Yang Jianlong, Liu Liang, Campbell J Peter, Huang David, Liu Gangjun
Casey Eye Institute, Oregon Health and Science University, 3375 SW Terwilliger Blvd, Portland, OR 97239, USA.
Biomed Opt Express. 2017 Mar 22;8(4):2287-2300. doi: 10.1364/BOE.8.002287. eCollection 2017 Apr 1.
We developed a handheld optical coherence tomography angiography (OCTA) system using a 100-kHz swept-source laser. The handheld probe weighs 0.4 kg and measures 20.6 × 12.8 × 4.6 cm. The system has dedicated features for handheld operation. The probe is equipped with a mini iris camera for easy alignment. Real-time display of the OCT and cross-sectional OCT images in the system allows accurately locating the imaging target. Fast automatic focusing was achieved by an electrically tunable lens controlled by a golden-section search algorithm. An extended axial imaging range of 6 mm allows easy alignment. A registration algorithm using cross-correlation to register adjacent OCT B-frames with propagation from the central frame was used to effectively minimize motion artifacts in volumetric OCTA images captured in relatively short durations of 1 and 2.1 seconds. 2.5 × 2.5 mm (200 × 200 pixels) and 3.5 × 3.5 mm (300 × 300 pixels) retinal angiograms were demonstrated on two awake adult human subjects without the use of any mydriatic eye drops.
我们使用100kHz扫频光源激光器开发了一种手持式光学相干断层扫描血管造影（OCTA）系统。该手持式探头重0.4kg，尺寸为20.6×12.8×4.6cm。该系统具有专门用于手持式操作的功能。探头配备了一个小型虹膜相机，便于对准。系统中OCT和横截面OCT图像的实时显示可精确确定成像目标的位置。通过由黄金分割搜索算法控制的电可调透镜实现了快速自动聚焦。6mm的扩展轴向成像范围便于对准。使用互相关来配准相邻OCT B帧并从中心帧进行传播的配准算法，用于有效减少在1秒和2.1秒的相对短时间内采集的体积OCTA图像中的运动伪影。在两名清醒的成年人类受试者上展示了2.5×2.5mm（200×200像素）和3.5×3.5mm（300×300像素）的视网膜血管造影，且未使用任何散瞳眼药水。
