Single-breath-hold photoacoustic computed tomography of the breast

TLDR

We developed a single‑breath‑hold photoacoustic computed tomography (SBH‑PACT) system to image detailed breast angiography. SBH‑PACT provides 4 cm penetration, 255 µm resolution, and a 10 Hz frame rate, scans the entire breast in ~15 s during a single breath hold, reconstructs 3‑D volumes with back‑projection, enables dynamic elastography, and has been applied to patients ranging from B to DD cup sizes and various skin tones. In breast cancer patients, SBH‑PACT detected all tumors by highlighting increased vascular density, demonstrated high sensitivity in dense breasts, and did so without ionizing radiation or exogenous contrast, posing no health risks.

Abstract

We have developed a single-breath-hold photoacoustic computed tomography (SBH-PACT) system to reveal detailed angiographic structures in human breasts. SBH-PACT features a deep penetration depth (4 cm in vivo) with high spatial and temporal resolutions (255 µm in-plane resolution and a 10 Hz 2D frame rate). By scanning the entire breast within a single breath hold (~15 s), a volumetric image can be acquired and subsequently reconstructed utilizing 3D back-projection with negligible breathing-induced motion artifacts. SBH-PACT clearly reveals tumors by observing higher blood vessel densities associated with tumors at high spatial resolution, showing early promise for high sensitivity in radiographically dense breasts. In addition to blood vessel imaging, the high imaging speed enables dynamic studies, such as photoacoustic elastography, which identifies tumors by showing less compliance. We imaged breast cancer patients with breast sizes ranging from B cup to DD cup, and skin pigmentations ranging from light to dark. SBH-PACT identified all the tumors without resorting to ionizing radiation or exogenous contrast, posing no health risks.