Malone Joseph D, El-Haddad Mohamed T, Yerramreddy Suhaas S, Oguz Ipek, Tao Yuankai K
Vanderbilt University, Department of Biomedical Engineering, Nashville, Tennessee, United States.
Vanderbilt University, Department of Electrical Engineering and Computer Science, Nashville, Tennessee, United States.
Neurophotonics. 2019 Oct;6(4):041102. doi: 10.1117/1.NPh.6.4.041102. Epub 2019 Jul 3.
Optical coherence tomography (OCT) is the gold standard for quantitative ophthalmic imaging. The majority of commercial and research systems require patients to fixate and be imaged in a seated upright position, which limits the ability to perform ophthalmic imaging in bedridden or pediatric patients. Handheld OCT devices overcome this limitation, but image quality often suffers due to a lack of real-time aiming and patient eye and photographer motion. We describe a handheld spectrally encoded coherence tomography and reflectometry (SECTR) system that enables simultaneous reflectance and cross-sectional OCT imaging. The handheld probe utilizes a custom double-pass scan lens for fully telecentric OCT scanning with a compact optomechanical design and a rapid-prototyped enclosure to reduce the overall system size and weight. We also introduce a variable velocity scan waveform that allows for simultaneous acquisition of densely sampled OCT angiography (OCTA) volumes and widefield reflectance images, which enables high-resolution vascular imaging with precision motion-tracking for volumetric motion correction and multivolumetric mosaicking. Finally, we demonstrate human retinal OCT and OCT angiography (OCTA) imaging using handheld SECTR on a healthy volunteer. Clinical translation of handheld SECTR will allow for high-speed, motion-corrected widefield OCT and OCTA imaging in bedridden and pediatric patients who may benefit ophthalmic disease diagnosis and monitoring.
光学相干断层扫描（OCT）是眼科定量成像的金标准。大多数商业和研究系统要求患者固定并以坐姿直立进行成像，这限制了对卧床或儿科患者进行眼科成像的能力。手持式OCT设备克服了这一限制，但由于缺乏实时瞄准以及患者眼睛和摄影师的移动，图像质量往往会受到影响。我们描述了一种手持式光谱编码相干断层扫描和反射测量（SECTR）系统，该系统能够同时进行反射率和横截面OCT成像。手持式探头采用定制的双程扫描透镜，用于全远心OCT扫描，具有紧凑的光机械设计和快速成型的外壳，以减小整个系统的尺寸和重量。我们还引入了可变速度扫描波形，可同时采集密集采样的OCT血管造影（OCTA）容积和宽视野反射率图像，从而实现高分辨率血管成像，并通过精确的运动跟踪进行容积运动校正和多容积拼接。最后，我们展示了在一名健康志愿者身上使用手持式SECTR进行的人体视网膜OCT和OCT血管造影（OCTA）成像。手持式SECTR的临床应用将允许对卧床和儿科患者进行高速、运动校正的宽视野OCT和OCTA成像，这可能有助于眼科疾病的诊断和监测。
