光學同調斷層掃描在生醫光學領域中是一項非常有潛力的造影技術，此技術被廣泛應於眼科、腸胃科等。由於頻域式光學同調斷層掃描與光聲顯微術擁有相同的掃瞄機制，近年來已經有研究團隊開發出頻域式光學同調斷層掃描與雷射掃描式光聲顯微術結合，然而為了要增加光聲顯微術的掃描視野(field of view)，光聲顯微術通常使用非聚焦式的超音波探頭，但使用非聚焦式的超音波探頭訊雜比(signal-to-noise ratio)較差且會產生空間脈衝響應(spatial impulse response)，此效應會造成軸向解析度變差並且降低高頻超音波探頭應用在功能性影像上的效果。為了解決這個問題，我們之前的研究在光聲顯微鏡提出一個「虛擬點偵測器」概念，此概念可以同時增加訊雜比、降低空間脈衝響應，還能獲得足夠的掃描視野。在這項研究中，我們建立一個頻域式光學同調斷層掃描並與基於虛擬點偵測器概念之雷射掃描式光聲顯微鏡整合來提供在生物組織上影像的光散射和光吸收對比。我們所整合的系統其光聲顯微術的橫向解析度為7.81 μm，軸向解析度為68.2 μm，而光學同調斷層掃瞄之橫向解析度為6.20 μm，軸向解析度為15.8 μm。相較於光聲顯微鏡的軸向解析度，光學同調斷層掃描具有優異的軸向解析度。因此除了影像對比互補外，光學同調斷層掃描可以補足光聲影像不足的深度解析資訊。

Optical coherence tomography is a promising biomedical imaging technique, which is widely used in ophthalmology and gastroenterology, etc. In recent years, there are several groups developing Fourier domain optical coherence tomography integrated with laser scanning photoacoustic microscopy since the Fourier domain optical coherence tomography and photoacoustic microscopy have the same scanning mechanism. However, in order to increase the field of view (FOV) of photoacoustic microscopy that it commonly uses an unfocused ultrasonic transducer. The signal-to-noise ratio (SNR) of unfocused ultrasonic transducer is poor and produces a spatial impulse response (SIR) effect, which can lead to deteriorate axial resolution and impede the use of the high frequency and broadband transducer required for functional imaging applications. In order to solve this problem, our previous study has developed a virtual point detector concept for the photoacoustic microscope system that it can increase the signal-to-noise ratio, reduce the space impulse response, and obtain enough scanning field of view at the same time. In this study, we build a spectral-domain optical coherence tomography (SD-OCT) integrated with virtual point detector concept based laser scanning optical-resolution photoacoustic microscopy (OR-PAM) to provide microscopic imaging with both optical scattering and absorption contrast in biological tissues. Currently, the integrated system can provide 7.81 μm lateral and 68.2 μm axial resolution for OR-PAM and 6.20 μm lateral and 15.8 μm axial resolution for SD-OCT. The SD-OCT has much better axial resolution than the OR-PAM so that in addition to complementary image contrast, the SD-OCT can complement the depth resolving capability of the OR-PAM.

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