Continuous wave laser excitation based portable optoacoustic imaging system for melanoma detection

Abstract

Optoacoustic imaging has been demonstrated successfully in detecting cutaneous melanoma in its early stage. In this work, we develop a handheld optoacoustic based portable medical imaging system for early melanoma diagnosis. In the portable optoacoustic system, laser excitation is provided by a compact continuous wave laser diode, which is driven by an FPGA controlled Howland circuit driver board. Optoacoustic detection is performed using a 2D square ultrasound transducer array and a portable multichannel data acquisition system. To pursue the optimized imaging SNR and resolution, chirp modulated laser excitation and matched filtering based acoustic pulse compression are further incorporated. To evaluate the feasibility of imaging melanoma, multisite 3D imaging on a human breast phantom is handheld performed. The prospect of using low-cost continuous wave laser diode and matrix array ultrasound transducers for volumetric optoacoustic imaging would be a real breakthrough towards commercialization of the optoacoustic technique.