DYNAMIC FOCUSING SPIRAL SCAN OCT FOR HIGH RESOLUTION, WIDE FIELD CORNEAL AND ANTERIOR CHAMBER IMAGING

There is a need for high resolution, wide field corneal and anterior chamber volumetric images that enable clear visualization of surgical instruments and manipulation of tissue. Current optical coherence tomography (OCT) imaging of the ocular anterior segment typically requires tradeoffs between resolution and depth-of-focus due to corneal curvature and the deep anterior chamber. I have built a dynamically focusing OCT system coupled with constant linear velocity (CLV) spiral scanning that maintains focus from the corneal apex to the anterior lens during a scan. This eliminates acquisition dead times and achieves more uniform transverse sampling compared to raster scanning.

My work builds off of constant linear velocity spiral scanning OCT previously developed by Oscar M. Carrasco-Zevallos and linear dynamic focusing previously developed by Ryan McNabb. I adjust the imaging plane to dynamically focus along the spherical contour of a human cornea. Radial parameters can be adjusted based on measurements of the individual cornea. While imaging a subject at a fixed focus during volume acquisition provides high contrast at the corneal apex, it generates low contrast at the lens, iris, and periphery. In comparison, imaging a subject with spherical dynamic focusing CLV spiral scan generates a well-resolved image of the entire cornea, anterior lens, and iris processes. Thus, we have developed a high-speed OCT system to image the entire anterior chamber with high resolution and contrast over a large field of view in depth and transverse dimensions. This technology has the potential to reduce patient imaging time in clinical ophthalmology and yield high quality volumetric renders that enable clear visualization of ocular dynamics and surgical maneuvers.

Details

Project duration: Jan. 10, 2018 – Present

Weekly hours: 15

Total hours expected: 250

Supervisors: Dr. Anthony Kuo (anthony.kuo@duke.edu)