Intravital photoacoustic microscopy of microvascular function and oxygen metabolism

Dysfunction of microvascular function and tissue oxygen metabolism has long been associated with a wide range of human diseases, including cardiovascular disease, neurovascular disease, diabetes, and cancer. Capitalizing on the light absorption of blood hemoglobin, photoacoustic microscopy (PAM) has emerged as a promising new technology for high-resolution, label-free, functional-metabolic imaging of the microvasculature in live animals and humans. In this chapter, we introduce multiple different PAM approaches and detailed methodologies for microvascular imaging in both the superficial skin and internal organs. We also review current and potential biomedical applications. Besides, the frontiers of intravital PAM imaging of microvascular function and oxygen metabolism are discussed.