Toward Standardization of Imaging Time Points for ¹²³I-MIBG Scan

Abstract

In this issue of the journal, Dimitriu-Leen et al. addressed a question of whether an early late imaging (e.g., 1, 2, or 3 hours after tracer injection) can be used as an alternative to 4 hour ¹²³I-MIBG imaging in terms of heart-to-mediastinum uptake ratio (HMR) and washout rate (WR). They found that, by applying the linear regression model, HMR and WR obtained at 3 hours after injection can accurately estimate those at 4 hours. Additionally, the parameters estimated at 2 hours showed a close correlation to those at 4 hours. This study shows that a shorter imaging protocol is feasible without loss of clinical significance as compared to 4 hour imaging, which is certainly more convenient for the patients. More importantly, collected ¹²³I-MIBG imaging data from different acquisition protocols can directly be compared and exchangeable. Because we now have tools for standardization of data derived from different camera systems, the results of this study would further facilitate the use of ¹²³I-MIBG imaging as a reliable aid for risk stratification of HF patients.