Diagnostic accuracy of SPECT/CT in parathyroid adenoma detection: impact of radiopharmaceutical choice and quality control practices

To evaluate the diagnostic accuracy of SPECT/CT for localizing parathyroid adenomas and to determine how radiopharmaceutical choice (MIBI vs. Myoview) and quality control (QC) practices affect detection performance and administered dose consistency in clinical practice. This retrospective study included 136 patients who underwent dual-phase parathyroid scintigraphy with SPECT/CT at Al-Hada Armed Forces Hospital. Patients were classified into four groups according to radiopharmaceutical (MIBI or Myoview) and QC status (Regular or Irregular QC). Administered activity, detection accuracy, lesion localization, and concordance with surgical findings were assessed. Diagnostic performance was compared between SPECT/CT and planar imaging. Statistical analyses included ANOVA, χ² tests, and correlation analysis. SPECT/CT demonstrated significantly higher diagnostic accuracy than planar imaging across all groups. Regular QC conditions produced the most consistent administered activities and the highest detection rate (97.1%), whereas Irregular QC significantly reduced accuracy to 72.1%. MIBI showed superior performance under QC variability, maintaining higher sensitivity and more consistent lesion localization than Myoview. SPECT/CT also improved detection of ectopic and multi-gland disease compared with planar imaging. SPECT/CT provides high diagnostic accuracy for parathyroid adenoma detection, but performance is strongly influenced by QC practices and, to a lesser extent, by radiopharmaceutical choice. Regular QC ensures optimal dose consistency and diagnostic reliability, while MIBI offers greater robustness under variable QC conditions. These findings support QC standardization and radiopharmaceutical selection as key determinants of improved clinical outcomes.