PT  - JOURNAL ARTICLE
AU  - Rahman, Mahmudur
AU  - Islam, Muhammad
AU  - Tsujikawa, Tetsuya
AU  - Kiyono, Yasushi
AU  - Okazawa, Hidehiko
TI  - A new method for [<sup>123</sup>I]FP-CIT specific binding ratio estimation in evaluation of striatal function
DP  - 2018 May 01
TA  - Journal of Nuclear Medicine
PG  - 1652--1652
VI  - 59
IP  - supplement 1
4099  - http://jnm.snmjournals.org/content/59/supplement_1/1652.short
4100  - http://jnm.snmjournals.org/content/59/supplement_1/1652.full
SO  - J Nucl Med2018 May 01; 59
AB  - 1652Objectives: Dopamine transporter (DAT) imaging using [123I]ioflupane (FP-CIT) SPECT is widely used for clinical assessment of the nigrostriatal function in patients with parkinsonian syndromes (PS). To evaluate presynaptic functional reduction of the striata, the specific binding ratio (SBR), semi-quantitative values of FP-CIT accumulation, is usually obtained using various methods. In this study, a new method for extraction of striatal volume of interest (VOI) was developed to calculate the SBR appropriately. The results of SBR from our method were compared with those from the previous method by Tosicci-Bolt et al. Methods: A total of 200 patients (mean age 72 ± 10 y) who were suspected of PS or dementia with Lewy body (DLB) were included in this study. The patients were divided into 3 groups of PS (n = 100), DLB (n = 11) and non-PS (n = 89) after the DAT-SPECT and clinical follow-up. The patients underwent FP-CIT SPECT-CT 3-4 hours after the 167MBq tracer injection. The image data were reconstructed into two images, with CT attenuation correction and scatter correction (ACSC), and only with CT attenuation correction (CTSC). The SBR values for each patient were obtained using the Tossici-Bolt’s method (SBRBolt) and our new method. The new method extracted striatal VOI according to the high-level counts and the average volume of the striatum, and calculated the SBR using reference counts in the occipital lobes. Results: There were no difference in the mean age and gender in the three groups. The mean SBR values for the PS and DLB groups were significantly different from that of non-PS group. The two methods also showed significant differences each other. The coefficients of variation (CV) of the SBR were significantly smaller in the new method compared with those of SBRBolt (p < 0.0001, F-test) except for the CTAC reconstruction images. There were no differences in the SBR results between two operators if they used the new method. Conclusion: Our new method for SBR calculation in the FP-CIT SPECT showed less CV with high reproducibility, which would be useful in the clinical setting. View this table:SBR values for three groups and two methods