Abstract
Purpose :
OCT and OCT angiography (OCTA) are valuable techniques that have improved the diagnosis and management of various ocular diseases in adults but rarely practiced on young children and infants due to its limitations. We report the novel design and operation of a highly integrated miniature handheld OCT probe, with high-speed angiography function that can be used in clinical settings for young children and infants.
Methods :
Laboratory prototype swept source OCT (SS-OCT) system; A-line scan rate: 200 kHz, frame rate: 400Hz, axial resolution: 8.2 μm. An ultra-compact handheld probe, with view-finder camera and on-probe screen is designed and fabricated, as shown in Figure 1(a). This highly integrated probe provides the operator with rich visual feedback including real-time OCT image and iris image. This facilitates the rapid targeting of the probe to young children and infants, without looking away at computer screen. The imaging system provides high-resolution and high frame rate structural images and angiography results. A new algorithm rejects OCTA artefacts from involuntary motions and enhances imaging quality and speed.
Results :
Healthy volunteers were imaged for both eyes. The maximum imaging area on human retina is 9 × 9 mm2. Typical image acquisition time for a structural 3D imaging is <1 second, and OCTA 3D imaging is ~2 seconds, benefiting from the fast A-line scan rate. The hand-held OCTA results demonstrates the capability to resolve all retinal vessels down to capillary level, as depicted in Figure 1(b). Compared to conventional computer monitor, the on-probe display significantly improved the convenience and efficiency of the operator and enables the monitoring of imaging subject simultaneously.
Conclusions :
Our prototype miniature handheld OCT system incorporates protocols and algorithms that permit in vivo imaging of retina 3D structures and high resolution blood vessel maps in human subjects. We demonstrate the advantages of handheld OCT in rapid, non-invasive imaging and quantifications of retinal perfusion states. As OCT imaging technologies continue to advance, hand-held OCTA probe may become useful in pediatric ophthalmic diagnosis as well as prematurity screening.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.