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Sample records for 99m clearance curves

  1. Technetium 99m mercaptoacetyltriglycine gamma camera clearance calculations: Methodological problems

    Major sources of errors in the gamma-camera methods for the calculation of renal clearance are the accuracy of background correction for obtaining the true renal time-activity curve and the validity of the externally recorded pre-cordial activity as an estimate of the plasmatic time-activity curve. With technetium 99m mercaptoacetyltriglycine (99mTc-MAG3), because of its high protein plasma binding, one could expect minimal extravascular diffusion and hence a more accurate externally detected plasmatic curve. The high extraction rate should reduce the influence of the background, but, on the other hand, the effect of hepatobiliary excretion on the calculation of renal clearance might be significant. Our results suggest that the hepatobiliary excretion of 99mTc-MAG3 does not influence the gamma-camera renal clearance determination, even in patients with low renal function. However, the pre-cordial curve does not reflect accurately the plasmatic disappearance curve; its calibration with a single plasma sample taken at the 20th min is responsible for significant errors, probably because of an unfavourable ratio between the intravascular and extravascular activities at the 20th min. (orig.)

  2. Effect of increased surface tension and assisted ventilation on /sup 99m/Tc-DTPA clearance

    Experiments were performed to determine the effects of conventional mechanical ventilation (CMV) and high-frequency oscillation (HFO) on the clearance of technetium-99m-labeled diethylenetriamine pentaacetate (/sup 99m/Tc-DTPA) from lungs with altered surface tension properties. A submicronic aerosol of /sup 99m/Tc-DTPA was insufflated into the lungs of anesthetized, tracheotomized rabbits before and 1 h after the administration of the aerosolized detergent dioctyl sodium sulfosuccinate (OT). Rabbits were ventilated by one of four methods: 1) spontaneous breathing; 2) CMV at 12 cmH2O mean airway pressure (MAP); 3) HFO at 12 cmH2O MAP; 4) HFO at 16 cmH2O MAP. Administration of OT resulted in decreased arterial PO2 (PaO2), increased lung wet-to-dry weight ratios, and abnormal lung pressure-volume relationships, compatible with increased surface tension. /sup 99m/Tc-DTPA clearance was accelerated after OT in all groups. The post-OT rate of clearance (k) was significantly faster (P less than 0.05) in the CMV at 12 cmH2O MAP [k = 7.57 +/- 0.71%/min (SE)] and HFO at 16 cmH2O MAP (k = 6.92 +/- 0.61%/min) groups than in the spontaneously breathing (k = 4.32 +/- 0.55%/min) and HFO at 12 cmH2O MAP (4.68 +/- 0.63%/min) groups. The clearance curves were biexponential in the former two groups. We conclude that pulmonary clearance of /sup 99m/Tc-DTPA is accelerated in high surface tension pulmonary edema, and this effect is enhanced by both conventional ventilation and HFO at high mean airway pressure

  3. Optimising technetium 99m diethylenetriaminepenta-acetate lung clearance in patients with the acquired immunodeficiency syndrome

    Pneumocystis carinii pneumonia (PCP) has become a major cause of morbidity and mortality due to infectious diseases, largely as a result of the acquired immunodeficiency syndrome (AIDS) epidemic. Since the mortality from recurrent infection is between 40% and 60%, early diagnosis and therapy are the keys to survival. The role of technetium 99m diethylenetriaminepentacetate (DTPA) aerosol pulmonary clearance was studied in 81 patients with AIDS. The mathematical technique of curve stripping was found to be the optimal method of analysis and to provide an overall sensitivity of 94% for the detection of interstitial pneumonitis. The procedure was superior to standard pathology parameters and radiography and more convenient than gallium 67 scintigraphy. (orig.)

  4. Clearance of Tc-99m DTPA aerosol from coal miners' lungs

    Alterations in regional epithelial permeability were assessed in 22 retired West Virginia coal miners' lungs by measuring the clearance of inhaled 0.5-μm Tc-99m DTPA aerosol. Activity was measured in both lungs and in regions of interest placed over the lung periphery in the apical, middle, and basal portions of each lung. Clearance rates (T/sub 1/2/) for 5 nonsmokers, 8 ex-smokers, and 9 smokers were significantly faster than for comparable subjects measured elsewhere, who were not coal miners. Regional apex-to-base distributions of DTPA were measured as a function of clearance time and compared with regional ventilation and perfusion. Regional, as well as overall lung clearance curves of 8 smokers and 4 ex-smokers had two components, with overall T/sub 1/2/ of 2. The results of our study suggest that measurement of DTPA clearance is a potentially useful noninvasive technique to assess lung injury in miners exposed to coal dust. 14 refs., 6 figs., 2 tabs

  5. Pulmonary clearance of 99mTc-DTPA aerosol in patients with progressive systemic scleroderma

    Alveolar epithelial permeability was assessed in 32 patients with progressive systemic scleroderma (PSS), using 99mTc-DTPA aerosol. Immediately after the inhalation of 99mTc-DTPA aerosol for 3 to 6 minutes under normal tidal breathing, lung was imaged sequentially for 30 minutes from the posterior by a gamma camera and exponential fitting was processed on the time activity curve. T1/2 (min) was used as a parameter for the evaluation of permeability of alveolar epithelium. Patients with collagen disease showed shorter T1/2 (T1/2=43.7±23.8 min) than the normal volunteers (T1/2=76.8±8.7 min). No significant difference was observed between patients with or without interstitial changes on the chest CT. Significant correlation was not observed between T1/2 and %VC or %DLco. In 8 cases, studies were repeated in the interval of 3 to 19 months. Improvement of T1/2 was seen in 4 cases, independent of CT findings. These results suggest that 99mTc-DTPA aerosol clearance study provides information independent from other lung examinations, and may be useful for the assessment of lung interstitial changes in patients with PSS. (author)

  6. Clearance of 99mTc-DTPA and experimentally increased alveolar surfactant content

    The authors measured clearance of 99mTc-labeled diethylenetriamine pentaacetic acid (99mTc-DTPA) in rabbits with experimentally increased alveolar surfactant content. In one group of animals, surfactant production was increased by treatment with ambroxol, and another group of animals was treated with tracheal instillation of natural surfactant. A group of untreated control animals and animals treated with instillation of saline were also studied. Clearance was measured during standard conditions of mechanical ventilation and during ventilation with large tidal volumes. In ambroxol- and surfactant-treated groups, clearance rate was reduced compared with untreated control animals. In contrast, clearance rate increased after saline instillation. The differences were observed at both modes of ventilation. The findings indicate that the pulmonary surfactant system is a rate-limiting factor for the clearance of 99mTc-DTPA and that the volume dependence of clearance is not explained by stretching of the alveolar wall only. 28 refs., 2 figs., 1 tab

  7. Dual pathway clearance of /sup 99m/Tc-DTPA from the bronchial mucosa

    Many studies have reported clearance rates of 99mTc-DTPA from the alveolar epithelial surface, but few have measured clearance of this solute from the bronchial mucosa. Those that have attempted such measurements have discounted the possibility that 99mTc-DTPA may be removed from the bronchial airways by mucocilliary transport as well as by absorption through the epithelium. This study was designed to better approximate the rate of 99mTc-DTPA absorption across the bronchial epithelium by correcting the measurements of total 99mTc-DTPA clearance for mucus transport. On two separate study days, each normal, nonsmoking subject (n = 8) breathed an aqueous aerosol (2.0 microns MMAD, sigma g = 2.0) containing 99mTc bound to DTPA or human serum ablumin (HSA) (a relatively nonpermeable solute that is cleared only by mucus transport over the period of measured clearance) while seated in front of a gamma camera. Breathing pattern was standardized to produce a similar central deposition of particles on both study days. From measurements of retention versus time over a 1-h period, exponential rate constants (Ktot and Km) were determined for the clearance of 99mTc-DTPA and 99mTc-HSA, respectively. By modeling the airways as a single compartment with two possible routes of clearance, we determined the permeability rate constant, Kp, as Ktot minus Km. Results showed that mucus clearance (Km) accounted for two thirds of the total rate of 99mTc-DTPA clearance (Ktot) (mean Ktot = 0.00985, Km = 0.00698, and Kp = 0.00287/min)

  8. Hepatic clearance of {sup 99m}Tc-GSA in cases of postoperative biliary atresia. A retrospective comparison with hepatic clearance of {sup 99m}Tc-PMT

    Yamazaki, Tetsuro; Yamada, Shogo [Tohoku Univ., Sendai (Japan). School of Medicine; Maruoka, Shin

    1998-11-01

    There are a few reports about usefulness of {sup 99m}Tc-GSA liver scintigraphy (GSA imaging) for the evaluation of postoperative state of biliary atresia. However, comparison of significance for the disease between GSA imaging and {sup 99m}Tc-PMT hepatobiliary imaging have not been reported. Fifty-six GSA imagings for 41 postoperative biliary atresia patients were reviewed and their scintigraphic findings and the functional parameters were compared with those obtained from {sup 99m}Tc-PMT hepatobiliary imaging. In quantitative analysis, although the hepatic clearance of both tracers calculated by graphical analysis (Patlak plot) were well correlated in most cases, a discrepancy was observed in several cases with jaundice. The authors conclude that the hepatic clearance of {sup 99m}Tc-GSA is a more accurate index of the hepatic reserve than that of {sup 99m}Tc-PMT which can be influenced by hyperbilirubinemia and that the combination of both examinations is helpful to evaluate development of liver injury in postoperative biliary atresia patients. (author)

  9. [Hepatic clearance of 99mTc-GSA in cases of postoperative biliary atresia--a retrospective comparison with hepatic clearance of 99mTc-PMT].

    Yamazaki, T; Maruoka, S; Yamada, S

    1998-11-01

    There are a few reports about usefulness of 99mTc-GSA liver scintigraphy (GSA imaging) for the evaluation of postoperative state of biliary atresia. However, comparison of significance for the disease between GSA imaging and 99mTc-PMT hepatobiliary imaging have not been reported. Fifty-six GSA imagings for 41 postoperative biliary atresia patients were reviewed and their scintigraphic findings and the functional parameters were compared with those obtained from 99mTc-PMT hepatobiliary imaging. In quantitative analysis, although the hepatic clearance of both tracers calculated by graphical analysis (Patlak plot) were well correlated in most cases, a discrepancy was observed in several cases with jaundice. The authors conclude that the hepatic clearance of 99mTc-GSA is a more accurate index of the hepatic reserve than that of 99mTc-PMT which can be influenced by hyperbilirubinemia and that the combination of both examinations is helpful to evaluate development of liver injury in postoperative biliary atresia patients. PMID:9916401

  10. Effect of α-naphthylisothiocyanate on blood clearance of 99mTc-phytate in dogs

    The effect of α-naphthylisothiocyanate (ANIT) on blood clearance of 99mTc-phytate (99mTc-P) in dogs was examined, and blood clearance test of 99mTc-P was compared with the cases of serum transaminase test or serum bilirubin test. Serum transaminase and bilirubin levels in dogs increased after ANIT administration, however, the degree of increase in these parameters was much lower than the cases in rats. The disappearance rate of 99mTc-P from blood in dogs decreased with the increase in dose of ANIT and with the passage of time after the ANIT administration. Changes of the blood clearance of 99mTc-P after ANIT treatment in dogs may be influenced by the disorder in the hepatocytes rather than in the bile ductule cells. The blood clearance test of 99mTc-P in dogs showed a sensitive reaction for the acute hepatic dysfunction induced by ANIT equally to the serum transaminase test or the serum bilirubin test. (author)

  11. Effect of D-galactosamine on blood clearance of 99mTc-phytate in dogs

    The effect of D-galactosamine (GalN) on the blood clearance of 99mTc-phytate (99mTc-P) in dogs was examined, and the blood clearance test of 99mTc-P was compared with the cases of the serum transaminase and bilirubin test. Serum transaminase and bilirubin levels in dogs increased dose-dependently after GalN administration, and the degree of increase in these parameters was much higher than the cases in rats. The disapearance rate of 99mTc-P from blood in dogs decreased with the increase in dose of GalN and with the passage of time after the GalN administration. Changes of the blood clearance of 99mTc-P after GalN treatment in dogs may be influenced by the disorder in the hepatocytes. The blood clearance test of 99mTc-P in dogs showed a sensitive reaction for the acute hepatic dysfunction induced by GalN equally to the serum transaminase and bilirubin test. (author)

  12. Sidestream smoke inhalation decreases respiratory clearance of 99mTc-DTPA acutely

    The permeability of the alveolar-capillary barrier to an inhaled aerosol of technetium 99m labelled diethylenetriamine penta-acetate (99mTc-DTPA is used as an index of alveolar epithelial injury. Permeability is greatly increased in active smokers. The aim of this study was to determine the effect of sidestream smoke inhalation on permeability as this has not been described previously. Lung clearance of inhaled 99mTc-DTPA aerosol was measured in 20 normal non-smoking subjects before and after exposure to one hours sidestream smoke inhalation. Measured carbon monoxide (CO) levels rose to a maximum of 23.5 ±6.2 ppm from baseline values of 0.6±1.3 (p99mTc-DTPA clearance rose from baseline 69.1± 15.6 (mean ± to 77.4 ±17.8) after smoke exposure. No effect of 99mTc-DTPA scanning of sidestream smoke was demonstrated on lung function. It was concluded that low level sidestream smoke inhalation decreases 99mTc-DTPA clearance acutely in humans. The mechanism of this unexpected result is not established but may include differences in constituents between sidestream and mainstream smoke, alterations in pulmonary microvascular blood flow, or changes in surfactant due to an acute phase irritant response. 34 refs., 2 figs

  13. Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

    We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH2O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH2O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH2O PEEP. At 2.5 cmH2O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH2O (P less than 0.05). Between 15 and 20 cmH2O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

  14. Relationship between plasma clearance and plasma protein bonding in 99mTc phosphate compounds

    Plasma clearance and plasma protein bonding of two different 99mTc pyrophosphate preparates with different content of pyrophosphate, as well as of a 99mTc diphosphonate preparate were investigated in patients who have undergone a routine scintiscanning of the skeleton. Strontium 85 was used as comparative standard for all patients. The plasma protein compound was determined by salting out the plasma proteins with a saturated ammonium sulphate solution and with a molecular filter. The overall blood activity was also determined for part of the patients. The lowest plasma protein bonding and the fastest plasma clearance was found in the diphosphonate preparate, the highest plasma protein bonding and slowest plasma clearance in the pyrophosphate preparate with the lowest pyrophosphate content. The slowest plasma clearance altogether was found in 85Sr for which the plasma protein bonding could not be measured. The conclusion in drawn that the different plasma clearance of the different 99m technetium phosphate complexes is caused by a varying protein bonding. The protein bonding is explained by the instability of the bone-seeking 99mTc phosphate complexes which at low concentrations in the plasma is converted into a non-bone-seeling 99mTc compound with high protein bonding. The different behaviour of the diphosphonate and pyrophosphate complex is traced back to a varying stability in the plasma. By adding larger amounts of pyrophosphate, the stability of 99mTc pyrophosphate in the plasma can be improved upon, this results in an improved plasma clearance and lower plasma protein bonding. (orig./MG)

  15. The effect of airway deposition on the assessment of lung injury by 99mTc-DTPA clearance

    The 99mTc-DTPA aerosol inhalation method permits detection of pulmonary epithelial damage. We investigated one of several problems, airway deposition of inhaled aerosol, on the assessment of pulmonary epithelial permeability in healthy nonsmokers and patients with interstitial lung diseases. We used the rate constant of pulmonary 99mTc-DTPA clearance curve, k, as a parameter of the epithelial permeability. The alveolar-peripheral airway deposition of aerosol was estimated by the duplicated inhalation method, which we newly developed. The mean k in patients with interstitial lung disease (2.52±0.72%/min, n=8; pc) was higher in patients with interstitial lung disease (4.08±1.63%/min; pc in both groups (pc obtained among the subjects (r=0.951; p99mTc-DTPA aerosol inhalation method although the correction was significant in the individual subjects. (author)

  16. Pulmonary clearance of 99mTc-DTPA and 99mTc-albumin in rabbits with surfactant dysfunction and lung injury

    We measured the pulmonary clearance of inhaled 99mTc-DTPA and 99mTc-albumin in rabbits with surfacant dysfunction induced by dioctyl sodium sulphosuccinate and in rabbits with lung injury induced by oleic acid. After inhalation of 99mTc-albumin in ten animals, clearance of the tracer from the lungs was monitored for 90 min. The first 30 min was a control period. Dioctyl sodium sulphosuccinate was then administered in aerosol and after another 30 min oleic acid was injected intravenously. Ten other rabbits were given 99mTc-DTPA, and clearance was externally recorded for 60 min. Five animals inhaled detergent aerosol and five animals were given oleic acid intravenously after 30 min. Airway pressures, tidal volume, and arterial blood gases were measured before and after each intervention. The half-life of 99mTc-albumin in the lung was 442 ± 123 min during the control period, 363 ± 52 min after detergent administration, and 134 ± 18 min after oleic acid administration. The half-life of 99mTc-DTPA was 94 ± 16 min before and 10 ± 0.6 min after detergent administration and 75 ± 12 min before and 18 ± 1.8 min after oleic acid administration. Gas exchange was not affected by administration of dioctyl sodium sulphosuccinate but markedly impaired after injection of oleic acid. Compliance of the respiratory system remained unaffected by detergent but decreased after injection of oleic acid. The results indicate that the rate limiting factors for the alveolo-capillary transfer of 99mTc-albumin and 99mTc-DTPA are different. Surfactant dysfunction affects the transfer of 99mTc-DTPA but not 99mTc-albumin. (author)

  17. Effects of sustained exercise on pulmonary clearance of aerosolized 99mTc-DTPA

    The effects of intensive prolonged exercise on the pulmonary clearance rate of aerosolized 99mTc-labeled diethylenetriaminepentaacetate (99mTc-DTPA) and pulmonary mechanics were studied in seven healthy nonsmoking volunteers. 99mTc-DTPA clearance and pulmonary mechanics (lung volumes and compliance) were assessed before and after 75 min of constant-load exercise performed on a treadmill, corresponding to 75% of maximal O2 uptake. Because both clearance measurements were made in similar conditions of pulmonary blood flow, respiratory rate, and tidal volume, changes in clearance rate can be assumed to represent changes of alveolar epithelial permeability. After exercise, total, apical, and basal clearance were significantly increased (P less than 0.01, 0.05, and 0.05, respectively) and the increases in total clearance and tidal volume observed during exercise were significantly correlated (P less than 0.05). In contrast, no significant change was found in pulmonary mechanics. These results show that prolonged intensive exercise induces an increase in epithelial permeability, which appears to be related to the mechanical effects of sustained increased ventilation. Because no change was evidenced in pulmonary volumes or in lung elasticity, our results suggest that this increase may result from alteration of the intercellular tight junctions rather than from a surfactant deficiency

  18. Effect of raised thoracic pressure and volume on 99mTc-DTPA clearance in humans

    Nolop, K.B.; Maxwell, D.L.; Royston, D.; Hughes, J.M.

    1986-05-01

    Although positive airway pressure is often used to treat acute pulmonary edema, the effects on epithelial solute flux are not well known. We measured independently the effect of 1) positive pressure and 2) voluntary hyperinflation on the clearance of inhaled technetium-99m-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc-DTPA) in six nonsmokers and six smokers. Lung volumes were monitored by inductance plethysmography. Each subject was studied in four situations: 1) low end-expiratory volume (LO-), 2) low volume plus 9 cmH2O continuous positive airway pressure (LO+), 3) high end-expiratory volume (HI-), and 4) high volume plus continuous positive airway pressure (HI+). The clearance half time of 99mTc-DTPA for the nonsmokers decreased from 64.8 +/- 7.0 min (mean +/- SE) at LO- to 23.2 +/- 5.3 min at HI- (P less than 0.05). Positive pressure had no synergistic effect. The mean clearance half time for the smokers was faster than nonsmokers at base line but unaffected by similar changes in thoracic volume and pressure. We conclude that, in nonsmokers, positive airway pressure increases /sup 99m/Tc-DTPA clearance primarily through an increase in lung volume and that smokers are immune to these effects.

  19. Reverse lung clearance of Tc-99m DTPA induced by postural changes

    The lung clearance of Tc 99m DTPA is generally attributed to the degree of distension of the interepithelial junctions and thus of the alveoli. To assess this hypothesis a submicronic aerosol of Tc 99m DTPA (0.5 μ mass median diameter) was inhaled by eight non smoking volunteers placed in left lateral decubitus (LLD) where the alveoli of the left lung are compressed and those of the right lung expanded. The lung radioactivity was followed with a gamma camera 15 minutes in LLD, then 15 minutes in right lateral decubitus (RLD) to reverse the relative distension of the alveoli. Regional clearances were computed on each lung divided in three horizontal slices. These results suggest that alveolar distension has a major role in the DTPA clearance which is relatively independent of the initial deposition of the aerosol

  20. Lung clearance of 99mTc-DTPA in systemic lupus erythematosus

    P.T.R. Dalcin

    2002-06-01

    Full Text Available The early demonstration of lung involvement in systemic lupus erythematosus (SLE patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min in active SLE versus 85.87 min (78.85-92.87 min in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3% when compared with SLE patients without disease activity (2 of 20 patients, 10% (P = 0.04. A significant correlation was observed between the clearance rates and cough (P<0.05, but not between the clearance rates and dyspnea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99mTc-DTPA is increased in SLE patients with active disease.

  1. Lung clearance of 99m Tc- DTPA in systemic lupus erythematous

    The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

  2. Lung clearance of {sup 99m} Tc- DTPA in systemic lupus erythematous

    Dalcin, P.T.R; Barreto, S.S.M.; Xavier, R.M.; Brenol, J.C.T. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Dept. de Medicina Interna; Cunha, R.D.; Marroni, B.J. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Hospital de Clinicas. Servico de Medicina Nuclear]. E-mail: rxavier@hcpa.ufrgs.br

    2002-06-01

    The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99 mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99 mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnoea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99 m Tc-DTPA is increased in SLE patients with active disease. (author)

  3. Distribution of cigarette smoking in the lungs and its efect upon 99mTc DTPA clearance

    The distribution of submicronic particles during cigarette smoking was demonstrated by means of an insoluble (sup(99m)Tc sulfur colloid) aerosol in eleven habitual smokers with no evidence of impaired lung function. Considerable pains were taken to simulate precisely the conditions of their usual smoking. The distribution of aerosol during smoking was compared with that during normal tidal breathing in the same subjects. All subjects showed a shift towards greater apical and central (tracheo bronchial) deposition during smoking as compared with quiet respiration. These findings may be relevant to the apical predominance of centrilobular emphysema and bronchial carcinoma. In a second study the differential clearance of a submicronic sup(99m)Tc DTPA aerosol was studied in a population of habitual smokers immediately after smoking two cigarettes and in a control population. Differential clearance was studied continuously for a period of 60 minutes at several peripheral sites in both lung fields. In non smokers the clearance curve was monoexponential over the study period. In smokers the curve was biexponential and clearance overall was more rapid than in non smokers as expected. No difference in clearance was seen between the apices and the bases in smokers to correspond to the predominent apical distribution of cigarette smoke particles in either the erect or the supine position. The biexponential clearance curve in smokers may be due to diffusion of the aerosol from both alveoli and bronchi reflecting the greater central deposition in smokers even though this may not be evident on visual inspection of the aerosol lung scan. (Author)

  4. [Evaluation on blood clearance and hepatic uptake of 99mTc-GSA in rats with blood flow conversion].

    Ohno, K

    1997-05-01

    This study was aimed to clarify a contribution of the hepatic blood flow in hepatic accumulation of 99mTc-DTPA-galactosyl serum albumin (99mTc-GSA). The experiment was performed in rats by the blood flow conversion with an external scintillation gamma camera and laser doppler flowmeter. Rats were divided into 4 groups: hepatic artery ligation (HAL, n = 10), portal vein ligation (PVL, n = 8), both hepatic artery and portal vein ligation (HAL+PVL, n = 9), and control (CONT, n = 10) groups. The scintigraphic data were obtained in each group for 10 minutes after intravenous injection of 99mTc-GSA (50 micrograms/100 g B.W). The regions of interest were assigned over the heart and whole liver and the time activity curves (TAC) were generated. Five parameters of HH 4, LHL 4, KH1, KH2, KL, were calculated as blood clearance and hepatic accumulation from TAC in each rat. HH4 as blood clearance index in CONT, HAL, PVL and HAL+PVL was 0.58 +/- 0.04 (mean +/- SE), 0.63 +/- 0.04, 0.85 +/- 0.04, 0.97 +/- 0.001, respectively. HH 4 between CONT vs PVL, HAL+PVL was statistically significant (p hepatic uptake index in CONT, HAL, PVL and HAL+PVL was 0.96 +/- 0.001, 0.93 +/- 0.01, 0.71 +/- 0.07, 0.41 +/- 0.04, respectively. This parameter was also statistically significant between CONT vs PVL and HAL+PVL groups. Another parameter of KH1 for blood clearance and KL for hepatic uptake were also significant between CONT vs PVL and HAL+PVL groups. All parameters obtained in 99mTc-GSA study correlated well with the hepatic flow rate which was measured with a laser doppler flowmeter and reflected the reduction rate of the hepatic tissue blood flow 4 minutes after the ligation of target vessels. These result suggest that blood clearance and hepatic uptake of 99mTc-GSA are significantly affected by hepatic blood inflow. 99mTc-GSA scintigraphy may be useful in evaluating hepatic tissue blood flow. PMID:9226469

  5. Effect of inspiratory resistance and PEEP on /sup 99m/Tc-DTPA clearance

    Experiments were performed to determine the effect of markedly negative pleural pressure (Ppl) or positive end-expiratory pressure (PEEP) on the pulmonary clearance (k) of technetium-99m-labeled diethylenetriaminepentaacetic acid (/sup 99m/Tc-DTPA). A submicronic aerosol containing /sup 99m/Tc-DTPA was insufflated into the lungs of anesthetized intubated sheep. In six experiments k was 0.44 +/- 0.46% (SD)/min during the initial 30 min and was unchanged during the subsequent 30-min interval [k = 0.21 +/- 12%/min] when there was markedly increased inspiratory resistance. A 3-mm-diam orifice in the inspiratory tubing created the resistance. It resulted on average in a 13-cmH2O decrease in inspiratory Ppl. In eight additional experiments sheep were exposed to 2, 10, and 15 cmH2O PEEP (20 min at each level). During 2 cmH2O PEEP k = 0.47 +/- 0.15%/min, and clearance increased slightly at 10 cmH2O PEEP [0.76 +/- 0.28%/min, P less than 0.01]. When PEEP was increased to 15 cmH2O a marked increase in clearance occurred [k = 1.95 +/- 1.08%/min, P less than 0.001]. The experiments demonstrate that markedly negative inspiratory pressures do not accelerate the clearance of /sup 99m/Tc-DTPA from normal lungs. The effect of PEEP on k is nonlinear, with large effects being seen only with very large increases in PEEP

  6. Exercise increases the lung clearance of inhaled Tc-99m DTPA

    It has been suggested that blood flow have little effect on the lung clearance of Tc-99m DTPA which depends on the alveolar distension. However an increase of pulmonary blood flow, induces a recruitment of new vascular areas which can enhance this clearance. To assess this hypothesis the pulmonary apical and basal clearances of a sumicronic aerosol of Tc-99m DTPA were studied at rest and at exercise in seven non smoking volunteers in upright posture. As a matter of fact exercising upright is known to increase primarily the apical blood flow. After inhalation the subjects were seated on a bicycle their back against a gamma camera which was linked to a computer. The lung radioactivity was registered successively during a resting and an exercising period. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise (50 Watts, 60 c. min /sup -1/, 7 min.) this regional gradient was enhanced by a large and significant increase of the apical clearances (0.0340 min /sup -1/ +-0.0063 SD versus 0.00183 min /sup -1/ +- 0.074 SD at rest, n = 7, p < 0.01). By contrast the changes of the basal clearances were slight and unsignificant (0.0146 min /sup -1/ +- 0.0062 SD versus 0.0140 min /sup -1/ +- 0.0082 SD). Since exercise induces little distension of the apical alveoli but drastically enhances the apical blood flow, the observed increase of the apical lung clearance could be primarily attributed to the recruitment of new capillaries induced by exercise in the apices. This led to an increase of the surface area permeability product

  7. The parasite clearance curve

    White NJ

    2011-01-01

    Abstract Parasite clearance rates are important measures of anti-malarial drug efficacy. They are particularly important in the assessment of artemisinin resistance. The slope of the log-linear segment in the middle of the parasite clearance curve has the least inter-individual variance and is the focus of therapeutic assessment. The factors affecting parasite clearance are reviewed. Methods of presentation and the approaches to analysis are discussed.

  8. Regional respiratory clearance of aerosolized /sup 99m/Tc-DTPA: posture and smoking effects

    We studied 10 healthy nonsmokers and 8 healthy smokers, in both the upright and supine position, to investigate whether regional differences in respiratory clearance of technetium-99m-labeled diethylenetriamine pentaacetic acid /sup 99m/Tc-DTPA (RC-DTPA) existed and to assess the influence of posture and smoking on the regional RC-DTPA. RC-DTPA was assessed by the lung clearance rates (%/min) of aerosolized /sup 99m/Tc-DTPA (0.8 micron MMD; 2.4 GSD), using data corrected for recirculating radioactivity, in the upper (zone 1), middle (zone 2), and lower (zone 3) posterior lung fields. In nonsmokers, RC-DTPA in zone 1 was faster than in zone 2 or 3 in both the upright (P less than 0.001) and supine positions (P less than 0.0). No effect was produced by changes in posture on the regional RC-DTPA. In smokers, RC-DTPA was increased in all zones compared with the nonsmokers (P = 0.004), with a further increase in RC-DTP in zone 1 in the upright posture compared with the other regions (P less than 0.001). We conclude that in nonsmokers regional RC-DTPA is faster in zone 1 than in other zones, and this is not related to recirculation of radioactivity; posture does not modify the regional RC-DTPA of nonsmokers; smoking increases RC-DTPA in all zones and more in zone 1 in the upright posture

  9. Exercise increases the lung clearance of inhaled technetium-99m DTPA

    The regional lung clearance of a deposited aerosol of [/sup 99m/Tc] diethylenetriaminepentaacetic acid was successively computed at rest and at exercise in seven nonsmoking volunteers in upright posture. The subjects were seated on a bicycle with their backs against a gamma camera. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise this regional gradient was enhanced by a large and significant increase of the apical clearances (3.40 +/- 0.63% min-1 s.d. compared with 1.82 +/- 0.75% min-1 s.d. at rest, n = 7, p less than 0.01). By contrast the changes of the basal clearances were slight and unsignificant (1.46 +/- 0.71% min-1 s.d. compared with 1.40 +/- 0.82% min-1 s.d.). This increase of the apical lung clearance could be attributed primarily to the increase of apical blood flow induced by exercise and to the subsequent increase of the permeability surface area product

  10. Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

    Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm2 body surface) in addition to normal oral fluid intake, weight-related dose of 99mTc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ''normal'' with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

  11. Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children

    Schofer, O. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Koenig, G. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bartels, U. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Bockisch, A. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Piepenburg, R. [Department of Nuclear Medicine, Johannes-Gutenberg University, Mainz (Germany); Beetz, R. [Department of Pediatrics, Johannes-Gutenberg University, Mainz (Germany); Meyer, G. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany); Hahn, K. [Department of Nuclear Medicine, Ludwig Maximilians University, Munich (Germany)

    1995-11-01

    Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm{sup 2} body surface) in addition to normal oral fluid intake, weight-related dose of {sup 99m}Tc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as ``normal`` with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (> grade I) no single kidney and no difference in split renal function > 20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months. (orig.)

  12. Clearance of aerosolized Tc-99m DTPA from normal vs. acutely smoke-injured dog lungs

    Acute cigarette smoke exposure is known to reversibly increase the clearance rate of aerosolized DTPA from human lungs. The authors studied DTPA clearance after acute severe plywood smoke exposure, on the order of that experienced by burn victims, since current diagnostic methods (Xe-133 and radiographs) for major inhalation injury are insensitive and/or non-specific. Smoke generated from burning plywood sawdust and kerosene was delivered via endotracheal tube at 370C. Skin burns were not inflicted (so the pulmonary consequences of thermal injury were not factors). Chest radiographs and Xe-133 studies were obtained before and after smoke injury but before DTPA aerosol delivery. Six normal and 7 smoke-exposed anesthetized mongrel dogs were studied with 3 mCi of Tc-99m DTPA delivered by aerosol for 5 minutes. Pulmonary Tc-99m DTPA activity was quantitated by computer. Data were acquired over the lungs at 1 frame per 10 secs. for 16 minutes, and the t/sub 1/2/ of DTPA washout from the lungs was calculated. The mean t/sub 1/2/ of 6 normal dogs was 36.52 min. (S.D. 17.73), while the t/sub 1/2/ of 7 smoke-injured dogs was 6.08 min. (S.D. 1.99). The longest t/sub 1/2/ of an injured lung (9.68 min.) was slightly more than half of the shortest t/sub 1/2/ of a normal lung (15.36 min). Thus, acutely smoke-injured dog lungs clear Tc-99m DTPA much faster than normal lungs, consistent with an increase in lung epithelial permeability. This technique may be promising clinically, since early diagnosis of inhalation injury is important for optimal therapy

  13. On the method for calculating unilateral renal clearance using 99mTc-MAG3 renal uptake ratio

    It has been reported that the renal clearance of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3), a newly developed 99mTc-labeled renal tubular agent, effectively reflects renal plasma flow and serves as a useful parameter of renal function. In this study, we investigated on the method for calculating unilateral renal clearance of 99mTc-MAG3 using renal uptake ratio (RUR) and the conversion formula between RUR and renal clearance. Renography by 99mTc-MAG3 was performed in 38 cases with various renal functions and the renal clearance was estimated by three reported methods of one-point-venous-sampling. The results by Bubeck method were most consistent with the individual clinical data. The difference in the methodology of sample measurement or the type of scintillation camera did not affect the values of RUR. The correlation between renal clearance and RUR was not significantly different among the three groups of data acquisition time for RUR, i.e., 1-2 min., 1.5-2.5 min., and 2-3 min. after tracer injection. In summary, Bubeck method and RUR between 1-3 min. after injection seems to be suitable for the establishment or the conversion formula. Using this formula unilateral renal clearance of 99mTc-MAG3 could be reliably estimated without venous sampling. (author)

  14. A camera based calculation of 99m Tc-MAG-3 clearance using conjugate views method

    Background: measurement of absolute or different renal function using radiotracers plays an important role in the clinical management of various renal diseases. Gamma camera quantitative methods is approximations of renal clearance may potentially be as accurate as plasma clearance methods. However some critical factors such as kidney depth and background counts are still troublesome in the use of this technique. In this study the conjugate-view method along with some background correction technique have been used for the measurement of renal activity in99mTc- MAG3 renography. Transmission data were used for attenuation correction and the source volume was considered for accurate background subtraction. Materials and methods: the study was performed in 35 adult patients referred to our department for conventional renography and ERPF calculation. Depending on patients weight approximately 10-15 mCi 99 Tc-MAG3 was injected in the form of a sharp bolus and 60 frames of 1 second followed by 174 frames of 10 seconds were acquired for each patient. Imaging was performed on a dual-head gamma camera(SOLUS; SunSpark10, ADAC Laboratories, Milpitas, CA) anterior and posterior views were acquired simultaneously. A LEHR collimator was used to correct the scatter for the emission and transmission images. Buijs factor was applied on background counts before background correction (Rutland-Patlak equation). gamma camera clearance was calculated using renal uptake in 1-2, 1.5-2.5, 2-3 min. The same procedure was repeated for both renograms obtained from posterior projection and conjugated views. The plasma clearance was also directly calculated by three blood samples obtained at 40, 80, 120 min after injection. Results: 99 Tc-MAG3 clearance using direct sampling method were used as reference values and compared to the results obtained from the renograms. The maximum correlation was found between conjugate view clearance at 2-3 min (R=0.99, R2=0.98, SE=15). Conventional posterior

  15. Bronchoscintigraphy and pulmonary clearance of 99mTc-albumin colloid in study of mucociliary clearance

    A radioaerosol based method for measuring MC was introduced. It included an inhalation protocol that resulted in a predominant deposition of radioaerosol in the central bronchi and two simple procedures of evaluation: 1) a visual semi-quantitative bronchoscintigraphic analysis, and 2) a quantitative analysis of the retention of the radioactivity at different points after the inhalation. The results showed that bronchoscintigraphy was a simple technique that may be used to visualize a stimulation of mucociliary transport in the central airways of individuals that do not suffer from too much mucus hypersecretion. Comparison of the MC between individuals, however, should preferably be performed by the method of quantitative analysis of the radioactivity disappearance. A change of MC was found to be one of the first detectable effects on lung function of tobacco smoking. It could be effectively detected by measurement of radioaerosol clearance both by bronchoscintigraphy and simple quantification of the MC. The MC may be either acutely enhanced, reduced or not changed by smoking. Long-term smoking impairs MC. The enhancement of MC by β2-agonists was very limited in most patients with CF. In the hope of increasing mucus transport in patients with CF, these are treated with various chest physiotherapy techniques. The radioaerosol based method of measurement of MC could assess mucus clearance by chest physiotherapy and cough. (au)

  16. Ozone-induced changes in the pulmonary clearance of (99m)Tc-DTPA in man

    Ozone is a respiratory irritant that has been shown in animals to increase the premeability of the respiratory epithelium. In the study the authors have recently reported that respiratory epithelial permeability was similarly affected in eight healthy non-smoking young men exposed to ozone (ARRD, 135 (1987) 1124-8). Permeability was evaluated by determining the pulmonary clearance of inhaled aerosolized 99mTc-DTPA with sequential posterior lung imaging by a computer-assisted gamma camera. In a randomized crossover design, 16 young men were exposed for 2 h to purified air and 0.4 ppm ozone while performing intermittent high intensity treadmill exercise; forced vital capacity (FVC) was measured before and at the end of exposures. The results demonstrate that ozone exposure increased respiratory epithelial permeability. Such an increase may be a manifestation of direct ozone-induced epithelial-cell injury, lung inflammation, or both

  17. Comparison of renal clearance of 99mTc-DTPA and inulin 131I-hippurate and PAH as well as creatinine clearance in Wistar-rats

    Averages and standard deviations of 99mTc-DTPA and 131I-hippurate slope clearance were consecutively determined for 56 male Wistar rats, with a body-weight of 271 ± 69 g in a single investigation. Clearance of 99mTc-DTPA was 17.4 ± 3.4, that of 131I-hippurate was 34.3 ± 7.2 μl · s-1 per 100 g body weight. For 17 rats inulin and PAH clearances were determined after 3 days with the steady-state method with continuous infusion and 3-4 periods of urine collection. During the same periods endogeneous creatinine clearance was determined. 99mTc-DTPA slope clearance correlated well with inulin clearance, also the hippurate with the PAH clearance. The high values of the filtration fraction, calculated from radioisotope and chemical methods, and the low PAH extraction of 42% lead to the conclusion, that PAH and hippurate are incompletely eliminated by the rat kidney from plasma and therefore are inadequate for determining renal blood flow in rats. Creatinine clearance was 4.7 ± 1.38 μl · s-1 per 100 g body weight, much lower than that of inulin and 99mTc-DTPA. Therefore is assumed, that tubular reabsorption of creatinine occurs and creatinine clearance cannot serve for the evaluation of GFR in rats. For this, however, the clearance of 99mTc-DTPA seems well applicable in Wistar rats. (author)

  18. Clearance of 99mTc-labeled albumin from lungs in anesthetized guinea pigs

    Gamma imaging was used to measure the rate of clearance of aerosolized 99mTc-human serum albumin (HSA) from the lungs of control guinea pigs and guinea pigs that received increased lung inflation or lung injury. Anesthetized guinea pigs were ventilated for 6 min with an aerosol of HSA and the radioactivity in the chest was monitored for 2 h with a gamma camera to determine whether the clearance rate would be a reliable assessment of lung epithelial permeability. Increased lung volumes were effected by application of 5 or 7 cm H2O positive end-expired pressure (5-PEEP and 7-PEEP, respectively). Lung injury was induced either by intravenous oleic acid (OA, 27-73 μl/kg) or inhalation of nitrogen dioxide (NO2, 80-100 ppm) for 2 h. Postmortem extravascular lung water volume (EVLW) provided an assessment of the degree of lung injury. Tracer clearance rates in animals receiving 5 or 7 cm H2O PEEP were not significantly different from controls (K = 0.15 ± 0.05 and 0.24 ± 0.10 vs 0.12 ± 0.03%/min, respectively, p > .05). Animals exposed to NO2 had faster tracer clearance rates (K = 0.33 ± 0.21%/min, p 2-exposed guinea pigs correlated well with injury as assessed by EVLW (r = .93, p 2O PEEP (K = 0.58 ± 0.41%/min, EVLW = 8.1 ± 0.8 mL/g dry lung tissue, p < .05), but there was no correlation between these parameters in this injury model. It is concluded that imaging of the disappearance of radiolabeled HSA in the guinea pig can be a useful index of lung epithelial permeability, but this technique is limited to certain models of lung injury. 33 refs

  19. Comparison of renal clearance of 99mTc-DTPA and inulin, 131I-hippurate and PAH as well as of the creatinine clearance in Wistar rats

    Order of magnitude and standard deviation of 99mTc-DTPA and 131I-hippurate slope clearance were analyzed successively in 56 male Wistar rats. The clearance of 99mTc-DTPA was 17.4 ± 3.43 μl · s-1 (100 g b-w)-1, of 131I-hippurate 34.3 ± 7.21 μl · s-1 (100 g b-w)-1. In 17 rats inulin and PAH clearances were analyzed by steady state method with permanent infusion and 3 to 4 urine collection periods 3 days later. The endogeneous creatinine clearance was determined within the same periods. The 99mTc-DTPA slope clearance corresponded to the inulin clearance, as well as the hippurate clearance to the PAH clearance. The high filtration fraction calculated from nuclear medicine and chemical clearance methods and the low PAH extraction (42%) let suggest that PAH and hippurate are eliminated only incompletely from plasma in rat kidney and are unsuitable for determination of renal blood supply in rats. The creatinine clearance with 4.7 ± 1.38 μl · s-1 (100 g b-w)-1 was far beneath the clearance of inulin and 99mTc-DTPA, supposing that creatinine is reabsorbed tubularly in part and the creatinine clearance can not be used for valuation of the GFR in rats. However, for this the 99mTc-DTPA clearance in Wistar rats seems to be well suited. (author)

  20. Estimation of Hepatic Function Using 99mTc-DISIDA Plasma Clearance Rate

    Various methods to determine hepatic function have been studied, and among these, calculated maximal removal rate of ICG (ICG R-max) is more accurate and sensitive index for quantification of hepatic function. But calculation of ICG R-max is time-consuming, invasive, and expensive study, and even ICG R-max 1 day study is still complicated. So we tried to evaluated of hepatic function test using 99mTc-DISIDA plasma clearance rate. The author studied 11 cases of normal control, 4 cases of acute hepatitis, 8 cases of chronic hepatitis, and 19 cases of liver cirrhosis. The results were as follows: 1. In normal control, DISIDA-K was 0.70 min-1, in liver cirrhosis 0.25 min-1, in acute hepatitis 0.46 min-1, and in chronic hepatitis 0.14min-1. The most severe depressed DISIDA-K value was observed in liver cirrhosis. 2. Comparison of DISIDA-K value to liver function indices revealed no correlation between DISIDA-K value and serum albumin, prothrombin time, total bilirubin, SGOT, and alkaline phosphatase. 3. DISIDA-K value in liver cirrhosis with complication such as ascites, splenomegaly, esophageal varices, and hepatic coma was more decreased than without complication. With the above result, calculation of DISIDA-K value was found easily available, accurate, and simple index for quantification of hepatic function.

  1. Clearance of technetium-99m-DTPA and HRCT findings in the evaluation of patients with Idiopathic Pulmonary Fibrosis

    Karkavitsas Nikolaos

    2006-02-01

    Full Text Available Abstract Background Clearance of inhaled technetium-labeled diethylenetriamine pentaacetate (99mTc-DTPA is a marker of epithelial damage and an index of lung epithelial permeability. The aim of this study was to investigate the role of 99mTc-DTPA scan in patients with Idiopathic Pulmonary Fibrosis (IPF. Our hypothesis is that the rate of pulmonary 99mTc-DTPA clearance could be associated with extent of High Resolution Computed Tomography (HRCT abnormalities, cell differential of bronchoalveolar lavage fluid (BALF and pulmonary function tests (PFTs in patients with IPF. Methods We studied prospectively 18 patients (14 male, 4 female of median age 67yr (range 55–81 with histologically proven IPF. HRCT scoring included the mean values of extent of disease. Mean values of these percentages represented the Total Interstitial Disease Score (TID. DTPA clearance was analyzed according to a dynamic study using a Venticis II radioaerosol delivery system. Results The mean (SD TID score was 36 ± 12%, 3 patients had mild, 11 moderate and 4 severe TID. Abnormal DTPA clearance half-time (t1/2 Conclusion Our data suggest that 99mTc-DTPA lung scan is not well associated with HRCT abnormalities, PFTs, and BALF cellularity in patients with IPF. Further studies in large scale of patients are needed to define the role of this technique in pulmonary fibrosis.

  2. Respiratory clearance of 99mTc-DTPA and pulmonary involvement in sarcoidosis

    To investigate the relationships between the respiratory epithelial clearance of micronic aerosolized /sup 99m/Tc-DTPA (RC-DTPA) and pulmonary function, serum angiotensin-converting enzyme (SACE), and lymphocytic alveolitis in patients with sarcoidosis, RC-DTPA was measured in 49 nonsmokers with pulmonary sarcoidosis and 38 normal nonsmokers. Pulmonary involvement was evaluated on chest roentgenograms (type O = normal, type I = hilar adenopathies, type II = hilar adenopathies associated with parenchymal shadows, type III = parenchymal shadows without adenopathy) and by pulmonary function tests. Serum angiotensin-converting enzyme was determined, and a bronchoalveolar lavage was performed for alveolar lymphocyte differential counting (Ly%). RC-DTPA was increased (greater than or equal to 1.96%/min) in 12 of 31 patients with type II or III involvement but was normal in all 18 patients with type O or I involvement (p = 0.002). Patients with increased RC-DTPA had low FVC, TLC, FEV1, and resting Pao2 (p less than 0.05); resting and exercise AaPo2 were increased (p less than 0.05), but RC-DTPA correlated negatively with FEV1 (p less than 0.01), Pao2 at rest (p less than 0.005), and DLCO (p less than 0.05) and positively with resting and exercise AaPO2 (p less than 0.01). In patients with increased RC-DTPA (42 +/- 17%), Ly% did not differ from Ly% in patients with normal RC-DTPA (34 +/- 16%). SACE was increased in patients with increased RC-DTPA (56 +/- 26 U/ml versus 38 +/- 16 U/ml; p = 0.007) and correlated positively with RC-DTPA (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

  3. The measurement of 99mTc-DTPA pulmonary clearance in normals, asymptomatic smokers and diabetic patients

    We measured pulmonary epithelial permeability by 99mTc-DTPA radioaerosol clearance in patients with diabetes and correlated with the presence of microangiopathy to understand the pathophysiology of pulmonary microangiopathy and evaluate 99mTc-DTPA radioaerosol clearance as a diagnostic test to assess pulmonary microangiopathy. We performed 99mTc-DTPA radioaerosol scan in 10 normal subjects, 10 asymptomatic smokers, 20 diabetic patients without history of smoking (10 with microangiopathy, 10 without microangiopathy). 99mTc-DTPA clearance half-time (T1/2) was calculated, then compared with the result of chest radiography and pulmonary function test. Chest radiography and pulmonary function test were normal in all subjects. There were no significant difference of clinical or laboratory characteristics between these groups except age. The diabetic patients with microangiophaty were significantly older (p1/2 of normal subjects and asymptomatic smokers were significantly different (65.2±23.7 min vs 39.6±9.8 min, p1/2 was 90.5±46.5 min and significantly delayed when compared with those of normals and asymptomatic smokers (p1/2 of diabetic patients without microangiopathy, 70.0±12.7 min, was not significantly different from those of normals or asymptomatic smokers (p>0.05). No significant correlation was found between the T1/2 and spirometric parameters including DLco, FVC, FEV1, FEV1/FVC (%) and FEF25-75% in all subjects, and between the T1/2 and duration of diabetes in diabetic patients. Eventhough the influence of age can't be excluded, delayed 99mTc-DTPA clearance half-time (T1/2) in diabetic patients with microangiopathy indicates decreased pulmonary capillary permeability as one of the pathophysiologic results of pulmonary microangiopaththy. Further studies are needed in larger number of age matched control and diabetic patients to evaluate the diagnostic efficacy

  4. Effect of ethanol on droplet size, efficiency of delivery, and clearance characteristics of technetium-99m DTPA aerosol

    With recent technical advances in aerosol technology, the study of regional ventilation using [/sup 99m/Tc]DTPA aerosol has become increasingly popular. Using a cascade impactor, the authors have assessed droplet size distribution from a newly designed nebulizer. Delivery efficiency of [/sup 99m/Tc]DTPA aerosol to normal subjects was improved 70% with a 10% concentration of ethanol in the nebulizer. Using filter paper fixed to the delivery end of the aerosol device, and varying ethanol concentrations from 0-10%, an 87% increase of deposited radioactivity is measured. The addition of ethanol did not alter clearance characteristics of [/sup 99m/Tc]DTPA from the lung nor did it affect droplet size distribution

  5. Factors affecting the estimation of pulmonary half clearance times of technetium-99m diethylene triamine pentaacetate aerosol in passive smoking

    Technetium-99m aerosol lung clearance has been used as a means to evaluate pulmonary-alveolar capillary integrity. Impairment has been demonstrated in conditions such as interstitial lung disease and by active cigarette smoking. The effects of passive smoking have not been well documented. Sixteen volunteers underwent aerosol lung clearance studies with estimation of half clearance times before and immediately following exposure to cigarette smoke. Formal lung function studies, plasma nicotine levels and ambient carbon monoxide levels within the smoke chamber were estimated on both occasions. These results were compared with paired aerosol studies performed on 20 subjects acting as controls. Aerosol clearance was performed via a commercially available system (Ultravent), charged with 1 GBq99mTc DTPA. Aerosol was inhaled for five minutes, with normal tidal breathing, followed by washout for 35 minutes. Thirty-second frames were collected into a 64 x 64 word matrix. A cine was displayed to review movement and position of the stomach. Regions of interest were drawn to allow for these. An exponential fit was applied to the period before the movement was noted. It was noted that movement during the time of data acquisition may cause altered clearance time; similarly, swallowed activity in the oesophagus and stomach may be significant. After correcting for the above, no statistically significant change in aerosol lung half clearance time was demonstrated with passive smoking. 9 refs., 9 figs

  6. Diagnostic accuracy of quantitative 99mTc-MIBI scintimammography according to ROC curve analysis

    Kim, J. H.; Lee, H. K.; Seo, J. W.; Cho, N. S.; Cha, K. H.; Lee, T. H. [Gachon Medical College, Gil Medical Center, Inchon (Korea, Republic of)

    1998-07-01

    99mTc-sestamibi scintimammography (SMM) has been shown to be a useful diagnostic test in the detection of breast cancer and the receiver operating characteristic (ROC) curve analysis provides detailed information of a diagnostic test. The purpose of this study was to evaluate the feasibility and efficacy of quantitative indices of SMM in the detection of malignant breast lesions according to ROC analysis. Prone anterior, lateral planar and supine SPECT imagings were performed on 75 female patients (mean age=43.4 yr) with breast mass (size{>=}0.8cm) after intravenous injection of 20-30 mCi 99mTc-sestamibi. 45 Malignant (Invasive ductal ca(36), Inv lobular ca(5), Inv duc + lob (1), Inv tubular ca (3)) and 30 benign (fibroadenoma (13), fib cyst(12), Fat necrosis(3), papilloma(1), paraffinoma (1)) lesions were histologically proven. Data were analyzed by creating three regions of interest (ROIs) over designated areas: lesion, normal breast and right chest wall. Lesion to normal (L/NL) and lesion to chest wall (L/CW) ratios were calculated for each patient both on the planar and SPECT. The area under the ROC curve (AUC) was calculated and compared among four semiquantitative indices and an average scintimammographic index (SMM(mean)) from arithmatic mean. ROC curve analysis revealed planar L/N, SPECT L/N and L/CW ratios provide comparable better diagnostic accuracies for detection of breast cancer than planar L/CW ratio (p<0.05), respectively. For quantitative SMM of 75 lesions, malignancy rate was 60%, and Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value and Accuracy were 0.78, 0.77, 0.84, 0.72 and 0.77, respectively. Quantitative SMM is an useful objective method for differentiating malignant from benign breast lesions.

  7. Clearance of inhaled sup(99m)Tc DTPA from regions of the lung recently affected by pulmonary embolus

    Pulmonary emboli lead to regional limitation of pulmonary artery perfusion, often without affecting distribution of ventilation. We have studied the effect of this regional reduction of pulmonary artery perfusion on the integrity of epithelium of alveoli (and possibly bronchioli). Integrity of alveolar epithelium was assessed by measuring regional rates of clearance from lung to blood of an inhaled aerosol of a small molecular weight solute, sup(99m)Tc DTPA (technetium-99m diethylene-triamine-penta-acetate). Ten patients with pulmonary emboli were studied, where the diagnosis was made from 'mismatching' seen on ventilation (V) and perfusion (Q) lung scintigraphy. Rates of clearance of DTPA in regions with normal V/Q ratios were compared with embolized regions with high V/Q ratios. Clearance rates were increased in embolized regions (V/Q ratio > 1) : 2.59 +- (SD) 0.89%. min-1, compared with normal regions (V/Q ratio -1 (p<0.01). In repeat studies in nine patients (one died), after intervals between 2 and 12 weeks, the V/Q ratio of previously embolized regions decreased towards unity in all nine patients, suggesting resolution. The differences in clearance rates for DTPA between normal and embolized regions decreased in association with this return towards normal of V/Q ratios. We surmise that reduction in pulmonary artery perfusion which occurs in pulmonary embolic disease alters the integrity of the alveolar (and possibly bronchiolar) epithelium. This effect is largely reversible, recovering with return of pulmonary artery perfusion

  8. Accurate and precise plasma clearance measurement using four 99mTc-DTPA plasma samples over 4 h

    Wanasundara, Surajith N.; Wesolowski, Michal J.; Barnfield, Mark C.; Waller, Michael L.; Murray, Anthony W.; Burniston, Maria T.; Babyn, Paul S.

    2016-01-01

    Objectives Glomerular filtration rate can be measured as the plasma clearance (CL) of a glomerular filtration rate marker despite body fluid disturbances using numerous, prolonged time samples. We desire a simplified technique without compromised accuracy and precision. Materials and methods We compared CL values derived from two plasma concentration curve area methods – (a) biexponential fitting [CL (E2)] and (b) Tikhonov adaptively regularized gamma variate fitting [CL (Tk-GV)] – for 4 versus 8 h time samplings from 412 99mTc-DTPA studies in 142 patients, mostly paediatric patients, with suspected fluid disturbances. Results CL (Tk-GV) from four samples/4 h and from nine samples/8 h, both accurately and precisely agreed with the standard, which was taken to be nine samples/8 h CL from (noncompartmental) numerical integration [CL (NI)]. The E2 method, four samples/4 h, and nine samples/8 h median CL values significantly overestimated the CL (NI) values by 4.9 and 3.8%, respectively. Conclusion Compared with the standard, CL (E2) from four samples/4 h and from nine samples/8 h proved to be the most inaccurate and imprecise method examined, and can be replaced by better methods for calculating CL. The CL (Tk-GV) can be used to reduce sampling time in half from 8 to 4 h and from nine to four samples for a precise and accurate, yet more easily tolerated and simplified test. PMID:26465802

  9. Comparison of clearance determination with 131I-hippurate (split function ERPF) and 99mTc-DMSA

    The capacity of separated kidney function, estimated by means of 131I- or 123I-hippurate clearance, was compared with the capacity results from 99mTC-DMSA scintigraphy. There was found a good correlation (0.98) of the two methods. In patients with urine congestion the frequent high capacity in hippurate clearance in comparison to DMSA-scintigraphy on the affected kidney was evident. This results needs further investigations. In cases where it is necessary to evaluate the relative separated capacity of both sides, the hippurate clearance can be substituted by combination of DMSA-scintigraphy and isotope renogram. Considering surgical consequences, it is important to carry out both methods. (orig.)

  10. Comparison of /sup 99m/Tc-DTPA and /sup 113m/In-DTPA aerosol clearances in humans. Effects of smoking, hyperinflation, and in vitro oxidation

    Nolop, K.B.; Maxwell, D.L.; Fleming, J.S.; Braude, S.; Hughes, J.M.; Royston, D.

    1987-11-01

    As an index of permeability of the alveolar epithelium, the clearance of an inhaled aerosol of /sup 99m/Tc-DTPA is increased in several disease states. However, the usefulness of the test to assess the severity of disease is limited because healthy smokers also have abnormally rapid rates of clearance. Because the stability of the /sup 99m/Tc-DTPA bond might be a contributory factor, we tested the affinity of /sup 99m/Tc for DTPA in vitro, and in groups of healthy smokers (n = 13) and nonsmokers (n = 7) we measured the clearances of /sup 99m/Tc-DTPA and /sup 113m/In-DTPA, which have a similar molecular shape and charge. In vitro, sodium hypochlorite or hydrogen peroxide released as much as 98% of free /sup 99m/Tc from the /sup 99m/Tc-DTPA complex. When incubated with human neutrophils stimulated with phorbol myristate acetate, between 4 and 7% of free /sup 99m/Tc-DTPA was released after 30 min, and 12% was released after 60 min. In vivo, the clearances of both /sup 99m/Tc-DTPA and /sup 113m/In-DTPA in the smokers (n = 13) were faster than in the nonsmokers (n = 7) (p less than 0.05). Within the smokers, the mean /sup 99m/Tc-DTPA clearance (T1/2 25 +/- 4 min) was faster than the mean /sup 113m/In-DTPA clearance (34 +/- 6 min), (p less than 0.05). For nonsmokers, the difference was smaller (T1/2 /sup 99m/Tc-DTPA, 56 +/- 6; T1/2 /sup 113m/In-DTPA, 62 +/- 6) and not significant. During hyperinflation, smokers (n = 8) and nonsmokers (n = 8) both demonstrated an increase in /sup 113m/In-DTPA clearance.

  11. Hepatic plasma clearance of 99mTc-HEPIDA as a diagnostic tool: experimentally derived equations for a simplified determination

    Determination of the plasma (ClPl) and specific hepatic clearance (ClHp) of 99mTc-HEPIDA is gaining acceptance as one of the best tests for the assessment of liver parenchyma functional capacity. A standard method utilises numerous blood samples,collected after injection of the radiopharmaceutical, plus collection of the urine if specific hepatic clearance is required. It is not always necessary to obtain values of the clearances by means of the laborious multi-sample procedure. In the paper there are presented formulas,based on experimental data, that form the basis of a simplified method for determination of ClPl and ClHp using single administration of 99mTc-HEPIDA. To arrive at the value of ClPl it is sufficient to withdraw 1 blood sample in the time range of 60 to 83 min post administration of the radio-pharmaceutical. If ClHp is required, additional collection of urine over the time from 0 to 88-100 min post injection is necessary. The values of ClPl and ClHp obtained by the simplified procedure are in full accordance with those obtained by the reference method utilising a series of blood samples, collected from 5 to 90 min post injection. The simplified method is sufficient as a procedure for screening of patients for liver parenchymal damage. (author)

  12. Myocardial accumulation and clearance of technetium-99m teboroxime at 100%, 75%, 50% and zero coronary blood flow in dogs

    Sequential changes in the regional distribution of technetium 99m Teboroxime (SQ30217) were evaluated in nine dogs with graded coronary artery stenosis, occlusion and reperfusion of either the left anterior descending or left circumflex arteries. 99mTc-Teboroxime accumulation recorded by planar imaging was compared with direcly measured coronary blood flow (Doppler) and regional myocardial perfusion (microspheres). Serial images were recorded beginning at the time of injection and continuing for the next 18 min. The data were summed from minutes 2-3, 3-6, 4-8 and 9-18 after injection for comparison with the other parameters. Myocardial clearance of Teboroxime was analysed at each level of blood flow. There was a linear relationship between the Teboroxime activity ratio (abnormal/normal) and coronary blood flow (r=0.96) and regional myocardial perfusion (r=0.99). Zones of diminished perfusion were least apparent in the summed images recorded during minutes 2-3. In later images, the lesions were well visualized. The myocardial clearance half-times at 100%, 75% and 50% flow were not significantly different, while clearance half-time at total occlusion was significantly (P<0.01) faster. In the 3-6, 4-8 and 9-18 minutes summed images, the Teboroxime activity ratio increased significantly (P<0.01) after reperfusion compared with total occlusion. (orig.)

  13. Evaluation of novel cationic {sup 99m}Tc-nitrido complexes as radiopharmaceuticals for heart imaging: improving liver clearance with crown ether groups

    Liu Shuang [School of Health Sciences, Purdue University, Lafayette, IN 47907 (United States)]. E-mail: lius@pharmacy.purdue.edu; He Zhengjie [School of Health Sciences, Purdue University, Lafayette, IN 47907 (United States); Hsieh, W.-Y. [School of Health Sciences, Purdue University, Lafayette, IN 47907 (United States); Kim, Young-Seung [School of Health Sciences, Purdue University, Lafayette, IN 47907 (United States)

    2006-04-15

    This report describes the evaluation of a series of novel cationic {sup 99m}Tc-nitrido complexes, [{sup 99m}TcN(DTC)(PNP)]{sup +} (DTC=crown ether-containing dithiocarbamates; PNP=bisphosphine), as potential radiotracers for myocardial perfusion imaging. Synthesis of cationic {sup 99m}Tc-nitrido complexes was accomplished in two steps according to literature methods. Biodistribution studies were performed in rats. Planar images of Sprague-Dawley rats administered with 15{+-}2 MBq of cationic {sup 99m}Tc radiotracer were obtained using a PhoGama large field-of-view Anger camera. Samples from both urine and feces were analyzed by a reversed-phase radio-HPLC method. Results from biodistribution studies showed that most of the cationic {sup 99m}Tc-nitrido complexes have a high initial heart uptake with a long myocardial retention. They also show a rapid clearance from the liver and lungs. Cationic complexes [{sup 99m}TcN(L2)(L6)]{sup +} and [{sup 99m}TcN(L4)(L6)]{sup +} show heart/liver ratios four to five times better than that of {sup 99m}Tc-sestamibi due to their much faster liver clearance. Their heart uptake and heart/liver ratio are comparable to that of {sup 99m}TcN-DBODC5 within the experimental error. These findings have been confirmed by the results from imaging studies. Radio-HPLC analysis of urine and feces samples indicated that there was very little metabolism of cationic {sup 99m}Tc-nitrido complexes in rats under anesthesia. The key finding of this study is that lipophilicity remains the most important factor affecting both heart uptake and target-to-background (T/B) ratios. Crown ethers are very useful functional groups to improve the liver clearance of cationic {sup 99m}Tc-nitrido complexes. It is the combination of the appropriate DTCs and bisphosphines that results in cationic {sup 99m}Tc-nitrido complexes with high heart uptake and fast clearance from the liver at the same time. The fast liver clearance of [{sup 99m}TcN(L2)(L6)]{sup +} and [{sup 99

  14. Measurement of Regional and Global Pulmonary Clearance of 99mTc-DTPA (Demethylamitriptylene-Acetate): An Index of Alveolar Epithelial Permeability

    The main purpose of this study has been introduction of a new method for alveoli-capillary permeability evaluation. Many reports pointed out to the altered transit of soluble particles through this barrier. From pathophysiological aspect the main interest is the elucidation of permeability's alteration in different pulmonary pathology. We decided to use for lung epithelial permeability measurements 99mTc-DTPA inhaled aerosols and sequential assessment of its lung clearance. The aerosols were obtained using oxygen flow nebulizers with aerosols' generators Ultra Vent (Malinkrodt) and Venticis II (CIS bio international) that enabled as to get submicron particles. Oxygen flow between 9 and 11 liters per minute was used. Optimum images were obtained with 1480 MBq of inhaled aerosols at least 2 to 3 minutes. DTPA that was used for aerosols labeling had been produced in our Department and the results were compared with DTPA provided by CIS bio international. High correlation between both agents was proven. During the whole study ex tamper prepared radiopharmaceuticals were used and quality control was done using paper chromatography method. Acquisition was done in sitting position with gamma camera interfaced to a ADAC and Scintiview. The measurements lasted for 20 minutes. Data were stored on 64x64 matrices. Regions of interest over both lungs were drown and each one was divided in three segments: apical, medial, and basal. Using computer program curves of 99mTc-DTPA lung clearance were derived. From the obtained time activity curves half-time of the global and the regional lung clearance was assessed. In the control group comprised of 32 healthy volunteers (non-smokers) we had got values, used after works as reference range. Our normal values for global clearance are: 68±5,5 min. for left whole lung, 68,1±6,5 min for right whole lung, and 49±7,7 min for apical, 66,9±8 min for middle, and 75,9±6,4 min basal regional lung clearance, and they are in keeping with the

  15. Clearance of technetium-99m-labeled DTPA in hyperthyroidism without clinical evidence of lung disease, and relation to pulmonary function

    The mechanisms of dyspnea and exercise intolerance have not been fully elucidated. We aimed to investigate the clearance rate of technetium-99m diethyltriaminepentaaceticacid (Tc-99m DTPA) from lungs in hyperthyroid patients without clinical evidence of lung disease and to explore the interactions between their Tc-99m DTPA radioaerosol lung scintigraphy, spirometric measurements, and the levels of thyroid hormones. We studied 19 hyperthyroid patients and 16 sex- and age-matched controls. Thyroid hormone levels were assessed. Spirometric lung function tests, diffusing capacity of the lung for carbon monoxide (DLCO) and the clearance rate of Tc-99m DTPA were performed in all participants. Ratio of DLCO value to the alveolar ventilation (DLCO/VA) and the means of half-time (T1/2) of Tc-99m DTPA clearance rate, which were used to evaluate alveolar-capillary membrane permeability, were calculated. There were no statistical differences between spirometric parameters (vital capacity (VC), force vital capacity (FVC), one second forced expiratory volume (FEV1)/FVC, mean forced expiratory flow during the middle of FVC (FEF 25-75)) of the two groups (p>0.05). Although the mean FEV1 level was significantly lower in the hyperthyroid patients than the control subjects (p1 was only less than 80 percent of the predicted value. No significant difference in the means of DLCO, DLCO/VA or T1/2 values of Tc-99m DTPA clearance was observed between the two groups (p>0.05). In hyperthyroid patients, there was a positive relation between DLCO/VA, DLCO/VA% and T1/2 values of Tc-99m DTPA clearance (p1/2 values of Tc-99m DTPA clearance in hyperthyroid group (p>0.05). We conclude that increased thyroid hormones have no effect on permeability of alveolar-capillary membrane in hyperthyroid patients. (author)

  16. Hepatic clearance mechanism of /sup 99m/Tc-HIDA and its effect on quantitation of hepatobiliary function concise communication

    Parameters affecting the hepatobiliary clearance of /sup 99m/Tc N(2,6-dimethylphenylcarbamoylmethyl) iminodiacetic acid (Tc-HIDA) were evaluated in dogs. Competitive clearance studies were performed with Tc-HIDA after infusion to plasma saturation levels of an anion, sodium sulfobromophthalein (BSP), and a cation, oxyphenonium. The results demonstrated that Tc-HIDA is transported through hepatocytes by a carrier-mediated organic-anion pathway. The data are consistent with an alteration of the elimination kinetics of Tc-HIDA induced by elevations in the serum bilirubin level, and it is predicted that serum bilirubin at some increased concentration will dominate the distribution and elimination kinetics of Tc-HIDA independently of hepatobiliary status. A quantitative description of liver function in terms of regional distribution and elimination rate constants will require either a pharmacokinetic model that expressly includes the effects of bilirubin from transport binding sites, or the development of new hepatobiliary agents that use a different clearance mechanism from that used by bilirubin

  17. Stability, protein binding and clearance studies of [99mTc]DTPA. Evaluation of a commercially available dry-kit

    Rehling, M

    1988-01-01

    quality of a commercial [99mTc]DTPA preparation (C.I.S., France) with reference to stability, protein binding and accuracy of the determined plasma clearance values as a measure of GFR. The stability of the preparations was studied by thin-layer chromatography, the in vitro protein binding by Sephadex...... filtration after incubation with human serum albumin and in vivo protein binding by filtration of human plasma. The accuracy of the plasma clearance values was investigated by comparison with the simultaneously measured plasma clearance of [51Cr]EDTA. There was no detectable free pertechnetate or hydrolysed...... reduced technetium in eight vials five and six hours after the preparation. The in vitro protein binding 10 (20), 120 and 300 min after the preparation of eight vials was 2.3% (0.8%), 0.2% and 0.1%, respectively. The in vivo protein binding in 12 patients 5, 90 and 180 min after the injection was 0.3%, 0...

  18. Biological effects in lymphocytes irradiated with 99mTc: determination of the curve dose-response

    Biological dosimetry estimates the absorbed dose taking into account changes in biological parameters. The most used biological indicator of an exposition to ionizing radiation is the quantification of chromosomal aberrations of lymphocytes from irradiated individuals. The curves of dose versus induced biological effects, obtained through bionalyses, are used in used in retrospective evaluations of the dose, mainly in the case of accidents. In this research, a simple model for electrons and photons transports was idealized to simulate the irradiation of lymphocytes with 99m Tc, representing a system used for irradiation of blood cells. The objective of the work was to establish a curve of dose versus frequencies of chromosomal aberrations in lymphocytes of human blood. For the irradiation of blood samples micro spheres of human serum of albumin (HSAM) market with 99m Tc were used, allowing the irradiation of blood with different administered activities of 99m Tc, making possible the study the cytogenetical effects as a function of such activities. The conditions of irradiation in vivo using HSAM spheres marked with 99m Tc were simulated with MCNP 4C (Monte Carlo N-Particle) code to obtain the dose-response curve. Soft tissue composition was employed to simulate blood tissue and the analyses of the curve of dose versus biological effect showed a linear quadratic response of the unstable chromosomal aberrations. As a result, the response of dose versus chromosomal aberrations of blood irradiation with 99m Tc was best fitted by the curve Y=(8,99 ±2,06) x 1--4 + (1,24 ±0,62) x 10-2 D + (5,67 ± 0,64) x 10-2 D2. (author)

  19. Assessment of 99mTc-DMSA renoscintigraphy and uptake compared with creatinine clearance in rats with drug-induced nephrotoxicity, 1

    For evaluation of technetium-99m dimercaptosuccinic acid (99mTc-DMSA) renal uptake as an absolute renal function, 99mTc-DMSA uptake was compared with endogenous creatinine clearance (Ccr) in gentamicin-induced nephrotoxicity. Gentamicin (40 mg/kg/day) was given subcutaneously to male Wistar rats for periods of 3, 6, 9 and 12 days. On the next day, the renoscintigraphy was performed 2 hours following intravenous injection of 99mTc-DMSA and Ccr was measured. On the 7th day, 99mTc-DMSA uptake was significantly lower in the treated rats than that in control (32.27±0.92 vs 39.84±2.24%; p99mTc-DMSA uptake was measured and the histological examination was done. On the 4th day, 99mTc-DMSA uptake was significantly lower than that on the 1st day (32.32±3.00 vs 38.91±1.95%; p99mTc-DMSA uptake reduces earlier than Ccr in gentamicin-induced nephrotoxicity and 99mTc-DMSA uptake is a reliable indicator in the evaluation of a renal function in drug-induced nephrotoxicity. (author)

  20. Prediction of two-sample 99mTc-diethylene triamine pentaacetic acid plasma clearance from single-sample method

    The objective of this study was to develop an equation to predict dual plasma sample method (DPSM) 99mTc-diethylene triamine pentaacetic acid (99mTc-DTPA) plasma clearance from single plasma sample method (SPSM), and to clarify the condition in which DPSM can be substituted by SPSM in measurement of glomerular filtration rate (GFR). Patients with chronic kidney disease (CKD) were selected. Watson modified Christensen and Groth equation was used to calculate 99mTc-DTPA plasma clearance by SPSM (sGFR). The equation recommended by the Nephrourology Committee of the Society of Nuclear Medicine was used to calculate 99mTc-DTPA plasma clearance by DPSM (tGFR) in each patient. The difference between sGFR and tGFR was expressed as percent of the average of these two methods, and tGFR was predicted from sGFR. Plasma creatinine was measured by the kinetic picrate method, and GFR estimated by abbreviated modification of diet in renal disease (MDRD) equation (aGFR) and Cockcroft-Gault equation (cGFR) were evaluated as criteria in selection of DPSM and SPSM. Three hundred and sixty-nine patients with CKD were selected (208 male and 161 female). The average age and body weight were 51.4±15.5 years and 67.2±12.5 kg, respectively. The causes of CKD were glomerular disease, renal arterial stenosis, chronic tubulointerstitial disease, and other causes or causes unknown. The average tGFR was 62.9±36.5 ml/min/1.73 m2, ranging from 1-180 ml/min/1.73 m2. sGFR was significantly correlated with tGFR (r=0.9194, p2; in contrast, then tGFR was±30 ml/min/1.73 m2, the difference was constant (-1.1%, 95% confidence interval -18.3%, 16.1%), and tGFR could be predicted from sGFR using the equation: predicted tGFR (ml/min/1.73 m2)=7 4244+0.7318 x sGFR+0.0022 x sGFR2 (n=299, r2=0.9428, p2, the diagnostic sensitivity of a cut off value of aGFR=45 ml/min/1.73 m2 was 91.8%, and recommended as a criterion in the selection of DPSM and SPSM. When GFR ≥30 ml/min/1.73 m2, tGFR can be predicted from s

  1. Evaluation of hepatic function by computer analysis of sup(99m) Tc-N-pyridoxyl-5-methyltryptophan dynamic curves

    A new analytical method was developed for sup(99m)Tc-N-pyridoxy1-5-methyltryptophan (sup(99m)Tc-PMT) dynamic curves in the heart and liver using computer. Four parameters were obtained: sup(99m)Tc-PMT disappearance rate from plasma (Kd), hepatic uptake rate (Ku), hepatic excretion rate (Ke) and peak time of hepatic uptake-excretion curve (Peak Time). These parameters were determined in 51 patients with or without liver diseases. Kd, Ku and Ke significantly decreased and Peak Time also significantly prolonged in patients with chronic hepatitis, compensated and decompensated liver cirrhosis in serial order. In patients with acute hepatitis, marked decrease of Ke was observed. A good correlation was found between these parameters and other hepatic function tests such as ALP, ChE, Albumin, γ-globulin and ICG retention test. These results suggest that parameters obtained are sensitive index for evaluating the severity of liver damage. Therefore it is considered that the computer analysis of sup(99m)Tc-PMT dynamic curves is clinically very useful as hepatic function test. (author)

  2. Comparison of 51Cr-EDTA- with 99mTc-DTPA-slope-clearance for estimation of glomerular filtration rate using the one-compartment model

    Aim of this study is to determine the relationship between 51Cr-EDTA and 99mTc-DTPA slope clearance applying the 'one-compartment model'. Methods: The 'one-compartment model' was chosen to calculate and to compare the glomerular filtration rates of 25 patients with normal and pathological creatinin values after injection of 51Cr-EDTA and 99mTc-DTPA simultaneously. Results: The two clearance values correlated well (r=0.996), and the 99mTc-DTPA clearance was systematically higher (28%). The 99mTc-DTPA was calculated and compared after taking three plasma samples. Taking two samples, only minor differences were seen and the correlation was high (r=0.992). Conclusion: The results of this study encouraged us to adopt the use of 99mTc-DTPA instead of 51Cr-EDTA in determining the glomerular filtration applying the 'one-compartment model' in slope with two plasma samples. (orig.)

  3. A single-injection, two-sample method for measuring renal 99mTc-MAG3 clearance in both children and adults

    We present a method for estimating 99mTc-MAG3 clearance from both a single injection and two blood samples that is valid for both adults and children. It was obtained by fitting a scaled two-compartment model (having only two adjustable parameters) to adult and pediatric data from multiple centers

  4. Detection of impaired renal function. Is the modern serologic marker cystatin C more accurate than the 99mTc-MAG3 clearance?

    Aim: Real function is usually determined by means of creatinine-clearance, and of serum Cystatin C, the latter with increasing frequency. The present study analyses, whether the diagnostic accuracy of 99mTc-MAG3 clearance is comparable to that of these modern serologic methods. Patients, methods: 71 consecutive adult Caucasian patients (42 female, 29 male; age 50±16 yrs., range 20-83) who were referred to a nuclear medicine department for determination of bilateral renal function with 99mTc-MAG3 were included. Following sufficient hydration, 10 ml of blood were taken for determination of Cystatin C and creatinine in serum prior to i.v. injection of the radiotracer. According to the recommendations of the National Kidney Foundation, glomerular filtration rate (GFR) was calculated form serum creatinine using either Cockcroft and Gault and Modification of Diet in Renal Disease (MDRD) study equation. These estimates of GFR served as reference. Cystatin C is a low molecular protein produced by all nuclear cells and is eliminated to 85% by glomerular filtration. Analysis of 99mTc-MAG3 clearance was performed by means of Bubeck's formula. Results: Linear regression analysis produced Pearson's correlation coefficients of r=0.68 and r=-0.69 for the comparison of either Cystatin C and 99mTc-MAG3 clearance with the Cockcroft and Gault equation. The comparison of Cystatin C and 99mTc-MAG3 clearance with MDRD study equation resulted in correlation coefficients of r=0.755 and r=-0.77. None of these differences were significant. The exclusion of renal impairment or the detection of an at least moderate renal impairment revealed again no significant differences between Cystatin C and 99mTc-MAG3 clearance. Conclusions: Cystatin C and 99mTc-MAG3 clearance are equally suited to exclude renal impairment or to detect a relevant renal impairment. Differences between both procedures are more likely a result of the applied reference method. (orig.)

  5. Biological effects in lymphocytes irradiated with {sup 99m}Tc: determination of the curve dose-response; Efeitos biologicos em linfocitos irradiados com {sup 99m}Tc: determinacao da curva dose-resposta

    Oliveira, Romero Marcilio Barros Matias de

    2002-08-01

    Biological dosimetry estimates the absorbed dose taking into account changes in biological parameters. The most used biological indicator of an exposition to ionizing radiation is the quantification of chromosomal aberrations of lymphocytes from irradiated individuals. The curves of dose versus induced biological effects, obtained through bionalyses, are used in used in retrospective evaluations of the dose, mainly in the case of accidents. In this research, a simple model for electrons and photons transports was idealized to simulate the irradiation of lymphocytes with {sup 99m} Tc, representing a system used for irradiation of blood cells. The objective of the work was to establish a curve of dose versus frequencies of chromosomal aberrations in lymphocytes of human blood. For the irradiation of blood samples micro spheres of human serum of albumin (HSAM) market with {sup 99m} Tc were used, allowing the irradiation of blood with different administered activities of {sup 99m} Tc, making possible the study the cytogenetical effects as a function of such activities. The conditions of irradiation in vivo using HSAM spheres marked with {sup 99m} Tc were simulated with MCNP 4C (Monte Carlo N-Particle) code to obtain the dose-response curve. Soft tissue composition was employed to simulate blood tissue and the analyses of the curve of dose versus biological effect showed a linear quadratic response of the unstable chromosomal aberrations. As a result, the response of dose versus chromosomal aberrations of blood irradiation with {sup 99m} Tc was best fitted by the curve Y=(8,99 {+-}2,06) x 1-{sup -4} + (1,24 {+-}0,62) x 10{sup -2} D + (5,67 {+-} 0,64) x 10{sup -2} D{sup 2}. (author)

  6. Comparison of 99mTc-MAG3 plasma clearance calculating methods [Bubeck and Russell (1996) methods] by single blood sampling

    This study was a comparison of the Bubeck and Russell (1996) methods, both of which are used to calculate 99mTc-MAG3 plasma clearance by single blood sampling in consideration of the distribution volume of patients. Quadratic polynominal approximation showed a strong correlation between the plasma clearance values obtained by the two methods. The quantitative values obtained by the Bubeck method tended to be lower than those obtained by the Russell (1996) method in the high clearance range. However, in the low to medium clearance range (below 250 ml/min/1.73 m2), there was almost no difference between the values, and the relationship between the values obtained by the two methods could be expressed by a straight regression line. A comparison of plasma clearance values according to difference in blood sampling time (35 min and 44 min sampling) in adults showed that there was no significant change in clearance regardless of the state of renal function. Correlation of the renal uptake rate obtained by the Bubeck method using a gamma camera could be expressed by a good straight regression line that passed around the origin of the coordinates. The results showed that, although the plasma clearance values obtained by the Bubeck method tended to be underestimated in the high clearance range compared with the values obtained by the Russell (1996) method, there was a very good correlation between the values obtained by the Bubeck method and renal uptake rate. (author)

  7. The measurement of tracheo-bronchial mucociliary clearance with 99mTc-DTPA aerosol scintigraphy and its preliminary application in COPD patients

    Mucocoiliary clearance of respiratory channels is one of the important mechanisms guarding against retention of foreign particles within the lungs. Disorders of the mucociliary transport system play a major role among non-respiratory function in causing congenital and acquired bronchial disease. Thus, objective assay of the system is essential to recognizing and understanding abnormalities. In the present paper, a simple, noninvasive, and reliable in vivo method of monitoring mucociliary clearance function is reported. 18 healthy subjects and 32 COPD patients were studied with 99mTc-DTPA aerosol scintigraphy. Monitoring was performed by visual inspection (cinescintigraphy, to observe the distribution of 99mTc-DTPA particles and the movement of radiomucous 'hot bolus') and quantitative analysis (two indexes were utilized: the first is airway clearance ratio (ACR); the second is mucociliary clearance rate (MCC), i.e. speed of advances of mucous bolus, calculated reported by Zwas). Siemens 3700 SPECT, 64 X 64 byte mode, zoom 2. Sequential images (frame/60s) were obtained for 120 minutes. The deposition pattern of 99mTc-DTPA particles in normal subjects was uniform. The deposition pattern in COPD patients demonstrated in general a centrally located distribution with major retention in the proximal airways. Four abnormal mucous transport patterns were regionally observed: stasis, regurgitation, straying and spiral or zigzag transport. Statistical analysis showed there was a significant difference of ACR between healthy subjects and COPD patients at different time points (P<0.05). The MCC in healthy subjects and COPD patients was 3.89±0.92 mm/min and 1.32±0.59 mm/min respectively. The method of assaying tracheo-bronchial mucociliary clearance reported here is simple and objective. It has not only the advantage of visual inspection and quantitative analysis, but also has a potential usefulness in studying other bronchial diseases and evaluating of therapeutic

  8. Gfr estimation using 99mTc DTPA gates method for assessment of early diabetic nephropathy - a comparison with 24-hour creatinine clearance

    To correlate Gates glomerular filtration rate (GGFR) using technetium-99m diethylene triaminepentacetic acid (99mTc DTPA) with 24-hour creatinine clearance (CRCL) and to establish relationship with duration of diabetes in patients with early diabetic nephropathy. Study Design: A cross-sectional comparative study carried out in Nuclear Medical Centre from Aug 2009 to Jan 2010 at Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan. Patients and Methods: A total of eighty three subjects were enrolled, who were divided into three groups; group 1 comprised 31 normotensive diabetics, group 2 had 37 hypertensive diabetics while group 3 had 15 normal subjects. The DTPA GFR and creatinine clearance in healthy subjects as well as diabetic patients were compared using the unpaired student's t-test. The linear association between GFR, creatinine clearance and disease duration was expressed by Pearson's correlation coefficient 'r' along with their significance levels. Results: Gates GFR showed hyperfiltration in normotensive diabetics (96.6 +- 3.3 ml/min/1.73 m/sub 2/), significantly (p<0.05) higher than controls (85.5 +- 5 ml/min/1.73 m/sub 2/), whereas hypertensive diabetics had a significantly lower (p<0.05) Gates GFR (76.8 +- 3.7) than that of controls. Significant degree of correlation existed between GGFR and CRCL in hypertensive diabetics (p<0.05, r=0.716) and controls (r=0.546). Gates GFR also showed good correlation with duration of diabetes in both diabetic groups as compared to that of CRCL. GGFR also correlated well with duration of hypertension 0.37 (0.31-0.43) as compared to CRCL 0.155 (0.15-0.16) in all groups. Conclusions: The 99mTc-DTPA clearance correlates significantly with 24-hour creatinine clearance as well as with disease duration and can provide a simple and convenient index of kidney function in patients of early diabetic nephropathy. (author)

  9. Influence of posture and positive end-tidal expiratory pressure (PEEP) on clearance of Tc99m-DTPA from the lungs

    The clearance of Tc99m-DTPA aerosols from the lung has been used to detect and quantitate alterations in the permeability of the pulmonary epithelium. Clearance of the radionuclide is accelerated by both chronic and acute injuries to the lung and by smoking. Several laboratories have reported that Tc99m-DTPA clearance from upper lobes exceeded that from lower lobes in upright subjects. To investigate this phenomenon further the authors studied subjects with simultaneous anterior and posterior cameras in upright and supine positions. In the upright position, clearance from both the anterior and posterior upper regions of interest (ROI's) exceeded the lower regions (-1.64 +- .42 S.D. vs. -0.75 +- .41, anterior, p < .05, n=6), -1.04 +- .23 vs. -0.50 +- .36, posterior. All units = %/min. This difference was not observed in the supine subjects. Clearance from the anterior chest exceeded that from the posterior chest in the supine subjects (-1.28 +- .45 vs. -0.05 +- 1.08) and a small increase in radio-activity was observed in at least one ROI of 5 of 6 subjects from the posterior camera. An increase in activity is likely to be secondary to labeling of blood pool, which would have greatest affect where pulmonary blood volume is largest. Computer processing of the entire lung without observer bias in ROI placement showed similar effects of posture over non-peripheral ROI's. Five subjects breathed on PEEP to cause airspace distention, causing clearance to double. Both dependency and airspace distention appear to influence clearance of aerosolized DTPA, the latter may occur by stretching of epithelial pores

  10. The measuring of the resorptive clearance of inhaled 99m technetium pertechnetate in normal persons and in patients with chronically obstructive bronchitis and with lung fibrosis

    On 32 patients with lung fibrosis of various genesis, chronically obstructive bronchitis and carcinomas the resorptive clearance of the lung in comparison to 12 normal persons was carried out, specifically with a 99mTc-pertechnate aerosol in an atomiser (particle diameter of < 1 μm) doing inspiring vital capacity manuveurs. Patients with chronically obstructive bronchitis and lung fibrosis showed a clearance which slowed down in the middle, carcinoma patients showed a strongly slowed resorptive clearance in the diseased areas. A comparison with spirometric data and gas exchange parameters brought merely for MMEF a weakly significant correlation. A decisive influence of the condition of the bronchial mucous membrane on the result of the resorptive clearance was ascertained. Pollutants remain with decreased clearance longer in the lung and could possibly increase a predisposition to cancer. By the measuring of the resorptive clearance it can at least be determined which people were exposed for longer times to the damaging effects of such materials. (TRV)

  11. Quantitative structure-activity relationship analysis to elucidate the clearance mechanisms of Tc-99m labeled quinolone antibiotics

    This study aims to establish molecular modeling methods for predicting the liver and kidney uptakes of Tc-99m labeled quinolone antibiotics. Some three-dimensional quantitative-activity relationships (3D-QSAR) models were developed using comparative molecular field analysis and grid-independent descriptors procedures. As a first report on 3D-QSAR modeling, the predicted liver and kidney uptakes for quinolone antibiotics were in good agreement with the experimental values. The obtained results confirm the importance of hydrophobic interactions, size and steric hindrance of antibiotic molecules in their liver uptakes, while the electrostatic interactions and hydrogen bonding ability have impressive effects on their kidney uptakes. (author)

  12. Assessment of the arterial input curve for [99mTc]-d,l-HM-PAO by rapid octanol extraction

    Andersen, A R; Friberg, H; Lassen, N A;

    1988-01-01

    The in vitro conversion of the lipophilic molecule [99mTc]-d,l-hexamethylpropyleneamine oxime [( 99mTc]-d,l-HM-PAO) to a hydrophilic form was studied in saline, plasma, and blood at 37 degrees C by paper chromatography and by octanol extraction. The octanol:saline ratio was 79.9. From this value...

  13. Evaluation of renal function in rats: Renal clearance of 99mTc-DTPA underestimates glomerular filtration rate (GFR) as compared with renal clearance of eH-inulin or 51 CR-EDTA

    The rat is the most commonly used experimental animal and frequently being used to examine the pathophysiology in renal disease. Thus, it is important to apply techniques where renal function is assessed accurately. A special challenge exists in chronic unilateral renal disease for accurate measurement of single kidney GFR (SKGFR). We therefore examined the possibility of developing a method where SK GFR is measured in rats from the plasma clearance of 99mTc-DTPA and the reno graphically determined renal split function. A detailed comparison of renal clearance (Clr) and plasma clearance (Clp) of 99mTc-DTPA with that of 51-Cr-EDTA and 3H-inulin was performed in conscious rats with permanent catheters in the carotic artery, jugular vein and the urinary bladder using the following protocols: 1) Comparison of Clr of 99mTc-DTPA with 3H-inulin using a constant infusion clearance technique with four periods (P1-P4)(n=11), 2) comparison of Clr of 99m Tc-DTPA with that of 51Cr-EDTA or 3H-inulin (n=8) 3) comparison of Clr of 51Cr-EDTA and 3H-inulin using a constant infusion clearance technique with Clp of 99mTc-DTPA using a single injection technique with plasma sampling 4 hours after injection (n=11) and 4) comparison of Clp of 51Cr-EDTA with 99mTc-DTPA using the single injection technique (n=5). The results surprisingly showed that Clr of 99mTc-DTPA consistently was significantly lower than Clr of 51Cr-EDTA (548±146 vs. 860±49 □1/min/100g (avg±std);p<0.01) and of 3H-inulin (548±146 vs. 975±135 □1/min/100g; p<0.01: Interestingly, Clr of 99mTc-DTPA was progressively reduced with time in contrast to a constant Clr of inulin (P1:693±108 vs 939±118; P2:591±94 vs 877±17, P3:594±74 vs 947±131; P4:569±78 vs 991±122). Furthermore, Clp of 99mTc-DTPA was significantly lower than Clp of 51Cr-EDTA (874±130 vs. 1092±43 □1/min/100g;p<(0.01). The average clearance ratio DTPA/EDTA using constant infusion was 0.65±0.15 and 0.80±0.15 after single injection. In

  14. Measurement of the bronchial mucociliary clearance to estimate the success of saline spring treatment using 99mTc-HSA

    Highly significant improvement in the pulmonary mucociliary clearance in the peripheral region of the lungs four weeks after saline spring treatment was found. The possibility of applying the saccharin sky-blue test for evaluating the success of saline spring treatment was examined. (author)

  15. Assessment of calibration curve in visual analysis by a scoring system using 99mTc-GSA liver scintigraphy

    With a view to improving the correlation of liver scintigraphy using 99mTc-DTPA-galactosyl human serum albumin (GSA) with hepatic function as indicated by indices such as LHL15, HH15, and laboratory data, the present study was carried out to set up a calibration curve (CC) for visual analysis. The application of 7 patterns of CC with different settings to a 1-min image (5 to 6 minutes after radiotracer injection) in 98 cases led to the preparation of 686 images whose correlation with hepatic function was examined by 15 observers via the grade classification of a five-point scoring system using visual analysis. The grade classification was as follows: grade 1 (faint cardiac blood-pool image), grade 2 (slight cardiac blood-pool image compared with liver uptake), grade 3 (almost the same appearance of cardiac blood-pool image and that of liver uptake), grade 4 (intense cardiac blood-pool image associated with possible liver uptake), and grade 5 (very slight liver uptake). The five-point scoring system could be used for CC slopes of 4.21, 4.79 and 2.79 (the above correlation was strongest for 4.21). The significance of inter-grade group differences in ICG-R15, LHL15 and heart/liver ratio was examined according to slope. With the CC slope of 4.21, a significant inter-grade group difference was observed between grades 1 and 2, grades 2 and 3, grades 3 and 4, and grades 4 and 5. In conclusion, when the value of the CC slope was 4.2, it was considered appropriate for grade classification on a five-point scoring system using visual analysis. (author)

  16. Clearance of inhaled technetium-99m-DTPA as a clinical index of pulmonary vascular disease in systemic sclerosis

    This study evaluated the utility of the clearance time of inhaled diethylenetriamine pentaacetate (DTPA) to distinguish pulmonary vascular disease from early fibrosing alveolitis (FA) in patients with systemic sclerosis (SSc) It was hypothesized that this would be preserved in patients with vascular disease compared with FA, despite similar gas-transfer deficits and matching lung volumes, because of the preservation of alveolar epithelial integrity. All patients had SSc and were categorized into a control group (C; n=9), pulmonary vascular group (VAS; n=14) or FA group (n=14) dependent on the appearance on a computed tomography (CT) scan and the transfer factor of the lung for carbon monoxide (TL,CO) (VAS and FA ≤70%, C ≥80%). All patients had a forced vital capacity (FVC) of >80%. The TL,CO (median) was similar in the VAS (57.5%) and FA (60%) groups. There was a significant difference in median DTPA clearance half-times between FA (21.25 min) and VAS (46.5 min) (p=0.014) and between FA and C (84.5 min) (p=0.0004). No difference was found between VAS and C (p=0.0778). Follow-up data from the VAS group showed no subsequent development of FA on the CT scan and no decrease in FVC (n=13, mean 42 months). These results suggest that clearance of diethylenetriamine pentaacetate is preserved in patients likely to have pulmonary vascular disease and may be useful in distinguishing fibrosing alveolitis from vascular disease in systemic sclerosis. (au)

  17. Clearance of inhaled technetium-99m-DTPA as a clinical index of pulmonary vascular disease in systemic sclerosis

    Kon, O.M.; Daniil, Z.; Bois, R.M. du [Royal Brompton Hospital, Interstitial Lung Disease Unit, London (United Kingdom); Black, C.M. [Royal Free Hospital, Dept. of Rheumatology, London (United Kingdom)

    1999-01-01

    This study evaluated the utility of the clearance time of inhaled diethylenetriamine pentaacetate (DTPA) to distinguish pulmonary vascular disease from early fibrosing alveolitis (FA) in patients with systemic sclerosis (SSc) It was hypothesized that this would be preserved in patients with vascular disease compared with FA, despite similar gas-transfer deficits and matching lung volumes, because of the preservation of alveolar epithelial integrity. All patients had SSc and were categorized into a control group (C; n=9), pulmonary vascular group (VAS; n=14) or FA group (n=14) dependent on the appearance on a computed tomography (CT) scan and the transfer factor of the lung for carbon monoxide (TL,CO) (VAS and FA {<=}70%, C {>=}80%). All patients had a forced vital capacity (FVC) of >80%. The TL,CO (median) was similar in the VAS (57.5%) and FA (60%) groups. There was a significant difference in median DTPA clearance half-times between FA (21.25 min) and VAS (46.5 min) (p=0.014) and between FA and C (84.5 min) (p=0.0004). No difference was found between VAS and C (p=0.0778). Follow-up data from the VAS group showed no subsequent development of FA on the CT scan and no decrease in FVC (n=13, mean 42 months). These results suggest that clearance of diethylenetriamine pentaacetate is preserved in patients likely to have pulmonary vascular disease and may be useful in distinguishing fibrosing alveolitis from vascular disease in systemic sclerosis. (au) 22 refs.

  18. Study to improve the precision of calculation of split renal clearance by gamma camera method using 99mTc-MAG3

    Both fundamental and clinical studies were performed to improve the precision with which split renal clearance is calculated from the relation between renal clearance and the total renal uptake rate by using 99mTc-MAG3, which is mainly excreted into the proximal renal tubules. In the fundamental study, the most suitable kidney phantom threshold values for the extracted renal outline were investigated with regard to size, radioactivity, depth of the kidney phantom, and radioactivity in the background. In the clinical study, suitable timing to obtain additional images for making the ROI and the standard point for calculation of renal uptake rate were investigated. The results indicated that, although suitable threshold values were distributed from 25% to 45%, differences in size, solution activity, and the position of the phantom or BG activity did not have significant effects. Comparing 1-3 min with 2-5 min as the time for additional images for ROI, we found that renal areas using the former time showed higher values, and the correlation coefficient of the regression formula improved significantly. Comparison of the timing for the start of data acquisition with the end of the arterial phase as a standard point of calculating renal uptake rate showed improvement in the latter. (author)

  19. Study with radio aerosol of DTPA technetium-99 m in individuals with pulmonary disease by amiodarone

    In order to evaluate the role of the clearance of 99 m Technetium chelated to diethylenetriamine-penta-acetate (99 m Tc-DTPA) in amiodarone induced pulmonary disease, 40 individuals were studied in four groups. After spirometry, where a volume-time curve was registered, all individuals inhaled 740 MBq of 99 m Tc-DTPA diluted in 4 ml of saline, for five minutes. Pulmonary images were obtained in a computerized scintillation camera and 9 regions of interest were selected. (author)

  20. Application of measuring 99mTc-MAG3 plasma clearance based on one-compartment model (MPC method) to renal transplantation

    Measurement of 99mTc-MAG3 plasma clearance (CLmag) based on one-compartment model (MPC method) was applied to renal transplantation and evaluated for the factors which might affect the calculated results, especially concerning renal depth. Correlation coefficient of CLmag between MPC method using real renal depth and Russell or Bubeck single sampling method was good (r=0.852 or 0.876, respectively). Regression equation between MPC method and Russell method was y=1.044x-3.0 and was more closer to y=x than that between MPC method and Bubeck method. CLmag of MPC method calculated by estimated renal depth from the abdominal thickness was also similar to that by real renal depth. Even if the fixed renal depth, 4 cm, was applied, the coefficient and regression equation between MPC method and Russell method were r=0.884 and y=1.004x-10.2. In conclusion, MPC method is applicable to the evaluation of renal transplants. Though measuring renal depth is best, calculation with fixed renal depth of 4 cm might be practically acceptable. (author)

  1. Determination of glomerular filtration rate from plasma clearance with Tc99m.DTPA by single; two and multi-sample methods

    Background.The plasma sample method following a single injection of radioactive markers has been proved to be simple and accurate for the determination of glomerular filtration rate (GFR) in clinical practice. The aim of this study was to assess clinical accuracy of single-, two-and multi-sample methods. Patients and Methods. The study was performed on 50 patients with various degrees of renal dysfunction (29 males and 21 females; aged 27-90 years). As a reference the true GFR was determined by means of the two compartment model curve fitting 10 plasma following a single-injection of Tc99m-DTPA. The GFR was estimated by the three methods of single-, two and multi-sample between 75 and 300 min after the injection. The GFR by two and multi-sample methods was determined with the slope and intercept algorithm and its overestimation was corrected by Brochner-Mortensen's formula. Results. In all patients with a GFR between 12 and 169 ml/min/1.73m2, accuracy for the determination of GFR was identical in both the single-and five-sample methods. In 46 patients with a GFR higher than 30 ml/min/1.73m2, the single-sample method exhibited the lowest standard error of mean of difference in GFR. In 38 patients with a GFR lower than 120 ml/min/1.732, the two and five sample methods were more accurate than the single-sample one. The best combination of sampling time for the two samples was 120 min and 240 min after the injection. Conclusion. Accuracy of each plasma sample method depends on the preserved GFR. As a matter of practice, the single-sample method is the first choice for a patient who is expected to have a GFR higher than 30 ml/min/1.73m2. The two-sample method is indicated only in a patient with severe renal failure with a GFE lower than 30 ml/min/1.73m2 (au)

  2. Transplant renography: 99m-Tc-DTPA versus 99m-Tc-MAG3

    99mTc-MAG3 (mercaptoacetyltriglycine) has been proposed as a replacement for both 131I-hippuran and 99mTc-DTPA on clinical grounds. We undertook a prospective preliminary study to ascertain whether 99mTc-MAG3 works better than 99mTc-DTPA in the follow up of renal transplant recipients. Seventeen patients (21 renograms each MAG3 and DTPA) were studied, together, with a reference group of 10 patients in whom MAG3 and Hippuran clearance rates were determined simultaneously. As expected, 99mTc-MAG3 analog images were excellent and 99mTcMAG3 clearance correlated very well with 131I-hippuran clearance (r=0.978). MAG3 values were 60% of hippuran values. However, when the corresponding renographic and perfusion findings were faced with different diagnostic challenges, such as post transplant renal failure and rejection, 99mTc MAG3 did not differ from 99mTc-DTPA in a significant way. 99mTc-DTPA was superior to 99mTc-MAG3 in one case of rejection. (orig.)

  3. Comparison of clearance determination with sup 131 I-hippurate (split function ERPF) and sup 99m Tc-DMSA. Vergleich der seitengetrennten Nierenclearance mit der Leistungsbeurteilung mittels Technetium DMSA

    Illing, H.; Weiss, M.L.; Deckart, H. (Klinikum Berlin-Buch, Klinik fuer Nuklearmedizin und Endokrinologie (Germany))

    1990-01-01

    The capacity of separated kidney function, estimated by means of {sup 131}I- or {sup 123}I-hippurate clearance, was compared with the capacity results from {sup 99m}TC-DMSA scintigraphy. There was found a good correlation (0.98) of the two methods. In patients with urine congestion the frequent high capacity in hippurate clearance in comparison to DMSA-scintigraphy on the affected kidney was evident. This results needs further investigations. In cases where it is necessary to evaluate the relative separated capacity of both sides, the hippurate clearance can be substituted by combination of DMSA-scintigraphy and isotope renogram. Considering surgical consequences, it is important to carry out both methods. (orig.).

  4. Clinical application of 99mTc-DTPA-galactosyl serum albumin in hepatobiliary disease

    A clinical study with 99mTc-DTPA-galactosyl serum albumin (99mTc-GSA) was performed in 10 patients with hepatobiliary disease. In this study, scintigraphic data and images with 99mTc-GSA were compared with several serological liver function tests, the hepatic blood perfusion index and image quality using 99mTc-DTPA-human serum albumin (99mTc-HSA). Dynamic and serial hepatic images were obtained over a 20 min period after 99mTc-GSA injection, and time activity curves from the heart and liver were generated. The blood clearance index (HH15), and the hepatic uptake index (LHL15) were calculated from each curve of the heart and liver, respectively. In addition, using two compartment fitting, the blood clearance (KH1, KH2) index was calculated, and using exponential fitting, the hepatic uptake index (KL) was calculated. The mean HH15 in liver cirrhosis (LC) group and non-LC group was 0.81±0.05, 0.64±0.10, respectively. The mean LHL15 in LC group and non-LC group was 0.79±0.04, 0.91±0.06, respectively. There were significant differences between non-LC group and LC group in HH15, and LHL15, KH1, and KL. There were also significant correlations of KH1 with HH15, and KL with LHL15. Parameters of 99mTc-GSA showed significant correlations with various liver functions. 99mTc-GSA scintigraphy showed clearer liver images in hepatobiliary disease than 99mTc-HSA. These results suggest that 99mTc-GSA scintigraphy is useful in estimating preserved liver function and hepatic morphology. (author)

  5. Effect of background region of interest and time-interval selection on glomerular filtration ratio estimation by percentage dose uptake of (99m)Tc-DTPA in comparison with (51)Cr-EDTA clearance in healthy cats.

    Debruyn, Katrien; Vandermeulen, Eva; Saunders, Jimmy H; Dobbeleir, André A; Ham, Hamphrey R; Peremans, Kathelijne

    2013-08-01

    Evaluation of glomerular function is a useful part of the diagnostic approach in animals suspected of having renal disease. Time-interval and background region of interest (bg ROI) selection are determining factors when calculating the glomerular filtration ratio (GFR) based on percentage uptake of (99m)technetium-labelled diethylene triamine penta-acetic acid ((99m)Tc-DTPA). Therefore, three different time intervals (60-120 s, 120-180 s, 60-180 s) and three different bg ROIs (C-shape, caudolateral, cranial + caudal) were investigated. In addition, global GFRs based on percentage dose uptake of (99m)Tc-DTPA for the different time-intervals and bg ROIs were compared with the global GFR based on (51)chromium-ethylene diaminic tetra-acetic acid ((51)Cr-EDTA) plasma clearance in nine healthy European domestic shorthair cats. Paired Student's t-tests and linear regression analysis were used to analyse the data. Different time intervals seemed to cause significant variation (P <0.01) in absolute GFR values, regardless of the choice of bg ROI. Significant differences (P <0.01) between bg ROIs were only observed in the 120-180s time interval between the C-shape and cranial + caudal bg ROI, and between the caudolateral and cranial + caudal bg ROI. The caudolateral bg ROI in the 60-180 s time interval showed the highest correlation coefficient (r = 0.882) between (99m)Tc-DTPA and (51)Cr-EDTA, although a significant difference (P <0.05) was present between both techniques. PMID:23349527

  6. Evaluation of lung epithelial permeability in the volatile substance abuse using Tc-99m DTPA aerosol scintigraphy

    Chronic inhalant use is associated with significant toxic effects, including neurological, renal, hepatic, and pulmonary damage. However, there is a paucity of reports regarding respiratory complications in inhalant abusers. The aim of this study was to evaluate pulmonary epithelial permeability in the volatile substance abuse (VSA) using technetium-99m-labeled diethylenetriamine pentaacetic acid (Tc-99m DTPA) aerosol scintigraphy. This study included 18 patients with volatile substance abuse and 18 volunteer controls. All of patients and controls were smokers. Tc-99m DTPA aerosol scintigraphy was performed in all cases. Time-activity curves from each lung were generated and clearance half-time (T1/2) of Tc-99m DTPA were calculated. T1/2 of whole lung was calculated as a mean of the T1/2 of left and right lung. The T1/2 values of Tc-99m DTPA clearance in the substance abusers were significantly decreased as compared to the control group with respective mean values of 28.86±8.44, and 62.14±26.12 min (p=0.001). It was seen Tc-99m DTPA clearance from lung was faster as the duration of substance abuse was increased. Tc-99m DTPA pulmonary clearance is markedly accelerated in the volatile substance abuse. This suggests that inhalant abuse of substance may produce abnormalities in pulmonary alveolo-capillary membrane function. (author)

  7. Quantitative renal function study using TC-99mDTPA and TC-99mDMSA

    In quantitative renal function studies using Tc-99m DTPA and Tc-99m DMSA, the kidney depth is an important factor to control the gamma rays' absorption by the soft tissue. However, to date, this renal depth has been estimated from the patient's height and weight according to the formula of Toennesen. In the present study, we measured the kidney depth by ultrasonography and so determined the renal uptake of Tc-99m DTPA and Tc-99m DMSA. Using the kidney depth as measured by ultrasonography, the correlation coefficient between renal uptake of Tc-99m DTPA and GFR (determined by the clearance method) was 0.878 and that between renal uptake of Tc-99m DMSA and ERPF (determined from paraaminohippuran clearance) was 0.945. On the other hand, using the kidney depth as calculated by Toenneren's formula, the correlation coefficient between Tc-99m DTPA uptake and GFR was 0.849 and that between Tc-99m DMSA uptake and ERPF was 0.891. Thus, the renal depth measured by ultrasonography provided a closer correlation than that calculated according to Toenesen's formula. (author)

  8. Inhalation scintiscanning of persons with healthy lungs and lung diseases using sup(99m)Tc-sulfur colloid with special regard to the mucociliary clearance

    It is reported about inhalation scintiscanning with radioaerosols under the application of a gamma camera and a magnetic core- and tape memory, providing an interactive display. 89 patients suffering form various pulmonary diseases and 10 test persons with healthy lungs were investigated. The scintigraphic photos were not only evaluated visually, but also according to quantitative parameters, i.e. left/right distribution, degree of central deposition and mucociliary clearance. The latter resulted to be the most informative quantitative diagnostic method. In the 10 test persons with healthy lungs the scintigraphic images always showed a homogeneous distribution of radioactivity and a mucociliary half-time of 9.7 or 11.9 hours respectively was found. A central bronchial carcinoma provoked on the affected side of the lungs a reduced deposition of radioactivity, an increased central deposition and an accelerated mucociliary clearance. In patients suffering from peripheral bronchial carcinoma, pneumonia, pleural processes, pulmonary infarction, pulmonary circular focus or pneumothorax, only inconstant areas of reduced radioactivity deposition could be detected. However, these areas differed by shape, intensity and location from the central bronchial carcinoma. In 3 patients with pulmonary embolism, no pathologic changes could be detected only then, when no infarction occurred. In this case, also the quantitative parameters were normal. With chronical obstructive pulmonary diseases, diseases of the pulmonary framework and in cases of bronchial asthma a clearly pathologic image of the distribution of radioactivity resulted in all cases; in these a differentiation could only be achieved by additionally considering the quantitative parameters. (orig./MG)

  9. 99mTc-EDTA and 99mTc-DTPA complexes as hydrological tracers

    The [99mTc-DTPA]2- and [99mTc-EDTA]1- were evaluated as radiotracers for short time hydrological studies. Their complex stability after labelling with 9.25 GBq of 99mTc, the behaviour against pH variations, from 5 to 9, in simulated solutions and in natural river waters and the sorption of these compounds on the river sediments, were tested in laboratory experiments. Finally field double tracing experiments were carried out for each of labelling complexes and Rhodamine WT. From recovery calculations not losses of the 99mTc activity were observed. The shape of the RTD curves of the [99mTc-DTPA]2- and [99mTc-EDTA]1were quite similar to the Rhodamine Wt ones. May be concluded that both complexes behaved conservatively on the studied environmental conditions. (author)

  10. Functional imaging of hydatid cysts with Tc-99m pertechnetate

    Aim: The main aim of this study was to evaluate the role of Tc-99m pertechnetate imaging in the management of hydatid cysts. Material and Methods: A total number of 10 patients with hydatid disease of the lungs were studied. Six had unilateral and four bilateral lung involvement. There were six males and four females (mean age= 31 years). In six patients serial planar images of the chest were obtained following intravenous injection of 2 mCi of Tc-99m pertechnetate using standard gamma camera computer systems. In few patients radioactivity was also introduced directly into the bronchus to detect the communicating channels (if any) between the cysts and respiratory system. Results: In all six patients active uptake of Tc-99m pertechnetate was seen immediately after intravenous injection of the radioactivity, and reaching a plateau by 3-5 minutes. On the other hand the time activity curve on the lungs showed a clear downward trend (clearance curve) from the very beginning. The legion (cyst) to background (lungs) count ratios in all cases were found to be consistently high, ranging from 3:1 to 5:1. In two patients additional lung cysts (undetected by CT or x-rays) were detected. In three patients in addition to the active cysts, several low activity lesions were also detected. These corresponded to dead, inactive or complicated (infected) hydatid cysts. In few patients where radioactivity was introduced directly into the respiratory tracts, communication between the cyst and the main bronchus was demonstrated in one. In one such patient, where the radioactivity was introduced into the respiratory tract, a few minutes later discrete focal lesions were seen in the liver suggestive of multiple active hydatid cysts in the liver (concentrating Tc-99m pertechnetate which has been absorbed from the tracheo-bronchial tree into the vascular compartment). Conclusion: Tc-99m pertechnetate is actively taken up by the hydatid cysts. The differential uptake of radioactivity in the

  11. Evaluation of usefulness of Tc-99m-GSA liver scintigraphy in chronic liver diseases

    Liver scintigraphy was performed using a newly developed radiopharmaceutical, Tc-99m-DTPA-galactosyl-human-serum-albumin (Tc-99m-GSA), which binds specifically to the receptors on the hepatic cell surface, in 15 patients with chronic liver disease. The scintigraphy was evaluated qualitatively and quantitatively, and the results were compared with those obtained from the Tc-99m-PMT or Tc-99m-sn-phytate scintigraphy, and the liver function tests. The Tc-99m-GSA scintigraphy showed clear liver images in chronic hepatitis. However, in liver cirrhosis, the liver images were not clear and the cardiac images still existed 40 minutes after administration of Tc-99m-GSA, suggesting that the image quality of the Tc-99m-GSA scintigrams may be inferior to that of Tc-99m-sn-phytate or Tc-99m-PMT in some cases of severe liver dysfunction. The time-activity curves of the heart and liver were analyzed by non-linear regression analysis. The clearance rate from plasma (Kd) were obtained from the time-activity curve of the heart, and the hepatic uptake rate (Ku), hepatic excretion rate (Ke) and peak time of hepatic uptake-excretion curve (PT) were obtained from the time-activity curve of the liver. Kd, Ku, and PT values were more significantly decreased or prolonged in the patients with chronic hepatitis. Kd, Ku, and PT values had positive correlations with the result of the serum liver function tests, ICG-R15 and ICG-K. Ku and PT values had also correlations with the histological degree of hepatic fibrosis. On the other hand, the indices obtained using Tc-99m-PMT or Tc-99m-sn-phytate did not have correlations with the histological degrees of hepatic fibrosis. It is concluded that the liver scintigraphy using Tc-99m-GSA may be useful and give different information from those with conventional liver scintigraphies in evaluating chronic liver diseases. (author)

  12. Comparative biological parameters for the evaluation of common renal pharmaceutical preparations. 99mTc-DTPA, 99mTc-GH, and 99mTc-DMSA

    This work is concerned on establishing the necessary comparative quality control biological parameters for the evaluation of locally produced renal pharmaceutical preparations viz. tin complexes of 99mTc-DTPA, 99mTc-GH, and 99mTc-DMSA using gel chromatography column scanning techniques. Radiochemical purity, labeling yields, organ distribution, blood clearance and plasma protein binding were used as a selected indicator for quality control. The higher renal accumulation and tissue distribution were apparent with 99mTc-DTPA in mice, while blood retention was considerably low. The blood clearance of 99mTc-DMSA was relatively slow, while that of 99mTc-GH was rapid. The binding of 99mTc- DTPA, 99mTc-GH and 99mTc-DMSA with plasma protein were found to be 5, 65, and 95 % at 1.0 h, respectively. The stability of these cold kits was not affected on storing at 37 deg C for 30 days. (author)

  13. 99mTc-Citrate versus 67Ga-citrate for the scintigraphic visualization of inflammatory lesions

    Citric acid was labeled with 99mTc with an efficiency of > 99%. The biodistribution of 99mTc-citrate was studied in mice with turpentine-induced abscesses in comparison to 67Ga-citrate. The max. abscess/muscle concentration ratios were 4.61 ± 1.92 (3 h) for 99mTc-citrate and 4.76 ± 2.04 (4 h) for 67Ga-citrate. Arthritis was induced in 10 rabbits by intra-articular injection of ovalbumin Scintigrams obtained 4 days later and at 3 h post-injection of 99mTc-citrate showed increased activity involving the synovium. The max. arthritic/contralateral knee ratio was 3.19 ± 1.29 (3 h) and 6.47 ± 3.71 (24 h) for 99mTc- and 67Ga-citrate, respectively. The blood clearance curve of 99mTc-citrate in rabbits was biexponential with a fast and a slow component, compared to mono-exponential clearance of 67Ga-citrate. In 10 patients with rheumatoid arthritis whole-body scintigrams and spot images of involved joints indicated localization of the tracer in inflamed tissues. The mean target-to-soft tissue ratios were 3.04 ± 0.81 and 4.95 ± 2.56 for 99mTc-citrate and 99mTc-MDP, respectively. Renal clearance of radioactivity was evident from the scintigrams. Our results demonstrated that 99mTc-citrate is effective as a radiopharmaceutical for the visualization of inflammatory lesions and may be preferred to 67Ga-citrate due to the ideal physical characteristics of the radionuclide, easy preparation, low cost, early accumulation and the preference for the renal route of excretion. (Author)

  14. Detection of alveolar epithelial injury by Tc-99m DTPA radioaerosol inhalation lung scan in rheumatoid arthritis patients

    Rheumatoid arthritis (RA) is a systemic autoimmune disorder primarily involving the joints. Lung alterations in RA may be primary or secondary to pharmacological treatments and may involve the alveoli, interstitium, airways and/or pleura. Technetium-99 m diethylenetriaminepentaacetic acid (Tc-99m DTPA) aerosol inhalation scintigraphy is a sensitive and noninvasive test commonly employed to assess pulmonary epithelial membrane permeability. The purpose of this study was to investigate the changes of pulmonary alveolar epithelial permeability in patients with RA, to determine the relationship between the clearance rate of Tc-99m DTPA and pulmonary function test (PFT) results, and to determine the relationship between the clearance rate of Tc-99m DTPA and clinical parameters of disease. Twenty-five patients with RA but without lung alterations were included in the study. The patients were 22 females, and 3 males; mean age 53.6±8.7 years. Technetium-99m DTPA aerosol inhalation scintigraphy was performed on the study and healthy control groups. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. There were no significant differences in the mean T1/2 or mean PI values between the RA patients and control subjects. No correlation was found between the mean T1/2 values of Tc-99m DTPA clearance and activity of RA, clinical values, or the spirometric measurements except FEV1/FVC and functional status in RA patients (p=0.02, p=0.01, respectively). However, a weak correlation was found between duration of disease and T1/2 values of Tc-99m DTPA clearance (p=0.006). PI values tended to correlate with FEF25-75, although, this was not statistically significant (p=0.057). This study shows that no changes occur in alveolar-capillary permeability in RA patients without lung alterations. (author)

  15. Evaluation of the liver function for patients with chronic liver diseases using 99mTc-galactosyl human serum albumin [99mTc-GSA] liver scintigraphy

    99mTc-galactosyl human serum albumin [99mTc-GSA] is a new scintigraphic agent which binds specifically to asialoglycoprotein-receptor on the hepatic cell membrane. The new liver scintigraphy using 99mTc-GSA was performed in 30 patients with chronic liver disease to evaluate the residual liver function. Two parameters were obtained from 99mTc-GSA time activity curves of both the heart and the liver. One was [HH15] (clearance index), which was the ratio of radioactivity of the liver at 15 min over that at 3 min after injection. The other was [LHL15] (receptor index), the ratio of radioactivity of the liver over that of the liver plus heart at 15 min. Significant decrease in LHL15 and increase in HH15 value were observed in accordance with severities of the liver damage and clinical aggravation. These parameters correlated significantly with Child-Pugh score, glucagon test, ICG-R15, serum albumin levels, cholinesterase, prothrombin time and hepaplastin test also. In conclusion, these findings indicate that 99mTc-GSA liver scintigraphy is useful for evaluating the liver flunction in patients with chronic liver disease. (author)

  16. Evaluation of changes of mean parenchymal transit time and de convoluted curve in actual rejected transplanted kidney by Tc-99m-DTPA

    Precise diagnosis of complication after renal transplantation is necessary for treatment decision making. Acute rejection is one of the most serious but treatable complications. It is well known that mean parenchymal transit time (MPTT) arises with decreased function of Kidneys. In this study we evaluated changes of MPTT and de convoluted curve to asses the diagnostic value of these parameters rejection. This investigation was carried out on 27 complicated transplanted kidneys (11 cases with acute rejection - A R- and 16 cases with other complication-O C-) and 13 normal grafts by Tc-99-DTPA scintigraphy. MPPT, the time of 20% (T 20) and %80 (T 80) of curve pla tue as well as the ratio of T 20/T 80 were calculated according to de convoluted curve. In normal grafts Matt was 2.03+0.54 which arise d in A R (4.05+0.2), P0.1) between Ar and O C, however, the ratio of T 20/T 80 was higher in A R compared to O C (2.41+0.23 versus 1.77+0.27, P<0.001). With consideration of 2.1 as T 20. T 80 threshold, sensitivity and accuracy values for diagnosis of A R were 90%, 87% and 89% respectively. MPTT is a sensitive parameter to diagnosis of complicated transplanted kidney, but with calculation of T 20/T 80, we can obtain an accurate parameter for diagnosis for of acute rejection

  17. Urinary bladder blood flow. I. Comparison of clearance of locally injected 99mtechnetium pertechnate and radioactive microsphere technique in dogs

    Krøyer, Kristian; Bülow, J; Nielsen, S L; Kromann-Anderson, B

    1990-01-01

    The blood flow of the dog urinary bladder measured by radioactive microsphere technique was compared to the clearance of locally injected 99mTechnetium pertechnate (99mTc) in the bladder wall. In semilogarithmic plots the 99mTc washout curves showed a multiexponential course. From the initial slo...

  18. Evaluation of 99mTc-Mercaptoacetyltriglycine-Biocytin as a new hepatobiliary imaging agent in mice coinjected with bilirubin

    We evaluated 99mTc-labeled mercaptoacetyltriglycine (99mTc-MAG3)-biocytin as a hepatobiliary imaging agent in the absence and presence of bilirubin in mice. We then compared its pharmacokinetic parameters; peak liver/heart activity ratio (rmax) and half clearance time (HCT) with those of 99mTc-labeled diisopropyl-iminodiacetic acid (99mTc-disofenin). Balb/c mice were injected intravenously with hepatobiliary agent (99mTc-MAG3-biocytin or 99mTc-disofenin) alone or in combination with bilirubin at two doses (7 and 14 mg/kg) dissolved in 5% human serum albumin. Images were acquired every 15 s for 30 min with a gamma-camera equipped with a pinhole collimator. Dynamic images showed rapid hepatic uptake of 99mTc-MAG3-biocytin, with rapid clearance from the blood and rapid excretion via the biliary system. Its hepatic uptake was not affected by bilirubin coinjection, whereas 99mTc-disofenin coinjected with bilirubin showed a higher blood background than 99mTc-disofenin alone. These qualitative findings were reflected in pharmacokinetic parameters, rmax and HCT. The rmax was obtained from plots of time versus liver/heart activity ratios obtained in equal-area regions of interest over the heart and liver. The HCT was calculated from the hepatic clearance curve from plots of time versus liver activity. 99mTc-MAG3-biocytin without bilirubin coinjection showed an rmax of 8.9±1.3 and an HCT of 399±36 s. These values did not change even when 14 mg/kg of bilirubin were coinjected. By contrast, the parameters for 99mTc-disofenin with bilirubin were significantly (pmax was decreased from 7.9±2.5 to 1.4±0.2 and HCT was increased from 292±32 s to 782±133 s. 99mTc-MAG3-biocytin hepatobiliary scintigraphy in mice is not affected by bilirubin coinjection, and this hepatobiliary agent appears to offer promise for estimating hepatic function in patients with high bilirubin levels

  19. Measurement of effective hepatic blood flow using 99mTc-PMT SPECT and single blood sampling

    Effective hepatic blood flow (EHBF) was measured from an uptake constant using single blood sampling and 99mTc-PMT hepatobiliary SPECT data. After intravenous injection of 3 mCi (111MBq) of 99mTc-PMT, serial 1 min SPECT data were obtained for 7 minutes. A time activity curve (TAC) over the heart, that was normalized with the 5 minutes venous sample concentration (%/dose/m1), was used as a blood clearance curve (B(t)). And a TAC of the whole liver, that was normalized with the injected dose of 99mTc-PMT (%/dose), was used as a hepatogram (L(t)). An uptake constant representing EHBF, was estimated from the Rutland's method L. (t)/B(t) was plotted against ∫otB(t)dt/B(t), and the slope of the least square fitted straight line was determined as the uptake constant. In 16 cases, significant correlation was obtained between the 99mTc-PMT hepatic uptake at 5 minutes and the EHBF estimated from the blood clearance (r=0.85,p99mTc-PMT SPECT data enables us to estimate EHBF with single venous sampling and in relatively short acquisition time. This method is thought to be very valuable in clinical practice. (author)

  20. Uptake of {sup 99m}Tc tetrofosmin in lymphoma cell lines: a comparative study with {sup 99m}Tc sestamibi

    Ding, H.-J.; Shiau, Y.-C.; Tsai, S.-C.; Wang, J.-J.; Ho, S.-T.; Kao, Albert E-mail: albertkaotw@yahoo.com.tw

    2002-06-01

    Technetium-99m ({sup 99m}Tc) tetrofosmin has been used as a tumor-seeking agent. However, its role in detecting lymphomas has not been widely investigated. The aim of the present study was to determine the uptake and clearance characteristics of {sup 99m}Tc tetrofosmin in lymphoma cell lines. {sup 99m}Tc sestamibi was also evaluated for comparison. Three lymphoma cell lines (U-937: monocyte-like, histiocytic lymphoma, human; RAMOS: B-lymphoma cell line, American Burkitt lymphoma, lymphoblastoid, human; Hs445: Hodgkin's disease, lymphoid, human) were studied. After incubation of radiotracers {sup 99m}Tc tetrofosmin and {sup 99m}Tc sestamibi in medium for 0, 10, 20, 30, 60, 120 and 180 min, the uptake and clearance of each radiotracer were measured in the three lymphoma cell lines. The uptake of {sup 99m}Tc tetrofosmin was lower than that of {sup 99m}Tc sestamibi in these lymphoma cell lines. Among the three cell lines, Hs445 showed the greatest {sup 99m}Tc tetrofosmin uptake capacity. RAMOS and U-937 showed similar {sup 99m}Tc tetrofosmin uptake capacities. {sup 99m}Tc tetrofosmin accumulated in the three tested lymphoma cell lines, especially in the Hodgkin's disease cell line. However, in comparison with {sup 99m}Tc sestamibi, {sup 99m}Tc tetrofosmin may not be the best radiotracer for detection of lymphoma.

  1. Assessment of alveolar epithelial permeability in Behcet's disease with 99mTc-DTPA aerosol scintigraphy

    Behcet's disease (BD) is a multisystem disorder characterized by vasculitis, and consists of a triad of recurrent ulcers of the oral and genital mucosa with relapsing uveitis. The prevalance of pulmonary involvement varies in the range of 1-10% in various studies and its complications are severe and life threatening. In this study, we investigated the changes of pulmonary epithelial permeability of patients with BD using technetium-99m diethylene triamine penta-acetic acid (99mTc-DTPA) aerosol scintigraphy, so as to begin the therapy regimen as soon as possible. Twenty-one nonsmoking patients with BD (8 women, 13 men; mean age 38.67±8.86 years) and 15 healthy volunteer nonsmoking controls (8 women, 7 men; mean age 50.87±12.45 years) underwent 99mTc-DTPA aerosol inhalation scintigraphy and pulmonary function tests (PFTs). Subjects inhaled 1480 MBq of 99mTc-DTPA for 4 min in the supine position. Scintigraphic data were recorded dynamically (1 frame/min) in the posterior projection on a 64 x 64 matrix for a 30-min period using a double-headed gamma camera (Infinia, GE, Tirat Hacarmel, Israel) equipped with a low-energy all-purpose parallel hole collimator. Half time of 99mTc-DTPA clearance (T1/2) was calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was also calculated by dividing the peripheral total counts by the sum of the peripheral and central total counts on the first minute image, in order to quantify the distribution of the inhaled aerosol. The clearance half time of 99mTc-DTPA radioaerosols in the BD patients (24.81±6.22 min) was faster than in the normal control group (46.53±22.41 min) (P=0.004). There was also a significant difference between PI of the patients with BD (0.15±0.03) and that of the controls (0.21±0.06) (P=0.002). No correlation was found between the mean T1/2 values of 99mTc-DTPA clearance or the spirometric measurements in the BD patients. Penetration indices were not correlated with PET in the BD

  2. Tc-99m imaging agents

    A wide range of pharmaceuticals for labeling with Tc-99m, developed by the Soreq Radiopharmaceuticals Department, is described. Details of the production and quality control of 13 kits are given, as well as the range of results required for consistently high quality imaging agents

  3. Evaluation of quantitative split renal function testing methods using 99mTc-DTPA and 99mTc-DMSA renoscintigraphy in children with vesicoureteral reflux

    It is vital to accurately evaluate renal function in children with vesicoureteral reflux. To determine whether quantitative split renal function testing methods using 99mTc-DTPA and 99mTc-DMSA renoscintigraphy reflect renal function as accurately in children as in adults, 99mTc-DTPA and 99mTc-DMSA renoscintigraphies were performed in 21 children with vesicoureteral reflux within 5 days of each other for a total of 40 times. There were 12 boys and 9 girls ranging in age from 2 months to 16 years (mean, 6.8 years). The kidney depth was measured by ultrasonography. The correlation coefficient between 99mTcDTPA and 99mTc-DMSA total renal uptake was 0.275, and the correlation coefficients between 99mTc-DTPA and 99mTc-DMSA total renal uptakes and creatinine clearance were 0.402 and 0.522, respectively. The correlation coefficient between the accumulation count ratio (R/R+L) in 99mTc-DTPA and that in 99mTc-DMSA was 0.974. The total renal uptake obtained from 99mTc-DTPA and 99mTc-DMSA renoscintigraphy is not as reliable in children as in adults, and at present it is most appropriate to use a combination of accumulation count ratio (R/R+L) and 24 hr creatinine clearance value as examinations to evaluate general renal function. (author)

  4. Usefulness of L,L-ethylenedicysteine - 99mTc complex (EC-99mTc) for the kidney investigations

    To assess the usefulness of own EC-99mTc complex for the kidney function examination, the renoscintigraphy with EC-99mTc and clearance determinations were performed. During renoscintigraphy the kidney images were of superb quality, with overlaying organs (liver, spleen) not visualized. Renograms showed typical shapes, their TMAX and T1/2 values being insignificantly different from the obtained with other radiopharmaceuticals, used in renoscintigraphy (MAG3, hippuran). Very strict correlations were found between values of EC-99mTc and OIH-131I clearances (r=0.91) and excretion rate constants (r=0.92) of both radiopharmaceuticals. The correlation enabled formulation of an equation by which ERPF could be established from EC-99mTc clearance: ERPFOIH=1.245 x ClEC+51.52. On the basis of this equation a lower boundary of the normal EC-99mTc clearance was established; it amounts to 300 ml/min/1.73 m2. (author). 17 refs, 5 figs, 1 tab

  5. Scintigraphic and intraoperative scintimetric localization of an ectopic parathyroid adenoma with Tc-99m Tetrofosmin and Tc-99m Sestamibi

    Background: We report on a case of preoperative scintigraphic and intraoperative scintimetric confirmation of an ectopic parathyroid adenoma with Tc-99m Tetrofosmin in a 52-year old patient with persistent hyperparathyroidism after unsuccessful primary preoperative localization and reoperation. Methods: In preoperative localization study, dynamic, sequential static scans and SPECT of the neck and mediastinum were performed using Tc-99m Sestamibi and Tc-99m Tetrofosmin. Reoperation was performed by help of a hand-held gamma-probe for intraoperative scintimetric localization after preoperative injection of Tc-99m Tetrofosmin. Results: An ectopic adenoma could be detected preoperatively with both tracers. Tc-99m Tetrofosmin showed no significant difference in image quality vs. Tc-99m Sestamibi. The adenoma could also be detected scintimetrically by elevated count-rates. Conclusions: This case gives promise for Tc-99m Tetrofosmin to be a possible alternative in parathyroid imaging with similar imaging properties and slight theoretical advantages concerning background clearance, radiation exposure and constitution over Tc-99m Sestamibi. Intraoperative localization and confirmation of ectopic parathyroid adenoma, eventually with a geometrically adapted gamma-probe, seems to be possible. Whether there are significant advantages resulting in a possible reduction of operating time, should be evaluated in further studies. (author)

  6. Comparative radioanalytical and biokinetic studies of 99mTc-Tin and 99mTc-sulphur colloid kits

    Gel chromatography scanning technique (GCS) was used to study the radioanalytical behaviour of 99mTc-tin colloid and 99mTc-sulphur colloid kits. Sepharose has been found to be more accurate and versatile than the other conventional analytical procedures for radioanalytical evaluation of 99mTc-labelled colloids. The obtained radioanalytical results showed that 99mTc-sulphur colloid is more susceptible than the 99mTc-tin colloids to change due to the analytical environment. This is related to the nature of oxidation state of technetium atom in both colloids. The formation of 99mTc-tin colloid is achieved within few minutes after pertechnetate addition, while labeling of sulphur colloid is accomplished through a rather slow process. The organ distribution in mice shows that more than 90% of the injected dose of both colloids are accumulated in the liver, which proved the colloid labeling and optimal size particle. The minor size difference in the blood residual activity is due to the presence of hydrophilic stabilizer in 99mTc-sulphur colloid. The blood clearance study in rabbits showed that the biological half-times of activity disappearance of fast phase are longer periods extend to 125 and 65 minutes to 99mTc-tin and 99mTc-sulphur colloids, respectively. The in vitro plasma protein binding studies revealed by the GSC method showed that about 85% of 99mTc-tin colloid and 16% of 99mTc-sulphur colloid were bound to plasma protein, which proved that it does not influence the in vivo kinetics of both colloids

  7. QC studies and biological evaluations of three locally produced renal pharmaceutical preparations: 99mTc-DTPA, 99mTc-GH, and 99mTc- DMSA

    Quality control (QC) studies were done of three locally produced renal preparations of 99mTc- DTPA, 99mTc-GH and 99mTc-DMSA, as part of the production activity before the Gulf war. These studies were performed using gel chromatography column scanning (GCS) technique, although there are other alternative techniques. These kits were tested for radiochemical purity, and the labeling yields were found to be excellent. Biological studies included the following parameters: organ distribution (in mice, rats and rabbits), blood clearance in rabbits, and plasma protein binding in rats at different time intervals. Poor renal concentration of three agents in mice was significant at two time intervals. The tissue distribution in mice of DTPA, GH, and DMSA kits, which were stored at 37 deg. C for 30 days, after intravenous injection of the radioactivity at 5, 30, and 60 minutes, respectively, is presented. Blood retention of the renal agents was considerably low compared to those in rats and rabbits at the respective time intervals. The blood clearance of 99mTc-DMSA was relatively slow, and 99mTc-GH has rapid blood clearance, identical with that of 99mTc-DTPA for the first 20 minutes but slower thereafter. The binding of DTPA, GH and DMSA with plasma protein was 5, 65, 95 % at 1 h, respectively. Various amounts of tin (II) (as SnCl2), were used in the kits, with up to 10 times more of the usual dose for respective tin-complex. It was observed that there was no significant variation of the organ distribution in mice

  8. In vivo hepatic uptake inhibition study of Tc-99m-labeled hepatobiliary agents

    Kim, Meyoung Kon [National Institutes of Health, Bethesda (United States)

    1998-07-01

    We have previously reported that the hepatic uptake of Tc-99m-mercaptoacetyltriglycine (MAG3)-biocytin was not affected by coinjecting bilirubin in mice whereas the uptake of Tc-99m-diisopropyliminodiacetic acid (DISIDA) was inhibited (Kim et al. J Nucl Med, 38 : 50 p, 1997). The aim of this study was to investigate whether the hepatic uptake of Tc-99m-MAG3-biocytin or Tc-99m-DISIDA could be inhibited by biotin and biocytin. The Balb/c mice (female, 20g, n=5-8) were injected i.v. with the hepatobiliary agents alone (15-22 MBq/20-40 {mu}g) or together with inhibitors at two doses (14 and 28 mg/kg). For pharmacokinetic studies, images were acquired at 10-sec intervals for 20 min using a gamma camera equipped with a pin-hole collimator (d= 1 mm), starting immediately after intravenous injection. Pharmacokinetic parameters, peak liver/heart ratio (Rmax) and hepatic half clearance time (HCT), were calculated from liver and heart time-acitivity curves from regions-of-interest. Dynamic images showed rapid hepatic uptake inhibition was characterized by persistent high blood background. These qualitative scintigraphic findings were reflected in the pharmacokinetic parameters. Tc-99m-MAG3-biocytin without inhibitor coinjection showed Rmax of 9.3 and HCT of 383 sec. These parameters did not change significantly when bilirubin or biotin was coinjected, but did change significantly (P<0.05) for biocytin only at the higher dose: 52% decrease in HCT. In contrast, the parameters for Tc-99m-DISIDA (Rmax of 9.2 and HCT of 258 sec) were greatly affected (P<0.01) by biotin (79% decrease in Rman and 2-fold increase in HCT) even at 14 mg/kg concentration. We concluded that Tc-99m-MAG3-biocytin is less sensitive to inhibition by bilirubin, biotin, and biocytin than Tc-99m-DISIDA. Tc-99m-MAG3-biocytin appears to be a promising hepatobiliary imaging agent for hepatic function studies and may also be a useful tool to investigate the hepatic uptake mechanism of biotin derivatives in vivo.

  9. In vivo hepatic uptake inhibition study of Tc-99m-labeled hepatobiliary agents

    We have previously reported that the hepatic uptake of Tc-99m-mercaptoacetyltriglycine (MAG3)-biocytin was not affected by coinjecting bilirubin in mice whereas the uptake of Tc-99m-diisopropyliminodiacetic acid (DISIDA) was inhibited (Kim et al. J Nucl Med, 38 : 50 p, 1997). The aim of this study was to investigate whether the hepatic uptake of Tc-99m-MAG3-biocytin or Tc-99m-DISIDA could be inhibited by biotin and biocytin. The Balb/c mice (female, 20g, n=5-8) were injected i.v. with the hepatobiliary agents alone (15-22 MBq/20-40 μg) or together with inhibitors at two doses (14 and 28 mg/kg). For pharmacokinetic studies, images were acquired at 10-sec intervals for 20 min using a gamma camera equipped with a pin-hole collimator (d= 1 mm), starting immediately after intravenous injection. Pharmacokinetic parameters, peak liver/heart ratio (Rmax) and hepatic half clearance time (HCT), were calculated from liver and heart time-acitivity curves from regions-of-interest. Dynamic images showed rapid hepatic uptake inhibition was characterized by persistent high blood background. These qualitative scintigraphic findings were reflected in the pharmacokinetic parameters. Tc-99m-MAG3-biocytin without inhibitor coinjection showed Rmax of 9.3 and HCT of 383 sec. These parameters did not change significantly when bilirubin or biotin was coinjected, but did change significantly (P<0.05) for biocytin only at the higher dose: 52% decrease in HCT. In contrast, the parameters for Tc-99m-DISIDA (Rmax of 9.2 and HCT of 258 sec) were greatly affected (P<0.01) by biotin (79% decrease in Rman and 2-fold increase in HCT) even at 14 mg/kg concentration. We concluded that Tc-99m-MAG3-biocytin is less sensitive to inhibition by bilirubin, biotin, and biocytin than Tc-99m-DISIDA. Tc-99m-MAG3-biocytin appears to be a promising hepatobiliary imaging agent for hepatic function studies and may also be a useful tool to investigate the hepatic uptake mechanism of biotin derivatives in vivo

  10. Preparation of 99mTc kits for infection imaging

    The aim of this study was to label ubiquicidin fragment 29-41 (UBI) and biotin with 99mTc and evaluate their feasibility as infection imaging agents for in vivo use. 99mTc-UBI, labelled by a direct method, showed high in vitro and in vivo stability, specific uptake at the site of infection, rapid background clearance, minimal accumulation in non-target tissues and rapid detection of infection sites. 99mTc labelled biotin showed in vitro and in vivo stability, fast renal clearance and ability to detect infection and sterile inflammation processes in mice. Because of their stability and biological properties, both agents could be used in clinical applications. (author)

  11. Spiperone dithiocarbamate- 99mTc kit - a potential diagnosis agent for dopaminergic D-2 brain pathologies - biodistribution

    Psycho pharmacology has been discovering much about the D 2 dopamine receptors and their interrelationship to brain pathologies such as Parkinson's Disease, Schizophrenia and Huntington Disease. Those biological receptors have got affinity with dopamine endogenous agent, so that they complex and, in non pathological individuals, the biological receptors contribute to bring the levels of dopamine and free acetylcholine into equilibrium. The Spiperon Dithiocarbamate (SPDC) from Spiperon is synthesized and its complexation with Technetium-99 m has been prepared with its reaction parameters after being studied and improved. The SPDC- 99m Tc complex biological distribution has been made in Wistar rats and the uptake of spleen, heart, liver, stomach, lung, kidney, blood, intestine and brain have been resolved. The plasmatic clearance curve has been based on Wistar rats data and the Know-how of the kit ( for label SPDC with 99m Tc) has been achieved. (author)

  12. (99m)Tc-labeled therapeutic inhaled amikacin loaded liposomes.

    Lee, Jae-Ho; Cheng, Kenneth T; Malinin, Vladimir; Li, Zhili; Yao, Zhengsheng; Lee, Sung-Jin; Gould, Christine M; Olivier, Kenneth N; Chen, Clara; Perkins, Walter R; Paik, Chang H

    2013-12-01

    The radiolabeling of the liposome surface can be a useful tool for in vivo tracking of therapeutic drug loaded liposomes. We investigated radiolabeling therapeutic drug (i.e. an antibiotic, amikacin) loaded liposomes with (99m)Tc, nebulization properties of (99m)Tc-labeled liposomal amikacin for inhalation ((99m)Tc-LAI), and its stability by size exclusion low-pressure liquid chromatography (LPLC). LAI was reacted with (99m)Tc using SnCl2 dissolved in ascorbic acid as a reducing agent for 10 min at room temperature. The labeled products were then purified by anion exchange resin. The purified (99m)Tc-LAI in 1.5% NaCl solution was incubated at 4 °C to assess its stability by LPLC. The purified (99m)Tc-LAI was subjected to studies with a clinically used nebulizer (PARI eFlow®) and the Anderson Cascade Impactor (ACI). The use of ascorbic acid at 0.91 mM resulted in a quantitative labeling efficiency. The LPLC profile showed that the liposomal peak of LAI detected by a UV monitor at both 200 nm and 254 nm overlapped with the radioactivity peak of (99m)Tc-LAI, indicating that (99m)Tc-LAI is suitable for tracing LAI. The ACI study demonstrated that the aerosol droplet size distribution determined gravimetrically was similar to that determined by radioactivity. The liposome surface labeling method using SnCl₂ in 0.91 mM ascorbic acid produced (99m)Tc-LAI with a high labeling efficiency and stability that are adequate to evaluate the deposition and clearance of inhaled LAI in the lung by gamma scintigraphy. PMID:23879241

  13. Dynamic coupling of 99mTc-MIBI efflux and apoptotic pathway activation in untreated breast cancer patients

    Our previous studies showed that the efflux rate of technetium-99m methoxyisobutylisonitrile (MIBI) is directly correlated to P-glycoprotein (Pgp) levels in breast carcinoma. The aim of this study was to test whether the Pgp-dependent efflux of 99mTc-MIBI is related to the apoptotic pathway activation in breast carcinoma. Thirty-three untreated non-consecutive patients were intravenously injected with 740 MBq 99mTc-MIBI and serial images were obtained up to 4 h. The rate of efflux was determined by mono-exponential fitting of decay-corrected time-activity curves. Tumour specimens were then obtained at surgery and processed for the determination of the apoptotic index by in situ end-labelling of DNA fragments (Tunel). The rate of tumour cell proliferation was also determined using Ki67 monoclonal antibody. All breast carcinomas showed focal uptake of 99mTc-MIBI and the time to half clearance varied between 85 and 574 min. The apoptotic index ranged between 0.3% and 4.2%, whereas the rate of proliferation varied between 13% and 40%. We found a positive and significant correlation between the apoptotic index and the rate of proliferation (r=0.79, P99mTc-MIBI was directly and significantly correlated with the apoptotic index (r=0.74, P99mTc-MIBI (r=0.57, P99mTc-MIBI sequestration, a model for the dynamic coupling of Pgp-dependent 99mTc-MIBI efflux and apoptotic pathway activation may be derived. (orig.)

  14. Radiopharmacokinetic data for 99mTc-ABP - A new radiopharmaceutical for bone scanning: Comparison with 99mTc-MDP

    Technetium-99m-labeled alendronate is a new radiopharmaceutical for bone scanning developed under strict quality control at the INNSZ. The purpose of this work was to compare the radiopharmacokinetic data and the dosimetry of 99mTc-ABP and 99mTc-MDP in 10 volunteers, after it was tested in laboratory animals. 99mTc-ABP has shorter mean residence time (MRT) and t(1(2)) β; is less protein bound; has a higher renal clearance; smaller Vdss, and similar bone uptake at 1 and 2 h. 99mTc-ABP gives less radiation exposure to the patient with a 740 MBq dose, and the quality of the bone scan is excellent. 99mTc-ABP is a better radiopharmaceutical than 99mTc-MDP for bone scanning

  15. Technetium-99m-diethyl-IDA instant kit

    A formulation of stannous-diethyl-IDA freeze-dried kit, containing 50 mg diethyl-IDA and 0.4 mg hydrated stannous chloride, to be labelled with technetium was developed for hepatobiliary scintigraphy. The organ distribution data of 99mTc-diethyl-IDA in mice for 60 min post injection were satisfactory. The radiopharmaceutical exhibits rapid blood clearance, great hepatic clearance and very short hepatocyte transit time. Uptake of the radiopharmaceutical was highest in mouse liver and intestine. The renal uptake of the HB agent in mice is relatively low. Blood clearance data showed that the HB agent is rapidly cleared. (author) 20 refs.; 4 tabs

  16. Results of hepatobiliary imaging using Tc-99m EHIDA

    Tc-99m labelled 2,6-diethylphenylcarbamoylmethyliminodiacetic acid (EHIDA) is a non-toxic radiopharmaceutical that was found to undergo rapid biliary excretion in a normal human, with accumulation of radioactivity in the gall bladder and intestine. Images in normal subjects and nonjaundiced patients showed rapid concentration of tracer by the liver and the passage of the same into the intestine within 15 to 40 minutes, with or without visualization of the gall bladder. In the jaundiced patient, the tracer blood clearance was delayed and urinary excretion was increased. Tc-99m EHIDA has been extensively investigated in 1634 patients to evaluate its performance in the diagnosis of hepatobiliary disorders

  17. The placental binding and transfer of radiopharmaceuticals II: Tc-99m Sestamibi, Tc-99m Tetrofosmin and Tl-201 Thallous Chloride

    It has been shown that some radiopharmaceuticals can cross the placental barrier and enter into fetal circulation. The objective of this study was to investigate placental transfer of cardiac perfusion imaging radiopharmaceuticals (Tc-99m sestamibi, Tc-99m tetrofosmin and TI-201 thallous chloride (Tl+ -201)) in pregnant guinea pigs and in-vitro mechanism of the transfer using human placental lobule. Pregnant guinea pigs in the first, second and third trimesters were used. Following intravenous injection of Tc-99m sestamibi, Tc-99m tetrofosmin or Tl+ -201 the guinea pig was imaged using a gamma camera; killed and the fetuses removed. Each fetus was then imaged separately using a low energy general-purpose collimator. The placentas, ovary, and fetal hearts, lungs, liver, kidneys and blood were then removed and the radio-activity in each organ along with a 1.0 ml standard solution was counted separately in a dose calibrator. For the in-vitro experiment, the effect of ouabain on the transfer of Tl+ -201 and tritiated water (as internal reference marker) in the maternal-fetal direction was studied in human placentas (collected postpartum) from normal uncomplicated pregnancies and suitable lobules perfused with either normal or ouabain-treated perfusate. The differential transport rate of Tl+ -201 in the maternal-fetal direction was measured as time taken in minutes for 50% fraction of Tl+ -201 (TR50 ) to be transported across the fetal vein and expressed as the ratio of the TR50 of Tl+ -201 to tritiated water (TR50 index). The following pharmacokinetic parameters were also measured: the area under the curve, clearance and absorption rate indices. Neither Tc-99m sestamibi nor Tc-99m tetrofosmin was transferred across the placental barrier while 1.7 ± 0.5% of the injected activity (0.027 ± 0.005 % per gram) of Tl+ -201 radioactivity during the third trimester was transferred across the placenta into fetal circulation. Most of the radioactivity from Tl+ -201 in the fetus

  18. Diagnosis of pulmonary infections with HIV (+) patients. Brought of aerosol DTPA-Tc99m and of Ga67 citrate

    The pulmonary clearance of aerosol DTPA-Tc99m is a technology easy to use, well support by patients with immediate results. With the pneumonia at Pneumocystis Carinii (PPC), the clearance is more sensitive and more specific than the thoracic scintigraphy with Ga67. Used with a thorax radiography, results will lead to three directions: High probability of PPC, di phasic curve and very fast T50, equal inferior to 5,10 mn. Low probability of PPC, monoexponential curve and abnormal thorax radiography or di phasic curve with a value T50 superior to 5,10 mn. With these patients other explorations will be made (Ga67, biopsy) and if possible search pulmonary tuberculosis. Extra pulmonary pathology: monoexponential curve associated with a normal thoracic radiography. 2 figs

  19. Quantitative Evaluation of Liver Function Using 99mTc-DISIDA Cholescintigraphy

    Since hepatocyte clearance, leading edge parenchymal transit time and biliary excretion can be evaluated separately with hepatobiliary scan using 99mTc-DISIDA, hepatobiliary scan may be useful in differentiating intrahepatic cholestasis from extrahepatic cholestasis. Excretory liver function was analysed in 13 healthy subjects and 11 patients with clinically suspected hepatocellular disease and 9 patients with extrahepatic biliary obstruction confirmed by surgery, radiological and clinical evidence. Indices of total liver activity (% TLA), liver parenchymal uptake (% LPU), heart pool clearance (% HPC) and liver-heart rate (% LHR) were calculated from time activity curve over heart and liver. Compared with healthy subjects, significant reduction(p<0.05) in total liver activity (% TLA) and liver-heart rate (% LHR) was observed in all patients group. But no useful indices was demonstrated in differentiating hepatocellular disease from extrahepatic biliary obstruction.

  20. 99mTc-interleukin-2 and 99mTc-HMPAO granulocyte scintigraphy in patients with inactive Crohn's disease

    Crohn's disease (CD) is a chronic inflammatory bowel disease that may involve the whole gut. Marked intestinal T cell and macrophage activation is a key feature of the disease. Polymorphonuclear cell infiltration is also observed in the diseased gut, mainly during active inflammation. Scintigraphic detection of granulocytes and activated lymphocytes infiltrating the gut wall may be useful in identifying a subgroup of patients with clinically inactive CD who are undergoing early clinical relapse. The aims of the present study were (a) to compare the effectiveness of scintigraphy with 99mTc-labelled interleukin-2 (99mTc-IL2) and with 99mTc-HMPAO labelled granulocytes (99mTc-WBC) in detecting the presence and extent of bowel inflammation in patients with long-term inactive CD (>12 months) and (b) to assess the accuracy of these techniques in predicting future disease relapse. We studied 29 patients with ileal and/or colonic CD in stable clinical remission (Crohn's Disease Activity Index 99mTc-IL2 and 99mTc-WBC scintigraphy in order to evaluate the extent of acute and chronic inflammation in the bowel. Planar and single-photon emission tomography images were acquired in each patient at 1 h p.i. For quantitative analysis of 99mTc-IL2 uptake, the abdomen was divided into 32 regions of interest. Despite the absence of symptoms, 18 patients (62%) showed a positive 99mTc-IL2 and 18 (62%) a positive 99mTc-WBC scan. Only 12 patients (41.4% of the total group) were positive on both scans, and the sites of IL2 and granulocyte bowel uptake were usually located in different segments, indicating that in CD, acute and chronic inflammation can be present in different sites. As far as the prognostic role of the two scans in predicting future disease relapse is concerned, both 99mTc-IL2 and 99mTc-WBC scintigraphy showed a high negative predictive value (1.00 and 0.91, respectively) but a weak positive predictive value (0.44 and 0.39, respectively). Nevertheless, Kaplan-Meier curves

  1. Evaluation of quantitative split renal function testing methods using {sup 99m}Tc-DTPA and {sup 99m}Tc-DMSA renoscintigraphy in children with vesicoureteral reflux

    Nozaki, Tomoji; Kajimoto, Teruho; Nakamura, Koichiro; Kitatani, Hideki; Konuma, Kunio; Kohno, Miyuki; Okii, Kazuya [Kanazawa Medical Univ., Uchinada (Japan)

    1995-06-01

    It is vital to accurately evaluate renal function in children with vesicoureteral reflux. To determine whether quantitative split renal function testing methods using {sup 99m}Tc-DTPA and {sup 99m}Tc-DMSA renoscintigraphy reflect renal function as accurately in children as in adults, {sup 99m}Tc-DTPA and {sup 99m}Tc-DMSA renoscintigraphies were performed in 21 children with vesicoureteral reflux within 5 days of each other for a total of 40 times. There were 12 boys and 9 girls ranging in age from 2 months to 16 years (mean, 6.8 years). The kidney depth was measured by ultrasonography. The correlation coefficient between {sup 99m}TcDTPA and {sup 99m}Tc-DMSA total renal uptake was 0.275, and the correlation coefficients between {sup 99m}Tc-DTPA and {sup 99m}Tc-DMSA total renal uptakes and creatinine clearance were 0.402 and 0.522, respectively. The correlation coefficient between the accumulation count ratio (R/R+L) in {sup 99m}Tc-DTPA and that in {sup 99m}Tc-DMSA was 0.974. The total renal uptake obtained from {sup 99m}Tc-DTPA and {sup 99m}Tc-DMSA renoscintigraphy is not as reliable in children as in adults, and at present it is most appropriate to use a combination of accumulation count ratio (R/R+L) and 24 hr creatinine clearance value as examinations to evaluate general renal function. (author).

  2. Glomerular filtration values obtained with 99mTc-DTPA v/s measurements of creatinine Clearance and calculation of the filtered glomerular using the Schwartz formula in a pediatric population

    We compare glomerular filtration rate by DTPA Renogram (DTPA-GFR) with creatinine clearance (CC) and Glomerular filtration rate from Schwartz formula (Schwartz-GFR). The need for using (DTPA-GFR) method raised from the practical difficulties in getting an accurate (CC) in pediatric population. From Sep-2001 to May-2005, 48 patients aged 1month to 18 years, underwent (DTPA-GFR) and (Schwartz-GFR). 18 had also (CC). Comparison were made among these measurements also accounting for age groups. We found a better correlation between (DTPA-GFR) and (CC) Pearson = 0,895. (Schwartz)/(CC) comparison showed a slightly lower correlation Pearson = 0,857. The worst correlation was found comparing (DTPA-GFR)/(Schwartz-GFR) in children < 3 yr Pearson = 0,560. As we found a better correlation between (DTPA-GFR)/(CC) than (DTPA-GFR)/(Schwartz-GFR), DTPA-GFR could be considered reliable method in evaluating renal function in children having difficulties to get a Creatinine Clearance (au)

  3. Diagnostic efficiency of sup(99m)Tc-phytic colloid in the studies of hepatosplenic area

    High diagnostic efficiency of sup(99m)Tc-phytic frostimag colloid for studies of the anatomic-topographic characteristics of the liver and spleen, and its advantages over sup(99m)Tc-sulphide colloid for studies of splenic clearance have been shown. The profile scanner (MNIRRi-GAMMA) was used for the quality control over the preparation of Tc-labelled colloids

  4. Comparison of the Relative Renal Function Calculated with 99mTc-Diethylenetriaminepentaacetic Acid and 99mTc-Dimercaptosuccinic Acid in Children.

    Çelik, Tanju; Yalçin, Hülya; Günay, Emel Ceylan; Özen, Aynur; Özer, Cahit

    2014-09-01

    The aim was to compare the relative renal functions measured with technetium-99m dimercaptosuccinic acid (99mTc-DMSA) and technetium-99m diethylenetriaminepentaacetic acid (99mTc-DTPA) in children with renal diseases. Relative renal function of 128 children who applied to three hospitals from 2009 to 2011 were analyzed retrospectively. The mean value measured with 99mTc-DTPA and 99mTc-DMSA were 51.58 ± 14.95 and 51.96 ± 14.99 for the right kidney, 47.87 ± 15.27 and 47.94 ± 15.17 for the left kidney, respectively. A significant positive correlation was found between the relative renal functions (r = 0.963, P renal function, 99mTc-DTPA can be another choice for the calculation of relative renal function without a complementary DMSA scan particularly in pediatric patients who require renogram curve and GFR calculations. PMID:25538484

  5. Complexes of technetium-99m with tetrapeptides, a new class of 99mTc-labelled agents

    Tetrapeptides are a class of N4-tetraligands that can efficiently bind 99mTc. In fact, tetrapeptides can be considered as derivatives of mercaptoacetyltriglycine (MAG3) in which the mercaptoacetyl moiety is replaced by a more stable and easier to handle aminoacyl group. Direct labelling of tetrapeptides with99m Tc in alkaline medium (pH ≥ 11) in the presence of stannous ions gave a high yield (>95%) of one or two (probably isomeric) radiochemical species. Exchange labelling at different pH values in the presence of stannous tartrate resulted in lower yields of the same 99mTc-labelled products as those formed during direct labelling. In addition, other radiochemical species were formed of which one was characterized as an oxotechnetium-complex with the cyclisized tetrapeptide. Tetrapeptides with a chiral centre in the first amino acid yield upon labelling with 99mTc two radiochemical species, probably the two diastereomers with an oxotechnetium core respectively syn and anti with respect to the substituent on the amino acid. Only one diastereomer was observed when the chiral carbon atom is located in the second or third amino acid. Electrophoresis indicated that these new 99mTc-labelled complexes are neutral in acidic medium and negatively charged in neutral and alkaline conditions. This correlates with a complex in which an oxotechnetium(V) group is bound to the ligand through three deprotonated nitrogen atoms of the amide functions and the free electron pair of the amine nitrogen atom. Biodistribution in mice showed for all studied 99mTc-labelled tetrapeptides a rapid clearance from the blood mainly by the renal system. The presence of a methyl substituent in the tetrapeptide increased the urinary excretion. 99mTc-labelledl -glycylalanylglycylglycine showed in mice a urinary excretion comparable to that of 99mTc-MAG3. Further rise of lipophilicity by introduction of a dimethyl, isopropyl or isobutyryl group leads to increased hepatobiliary handling. It is

  6. Comparison of renal scintigraphy with sup(99m)Tc-gluconate and sup(99m)Tc-DMS

    Recently sup(99m)Tc-gluconate and sup(99m)Tc-dimercaptosuccinic acid (DMS) have been developed and used clinically as radiopharmaceuticals for renal scintigraphy. The author studied the renal uptake and body distribution of these two radio-pharmaceuticals experimentally using rats. A scinticamera equipped with a computer was utilized for dynamic curves in the clinical studies. sup(99m)Tc-gluconate was rapidly cleared from the blood and excreted in the urine. Renal uptake was rapid initially and then showed a gradual decrease. sup(99m)Tc-DMS, on the other hand, was slowly cleared and excreted. Renal uptake increased slowly and then levelled off. In clinical studies, sup(99m)Tc-gluconate provided valuable additional information about the renal collecting system in the early phase after injection. And the late scintigraphy with sup(99m)Tc-DMS was beneficial in demonstrating the kidneys of a patient with severe renal damage. Although some differences could be found in the distribution of these agents, both gave good renal images and seemed to be suitable radiopharmaceuticals for renal scintigraphy. (J.P.N.)

  7. Evaluation of total renal function from 99mTc-MAG3 scintigraphy in children

    Aim: The aim of the present study was to evaluate the usefulness of dynamic scintigraphy in the assessment of total renal function in children. The Patlak slope of 99mTc-MAG3 renography curves were compared to the plasma clearance values of 51Cr-EDTA. Material and methods: The study sample consisted of 53 boys and 33 girls with various nephrologic disorders, referred for routine clinical reasons. The median age of the subjects was 5.1 years (range 0.3 - 14.1 years). Imaging procedure. In supine position, the patient received a bolus injection of 1 MBq/kg, (minimum 10 MBq) 99mTc-MAG3 and a posterior dynamic gamma camera registration was performed for 21 min using 1 frame per second during the first minute and thereafter 10 seconds frames. Data analysis. Time-activity curves were generated from manually drawn heart and renal regions of interest. The MAG3 uptake was calculated from the Patlak-Rutland plot of each kidney by linear curve fitting until the beginning of the excretory phase. A sum of the slope values was used as a measure of total renal MAG3 uptake. Cr-EDTA clearance. Glomerular filtration rate (GFR) was measured from the plasma clearance of 51Cr-EDTA using single injection, multiple-sample technique. After intravenous injection of 51Cr-EDTA (74 kBq/kg for children up to 7 years, 37 kBq/kg for children older than 7 years), blood samples were drawn at 5, 10, 15, 45, 60, 120 and 180 min for radioactivity measurement. The GFR was calculated according to Broechner-Mortensen and expressed in ml/min. Results: The absolute 51Cr-EDTA clearance varied from 9 to 143 ml/min. There was a close linear relationship between 51Cr-EDTA clearance and MAG3 uptake (Fig). The correlation coefficient was 0.90 and the regression equation (y=43.5 x + 664). Conclusions: In the present study, there was a good correlation between plasma clearance of 51Cr-EDTA and the sum of the Patlak slopes. The regression equation can be utilised to transform the 99mTc-MAG3 uptake to an estimate

  8. ''In vitro'' and ''in vivo'' studies 2,6 - diisopropyl-fenil-carboilmethyl iminodiacetic acid labeled with99mTc (Disida -99mTc)

    The ''in vivo'' and ''in vitro'' studies on DISIDA -99mTc at the hepatobiliary level were made. The binding of DISIDA -99mTc to plasmatic proteins and the fraction at which this binding occurs were determined. The distribution coefficient in n-octanol/saline solution was 0.41 showing the lipophilicity of the compound. The images in rats show the biological distribution as well as the hepatobiliary clearance of the radiopharmaceutical under its unmetabolized form. (author)

  9. Cyclotron Production of Technetium-99m

    Gagnon, Katherine M.

    Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

  10. Technetium-99m Sestamibi in Multiple Myeloma

    Technetium-99m 2-methoxy - isobutyl - isonitrile (99mTc-MIBI) has been reported to be useful in evaluating patients with multiple myeloma. The aim of this study is to evaluate the role of technetium-99m sestamibi (99mTc-MIBI) scintigraphy in the diagnosis. staging and follow-up of patients with multiple myeloma. Methods and Materials: twenty-five consecutive patients with multiple myeloma were studied using 99mTc- MIBI. Of the 25 patients included in this study, 6 were in stage I, II in stage II and 8 in stage III. Anterior and posterior whole-body imaging were obtained 20 min after I.V. injection of 740 MBq of 99mTc-MIBI. Four different MIBI patterns could be described in our patients: physiological (P), diffuse (D), focal (F) and combined diffuse and focal (D+F). All patients in stages II and III as well as 3 patients in stage I were treated with chemotherapy (cyclophosphamide and prednisone) then 99mTc-MlBI scans were repeated after 6 courses. Results: in comparison to conventional X-ray skeletal survey, 99mTc-MIBI scans showed a higher number of myeloma bone disease at diagnosis. All patients with stage II and III multiple myeloma were positive with 99mTc-MlBl scans at diagnosis. The pattern of positive MIBI accumulation was diffuse in 13 (52%) patients, focal in 4 (16%) and combined focal and diffuse in 6 (24%) patients. The intensity of 99mTc-MIBI correlated with disease activity as determined by lactate dehydrogenase (LDH), number of plasma cells in bone marrow and serum electrophoresis. There was a direct correlation between 99mTc-MIBI scan result and clinical outcome of patients following 6 courses of chemotherapy. Sensitivity and specificity of 99mTc-MIBI scintigraphy in detecting myeloma bone lesions were 92% and 90% respectively. Conclusion: 99mTc-MIBI scintigraphy is a reliable method to evaluate bone marrow activity in patients with multiple myeloma and follow-up of myeloma bone lesions

  11. 99mTechnetium labelled Escherichia coli

    Samples of a culture of unlabeled Escherichia coli were incubated with different concentrations of stannous chloride for various time periods. 99mTc (26.0 MBq) was added to each preparation and the results showed a labelling yield of 98% for E. coli. Since the bacterial viability of 99mTc-E. coli and E. coli did not show any statistical differences, these results demonstrate that labelling of E. coli with 99mTc does not modify the bacterial viability, and the radiolabelled bacteria may be a good model to study bacterial translocation

  12. Detection of alveolar epithelial injury by 99mTc-DTPA radioaerosol inhalation lung scan following blunt chest trauma

    DTPA clearance rate is a reliable index of alveolar epithelial permeability, and is a highly sensitive marker of pulmonary epithelial damage, even of mild degree. In this study, 99mTc-DTPA aerosol inhalation scintigraphy was used to assess the pulmonary epithelial membrane permeability and to investigate the possible application of this permeability value as an indicator of early alveolar or interstitial changes in patients with blunt chest trauma. A total of 26 patients was chest trauma (4 female, 22 male, 31-80 yrs, mean age; 53±13 yrs) who were referred to the emergency department in our hospital participated in this study. Technetium-99m diethylene triamine pentaacetic acid (DTPA) aerosol inhalation scintigraphy was performed on the first and thirtieth days after trauma. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. On the first day, mean T1/2 value of the whole lung was 63±19 minutes (min), and thirtieth day mean T1/2 value was 67±21 min. On the first day, mean PI values of the lung and 30th day mean PI value were 0.60±0.05, and 0.63 ±0.05, respectively. Significant changes were observed in radioaerosol clearance and penetration indices. Following chest trauma, clearance of 99mTc-DTPA increased owing to breakdown of the alveolar-capillary barrier. This increase in the epithelial permeability of the lung appears to be an early manifestation of lung disease that may lead to efficient therapy in the early phase. (author)

  13. Experimental studies on imaging of infected site with 99mTc-Iabeled ciprofloxacin in mice

    ZHANG Hong; JIANG Ning-yi; ZHU Lin

    2009-01-01

    Background Bacterial infection can pose a substantial diagnostic dilemma.99mTc-labeled ciprofloxacin (CPF) was developed as a biologically active radiopharmaceutical to diagnose infection.In the present research,we studied the biodistribution and imaging properties of infection tracer 99mTc-CPF in a mouse model of infection.Methods CPF was labeled with 99mTc and the radiochemical purity and labeling rate were measured.A mouse model of infection was established.We then determined the biodistribution of 99mTC-CPF and conducted the whole body scintigraphy of the animal model.Results 99mTc-Ciprotech was stable for at least 6 hours at room temperature.The labeling rate of CPF by 99mTc was over 90%.Clearance of radioactivity mainly occurred in the liver and kidney,and the clearance from blood was rapid.Both biodistribution and imaging results showed higher uptake of 99mTc-CPF at sites of infection.The infectious tissue/normal tissue ratio peak was 4.30 at 4 hours after injection.Conclusions 99mTc-CPF is a sensitive radiopharmaceutical for scintigraphy of infectious lesions and it is easy to prepare.

  14. Technetium-99m-human fibrinogen

    Exogenous fibrinogen has been successfully labeled with /sup 99m/Tc using a modified electrolytic method. The exact labeling mechanism has not been determined. Experimental data suggest that the labeling process of /99m/Tc-fibrinogen is quite similar to that of /sup 99m/Tc-human serum albumin as reported earlier by Benjamin. Technetium-99m-fibrinogen is stable in human plasma or in 1 percent buffered human serum albumin. A binding efficiency of 76 percent has been achieved with approximately 25 percent clottable protein. The entire labeling procedure requires less than 1 hr of preparation time. This short labeling time in a closed system may allow development of a practical method for labeling autologous fibrinogen, thus eliminating the risk of hepatitis transmission. (U.S.)

  15. Combined Tc-99m sesta MIBI scin

    Enas Abdel Ghany Ibrahim

    2015-12-01

    Conclusions: Accurate localization of adenomas should be obtained prior to surgery for minimal invasive surgical procedure. In this study, combined ultrasonography and Tc-99m MIBI improved localization of parathyroid adenomas.

  16. {sup 99m}Tc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    Okada, David R. [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Liu, Zhonglin [University of Arizona School of Medicine, Tucson, AZ (United States); Johnson, Gerald; Okada, Robert D. [University of Oklahoma Health Sciences Center, Oklahoma, OK (United States); University of Tulsa, Tulsa, OK (United States); Beju, Delia [Oklahoma State University School of Medicine, Tulsa, OK (United States); Khaw, Ban An [Northeastern University, Boston, MA (United States)

    2010-10-15

    {sup 99m}Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine {sup 99m}Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). {sup 99m}Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. {sup 99m}Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 {+-} 0.09) (cpm, SEM) than in control (1.74 {+-} 0.07), stunned (1.68 {+-} 0.11), and hibernating (1.59 {+-} 0.11) (p < 0.05). Tracer retention curves for ischemic-reperfused were elevated at all time points as compared with the other groups. {sup 99m}Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 {+-} 0.63) than in control (1.98 {+-} 0.15), stunned (1.79 {+-} 0.08), and hibernating (2.33 {+-} 0.15) (p < 0.05). The 60-min well-counted tracer activity ratio of ischemic-reperfused to control was 9:1 and corroborated the NaI detector results. Creatine kinase, triphenyltetrazolium chloride, and electron microscopy all demonstrated significantly greater injury in ischemic-reperfused compared to the other groups. An excellent correlation was observed between viability markers and tracer activity (r = 0.99 triphenyltetrazolium chloride; r = 0.90 creatine kinase). {sup 99m}Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. {sup 99m}Tc-glucarate uptake was strongly correlated with myocardial necrosis as

  17. Technetium-99m ceftizoxime kit preparation

    The aim of this work was to prepare a kit of 99m Tc-ceftizoxime (99m Tc-CFT), with stability and biological activity preserved, able to identify a septic focus (E. coli) in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/m L). After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99m Tc pertechnetate solution (Na 99m Tc O4-) with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92%, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99m Tc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli), the animals were anesthetized and 0.1 mL of 99m Tc-CFT (37 MBq) was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs) were calculated. The diameters of the inhibition halos for 99m Tc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99m Tc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99m Tc-CFT) by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes. (author)

  18. Biodistribution and dosimetry of 99mTc-ciprofloxacin, a promising agent for the diagnosis of bacterial infection

    This study reports on the biodistribution and dosimetry of technetium-99m ciprofloxacin, a radio-ligand developed for the visualisation of bacterial infection. Whole body scans were performed up to 24 h after intravenous injection of 370 MBq 99mTc-ciprofloxacin in three male and three female volunteers. Blood samples were taken at various times up to 24 h after injection. Urine was also collected up to 24 h after injection, allowing calculation of renal clearance and interpretation of whole body clearance. Time-activity curves were generated for the thyroid, heart, liver and whole body by fitting the organ-specific geometric mean counts, obtained from regions of interest. The MIRD formulation was applied to calculate the absorbed radiation doses for various organs. The images showed rapid, predominantly urinary excretion of 99mTc ciprofloxacin, with low to absent brain, lung and bone marrow uptake and low liver uptake and excretion. Accordingly, imaging conditions are excellent for both the thoracic and the abdominal region, even at early time points (60 min) post injection. In none of the volunteers was the gallbladder visualised. Approximately 60% of the injected activity was recovered in urine by 24 h post injection. The highest absorbed doses were received by the urinary bladder wall, the thyroid, the upper large intestine, the lower large intestine and the uterus. The estimated mean effective dose for the adult subject, taking into account the weight factors of the ICRP60 publication, was 0.0083 mSv/MBq. The amount of 99mTc ciprofloxacin required for adequate planar and tomographic imaging results in an acceptable effective dose to the patient. (orig.)

  19. Preparation and biodistribution of 99mTc-lomefloxacin and 99mTc-ofloxacin complexes

    This paper addresses the development of two new radiopharmaceuticals for imaging sites of infection. The optimization of the labeling yield of ciprofloxacin analogous, lomefloxacin and ofloxacin, with 99mTc was described. At ph 3.5 - 5 99mTc-lomefloxacin was obtained with a high radiochemical yield of 93.6 % by adding 99mTc to 2.5 mg lomefloxacin in the presence of 50 μ SnCl2 while 99mTc ofloxacin was obtained (96.6%) by adding 99mTc to 2 mg ofloxacin in tbe presence of 50μ g SnCl2. Biodistribution studies in rats were carried out in experimentally induced infection in the left thigh using Staphylococcus aureus. Both thighs of the rats were dissected and counted' and the ratio. of bacterial infected thigh/contralateral thigh was then evaluated. 99mTc-lomefloxacin showed higher uptake (T/NT = 6.5 ± 0.5) in the infectious lesion than 99mTc-ofloxacin (T/NT = 4.3 ± 0.6) and abscess-to-muscle ratios for both preparations were higher than that of 99mTc-ciprofloxacin (T/NT = 3.8 ± 0.8), indicating that 99mTc-lomefloxacin could be used instead of 99mTc-ciprofloxacin for imaging sites of infection

  20. Biokinetics and dosimetry in patients of 99mTc-EDDA/HYNIC-Tyr3-octreotide prepared from lyophilized kits

    99mTc-EDDA/HYNIC-Tyr3-octreotide (99mTc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for 99mTc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after 99mTc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99mTc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3±0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv

  1. The primary application of 99mTc labeled glucose: 99mTc-EC-DG in tumor imaging

    Purpose: 18F-FDG glucose metabolic imaging plays an important role. in. clinical, practice. But, because of the expensive price of PET machine and cyclotron, 18F-FDG imaging is not easy to access and has difficult availability. Now the research of technetium labeled glucose is a hotspot in nuclear medicine imaging agent development. The Purpose of this study is to primarily study the clinical application in tumor imaging of 99mTc labeled glucose: 99mTc-EC-DG. Method: EC-DG was synthesized according to a known procedure (Yang et al, Radiology 226: 465, 2003). Labeling of 99mTc-ECDG was achieved by means of adding the required amount of ECDG and tin (II) chloride to the pertechnetate. Radiochemical purity was assessed at radio-thin-layer chromatography, with 1 mol/L of ammonium acetate plus methanol (4:1) as the eluant. 18 patients (9 cases of lung cancer, 1 lymphoma, 1 hepatic cell cancer, 1 recurrence of gastric cancer, 1 recurrence of thyroid cancer, 1 recurrence of colon cancer, 1 lung metastasis of thyroid cancer, 1 pneumonia, 1 tuberculosis and 1 inflammation of breast) fasted 6 hours and then underwent the 99mTc-EC-DG imaging after the injection of 25 mci 99mTc-EC-DG intravenously, the planar and tomographic imaging was acquired 2 hours and 4 hours after the injection, and the ratio of tumor to normal tissue was calculated. 4 of the 15 cases of malignant tumor were performed 18F-FDG imaging contrastively. The machine used in this study is Axis dual-headed coincidence SPECT of PICKER company, and iterative reconstruction is used in data process. Result: brain is not imaged and kidneys are clearly imaged in 99mTc-EC-DG imaging, the blood clearance of 99mTc-EC-DG is slower than that of 18F-FDG, the blood pool of heart and big blood vessel is seen at the time of 2 hours after the injection of 99mTc-ECDG, and still visible at 4 hours, the uptake of muscle is low. 14 cases of malignant tumor had positive imaging result (14/15), T/N ratio of 2 hours is 1.36-5.64 (2

  2. Preparation and preliminary biological evaluation of 99mTc-ANMdU

    Technetium-99m-labeled-5-{2-sulfanylethyl-[2-(2-sulfanylethylamino)acetyl] amino}-methyl-2'-deoxy-uridine (99mTc-ANMdU) was reported. The precursor ANMdU was synthesized by six-step reactions and all intermediates were verified with MS and 1HNMR. Using SnCl2 as reducing agent, a labeling reaction was carried out at 100 degree C for 30 min. The radiochemical purity of the 99mTc-ANMdU was 96.68%. Partition coefficients were 0.92 and 0.70 at pH 7.0 and 7.4 of the phosphate buffer saline, respectively. Biodistribution of 99mTc-ANMdU in normal mice showed that the initial uptake of 99mTc-ANMdU in vivo and the clearance was rapid. (authors)

  3. Characteristics of radiopharmaceutical delivered from 99mTc-DTPA in the technegas generator

    99mTc-DTPA aerosol permeates the alveolar membrane by an intercellular pathway. Measurement of the clearance rate of 99mTc-DTPA aerosol is useful for assessing injury of the lung epithelium. Pertechnegas (P-gas) is also used to assess epithelial permeability, but its clearance is too rapid to evaluate lung epithelial permeability. The aims of this study were first to generate 99mTc-DTPA fine aerosol (D-gas), second to characterize D-gas by radiochromatography and an in vivo study in the rat, and third to investigate the clinical significance of D-gas in comparison with 99mTc-DTPA aerosol and P-gas. We generated D-gas in a chamber with an atmosphere of 3% oxygen and 97% argon inside the Technegas Generator. The clearance half-time of D-gas was 19.8±4.0 min in eight normal non-smoker subjects, 12.0±2.8 min in four smoker subjects, and 31±11.2 min in three with idiopathic interstitial pneumonia (IIP). In radiochromatography, the development of D-gas was the same as that of P-gas and different from that of 99mTc-DTPA solution. In the in vivo study using a rat, the distribution of intravenously injected D-gas solution was the same as that of 99mTcO4-, but different from that of 99mTc-DTPA solution. These results suggest that 99mTc-DTPA separates to free 99mTcO4- in the chamber of the Technegas Generator and that D-gas behaves in the same manner as P-gas. In conclusion, D-gas has no clinical significance for the assessment of epithelial permeability. (author)

  4. Technetium-99m ceftizoxime kit preparation

    Simone Odília Fernandes Diniz

    2005-10-01

    Full Text Available The aim of this work was to prepare a kit of 99mTc-ceftizoxime (99mTc-CFT, with stability and biological activity preserved, able to identify a septic focus (E. coli in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/mL. After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99mTc-pertechnetate solution (Na99mTcO4- with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92%, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99mTc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli, the animals were anesthetized and 0.1 mL of 99mTc-CFT (37 MBq was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs were calculated. The diameters of the inhibition halos for 99mTc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99mTc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99mTc-CFT by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes.O objetivo deste trabalho foi preparar um kit de Tc

  5. Under used technetium-99m generators

    Health care reform truly has become a global issue and it will undoubtedly have a dramatic impact on the future of nuclear medicine business in particular. A bigger concern within the nuclear medicine community is its competitiveness with other modalities and cost effectiveness.Technetium-99m and its generators are playing key role for the majority of diagnostic scans performed in the world today. Availability of ''9''9''mTc can be increased if it is separated from ''9''9Mo after much shorter growth times. After proper planning with the extra ''9''9''mTc, a significant number of scans can be performed or we would be able to order approximately 30% low activity ''9''9Tc generators to fulfill our requirements

  6. Can tumor uptake Tc-99m MDP

    Aim: To study a distribution of Tc-99m MDP in mice bearing tumor cell lines. Methods: The uptake of Tc-99m MDP was analyzed in seven human tumor cell lines (SPC-A1 adenocarcinoma of lung cancer, P37 Breast cancer, T24 Bladder cancer, SKOV2 Ovary carcinoma, Hela-229 Cervical carcinoma, Osteosarcoma, A375 Melanoma) and one mouse lung cancer cell line (Lewis). They were transplanted into 13, 4, 5, 5, 4, 5 athymic mice, 6 SCID nude mice and 4 C57 black mice, respectively. Approximately 10(7) cells of each cell line were injected subcutaneously into a right chest of mouse. After 5∼6 weeks, the Tc-99m MDP scintigraphy were determined 5-6 hours after i.v. injection of 74MBq in 0.05ml every mouse. Result: Biodistribution and tumor uptake MDP was different in the various cell types investigated. Region of interests (RIOs) placed on a small part of the tumor and horizontal copied to left chest or spine of mice in Tc-99m MDP imaging and the average count ratio (tumor to background ratio: T/B, tumor to spine ratio: T/NT) in each ROI was calculated. 13 nude mice bearing the adenocarcinoma (SPC-A1) were sacrificed and biodistribution was determined after Tc-99m MDP scintigraphy. Results were expressed as % injected dose/gram (%ID/g), mean±SD. T-ulcer=ulcer of tumor, T-round=surrounding of tumor, T-center=the center of tumor, Thor-sp=thoracic spine, Lum-ver=lumbar vertebra, LN=lymph node. Conclusions: Tumor can uptake Tc-99m MDP including adenocarcinoma. Higher uptake rate in the center tissue of tumor is than other part of tumor. It maybe connected with necrosis or fibrosis of tumor

  7. Alternative generators of 99mTc

    Full text: At the last years special attention is paid on reception and use of radiopharmaceutical preparation on the basis of 99mTc radioisotope. 99mTc is the most widely used radioisotope in nuclear medicine for today. Usually 99mTc radioisotope is received from its generator, in which as a parent radioisotope serves 99Mo. In the system, 99mTc and 99Mo radioisotopes are found in genetic balance and certain time interval, 99mTc radioisotope is separated from the system by chemical way. There are many ways of manufacturing and variants of the 99mTc generators. Nevertheless, investigators do not stop to search new methods of generator system. One of such methods can appear tube generators based on solid insoluble salts of Molybdenum with radioactive 99Mo. Such salts in our experiments were used molybdates Barium, Calcium and phosphorus molybdate Cesium. Here we present the solubility product of the specified salts: BaMoO4 - 4.10-8, Ca MoO4 - 4,7.10-9, Cs3 [P (Mo3O10)4] - 1,7.10-11. Salts of Barium and Calcium have been received by inclusion of 99Mo radioisotope into the chemical structure of salts at a stage of their synthesis by mixing solutions containing Ba+2, Ca+2 and 99MoO4-2 ions. Phosphorus molybdate Cesium has been received by mixing solutions containing Cs- and phosphorus molybdate (99Mo) - ions. The basic parameter of radioisotope generators is yield of daughter radioisotope from system. This parameter appeared to be equal to 77,6% in case of Phosphorus molybdate Cesium, 75,2% in case of molybdate Calcium and 70,8% in case of molybdate Barium. Preliminary results show that researches in this field can be continued

  8. Tc-99m MAG3 SPECT on transplanted kidney

    Ryu, Jong Gul; Kim, Soon; Zeon, Seok Kil [College of Medicine, Keimyung Univ., Taegu (Korea, Republic of)

    1999-08-01

    This study was designed to evaluate the usefulness of a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) single photon emission computed tomography (SPECT) performed on transplanted kidney. Thirty renal transplant patients were included in this study. Planar scan was performed for 30 minutes using 555 MBq Tc-99m MAG3. A post-voiding SPECT scan was acquired on the third, seventh, fourteenth and twenty eighth day after transplantation. SPECT scan showed interpretable image quality in 26 of 30 patients (86.7%) and 84 in 120 scans (70%). Fourteen of 26 patients with interpretable SPECT image showed decreased or increased radioactivity, but only 5 had abnormal findings on the planar scan. Focal SPECT defects were seen in allografts with normal function (n=3), acute tubular necrosis (n=3), and acute rejection (n=2). The defects are thought to reflect focally underperfused renal parenchyme or, in normal allografts, an artifact from uneven radioactivity distribution. Four of 10 paints with renal arterial variation showed focally decreased radioactivity and SPECT helped guide further studies that confirmed the exact cause. Five of 10 patients with acute tubular necrosis or acute rejection showed focally decreased radioactivity, but its relation to the patients' clinical course was not clear. Focally increased radioactivity was observed in 5 allografts with normal function and 1 with double ureter in which local clearance delay was observed. Tc-99m MAG3 SPECT renal scan can detect additional focal abnormalities compared to planar scan. Further study is necessary to elucidate the exact clinical significance of the SPECT findings.

  9. Tc-99m MAG3 SPECT on transplanted kidney

    This study was designed to evaluate the usefulness of a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) single photon emission computed tomography (SPECT) performed on transplanted kidney. Thirty renal transplant patients were included in this study. Planar scan was performed for 30 minutes using 555 MBq Tc-99m MAG3. A post-voiding SPECT scan was acquired on the third, seventh, fourteenth and twenty eighth day after transplantation. SPECT scan showed interpretable image quality in 26 of 30 patients (86.7%) and 84 in 120 scans (70%). Fourteen of 26 patients with interpretable SPECT image showed decreased or increased radioactivity, but only 5 had abnormal findings on the planar scan. Focal SPECT defects were seen in allografts with normal function (n=3), acute tubular necrosis (n=3), and acute rejection (n=2). The defects are thought to reflect focally underperfused renal parenchyme or, in normal allografts, an artifact from uneven radioactivity distribution. Four of 10 paints with renal arterial variation showed focally decreased radioactivity and SPECT helped guide further studies that confirmed the exact cause. Five of 10 patients with acute tubular necrosis or acute rejection showed focally decreased radioactivity, but its relation to the patients' clinical course was not clear. Focally increased radioactivity was observed in 5 allografts with normal function and 1 with double ureter in which local clearance delay was observed. Tc-99m MAG3 SPECT renal scan can detect additional focal abnormalities compared to planar scan. Further study is necessary to elucidate the exact clinical significance of the SPECT findings

  10. The determination of relative renal function in a pediatric population using Tc-99m DTPA and Tc-99m DMSA

    Rosen, P.R.; Kuruc, A.; Treves, S.T.

    1985-05-01

    Three methods for evaluating relative renal function in a pediatric population were compared. The clinical and nuclear medicine data of 73 patients were reviewed. Pertinent data included patient age, serum creatinine and the referral diagnosis (reflux, hypertension, obstructive uropathy). Time activity curves for renal regions of interest (ROI) were obtained by renography with Tc-99m DTPA, and deconvolved by an externally detected blood pool curve Furosemide was then administered to evaluate the renal collecting system (if indicated). This was followed by DMSA administration. Relative function was determined in 3 ways: 1) Accumulated renal DTPA activity 60-120 sec. following injection. 2) Amplitude of the tubular phase of the deconvolved renal curve and, 3) Accumulated Tc-99m DMSA activity in renal ROI 4 or 24 hrs. post-injection. Regression analysis revealed: 1) The basic relationship of relative functional data obtained by all three methods was not affected by creatinine, age or other factors. 2) The relationship between the three methods is linear and highly correlated. 3) The DMSA values may be predicted from either method of analyzing the DTPA study using appropriate predictor equations. The authors conclude that Tc-99m DMSA, due to its higher cost and more radiation exposure should not be used for the routine evaluation of relative renal function.

  11. Scintigraphy with technetium dimercaptosuccinic acid (99m Tc DMSA)

    Renal uptake of 99m Tc DMSA was used to evaluate the renal function of 16 healthy subjects (controls) and 115 patients with various urinary tract diseases. Scintigraphic examination was carried out 6 hours after an intravenous injection of the product. In the 16 controls Tc DMSA uptake was 25.7+-2.48% in the right kidney and 24.4+-2.86% in the left kidney. In 36 patients with one single hypertrophied kidney, there was a correlation (r=0.850) between creatinine clearance and Tc DMSA uptake, which was higher than in normal subjects (39.23+-9.9%). In the group of 68 patients with unilateral (31) or bilateral (37) renal disease, a significant correlation (r=0,725) was observed between kidney-to-kidney ratios of urea clearance and Tc DMSA uptake, so that renal impairment could be quantified. Quantitative scintigraphy did not appear to be of assistance in the remaining 11 patients with obstructive uropathy, as it overestimated renal function. The results obtained with 99 m Tc DMSA scintigraphy should be helpful in choosing between nephrectomy and conservative surgery and in assessing the degree of compensatory hypertrophy in single kidneys

  12. Comparative {sup 99m}Tc-MIBI, {sup 99m}Tc-tetrofosmin and {sup 99m}Tc-furifosmin uptake in human soft tissue sarcoma cell lines

    Rodrigues, M.; Chehne, F.; Sinzinger, H. [Dept. of Nuclear Medicine, University Hospital, Vienna (Austria); Kalinowska, W.; Zielinski, C. [Clinical Div. of Oncology, Department of Internal Medicine I, University Hospital, Vienna (Austria)

    2000-12-01

    The uptake characteristics of technetium-99m hexakis-2-methoxyisobutylisonitrile (MIBI), {sup 99m}Tc-tetrofosmin and {sup 99m}Tc-furifosmin in human soft tissue sarcoma cell lines were investigated and compared. After 10-120 min of incubation at 37 C, 32 C and 22 C with {sup 99m}Tc-MIBI, {sup 99m}Tc-tetrofosmin and {sup 99m}Tc-furifosmin, the kinetics of cellular uptake of these tracers in human soft tissue sarcoma cells SW 684 (fibrosarcoma), SW 872 (liposarcoma), SW 982 (synovial sarcoma) and SW 1353 (chondrosarcoma) was assessed. The uptake of {sup 99m}Tc-MIBI, {sup 99m}Tc-tetrofosmin and {sup 99m}Tc-furifosmin was temperature dependent. The kinetics of uptake of {sup 99m}Tc-MIBI and of {sup 99m}Tc-tetrofosmin was similar between fibrosarcoma and liposarcoma cells, as well as between synovial sarcoma and chondrosarcoma cells. {sup 99m}Tc-furifosmin showed similar uptake kinetics in all cell lines. The uptake of {sup 99m}Tc-furifosmin was, however, significantly higher in liposarcoma than in the other cells. The data indicate that the cellular uptake of {sup 99m}Tc-MIBI, {sup 99m}Tc-tetrofosmin and {sup 99m}Tc-furifosmin is dependent on cellular metabolic activity. (orig.)

  13. Comparative 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin uptake in human soft tissue sarcoma cell lines

    The uptake characteristics of technetium-99m hexakis-2-methoxyisobutylisonitrile (MIBI), 99mTc-tetrofosmin and 99mTc-furifosmin in human soft tissue sarcoma cell lines were investigated and compared. After 10-120 min of incubation at 37 C, 32 C and 22 C with 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin, the kinetics of cellular uptake of these tracers in human soft tissue sarcoma cells SW 684 (fibrosarcoma), SW 872 (liposarcoma), SW 982 (synovial sarcoma) and SW 1353 (chondrosarcoma) was assessed. The uptake of 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin was temperature dependent. The kinetics of uptake of 99mTc-MIBI and of 99mTc-tetrofosmin was similar between fibrosarcoma and liposarcoma cells, as well as between synovial sarcoma and chondrosarcoma cells. 99mTc-furifosmin showed similar uptake kinetics in all cell lines. The uptake of 99mTc-furifosmin was, however, significantly higher in liposarcoma than in the other cells. The data indicate that the cellular uptake of 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin is dependent on cellular metabolic activity. (orig.)

  14. Studies of labelling conditions for gentamicin with sup(99m)Tc. Complexation with ruthexium. Establishment of pharmacokinetics parameters through compartmental analysis

    Gentamicin sulphate is an aminoglycoside antibiotic type specifically used for treatment of infections produced by Gram-negative bacterias but at the other hand it presents ototoxic reactions as a serious side effect. The main purpose of labelling gentamicin with sup(99m)Tc was to obtain a radioactive tracer to carry out biological studies and compartmental analysis of this antibiotic. The optimal labelling conditions of gentamicin sulphate with sup(99m)Tc, using sodium pertechnetate solution eluted from a sup(99)Mo- sup(99m)Tc generator, were stablished by testing different masses of antibiotic, and reduction agent (SnCl sub(2).2H sub(2)O), and also different reaction time and final labelling PH. The same labelling procedure was used with Re (amonium perrenate) in order to obtain some semi-quantitative approximations of the chemical structure of the complex formed, since Re and Tc present similar chemical characteristics. In this way it is possible to suggest the role that the groups NH2 and C-O bonding of the gentamicin play in the complexation process. From the studies of the biological uptake of sup(99m)Tc-gentamicin sulphate in rats, the kidneys showed the highest affinity for the antibiotic. The maximum uptake was observed in 180 to 240 minutes followed by a decrease of it afterwards. For the dose and time used, no significative uptake by the auricular region was detected. Curve of plasma decay of sup(99m)Tc-gentamicin was obtained, and from the exponentials of each beanch of this curve respective half-lives were calculated. Furthermore the apparent volume of distribution was determined, and with the residual radioactivity in the body, the biological half-life and total clearance were obtained. The distribution of sup(99m)Tc-gentamicin in rats was set in a bi-compartments in addition to a retention one for the 24 hours time interval studied. (author)

  15. Studies of the myocardial uptake and excretion mechanisms of a novel 99mTc heart perfusion agent

    Introduction: 99mTc-TMEOP is a novel heart perfusion radiotracer exhibiting high initial and persistent heart uptake associated with rapid blood and liver clearance. This study aimed at determining the mechanisms of myocardial localization and fast liver clearance of 99mTc-TMEOP. Methods: Subcellular distribution of 99mTc-TMEOP was determined in excised rat heart tissue by differential centrifugation. The effect of cyclosporin A on the pharmacokinetic behaviour of 99mTc-TMEOP was evaluated by both ex vivo biodistribution and in vivo planar imaging studies. Results: Subcellular distribution studies showed that more than 73% of 99mTc-TMEOP was associated with the mitochondrial fraction. Comparison with subcellular distribution of 99mTc-sestamibi showed no significant difference in the mitochondrial accumulation between the two tracers. Biodistribution studies in the presence of cyclosporin A revealed an increase in kidneys and liver uptake of 99mTc-TMEOP, suggesting the involvement of multidrug resistance transporters in determining its pharmacokinetic profile. Conclusions: The heart uptake mechanism of 99mTc-TMEOP is similar to that of the other reported monocationic 99mTc cardiac agents and is associated with its accumulation in the mitochondria. Cyclosporin A studies indicate that the fast liver and kidney clearance kinetics is mediated by P-glycoprotein (Pgp), supporting the potential interest of this radiotracer for imaging Pgp function associated with multidrug-resistant tumours.

  16. MIBI-99mTc mammary scintigraphy

    121 patients suspected of breast cancer were studied with MIBI-99mTc to evaluate the suitability of the mammary scintigraphy in patients with doubtful cancer diagnosis.The results show 93 % sensitivity and 95 % specificity and indicate the usefulness of this procedure to increase the accuracy of the diagnosis

  17. An introduction to technetium-99m generators

    The role played by technetium-99m generators in diagnostic medicine, their physical and chemical fundamentals and their main technical characteristics are discussed. This report is intended as a general introduction to a group of reports which summarize the work done on the development and production of the generators, and research on the chemical and physical aspects of the generator systems

  18. Gentc99m, computational system for the technetium-99m generator

    The technetium-99m generator is one of the main products of the PPR, as the continuity of the technetium-99m generator production is important for supporting the development of nuclear medicine. GENTC99M has been made for computational for the technetium-99m generator and includes data processing, documentation and information GENTC99M is also very useful in quality control application especially for the determinations of yield and radionuclidic impurities which consume much time. microsoft visual basic for MS-DOS and visual basic for windows have been used for making GENTC99M. Microsoft visual basic has several features that make it an ideal development language for both MS-DOS and Microsoft Windows. These features not only increase productivity, they also provide all the tools and hooks needed to develop some very sophisticated applications. for a production centre like PPR, GENTC99M is very useful to support the data processing, documentation and information system of the technetium-99m generator and it can also be modified for other products

  19. Imaging prostatitis with Tc-99m ciprofloxacin

    Aim: Tc-99m ciprofloxacin (Infecton) imaging was developed to discriminate infection from inflammation. It claims to show an area of viable, proliferating bacterial population that is actively using DNA gyrase, which the ciprofloxacin inhibits. The application of this imaging has been reported in patients with infected arthroplasty, soft tissue infection, pelvic inflammatory diseases, etc. Clinical evaluation with conventional urological laboratory tests often provides insufficient data in differentiating chronic bacterial prostatitis (CBP) from pelvic pain syndrome, which causes inappropriate or inadequate antibiotic therapy without definite evidence of presence or absence of bacterial infection. Therefore, we investigated the diagnostic value of the Tc-99m ciprofloxacin imaging for CBP by comparing the results of the imaging with those from the conventional tests. Materials and Methods: We custom-formulated a Tc-99m ciprofloxacin kit. We used stannous tartrate for a reducing agent in making the kit. SPECT images of the region of interest were obtained at 3 hours after injection of the radiopharmaceutical. For positive control, we imaged 2 patients: acute prostatitis and urethritis. Then the actual study included 20 subjects. We excluded from the study the patients who had received antibiotic therapy within 6 weeks. The conventional tests included CBC, urinalysis, 4-glass tests, microscopic examination of expressed prostatic secretion, bacterial culture, or PCR for chlamydia trachomatis. Kappa statistics were obtained for comparison of the two tests. Results: By conventional tests, there were 10 subjects with CBP and 10 normal subjects. The typical pattern in the Tc-99m ciprofloxacin imaging indicating CBP was the increased uptake around the prostatic urethra. Five of the 10 subjects with CBP diagnosed by conventional tests showed the increased uptake to be positive cases in the Tc-99m ciprofloxacin imaging. Of the 10 subjects diagnosed as normal by the

  20. Can tumor uptake Tc-99m MDP?

    Objective: To study the distribution of 99mTc-MDP in mice bearing tumor cell lines. Methods: The uptake of 99mTc-MDP was analyzed in seven human tumor cell lines (SPC-Al adenocarcinoma of lung cancer, Bcap-37 breast cancer, T-24 bladder cancer, SKOV3 ovary carcinoma, Hela-229 cervical carcinoma, SCI-OS osteosarcoma, SCI-375 melanoma) and one mouse lung cancer cell line (Lewis). They were transplanted into athymic mice, SCID and C57 mice, respectively. Approximately 10(6) cells of each cell line were injected subcutaneously into a right chest of mouse. After 5-6 weeks, Tc-99m MDP scintigraphy were performed 5-6 hours later after i.v. injection of 74 MBq in 0.05 ml in every mouse. Results:Biodistribution and tumor uptake of MDP was different in the various cell types investigated. Region of interests (ROIs) were placed on a small part of the tumor and a horizontal copied to left chest or spine of mice in Tc-99m MDP imaging. The average count ratio (tumor to contralateral tissue ratio: T/L, tumor to spin ratio: T/N) was calculated. Conclusions: Tumor can uptake Tc-99m MDP including adenocarcinoma. Uptake rate in the central tissue of tumor is higher than other parts of tumor. It may be connected with necrosis calcification of tumor. Tumor or acute myocardial infarction uptake of bone scanning agent may follow the sequence: anoxia-necrosis- calcium and phosphorus ions deposition

  1. Measurement of lymphatic function with technetium-99m-labelled polyclonal immunoglobulin

    A reliable method for measuring lymph flow in physiological units would be valuable, especially in conditions in which it is uncertain whether lymph flow is increased or decreased. The requirements of a radiopharmaceutical for such measurement include stable radionuclide labelling and rapid access to lymphatic vessels following tissue injection but no access to blood vessels. A soluble macromolecule is likely to come closest to meeting these requirements. Technetium-99m- labelled human polyclonal immunoglobulin (HIG) was therefore investigated firstly in comparison with 99mTc-labelled human serum albumin (HSA) in patients undergoing routine lymphoscintigraphy and secondly with respect to injection site in a group of volunteers with post-mastectomy oedema (PMO). Subcutaneous injection of 99mTc-HIG into the web space of a distal extremity gave images in which lymphatic vessels were more clearly defined compared with images obtained after injection of 99mTc-HSA. Lymph nodes were also more clearly defined, suggesting specific retention of HIG, possibly through Fc-mediated binding. Peripheral blood sampling showed a delayed arrival in blood of radioactivity after 99mTc-HIG compared with 99mTc-HSA, although ultimately, the blood recovery of 99mTc-HIG was significantly higher (P 99mTc-HSA. Clearance rates of radioactivity from the injection site were not sinificantly different, however, between the two agents. In patients with PMO, web space injection of 99mTc-HIG gave excellent images of normal lymphatic vessels, of lymph nodes and of abnormal lymph drainage such as dermal backflow in swollen arms. In contrast, neither lymphatic vessels nor lymph nodes were visualised after injection into the skin of the dorsum of the distal forearm. Although there was no difference in clearance rates from the injection sites between normal and swollen arms with either agent in PMO, clearance was significantly faster following injection into the web space (0.11% per minute for normal and

  2. Diagnosis of pulmonary infections with HIV (+) patients. Brought of aerosol DTPA-Tc99m and of Ga67 citrate. Le diagnostic des infections pulmonaires chez les malades VIH (+). Apport de l'aerosol DTPA-Tc99m et du citrate de Ga67

    Banzo, I.; Quirce, R.; Serrano, J.; Jimenez, J.; Tabuenca, O.; Carril, J.M. (Hopital Universitaire Valdecilla, Santander (Spain))

    1993-04-01

    The pulmonary clearance of aerosol DTPA-Tc99m is a technology easy to use, well support by patients with immediate results. With the pneumonia at Pneumocystis Carinii (PPC), the clearance is more sensitive and more specific than the thoracic scintigraphy with Ga67. Used with a thorax radiography, results will lead to three directions: High probability of PPC, di phasic curve and very fast T50, equal inferior to 5,10 mn. Low probability of PPC, monoexponential curve and abnormal thorax radiography or di phasic curve with a value T50 superior to 5,10 mn. With these patients other explorations will be made (Ga67, biopsy) and if possible search pulmonary tuberculosis. Extra pulmonary pathology: monoexponential curve associated with a normal thoracic radiography. 2 figs.

  3. Glomerular filtration rate estimated from the uptake phase of 99mTc-DTPA renography in chronic renal failure

    Petersen, L J; Petersen, J R; Talleruphuus, U;

    1999-01-01

    The purpose of the study was to compare the estimation of glomerular filtration rate (GFR) from 99mTc-DTPA renography with that estimated from the renal clearance of 51Cr-EDTA, creatinine and urea.......The purpose of the study was to compare the estimation of glomerular filtration rate (GFR) from 99mTc-DTPA renography with that estimated from the renal clearance of 51Cr-EDTA, creatinine and urea....

  4. Comparison of inulin, iothalamate, and /sup 99m/Tc-DTPA for measurement of glomerular filtration rate

    Clearances of inulin, 125I-iothalamate, and /sup 99m/Tc-Sn-DTPA were measured simultaneously in five mongrel dogs exhibiting a wide range of glomerular filtration rates (GFR). Standard constant-infusion inulin clearance was compared to radionuclide clearances after subcutaneous injection of the emitters mixed with aqueous epinephrine. All three substances were found to have virtually identical clearances. The accuracy, accessibility, low cost, low radiation hazard, and short half-life of /sup 99m/Tc-Sn-DTPA make it an excellent substance for measuring GFR. The subcutaneous technique offers an accuracy comparable to the more difficult constant-infusion method

  5. Permeability of the bronchial mucosa to /sup 99m/Tc-DTPA in asthma

    Previous investigators, using 99mTc-DTPA aerosol as a marker to assess epithelial permeability in asthma, did not find an increased permeability in this group. However, they either failed to deliver the aerosol to the optimal site (bronchial mucosa, not alveoli) or failed to account for mucociliary clearance in analyzing their results. We studied 10 asthmatics and eight age-matched control subjects using a dosimeter (Spira-Elektra 2) and a carefully controlled breathing pattern to deliver aerosol to the subjects' airways. Two aerosols were delivered on separate days in each patient; 99mTc-DTPA aerosol, and 99mTc-HSA (human serum albumin), using similar breathing patterns to ensure reproducibility of the deposition pattern with the two aerosols. From measurements of retention versus time over a 1-h period, rate constants Ktot and Km were determined for the clearance of 99mTc-DTPA and 99mTc-HSA, respectively. By modelling the airways as a single compartment with two possible routes of clearance, we determined the permeability rate constant, Kp, as Ktot minus Km. There was no significant difference between Ktot in normal subjects and asthmatics; however, because of the slower mucociliary clearance in the asthmatic group, and the relative importance of mucociliary clearance in determining the washout of 99mTc-DTPA aerosol, there was a significant difference in airway permeability between the normal subjects and the asthmatics (t1/2 = 296 min +/- 141 SD and 126 min +/- 58, p less than 0.01, in normal subjects and asthmatics, respectively)

  6. Is the renal uptake of {sup 99m}Tc-DMSA decreased in microalbuminuric diabetic patient?

    Kim, Seong Jang; Kim, In Ju; Kim, Yong Ki [College of Medicine, Pusan National Univ., Pusan (Korea, Republic of)

    1999-08-01

    Diabetic nephropathy is the most common cause of end stage renal disease and the incidence is progressively increasing. The aim of this study was to investigate the differences of {sup 99m}Tc-DMSA renal uptake among diabetic patients with normoalbuminuria, microalbuminuria and overt proteinuria, and then to determine the clinical usefulness of {sup 99m}Tc-DMSA in predicting early diabetic nephropathy. {sup 99m}Tc-DMSA scan was performed and a total renal uptake of {sup 99m}Tc-DMSA was measured in 145 diabetic patients. Patients were divided into 3 groups according to the amount of 24 hour urinary albumin excretion as Group I (normoalbuminuria, 74 cases ), Group II (microalbuminuria, 39 cases), and Group III (overt proteinuria, 32 cases). The differences of {sup 99m}Tc-DMSA renal uptake among the 3 groups and the correlation between the renal uptake of {sup 99m}Tc-DMSA and other clinical parameters were analyzed. The total renal uptake of {sup 99m}Tc-DMSA of Group II (40.8{+-}11.0%) was significantly lower than that of Group I (54.4{+-}6.3%, p<0.001). The uptake of Group III (27.7{+-}12.0%) was significantly lower than those of both Group I and Group II (p<0.001). {sup 99m}Tc-DMSA total renal uptakes correlated negatively with serum creatinine level (r=0.629, p<0.001) and positively correlated with creatinite clearance rate (r=0.702, p<0.001). {sup 99m}Tc-DMSA total renal uptake of diabetic patients with microalbuminuria was significantly decreased compared with that of patients of normoalbuminuria. Therefore, {sup 99m}Tc-DMSA scan can be used as a diagnostic study for early detection of the diabetic nephropathy.

  7. Technetium-99m myocardial imaging agents

    A major focus of cardiovascular radiopharmaceutical research over the past decade has been the search for a Tc-99m agent that could replace Tl-201, the current agent of choice for myocardial perfusion imaging. Recent advances in the inorganic chemistry of technetium, and in the translation of this chemistry to radiopharmaceutical development, make it very likely that this search will soon be successfully completed

  8. Combined Tc-99m sesta MIBI scin

    Enas Abdel Ghany Ibrahim; Momena Essam Elsadawy

    2015-01-01

    Purpose: To evaluate the role of combined high resolution ultrasonography and technetium Tc-99m methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy in preoperative detection and localization of parathyroid adenoma, for better operative outcome. Patients and methods: 40 patients were included in this study, 25 of them were females and 15 were males, with age ranging between 31 and 75 (mean 46 ± 15). All patients presented with some of symptoms of hyperparathyroidism with venous blood ...

  9. Quality control studies and biological evaluation of three locally produced renal pharmaceutical preparations: 99mTc-DTPA, 99mTc-GH and 99mTcDMSA

    Quality control (QC) studies of three locally produced renal preparation of 99mTc-DTPA, 99mTc-GH and 99mTc-DMSA, as a part of the production activity before the Gulf war. The radioanalytical studies were performed using Gel Chromatography column Scanning (GCS) technique, although there are other alternative techniques. These kits tested for radiochemical purity and the labeling yields were found to be excellent. The biological studies included the following parameters; organ distribution (in mice, rats and rabbits), blood clearance in rabbits and plasma protein binding in rats at different time intervals. The poor renal concentration of three agents in mice was significant at two time intervals . The tissue distribution of DTPA, GH and DMSA kits, which were stored at 37 OC for 30 days in mice after intravenous injection of the radioactivity at 5, 30 and 60 minutes. The blood retention of the renal agents was considerably low compared to those in rats and rabbits at the respective time intervals. The blood clearance of 99m'Tc-DMSA was relatively slow and 99mTc-GH has rapid blood clearance identical with that of 99mtc-DTPA for the first 20 minutes but slower thereafter. The binding of DTPA, GH and DMSA with plasma protein was 5, and 95% at 1 hour respectively. Various amounts of tin (11) (as SnCl-2) were used in the kits with up to 10 times more of the usual dose for respective tin-complex and it was observed that there was no significant variation of the usual dose for respective tin-complex and its was observed that there was no significant variation of the organ distribution in mice. (Author)

  10. Evaluation of clinical usefulness of 99mTc-GSA, a functional hepatic imaging agent

    Liver scintigraphy using 99mTc-galactosyl human serum albumin (GSA), which binds specifically to the asialoglycoprotein receptors on the surface of the hepatocytes, was performed in 41 patients with chronic liver disease (11 chronic hepatitis cases and 30 liver cirrhosis cases) to investigate the correlations between the images and the various liver function tests. Two liver functional indexes, HH15 for plasma clearance of 99mTc-GSA and LHL15 for liver accumulation of 99mTc-GSA, showed significant differences between the chronic hepatitis group and the decompensated liver cirrhosis group. These indexes also showed significant correlations with the liver function tests such as serum albumin level and prothrombin time. HH15 and LHL15 correlated with the per-rectal portal shunt index obtained in 10 patients by 99mTcO4- per-rectal portal scintigraphy. These results suggest that HH15 and LHL15 have value as new liver functional indexes. (author)

  11. 99mTc-sestamibi and 99mTc-tetrofosmin scintigraphy in myeloma bone disease

    Full text: Evaluation of the role of scintigraphy with 99mTc-Sestamibi (99mTc-MIBI) and 99mTc-Tetrofosmin (99mTc-TF) in the detection of bone marrow involvement in patients (pts) with multiple myeloma (MM) and in follow-up. 62 pts with MM and 38 pts with monoclonal gammopathy of undetermined significance (MGUS) were enrolled in this study. Forty-seven out sixty-two MM pts had active disease (AD), 10/62 were in complete remission (CR) and 5/62 in partial remission (PR) after chemotherapy. Whole-body scans were obtained 10 min after the i.v. injection of 740 MBq of 99mTc-MIBI in anterior and posterior view. The scans were scored semiquantitatively according to extension and intensity of tracer uptake. All 38 MGUS pts had a negative 99mTc-MIBI scan. As to the MM pts, 49/62 pts (44 with AD, 4 with PR and 1 with CR) had a positive 99mTc-MIBI scan, while the 99mTc-MIBI scan was negative in 13/62 pts (9 with CR, 1 with PR and 3 with AD). The overall sensitivity of the scintigraphic procedure was 92 % while specificity was 97 %. A total of 42 follow-up scans with 99mTc-MIBI were performed in 30 MM pts after high-dose chemotherapy, with an average follow-up duration of 14.6 ± 8.9. The follow-up 99mTc-MIBI scintigraphy was positive in 14/15 of the AD pts, while 6/8 negative scans were observed in the CR pts; the seven PR pts exhibited in five cases a negative scan and in two a mild scintigrafic positivity. The overall sensitivity and specificity of the follow-up scan were, respectively, 86 % and 75 %. In six patients, one at the diagnosis and five showing a positive 99mTc-MIBI scan during the follow-up, 740 MBq of 99mTc-TF was administered within two days with the same acquisition protocol. The scans provided substantially identical information. 99mTc-TF provided a mildly higher contrast between lesion and background activities. The results obtained in this study provide additional evidence indicating that 99mTc-MIBI scintigraphy closely reflects myeloma disease activity in

  12. Can tumor uptake Tc-99m MDP ?

    To explore the mechanism of technetium-99m-methylene diphosphonate (MDP) uptake within tumor through analyze a distribution of Tc-99m MDP in mice bearing tumor cell lines. Methods: The uptake of Tc-99m MDP was analyzed in seven human tumor cell lines ( SPC-A1 adenocarcinoma of lung cancer, Bcap-37 Breast cancer, T-24 Bladder cancer, SKOV3 Ovary carcinoma, Hela-229 Cervical carcinoma, SCI-OS Osteosarcoma, SCI-375 Melanoma) and mouse Lewis lung cancer cell line. They were transplanted into athymic mice, SCID nude mice and C57BL/6 mice, respectively. Approximately 10(6) cells of each cell line were injected subcutaneously into a right chest of mouse. After 4 and 5 weeks, the Tc-99m MDP scintigraphy were determined 6 hours after tail vein injection of 74MBq in 0.05ml every mouse. Result: Biodistribution and tumor uptake MDP was different in the various cell types investigated. According to the Region Ratio program of Siemens Power Macintosh 9500 Computer System, region of interests (RIOs) placed on a small part of the tumor and horizontal copied to left background (T/B) and thoracic spine (T/N) of mice in Tc-99m MDP imaging. The average cpm/pixel ratios were calculated by standardized uptake measure (SUM) and determined the tumor-positive value (T/B) greater than or equal to 1.2. T/B of cell lines were sorted from higher to lower as follows: SCI-OS, Lewis, SKOV3, SCI-375, T-24, SPC-A1, Bcap-37, Hela-229. T/N: SCI-OS, SKOV3, T-24, SCI-375, Lewis, SPC-A1, Bcap-37, Hela-229. The biodistribution data of 99Tcm-MDP in SPC-A1 tumor-bearing BALB/c nude mice were given as ID/g and represent the means D (n=13) in 30 hours after injection of Tc-99m MDP. ID/g of major tissue were sorted from higher to lower as follows: thoracic spine, lumbar, ribs, kidneys, the center of tumor, the ulcer of tumor, the surrounding of tumor, lymph node, blood, lungs, heart, liver. Conclusions: Most of tumor can uptake Tc-99m MDP including human adenocarcinoma. The uptake rate in the center tissue of

  13. Radiosynthesis and biological evaluation of 99mTc-carboxymethylthioethyl iminodiacetic acid as renal imaging agent

    The ligand carboxymethylthioethyl iminodiacetic acid (CMT-IDA), an analogue of nitrilotriacetic acid (NTA) has been radiolabeled with technetium-99m to study its renal clearance and determine its potential as a renal tubular imaging agent. (99mTc(CO)3CMT-IDA)2- could be obtained in >98% radiochemical purity as determined by HPLC. Stability, hydrophilicity and plasma protein binding studies were carried out and were found to be comparable to that of (99mTc(CO)3NTA)2-. Biodistribution studies were carried out in normal Swiss mice at 10 min. p.i. and 2 h.p.i. The complex has shown renal clearance of (71.0±5.9)% ID at 10 min. p.i., which increased to (84.1±10.6)% at 2 h.p.i., with no major uptake in vital organs. (author)

  14. Early detection of amphotericin B induced nephrotoxicity by 99mTc-DTPA: a useful test

    Amphotericin B (AMB) with a broad spectrum of antifungal activity is used for the treatment of life-threatening mycoses, especially in immunocompromised patients. Since measurements of the blood level of AMB and of creatinine do not provide early warning of AMB induced renal toxicity, we studied the effects of AMB on biodistribution of a glomerular agent, 99mTc-DTPA. In Swiss mice, the toxicity of AMB was studied at single intravenous doses of 0.5-3.5 mg/kg body weight. Dose dependent effects consisted of decreased blood clearance and urinary excretion. Recovery of function was shown in dose ranges corresponding to high level clinical schedules. Serum creatinine changes lagged behind the99m Tc-DTPA alterations. This suggests that AMB toxicity might be monitored by blood/urinary clearance of 99mTc-DTPA

  15. Preparation and application of 99mTc-DTPA to renal and vesicoureteral studies

    Dry-kit methods to label DTPA with 99mTc were evaluated. Quality control of 99mTC-DTPA was performed with two gel chromatography methods. The gel chromatography scanning methods was the only method that resulted in a satisfactory separation of the various components. A reproducible high labeling yield of 99mTc-DTPA was found to result. No difference as to the occurrence of vesicoureteral reflux could be established between 99mTc-DTPA and X-ray cystouretherography. Renograms obtained with simultaneously administered 99mTc--DTPA and 131I-Hippuran were compared. The Spearmans correlation coefficients were rs greater than or equal to 0.61 (P less than 0.0005) for normal kidneys. The renogram curves were very similar but not identical in both normal and pathological kidneys. The use of a stochastic modeel and deconvolution enabled renal retention curves to be calculated. The following data were evaluated from the curves: AMPLITUDE of the plateau, MAXIMUM TIME, and MEAN TRASIT TIME. The values obtained with 99mTc-DTPA and 131I-Hippuran correlated well. With both tracers it was possible to distinguish three groups: Normal, parenchymal insufficiency, and ureteral obstruction. Since retention curves express the renal function in its simplest and most explicit form, such curves are easier to interpret than conventional renograms. (author)

  16. Preparation and preclinical pharmacological study on a novel bone imaging agent {sup 99m}Tc-EMIDP

    Lin Jianguo [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Luo Shineng, E-mail: shineng914@yahoo.com.c [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Chen Chuanqing [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Qiu Ling, E-mail: qiulingwx@gmail.co [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Wang Yan [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Cheng Wen; Ye Wanzhong [Key Laboratory of Nuclear Medicine, Ministry of Health and Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063 (China); Xia Yongmei [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China)

    2010-09-15

    A novel zoledronic acid (ZL) derivative, 1-hydroxy-2-(2-ethyl-4-methyl-1H-imidazol-1-yl)ethane-1,1-diyldiphosphonic acid (EMIDP), was prepared and labeled with {sup 99m}Tc successfully in a high labeling yield and good stability in vitro. The preclinical pharmacological properties of {sup 99m}Tc-EMIDP were investigated and compared with {sup 99m}Tc-MDP and {sup 99m}Tc-ZL. The studies of biodistribution in mice and SPECT bone imaging of the rabbit suggest that {sup 99m}Tc-EMIDP has highly selective uptake in the skeletal system and rapid clearance in the soft tissues. The present findings indicate that {sup 99m}Tc-EMIDP holds great potential for bone scintigraphy.

  17. Radionuclides and inflammatory bowel diseases: 99mTc-sucralfate and 111 In-tropolonate-granulocytes

    111In-tropolonate-granulocytes (G-111In) study was performed in 16 patients with inflammatory bowel disease (IBD). Images were obtained 3 h and 20 h post-injection. Counting of four days feacal excretion was more accurately expressed as daily intestinal granulocytes clearance. The day before, 12 of the patients had a sucralfate-99mTc scan (S-99mTc). Correlation between radioendoscopic data and S-99mTc scans was poor in 9 instances and there was no correlation between scan activity index and clinical and biological assessment. Correlation between G-111In scans and radioendoscopic data was excellent in 13 instances. Scan activity index was correlated with the Best index and with the intestinal alpha-1-antitrypsine clearance. Faecal excretion (range. 1 - 40%) and daily intestinal granulocytes clearance values (range. 03 - 50 milliards) were only correlated with protein loss parameters. So S-99mTc scan does not appear to be reliable, while intestinal G-111In clearance, not such easy to perform, can give an accurate assessment of IBD activity

  18. Pharmacokinetics evaluation of Technetium{sup 99m} Ethylene-di-cysteine diethyl ester radiopharmaceutical; Avaliacao farmacocinetica do radiofarmaco etilenodicisteina dietil este'-{sup 99m} Tc (ECD-{sup 99m} Tc)

    Araujo, Elaine Bortoleti de; Carvalho, Olga G. de; Muramoto, Emiko; Almeida, Maria A.T.M. de; Mesquita, Carlos H. de [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1996-07-01

    The biological distribution studies of {sup 99m} Tc-ECD in mice were performed in this work. Using ANACOMP computer program, a composed by seven compatiments was adjusted, characterized by a fast blood clearance, an undirectional renal depuration and intestinal elimination, determined by intense hepato biliary transit. Plasma, bile and urinary samples were analysed by HPLC, showing the in vivo metabolism of the compound. (author)

  19. Technetium-99m pyridoxylideneglutamate (P. G. ) cholescintigraphy

    Stadalnik, R.C.; Matolo, N.M.; Jansholt, A.L.; Krohn, K.A.; DeNardo, G.L.; Wolfman, E.F Jr.

    1976-12-01

    Technetium-99m P.G. cholescintigraphy was performed in 27 human volunteers and 81 patients referred for hepatobiliary tract disease. The gallbladder, biliary system, and gastrointestinal tract were well visualized in the normal patients and volunteers. The gallbladder was not visualized in 22 patients with histologically proved cholecystitis with cystic duct obstruction. Nine patients with complete extrahepatic obstruction of the common bile duct were correctly diagnosed. Hepatocellular disease and incomplete obstruction, with and without jaundice, were diagnosed with this technique. Oral cholecystography is superior to this method for the detection of cholelithiasis in nonjaundiced patients.

  20. Evaluation of acute hepatic injury using 99mTc-Lactosylated serum albumin liver scintigraphy in rats treated with dimethylnitrosamine

    Objective: To assess the feasibility of hepatic asialoglycoprotein receptor scintigraphy using 99mTc-lactosylated human serum albumin (LSA), a newly synthesized radiopharmaceutical with convenient labeling method, in the evaluation. of hepatic functional status, in vivo imaging study with LSA was performed in rats with. acute hepatic injury induced by dimethylnitrosamine (DMN). Results were compared with changes in liver enzyme profiles and histological findings. Methods: DMN (27 mg/kg) was injected i.p. in 20 SD rats to induce acute hepatic injury. Dynamic and static imaging of the chest and abdomen were acquired for 30 minutes after i.v. injection of LSA at the 3rd (DMN-3), 8th (DMN-8), and 21st (DMN-21) days after DMN treatment. Time-activity curves of the heart and the liver were generated from anterior images. Degree of hepatic uptake and blood clearance were evaluated with visual interpretation and semiquantitative analysis using receptor index (LHL3) and index of blood clearance (HH3). Time to maximal binding (Tmax) and slope of the curve (K value) were acquired with maximal likelihood curve fitting method using Prism program. Results: Increases in liver enzymes (AST and ALT) and changes in histological findings (centrilobular necrosis and cellular infiltration) were the most prominent in DMN-3 group, and to a lesser extent after then. Hepatic tracer uptake was lower in DMN-treated rat group. In semiquantitative analysis, LHL3 was significantly lower in DMN-treated rat group than in control group (DMN-3: 0.842, DMN-8: 0.898, DMN-21: 0.91, Control: 0.96, p99mTc-LSA liver scintigraphy could be used in initial evaluation of acute hepatic injury and follow-up studies for recovery. (authors)

  1. In vitro incorporation studies of 99mTc-alendronate sodium at different bone cell lines

    Bisphosphonates can be labeled with Technetium-99m (99mTc) and are used for bone imaging because of their good localization in the skeleton and rapid clearance from soft tissues. Over the last decades bone scintigraphy has been used extensively in the evaluation of oncological patients to provide information about the sites of bone lesions, their prognosis and the effectiveness of therapy by showing the sequential changes in tracer uptake. Since the lesion visualization and lesion/bone ratio are important utilities for a bone scanning radiopharmaceutic; in this study incorporation of 99mTc labeled alendronate sodium (99mTc-ALD) was evaluated in U2OS (human bone osteosarcoma) and NCI-H209 (human bone carcinoma) cell lines. ALD was directly labeled by 99mTc, radiochemical purity and stability of the complex were analyzed by radioactive thin layer chromatography and radioactive high performance liquid chromatography studies. For cell incorporation study, NCI-H209 and U2OS cell lines were used with standard cell culture methods. The six well plates were used for all experiments and the integrity of each cell monolayer was checked by measuring its transepithelial electrical resistance (TEER) with an epithelial voltammeter. Results confirmed that ALD was successfully radiolabeled with 99mTc. 99mTc-ALD incorporated with NCI-H209 and U2OS cells. The uptake percentages of 99mTc-ALD in NCI-H209 and U2OS cell lines were found significantly different. Since 99mTc-ALD highly uptake in cancer cell line, the results demonstrated that radiolabeled ALD may be a promising agent for bone cancer diagnosis. (author)

  2. 99mTc labeled VIP analog: evaluation for imaging colorectal cancer

    Early and reliable diagnosis of colorectal cancer continues to be demanding and challenging. Colorectal cancer cells express Vasoactive Intestinal Peptide (VIP) receptors in high density. We have prepared a VIP analog (TP3654), labeled it with 99mTc, and evaluated it in experimental animals as an agent for imaging colorectal cancer. The tissue distribution of 99mTc-TP3654 has been compared with that of 111In-DTPA-Octreotide and 99mTc-anti-CEA scan in nude mice bearing human colorectal cancer LS174T. Finally, pharmacokinetic and tissue distribution studies of 99mTc-TP3654 have been performed in four normal human volunteers. Data suggest that 99mTc-TP3654 can be prepared efficiently without loss of its receptor specificity and biological activity. Although the 24 hr tumor uptake of 99mTc-TP3654 in the animal model used was modest (0.21 ± 0.07% I.D./g), the tissue distribution profile was more favorable than that of 111In-DTPA-Octreotide or 99mTc-anti-CEA scan. Human studies indicated that 99mTc-TP3654 had no adverse effect in any subject. Within 24 hours, approximately 70% of the injected dose cleared through the kidneys, and approximately 20% through the hepatobiliary system. In these non-fasting volunteers hepatobiliary clearance was slow and in cancer patients tumor uptake was rapid. Data suggest that 99mTc-TP3654 is a promising agent for imaging colorectal cancer

  3. Possible role of 99mTc-Dextran (99mTc-Dx) in detection of occult small intestinal lesions

    Two cases are presented wherein 99mTc-dextran (99mTc-Dx) imaging localised focal pathology in the small intestine and contributed in reaching a preoperative diagnosis. In the first case, 99mTc-pertechnetate and 99mTc-Dx accumulated in a suspected Meckel's diverticulum equally well. 99mTc-Dx additionally identified exudative discharge from the lesion. In the second case, 99mTc-Dx identified a distal ileal lesion later proved to be a non-specific ulcer on surgery. 99mTc-Dx scanning may have a role in imaging of occult intestinal lesions. (author)

  4. Tc-99m erythromycin lactobionate inhalation scintigraphy in parenchymal lung diseases

    Durak, Hatice E-mail: hdurak@kordon.deu.edu.tr; Aktogu, Serir; Degirmenci, Berna; Sayit, Elvan; Ertay, Tuerkan; Dereli, Sevket

    1999-08-01

    We have investigated Technetium 99m erythromycin lactobionate (Tc 99m EL) clearance from the lungs after inhalation, in the presence of an alveolitis. Eighteen patients (6 sarcoidosis, 7 idiopathic fibrosis, and 5 miliary tuberculosis) were imaged after the patients inhaled 1,110 MBq of Tc 99m EL. Clearance half time for the first 45 min, for 24 h, and retention at 24 h correlated with percentage of lymphocytes in bronchoalveolar lavage fluid (BAL) (r=.729, r=.883, and r=.826, respectively). There was a positive correlation between peripheral penetration (PP) and forced expiratory volume in 1 s (FEV{sub 1}) (r=.806) and forced vital capacity (FVC) (r=.781). Retention was more marked in sarcoidosis compared with tuberculosis (0.02599m EL may be related to number of BAL cells or presence of a lymphocytic alveolitis. Long residency time of Tc 99m EL in the lungs implies that erythromycin can also be administered by inhalation for therapeutic purposes.

  5. Tc-99m erythromycin lactobionate inhalation scintigraphy in parenchymal lung diseases

    We have investigated Technetium 99m erythromycin lactobionate (Tc 99m EL) clearance from the lungs after inhalation, in the presence of an alveolitis. Eighteen patients (6 sarcoidosis, 7 idiopathic fibrosis, and 5 miliary tuberculosis) were imaged after the patients inhaled 1,110 MBq of Tc 99m EL. Clearance half time for the first 45 min, for 24 h, and retention at 24 h correlated with percentage of lymphocytes in bronchoalveolar lavage fluid (BAL) (r=.729, r=.883, and r=.826, respectively). There was a positive correlation between peripheral penetration (PP) and forced expiratory volume in 1 s (FEV1) (r=.806) and forced vital capacity (FVC) (r=.781). Retention was more marked in sarcoidosis compared with tuberculosis (0.025< p≤0.05). Radioaerosol lung imaging may reflect the pulmonary function impairment in parenchymal lung diseases. Retention of Tc 99m EL may be related to number of BAL cells or presence of a lymphocytic alveolitis. Long residency time of Tc 99m EL in the lungs implies that erythromycin can also be administered by inhalation for therapeutic purposes

  6. Bioavailability of {sup 99m}Tc-paclitaxel-glucuronide ({sup 99m}Tc-PAC-G)

    Biber Muftuler, F.Z.; Demir, I.; Uenack, P.; Ichedef, C.; Yurt Kilcar, A. [Ege Univ., Izmir (Turkey). Dept. of Nuclear Applications

    2011-07-01

    An antitumor agent paclitaxel (PAC) has been proved to be efficient in the treatment of breast and ovarian cancer. Glucuronic acid-derived paclitaxel compound (paclitaxel-glucuronide (PAC-G)) was enzymatically synthesized using microsome preparate separated from rat livers. The biodistribution mechanism of PAC-G in healthy female Albino Wistar rats has been investigated. The expected structure is confirmed according to LC/MS results, and the possible attachment is to C2-hydroxyl group. PAC-G was labeled with {sup 99m}Tc and the radiochemical yield of radiolabeled compound ({sup 99m}Tc-PAC-G) was 98.0 {+-} 02.74% (n=9). The range of the breast/blood and breast/muscle ratios is approximately between 3 and 35 in 240 min. All these experimental studies indicate that {sup 99m}Tc-PAC-G may potentially be used in breast tissue as an imaging agent. (orig.)

  7. Tc- 99 m gel generator; an alternative source of Tc-99 m for medical uses

    Tc-99 m is widespread radioisotope in nuclear medicine and it can be produced by two different methods. The first method is performed by chromatographic genera tory by using Mo-99 prepared by fission of U-235, and another method is activation of Mo-99 can be complexed by ZrOCl2 and produce a gel. Mo-99 remains in this gel and Tc-99 m elute with normal saline solution. Many factors such as P H, concentration of Mo in the gel structure, and drying conditions of gel affect on the efficiency of the generator. In this research the gel generator production and some factors which are effecting on the 99 m Tc production are presented

  8. Phase II clinical study on sup 99m Tc-GSA, a new agent for functional imaging of the liver

    Torizuka, Kanji (Fukui Medical School (Japan)); Ha-Kawa, S.K.; Kudo, Masatoshi; Kitagawa, Shinichi; Kubota, Yoshitsugu; Tanaka, Yoshimasa; Hino, Megumu; Ikekubo, Katsuji

    1992-01-01

    Phase II study of {sup 99m}Tc-DTPA-galactosyl human serum albumin ({sup 99m}Tc-GSA), a new radiopharmaceutical which binds to the asialoglycoprotein receptors on the hepatocytes, was performed in 81 patients with liver diseases to validate its safety and possibility for the evaluation of hepatic function. None of adverse reactions, abnormal clinical laboratory findings and anti-{sup 99m}Tc-GSA antibody production due to {sup 99m}Tc-GSA was recognized. Immediately after the injection of {sup 99m}Tc-GSA, the dynamic data and serial hepatic images were obtained for 60 min. The indices for blood clearance and liver accumulation were calculated based on the counts in the regions of interest on the hearts and livers. In 54 patients with chronic hepatic disorders such as liver cirrhosis, the blood clearance and liver accumulation of {sup 99m}Tc-GSA were retarded according to the progress of the hepatic disorders. The findings of {sup 99m}Tc-GSA scintigraphy also reflected the hepatic functions of the patients with large hepatic tumors, obstructive jaundice and acute hepatitis. These results suggest that {sup 99m}Tc-GSA has the clinical potentials to evaluate the liver functions in the patients with hepatic disorders. (author).

  9. The single-plasma-sample method for determining the glomerular filtration rate with Tc-99m-diethylenetriamine pentaacetic acid in childhood and adolescence. Is it age-dependent?

    The aim of this study is to assess the accuracy of the pre-existing single-plasma-sample method (SPSM) to measure the glomerular filtration rate (GFR) with Tc-99m-diethylenetriamine pentaacetic acid (Tc-99m-DTPA) in children and adolescents. In addition, the age-independent SPSM is evaluated with two algorithms (Bubeck and Russell) applied for Tc-99m-mercaptoacetyltriglycine (Tc-99m-MAG3) SPSM. The study was performed on 14 patients (12 men and 2 women; age range 3 to 19 yr) with renal diseases. Tc-99m-DTPA (5 MBq/kg) was injected intravenously and thereafter blood samples were taken at 5, 15, 60, 90, 120, 150 and 180 min via the indwelling tube. Radioactivity in the injection syringe and plasma was measured by means of a double-well single-plastic scintillation counter. The true'' GFR as a reference was determined by two methods: 2-exponential curve fitting 7 samples (GFR7) and 1-exponential curve fitting 3 samples between 90 and 150 min (GFR3) in a slow clearance phase. The GFR7 and GFR3 were searched for to the clearance (GFR1) estimated from a plasma concentration at various sample times by means of 3 equations designed for children (Groth and Aasted, Ham-I and -II) and 3 for adults (Christensen and Groth, Jacobsson, Itoh). All the SPSM showed close correlations (r>0.95) with the reference methods. Among them, Jacobsson's equation at sample time=120 min tended to be the most accurate (r=0.9826, root mean squared error (RMSE)=7.8 ml/min)). On the other hand, Ham-I's equation at sample time=120 min was the most accurate, when it was referred to GFR3 in correction for overestimation (r=0.9951, RMSE=4.60 ml/min). The Bubeck and Russells' algorithms showed that the regression equation between the GFR7 and the estimates was different in 2 groups of adults (49 cases) and children/adolescents. Our study indicates that Jacobsson's and Christensen and Groth's equations designed for adults are also applicable in determining the GFR with Tc-99m-DTPA in children and

  10. /sup 99m/Tc(Sn)-N-pyridoxylaminates: a new series of hepatobiliary imaging agents

    Three derivatives of N-pyridoxylamino acid were synthesized: /sup 99m/Tc(Sn)-N-pyridoxylphenylalanine, -N-pyridoxyltryptophan, and -N-pyridoxyl-5-methyltryptophan. The chemical and biologic properties of each complex was found to be quite analogous to those of the corresponding /sup 99m/Tc(Sn)pyridoxylideneaminate. In rats, /sup 99m/Tc(Sn)-N-pyridoxyl-5-methyltryptophan [/sup 99m/Tc(Sn)PHMT] showed rapid blood clearance, fast hepatobiliary transit, low urinary excretion, and no intestinal reabsorption. Over 90% of the dose arrived in the intestine through the liver at 30 min after i.v. administration, whereas only 2% of the dose escaped through the kidneys. In rabbits the gallbladder was clearly visualized within 5 min of injection and no renal or bladder images were noted on any scintiphotos. The BSP (sulfobromophthalein) intervention study revealed that the biliary excretion of /sup 99m/Tc(Sn)PHMT is much more resistant than that of /sup 99m/Tc(Sn) diethyl-IDA to the intervention of BSP and hence to serum bilirubin. Toxicity studies on PHMT and Sn-PHMT indicated a wide margin of safety for the proposed human dose

  11. Effects of radiofrequency ablation on individual renal function: assessment by technetium-99m mercaptoacetyltriglycine renal scintigraphy.

    Nasu,Yasutomo

    2006-04-01

    Full Text Available We quantitatively evaluated total and individual renal function by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3 renal scintigraphy before and after radiofrequency ablation (RFA of renal tumors. Eleven patients who underwent Tc-99m MAG3 renal scintigraphy 1 week before and after RFA were evaluated (7 men and 4 women ; age range : 23-83 years ; mean age : 60.6 years. Five patients had solitary kidneys, and five had normally or minimally functioning contralateral kidneys. One patient had a renal cell carcinoma in the contralateral kidney. One patient with a solitary kidney underwent RFA a second time for a residual tumor. In patients with a solitary kidney, MAG3 clearance decreased after 5 of 6 RFAs, and in patients with a normally functioning contralateral kidney, MAG3 clearance decreased after 4 of 5 RFAs, but no significant differences were observed between before and after treatments. In addition to the total MAG3 clearance, the split MAG3 clearance was evaluated in patients with a normally functioning contralateral kidney. MAG3 clearance decreased in 4 of 5 treated kidneys, while it adversely increased in the contralateral kidneys after 4 of 5 RFAs. No significant differences, however, were observed between before and after treatments. The results of our study revealed no significant differences in sCr, BUN, CCr, or MAG3 clearance between pre- and post-RFA values. These results support data regarding the functional impact and safety of renal RFA in published reports. We evaluated total and individual renal function quantitatively using Tc-99m MAG3 renal scintigraphy before and after treatment. This scintigraphy was very useful in assessing the effects of RFA on renal function.

  12. Tagging fatty acids with 99m tecnetium

    In a search for a fatty acid analogue suitable for labelling with sup(99m)Tc for myocardial imaging, analogues of the general formula X-Y-COOH where the ligand groups X, Y were NH2, SH or COOH, capable of forming complexes with metal ions, were synthesized. Among many such, one compound (CH2(SH).CH2(SH).(CH2)8.COOH) was selected for further study. Injected intravenously together with a reducing agent into mice, rats and one dog, the compound proved unsatisfactory for the purpose because of its toxicity and its failure to localize in the myocardium. The search for alternative analogues and alternative labelling procedures must continue

  13. Diagnosis of Caroli's disease by technetium-99m DISIDA cholescintigraphy. Report of three cases

    Three patients in whom Caroli's disease was diagnosed by cholangiographic methods were studied by scintigraphy with Tc-99m DISIDA. Cholescintigrams showed an intense concentration of the radionuclide in the form of round spots near the hepatic hilus in late images. In two patients with cholestasis, a delayed hepatic clearance of the radionuclide was observed, which improved when the exploration was performed after a choledocoduodenostomy. Tc-99m DISIDA is not only a good noninvasive method to diagnose Caroli's disease, but also a useful technique to evaluate the patency of the biliary tree during the follow-up of such patients

  14. Dose estimation of Tc-99m-DTPA-galactosyl-human serum albumin (Tc-99m-GSA) in the blood with nonlinear regression method

    Tc-99m-DTPA-galactosyl-human serum albumin (Tc-99m-GSA) was applied as an agent for receptor-binding hepatic scintigraphy. A single dose of 3-10 mg/185 MBq (5 mCi) Tc-99m-GSA per body was administered in four healthy volunteers and three patients. Time-activity curves for 60 (40) min after injection were obtained from the regions-of-interest over the heart and lung (background). Exponential regression curve was generated from the heart curve during 2-60 (40) min after background subtraction with nonlinear least squares method. Regression curve was well fitted to the heart curve and a significant correlation coefficient of 0.997±0.003 was obtained between these two curves. Absolute dose of GSA in the blood was decided on the assumption that extrapolated value of regression curve at time 0 represented the total injected dose. The absolute dose differences between sample blood and regression curve were 1.4-4.3% (mean). Nonlinear regression analysis is useful for estimating quantitative dose of GSA in blood without any blood samples. (author)

  15. Quantitative analysis by digital computer of 99mTc-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatogram in diffuse parenchymal liver diseases

    99mTc-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatograms were analyzed to provide information about the liver and bile duct. Calculations were based on a four compartmental model and included corrections for blood, tissue, hepatic parenchymal and bile backgrounds. The time activity curves for 99mTc-PMT in the cardiac region were described as the sum of two exponential functions, while curves for the hepatic regions were described as the sum of three exponential components. The measured hepatograms were compared with simulations and good agreement between the two curves showed that the compartmental model adequately described the blood and bile activities in vivo. Hepatic excretion rate constants were 0.179 ± 0.026 in three normal subjects, 0.102 ± 0.012 in four patients with chronic hepatitis and 0.082 ± 0.034 in six patients with liver cirrhosis. In the case of diffuse parenchymal liver disease, there were lower rate constants for the excretion from the liver to the bile ducts than in normals, and the relative distribution volumes were also larger than normal. Prior to the development of this compartmental model, no useful kinetic model had been found which could satisfactorily explain the time activity curves. Experience in human studies proves this method to be accurate in determining the rate constants for the hepatobiliary transport of 99mTc-PMT. (orig.)

  16. Quantitative analysis by digital computer of Tc-99m N-pyridoxyl-5-methyltryptophan (Tc-99m PMT) hepatogram in diffuse parenchymal liver diseases

    Tc-99m N-pyridoxyl-5 methyltryptophan (Tc-99m PMT) hepatograms were analyzed to provide information about the liver and bile duct. Calculations were based on a 4 compartmental model and included corrections for blood, tissue, liver and bile backgrounds. The time-activity curves for Tc-99m PMT in the cardiac region were described as the sum of 2 exponential functions, while curves for the hepatic region were described as the sum of 3 exponential components. The measured hepatograms were compared with simulated hepatograms and good agreement between the two curves showed that the compartmental model adequately described the blood and bile activities in vivo. Hepatic excretion rates were 0.179 +- 0.028 in 3 normal subjects. 0.102 +- 0.012 in 4 patients of chronic hepatitis and 0.116 +- 0.061 in 6 patients of liver cirrhosis. In the cases of diffuse parenchyal liver diseases, there were lower rate constants for the excretion from the liver to the bile ducts than in normals and the relative distribution values also larger than normal. Prior to the development of this compartmental model, no useful kinetic model had been found which could satisfactorily explain the time-activity curves. Experience in human studies proves this method to be accurate in determining the rate constants for hepatobiliary transport of Tc-99m PMT

  17. Biokinetics and dosimetry in patients of {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesin: images of GRP receptors; Biocinetica y dosimetria en humanos de {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesina: imagenes de receptores GRP

    Santos C, C. L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2007-07-01

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [{sup 99m}Tc]EDDA/HYNIC-Lys{sup 3}-bombesin ({sup 99m}Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red

  18. Process modifications of obtaining Tc-99m by solvent extraction

    This paper describes a modification in the process to obtaining Tc-99m by the extraction method of solvent from Mo-99 produced by irradiation. Tc-99m is considered an ideal radionuclide for medical and biological applications

  19. Biokinetics and dosimetry in patients of {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide prepared from lyophilized kits

    Gonzalez-Vazquez, Armando [Departamento de Medicina Nuclear, Hospital Militar (Mexico); Facultad de Medicina, Universidad Autonoma del Estado de Mexico (Mexico); Ferro-Flores, Guillermina [Departamento de Materiales Radiactivos, Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico, C.P. 52045 (Mexico)]. E-mail: gff@nuclear.inin.mx; Arteaga de Murphy, Consuelo [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran (Mexico); Gutierrez-Garcia, Zohar [Departamento de Medicina Nuclear, Hospital Militar (Mexico)

    2006-07-15

    {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide ({sup 99m}Tc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for {sup 99m}Tc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3{+-}0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv.

  20. Internal dose assessment of 99mTc-HTOC

    Full text: Octreotide is a synthetic octapeptide analog of somatostatin. Its major effects inhibit the release of pituitary growth hormone and the endocrine secretions of the pancreas, stomach, and intestine. So it is recommended to control symptoms associated with neuroendocrine tumours. In therapy, it is necessary to estimate patient-specific absorbed dose, especially to dose-limiting risk organs and to the tumour tissue. Kinetic analyses need to be carefully planned, meanwhile absorbed fraction are most similar to the subject in question should be chosen. However, the result of dose assessment is not sufficiently accurate or detailed to guide clinical decision-making, and not well correlated with observed effects on patient's organs and tumours. In this study, 99mTc-HTOC is an excellent indicator that displays the distribution of 188Re- HTOC in patient's body. The kinetic information of 99mTc -HTOC in patient's body can be obtained by SPECT in 1,4 h after injection. The activity in patient's tumours and organs can be calculated by lined the time-activity curve. In the study, the data of 86 cases can be collected. Although the basic formula of dose assessment is based on that of the medical internal radiation dose committee (MIRD), the absorbed fractions have been adjusted to be more patient-specific by patient's CT image and other data. It make internal dose of patients more accurate by the method. (author)

  1. Evaluation of the absorbed dose to the kidneys due to Tc99m (DTPA) / Tc99m (Mag3) and Tc99m (Dmsa)

    The absorbed dose in the kidneys of adult patients has been assessed using the biokinetics of radiopharmaceuticals containing Tc99m (DTPA) / Tc99m (Mag3) or Tc99m (Dmsa).The absorbed dose was calculated using the formalism MIRD and the Cristy-Eckerman representation for the kidneys. The absorbed dose to the kidneys due to Tc99m (DTPA) / Tc99m (Mag3), are given by 0.00466 mGy.MBq-1 / 0.00339 mGy.MBq-1. Approximately 21.2% of the absorbed dose is due to the bladder (content) and the remaining tissue, included in biokinetics of Tc99m (DTPA) / Tc99m (Mag3). The absorbed dose to the kidneys due to Tc99m (Dmsa) is 0.17881 mGy.MBq-1. Here, 1.7% of the absorbed dose is due to the bladder, spleen, liver and the remaining tissue, included in biokinetics of Tc99m (Dmsa). (Author)

  2. Technetium 99 m spiperone dithiocarbamate study as a potential agent for brain pathologies diagnosis related to D 2 dopamine receptors

    Psycho-pharmacology has been discovering much about the D 2 dopamine receptors and their interrelationship to brain pathologies such as Parkinson's Disease, Schizophrenia and Huntington Disease. Those biological receptors have got affinity with dopamine endogenous agent, so that they complex and, in non pathological individuals, the biological receptors contribute to bring the levels of dopamine and free acetylcholine into equilibrium. The D 2 antagonistic psychotropic agents because of having got strong affinity with those receptors, have been being transformed into radiopharmaceuticals to diagnose these pathological disease of Central Nervous System. The Spiperone Dithiocarbamate complex studied by us, is a potential diagnosis agent because of being highly lipo-soluble and having close relationship with D 2 receptors. Besides, it is a photon emitter, allowing the use of SPECT (Single Photon Emission Computed Tomography) technique which is economically less expensive if compared to the PET (Positron Emission Tomography) technique. The Spiperone Dithiocarbamate (SPDC) is synthesized from Spiperone and its complexation with Technetium-99 m has been prepared with its reaction parameters after being studied and improved. The SPDC-99m Tc complex biological distribution have made in Wistar rats and the uptake of spleen, heart, liver stomach, lung, kidney, blood, intestine and brain have been resolved. The plasmatic clearance curve has been based on Wistar rats data and the know-how of the kit (for label SPDC with Tc) has been achieved. (author). 5 figs, 4 tabs

  3. Biokinetics and dosimetry in patients of 99mTc-HYNIC-Lys3-Bombesin: images of GRP receptors

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [99mTc]EDDA/HYNIC-Lys3-bombesin (99mTc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using 99mTc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after 99mTc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99mTc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. 99mTc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red marrow). The mean effective dose was 3

  4. Quantitative analysis of 99mTc-GSA liver scintigraphy with graphical plot method

    99mTc-galactosyl human serum albumin (99mTc-GSA) is a newly developed receptor-binding agent, specific for the asialoglycoprotein receptor, which resides exclusively on the plasma membrane of mammalian hepatocytes. Liver scintigraphy using 99mTc-GSA was performed on 65 patients with liver diseases. Dynamic data were obtained by gamma camera during 20 minutes after the intravenous injection of 3 mg (185 MBq) of 99mTc-GSA. The maximum removal rate of 99mTc-GSA (denoted as P (2)) was measured by two methods: nonlinear five-compartment model analysis adopting the Michaelis-Menten constant for the transfer of 99mTc-GSA from hepatic blood to receptor, and a graphical plot using compartmental dose curves. The graphical plot could estimate easily the maximum removal rate in terms of two data points of 0 and 1 minutes without nonlinear least squares and numerical integration. The results indicated that the maximum removal rate was decided immediately after the intravenous injection of 99mTc-GSA. Although 99mTc-GSA is recognized to accumulate nonlinearly on the liver, the rate constant P (2)* (1/min) of transfer from hepatic blood to the receptor was estimated by graphical plot, assuming a linear five-compartment model. P (2)* Km, which was given by the product of the rate constant P (2)* and the Michaelis constant Km, was well correlated with P (2). Next, for 99mTc-GSA liver scintigraphy, we applied a Patlak plot that was applicable to the linear system, and the rate constant Ku of transfer from extrahepatic blood to the liver was estimated. From the results of graphical plot, it was theoretically shown that Ku represented P (2). This was confirmed by clinical data. (author)

  5. Mismatched uptake of Tc-99m-ECD and Tc-99m-HMPAO in subacute cerebral infarction: Tc-99m-ECD for viability and Tc-99m-HMPAO for flow restoration

    Lee, D. S.; Hyun, I. Y.; Kim, S. K. [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)] [and others

    1997-07-01

    Tc-99m-HMPAO reflects tissue perfusion but Tc-99m-ECD uptake is affected by tissue viability in addition to tissue perfusion which the varied state of cellular retention of Tc-99m-ECD reflects. Luxuriously perfused area on Tc-99m-HMPAO SPECT implies that this cortex was already reperfused either spontaneously or after thrombolysis and that accompanied paralysis of vascular reactivity in those zones warms progressive deterioration. We tried to find out if we can use sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT to reveal cortical perfusion and severity and range of risky areas of cerbral cortex despite reperfusion in sub-acute infarction. In 13 patients (M ; F =7 : 6, mean age 57 (range: 26-84)) with cortical (n=12) and basal ganglia infarction (1), we performed sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT at the same position. At first, 555 MBq of Tc-99m-ECD was injected and imaged and then 1110 MBq of Tc-99m-HMPAO was injected again and imaged with the patients in situ, and the first image (Tc-99m-ECD) and the subtracted image (2nd- 1st : Tc-99m-HMPAO) were compared slice by slice. Study was done from 3 days to 31 days (16{+-}9) after ictus. Tc-99m-ECD uptake was always less than or equal to Tc-99m-HMPAO uptake at the lesion in all cases. Luxury perfusion was prominent in four patients. Mismatched uptake was found in 10 patients. Severity of mismatch showed diverse spectrum and was ranged from total middle cerebral artery territory (1 case) to peripheral thin zones around infarction (2 cases). The other 7 showed intermediate amount of tissues with mismatch , i.e., Tc-99m-ECD defects where Tc-99m-HMPAO uptake is in part increased, normal or decreased. Upon discharge, patients having more uptake with Tc-99m-ECD predicted improvement. Patients having mismatched uptake went dichotomous way. In conclusion, Tc-99m-ECD/Tc-99m-HMPAO sequential SPECT is feasible and reveal both tissue perfusion (Tc-99m-HMPAO ) and discrepant Tc-99m-ECD uptake probably reflecting viability in acute

  6. Mismatched uptake of Tc-99m-ECD and Tc-99m-HMPAO in subacute cerebral infarction: Tc-99m-ECD for viability and Tc-99m-HMPAO for flow restoration

    Tc-99m-HMPAO reflects tissue perfusion but Tc-99m-ECD uptake is affected by tissue viability in addition to tissue perfusion which the varied state of cellular retention of Tc-99m-ECD reflects. Luxuriously perfused area on Tc-99m-HMPAO SPECT implies that this cortex was already reperfused either spontaneously or after thrombolysis and that accompanied paralysis of vascular reactivity in those zones warms progressive deterioration. We tried to find out if we can use sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT to reveal cortical perfusion and severity and range of risky areas of cerbral cortex despite reperfusion in sub-acute infarction. In 13 patients (M ; F =7 : 6, mean age 57 (range: 26-84)) with cortical (n=12) and basal ganglia infarction (1), we performed sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT at the same position. At first, 555 MBq of Tc-99m-ECD was injected and imaged and then 1110 MBq of Tc-99m-HMPAO was injected again and imaged with the patients in situ, and the first image (Tc-99m-ECD) and the subtracted image (2nd- 1st : Tc-99m-HMPAO) were compared slice by slice. Study was done from 3 days to 31 days (16±9) after ictus. Tc-99m-ECD uptake was always less than or equal to Tc-99m-HMPAO uptake at the lesion in all cases. Luxury perfusion was prominent in four patients. Mismatched uptake was found in 10 patients. Severity of mismatch showed diverse spectrum and was ranged from total middle cerebral artery territory (1 case) to peripheral thin zones around infarction (2 cases). The other 7 showed intermediate amount of tissues with mismatch , i.e., Tc-99m-ECD defects where Tc-99m-HMPAO uptake is in part increased, normal or decreased. Upon discharge, patients having more uptake with Tc-99m-ECD predicted improvement. Patients having mismatched uptake went dichotomous way. In conclusion, Tc-99m-ECD/Tc-99m-HMPAO sequential SPECT is feasible and reveal both tissue perfusion (Tc-99m-HMPAO ) and discrepant Tc-99m-ECD uptake probably reflecting viability in acute or

  7. Preparation and biodistribution in mice of 99mTc-DTPA-b-cyanocobalamin

    Cyanocobalamin (CNCbl), a kind of vitamin B12 (cobalamin, Cbl), which has a special binding capability to rapid dividing cells and proliferating tissue, especially tumors, has been modified and labeled by 99mTc. The optimal labeling condition was determined, and the biodistribution of 99mTc-DTPA-b-CNCbl both in normal mice and TA2 mice bearing MA891 mammary tumors were studied. 99mTc-DTPA-b-CNCbl showed low uptake and rapid clearance in nontarget tissues, and renal excretion. About 40% of uptake at 1 hour remained in the tumor at 12 hours p.i. The satisfying ratio of T/NT was acquired at 6 hours p.i. (author)

  8. 99mTc radiolabeling and biodistribution study of scorpionfish (Scorpaena plumieri) venom in Swiss mice

    The use of radiotracers in research of animal venom has been scarce, although it allows an excellent approach to follow the process of biodistribution and kinetics of toxins, and tissue distribution studies are very important for clinical use. Our group has demonstrated that Scorpaena plumieri venom (SP) possess high antitumoral activity and can be a source of template molecules for the development of antitumoral drugs. The purpose of this study was to radiolabel SP with 99mTc and investigate its biodistribution profile. High labeling yield was obtained and the results suggest that [99mTc]SP can be an useful tool for in vivo studies. The analysis indicated that SP is excreted manly by the kidneys with a slow clearance rate. The significant [99mTc]SP uptake in the heart and lungs may explain, at least partially, the pulmonary edema and effect cardiac observed by the envenoming. (author)

  9. Liver scintigraphy in biliary atresia using 99mTc-GSA

    Liver Scintigraphy using 99mTc-DTPA-galactosyl-human serum albumin is a modern diagnostic tool that can be used to evaluate postoperative liver function in patients with biliary atresia. Calculating the HH15 (Clearance index) and LHL15 (receptor index) indicates the hepatic functional reserve. We evaluated 11 patients with biliary atresia using liver scintigraphy to assess the chronological changes in liver function postoperatively. Results were compared with laboratory data HH15 and LHL15 obtained by liver scintigraphy using 99mTc-GSA improved after portoenterostomy, however, no correlation with laboratory data could be found. Even preoperative results were within the normal range for adults suggesting that the normal range of HH15 and LHL15 in children must differ from the adult range. The present study suggests that 99mTc-GSA scintigraphy will be able to assess the hepatic functional reserve which can not be detected by various other conventional liver function tests. (author)

  10. Renal imaging with a new agent sup(99m)Tc-d1-DMS

    By using sup(99m)-Tc-d1 DMS labeled with 99 m-Tc using stannous chloride and prepared with freeze-dried d1-DMS containing a 3:1 molar ratio of DMS and Sn+2 the effect of stereochemical factor of DMS on kidney affinity, renal images, blood clearance, urinary excretion was studied in experimental animals and two normal volunteers and 75 patients. The comparation revealed a quite similar formation of complex II from d1-DMS to that from the meso-form, judge from its absorption spectra and absorption behavior into the gel. The stereochemical difference of DMS is not a critical factor for the formation of the sup(99m)-Tc-DMS complex with high affinity for the kidney, although it is believed that the renal accumulation of Tc-complex will depend greatly on chemical configuration of the complex. (APR)

  11. The behavior of 99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) in blood and brain

    99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) is a reagent for scanning cerebral blood flow. We investigated how 99mTc-HMPAO changed in the blood and brain. The 99mTc-HMPAO, which was prepared by adding of 99mTcO4- to HMPAO and Sn(II), consisted of primary and secondary complexes, reduced hydrolyzed 99mTc, and 99mTc-pertechnetate. The percentage of the primary complex in 99mTc-HMPAO decreased with time after preparation. The primary complex converted to the secondary one very rapidly in the presence of plasma. When 99mTc-HMPAO was injected into patients, 99mTc activity was immediately partitioned in the plasma fraction, with approximately 60% in whole blood. In plasma, 99mTc was found to be associated with proteins such as albumin and globulin. 99mTc trapped in red cells was not washed out with either plasma or saline. Biodistribution studies showed that the less lipophilic compounds of 99mTc-HMPAO could not pass through the blood brain barrier (BBB), and therefore did not accumulate in the brain. The results of gel chromatography and equilibrium dialysis indicated that no specific 99mTc binding protein was present in the brain. Considering the instability of 99mTc-HMPAO in vivo, we proposed that the speed at which the primary complex converted to the less lipophilic compounds was important in allowing 99mTc-HMPAO to pass through the BBB and to be fixed in the brain. (orig.)

  12. Water-pipe smoking effects on pulmonary permeability using technetium-99m DTPA inhalation scintigraphy

    Although extensive work has been done on cigarette smoking and its effects on pulmonary function, there are limited number of studies on water-pipe smoking. The effects of water-pipe smoking on health are not widely investigated. The aim of this study was to determine the effects of water-pipe smoking on pulmonary permeability. Technetium-99m DTPA inhalation scintigraphy was performed on 14 water-pipe smoker volunteers (all men, mean age 53.7±9.8) and 11 passive smoker volunteers (1 woman, 10 men, mean age 43.8±12). Clearance half-time (T 1/2) was calculated by placing a monoexponential fit on the time activity curves. Penetration index (PI) of the radioaerosol was also calculated. PI was 0.58±0.14 and 0.50±0.12 for water-pipe smokers (WPS) and passive smokers (PS) respectively. T 1/2 of peripheral lung was 57.3±12.7 and 64.6±13.2 min, central airways was 55.8±23.5 and 80.1±35.2 min for WPS and PS, respectively (p≤0.05). Forced expiratory volume in one second/forced vital capacity (FEV1/FVC)% was 82.1±8.5 (%) and 87.7±6.5 (%) for WPS and PS, respectively (0.025< p≤0.05). We suggest that water-pipe smoking effects pulmonary epithelial permeability more than passive smoking. Increased central mucociliary clearance in water-pipe smoking may be due to preserved humidity of the airway tracts. (author)

  13. Technetium-99m-dimethylglyoxime ([sup 99m]Tc-DMG) as renal imaging agent

    Adonaylo, V.N. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Buenos Aires Univ. (Argentina). Dept. de Ciencias Biologicas); Stahl, Adriana; Pomilio, A.B.; Vitale, A.A. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales); Canellas, C.O. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1993-06-01

    Dimethylglyoxime (DMG) labelled with [sup 99m]Tc is presented as a renal imaging agent. The behaviour of this complex was analysed at different pH by means of UV spectral data and using DMG-calcium chloride as a reference complex. Biokinetic data were evaluated in two biological models, Sprague-Dawley rats and Didelphis albiventris argentine opossum. Biodistribution in rats demonstrated fast and specific renal excretion. Time-activity values over both kidneys could be quantified for this complex. Renographic studies led to mean time-to maximum values on twelve assays of 2.0 [+-] 0.1 min and a mean relative function of 53.0 [+-] 2.3 and 47.0 [+-] 3.2 for right and left kidneys, respectively. [sup 99m]Tc-DMG showed specificity for the renal excretion pathway and therefore seems to be a very useful radiopharmaceutical for renal function studies. (Author).

  14. Technetium-99m-dimethylglyoxime (99mTc-DMG) as renal imaging agent

    Dimethylglyoxime (DMG) labelled with 99mTc is presented as a renal imaging agent. The behaviour of this complex was analysed at different pH by means of UV spectral data and using DMG-calcium chloride as a reference complex. Biokinetic data were evaluated in two biological models, Sprague-Dawley rats and Didelphis albiventris argentine opossum. Biodistribution in rats demonstrated fast and specific renal excretion. Time-activity values over both kidneys could be quantified for this complex. Renographic studies led to mean time-to maximum values on twelve assays of 2.0 ± 0.1 min and a mean relative function of 53.0 ± 2.3 and 47.0 ± 3.2 for right and left kidneys, respectively. 99mTc-DMG showed specificity for the renal excretion pathway and therefore seems to be a very useful radiopharmaceutical for renal function studies. (Author)

  15. Kinetic investigations of sup(99m)Tc-labelled radiopharmaceuticals

    Several radiopharmaceuticals (sup(99m)Tc-Fe-ascorbates, sup(99m)Tc-Sn-DTPA, sup(99m)Tc-Sn-ACD-citrate-complex and sup(99m)Tc-Sn-tetracyclin-HAsc-ACD-complex) for renal and tumour scintigraphy were tested in animal experiments. Also tested was sup(99m)Tc-penicillamine for scintigraphic investigations of the gallbladder and the liver. The findings suggest that the different radiopharmaceuticals have different degrees of reliability and exactness, and that some of them should be combined to achieve better diagnostic values. (GSE/AK)

  16. Tc 99m-infecton and Tc99m-HiG in evaluation of patients with pulmonary tuberculosis

    The m of the present study is to clarify the role of Tc99m-HIG and Tc99m-infecton in assessment of patients with pulmonary TB. Thirty-four patients with pulmonary tuberculosis proved by X-ray, bronchial lavage, sputum analysis and culture were included in the study. Tc99m-infecton and Tc99m-HIG were given intravenous in a dose of 740 MBq (20 md) with imaging after 1 and 4 hours. Images were correlated with clinical, radiological and laboratory data. Tc99m-infecton and Tc99m-HIG showed true positive results in 30 and 24 patients and false negative study in 4 and 10 patients, respectively. The sensitivity of Tc99m-infecton was 88% whereas that of Tc99m-HIG was 70%. When eighteen patients were followed up for 8 months after therapy with anti-tuberculous therapy, sixteen of them showed conversion of mycobacterium culture to negative. Tc99m-infecton images were true negative in 12 of them (specificity 75%) while only 8 of them were true negative on Tc99m-HIG study (specificity 50%) and only 6 were true negative on chest X-ray (specificity 37.5%). It can be concluded that Tc99m-infecton is more sensitive than Tc99m-HIG in diagnosis and monitoring response to treatment of pulmonary tuberculosis

  17. Technetium-99m Radiopharmaceuticals for Monitoring Drug Resistance. Chapter 12

    Resistance to chemotherapy constitutes a major obstacle to cancer cures. Cellular mechanisms of resistance involve efflux pumps, P-glycoprotein (Pgp), the product of the MDR1 gene and the related membrane glycoprotein, multidrug resistance associated protein 1 (MRP1). Multidrug resistant cell lines overexpressing Pgp are resistant to a structurally and functionally diverse group of chemotherapeutic agents. Many of these drugs tend to be lipophilic and positively charged at neutral pH. This suggested the application of the two lipophilic cationic 99mTc radiopharmaceuticals currently used for myocardial perfusion, 99mTc-MIBI and 99mTc-Tetrofosmin. Efforts were also made to develop specific 99mTc labelled substrates for Pgp based on lipophilic cationic 99mTc complexes. A large number of studies indicated that 99mTc-MIBI, 99mTc-Tetrofosmin and some related 99mTc compounds are substrates for Pgp. However, it remains uncertain whether these 99mTc labelled compounds are substrates for MRP1. Thus, both 99mTc-MIBI and 99mTc-Tetrofosmin would be general probes of transporter mediated multidrug resistance in tumour cells. (author)

  18. Tc-99m p-aminohippuric acid renal scintigraphy: results of preliminary animal and human studies

    Purpose: Tc-99m p-aminohippuric acid (PAH) is a new radiopharmaceutical labeled with Tc-99m in presence of calcium three sodium salt of DTPA by use of Sn(II) - reduction method. Tc-99m PAH is rapidly secreted by the kidneys in a manner consistent with tubular secretion, as confirmed by rat probenecid studies. The present study aimed at evaluating Tc-99m PAH as renal imaging agent. Methods: After bolus injection of radiopharmaceutical in a Wister rat (17 MBq) and in 10 healthy subjects - 2 normal volunteers and 8 potential kidney. donors (111 MBq) dynamic images were acquired for 20 min in three frame groups. In all patients Tc-99m MAG3 and Tc-99m DTPA studies were also performed several days later, in l day intervals to acquire renal studies for comparison. The scintigraphic images and time/activity curves were analyzed. Results: Rat study gave typical three-phase renogram and satisfactory renal functional images with no significant extrarenal background. During Tc-99m PAH scintigraphy in humans rapid disappearance of radiopharmaceutical from the vascular system and high uptake in kidneys followed by its very fast elimination and low residual activity at the end of the study were registered. Anterior whole body images obtained at 40 min and 3 h post injection to evaluate the distribution of 99mTc-PAH within the body showed neither gallbladder nor liver activity. Mean values of the following semi-quantitative parameters were calculated; time to peak (Tmax): 3.65±0.91, time from peak to 50% of peak activity (T1/2): 6.91±2.71, percentage of residual activity in each kidney at the end of the study: 26±2.71 and split renal function: 51.26±3.92. Mean values of Tmax and T1/2 obtained with Tc-99m PAH were significantly lower in comparison with Tc-99m DTPA. Mean values of relative function did not show any significant difference between three tracers. Conclusion: Our preliminary results confirmed good biological characteristics of 99mTc-PAH, indicating its potential

  19. Preparation and preliminary evaluation of {sup 99m}Tc-EC-For-MLFK

    Verbeke, K.; Verbeke, A.; Vanbilloen, H.; Verbruggen, A. E-mail: alfons.verbruggen@uz.kuleuven.ac.be

    2002-07-01

    For-Met-Leu-Phe-Lys (For-MLFK), a chemotactic peptide that binds with high affinity to granulocytes and monocytes, was labeled with {sup 99m}Tc using ethylene dicysteine (EC) as the metal chelating system. EC was selected because of the rapid renal excretion of its {sup 99m}Tc-complex and therefore, was expected to enhance the degree of urinary elimination of the peptide-conjugate. {sup 99m}Tc-EC-For-MLFK was prepared using a preformed chelate approach. After incubation of {sup 99m}Tc-EC-For-MLFK with total blood, 68.1% of the labeled peptide was associated with WBC and 86% of this cell-associated activity was bound to granulocytes. Biodistribution studies in normal mice revealed a very fast blood clearance (4.1% and 0.6% of I.D. in blood at respectively 5 and 60 min p.i.). However, elimination of the labeled peptide proceeds mainly via the hepatobiliary system (24.5% of I.D. in liver and 48.8% of I.D. in intestines at 60 min p.i.) and to a much lower degree via the kidneys (17.9% in renal system at 60 min p.i.). From these results, it is concluded that {sup 99m}Tc-EC-For-MLFK is not suited to image infections, despite its high binding to granulocytes, since it leads to high, non-specific, abdominal activity.

  20. Accumulation of Tc-99m-MIBI and Tc-99m-tetrofosmin in tumor cells. Uptake and washout studies

    Aim: To investigate in-vitro the uptake and washout of Tc-99m-MIBI and Tc-99m-tetrofosmin in human breast adenocarcinoma and soft tissue sarcoma cell lines. Methods: The uptake of Tc-99m-MIBI and Tc-99m-tetrofosmin (at 370C, 10, 30 and 60 minutes after incubation with 7.4x10E5 Bq each tracer) was investigated in breast adenocarcinoma MCF-7 and SK-BR-3 cells, synovial sarcoma SW 982 cells and chondrosarcoma SW 1353 cells (concentration of 1x10E6 cells/ml incubation medium). Tracer uptake in cells incubated with ouabain (Na/K-ATPase pump inhibitor; 100 μM and 1mM; 15 and 30 minutes), nigericin (increases mitochondrial potential and disrupts cell membrane potential; 5 and 50 μg/ml; 15 minutes) and carbonyl cyanide m-chlorophenylhydrazone (CCCP) (depolarizes mitochondrial membrane; 10 and 100 μM; 30 minutes) was compared to that in cells without incubation with chemical agents (control cells). The washout (at 370C, 10-60 minutes, 30 and 60 minutes after tracer incubation) of Tc-99m-MIBI and Tc-99m-tetrofosmin was studied in MCF-7 cells, SK-BR-3 cells , SW 1353 cells and fibrosarcoma SW 684 cells. Results: Cellular tracer uptake decreased with ouabain (decrease of Tc-99m-tetrofosmin > Tc-99m-MIBI in SK-BR-3 cells and SW 982 cells) and increased with nigericin (increase of Tc-99m-MIBI > Tc-99m-tetrofosmin in all cells) as compared to the uptake in control cells. With CCCP, decrease of Tc-99m-MIBI uptake in cells preincubated with nigericin was higher than that in cells under basal conditions, whereas a similar decrease of Tc-99m-tetrofosmin uptake in these two group of cells was found. Washout of Tc-99m-MIBI from all cells was lower than that of Tc-99m-tetrofosmin. No significant difference in cell-associated activity of both tracers was found between washout after 30 minutes and that after 60 minutes of incubation, in all cells. Washout of Tc-99m-MIBI from SK-BR-3 cells Tc-99m-tetrofosmin) and Na/K-ATPase pump (Tc-99m-tetrofosmin > Tc-99m-MIBI). Tc-99m-MIBI and Tc-99

  1. Kinetics of radiolabelled (99mTc) heparin and low molecular weight heparin fractions CY 216, CY 222 in patients with uncomplicated myocardial infarction

    Kinetics of plasmatic disappearance of 99mTc-heparin and low molecular weight heparin (LMWH) fractions CY 216 and CY 222 were compared in 2 women and 8 men (aged 50-71) with uncomplicated myocardial infarction. The three technetiated heparins were consecutively injected intravenously (67 nanomoles) to each of 10 patients, at intervals of 3-5 days, 14-28 days after acute cardiac onset. The plasma radioactivity was counted in blood samples collected within a period of 5 h. 99mTc-heparin and LMWH fractions CY 216, CY 222 disappeared from plasma following a biexponential clearance curve with a fast and slow component reflecting the biodistribution (α) and elimination (β) phase. The bioavailability values as well as distribution and elimination rates were similar for all three technetiated heparins. The bulk of injected 99mTc-heparin or LMWH fraction was rapidly distributed to the tissue compartment, whereas the radiocomplex remaining in the circulation was slowly eliminated with a half-time of an average 320 min. Radioactivity eliminated from plasma was only partially (30-50%) excreted in the urine. The results indicate that after a low-dose intravenous administration LMWH fractions CY 216 and CY 222 maintain the pharmacokinetic properties of standard heparin, especially the rapid distribution to the tissue compartment. (author)

  2. Pharmacokinetics evaluation of Technetium99m Ethylene-di-cysteine diethyl ester radiopharmaceutical

    The biological distribution studies of 99m Tc-ECD in mice were performed in this work. Using ANACOMP computer program, a composed by seven compatiments was adjusted, characterized by a fast blood clearance, an undirectional renal depuration and intestinal elimination, determined by intense hepato biliary transit. Plasma, bile and urinary samples were analysed by HPLC, showing the in vivo metabolism of the compound. (author)

  3. Standardization of a method to calculate absolute renal uptake of {sup 99m} Tc-DMSA in children; Padronizacao do metodo para calculo da captacao renal absoluta do {sup 99m}Tc-DMSA em criancas

    Ono, Carla Rachel; Sapienza, Marcelo Tatit; Watanabe, Tomoco; Costa, Paulo Luiz Aguirre; Okamoto, Miriam Roseli Yoshie; Garcez, Alexandre Teles; Buchpiguel, Carlos Alberto [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Servico de Medicina Nuclear]. E-mail: crachelo@usp.br; Machado, Beatriz Marcondes; Machado, Marcia Melo Campos [Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital Universitario; Liberato Junior, Waldyr de Paula

    2006-01-15

    Objective:To standardize a method and determine normal values for absolute renal uptake of 99m Tc-DMSA in children with normal creatinine clearance. Materials and methods: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years) without clinical evidence of renal disease were studied using 99m Tc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99m Tc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance. Absolute renal uptake of 99m Tc-DMSA (DMSA-Abs) was expressed as the fraction of the administered dose retained by each kidney six hours after administration of the radiopharmaceutical. Results: DMSA-Abs was 21.8 +- 3.2% for the right kidney and 23.1 +-3.3% for the left kidney. There was no correlation between renal uptake and the age groups studied, although there was a tendency to an increase in the creatinine clearance with age. Conclusion: Normal values of DMSA-Abs can be used as an additional parameter for the initial diagnostic evaluation and during follow-up of renal diseases, mainly when bilateral impairment of renal function is suspected or in a patient with a single functioning kidney (in which renal differential function is of limited value). (author)

  4. Evaluation of myocardial perfusion using Tc-99m MIBI

    Tc-99m MIBI (methoxy isobutyl isonitrile) is newly introduced cationic myocardial perfusion agent. For its favorable dosimetry, upto 30 mCi of Tc-99m MIBI can be used in a patient. Therefore, unlike T1-201, first-pass ejection fraction, ventricular wall motion, and SPECT studies are readily evaluated using Tc-99m MIBI on patients who are undergoing myocardial perfusion study. Nineteen individuals entered into this study and 9 of 19 had T1-201 myocardial scintiscan. For the detection of myocardial ischemia, an IV dipyridamole with hand-grip or bicycle exercise was used. Tc-99m MIBI scintigraphic findings are compared to patients 'EKG' T1-201 scans and coronary angiograms. The result were summerized as follows; 1. In 9 cases, Tc-99m MIBI studies were comparable to T1-201 scintiscans. 2. In the remaining 10 cases, Tc-99m MIBI images were correlated well with clinical pictures, EKG, and angiographic findings. 3. Using Tc-99m MIBI, one can easily obtain fist-pass ejection fraction, ventricular wall motion and SPECT studies. It was concluded that Tc-99m MIBI seems to be an excellent agent for myocardial perfusion study. Tc-99m MIBI images are superior in quality than T1-201 images mainly due to high photon yield and ideal energy of Tc-99m MIBI

  5. Retention of 99mTc-DMSA(III) and 99mTc-nanocolloid in different syringes affects imaging quality.

    Bauwens, Matthias; Pooters, Ivo; van der Pol, Jochen; Mottaghy, Felix M; van Kroonenburgh, Marinus

    2014-04-01

    (99m)Tc-dimercaptosuccinic acid [DMSA(III)] and colloidal human serum albumin ((99m)Tc-nanocolloid) are widely used radiopharmaceuticals. Recently, in our institution we encountered image quality problems in DMSA scans after changing the brand of syringes we were using, which triggered us to look into the adsorption properties of syringes from different brands for (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid. We also describe a clinical case in which adsorption of (99m)Tc-DMSA(III) caused inferior imaging quality. DMSA and nanocolloid were labeled with (99m)Tc following manufacturer guidelines. After synthesis, syringes with (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid were stored for 15, 30, 60, and 120 min. We evaluated Luer Lock syringes manufactured by different brands such as Artsana, Henke-Sass-Wolf, B. Braun Medical N.V., CODAN Medizinische Geräte GmbH & Co KG, Becton Dickinson and Company, and Terumo Europe. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid was acceptably low for all syringes (brands with (99m)Tc-DMSA(III) adsorption rates of 36 and 30%, respectively, and for one brand with a (99m)Tc-nanocolloid adsorption rate of 27%. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid reaches critical levels in syringes produced by two brands, potentially causing poor image quality--for example, in DMSA scans using pediatric radiopharmaceutical doses. It is advised to check the compatibility of any radiopharmaceutical with syringes as an integral part of the quality assurance program. PMID:24569706

  6. Measurement of split glomerular filtration rate by fractional renal uptake of Tc-99m DTPA

    The percent renal uptake of Tc-99m DTPA, within 2 to 3 minutes following the radionuclide appearance into the kidneys according to the method by Gates, was correlated well with the sodium thiosulfate clearance determination (n = 75, r = 0.846) as well as the 24-hour creatinine clearance determination (n = 47, r = 0.893). Therefore, the formula for calculation of glomerular filtration rate (GFR) was derived from the linear regression analysis between renal uptake of Tc-99m DTPA and sodium thiosulfate clearance determination, accordingly: GFR (ml/min.) = 8.775 x (% total renal uptake) + 9.685. In the 31 patients without nephrouropathy, the split GFR of left kidney was 53.6 +- 10.9 ml/min. and that of right kidney was 52.0 +- 11.1 ml/min. The radionuclide computed GFR was also examined for the evaluation of split function of renal parenchyma, in comparison with Tc-99m DTPA renogram pattern. In most cases with standard renogram pattern, the split GFR showed the values over 35 ml/min. Most cases with hypofunctioning renogram pattern showed the values of split GFR within the range of 20-35 ml/min. And most cases with nonfunctioning renogram pattern showed the values under 20 ml/min. In the present study, the split GFR determination was found to be a useful and reliable method for the quantitative evaluation of split function of renal parenchyma. (author)

  7. Preoperative evaluation of hepatic functional reserve following hepatectomy by technetium-99m galactosyl human serum albumin liver scintigraphy and computed tomography

    It is extremely important to have a good grasp of the acceptable limit of hepatectomy before operation because postoperative liver failure can take a fatal course; however, baseline data on the limit of hepatectomy have not been clearly defined. We therefore evaluated and compared the predicted remnant liver function obtained by computed tomography(CT) and technetium-99m diethylenetriamine penta-acetic acid-galactosyl human serum albumin (99mTc-GSA) liver scintigraphy in order to obtain precise data regarding remnant liver function before hepatectomy. We investigated 20 patients undergoing hepatectomy using the clearance rate of indocyanine green (KICG) as a parameter, and compared the predicted postoperative KICG obtained by CT and by transaxial single-photon emission tomographic (SPET) images acquired by 99mTc GSA liver scintigraphy before hepatectomy. In GSA studies, based on time-activity curves for the heart and liver, we compared HH15 (heart activity at 15 min divided by heart activity at 3 min), LHL15 (liver activcity at 15 min divided by heart plus liver activity at 15 min) and KL (obtained from the time-activity curve for the liver) in 103 patients. In 58 patients without increased serum bilirubin, KL was compared with KICG. In four patients, occlusion of the right portal vein was performed with the aim of carrying out secondary hepatectomy, and changes in liver volume were compared between CT and 99mTc GSA liver scintigraphy. The correlation coefficient between the postoperative KICG predicted by CT and the actual postoperative KICG was rather poor, at r = 0.569 (P99mTc GSA liver scintigraphy and the actual postoperative KICG was good, at r = 0.788 (PL and HH15 and between KL and LHL15 in 103 patients were very good or good, at r = 0.906 (PL and KICG in 58 patients was very good, at r = 0.916 (P99mTc GSA liver scintigraphy is useful for predicting remnant liver function before hepatectomy and for evaluating changes in regional liver function after

  8. External monitoring of kidney transplant function using Tc-99m(Sn)DTPA

    The purpose of this study was to evaluate the use of an external counting technique to provide daily monitoring of kidney transplant function by measuring the renal clearance of Tc-99m(Sn)DTPA. During the first few weeks following transplant, 15 patients had their renal clearance of Tc-99m DTPA measured daily over periods of 5-24 hr. Clearance rates were compared with daily plasma creatinine levels, and the effects of diurnal variation, drug treatment, and physical activity noted. The results show that any significant fall in clearance rate of chelate, indicating a rejection episode, preceded a rise in plasma creatinine levels by at least 24 hr. One episode of transplant failure presented as a sudden deterioration in clearance rate of chelate; in the others the change was more gradual but was still apparent within hours. It is considered that this noninvasive, low-dose, easy-to-perform technique is of considerable value in extended daily monitoring of renal function and is superior to standard daily or twice-weekly renography for the early detection of transplant rejection

  9. {sup 99m}Tc-interleukin-2 and {sup 99m}Tc-HMPAO granulocyte scintigraphy in patients with inactive Crohn's disease

    Annovazzi, Alessio; Chianelli, Marco; Capriotti, Gabriela; Signore, Alberto [Nuclear Medicine Unit, Department of Clinical Sciences, Policlinico Umberto I, University ' ' La Sapienza' ' , 00161, Rome (Italy); Biancone, Livia; Pallone, Francesco [Gastroenterology Unit, University ' ' Tor Vergata' ' , Rome (Italy); Caviglia, Renato [Gastroenterology Unit, University ' ' Campus Biomedico' ' , Rome (Italy); Mather, Stephen J. [Department of Nuclear Medicine, St Bartholomew' s Hospital, Cancer Research UK, London (United Kingdom); Caprilli, Renzo [Gastroenterology Unit, Department of Clinical Sciences, University ' ' La Sapienza' ' , Rome (Italy); Scopinaro, Francesco [Department of Radiological Sciences, University ' ' La Sapienza' ' , Rome (Italy)

    2003-03-01

    .91, respectively) but a weak positive predictive value (0.44 and 0.39, respectively). Nevertheless, Kaplan-Meier curves generated between scintigraphic findings and time free from disease relapse were statistically different only for {sup 99m}Tc-IL2 scintigraphy (log-rank test, P=0.013). These results indicate that {sup 99m}Tc-IL2 scintigraphy can be useful in selecting CD patients in clinical remission who could benefit from preventive therapy to avoid disease relapse. (orig.)

  10. Deconvolution analysis of 99mTc-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) dynamic SPECT imaging

    Hepatic transfer function was obtained by deconvolution analysis using dynamic SPECT data of 99mTc-N-pyridoxyl-5-methyl-tryptophan. Minimum, mean and maximum transit times were evaluated from transfer function. Total and regional effective hepatic blood flow (EHBF) was estimated from the uptake constant with single blood sampling. Functional images of minimum, mean and maximum transit times and regional EHBF were constructed. In 12 cases of liver cirrhosis and 8 cases of normal controls, it was shown that there is a good correlation between the total EHBF obtained by the uptake constant and that measured by blood clearance (r=0.96). In cases of liver cirrhosis, averaged total EHBF was markedly decreased (645±162 ml, mean±SD, p<0.001) and averaged mean transit time was significantly prolonged (23.7±3.9 min, p<0.05) as compared with those in normal controls (1382±232 ml, 20.1±2.2 min, respectively). Total EHBF and regional EHBF negatively correlated with the mean transit time (r=-0.52, r=-0.70, respectively). There were a few cases with liver cirrhosis which showed normal transit time and regional EHBF despite marked liver atrophy and decreased total EHBF. This method is thought to be highly valuable in evaluating regional and total liver functions and pathophysiology of diffuse liver diseases. (author)

  11. Standardization of a method to calculate absolute renal uptake of 99m Tc-DMSA in children

    Objective:To standardize a method and determine normal values for absolute renal uptake of 99m Tc-DMSA in children with normal creatinine clearance. Materials and methods: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years) without clinical evidence of renal disease were studied using 99m Tc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99m Tc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance. Absolute renal uptake of 99m Tc-DMSA (DMSA-Abs) was expressed as the fraction of the administered dose retained by each kidney six hours after administration of the radiopharmaceutical. Results: DMSA-Abs was 21.8 +- 3.2% for the right kidney and 23.1 +-3.3% for the left kidney. There was no correlation between renal uptake and the age groups studied, although there was a tendency to an increase in the creatinine clearance with age. Conclusion: Normal values of DMSA-Abs can be used as an additional parameter for the initial diagnostic evaluation and during follow-up of renal diseases, mainly when bilateral impairment of renal function is suspected or in a patient with a single functioning kidney (in which renal differential function is of limited value). (author)

  12. Sup(99m)Tc compounds for diagnostic purposes

    The applications of sup(99m)Tc in nuclear medicine are discussed, such as sodium pertechnetate in thyroid and brain scintigraphy, complex compounds in lungs and liver diao.nosis. Technetium generators are classified according to the method of separating sup(99m)Tc from 99Mo. Adsorption generators are used, molybdate-99 is adsorbed on an Al2O3-packed column while pertechnetate-99m is eluted with 0.9% NaCl solution. Also used is continuous pertechnetate-99m extraction with methyl ethyl ketone from 0.5 M potassium molybdate and 2.5 M of potassium carbonate. The manufacture is described of kits for sup(99m)Tc radiopharmaceuticals preparation, eg., Diagos I, a gluconate complex, a lyophilisate for sup(99m)Tc-sodium pyrophosphate injections, a diagnostic kit for lung scintiscanning. (H.S.)

  13. Novel 99mTc labeled

    FAN; Caiyun

    2006-01-01

    ,Nucl.Med.Biol.,2003,30:273-284.[33]John,C.S.,Lim,B.B.,Geyer,B.C.Et al.,99mTc-labeled σ-receptor-binding complex:Synthesis,characterization,and specific binding to human ductal breast carcinoma (T47D) cells,Bioconj.Chem.,1997,8:304-309.[34]Choi,S-R.,Yang,B.,P(o)ssl,K.Et al.,Development of a Tc-99m labeled sigma-2 receptor-specific ligand as a potential breast tumor imaging agent,Nucl.Med.Biol.,2001,28:657-666.[35]Zhang,Y.,Williams,W.,Torrence-Campbell,C.et al.,Characterization of novel N,N′-disubstituted piperazines as sigma receptor ligands,J.Med.Chem.,1998,41:4950-4957.[36]Maeda,D.N.,Williams,W.,Kim,W.E.et al.,N-arylalkylpi-peridines as high-affinuty sigma-1 and sigma-2 receptor ligands:Phenylpropylamine as potential leads for selective sigma-2 agents,Bioorg.Med.Chem.Lett.,2002,12:497-500.[37]Moore,T.S.,Boyle,M.,Thorn,V.M.et al.,N-substituted derivatives of piperazine and ethylenediamine,Part Ⅰ.The preparation of N-monosubstituted derivatives,J.Chem.Soc.,1929:39.[38]Stewart,H.W.,Turner,R.J.,Denton,J.J.et al.,Experimental chemotherapy of filariasis,Ⅳ.The preparation of derivatives of piperazine,J.Org.Chem.,1948,13:134-143.[39]O'Neil,J.P.,Wilson,S.R.,Katzenellenbogen,J.A.,Preparation and structural characterization of monoamine-monoamide bis(thio) oxo complexes of technetium(V) and rhenium(V),Inorg.Chem.,1994,33:319-323.[40]Bowen,W.D.,Sigma receptors:Recent advances and new clinical potentials,Pharm.Acta Helv.,2000,74:211-218.[41]Deuther-Conrad,W.,Patt,J.T.,Feuerbach,D.et al.,Norchloro-fluoro-homoepibatidine:Specificity to neuronal nicotinic acetylcholine receptor subtypes in vitro,IL Farmaco,2004,59:785-792.[42]Vilner,B.J.,Bowen,W.D.,Modulation of cellular calcium by sigma-2 receptors:Release form intracellular stores in human SK-N-SH neuroblastoma cells,J.Pharmacol.Exp.Ther.,2000,292:900-911.[43]Cheng,Y.,Prusoff,W.H.,Relationship between the inhibition constant (Ki) and the concentration of inhibitor which cause 50% inhibition (IC50) of an enzymatic reaction

  14. Studies of labelling of melphalan with technetium-99m

    Melphalan is an alkylating agent widely used in the treatment of neoplastic diseases. However, being an α-amino acid it cannot be labeled with Tc-99m by the use of SnCl2 for pertechnetate reduction. The N-carboxy methyl - derivative of melphalan was obtained and its complexing by technetium-99m was examined. A procedure for labelling of melphalan derivative with Tc-99m has been developed. (author). 18 refs, 8 figs, 8 tabs

  15. Role of 99mTc-mercaptoacetyltriglycine, a new radiopharmaceutical, in the diagnosis of diseases of the kidneys and urinary tract in children

    Using the method of dynamic scintigraphy of the kidneys with a new radiopharmaceutical preparation, 99mTc-mercaptoacetyltriglycine. 35 children with various urological and nephrological diseases were examined. In indicated cases the examination was supplemented with administration of a diuretic, with further projections or indirect mictional cystography. The standard parameters of functional curves and their standard extent were assessed in a group of 18 healthy kidneys. No significant difference was found as compared with results obtained using 131I-hippuran. The assessed values of global clearance attained 66% of the 131I-hippuran clearance values. In 60% of the patients the visualization of the parenchyma and in 80% the visualization of the efferent urinary pathways was better than when 99mTc-DTPA was used. In all instances the scintigrams were better than when 131I-hippuran was used. The new radiopharmaceutical combines the advantages of technetium-labelled preparations and the favorable pharmacokinetic properties of hippuran. It is suitable for quantification of tubular secretion. It is superior to hitherto used substances as regards the quality of visualization and in particular the lower radiation load. Therefore it is especially suited for pediatric practice. (author). 2 tabs., 4 figs., 13 refs

  16. Imaging bone infection using Tc-99m infecton: case studies

    Tc-99m infecton (ciprofloxacin) was introduced recently as an infection imaging agent which is specific for bacteria. If successful, this may prove superior to labelled leucocyte imaging, antibodies and other nonspecific agents in terms of logistics, cost and efficacy. We had recently acquired few kits for Tc-99m infecton preparation. Our preliminary experience suggests that it has high specificity for the infected bone and may be useful in bone tuberculosis. Three cases are presented where both Tc-99m MDP scanning and Tc-99m infecton study were undertaken to highlight the potential of this new agent. (author)

  17. 99mTc-ciprofloxacin for diagnosis of bacterial infection

    Aungurarat, A.; Ngamprayad, T.; Dangprasert, M.; Phumkem, S.; Jowanaridhi, B.

    2015-05-01

    Preparation of 99mTc-ciprofloxacin for diagnosis of bacterial infection was investigated by varying factors which affected this compound. The optimum conditions for preparation of 99mTc-ciprofloxacin and a lyophilized kit for Tc-99m labelling were studied. The results from biodistribution study showed that the percentages of the injected dose per gram tissues of infected area at 1 and 3 hours after injection were around 0.25-0.56. 99mTc-ciprofloxacin was found sterile, pyrogen-free and non-toxic. Radiochemical purity was greater than 90% with greater than 6 hours of stability.

  18. Evaluation of usefulness of 99mTc-GSA liver scintigraphy in postoperative biliary atresia patients

    Liver scintigraphy was performed using a newly developed radiopharmaceutical, 99mTc-DTPA-galactosyl-human serum albumin (99mTc-GSA), in 17 patients after hepatic portenterostomy for biliary atresia (age: 3 months-14 years old, body weight: 5.8-39 kg). These patients were divided into two groups; good hepatic function group was 3 cases which had no symptom after operation, and poor hepatic function group was 14 cases which needed some therapeutic procedures for ascending cholangitis, GI tract bleeding etc. Dynamic data were obtained by a gamma camera during 20 minutes after intravenous injection of 1.5-3.0 mg (92.5-185 MBq) of 99mTc-GSA. The livers were clearly delineated in all cases. We calculated HH15 (clearance index) for the index of clearance and LHL15 (receptor index) for the index of hepatic uptake. In good hepatic function group, HH15 was 0.396±0.059 (mean±S.D.), LHL15 was 0.960±0.009. In poor hepatic function group, HH15 was 0.629±0.080, LHL15 was 0.875±0.060. The difference between the mean value of both indices was statistically significant. Using single photon emission CT, inhomogenisity of liver accumulation of 99mTc-GSA was clarified, and focal hepatocyte damage, which could not be detected on CT, was able to be estimated. We consider that 99mTc-GSA liver scintigraphy is a useful study for continuous observation of the patients with biliary atresia. (author)

  19. Development and evaluation of a single vial cold kit for infection imaging: Tc-99m Ciprofloxacin

    Radiolabeled antibiotics have been used in nuclear medicine for the diagnosis of bacterial infection. They are used as specific infection-imaging agents because of their affinity to bind with bacteria. Tc-99m Ciprofloxacin is the most widely used infection-imaging agent. The aim of the present work is to increase the shelf life of an in house developed single vial kit for the preparation of Tc-99m Ciprofloxacin. Different methods were used to make the Ciprofloxacin kits. Kits were stored at a temperature of 4 deg. C under nitrogen atmosphere and evaluated for stability by serially estimating the labeling efficiency using instant thin layer chromatography (ITLC) following reconstitution with Tc99m pertechnetate at regular intervals of time up to 90 days after their preparation. The data were subjected to Sigmaplotsoftware version 8.0 for shelf-life analysis. The kits were further evaluated for a number of standard quality control parameters. Kits containing sodium chloride-Ciprofloxacin pellets were found to have a shelf life of 7 months and constantly maintaining a labeling efficiency of 95% Tc-99m Ciprofloxacin. Biodistribution studies in balb/c mice showed significant levels in kidney, liver and intestine. Blood clearance studies showed a slow and biphasic clearance in rabbits. Gamma camera imaging of the rabbits bearing S.aureus infectious lesion confirmed the utility and specificity of the reconstituted kit in imaging infection. The final kit, which was recommended for clinical use was found to be stable for nine months with all its characteristics remaining unchanged from those of the freshly prepared Tc-99m Ciprofloxacin during the entire period of observation. (author)

  20. Clinical significance of 99mTc-DTPA galactosyl human serum albumin scintigram in follow-up after Kasai operation

    The scintigram using 99mTechnetium-DTPA galactosyl human serum albumin (99mTc-GSA) which binds to asialoglycoprotein receptors on hepatocytes is a good index of hepatocyte function in various liver diseases in adult patients. In 43 patients (4 months to 30 years old) who had undergone Kasai procedure, we performed 53 series of 99mTc-GSA scintigrams and checked the laboratory data of blood draw and the clinical status. The indices for blood clearance and liver accumulation were evaluated on the basis of the dynamic data after 99mTc-GSA injection. HH15 as an index of the blood clearance, and LHL15 as an index of the accumulation of the hepatocytes were calculated and the HH15/LHL15 ratio (H/L15) was examined. 99mTc-GSA scintigram correlated with liver function and clinical status. Our results revealed that: The deterioration of the liver functions and clinical status correlates proportionally with H/L15. The results of 99m Technetium-GSA scintigram correlate with several liver function tests, especially direct bilirubin, albumin and choline esterase. This scintigram is an useful index of clinical status and hepatic function as well as the change of the hepatic parenchymal reserve in BA patients, especially for the evaluation of liver transplantation. (author)

  1. Diagnosis and morphological classification of pulmonary arteriovenous fistula by sup(99m)Tc MAA

    Pulmonary A-V fistula was diagnosed and classified morphologically based on the pattern of time-activity curves by sup(99m)Tc MAA. If the diameter of the fistula is large, macro-albumin easily reveals a shunt. If the fistula has the form of an ''aneurysm,'' the degree of shunt is generally slight. (author)

  2. Direct {sup 99m}Tc labeling of Herceptin (trastuzumab) by {sup 99m}Tc(I) tricarbonyl ion

    Chen, W.-J.; Yen, C.-L.; Lo, S.-T.; Chen, K.-T. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lo, J.-M. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan (China)], E-mail: jmlo@mx.nthu.edu.tw

    2008-03-15

    By simply incubating Herceptin (trastuzumab) with [{sup 99m}Tc(CO){sub 3}(OH{sub 2}){sub 3}]{sup +} ion in saline, a significant yield of {sup 99m}Tc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which {sup 99m}Tc(I) tricarbonyl ion can be strongly bound. For practical {sup 99m}Tc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, {alpha}-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [{sup 99m}Tc(CO){sub 3}(OH{sub 2}){sub 3}]{sup +}. Retention of bioactivity of the {sup 99m}Tc(I)-labeled trastuzumab was validated using a cell binding test.

  3. Direct 99mTc labeling of Herceptin (trastuzumab) by 99mTc(I) tricarbonyl ion

    By simply incubating Herceptin (trastuzumab) with [99mTc(CO)3(OH2)3]+ ion in saline, a significant yield of 99mTc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which 99mTc(I) tricarbonyl ion can be strongly bound. For practical 99mTc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, α-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [99mTc(CO)3(OH2)3]+. Retention of bioactivity of the 99mTc(I)-labeled trastuzumab was validated using a cell binding test

  4. 99mTc-labelled biguanide derivatives: chemical speciation modelling thereof and evaluation in vervets

    99mTc-DMSA (dimercaptosuccinic acid) is known to be a safe and effective agent for static renal imaging. However, it has a long uptake time which is a limiting factor in diagnostic procedures and also leads to a relatively high radiation dose being administered to patients. There is a constant search for possible new renal imaging agents with a good resolution, kidney/liver contrast and low radiation dose to all organs. A series of biguanide derivatives (potential as non-insulin-dependent diabetes mellitus agents) labelled with 99mTc were investigated as potential alternative kidney-imaging agents on theoretical grounds (in silico) and their biodistribution (in vivo) verified in a limited number of animal experiments. Such a dual approach has the benefit that it reduces the number of animal experiments needed to evaluate a potential radiopharmaceutical. The blood plasma model shows little or no complexation of the biguanide type ligands by the metal ions in blood plasma. It was therefore expected that these ligands will clear rapidly through the kidneys and liver (increased lipophilicity). These predictions were verified by studies on single vervets comparing them with 99mTc-DMSA as gold standard. All the biguanide derivatives labelled with 99mTc show liver, kidney and gallbladder uptake in vervets. It was shown that the agent 99mTc-CBIG (carboxylbiguanide) has a very fast kidney clearance, which will reduce the dose to organs (as experienced for 99mTc-DMSA), although it's potential as a kidney agent is limited by its gallbladder uptake. (author)

  5. The preclinical pharmacological study of dopamine transporter imaging agent [99mTc]TRODAT-1

    Objective: To investigate the pharmacological characteristics of 99mTc-TRODAT-1 as an imaging agent for dopamine transporter. Methods: (1) The quality control of one-vial formulation produced in China. (2) Biodistribution in rats. (3) Imaging in normal and hemi-Parkinsonian model monkeys. Results: (1) The radiochemical purity of [99mTc]TRODAT-1 was about 79.9% evaluated by TLC. It was stable for 2.5 hours at room temperature. (2) The clearance of [99mTc]TRODAT-1 in the blood of rats was fast. The major portion of radioactivity was excreted by hepatobiliary system. (3) The brain uptake was moderate. But the agent had high-affinity binding to DAT which was highly concentrated in striatal area and there was no specific uptake in cerebellum. The ratio of ST/CB was high. (4) Pretreatment with haloperidol, a non-competing ligand, did not result in any significant change in the level of striatal uptake. (5) The distribution pattern as well as the brain regional uptake of [99mTc]TRODAT-1 did not display any significant difference between male and female rats at 60 min post-injection. (6) Monkeys' SPECT images clearly displayed the normal uptake and the pathologic changes in striatal area at 3 hours post-injection. The semi-quantitative analysis, ST/CB ratio, could reveal the specific uptake value for [99mTc]TRODAT-1 in reflecting the numeral and functional changes in DAT. Conclusion: [99mTc]TRODAT-1 labeled by one-vial formulation of China can be the imaging agent of DAT in clinical study. It proves to be effective and promising radiopharmaceuticals in vivo assessment of the loss of dopamine neurons in Parkinson's disease and other neurodegenerative disease

  6. Investigation into the effect of fenoterol on mucociliary clearance in patients with chronic bronchitis

    We investigated the effects of fenoterol, a selective β2 adrenoceptor stimulant, on mucociliary clearance in 12 patients with chronic bronchitis. Mucociliary clearance was measured with a scintillation camera after inhalation of a 99mTc labeled aerosol. Fenoterol was administered one h after acquisition commenced and imaging was maintained for a further two h. Three regions of interest (ROI) were selected over each lung to generate time activity curves. Corrections for decay, alveolar deposition (using 24 h image), cough and movement of activity through each ROI were carried out. An exponential function was fitted to the clearance curves to determine clearance rates. The increase in percentage clearance after fenoterol administration for the left and right whole lung ROI was 35% and 36% per h respectively (P = 0.006 and 0.020). Fenoterol enhances cilial clearance in chronic bronchitis patients. (orig.)

  7. Study on the preparation of methylene diphosphonate (MDP) labeling with 99mTc for bone scintigraphy

    The 99mTc-MDP kit was prepared by using aseptic technique. The composition of MDP invivo kit including 5 mg MDP, 0.5 mg stannous chloride, 0.5 mg ascorbic acid and 5 mg sodium chloride. The kit produces 99mTc-MDP with more than 95% labelling efficiency at pH 6-7 when mixed with requisite amount of 99mTc-pertechnetate. The preparation has been found sterity, pyrogen free, to be sufficiency stable invitro as well as invivo, blood clearance. After intravenous administrations abound 50% of the dose is accumulated and retained by the skeleton. The kit provides quality product in high yield, more stable than other phosphonate kit, high bone uptake. High avidity of 99mTc-MDP for bone imaging makes it a promising agent for the detection of bone diseases. (author)

  8. Comparative scintigraphic study of renal function with 99mTc-Mercaptoacetyl-triglycine and 99mTc-Ethylenedicysteine

    Beiki D.; Eftekhari M; Fallahi B.; Gheisari F.; Hozhabrosadati M.; Fard-Esfahani A.; Takavar A; Gholamrezanezhad A.; Saghari M. Ansari Gilani K.

    2008-01-01

    99mTc-MAG3 is a standard radiotracer for renal dynamic functional study. Despite its"nproperties for clinical uses, it has numerous technical limitations. 99mTc-EC is also a tubular"nradiotracer for renal imaging, which has not been used worldwide. In this study, the use of 99mTc-EC"nand 99mTc-MAG3 for renal functional study were compared."nMethods: Thirty five patients (20 male, 15 female; mean age of 34.63 ±10.69 years) were entered in"nthe study. About 1...

  9. (99m)Tc-labeled porphyrin-lipid nanovesicles.

    Lee, Jae-Ho; Shao, Shuai; Cheng, Kenneth T; Lovell, Jonathan F; Paik, Chang H

    2015-01-01

    Porphyrin-lipid nanovesicles (PLN) have been developed with intrinsic capabilities as activatable multimodal photonic contrast agents. Radiolabeling of PLN encapsulating drugs could eventually be able to provide quantitative in vivo information for diagnosing and treating diseases. In this study, we developed (99m)Tc-labeled porphyrin-lipid nanovesicles ((99m)Tc-PLN) as a cargo-encapsulated formulation without significant impact on liposome integrity and encapsulation stability. 50 mM calcein was encapsulated into PLN by probe sonication. The size of the PLN was about 150 nm. The PLN were then reacted with (99m)Tc using SnCl2 dissolved in 1 mM HCl as a reducing agent and incubated for 10 min at 22 °C. The radiolabeling efficiency and stability of (99m)Tc-PLN were evaluated by instant thin-layer chromatography and low-pressure liquid chromatography (LPLC). (99m)Tc labeling was successful with a >92% labeling efficiency. LPLC showed that the liposomal elution peaks of the porphyrin-lipid and the calcein overlapped with the radioactivity elution peak of (99m)Tc-labeled PLN. The (99m)Tc-labeling procedure did not change the size of PLN. Encapsulated calcein remained inert inside PLN. Thus, this work lays out a simple and effective radiolabeling method using SnCl2 in HCl in the preparation of (99m)Tc-PLN. PMID:24963601

  10. Labelling of gentamicin sulphate with99mTc

    The labelling of gentamicin sulphate with99mTc and its optimization is shown. The Quality control of gentamicin sulphate -99mTc, and a study about PH and mass variation of SnCl2 are described. (M.J.C)