非侵入性光學共軛斷層血管掃描儀－原理介紹及臨床運用

10.6666/ClinMed.201805_81(5).0053

黃怡銘；陳世真

光學共輒斷層掃描儀(OCT) ； 光學共輒斷層血管掃描儀(OCTA) ； 分光譜去相關血管成像法(split-spectrum amplitude-decorrelation angiography, SSADA)

臨床醫學月刊

81卷5期（2018 / 05 / 25）

290 - 295

繁體中文

光學共輒斷層掃描儀(Optical Coherence Tomography, OCT)在眼科領域的使用已經將近有十多年。而非侵入性光學共軛斷層血管掃描儀(OCT angiography, OCTA)是一種光學共輒斷層掃描儀的進化版，並且已經快速被應用於眼科。OCT的原理類似超音波，只是以光線取代超音波，並加上干涉儀，因此可以逐層取得視網膜的光線反向散射(backscattering)，組成縱向橫斷面的結構，也可以組合出橫向的en face圖。因為反向散射光線的強度(intensity)及相位(phase)會受到視網膜組織的內在移動(例如，血管內紅血球移動)而使反射的光線，相對於靜止的組織(例如，視網膜結構)而有所不同。OCTA的影像就是擷取這些移動對比(motion-contrast)的訊息，而產生的非侵入性血管造影圖。因此，OCTA可以顯示許多眼科疾病重要的發現，包含缺血(impaired perfusion)、微動脈瘤(microaneurysms)和新生血管。目前，非侵入性光學共輒斷層血管掃描儀已經廣泛的運用在視網膜血管疾病的診斷和治療評估，包含糖尿病視網病變、視網膜動靜脈阻塞、葡萄膜炎、老年性黃斑部病變等等。

1. Adhi, M,Filho, MA,Louzada, RN(2016).Retinal Capillary Network and Foveal Avascular Zone in Eyes with Vein Occlusion and Fellow Eyes Analyzed With Optical Coherence Tomography Angiography.Invest Ophthalmol Vis Sci,57,486-494.
2. Bruyère, E,Miere, A,Cohen, SY(2017).Neovascularization secondary to high myopia imaged by optical coherence tomography angiography.Retina,37,2095-2101.
3. Hasegawa, N,Nozaki, M,Takase, N(2016).New Insights Into Microaneurysms in the Deep Capillary Plexus Detected by Optical Coherence Tomography Angiography in Diabetic Macular Edema.Invest Ophthalmol Vis Sci,57,348-355.
4. Huang, D,Swanson, EA,Lin, CP(1991).Optical coherence tomography.Science,254,1176-1181.
5. Huang, Yi-Ming,Hsieh, Ming-Hung,Li, An-Fei(2017).Sensitivity, Specificity, and Limitations of Optical Coherence Tomography Angiography in Diagnosis of Polypoidal Choroidal Vasculopathy.J Ophthalmol,2017,3479695.
6. Kashani, AH,Chen, CL,Gahm, JK(2017).Optical coherence tomography angiography: A comprehensive review of current methods and clinical applications.Prog Retin Eye Res,60,66-100.
7. Sambhav, Kumar,Grover, Sandeep,Chalam, Kakarla V.(2017).The application of optical coherence tomography angiography in retinal diseases.Surv Ophthalmol,62,838-866.
8. Tan, ACS,Tan, GS,Denniston, AK(2018).An overview of the clinical applications of optical coherence tomography angiography.Eye,32,262-286.