Accurate quantitative imaging of the cornea is critical for predictable outcomes in corneal based surgical interventions. While long the standard, reflection based corneal topography to assess corneal curvature and refractive power is insufficient in an era when surgical manipulation of the corneal shape is routine and undermines the basis of reflection topography. Laser refractive surgery is one particular corneal intervention that has revealed current inadequacies in measuring the cornea. Over 7 million people in the United States have had some form of laser refractive surgery to reduce their dependence on corrective eye wear. The corneal reshaping that occurs from laser refractive surgery results in excellent visual results for the patient but renders current technologies incapable of accurately measuring the power of the reshaped cornea. Accurate measurement of corneal power is critical in applications such as the prediction of intraocular lens power needed after cataract surgery, an event which this group of patients will invariably encounter as they age into late adulthood. Our proposed development of a motion corrected high-speed spectral domain optical coherence tomography (SDOCT) based device which can directly map corneal surfaces at micron resolution and then accurately convert this data to keratometric values will greatly aid clinical applications dependent on this value. The primary innovations will be the development of novel hardware and software methods to account for involuntary patient motion and for refraction of OCT light within the cornea. A clinical comparison will then be made in patients undergoing laser refractive surgery to compare the measurements made by SDOCT versus existing clinical instrumentation for the measurement of corneal power.

Public Health Relevance

We propose to develop an improved ocular anterior segment imaging system using spectral domain optical coherence tomography. If successful, this project could support widespread adoption of SDOCT as the preferred, single-platform anterior segment imaging device in eye care delivery.

National Institute of Health (NIH)
National Eye Institute (NEI)
Exploratory/Developmental Grants (R21)
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Special Emphasis Panel (ZRG1-ETTN-E (92))
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Wujek, Jerome R
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Duke University
Biomedical Engineering
Schools of Engineering
United States
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McNabb, Ryan P; Farsiu, Sina; Stinnett, Sandra S et al. (2015) Optical coherence tomography accurately measures corneal power change from laser refractive surgery. Ophthalmology 122:677-86
Kuo, Anthony N; McNabb, Ryan P; Chiu, Stephanie J et al. (2013) Correction of ocular shape in retinal optical coherence tomography and effect on current clinical measures. Am J Ophthalmol 156:304-11
McNabb, Ryan P; Kuo, Anthony N; Izatt, Joseph A (2013) Quantitative single and multi-surface clinical corneal topography utilizing optical coherence tomography. Opt Lett 38:1212-4
McNabb, Ryan P; Larocca, Francesco; Farsiu, Sina et al. (2012) Distributed scanning volumetric SDOCT for motion corrected corneal biometry. Biomed Opt Express 3:2050-65
Kuo, Anthony N; McNabb, Ryan P; Zhao, Mingtao et al. (2012) Corneal biometry from volumetric SDOCT and comparison with existing clinical modalities. Biomed Opt Express 3:1279-90