Multiwavelength Laser Diode based Portable Photoacoustic and Ultrasound
Imaging System for Point of Care Applications
Abstract
Vascular diseases are a leading cause of death and disability
worldwide. Despite having precursor conditions like peripheral arterial
disease (PAD), they are often only diagnosed after the onset of strokes
or heart attacks. Low-cost, portable, non-invasive, point-of-care (POC)
assessment of deep vascular function benefits PAD diagnosis, especially
in low-and-middle-income countries. Doppler ultrasound-based blood flow
measurements can diagnose PAD, albeit, with limited sensitivity and
specificity. To overcome this, here, we propose the first-of-its-kind
photoacoustic-and-ultrasound (PAUS) imaging system that integrates a
multiwavelength pulsed laser diode (PLD) with a compact ultrasound data
acquisition system. The portable PLD-PAUS system was validated for deep
tissue imaging using tissue phantoms, and for multispectral
photoacoustic imaging using an atherosclerosis mimicking phantom.
Further, we demonstrated high-contrast volumetric in-vivo photoacoustic
imaging of rodent abdominal vasculature and quantified vessel reactivity
due to hypercapnia stimulation. The multiparametric functional and
molecular imaging capabilities of the PLD-PAUS system holds promise for
POC applications.
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