scholarly journals Effect of Doping Agent on Elution Profile of Tc-99m Generationand Labeling of Tc-99m With

2014 ◽  
Vol 27 (2) ◽  
pp. 41-45 ◽  
Author(s):  
M Ruhul Amin ◽  
Azizul Haque ◽  
Hreeshit Kumar ◽  
Sayem Yousuf
Keyword(s):  
Chemical Engineering ◽  
Radioactive Decay ◽  
Elution Profile ◽  
Nacl Solution ◽  
Doping Agent ◽  
Time Activity ◽  
As Doping ◽  
Mobile Phases ◽  
Activity Curve ◽  
Effect Of Doping

Effect of doping agent on elution profile of Tc-99m generation and labeling of Tc-99m with MDP (Methylene diphosphonate) were carried out and studied. Tc -99m is one of the most talked element of modern radio pharmacy for its multiple application in diagnosis.Tc-99m is produced from Mo-99 through radioactive decay process. In our work two column chromatographic generator were made with Alumina column and loaded with Mo-99 which would be converted into Tc-99m eventually. Elution was taken by passing saline( 1 mL 0.9% NaCl solution and 1 mL 0.9% NaCl solution with 0.0045% NaNO3 as doping agent) each time and the activities of Tc -99m was measured by a Dose Calibrator. Elutions of Tc-99m were carried out several times and each time activity was measured. It is observed that almost 60 -75 % activity can be found in 2nd elution. Studying elution profile it is seen that activity curve reaches at pick in 2nd elution and afterwards gradually slopes down. Each time better activity is achieved by using pure saline. In spite of lower activity, this research resulting highly recommendation of using NaNO3 as a doping agent in NaCl saline in case of using elution because of its higher purity and RCP value . Tc -99m is applied over a biological body as a labeled compound . In this case MDP was used as a labeling compound . With a view of carrying out the RCP value of labeled compound, paper chromatography technique is done with various mobile phases in Whatman No 1 paper. Purity (%) is ranging from 30 – 90 % and NaNO3 doped NaCl radioactive solution shows better purity performance than pure NaCl solution in every different mobile phase . DOI: http://dx.doi.org/10.3329/jce.v27i2.17800 Journal of Chemical Engineering, IEB Vol. ChE. 27, No. 2, December 2012: 41-45

The Influence of Lactate and Dipyridamole on Myocardial Fatty Acid Metabolism in Man, Traced with 123l-17-lodo-heptadecanoic Acid

1990 ◽  
Vol 29 (01) ◽  
pp. 28-34 ◽  
Author(s):  
F. C. Visser ◽  
M. J. van Eenige ◽  
G. Westera ◽  
J. P. Roos ◽  
C. M. B. Duwel
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Metabolism ◽  
Acid Metabolism ◽  
Time Activity ◽  
Time Value ◽  
Myocardial Fatty Acid Metabolism ◽  
Coronary Vasodilatation ◽  
Activity Curve ◽  
Normal Human ◽  
Plasma Lactate Level

Changes in myocardial metabolism can be detected externally by registration of time-activity curves after administration of radioiodinated fatty acids. In this scintigraphic study the influence of lactate on fatty acid metabolism was investigated in the normal human myocardium, traced with 123l-17-iodoheptadecanoic acid (123l-17-HDA). In patients (paired, n = 7) lactate loading decreased the uptake of 123l-17-HDA significantly from 27 (control: 22-36) to 20 counts/min/pixel (16-31; p <0.05 Wilcoxon). The half-time value increased to more than 60 rriin (n = 5), oxidation decreased from 61 to 42%. Coronary vasodilatation, a well-known side effect of lactate loading, was studied separately in a dipyridamole study (paired, n = 6). Coronary vasodilatation did not influence the parameters of the time-activity curve. These results suggest that changes in plasma lactate level as occurring, among other effects, during exercise will influence the parameters of dynamic 123l-17-HDA scintigraphy of the heart.

Measurement of Renal Parenchymal Transit Time of 99mTc-MAG3 Using Factor Analysis

1990 ◽  
Vol 29 (04) ◽  
pp. 170-176 ◽  
Author(s):  
M. V. Yester ◽  
Eva Dubovsky ◽  
C. D. Russell
Keyword(s):  
Factor Analysis ◽  
Transit Time ◽  
Region Of Interest ◽  
Initial Slope ◽  
Cortical Region ◽  
Time Activity ◽  
Appearance Time ◽  
Activity Curve ◽  
System Factor ◽  
Collecting System

Renal parenchymal transit time of the recently introduced radiopharmaceutical 99mTc-MAG3 (mercaptoacetylglycylglylcylglycinel) was measured in 37 kidneys, using factor analysis to separate parenchymal activity from that in the collecting system. A new factor algorithm was employed, based on prior interpolative background subtraction and use of the fact that the initial slope of the collecting system factor time-activity curve must be zero. The only operator intervention required was selection of a rectangular region enclosing the kidney (by identifying two points at opposite corners). Transit time was calculated from the factor time-activity curves both by deconvolution of the parenchymal factor curve and also by measuring the appearance time for collecting system activity from the collecting system factor curve. There was substantial agreement between the two methods. Factor analysis led to a narrower range of normal values than a conventional cortical region-of-interest method, presumably by decreasing crosstalk from the collecting system. In preliminary trials, the parenchymal transit time did not well separate four obstructed from seventeen unobstructed kidneys, but it successfully (p <0.05) separated six transplanted kidneys with acute rejection or acute tubular necrosis from 10 normal transplants.

Analysis of Myocardial Time-Activity Curves of 123l-Heptadecanoic Acid II. The Acquisition Time

1987 ◽  
Vol 26 (06) ◽  
pp. 248-252 ◽  
Author(s):  
M. J. van Eenige ◽  
F. C. Visser ◽  
A. J. P. Karreman ◽  
C. M. B. Duwel ◽  
G. Westera ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Acquisition Time ◽  
Half Time ◽  
Constant Ratio ◽  
Time Activity ◽  
Time Activity Curve ◽  
Time Value ◽  
Activity Curve ◽  
Low Amplitude ◽  
Parameter Values

Optimal fitting of a myocardial time-activity curve is accomplished with a monoexponential plus a constant, resulting in three parameters: amplitude and half-time of the monoexponential and the constant. The aim of this study was to estimate the precision of the calculated parameters. The variability of the parameter values as a function of the acquisition time was studied in 11 patients with cardiac complaints. Of the three parameters the half-time value varied most strongly with the acquisition time. An acquisition time of 80 min was needed to keep the standard deviation of the half-time value within ±10%. To estimate the standard deviation of the half-time value as a function of the parameter values, of the noise content of the time-activity curve and of the acquisition time, a model experiment was used. In most cases the SD decreased by 50% if the acquisition time was increased from 60 to 90 min. A low amplitude/constant ratio and a high half-time value result in a high SD of the half-time value. Tables are presented to estimate the SD in a particular case.

scholarly journals Voxelwise Principal Component Analysis of Dynamic [S-Methyl-11C]Methionine PET Data in Glioma Patients

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2342
Author(s):  
Corentin Martens ◽  
Olivier Debeir ◽  
Christine Decaestecker ◽  
Thierry Metens ◽  
Laetitia Lebrun ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Added Value ◽  
Time Activity ◽  
Positron Emission ◽  
Activity Curve ◽  
The Mean ◽  
Mean Time ◽  
Met Pet

Recent works have demonstrated the added value of dynamic amino acid positron emission tomography (PET) for glioma grading and genotyping, biopsy targeting, and recurrence diagnosis. However, most of these studies are based on hand-crafted qualitative or semi-quantitative features extracted from the mean time activity curve within predefined volumes. Voxelwise dynamic PET data analysis could instead provide a better insight into intra-tumor heterogeneity of gliomas. In this work, we investigate the ability of principal component analysis (PCA) to extract relevant quantitative features from a large number of motion-corrected [S-methyl-11C]methionine ([11C]MET) PET frames. We first demonstrate the robustness of our methodology to noise by means of numerical simulations. We then build a PCA model from dynamic [11C]MET acquisitions of 20 glioma patients. In a distinct cohort of 13 glioma patients, we compare the parametric maps derived from our PCA model to these provided by the classical one-compartment pharmacokinetic model (1TCM). We show that our PCA model outperforms the 1TCM to distinguish characteristic dynamic uptake behaviors within the tumor while being less computationally expensive and not requiring arterial sampling. Such methodology could be valuable to assess the tumor aggressiveness locally with applications for treatment planning and response evaluation. This work further supports the added value of dynamic over static [11C]MET PET in gliomas.

Impulse-response function of splanchnic circulation with model-independent constraints: theory and experimental validation

2003 ◽  
Vol 285 (4) ◽  
pp. G671-G680 ◽  
Author(s):  
Ole L. Munk ◽  
Susanne Keiding ◽  
Ludvik Bass
Keyword(s):  
Portal Vein ◽  
Impulse Response ◽  
Response Function ◽  
Mean Transit Time ◽  
Impulse Response Function ◽  
Parameter Estimates ◽  
Time Activity ◽  
Time Activity Curve ◽  
Transit Times ◽  
Activity Curve

Modeling physiological processes using tracer kinetic methods requires knowledge of the time course of the tracer concentration in blood supplying the organ. For liver studies, however, inaccessibility of the portal vein makes direct measurement of the hepatic dual-input function impossible in humans. We want to develop a method to predict the portal venous time-activity curve from measurements of an arterial time-activity curve. An impulse-response function based on a continuous distribution of washout constants is developed and validated for the gut. Experiments with simultaneous blood sampling in aorta and portal vein were made in 13 anesthetized pigs following inhalation of intravascular [15O]CO or injections of diffusible 3- O-[11C]methylglucose (MG). The parameters of the impulse-response function have a physiological interpretation in terms of the distribution of washout constants and are mathematically equivalent to the mean transit time ( T̄) and standard deviation of transit times. The results include estimates of mean transit times from the aorta to the portal vein in pigs: T̄ = 0.35 ± 0.05 min for CO and 1.7 ± 0.1 min for MG. The prediction of the portal venous time-activity curve benefits from constraining the regression fits by parameters estimated independently. This is strong evidence for the physiological relevance of the impulse-response function, which includes asymptotically, and thereby justifies kinetically, a useful and simple power law. Similarity between our parameter estimates in pigs and parameter estimates in normal humans suggests that the proposed model can be adapted for use in humans.

Measurement of arterial time-activity curve by monitoring continuously drawn arterial blood with an external detector: Errors and corrections

1988 ◽  
Vol 2 (1) ◽  
pp. 7-12 ◽  
Author(s):  
Michio Senda ◽  
Sadahiko Nishizawa ◽  
Yoshiharu Yonekura ◽  
Takao Mukai ◽  
Hideo Saji ◽  
...  
Keyword(s):  
Time Activity ◽  
Time Activity Curve ◽  
Arterial Blood ◽  
Activity Curve

Total cerebral blood volume calculated from a model of [99mTc]pertechnetate distribution in the head

1993 ◽  
Vol 74 (6) ◽  
pp. 2886-2895 ◽  
Author(s):  
A. Keyeux ◽  
D. Ochrymowicz-Bemelmans ◽  
C. Van Eyll ◽  
A. A. Charlier
Keyword(s):  
Blood Volume ◽  
Cerebral Blood Volume ◽  
Bolus Injection ◽  
Compartment Model ◽  
Normal Density ◽  
Jugular Veins ◽  
Time Activity ◽  
99Mtc Pertechnetate ◽  
Activity Curve ◽  
Carotid And Vertebral Arteries

A method for calculation of the blood volume from the internal carotid and vertebral arteries to the internal jugular veins [total cerebral blood volume (TCBV)] was validated. This was achieved noninvasively in anesthetized rats from the time-activity curve recorded over the head after [99mTc]pertechnetate (Tc) intravenous bolus injection. Tc had the advantage over many other tracers in that it rapidly and evenly distributed in blood cells and plasma. Tc was found to behave in the head according to a two-parallel-compartment model containing a fast cerebral compartment and a slow extracerebral compartment. This model was mathematically described by a sum of two lagged normal density curves (LNDC) that fitted the head curve adequately. Responses of the LNDC parameters to flow and volume variations were first tested on a hydraulic setup. TCBV was calculated from the LNDC parameters of the cerebral fast compartment and the simultaneously determined cardiac output. In normocapnic rats, TCBV amounted to 49 +/- 7 (SD) microliters/g, distributed approximately two-thirds in the extra-parenchymal and one-third in the intraparenchymal cerebral vasculatures.

A simple on-line arterial time-activity curve detector for [O-15] water PET studies

1997 ◽  
Vol 44 (4) ◽  
pp. 1613-1617 ◽  
Author(s):  
S.D. Wollenweber ◽  
R.D. Hichwa ◽  
L.L.B. Ponto
Keyword(s):  
Time Activity ◽  
Time Activity Curve ◽  
Activity Curve ◽  
On Line ◽  
O 15
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