Mesoscopic calcium imaging enables studies of cell-type specific neural activity over large areas. A growing body of literature suggests that neural activity can be different when animals are free to move compared to when they are restrained. Unfortunately, existing systems for imaging calcium dynamics over large areas in non-human primates (NHPs) are table-top devices that require restraint of the animal’s head. Here, we demonstrate an imaging device capable of imaging mesoscale calcium activity in a head-unrestrained male non-human primate. We successfully miniaturize our system by replacing lenses with an optical mask and computational algorithms. The resulting lensless microscope can fit comfortably on an NHP, allowing its head to move freely while imaging. We are able to measure orientation columns maps over a 20 mm2field-of-view in a head-unrestrained macaque. Our work establishes mesoscopic imaging using a lensless microscope as a powerful approach for studying neural activity under more naturalistic conditions.
The combination of nonhuman primates (NHPs) with the state‐of‐the‐art molecular imaging technologies allows for within‐subject longitudinal research aiming at gaining new insights into human normal and disease conditions and provides an ideal foundation for future translational studies of new diagnostic tools, medical interventions, and therapies. However, radiation dose estimations for nonhuman primates from molecular imaging probes are lacking and are difficult to perform experimentally. The aim of this work is to construct age‐dependent NHP computational model series to estimate the absorbed dose to NHP specimens in common molecular imaging procedures.
A series of NHP models from baby to adult were constructed based on nonuniform rational B‐spline surface (NURBS) representations. Particle transport was simulated using Monte Carlo calculations to estimate S‐values from nine positron‐emitting radionuclides and absorbed doses from PET radiotracers.
Realistic age‐dependent NHP computational model series were developed. For most source‐target pairs in computational NHP models, differences between C‐11 S‐values were between −13.4% and −8.8%/kg difference in body weight while differences between F‐18 S‐values were between −12.9% and −8.0%/kg difference in body weight. The absorbed doses of11C‐labeled brain receptor substances,18F‐labeled brain receptor substances, and18F‐FDG in the brain ranged within 0.047–0.32 mGy/MBq, 0.25–1.63 mGy/MBq, and 0.32–2.12 mGy/MBq, respectively.
The absorbed doses to organs are significantly higher in the baby NHP model than in the adult model. These results can be used in translational longitudinal studies to estimate the cumulated absorbed organ doses in NHPs at various ages.
- NSF-PAR ID:
- 10455094
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Medical Physics
- Volume:
- 47
- Issue:
- 9
- ISSN:
- 0094-2405
- Page Range / eLocation ID:
- p. 4465-4476
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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