Puyo L, Paques M, Fink M, Sahel J-A, Atlan M
Institut Langevin, Centre National de la Recherche Scientifique (CNRS), Paris Sciences & Lettres (PSL Research University), École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris) - 1 rue Jussieu, 75005 Paris, France.
Institut de la Vision, INSERM UMR-S 968, CNRS UMR 7210, UPMC, 17 rue Moreau, 75012 Paris, France.
Biomed Opt Express. 2018 Aug 6;9(9):4113-4129. doi: 10.1364/BOE.9.004113. eCollection 2018 Sep 1.
The eye offers a unique opportunity for the non-invasive exploration of cardiovascular diseases. Optical angiography in the retina requires sensitive measurements, which hinders conventional full-field laser Doppler imaging schemes. To overcome this limitation, we used digital holography to perform laser Doppler perfusion imaging of human retina with near-infrared light. Two imaging channels with a slow and a fast CMOS camera were used simultaneously for real-time narrowband measurements, and offline wideband measurements, respectively. The beat frequency spectrum of optical interferograms recorded with the fast (up to 75 kHz) CMOS camera was analyzed by short-time Fourier transformation. Power Doppler images drawn from the Doppler power spectrum density qualitatively revealed blood flow in retinal vessels over 512 × 512 pixels covering 2.4 × 2.4 mm on the retina with a temporal resolution down to 1.6 ms. The sensitivity to lateral motion as well as the requirements in terms of sampling frequency are discussed.
眼睛为心血管疾病的非侵入性探测提供了独特的机会。视网膜中的光学血管造影需要进行灵敏测量，这阻碍了传统的全场激光多普勒成像方案。为克服这一限制，我们利用数字全息术，使用近红外光对人视网膜进行激光多普勒灌注成像。两个成像通道分别与一个慢速和一个快速互补金属氧化物半导体（CMOS）相机同时使用，用于实时窄带测量和离线宽带测量。用快速（高达75千赫兹）CMOS相机记录的光学干涉图的拍频光谱通过短时傅里叶变换进行分析。从多普勒功率谱密度得出的功率多普勒图像定性地揭示了视网膜血管中的血流情况，覆盖视网膜上2.4×2.4毫米的512×512像素区域，时间分辨率低至1.6毫秒。文中还讨论了对横向运动的灵敏度以及采样频率方面的要求。
