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In vivo photothermal optical coherence tomography of endogenous and exogenous contrast agents in the eye.

ABSTRACT: Optical coherence tomography (OCT) has become a standard-of-care in retinal imaging. OCT allows non-invasive imaging of the tissue structure but lacks specificity to contrast agents that could be used for in vivo molecular imaging. Photothermal OCT (PT-OCT) is a functional OCT-based technique that has been developed to detect absorbers in a sample. We demonstrate in vivo PT-OCT in the eye for the first time on both endogenous (melanin) and exogenous (gold nanorods) absorbers. Pigmented mice and albino mice (n?=?6 eyes) were used to isolate the photothermal signal from the melanin in the retina. Pigmented mice with laser-induced choroidal neovascularization lesions (n?=?7 eyes) were also imaged after a systemic injection of gold nanorods to observe their passive accumulation in the retina. This experiment demonstrates the feasibility of PT-OCT to image the distribution of both endogenous and exogenous absorbers in the mouse retina.

SUBMITTER: Lapierre-Landry M

PROVIDER: S-EPMC5569082 | biostudies-other | 2017 Aug

REPOSITORIES: biostudies-other

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In vivo photothermal optical coherence tomography of endogenous and exogenous contrast agents in the eye.

Lapierre-Landry Maryse M Gordon Andrew Y AY Penn John S JS Skala Melissa C MC

Scientific reports 20170823 1

Optical coherence tomography (OCT) has become a standard-of-care in retinal imaging. OCT allows non-invasive imaging of the tissue structure but lacks specificity to contrast agents that could be used for in vivo molecular imaging. Photothermal OCT (PT-OCT) is a functional OCT-based technique that has been developed to detect absorbers in a sample. We demonstrate in vivo PT-OCT in the eye for the first time on both endogenous (melanin) and exogenous (gold nanorods) absorbers. Pigmented mice and ...[more]

PMID: 28835698

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