Evaluation of interobserver variability of parenchymal phase of Tc-99m mercaptoacetyltriglycine and Tc-99m dimercaptosuccinic acid renal scintigraphy.
OBJECTIVE
The aim of this study was to investigate the variability in the interpretation of parenchymal abnormalities and to assess the differences in interpretation of routine renal scintigraphic findings on posterior view of technetium-99m dimercaptosuccinic acid (pvDMSA) scans and parenchymal phase of technetium-99m mercaptoacetyltriglycine (ppMAG3) scans by using standard criterions to make standardization and semiquantitative evaluation and to have more accurately correlation.


METHODS
Two experienced nuclear medicine physicians independently interpreted pvDMSA scans of 204 and ppMAG3 scans of 102 pediatric patients, retrospectively. Comparisons were made by visual inspection of pvDMSA scans, and ppMAG3 scans by using a grading system modified from Itoh et al. According to this, anatomical damage of the renal parenchyma was classified into six types: Grade 0-V. In the calculation of the agreement rates, Kendall correlation (tau-b) analysis was used.


RESULTS
According to our findings, excellent agreement was found for DMSA grade readings (DMSA-GR) (tau-b = 0.827) and good agreement for MAG3 grade readings (MAG3-GR) (tau-b = 0.790) between two observers. Most of clear parenchymal lesions detected on pvDMSA scans and ppMAG3 scans identified by observers equally. Studies with negative or minimal lesions reduced correlation degrees for both DMSA-GR and MAG3-GR.


CONCLUSIONS
Our grading system can be used for standardization of the reports. We conclude that standardization of criteria and terminology in the interpretations may result in higher interobserver consistency, also improve low interobserver reproducibility and objectivity of renal scintigraphy reports.
Department of Nuclear Medicine, Kayseri Training and Research Hospital, Kayseri, Turkey.
Zeynep
Z
Erdoğan
Nuclear Medicine, Erciyes University School of Medicine, Kayseri, Turkey.
Ummühan
U
Abdülrezzak
Department of Nuclear Medicine, Kayseri Training and Research Hospital, Kayseri, Turkey.
Güler
G
Silov
Department of Nuclear Medicine, Kayseri Training and Research Hospital, Kayseri, Turkey.
Ayşegül
A
Ozdal
Department of Nuclear Medicine, Kayseri Training and Research Hospital, Kayseri, Turkey.
Ozgül
O
Turhal
DMSA; MAG3; observer variability; renal scintigraphy