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Guan A, Richardson S, Hinckley S. Optical coherence tomography modeling incorporating scattering, absorption, and multiple reflections. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2020; 37:391-398. [PMID: 32118922 DOI: 10.1364/josaa.377121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
A direct scattering optical coherence tomography forward model was developed to simulate A-scans for both idealized and real light sources on an arbitrary given sample structure. Previous models neglected absorption, scattering, and multiple reflections at interfacial layers, and so two extended models were developed to investigate the impact of these processes. The first model uses the Beer-Lambert law to incorporate both absorption and scattering optical processes, and the second model uses a recursive form to model multiple reflections. These models were tested on a structure representative of a multilayered skin sample. The results show that the absorption and scattering processes have significant impact on the height of the peaks in the simulated A-scans. Conversely, the incorporation of multiple reflections has very little impact on the height of these peaks. Neither of the above processes has any impact on the locations of the A-scan peaks, which are associated with the sample interfaces between layers.
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Characterization of Corneal Donor Tissue Lesions by Anterior Segment Optical Coherence Tomography Compared With Eye Bank Technician Slit-Lamp Examination. Cornea 2018; 37:1318-1323. [PMID: 30044250 DOI: 10.1097/ico.0000000000001700] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
PURPOSE To compare anterior segment spectral-domain optical coherence tomography (OCT) with eye bank technician slit-lamp examination (SLE) in characterizing lesions in donor corneas. METHODS Twenty-nine donor corneas identified by eye bank technicians to have opacities or lesions potentially representing pathologic findings affecting the stroma were evaluated through the use of technician SLE, SLE photography, and OCT. Technicians were tasked with describing the lesion, estimating the lesion depth, and photographing their SLE findings. A masked grader evaluated the OCT images and measured the lesion depth using customized software. The lesions identified on OCT were then compared with those identified on SLE. RESULTS A total of 37 lesions were detected on SLE; 25 of the 37 lesions identified on SLE were matched to a lesion on OCT. SLE and OCT depth measurements were statistically significantly different (P = 0.0042, mean difference 4.8% ± 6.5%), and OCT graded lesions as slightly deeper. Of the 12 out of the 37 lesions that were noted on SLE (but not identified on OCT), these included 2 central and paracentral anterior stromal lesions (OCT showed loose epithelium), 5 peripheral anterior stromal lesions, and 5 corneas with LASIK. CONCLUSIONS Our study highlights both advantages and limitations of OCT compared with technician SLE in the evaluation of donor corneal tissue. Although OCT may miss some peripheral lesions and LASIK scars that are identifiable on SLE, OCT's depth resolution is helpful in differentiating whether shallow anterior opacities actually extend deeper into the stroma or are confined superficially to the epithelium.
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Borderie M, Grieve K, Irsch K, Ghoubay D, Georgeon C, De Sousa C, Laroche L, Borderie VM. New parameters in assessment of human donor corneal stroma. Acta Ophthalmol 2017; 95:e297-e306. [PMID: 28133954 DOI: 10.1111/aos.13351] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Accepted: 11/05/2016] [Indexed: 12/16/2022]
Abstract
PURPOSE To provide quantitative parameters for assessment of human donor corneal stroma by imaging stromal features of diseased and normal human corneas with full-field optical coherence microscopy (FFOCM), using confocal microscopy (CM) and histology as reference techniques. METHODS Bowman's layer (BL) thickness and keratocyte density were assessed ex vivo in 23 human donor corneas and 27 human pathological corneas (keratoconus and other corneal disorders) with FFOCM, CM and histology. Stromal backscattering was assessed with FFOCM. Additionally, 10 normal human corneas were assessed in vivo with CM. RESULTS In FFOCM, the logarithm of the normalized stromal reflectivity was a linear function of stromal depth (R2 = 0.95) in human donor corneas. Compared with keratoconus corneas, human donor corneas featured higher BL thickness (p = 0.0014) with lower coefficient of variation (BL-COV; p = 0.0002), and linear logarithmic stromal reflectivity with depth (higher R2 , p = 0.0001). Compared with other corneal disorders, human donor corneas featured lower BL-COV (p = 0.012) and higher R2 (p = 0.0001). Using the 95% confidence limits of the human donor cornea group, BL thickness < 6.5 μm (sensitivity, 57%; specificity, 100%), BL-COV > 18.6% (79%; 100%) and R2 < 0.94 (93%; 71%) were revealed as indictors of abnormal cornea. In CM, keratocyte density decreased with stromal depth (r = -0.56). The mean overall keratocyte density (cells/mm2 ) was 205 in human donor corneas, 244 in keratoconus, 176 in other corneal disorders and 386 in normal corneas. CONCLUSION Full-field optical coherence microscopy (FFOCM) provides precise and reliable parameters for non-invasive assessment of human donor corneal stroma during storage, enabling detection of stromal disorders that could impair the results of keratoplasty.
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Affiliation(s)
- Marie Borderie
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
| | - Kate Grieve
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
| | - Kristina Irsch
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
- Laboratory of Ophthalmic Instrument Development; The Wilmer Eye Institute; The Johns Hopkins University School of Medicine; Baltimore Maryland USA
| | - Djida Ghoubay
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
| | - Cristina Georgeon
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
| | - Celine De Sousa
- Tissue Bank; French Blood Establishment; Paris Ile-de-France France
| | - Laurent Laroche
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
| | - Vincent M. Borderie
- Quinze-Vingts National Ophthalmology Hospital; Paris VI University; Paris France
- Vision Institute/CIC 1423; UMR_S 968/INSERM, U968/CHNO/CNRS, UMR_7210; UPMC University Paris 06; Paris France
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Mortensen LJ, Alt C, Turcotte R, Masek M, Liu TM, Côté DC, Xu C, Intini G, Lin CP. Femtosecond laser bone ablation with a high repetition rate fiber laser source. BIOMEDICAL OPTICS EXPRESS 2015; 6:32-42. [PMID: 25657872 PMCID: PMC4317121 DOI: 10.1364/boe.6.000032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/29/2014] [Accepted: 09/30/2014] [Indexed: 05/20/2023]
Abstract
Femtosecond laser pulses can be used to perform very precise cutting of material, including biological samples from subcellular organelles to large areas of bone, through plasma-mediated ablation. The use of a kilohertz regenerative amplifier is usually needed to obtain the pulse energy required for ablation. This work investigates a 5 megahertz compact fiber laser for near-video rate imaging and ablation in bone. After optimization of ablation efficiency and reduction in autofluorescence, the system is demonstrated for the in vivo study of bone regeneration. Image-guided creation of a bone defect and longitudinal evaluation of cellular injury response in the defect provides insight into the bone regeneration process.
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Affiliation(s)
- Luke J. Mortensen
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts,
USA
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
| | - Clemens Alt
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
| | - Raphaël Turcotte
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts,
USA
| | - Marissa Masek
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
| | - Tzu-Ming Liu
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
- Institute of Biomedical Engineering, National Taiwan University, Taipei,
Taiwan
| | - Daniel C. Côté
- Centre de Recherche Université Laval Robert-Giffard, Université Laval, Québec, QC G1J2G3,
Canada
| | - Chris Xu
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York,
USA
| | - Giuseppe Intini
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts,
USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts,
USA
- Co-corresponding authors
| | - Charles P. Lin
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,
USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts,
USA
- Co-corresponding authors
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Ghouali W, Grieve K, Bellefqih S, Sandali O, Harms F, Laroche L, Paques M, Borderie V. Full-Field Optical Coherence Tomography of Human Donor and Pathological Corneas. Curr Eye Res 2014; 40:526-34. [DOI: 10.3109/02713683.2014.935444] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Latour G, Kowalczuk L, Savoldelli M, Bourges JL, Plamann K, Behar-Cohen F, Schanne-Klein MC. Hyperglycemia-induced abnormalities in rat and human corneas: the potential of second harmonic generation microscopy. PLoS One 2012; 7:e48388. [PMID: 23139780 PMCID: PMC3489670 DOI: 10.1371/journal.pone.0048388] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 09/24/2012] [Indexed: 11/28/2022] Open
Abstract
Background Second Harmonic Generation (SHG) microscopy recently appeared as an efficient optical imaging technique to probe unstained collagen-rich tissues like cornea. Moreover, corneal remodeling occurs in many diseases and precise characterization requires overcoming the limitations of conventional techniques. In this work, we focus on diabetes, which affects hundreds of million people worldwide and most often leads to diabetic retinopathy, with no early diagnostic tool. This study then aims to establish the potential of SHG microscopy for in situ detection and characterization of hyperglycemia-induced abnormalities in the Descemet’s membrane, in the posterior cornea. Methodology/Principal Findings We studied corneas from age-matched control and Goto-Kakizaki rats, a spontaneous model of type 2 diabetes, and corneas from human donors with type 2 diabetes and without any diabetes. SHG imaging was compared to confocal microscopy, to histology characterization using conventional staining and transmitted light microscopy and to transmission electron microscopy. SHG imaging revealed collagen deposits in the Descemet’s membrane of unstained corneas in a unique way compared to these gold standard techniques in ophthalmology. It provided background-free images of the three-dimensional interwoven distribution of the collagen deposits, with improved contrast compared to confocal microscopy. It also provided structural capability in intact corneas because of its high specificity to fibrillar collagen, with substantially larger field of view than transmission electron microscopy. Moreover, in vivo SHG imaging was demonstrated in Goto-Kakizaki rats. Conclusions/Significance Our study shows unambiguously the high potential of SHG microscopy for three-dimensional characterization of structural abnormalities in unstained corneas. Furthermore, our demonstration of in vivo SHG imaging opens the way to long-term dynamical studies. This method should be easily generalized to other structural remodeling of the cornea and SHG microscopy should prove to be invaluable for in vivo corneal pathological studies.
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Affiliation(s)
- Gaël Latour
- Laboratory for Optics and Biosciences, École Polytechnique, CNRS, INSERM U696, Palaiseau, France
| | - Laura Kowalczuk
- Laboratory of Applied Optics, ENSTA ParisTech, École Polytechnique, CNRS, Palaiseau, France
- Team17: Physiopathology of Ocular Diseases, Therapeutic Innovations, INSERM UMRS 872, Paris, France
- Centre de Recherche des Cordeliers, Pierre et Marie Curie University, Paris, France
- Department of Ophthalmology, AP-HP Hôtel-Dieu, Paris Descartes University, Faculty of Medicine, Sorbonne Paris Cité, Paris, France
| | - Michèle Savoldelli
- Department of Ophthalmology, AP-HP Hôtel-Dieu, Paris Descartes University, Faculty of Medicine, Sorbonne Paris Cité, Paris, France
| | - Jean-Louis Bourges
- Department of Ophthalmology, AP-HP Hôtel-Dieu, Paris Descartes University, Faculty of Medicine, Sorbonne Paris Cité, Paris, France
| | - Karsten Plamann
- Laboratory of Applied Optics, ENSTA ParisTech, École Polytechnique, CNRS, Palaiseau, France
| | - Francine Behar-Cohen
- Team17: Physiopathology of Ocular Diseases, Therapeutic Innovations, INSERM UMRS 872, Paris, France
- Centre de Recherche des Cordeliers, Pierre et Marie Curie University, Paris, France
- Department of Ophthalmology, AP-HP Hôtel-Dieu, Paris Descartes University, Faculty of Medicine, Sorbonne Paris Cité, Paris, France
| | - Marie-Claire Schanne-Klein
- Laboratory for Optics and Biosciences, École Polytechnique, CNRS, INSERM U696, Palaiseau, France
- * E-mail:
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Jung Y, Nichols AJ, Klein OJ, Roussakis E, Evans CL. Label-Free, Longitudinal Visualization of PDT Response In Vitro with Optical Coherence Tomography. Isr J Chem 2012; 52:728-744. [PMID: 23316088 PMCID: PMC3538822 DOI: 10.1002/ijch.201200009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A major challenge in creating and optimizing therapeutics in the fight against cancer is visualizing and understanding the microscale spatiotemporal treatment response dynamics that occur in patients. This is especially true for photodynamic therapy (PDT), where therapeutic optimization relies on understanding the interplay between factors such as photosensitizer localization and uptake, in addition to light dose and delivery rate. In vitro 3D culture systems that recapitulate many of the biological features of human disease are powerful platforms for carrying out detailed studies on PDT response and resistance. Current techniques for visualizing these models, however, often lack accuracy due to the perturbative nature of the sample preparation, with light attenuation complicating the study of intact models. Optical coherence tomography (OCT) is an ideal method for the long-term, non-perturbative study of in vitro models and their response to PDT. Monitoring the response of 3D models to PDT by time-lapse OCT methods promises to provide new perspectives and open the way to cancer treatment methodologies that can be translated towards the clinic.
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Affiliation(s)
- Yookyung Jung
- Wellman Center for Photomedicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (USA)
| | - Alexander J. Nichols
- Wellman Center for Photomedicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (USA)
- Harvard University, Program in Biophysics, Cambridge, Massachusetts (USA)
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts (USA)
| | - Oliver J. Klein
- Wellman Center for Photomedicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (USA)
| | - Emmanuel Roussakis
- Wellman Center for Photomedicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (USA)
| | - Conor L. Evans
- Wellman Center for Photomedicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (USA)
- Harvard University, Program in Biophysics, Cambridge, Massachusetts (USA)
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Casadessus O, Georges G, Lamoine LS, Deumié C, Hoffart L. Light scattering from edematous human corneal grafts' microstructure: experimental study and electromagnetic modelization. BIOMEDICAL OPTICS EXPRESS 2012; 3:1793-1810. [PMID: 22876345 PMCID: PMC3409700 DOI: 10.1364/boe.3.001793] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 03/31/2012] [Accepted: 04/29/2012] [Indexed: 06/01/2023]
Abstract
Along with the lens, the cornea is the only transparent tissue in the human body. However, the development of an edema involves structural disturbances increasing light scattering and leading to the opacification of the cornea. Several mechanisms of transparency loss have been studied in the literature, but the whole phenomenon is complex and the part played by each scatterer is still unclear. We propose here to study human corneal grafts combining microscopic OCT imagery with far-field measurement of the scattered light in the reflected half-space. We introduce afterwards numerical calculations based on electromagnetic equations solved with first order approximation to link the observed microscopic-scale structural modifications with the intensity level of the scattered light, and to try and quantify the relationship between them.
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Affiliation(s)
- Olivier Casadessus
- Institut Fresnel, UMR CNRS 7249, Université d’Aix-Marseille, Ecole Centrale Marseille, Domaine universitaire de Saint Jérôme, Avenue Escadrille Normandie Niemen, 13 397 Marseille cedex 20, France
| | - Gaëlle Georges
- Institut Fresnel, UMR CNRS 7249, Université d’Aix-Marseille, Ecole Centrale Marseille, Domaine universitaire de Saint Jérôme, Avenue Escadrille Normandie Niemen, 13 397 Marseille cedex 20, France
| | - Laure Siozade Lamoine
- Institut Fresnel, UMR CNRS 7249, Université d’Aix-Marseille, Ecole Centrale Marseille, Domaine universitaire de Saint Jérôme, Avenue Escadrille Normandie Niemen, 13 397 Marseille cedex 20, France
| | - Carole Deumié
- Institut Fresnel, UMR CNRS 7249, Université d’Aix-Marseille, Ecole Centrale Marseille, Domaine universitaire de Saint Jérôme, Avenue Escadrille Normandie Niemen, 13 397 Marseille cedex 20, France
| | - Louis Hoffart
- Service d’Ophtalmologie de l’Hôpital de la Timone, APHM, Université d’Aix-Marseille, 264 rue Saint Pierre, 13 385 Marseille Cedex 5, France
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Latour G, Gusachenko I, Kowalczuk L, Lamarre I, Schanne-Klein M. In vivo structural imaging of the cornea by polarization-resolved second harmonic microscopy. BIOMEDICAL OPTICS EXPRESS 2012; 3:1-15. [PMID: 22254163 PMCID: PMC3255328 DOI: 10.1364/boe.3.000001] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 11/29/2011] [Accepted: 11/29/2011] [Indexed: 05/18/2023]
Abstract
The transparency and mechanical strength of the cornea are related to the highly organized three-dimensional distribution of collagen fibrils. It is of great interest to develop specific and contrasted in vivo imaging tools to probe these collagenous structures, which is not available yet. Second Harmonic Generation (SHG) microscopy is a unique tool to reveal fibrillar collagen within unstained tissues, but backward SHG images of cornea fail to reveal any spatial features due to the nanometric diameter of stromal collagen fibrils. To overcome this limitation, we performed polarization-resolved SHG imaging, which is highly sensitive to the sub-micrometer distribution of anisotropic structures. Using advanced data processing, we successfully retrieved the orientation of the collagenous fibrils at each depth of human corneas, even in backward SHG homogenous images. Quantitative information was also obtained about the submicrometer heterogeneities of the fibrillar collagen distribution by measuring the SHG anisotropy. All these results were consistent with numerical simulation of the polarization-resolved SHG response of cornea. Finally, we performed in vivo SHG imaging of rat corneas and achieved structural imaging of corneal stroma without any labeling. Epi-detected polarization-resolved SHG imaging should extend to other organs and become a new diagnosis tool for collagen remodeling.
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Affiliation(s)
- Gaël Latour
- Laboratory for Optics and Biosciences, École Polytechnique—CNRS—INSERM, 91128 Palaiseau, France
| | - Ivan Gusachenko
- Laboratory for Optics and Biosciences, École Polytechnique—CNRS—INSERM, 91128 Palaiseau, France
| | - Laura Kowalczuk
- Laboratory for Applied Optics, ENSTA ParisTech—École Polytechnique—CNRS, 91761 Palaiseau, France
| | - Isabelle Lamarre
- Laboratory for Optics and Biosciences, École Polytechnique—CNRS—INSERM, 91128 Palaiseau, France
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Verrier I, Veillas C, Lépine T, Nguyen F, Thuret G, Gain P. Interfaces detection after corneal refractive surgery by low coherence optical interferometry. BIOMEDICAL OPTICS EXPRESS 2010; 1:1460-1471. [PMID: 21258562 PMCID: PMC3018127 DOI: 10.1364/boe.1.001460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/10/2010] [Accepted: 11/12/2010] [Indexed: 05/30/2023]
Abstract
The detection of refractive corneal surgery by LASIK, during the storage of corneas in Eye Banks will become a challenge when the numerous operated patients will arrive at the age of cornea donation. The subtle changes of corneal structure and refraction are highly suspected to negatively influence clinical results in recipients of such corneas. In order to detect LASIK cornea interfaces we developed a low coherence interferometry technique using a broadband continuum source. Real time signal recording, without moving any optical elements and without need of a Fourier Transform operation, combined with good measurement resolution is the main asset of this interferometer. The associated numerical processing is based on a method initially used in astronomy and offers an optimal correlation signal without the necessity to image the whole cornea that is time consuming. The detection of corneal interfaces - both outer and inner surface and the buried interface corresponding to the surgical wound - is then achieved directly by the innovative combination of interferometry and this original numerical process.
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Affiliation(s)
- I. Verrier
- Université de Lyon, F-42023, Saint-Etienne, France
- CNRS, UMR 5516, Laboratoire Hubert Curien, F-42000 Saint-Etienne, France
| | - C. Veillas
- Université de Lyon, F-42023, Saint-Etienne, France
- CNRS, UMR 5516, Laboratoire Hubert Curien, F-42000 Saint-Etienne, France
| | - T. Lépine
- Université de Lyon, F-42023, Saint-Etienne, France
- CNRS, UMR 5516, Laboratoire Hubert Curien, F-42000 Saint-Etienne, France
- Institut d’Optique Rhône-Alpes, 18, rue Benoît LAURAS 42000 Saint-Etienne, France
| | - F. Nguyen
- Université de Lyon, F-42023, Saint-Etienne, France
- Laboratoire Biologie, Ingénerie et Imagerie de la Greffe de Cornée, JE2521, IFR143,
Université Saint-Etienne, Jean Monnet, F-42000, Saint-Etienne, France
| | - G. Thuret
- Université de Lyon, F-42023, Saint-Etienne, France
- Laboratoire Biologie, Ingénerie et Imagerie de la Greffe de Cornée, JE2521, IFR143,
Université Saint-Etienne, Jean Monnet, F-42000, Saint-Etienne, France
| | - P. Gain
- Université de Lyon, F-42023, Saint-Etienne, France
- Laboratoire Biologie, Ingénerie et Imagerie de la Greffe de Cornée, JE2521, IFR143,
Université Saint-Etienne, Jean Monnet, F-42000, Saint-Etienne, France
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