Single-shot 3D photoacoustic tomography using a single-element detector for ultrafast imaging of hemodynamics
Abstract
Imaging hemodynamics is crucial for the diagnosis, treatment, and prevention of vascular diseases, particularly for identifying vascular dysfunction in peripheral vascular disease and diabetes patients, monitoring blood supply in lower extremities, and assisting in the management of chronic conditions like leg ulcers with underlying vascular insufficiency. However, current imaging techniques are limited due to the use of ionizing radiation or contrast agents, short penetration depth, or complex and expensive data acquisition systems. Photoacoustic tomography shows promise as a solution to these issues. However, existing photoacoustic tomography methods collect signals either sequentially or through numerous detector elements, leading to either low imaging speed or high system complexity and cost. To address these issues, here we introduce a method to capture a 3D photoacoustic image of vasculature using a single laser pulse and a single-element detector that functions as 6,400 virtual ones. Our method enables ultrafast volumetric imaging of hemodynamics in the human body at up to 1 kHz and requires only a single calibration for different objects and for long-term operations. We demonstrate 4D imaging of hemodynamics at depth in humans and small animals, capturing the variability in blood flow speeds. In particular, we capture 4D hemodynamic changes in human foot vessels in response to vascular occlusion, demonstrating clinical potential in early detection and treatment monitoring of peripheral vascular diseases, providing detailed and localized insights into vascular function that can guide effective patient care and treatment decisions. Finally, the concept of single-shot 3D imaging using a single-element detector can inspire other imaging technologies and find applications such as home-care monitoring, biometrics, point-of-care testing, and wearable monitoring.
Yide Zhang
Postdoctoral Scholar
My research is interdisciplinary and focused on developing new types of optical imaging techniques that could advance the work of other researchers and medical personnel in a wide variety of fields. Currently, I am developing next-generation photoacoustic and ultrafast imaging techniques that can observe biological and physical phenomena that are too fast to be imaged with existing methods. The observation of the ultrafast phenomena could provide a better understanding of the fundamentals of life and physical sciences. I am also developing novel quantum imaging approaches that can investigate biological organisms with an imaging performance that cannot be achieved using classical optical imaging. In my free time, I enjoy cooking, hiking, cycling, and traveling.