Development of a minimally invasive simultaneous estimation method for quantifying translocator protein binding with [18F]FEPPA positron emission tomography

EJNMMI Research

Original Research

Praveen Dassanayake¹  Justin Hicks¹  Keith St Lawrence¹  Lucas Narciso¹  Udunna C. Anazodo²  Pablo Rusjan³  Linshan Liu⁴  Maryssa Iacobelli⁴  Elizabeth Finger⁵ 

[1] Department of Medical Biophysics, University of Western Ontario, London, ON, Canada;Lawson Health Research Institute, 268 Grosvenor St, N6A 4V2, London, ON, Canada;Department of Medical Biophysics, University of Western Ontario, London, ON, Canada;Lawson Health Research Institute, 268 Grosvenor St, N6A 4V2, London, ON, Canada;Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada;Douglas Research Centre, Human Neuroscience Division, Montréal, QC, Canada;Department of Psychiatry, McGill University, Montréal, QC, Canada;Lawson Health Research Institute, 268 Grosvenor St, N6A 4V2, London, ON, Canada;Lawson Health Research Institute, 268 Grosvenor St, N6A 4V2, London, ON, Canada;Department of Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada;

关键词: Positron emission tomography;    PET/MR;    Translocator protein (TSPO) imaging;    Simultaneous estimation method;    Kinetic modeling;    Image-derived input function;   

DOI  :  10.1186/s13550-023-00950-1

 received in 2022-10-04, accepted in 2023-01-01,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundThe purpose of this study was to assess the feasibility of using a minimally invasive simultaneous estimation method (SIME) to quantify the binding of the 18-kDa translocator protein tracer [18F]FEPPA. Arterial sampling was avoided by extracting an image-derived input function (IDIF) that was metabolite-corrected using venous blood samples. The possibility of reducing scan duration to 90 min from the recommended 2–3 h was investigated by assuming a uniform non-displaceable distribution volume (VND) to simplify the SIME fitting.ResultsSIME was applied to retrospective data from healthy volunteers and was comprised of both high-affinity binders (HABs) and mixed-affinity binders (MABs). Estimates of global VND and regional total distribution volume (VT) from SIME were not significantly different from values obtained using a two-tissue compartment model (2CTM). Regional VT estimates were greater for HABs compared to MABs for both the 2TCM and SIME, while the SIME estimates had lower inter-subject variability (41 ± 17% reduction). Binding potential (BPND) values calculated from regional VT and brain-wide VND estimates were also greater for HABs, and reducing the scan time from 120 to 90 min had no significant effect on BPND. The feasibility of using venous metabolite correction was evaluated in a large animal model involving a simultaneous collection of arterial and venous samples. Strong linear correlations were found between venous and arterial measurements of the blood-to-plasma ratio and the remaining [18F]FEPPA fraction. Lastly, estimates of BPND and the specific distribution volume (i.e., VS = VT − VND) from a separate group of healthy volunteers (90 min scan time, venous-scaled IDIFs) agreed with estimates from the retrospective data for both genotypes.ConclusionsThe results of this study demonstrate that accurate estimates of regional VT, BPND and VS can be obtained by applying SIME to [18F]FEPPA data. Furthermore, the application of SIME enabled the scan time to be reduced to 90 min, and the approach worked well with IDIFs that were scaled and metabolite-corrected using venous blood samples.

【 授权许可】

CC BY   
© The Author(s) 2023

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