PT - JOURNAL ARTICLE AU - Hayakawa, Nobuyuki AU - Wakabayashi, Hiroshi AU - Werner, Rudolf AU - Javadi, Mehrbod AU - Lapa, Constantin AU - Higuchi, Takahiro TI - <sup>18</sup>F-fluorodeoxysorbitol PET as a Novel Functional Renal Imaging DP - 2016 May 01 TA - Journal of Nuclear Medicine PG - 538--538 VI - 57 IP - supplement 2 4099 - http://jnm.snmjournals.org/content/57/supplement_2/538.short 4100 - http://jnm.snmjournals.org/content/57/supplement_2/538.full SO - J Nucl Med2016 May 01; 57 AB - 538Objectives Accurate assessment of kidney function plays an essential role for optimal clinical decision-making in a variety of diseases. The intrinsic advantages of positron emission tomography (PET) could offer superior spatial and temporal resolutions for quantitative tomographic renal imaging. 2-deoxy-2-18F-fluorodeoxysorbitol (18F-FDS) is an analogue of sorbitol that is reported to be freely filtered at the renal glomerulus without re-absorption at the tubule. Furthermore, it can be synthesized via simple reduction of widely available 2-deoxy-2-18F-fluorodeoxyglucose (18F-FDG). We tested the feasibility of 18F-FDS renal PET imaging in rats.Methods Systemic and renal distribution of 18F-FDS was determined by dynamic 35min PET imaging (15 frames × 8 sec, 26 frames × 30 sec, 20 frames × 60 sec) with a dedicated small animal PET system (30 MBq, n=5) and post-mortem tissue counting (10 MBq, n=14) in healthy rats. Distribution of co-injected 99mTc-DTPA (1.5 MBq) was also estimated as a reference. Plasma binding and in-vivo stability of 18F-FDS were determined at 35 min after tracer administration.Results In-vivo PET imaging visualized rapid excretion of the administrated 18F-FDS from the both kidneys with minimal tracer accumulation in other organs. Initial cortical tracer uptake followed by visualization of the collecting system could be observed with high contrast. Split renography curves were successfully obtained in healthy rats (TmaxR = 2.8 ± 1.2 min, TmaxL = 2.9 ± 1.5 min, T1/2maxR = 8.8 ± 3.7 min, T1/2maxL = 11.1 ± 4.9 min). Post mortem tissue counting of 18F-FDS confirmed the high kidney extraction (kidney activities at 10, 30 and 60 min after tracer injection (%ID/g): 1.8 ± 0.7, 1.2 ± 0.1 and 0.5 ± 0.2, respectively) in a comparable degree to 99mTc-DTPA (2.5 ± 1.0, 1.5 ± 0.2 and 0.8 ± 0.3). Plasma protein binding of 18F-FDS was very low (&lt;0.1%), and metabolic transformation was not detected in serum and urine.Conclusions In rat experiments, 18F-FDS demonstrated high kidney excretion, low plasma protein binding and high metabolic stability as preferable properties for a renal imaging. These preliminary results warrant further confirmatory studies in large animal models and clinical studies as a novel renal imaging, given its advantages of PET technology and broad tracer availability.