The Bnai Zion Planar Method: a simplified technique for the quantitation of the absolute renal uptake of (99m)Tc-DMSA in children.
OBJECTIVE
Radionuclide imaging of the kidneys using dimercaptosuccinic acid chelate labeled with technetium-99m (Tc-DMSA) is a well-established method for evaluating the extent of kidney parenchymal involvement in the scenario of urinary tract infection and for the estimation of the functional renal mass. We have developed a simplified technique, Bnai Zion Planar Method (BZPM), to estimate absolute DMSA uptake by the kidneys, which uses a shorter time of acquisition and does not require cumbersome calculations of attenuation correction. The aim of this study was to validate this technique by comparing it with the Quantitative DMSA single-photon emission computed tomography (SPECT) (QDMSA) measurements as the reference method.


METHODS
Sixty-one consecutive children (mean age 5.4+/-4.8 years) were included in the study. Absolute uptake of the radiopharmaceutical by the kidneys was measured using the QDMSA SPECT methods described earlier with data acquisition of 20 min. Kidney volumes and radioactivity concentration measurements were calculated on the reconstruction data using the threshold method. For the simplified technique (BZPM), a planar posterior view of the kidneys was acquired for 1 min at the end of the QDMSA SPECT study.


RESULTS
In both kidneys we observed a significant strong correlation between the two methods. BZPM measurements were very similar to those obtained using the validated QDMSA method, as determined by linear regression analysis (Pearson's r=0.924, P<0.001), r(2)=0.854. The uptake according to QDMSA can be predicted by the uptake measured by the BZPM method using the following regression equation: QDMSA=0.445+1.061 BZPM.


CONCLUSIONS
BZPM estimation in children using the newly proposed planar method was found to be nearly identical to the validated QDMSA SPECT method.
Gorenberg
Miguel
M
Department of Nuclear Medicine, Bnai Zion Medical Center, Rappaport Faculty of Medicine, Technion, Haifa, Israel. miguel.gorenberg@b-zion.org.il
Radan
Lea
L
Kosakov
Ronen
R
Amirav
Israel
I
D000293:Adolescent; D001692:Biological Transport; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D012044:Regression Analysis; D015203:Reproducibility of Results; D019783:Technetium Tc 99m Dimercaptosuccinic Acid / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
D019783:Technetium Tc 99m Dimercaptosuccinic Acid