Dovlo Edem, Lashkari Bahman, Mandelis Andreas, Shi Wei, Liu Fei-Fei
Center for Advanced Diffusion-Wave Technologies (CADIFT), Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada.
Ontario Cancer Institute, Princess Margaret Hospital, 610 University Ave., Toronto, ON M5G 2M9, Canada.
Biomed Opt Express. 2015 Feb 25;6(3):1003-9. doi: 10.1364/BOE.6.001003. eCollection 2015 Mar 1.
Co-registered ultrasound (US) and frequency-domain photoacoustic radar (FD-PAR) imaging is reported for the first time in this paper. The merits of ultrasound and cross-correlation (radar) frequency-domain photoacoustic imaging are leveraged for accurate tumor detection. Commercial US imagers possess sophisticated, optimized software for rapid image acquisition that could dramatically speed-up PA imaging. The PAR image generated from the amplitude of the cross-correlation between detected and input signals was filtered by the standard deviation (SD) of the phase of the correlation signal, resulting in strong improvement of image spatial resolution, signal-to-noise ratio (SNR) and contrast. Application of phase-mediated image improvement is illustrated by imaging a cancer cell-injected mouse. A 14-15 dB SNR gain was recorded for the phase-filtered image compared to the amplitude and phase independently, while ~340 μm spatial resolution was seen for the phase PAR image compared to ~840 μm for the amplitude image.
本文首次报道了联合注册超声（US）和频域光声雷达（FD-PAR）成像。利用超声和互相关（雷达）频域光声成像的优点进行准确的肿瘤检测。商用超声成像仪拥有复杂、优化的软件用于快速图像采集，这可以显著加快光声成像速度。由检测信号与输入信号之间的互相关幅度生成的PAR图像通过相关信号相位的标准差（SD）进行滤波，从而显著提高了图像空间分辨率、信噪比（SNR）和对比度。通过对注射癌细胞的小鼠进行成像来说明相位介导的图像改善的应用。与幅度和相位独立成像相比，相位滤波图像的SNR增益为14-15 dB，而相位PAR图像的空间分辨率约为340μm，幅度图像的空间分辨率约为840μm。
