Purpose: To test the feasibility of measuring the entire thickness profiles of the epithelium and contact lens (CL) in vivo, using high-speed and high-resolution spectral-domain optical coherence tomography (SD-OCT).
Methods: A custom-built, long scan depth SD-OCT was developed based on a complementary metal oxide semiconductor (CMOS) camera, and the axial resolution was approximately 5.1 μm in tissue. Five eyes of five subjects were imaged twice across the horizontal meridian before and while wearing one CL. Semiautomatic measurement was done to yield the entire thickness profiles of the epithelium, total cornea, and CL after correcting for optical distortion.
Results: The full width and depth of the epithelium, ocular surface, and CL were clearly visualized. The epithelial thickness at the center was 51.9±3.5 μm; it remained at this thickness across the central 7 mm diameter and then increased at both temporal and nasal peripheries. The CL profile showed the thinnest point at the center with thickness of 100.3±4.9 μm. The thickness increased toward the midperiphery and then decreased at the edge.
Conclusions: This pilot study demonstrated the feasibility of using high-speed CMOS-based OCT to evaluate the entire thickness profiles of the epithelium and CL in vivo. Further development will be needed to extend the scanning from 2D to 3D with a robust automatic image processing ability.
Bascom Palmer Eye Institute (A.T., Y.S., H.J., Y.Y., J.W.), University of Miami, Miami, FL;
School of Ophthalmology and Optometry (A.T., Y.S., F.L., M.S., D.Z.), Wenzhou Medical College, Wenzhou, Zhejiang, China;
Department of Electrical and Computer Engineering (J.W.), University of Miami, Miami, FL; and
Hangzhou First People's Hospital (Y.Y.), Hangzhou, Zhejiang, China.
Address correspondence to Jianhua Wang, M.D., Ph.D., Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, 1638 NW 10th Avenue, McKnight Building—Room 202A, Miami, FL 33136; e-mail: firstname.lastname@example.org
Supported by the NIH Grant 1R21EY021336, NIH Center Core Grant P30EY014801, Research to Prevent Blindness Unrestricted Grant, Department of Defense (DOD- Grant W81XWH-09-1-0675), and the Visiting scholar activity (Y.L.S.) was supported by research grants from the Affiliated Eye Hospital of Wenzhou Medical College (YNZD201004).
Contributions of the authors: Design of the study (A.T., J.W., Y.S.); conduct of the study, data collection, analysis, and interpretation (A.T., Y.S., H.J., J.W., Y.Y., F.L., M.S., D.Z.).
The authors have no proprietary interest in any materials or methods described within this article.
The research review board of University of Miami approved this study.
Accepted June 09, 2013