SPECT of Serotonin Transporters Using 123I-ADAM: Optimal Imaging Time After Bolus Injection and Long-Term Test–Retest in Healthy Volunteers

Journal of Nuclear Medicine

Enric Álvarez¹  Jordi Llop¹  Juan C. Pascual¹  Iluminada Corripio¹  Javier Perich¹  María M. Penengo¹  Mónica Danús¹  Dolors Puigdemont¹  Santiago Bullich¹  Ana M. Catafau¹  Víctor Pérez¹ 

关键词: ¹²³I-ADAM;    SPECT;    test–retest;    serotonin transporter;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

123I-ADAM (2-([2-([dimethylamino]methyl)phenyl]thio)-5-123I-iodophenylamine) has been recently proposed as a new serotonin transporter (SERT) ligand for SPECT. The objective of this study was to characterize 123I-ADAM in healthy volunteers. 123I-ADAM distribution in the normal brain, pseudoequilibrium interval after a single injection, normal specific uptake values, and long-term test–retest variability and reliability were investigated. Methods: Ten healthy volunteers underwent 2 SPECT sessions under the same conditions 47.6 ± 24.0 d apart. Scans were sequentially acquired from the time of 123I-ADAM intravenous injection up to 12 h after injection. Regions of interest (ROIs) for cerebellum (C), midbrain, thalamus, striatum, mesial temporal region, and cortex were drawn on MR images and pasted to corresponding SPECT slices after coregistration. Specific uptake ratios (SURs) at pseudoequilibrium and the simplified reference tissue model (SRTM) methods were used for quantification. SURs were obtained as ([region − C]/C) at each time point. Test–retest variability and reliability (intraclass correlation coefficient [ICC]) were calculated. Results: The highest 123I-ADAM specific uptake was found in the midbrain and thalamus, followed by the striatum and mesial temporal region. Quantification results using SUR and SRTM were correlated with R = 0.93 (test) and R = 0.94 (retest). SURs remained stable in all regions from 4 to 6 h after injection. Using SUR, test–retest variability/ICC were 13% ± 11%/0.74 in midbrain, 16% ± 13%/0.63 in thalamus, 19% ± 18%/0.62 in striatum, and 22% ± 19%/0.05 in mesial temporal region. Conclusion: 123I-ADAM accumulates in cerebral regions with high known SERT density. The optimal imaging time for 123I-ADAM SPECT quantification is suggested to be from 4 to 6 h after a single injection. Long-term test–retest variability and reliability found in the midbrain are comparable to that reported with other 123I-labeled SPECT ligands. These results support the use of 123I-ADAM SPECT for SERT imaging after a single injection in humans.

【 授权许可】

Unknown