Three-dimensional photoacoustic imaging of blood vessels in tissue

TLDR

We applied photoacoustics as a tissue tomography technique to detect blood concentrations, such as angiogenesis around tumors. Using 532‑nm light, we imaged blood vessels in highly scattering samples (chicken breast or 10 % Intralipid‑10%) to ~1 cm depth, with blood flowing through nylon capillaries, and detected signals with surface‑scanning PVdF piezoelectric detectors. The technique detected single red blood cells on a glass plate, achieving a lateral resolution limited to 200 µm and a depth resolution of about 10 µm.

Abstract

We applied photoacoustics as a tissue tomography technique for the detection of blood concentrations, e.g., angiogenesis around tumors. We imaged blood vessels in highly scattering samples, using 532-nm light, to depths of ~1 cm . The samples were real tissue (chicken breast) or 10% dilutions of Intralipid-10%. The blood flowed through nylon capillaries. Polyvinylidene difluoride (PVdF) piezoelectric detectors were used in a surface-scanning mode. We demonstrate the sensitivity of the technique by photoacoustic detection of single red blood cells upon a glass plate. Lateral resolution is limited by the detector diameter (200 microm). The depth resolution is ~10 microm.