Optical Assessment of Soft Contact Lens Edge-Thickness

Purpose To assess the edge shape of soft contact lenses using Gabor-Domain Optical Coherence Microscopy (GD-OCM) with a 2-&mgr;m imaging resolution in three dimensions and to generate edge-thickness profiles at different distances from the edge tip of soft contact lenses. Methods A high-speed custom-designed GD-OCM system was used to produce 3D images of the edge of an experimental soft contact lens (Bausch + Lomb, Rochester, NY) in four different configurations: in air, submerged into water, submerged into saline with contrast agent, and placed onto the cornea of a porcine eyeball. An algorithm to compute the edge-thickness was developed and applied to cross-sectional images. The proposed algorithm includes the accurate detection of the interfaces between the lens and the environment, and the correction of the refraction error. Results The sharply defined edge tip of a soft contact lens was visualized in 3D. Results showed precise thickness measurement of the contact lens edge profile. Fifty cross-sectional image frames for each configuration were used to test the robustness of the algorithm in evaluating the edge-thickness at any distance from the edge tip. The precision of the measurements was less than 0.2 &mgr;m. Conclusions The results confirmed the ability of GD-OCM to provide high-definition images of soft contact lens edges. As a nondestructive, precise, and fast metrology tool for soft contact lens measurement, the integration of GD-OCM in the design and manufacturing of contact lenses will be beneficial for further improvement in edge design and quality control. In the clinical perspective, the in vivo evaluation of the lens fitted onto the cornea will advance our understanding of how the edge interacts with the ocular surface. The latter will provide insights into the impact of long-term use of contact lenses on the visual performance.

[1]  Eric Clarkson,et al.  Measurement of a multi-layered tear film phantom using optical coherence tomography and statistical decision theory. , 2014, Biomedical optics express.

[2]  P. McMenamin,et al.  Normal anatomy of the aqueous humour outflow system in the domestic pig eye. , 1991, Journal of anatomy.

[3]  Panomsak Meemon,et al.  Assessment of a liquid lens enabled in vivo optical coherence microscope. , 2010, Applied optics.

[4]  Meixiao Shen,et al.  Characterization of soft contact lens edge fitting using ultra-high resolution and ultra-long scan depth optical coherence tomography. , 2011, Investigative ophthalmology & visual science.

[5]  L Keay,et al.  Tear exchange under hydrogel contact lenses: methodological considerations. , 2001, Investigative ophthalmology & visual science.

[6]  Thierry Lepine,et al.  Influence of interfaces reflectivity for central thickness measurement of a contact lens by low coherence interferometry , 2013 .

[7]  A. Fercher,et al.  Optical coherence tomography - principles and applications , 2003 .

[8]  P. Meemon,et al.  Gabor domain optical coherence microscopy , 2008, BiOS.

[9]  Panomsak Meemon,et al.  Gabor-based fusion technique for Optical Coherence Microscopy. , 2010, Optics express.

[10]  Kevin P Thompson,et al.  Broadband astigmatism-corrected Czerny-Turner spectrometer. , 2010, Optics express.

[11]  Meixiao Shen,et al.  Entire Contact Lens Imaged In Vivo and In Vitro With Spectral Domain Optical Coherence Tomography , 2010, Eye & contact lens.

[12]  J. Fujimoto,et al.  Optical coherence tomography: an emerging technology for biomedical imaging and optical biopsy. , 2000, Neoplasia.

[13]  J. Jackson,et al.  Vision Specific Quality of Life of Pediatric Contact Lens Wearers , 2010, Optometry and vision science : official publication of the American Academy of Optometry.

[14]  Angelika Unterhuber,et al.  In vivo tear film thickness measurement and tear film dynamics visualization using spectral domain optical coherence tomography. , 2015, Optics express.

[15]  Daniel F Kiernan,et al.  Spectral-domain optical coherence tomography: a comparison of modern high-resolution retinal imaging systems. , 2010, American journal of ophthalmology.

[16]  Patrice Tankam,et al.  Assessing microstructures of the cornea with Gabor-domain optical coherence microscopy: pathway for corneal physiology and diseases. , 2015, Optics letters.

[17]  Shuo Tang,et al.  Cornea characterization using a combined multiphoton microscopy and optical coherence tomography system. , 2014, Biomedical optics express.

[18]  M. Wojtkowski,et al.  Corneal topography with high-speed swept source OCT in clinical examination , 2011, Biomedical optics express.

[19]  C. Leung,et al.  Retinal Nerve Fiber Layer Imaging with Spectral-domain Optical Coherence Tomography (OCT)—A Review of the Cirrus HD-OCT , 2011 .

[20]  D. Fonn,et al.  Targeting Contact Lens Induced Dryness and Discomfort: What Properties Will Make Lenses More Comfortable , 2007, Optometry and vision science : official publication of the American Academy of Optometry.

[21]  M. Doğru,et al.  The TFOS International Workshop on Contact Lens Discomfort: executive summary. , 2013, Investigative ophthalmology & visual science.

[22]  Patrenahalli M. Narendra,et al.  A Separable Median Filter for Image Noise Smoothing , 1981, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[23]  Jianhua Wang,et al.  Entire Thickness Profiles of the Epithelium and Contact Lens In Vivo Imaged With High-Speed and High-Resolution Optical Coherence Tomography , 2013, Eye & contact lens.

[24]  Jennifer K Barton,et al.  Application of optical coherence tomography to automated contact lens metrology. , 2010, Journal of biomedical optics.

[25]  Susana Marcos,et al.  Three-dimensional reconstruction of the crystalline lens gradient index distribution from OCT imaging. , 2010, Optics express.

[26]  Nathan Efron,et al.  The TFOS International Workshop on Contact Lens Discomfort: report of the contact lens interactions with the ocular surface and adnexa subcommittee. , 2013, Investigative ophthalmology & visual science.

[27]  Jannick P. Rolland,et al.  Optical Coherence Tomography Enabling Non Destructive Metrology of Layered Polymeric GRIN Material , 2013, Scientific Reports.

[28]  Jianhua Wang,et al.  The TFOS International Workshop on Contact Lens Discomfort: report of the contact lens interactions with the tear film subcommittee. , 2013, Investigative ophthalmology & visual science.

[29]  J. Izatt,et al.  3D refraction correction and extraction of clinical parameters from spectral domain optical coherence tomography of the cornea. , 2010, Optics express.

[30]  Kye-Sung Lee,et al.  Parallelized multi–graphics processing unit framework for high-speed Gabor-domain optical coherence microscopy , 2014, Journal of biomedical optics.

[31]  Sarfaraz Baig,et al.  Integrated optical coherence tomography and reflectometry system for ocular anterior segment imaging and tear film thickness evaluation , 2014 .

[32]  Supraja Murali,et al.  Three-dimensional adaptive microscopy using embedded liquid lens. , 2009, Optics letters.

[33]  James S. Wolffsohn,et al.  Impact of soft contact lens edge design and midperipheral lens shape on the epithelium and its indentation with lens mobility. , 2013, Investigative ophthalmology & visual science.

[34]  Dalip Singh Mehta,et al.  Tomographic and volumetric reconstruction of composite materials using full-field swept-source optical coherence tomography , 2012 .

[35]  J. Beauchamp,et al.  International Organization for Standardization (ISO) , 2015 .

[36]  J. Ruiz-Ederra,et al.  Comparative study of the three neurofilament subunits within pig and human retinal ganglion cells. , 2004, Molecular vision.

[37]  Eleonora Vaccari,et al.  Computerized analysis of the effects of intraocular lens edge design on the quality of vision in pseudophakic patients , 2003, Journal of cataract and refractive surgery.

[38]  Eric Clarkson,et al.  Dispersion control with a Fourier-domain optical delay line in a fiber-optic imaging interferometer. , 2005, Applied optics.