Photoacoustic angiography for mouse brain cortex using near-infrared light

Photoacoustic imaging is a novel noninvasive imaging technique of biological tissue that overcomes the overwhelming scattering of light in biological tissue by utilizing ultrasonic wave to translate the image signal. In this study, near-infrared light and indocyanine green as an optical contrast agent were used to achieve the cerebrovascular distribution by photoacoustic imaging. Near-infrared light penetrates deep into the brain tissues through the skin and skull, and the indocyanine green enhances the photoacoustic signals of the blood vessels. A photoacoustic angiography of vascular distribution in the mouse brain in vivo was acquired that matches the anatomical photograph well. The experimental result demonstrates the photoacoustic imaging with near-infrared light and optical contrast agent has the potential for functional and molecular biomedical imaging.