Abstract
The aim of this retrospective study was to determine the heart-to-mediastinum ratio (HMR) of 123I-metaiodobenzylguanidine (MIBG) uptake obtained using a multi-pinhole cadmium-zinc-telluride (CZT)-based camera (Discovery NM 530c, DNM-530c, GE Healthcare, Milwaukee, WI, USA) in comparison with that obtained using conventional planar imaging (Infinia, GE Healthcare, Milwaukee, WI, USA). Methods: Forty consecutive heart failure patients underwent planar acquisition 4 h after 123I-MIBG injection (191±41 MBq). To localize the heart using DNM-530c, 99mTc-tetrofosmin (358±177 MBq) was administered and a dual-isotope acquisition was performed. The HMRs were calculated (i) with conventional planar imaging (HMRplanar), (ii) with anterior reprojection images (HMRreproj) and (iii) with transaxial reconstructed images using DNM-530c (HMRtransaxial). In a phantom study, we estimated a linear model fitting the CZT to the planar data that was further applied to provide corrected CZT HMR values in patients (cHMRreproj and cHMRtransaxial respectively). Results: Thirty-four men and 6 women (71±9 y/o) with ischemic (22 patients) and nonischemic (18 patients) heart failure completed the study. Twenty-two of the 40 patients (55%) were New York Heart Association class II, and ejection fraction was 35±9 %. Compared to HMRplanar (1.44±0.14), HMRreproj (1.12±0.19) and HMRtransaxial (1.35±0.34) were decreased (p<0.0001 and p<0.01 respectively). Corrected cHMRreproj (1.54±0.09) and cHMRtransaxial (1.45±0.14) were different (p<0.0001). Lin’s concordance correlation and Bland-Altman analysis demonstrated an almost perfect concordance and a high agreement between HMRplanar and cHMRtransaxial (P = NS) using transaxial reconstructed images but not with cHMRreproj using reprojection images (p<0.0001). Conclusion: This study demonstrated that determination of late HMR of cardiac 123I-MIBG uptake using dual-isotope (123I and 99mTc) acquisition on a multi-pinhole CZT camera (DNM-530c) is feasible in patients with heart failure. However, this determination should be performed using transaxial reconstructed images and a linear correction based on phantom data acquisitions.
- Cardiology (basic/technical)
- Cardiology (clinical)
- SPECT
- CZT
- DNM 530c
- Heart-to-mediastinum ratio
- MIBG
- dual-isotope
- Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.