Abstract

Photoacoustic (PA) imaging is a promising biomedical imaging modality, which can simultaneously offer anatomical, molecular and functional high-resolution imaging at clinically relevant penetration depths in vivo [1]. In PA imaging, pulsed light is introduced into tissues and gets absorbed by endogenous chromophores such as hemoglobin and melanin, or exogenous contrast agents. This results in thermoelastic tissue expansion, generating acoustic waves which can be captured by ultrasound detectors for image reconstruction. Up to date, various exogenous contrast agents such as carbon nanotubes [2], gold nanorods [3] and near-infrared dyes like indocyanine green [4] have been explored to enhance the imaging contrast. However, the clinical application of these probes has been limited due to cytotoxicity issues.

© 2014 Optical Society of America