beta-oxidation by lactate. The uptake and release of BMIPP was not changed by any inhibitors suggesting BMIPP would not be metabolized in the myocytes. The uptake of IPPA was significantly reduced by 2DG and 60-80% of IPPA was metabolized to hydrophilic catabolites. The correlation of BMIPP and IPPA uptake to intracellular ATP content were high (r = 0.89, p < 0.05; r = 0.86, p < 0.1), but there was poor correlation of 201Tl to ATP values (r = 0.53, n.s.). These results suggested that iodine-labelled fatty acids could be used as better tracers of myocardial metabolism than 201Tl. PMID:8450598

  7. Quantitative analysis of [sup 123]I-metaiodobenzylguanidine myocardial imaging; Assessment of its usefulness in patients with congestive heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa; Honda, Minoru (Sumitomo Hospital, Osaka (Japan))

    1994-04-01

    To investigate the usefulness of the quantitative analysis of [sup 123]I-metaiodobenzylguanidine ([sup 123]I-MIBG) myocardial uptake, we studied 9 normal subjects and 18 patients with congestive heart failure (CHF). Rest myocardial [sup 123]I-MIBG imaging was performed at 20 min and 3 hr (delayed image). Rest [sup 201]Tl imaging was obtained at 20 min. In addition to ordinary tomograms, a planar anterior image and a whole body image were supplemented in each imaging. In CHF patients fractional shortening (%FS) was calculated from echocardiography and left ventricular (LV) ejection fraction was obtained from cardiac blood pool imaging with [sup 99m]Tc at rest. We calculated H/M (heart to mediastinum count ratio) from the anterior planar image and %Uptake (percentage of cardiac uptake of the isotope to total injected dose) from the whole body image. H/M of [sup 123]I-MIBG in delayed images separated CHF patients from normal subjects (2.00[+-]0.19 vs. 2.56[+-]0.13). H/M Ratio (H/M of [sup 123]I-MIBG divided by H/M of [sup 201]Tl) in delayed image could distinguish the two groups poorly (0.72[+-]0.12 vs. 0.88[+-]0.14). %Uptake of [sup 123]I-MIBG was not different between the two groups (3.49[+-]0.60% in CHF, 3.54[+-]0.34 in normal). But %Uptake of [sup 201]Tl was greater in CHF than normal (5.96[+-]1.09 vs. 4.70[+-]0.30%). When myocardial [sup 123]I-MIBG uptake was normalized by myocardial perfusion (%Uptake of [sup 123]I-MIBG divided by %Uptake of [sup 201]Tl, Uptake Ratio), Uptake Ratio in delayed image could distinguish the two groups, like H/M (0.60[+-]0.05 in CHF, 0.75[+-]0.05 in normal). In CHF patients, H/M of [sup 123]I-MIBG did not reflect LV function and serum norepinephrine (NE) level. But Uptake Ratio and H/M Ratio in delayed image correlated well with %FS (r=0.88, r=0.65), EF (r=0.80, r=0.68) and NE level (r=-0.77, r=-0.75). The calculation of Uptake Ratio is considered useful for quantitating myocardial [sup 123]I-MIBG uptake. (J.P.N.).

  8. Hypoxia-induced alteration of tracer accumulation in cultured cancer cells and xenografts in mice: implications for pre-therapeutic prediction of treatment outcomes with 99mTc-sestamibi, 201Tl chloride and 99mTc-HL91

    International Nuclear Information System (INIS)

    Weak visualization of tumours in pre-therapeutic scintigrams with technetium-99m sestamibi (MIBI) is likely a predictive sign of unfavourable tumour response to radiotherapy and chemotherapy. However, factors relating to this scintigraphic finding are not well understood. The presence of hypoxic tumour cells is one of the major reasons for therapeutic failure; consequently, we attempted to determine whether oxygenation status affects 99mTc-MIBI accumulation in tumour cells. LS180 human colon cancer and T24 human bladder cancer cells were incubated in air or N2 gas at 37 C. Cellular uptake of 99mTc-MIBI was subsequently determined at 15, 60 and 120 min. Uptake of thallium-201 chloride was also assessed. Uptake of 99mTc-HL91 was assessed as a hypoxic marker. Accumulation of the tracers in LS180 xenografts was observed in mice treated with 5 mg/kg hydralazine and compared with that in untreated mice. pO2 in the medium and tumours was measured with O2 microelectrodes. N2 gas flow gradually reduced pO2 in the cell suspension to 1-2 mmHg in 60 min. Cellular uptake of 99mTc-MIBI in LS180 cells decreased by approximately 30% in N2 gas in comparison to that in air throughout the study. Hypoxia had a more prominent influence on 201Tl uptake, which displayed a reduction of approximately 60% in N2 gas at 120 min, than on 99mTc-MIBI uptake.min, than on 99mTc-MIBI uptake. On the other hand, N2 gas induced an increase of 170% in 99mTc-HL91 uptake at 120 min, indicating the hypoxic condition of cells. The results of in vitro assays employing the T24 cell line were similar to those obtained with the LS180 ce