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CHAMPAIGN
2151 South Neil Street • Champaign, IL 61820
217.352.2020

DANVILLE
2 E Main Street, Suite 116A • Danville, IL 61832
217.446.2020

Dr Sayegh is actively involved in research and he would like to share some of his research areas with you.

 

Femtosecond lasers:  The use of femtosecond lasers has proven to be a very powerful and versatile tool in the area of ophthalmic surgery.  LASIK has benefited from the creation of controlled flaps and all-laser procedures and cataract surgery is contemplating a move to a femtosecond laser platform in the coming years.  A Nobel Prize for femtosecond spectroscopy was awarded to Dr. Ahmed Zuwail of Caltech. Leading the effort of femtosecond ophthalmic applications starting in the mid and late 90s, Dr Sayegh pioneered a technology that has and will profoundly impact ophthalmic surgery.  His work was in collaboration with Dr. Ron Kurtz and other Intralase and Center for Ultrafast Optical Sciences members at the University of Michigan in Ann Arbor. http://www.engin.umich.edu/research/cuos/

 

Intraocular Lens Power Calculations for Cataract Surgery: The choice of the correct intraocular lens (IOL) is a critical step that completes the elegance and spectacular results offered by modern cataract surgery.  Decades went by when the precise understanding and calculation of such IOL powers eluded the scientific and medical community.  The advent of LASIK made the situation more complex and so called “refractive surprises”multiplied.  Several ad hoc solutions were proposed but they continued to be unreliable.   Dr. Sayegh pioneered a method that established the relationship between the theoretical optics based models and the regression methods used for decades, thus identifying the sources of errors and opening the door to better refractive results for patients undergoing cataract surgery many years following a LASIK procedure. Initial work was performed while Dr. Sayegh was at Washington University in Saint Louis and Barnes Hospital and refinement to the method is ongoing.   Dr. Sayegh received an American Society of Cataract and Refractive Surgery best paper award for this work.  (link:)

 

Optical Coherence Tomography(OCT):  A new imaging technique developed at MIT and patented in 1991, OCT has offered a fundamental addition to clinical tools by allowing a layer by layer visualization of delicate ocular tissue in both the front and back of the eye.  In addition to offering our patients on a daily basis the most sophisticated OCT tools, our clinic is also involved in several projects related to this novel technology. Novel techniques to extract clinically useful data are being developed.  In addition The EYE Center is part of a collaboratory involving the University of Illinois, Texas Instrument, Welch Allyn, Carle Clinic and others, in a 5 year NIH funded project that is implementing hand held devices and developing methods that will facilitate the early diagnosis of diabetic eye disease in addition to other conditions.  Dr. Sayegh is leading the clinical ophthalmic applications of the project and is working in close collaboration with Prof. Steve Boppart of the University of Illinois. http://biophotonics.illinois.edu/

 

Differential Geometry and Corneal Topography:  The topography of the cornea is of fundamental importance to the quality of vision and is the main target of LASIK and other refractive corneal surgeries.  The exact characterization of such a topography and methods to safely modify it are keys to the delivery of the highest acuity and quality of vision.  Methods of differential geometry and of laser physics are brought to bear on the means to achieve these goals.  This work is in collaboration with Prof.  Franco Nori of the University of Michigan and Prof. Delia Debuc from the Bascom Palmer Institute and former graduate student of Dr. Sayegh.  Representative work relating to this research was recently presented at the American Society of Cataract Surgery meeting in San Diego.

 

EYE Testing: Algorithms and Devices.  The determination of the visual acuity and the needed refractive correction (glasses, contacts, laser parameter for LASIK) for a patient is one of the most fundamental tasks performed at an eye clinic. Paper/plastic charts are often used and computer system are becoming more common.   We ask the fundamental question of whether traditional methods of presentation and determination of refractive state are optimal and design algorithms and devices to test the different hypotheses and define the future generation of methods.   Software developed and refined over the past 12 years is used at out clinic and is evolving into an automated, rapidly convergent algorithm of determining refractive error.  Collaboration with Illini Computing, a Champaign based software company is under study.

 

Matrix Methods in Mathematica for the design and choice of intraocular lenses.  An approach based on matrix methods in Mathematica, to allow for the analysis and computation of IOL powers.  While the basic matrix approach corresponds to paraxial optics, it can be extended to include astigmatism and other aberrations.    We apply our methods to compute lens powers including toric lenses that correct for both defocus (myopia, hyperopia) and astigmatism.  We show how the specific use of Mathematica allows an elegant and powerful method for the design and analysis of these intraocular lenses.  This work is in collaboration with David Hjelmstad of Arizona State University and Dr. Jean-Phillipe Collliac from Paris, France.  The Mathematica software is developed by Wolfram Inc. of Champaign, IL.

 

Profilometry and Subsurface Imaging in Point of Care Diagnostics in Ocular and Neoplastic Disease.

This project is concerned with applying techniques developed and evolving in the realm of ophthalmology to address important issues in breast cancer imaging and therapy.  It consists of

1) Use of topographical techniques analogous to those used in corneal topography

2)      Development of point-of-care lymphedema detection and characterization based on off-the-shelf hardware

3)      Defining and implementing the role of subsurface imaging

4)      Multimodal diagnostics and integration yielding higher sensitivity/ specificity

The project is in collaboration with Prof. Alphonse Taghian of the Massachusetts General Hospital and Harvard University.  A presentation of the main results is planned for the Photonics West Conference in San Francisco in February of 2013.