title: Concurrent photoacoustic-ultrasound imaging using single-laser pulses.
abstract: Conventional ultrasound (US) and photoacoustic (PA) multimodality imaging require the use of a US pulse for US data acquisition and a laser pulse for PA data acquisition. We propose a method for concurrent US and PA data acquisition with a single-laser pulse. A light-absorbing multilayer film that can generate a US pulse based on the thermoelastic effect is used. The selection of appropriate layer thickness, interlayer spacing, and absorption coefficient allows the spectral characteristics of the generated US signal to be adjusted so that it does not overlap with the spectrum of the PA signal generated by the light transmitting through the layer. Thus, the US signal and the PA signal can be generated, received, and separated by using a single-laser pulse combined with spectral filtering. This method is demonstrated using a multilayer film that generates US signals with a center frequency of 24.2 MHz and fractional bandwidth of 26.8%. The synthetic-aperture focusing technique is applied to improve the lateral resolution and the signal-to-noise ratio. A cyst-like phantom and a film phantom were used to demonstrate the feasibility of this method of concurrent PA-US imaging using single-laser pulses.
authors.affiliation: National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan.
authors.forename: Shi-Yao
authors.initials: SY
authors.lastname: Hung
authors.affiliation: National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan.
authors.forename: Wen-Shao
authors.initials: WS
authors.lastname: Wu
authors.affiliation: National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan.
authors.forename: Bao-Yu
authors.initials: BY
authors.lastname: Hsieh
authors.affiliation: National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1, Sec. 4, Roosevelt Road, Taipei 106, TaiwanbNational Taiwan University, Department of Electrical Engineering, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Tai.
authors.forename: Pai-Chi
authors.initials: PC
authors.lastname: Li
mesh_terms: D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D007834:Lasers; D064847:Multimodal Imaging / Q000295:instrumentation*; D019047:Phantoms, Imaging; D061088:Photoacoustic Techniques / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*