ABSTRACT
The total plasma disappearance of the non-ionic contrast medium iohexol was determined by X-ray fluorescence technique following intravenous urography in 10 children aged between 2 and 13 years. For comparison the plasma disappearance of 99Tcm-DTPA was estimated both 2 days before and simultaneously with the iohexol study. High correlations between the three sets of data were found and no change in the glomerular filtration rate was detected following injection of contrast medium. It was also found that reliable estimates of the glomerular filtration rate can be obtained from two plasma samples of 1 ml each, taken 3 h and 4 h after the injection of the contrast medium.
Subject(s)
Glomerular Filtration Rate , Iohexol/pharmacokinetics , Organotechnetium Compounds/pharmacokinetics , Pentetic Acid/pharmacokinetics , Urography , Adolescent , Child , Child, Preschool , Female , Fluorescence , Humans , Male , Radionuclide Imaging , Technetium Tc 99m Pentetate , Urologic Diseases/diagnostic imagingABSTRACT
Blood samples were taken from 21 subjects at 2 to 4 hours after simultaneous injection of contrast medium (metrizoate) for urography and 51Cr-EDTA. Clearance calculations were performed using the single injection (single slope) technique. The plasma concentrations of 51Cr-EDTA and contrast medium were measured by gamma counting and X-ray fluorescence analysis, respectively. A good correlation was found between the clearance of 51Cr-EDTA and clearance of contrast medium (r = 0.94).
Subject(s)
Chromium Radioisotopes , Edetic Acid , Glomerular Filtration Rate , Iodobenzoates , Metrizoic Acid , Spectrometry, X-Ray Emission , Urography , Adult , Aged , Aged, 80 and over , Chromium Radioisotopes/pharmacokinetics , Edetic Acid/pharmacokinetics , Female , Humans , Male , Metabolic Clearance Rate , Metrizoic Acid/analogs & derivatives , Metrizoic Acid/pharmacokinetics , Middle AgedABSTRACT
A noninvasive method for the estimation of kidney function is described. The use of radioactive tracers and the sampling of plasma and urine are omitted. The method has been used in patients referred for urography and who had therefore been injected with routine amounts of iodine-containing urographic contrast medium. After urography, the elimination rates of urographic contrast medium from both serum and finger tissue were determined and compared during a 2-hour period that began two hours after injection of contrast medium. The elimination of iodine in finger tissue was measured noninvasively using x-ray fluorescence analysis. A strong degree of correlation was found between the elimination rates from serum and finger tissue and between the total clearances calculated from the serum and finger measurements. Thus, after urography estimation of kidney function may be obtained as a fringe benefit by x-ray fluorescence measurements of the elimination rate of an iodine-containing contrast medium from tissue or from serum.
Subject(s)
Contrast Media/metabolism , Kidney/metabolism , Adolescent , Adult , Aged , Female , Fingers/metabolism , Glomerular Filtration Rate , Humans , Iodine/blood , Kidney/diagnostic imaging , Male , Metrizoic Acid/metabolism , Middle Aged , Spectrometry, X-Ray Emission , Tissue Distribution , UrographyABSTRACT
A noninvasive method for glomerular filtration rate-determination, in which the use of radioactive tracers and sampling of plasma and urine can be omitted, is described. After injection of iodinated contrast material in rabbits, the iodine content of tissue, serum, and urine is measured by means of x-ray fluorescence analysis. The disappearance rates of iodine in tissue and serum are found to be the same, and a strong correlation is found between clearance values calculated from serum and tissue measurements. This indicates the possibility of evaluating kidney function by x-ray fluorescence analysis of contrast material in tissue only.
