Clinical value of early-phase 99mTc-MIBI SPECT in rapid washout parathyroid adenomas.

OBJECTIVE: Tc-MIBI) imaging, potentially leading to false-negative localization. This retrospective single-center study evaluated the clinical value of early-phase single photon emission computed tomography (SPECT) compared with delayed-phase SPECT in detecting rapid washout parathyroid adenomas, particularly in centers without access to SPECT/computed tomography (CT), and assessed whether this washout pattern could be predicted by biochemical parameters. SUBJECTS AND METHODS: Tc-MIBI SPECT imaging were included. Early-phase and delayed-phase SPECT images were independently reviewed by two experienced nuclear medicine physicians. Lesion detection rates were compared using McNemar's test, interobserver agreement was assessed using Cohen's kappa coefficient, and preoperative biochemical parameters were compared between adenomas detected only on early-phase imaging and those visible on delayed-phase imaging. RESULTS: Early-phase SPECT enabled detection of all surgically confirmed adenomas, whereas delayed-phase SPECT failed to identify 8 of 18 lesions (44%) due to rapid tracer washout, with a statistically significant difference between the two phases (P