光學解析度光聲顯微系統有著非侵入式及高橫向解析度的優點，現今已被普遍應用在觀測小動物的血管成像上，並用取得的影像或數值，去計算不同的功能性參數。我們實驗室的雷射掃描式光學解析度光聲顯微系統已經能對受精後3~5天的斑馬魚幼魚進行血管造影。雖然這套系統有著成像速度快、空間解析度高的優點；但相對的，由於雷射焦點與超音波焦點沒有達到共焦，導致得到的影像訊雜比相對較低，而且成像範圍也受限於掃描視野的限制而較小。對應到斑馬魚幼魚的影像上，其背主動脈與後主靜脈的血管雖已有足夠影像對比度，但旁邊連接的微細小血管卻只能經由多次的重覆掃描，去做平均才能稍微顯露出來。對此，我們提出了機械掠掃式共軛焦光學解析度光聲顯微系統，希望經由達到雷射焦點與超音波焦點的共軛焦，來提升影像的訊雜比；而為了要達到共軛焦，掃描方式就只能改成機械式的由馬達去帶動，但是傳統的機械步進式掃描所花費的時間太長，對此我們改成機械掠掃式掃描，此方法能在馬達帶動探頭移動時，同時的觸發雷射出光並告知資料擷取卡同步接收光聲訊號，以大幅降低機械式掃描的執行時間。如此一來，或許就能在一次的掃描中，取得訊雜比相對較好的斑馬魚血管影像。

Optical-resolution photoacoustic microscopy (OR-PAM) system was often applied to observe the blood vessels of small animals because of its advantages such as non-invasive and high lateral resolution. In addition, the acquired images and data were used to calculate various functional parameters for different purposes. In our laboratory, we applied laser-scanning OR-PAM to image the blood vessels of the zebrafish larvae which were 3-5 days post fertilization (dpf). Although this system has the advantages of high frame rate and high spatial resolution, its signal-to-noise ratio (SNR) of the acquired image is not good because the laser focal point and ultrasonic focal point are not confocal. Furthermore, the imaging range was also limited by the field-of-view (FOV) of the transducer. For zebrafish images, though we could get the images of the dorsal aorta (DA) and posterior cardinal vein (PCV) with good image contrast, the signals of small vessels nearby the DA and PCV were not clear even by scanning and averaging for many times. Due to the weakness of the SNR, we proposed a mechanically swept-scanning confocal OR-PAM to get better SNR images in one scanning. We considered that the SNR of small vessel images could be improved by means of the confocal state between ultrasound and laser. However, the scanning mechanism must be replaced to the mechanically scanning due to the confocal requirement. We used the swept-scanning instead of the traditional step-scanning because we could trigger the laser emission and acquire the PA signals simultaneously while the motorized stage was moving. By this way, we could decrease the time wasted by the mechanical scanning.

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