title: Relative and absolute 99Tcm-DMSA uptake measurements in normal and obstructed kidneys.
abstract: Relative and absolute 99Tcm-DMSA uptake measurements were carried out on 25 adult patients among whom there were 23 normal and 25 malfunctioning kidneys. Data were collected at 3 and 6 h post intravenous tracer injection. Four methods of calculating absolute uptake were investigated and evaluated. These were based on: (1) posterior view and measured kidney depth; (2) posterior view and Raynauld's depth; (3) geometric mean assuming kidney thickness is small enough not to introduce self attenuation of counts in the kidney itself; (4) geometric mean taking kidney thickness into account. Whilst (1) and (2) were found to overestimate and underestimate renal uptake by up to 5 and 14%, respectively, (3) and (4) were found to be more accurate and comparable. The measurement of relative DMSA uptake (right to left) showed no change between the 1 and 6 h measurements for both obstructed and non-obstructed kidneys. Based on the results from method 4, the absolute renal DMSA uptake had a mean value of 25.4%, S.D. 8.9% and 30.0%, S.D. 9.2% at 3 and 6 h, respectively, for normal/non obstructed kidneys. For obstructed kidneys (responding to frusemide), the mean uptake was 23.0%, S.D. 7.2 and 25.6%, S.D. 6.7% at 3 and 6 h, respectively. For obstructed kidneys not responding to frusemide, the mean uptake was 16.8%, S.D. 3.9 and 20.6%, S.D. 4.8% at 3 and 6 h, respectively. No correlation was found between absolute DMSA uptake and degree of renal obstruction.
authors.affiliation: Institute of Nuclear Medicine, University College, London, UK.
authors.forename: M C
authors.initials: MC
authors.lastname: Zananiri
authors.forename: P H
authors.initials: PH
authors.lastname: Jarritt
authors.forename: M
authors.initials: M
authors.lastname: Sarfarazi
authors.forename: P J
authors.initials: PJ
authors.lastname: Ell
mesh_terms: D000328:Adult; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000378:metabolism*; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000378:metabolism*; D008433:Mathematics; D008722:Methods; D009942:Organometallic Compounds / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D004113:Succimer / Q000493:pharmacokinetics*; D013438:Sulfhydryl Compounds / Q000493:pharmacokinetics*; D013667:Technetium; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
chemical_list: D009942:Organometallic Compounds; D013438:Sulfhydryl Compounds; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D013667:Technetium; D004113:Succimer