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Near infrared and infrared multi-photon imaging through or inside bone is an emerging field that promises to help answer many biological questions that require minimally invasive intravital imaging. Neuroscience researchers especially have begun to take advantage of long wavelength imaging to overcome multiple scattering and image deep inside the brain through intact or partially intact bone. Since the murine model is used in many biological experiments, here we investigate the optical aberrations caused by mouse cranial bone, and their effects on light propagation. We previously developed a ray tracing model that uses second harmonic generation in collagen fibers of bone to estimate the refractive index structure of the sample. This technique is able to rapidly provide initial information for a closed loop adaptive optics system. However, the ray tracing method does not account for refraction or scattering. Here, we extend our work to investigate the wavefront aberrations in bone using a full electromagnetic model. We used Finite-Difference Time-Domain modeling of light propagation in refractive index bone datasets acquired with second harmonic generation imaging. In this paper we show modeled wavefront phase from different originating points across the field of view.
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Intravital multi-photon imaging through intact highly scattering bone using binary wavefront optimization
Diffraction limited imaging of structures in a highly scattering heterogeneous tissue like bone is a non-trivial task. Here we show binary wavefront optimization using a genetic algorithm, for 2-photon imaging of bone endogenous cells.
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- Award ID(s):
- 1706916
- PAR ID:
- 10099734
- Date Published:
- Journal Name:
- Imaging and Applied Optics 2018 (3D, AO, AIO, COSI, DH, IS, LACSEA, LS&C, MATH, pcAOP), OSA Technical Digest (Optical Society of America, 2018)
- Page Range / eLocation ID:
- JTu5B.2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/3D.2018.JTu5B.2
