Abstract
Purpose :
The aqueous inflow and outflow systems are crucial in maintaining intraocular pressure (IOP) balance, a key risk factor in glaucoma development and progression. Swept-Source optical coherence tomography (SS-OCT) can be used to image the individual anatomical components of the outflow system, which may be useful in glaucoma research as well as pre and post-surgical assessment of minimally invasive glaucoma surgeries (MIGS). We conducted a clinical study to evaluate the ability of a SS-OCT device to acquire High Definition images of these structures
Methods :
A modified PLEX® Elite 9000 (ZEISS, Dublin, CA) SS-OCT system operating at 1060 nm was used to image the anterior segment of 5 healthy volunteers and one glaucoma subject. The limbal area of every subject was imaged using a 3x3mm scan pattern which captures 300 A-scans/B-scan, repeated, registered and averaged 20 times, and a total of 51 B-scans. A single-line scan containing 1024 A-scans was also used to image the ocular lens
Results :
A total of 10 eyes of 6 subjects were imaged in this study. Figure 1A and 1B show the ciliary body of two subjects with their eyes aligned to allow light penetration through the scleral tissue. The deep penetration of the SS-OCT wavelength together with image averaging allows for visualization of the deeper structures. Figures 1C illustrates the location of Schlemm’s canal, while 1D shows a collector channel branching out to an episcleral vein. Lastly, image 1E was acquired from a fully dilated patient. The 16mm long frame shows most of the lens capsule and its nucleus. The reduction in noise due to registration and averaging allows the user to discern the tissue layers
Conclusions :
We have demonstrated the ability of an SS-OCT system to obtain high definition structural images of the anterior segment structures and the aqueous outflow system. Being able to clearly asses such a tissue noninvasively could be a powerful tool to evaluate and track glaucoma surgery recipients as well as patients with uveitis and ciliary tumors
This abstract was presented at the 2019 ARVO Imaging in the Eye Conference, held in Vancouver, Canada, April 26-27, 2019.