Dataset Information

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [¹¹C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

ABSTRACT:

Introduction

Despite the decades long use of [¹¹C]palmitate positron emission tomography (PET)/computed tomography in basic metabolism studies, only personal communications regarding dosimetry and biodistribution data have been published.

Methods

Dosimetry and biodistribution studies were performed in 2 pigs and 2 healthy volunteers by whole-body [¹¹C]palmitate PET scans. Metabolite studies were performed in 40 participants (healthy and with type 2 diabetes) under basal and hyperinsulinemic conditions. Metabolites were estimated using 2 approaches and subsequently compared: Indirect [¹¹C]CO₂ release and parent [¹¹C]palmitate measured by a solid-phase extraction (SPE) method. Finally, myocardial fatty acid uptake was calculated in a patient cohort using input functions derived from individual metabolite correction compared with population-based metabolite correction.

Results

In humans, mean effective dose was 3.23 (0.02) µSv/MBq, with the liver and myocardium receiving the highest absorbed doses. Metabolite correction using only [¹¹C]CO₂ estimates underestimated the fraction of metabolites in studies lasting more than 20 minutes. Population-based metabolite correction showed excellent correlation with individual metabolite correction in the cardiac PET validation cohort.

Conclusion

First, mean effective dose of [¹¹C]palmitate is 3.23 (0.02) µSv/MBq in humans allowing multiple scans using ∼300 MBq [¹¹C]palmitate, and secondly, population-based metabolite correction compares well with individual correction.

SUBMITTER: Christensen NL

PROVIDER: S-EPMC5665104 | biostudies-literature | 2017 Jan-Dec

REPOSITORIES: biostudies-literature

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Publications

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [<sup>11</sup>C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

Christensen Nana L NL Jakobsen Steen S Schacht Anna C AC Munk Ole L OL Alstrup Aage K O AKO Tolbod Lars P LP Harms Hendrik J HJ Nielsen Søren S Gormsen Lars C LC

Molecular imaging 20170101

<h4>Introduction</h4>Despite the decades long use of [<sup>11</sup>C]palmitate positron emission tomography (PET)/computed tomography in basic metabolism studies, only personal communications regarding dosimetry and biodistribution data have been published.<h4>Methods</h4>Dosimetry and biodistribution studies were performed in 2 pigs and 2 healthy volunteers by whole-body [<sup>11</sup>C]palmitate PET scans. Metabolite studies were performed in 40 participants (healthy and with type 2 diabetes) ...[more]

PMID: 29073808

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Dataset Information

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [¹¹C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

Introduction

Methods

Results

Conclusion

Publications

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [<sup>11</sup>C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [11C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

Introduction

Methods

Results

Conclusion

Publications

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [<sup>11</sup>C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [¹¹C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism.