Purpose: : To demonstrate the depth resolved birefringence imaging of retina using polarization sensitive Fourier domain optical coherence tomography system. Methods: : Fiber-based polarization sensitive Fourier domain optical coherence tomography system was developed. Fiber birefringence was compensated with surface reflection from the retina. Phase retardation and orientation of the birefringence can be measured with Jones matrix based algorism in addition to conventional cross sectional OCT. Synchronized two line-CCD cameras allow high-speed measurement of birefringence of retina in vivo. Results: : Retinal phase retardation map was visualized as depth-resolved image. Retinal birefringence tomograph of healthy volunteers were analyzed and compared to earlier literatures; the results of polarization sensitive time domain optical coherence tomography and histological knowledge. Conclusions: : Polarization sensitive Fourier domain optical coherence tomography allowed visualizing depth-resolved ...

1. D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, Optical coherence tomography, Science 254, 1178-1181 (1991). [CrossRef] [PubMed] 2. G. J. Tearney, M. E. Brezinski, B. E. Bouma, S. A. Boppart, C. Pitris, J. F. Southern, and J. G. Fujimoto, In vivo endoscopic optical biopsy with optical coherence tomography, Science 276, 2037-2039 (1997). [CrossRef] [PubMed] 3. S. A. Boppart, B. E. Bouma, C. Pitris, J. F. Southern, M. E. Brezinski, and J. G. Fujimoto, In vivo cellular optical coherence tomography imaging, Nature Med. 4, 861-865 (1998). [CrossRef] [PubMed] 4. B. Bouma, G. J. Tearney, S. A. Boppart, M. R. Hee, M. E. Brezinski, and J. G. Fujimoto, High-resolution optical coherence tomographic imaging using a mode-locked Ti:Al2O3 laser source, Opt. Lett. 20, 1486-1488 (1995). [CrossRef] [PubMed] 5. B. E. Bouma, G. J. Tearney, I. P. Bilinsky, and B. Golubovic, Self phase modulated Kerr-lens ...

TY - JOUR. T1 - Age and retinal nerve fiber layer thickness measured by spectral domain optical coherence tomography.. AU - Lee, Jong Yeon. AU - Hwang, Young Hoon. AU - Lee, Sun Min. AU - Kim, Yong Yeon. PY - 2012/6/1. Y1 - 2012/6/1. N2 - To evaluate the association between age and peripapillary retinal nerve fiber layer (RNFL) thickness measured by Cirrus high-definition (HD) spectral domain optical coherence tomography (OCT) in healthy Korean subjects. A total of 302 eyes from 155 healthy Korean subjects (age range, 20 to 79 years) underwent RNFL thickness measurements using the Cirrus HD-OCT. Average, quadrant, and clock-hour RNFL thickness parameters were analyzed in terms of age using linear mixed effect models. Average RNFL demonstrated a slope of -2.1 μm per decade of age (p , 0.001). In quadrant analysis, superior (-3.4 μm/decade, p , 0.001) and inferior (-2.9 μm/decade, p , 0.001) quadrants showed steeper slopes, whereas temporal (-1.1 μm/decade, p , 0.001) and nasal (-1.0 ...

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Previous studies have almost exclusively used standard time-domain optical coherence tomography (TD-OCT, Stratus OCT; Carl Zeiss Meditec, Dublin, California) as a non-invasive retinal ocular imaging technique to measure structural changes in the axonal integrity of the retinal nerve fibre layer (RNFL) in patients with glaucoma, various optic neuropathies, optic neuritis (ON) and/or multiple sclerosis (MS).1-3 … ...

We demonstrate a novel technique to determine the size of Mie scatterers with high sensitivity. Our technique is based on spectral domain optical coherence tomography measurements of the phase dispersion that is induced by the scattering process. We use both Mie scattering predictions and dispersion measurements of phantoms to show that the scattering dispersion is very sensitive to small changes in the size and/or refractive index of the scatterer. We also show the light scattered from a single sphere is, in some cases, non-minimum phase. Therefore, the phase is independent of the intensity of the scattered light, and both intensity and phase must be measured directly in order to characterize more completely the scattering problem. Phase dispersion measurements may have application to distinguishing the size and refractive index of scattering particles in biological tissue samples.. ©2006 Optical Society of America. Full Article , PDF Article ...

Asejczyk-Widlicka, Magdelena, Schachar, Ronald A. and Pierscionek, Barbara K. (2008) Optical coherence tomography measurements of the fresh porcine eye and response of the outer coats of the eye to volume increase. Journal of Biomedical Optics, 13(2), 024002. ISSN (print) 1083-3668 ...

Purpose: To determine the choroidal thickness (CT) profile in keratoconus (KC) patients using swept-source optical coherence tomography (SS-OCT). Methods: This was a prospective, cross-sectional study. One hundred two eyes of 52 KC patients were studied using Pentacam and SS-OCT. The macular CT profile was created by manually measuring the distance between the retinal pigment epithelium and the choroid-sclera junction on horizontal b-scans at nine different macular locations. The results were compared to 93 eyes of 93 healthy controls. Results: Mean age of the KC group was 34.9 ± 13.5 years and mean axial length (AL) was 24.1 ± 1.3 mm. Mean topographic KC classification (TKC) was 2.0; 39 eyes were classified as early KC (TKC ,1-2), 34 eyes as moderate (TKC 2, 2-3), and 29 as advanced (TKC 3+). Mean subfoveal CT was 383.2 μm in KC patients and 280.5 μm in control group (P , 0.001). CT in KC patients was statistically thicker in all measure locations (P , 0.001). CT in KC eyes decreased with ...

TY - CHAP. T1 - Modeling light-tissue interaction in optical coherence tomography systems. AU - Andersen, Peter E.. AU - Jørgensen, Thomas Martini. AU - Thrane, Lars. AU - Tycho, Andreas. AU - Yura, H. T.. PY - 2015. Y1 - 2015. KW - Absorption. KW - Light propagation. KW - Light tissue interaction. KW - Optical coherence tomography. KW - Scattering. KW - Theoretical model. U2 - 10.1007/978-3-319-06419-2_4. DO - 10.1007/978-3-319-06419-2_4. M3 - Book chapter. SN - 978-3-319-06418-5. SP - 95. EP - 140. BT - Optical coherence tomography. A2 - Drexler, W.. A2 - Fujimoto, J.G.. PB - Springer. ER - ...

Optical Coherence Tomography Market: Global Historical Growth (2012-2016) & Future Outlook (2017-2024) Demand Analysis & Opportunity Evaluation. The global optical coherence tomography market is segmented into application such as ophthalmology, dermatology, oncology, cardiovascular, dentistry and cancer detection. Among these segments, ophthalmology segment is expected to occupy the top position in overall optical coherence tomography market. Further, the growth of this segment is attributed to various factors such as increasing number of patients affected with eyes disorders such as age-related macular degeneration, diabetic retinopathy, macular edema and others. Apart from this, dermatology segment mask an outstanding CAGR in near future owing to growing skin disorders and continuous technological advancement in the field of optical coherence tomography.. Global optical coherence tomography market is expected to register a 10.9% CAGR over the forecast period. Moreover, the global optical ...

Definition of Optical coherence tomography in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is Optical coherence tomography? Meaning of Optical coherence tomography as a legal term. What does Optical coherence tomography mean in law?

OBJECTIVES: We used optical coherence tomography, which has a resolution of |20 microm, to analyze thin layers of neointima in rapamycin-eluting coronary stents. BACKGROUND: Lack of neointimal coverage has been implicated in the pathogenesis of drug-eluting coronary stent thrombosis. Angiography and intracoronary ultrasound lack the resolution to examine this. METHODS: We conducted a randomized trial in patients receiving polymer-coated rapamycin-eluting stents (Cypher, Cordis, Johnson & Johnson, Miami, Florida) and nonpolymer rapamycin-eluting stents (Yukon, Translumina, Hechingen, Germany) to examine neointimal thickness, stent strut coverage, and protrusion at 90 days. Twenty-four patients (n = 12 for each group) underwent stent deployment and invasive follow-up at 90 days with optical coherence tomography. The primary end point was binary stent strut coverage. Coprimary end points were neointimal thickness and stent strut luminal protrusion. RESULTS: No patient had angiographic restenosis. For

We demonstrate functional in vivo imaging of photoreceptor and neuronal layers within the living human retina by looking at the expansion of their optical path length. To this end, we use a special full-field swept-source optical coherence tomography system that acquires all lateral points in parallel, achieving a high-speed data acquisition with up to 200 volumes per second. A combination of computational motion and aberration correction with a suitable phase evaluation scheme yields minuscule changes after exposing the photoreceptors to a white light stimulus ...

TY - JOUR. T1 - Analysis of the outer retina reconstructed by high-resolution, three-dimensional spectral domain optical coherence tomography. AU - Kaluzny, Jakub J.. AU - Wojtkowski, Maciej. AU - Sikorski, Bartosz L.. AU - Szkulmowski, Maciej. AU - Szkulmowska, Anna. AU - Bajraszewski, Tomasz. AU - Fujimoto, James G.. AU - Duker, Jay S.. AU - Schuman, Joel S.. AU - Kowalczyk, Andrzej. PY - 2009/3. Y1 - 2009/3. N2 - ■ BACKGROUND AND OBJECTIVE: A retrospective cross-sectional study was conducted to demonstrate an analysis of an outer retinal layer reconstructed by the three-dimensional and high-speed spectral domain optical coherence tomography (SD-OCT) instrument. ■ PATIENTS AND METHODS: New measurement protocols for SD-OCT and methods of analysis and visualization of the individual segmented retinal layer reconstructed by SD-OCT were proposed. Three contour maps representing mutual distances between the basal part of the retinal pigment epithelium, the junction between the inner and outer ...

TY - JOUR. T1 - The APOSTEL recommendations for reporting quantitative optical coherence tomography studies. AU - Cruz-Herranz, Andrés. AU - Balk, Lisanne J.. AU - Oberwahrenbrock, Timm. AU - Saidha, Shiv. AU - Martinez-Lapiscina, Elena H.. AU - Lagreze, Wolf A.. AU - Schuman, Joel S.. AU - Villoslada, Pablo. AU - Calabresi, Peter. AU - Balcer, Laura. AU - Petzold, Axel. AU - Green, Ari J.. AU - Paul, Friedemann. AU - Brandt, Alexander U.. AU - Albrecht, Philipp. PY - 2016/6/14. Y1 - 2016/6/14. N2 - Objective: To develop consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results. Methods: A panel of experienced OCT researchers (including 11 neurologists, 2 ophthalmologists, and 2 neuroscientists) discussed requirements for performing and reporting quantitative analyses of retinal morphology and developed a list of initial recommendations based on experience and previous studies. The list of recommendations was subsequently revised during several ...

Imaging choroidal neovascular membrane using en face swept-source optical coherence tomography angiography Magdy Moussa,1,2 Mahmoud Leila,3 Hagar Khalid1,2 1Ophthalmology Department, Faculty of Medicine, Tanta University, Tanta, Egypt; 2MEDIC Eye Center, Tanta, Egypt; 3Retina Department, Research Institute of Ophthalmology, Giza, Egypt Purpose: The aim of this study was to assess the efficacy of swept-source optical coherence tomography angiography (SS-OCTA) in delineating the morphology of choroidal neovascular membrane (CNV). Patients and methods: This was a retrospective observational case series reviewing clinical data and fundus fluorescein angiography (FFA), swept-source optical coherence tomography (SS-OCT), and SS-OCTA images of patients with CNV and comparing the findings. The swept-source technology enables deeper penetration and superior axial resolution. The incorporated blood flow detection algorithm, optical coherence tomography angiography ratio analysis (OCTARA), enables visualization

Purpose: The purpose of this study was to cluster the test points of the combined 24-2 and 10-2 visual fields (VFs) and circumpapillary retinal nerve fiber layer thickness (cpRNFLT) sectors using explanatory factor analyses (EFAs). The correlations between the VF clusters and cpRNFLT clusters were determined, and a new function-structure relationship map was determined. Methods: Two hundred fifty-four eyes of 166 subjects (13 normal eyes and 241 eyes with glaucoma) were studied retrospectively. All eyes had an axial length ,27 mm and had undergone 24-2 and 10-2 VF tests using the Swedish Interactive Threshold Algorithm (SITA-standard) and cpRNFLT examinations by spectral domain optical coherence tomography within a 3-month period. Explanatory factor analysis was performed to group the 116 test points of the combined 24-2/10-2 VF test grids into a smaller number of VF clusters. Another EFA was performed to cluster the 24 cpRNFLT sectors. The correlations between the VF clusters and the cpRNFLT ...

Authors: Ian C. Han, MD1; S. Scott Whitmore, PhD1; D. Brice Critser, BS, CRA1; Edwin M. Stone, MD, PhD1. Author Affiliations: 1Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA 52242. Purpose: Choroideremia is an X-linked condition characterized by profound choroidal thinning and outer retinal loss which typically begin peripherally and spare the central macula until later in the disease course. The depth of imaging and wide field of view enabled by swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA) may be advantageous for characterizing the extent of pathology deep to the choroid and beyond the macula. We aim to describe SS-OCT and SS-OCTA findings in a cohort of patients with choroideremia. Methods: This is a retrospective, cross-sectional study of consecutive patients with molecularly-confirmed choroideremia seen at a tertiary referral center from September 12, 2017 to September 11, 2018. All patients ...

Authors: Nesrine Abroug, Imen Ksiaa, Hager Ben Amor, Bechir Jelliti, Sana Khochtali, Moncef Khairallah Affiliation: Department of Ophthalmology, Fattouma Bourguiba University Hospital, Faculty of Medicine, University of Monastir, Monastir, Tunisia. Clinical presentation: A 65-year-old diabetic man with a history of fever of unknown origin two weeks earlier complained of sudden decreased vision in the left eye. The patient was diagnosed with bilateral West Nile virus (WNV) chorioretinitis associated with occlusive retinal vasculitis in the left eye. He was evaluated using Swept-source optical coherence tomography angiography (SS OCTA). Imaging findings: SSOCTA of the left eye showed extensive well-delineated hypointense greyish areas of retinal capillary hypoperfusion and perifoveal capillary arcade disruption in the superficial capillary plexus, and larger greyish areas of capillary hypoperfusion, capillary rarefaction, and diffuse capillary network attenuation and disorganization in the deep ...

The Worldwide Optical Coherence Tomography Market is growing with the rapid pace; mainly due the burgeoning Healthcare Sector. According to a recent study report published by the Market Research Future, The World Optical Coherence Tomography Market is booming and expected to gain prominence over the forecast period. The Market is forecasted to demonstrate a huge growth by 2023, surpassing its previous growth records in terms of value & volume. The World Market research report of Optical Coherence Tomography is expected to reach US$ 1.59 billion in 2023 from US$ 0.14 billion in 2016 with a CAGR of approximately 8.2% during the forecast period 2017-2023.. Market Research Future published new report, titled Optical Coherence Tomography Market -Research Report: Forecast to 2023.. Some of the Key Players in this market are: Carl Zeiss Meditec AG, Heidelberg Engineering GmbH and Agfa Healthcare. Other players in this market are: Imalux Corporation, Michelson Diagnostics, Novacam Technologies Inc. ...

The Worldwide Optical Coherence Tomography Market is growing with the rapid pace; mainly due the burgeoning Healthcare Sector. According to a recent study report published by the Market Research Future, The World Optical Coherence Tomography Market is booming and expected to gain prominence over the forecast period. The Market is forecasted to demonstrate a huge growth by 2023, surpassing its previous growth records in terms of value & volume. The World Market research report of Optical Coherence Tomography is expected to reach US$ 1.59 billion in 2023 from US$ 0.14 billion in 2016 with a CAGR of approximately 8.2% during the forecast period 2017-2023.. Market Research Future published new report, titled Optical Coherence Tomography Market -Research Report: Forecast to 2023.. Some of the Key Players in this market are: Carl Zeiss Meditec AG, Heidelberg Engineering GmbH and Agfa Healthcare. Other players in this market are: Imalux Corporation, Michelson Diagnostics, Novacam Technologies Inc. ...

TY - GEN. T1 - Medical applications of polarization-sensitive optical coherence tomography. AU - Kim, Beop Min. PY - 2008. Y1 - 2008. KW - Birefringence. KW - Collagen fibers. KW - Optical diagnosis. KW - Polarization-sensitive optical coherence tomography (PS-OCT). KW - Scattering measurements. UR - http://www.scopus.com/inward/record.url?scp=58049180565&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=58049180565&partnerID=8YFLogxK. U2 - 10.1109/LEOS.2008.4688507. DO - 10.1109/LEOS.2008.4688507. M3 - Conference contribution. AN - SCOPUS:58049180565. SN - 9781424419326. T3 - Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS. SP - 99. EP - 100. BT - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, LEOS 2008. T2 - 21st Annual Meeting of the IEEE Lasers and Electro-Optics Society, LEOS 2008. Y2 - 9 November 2008 through 13 November 2008. ER - ...

We describe the spectral domain optical coherence tomography (SD-OCT) findings in three patients with acute syphilitic posterior placoid chorioretinitis (ASPPC). The SD-OCT images demonstrate the pathologic changes in ASPPC with a high level of anatomic detail and may provide information about the pathophysiology of the disease. We report a series of three consecutive patients seen at the Wilmer Eye Institute in 2012 and 2013 who presented with clinical and laboratory findings consistent with a diagnosis of unilateral ASPPC. Two of the three patients had HIV co-infection with good immune recovery. SD-OCT images from their initial (pre-treatment) presentation demonstrated thickening and hyperreflective nodularity of the choroid-retinal pigment epithelium (RPE) complex, with focal disruption of the overlying photoreceptor inner segment-outer segment junction in the areas corresponding to the retinal lesions seen on clinical examination. These changes improved with intravenous antibiotic treatment over a 3

Purpose: To identify and compare possible changes in intraocular pressure (IOP), macular and peripapillary retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) before and after 3 months of positive airway pressure (PAP) in patients with severe OS...

The development of high-resolution and high-speed OCT technology as well as OCT compatible catheter/endoscopes and other delivery systems represent the future of OCT imaging clinical applications. The unique capabilities of OCT imaging make it an ideal choice for the diagnosis and clinical management of many diseases. In 2015, the total revenue of the intravascular OCT market was $128 million; it increased to $140 million in 2016. The primary factors contributing in the growth of the Optical Coherence Tomography (OCT) market is growing aging population and extensive application scope of the technology. Moreover, technological benefits of OCT such as ability to visualize in-depth structures of the eye, mucosal membranes, surface tissues and vascular systems; is significantly driving the growth of the Optical Coherence Tomography (OCT) market. Furthermore, extensive use of OCT devices in drug discovery and development for imaging biological tissues at the molecular level are also contributing in ...

Macular edema is a common cause of visual loss at uveitic patients. The aim of our study was to investigate retinal and choroidal thickness at the macula in anterior (AU) and intermediate (IMU) uveitis and in healthy individuals using spectral domain optical coherence tomography (SD-OCT). Case-control study of 21 patients with AU and 23 patients with IMU and 34 age-matched healthy controls was performed with Spectralis SD-OCT (Heidelberg Engineering, Germany). High resolution SD-OCT scans and macular mapping were applied for automated measurement of retinal thickness. Standardized, masked manual measurement of the choroidal thickness was performed in the center of the ETDRS fields on enhanced depth imaging (EDI) scans. Evaluation of central retinal subfield thickness, 3 mm and 6 mm perifoveal rings was performed in the corresponding ETDRS zones in patient groups. The mean central retinal subfield thickness was significantly higher in IMU (368.65 ± 115.88 μm, p = 0.0003), but not significantly

Purpose: To describe a technique to obtain combined images of vitreoretinal and choroidal structures using spectral-domain (SD) optical coherence tomography (OCT) and to evaluate applicability in normal eyes and limitations in eyes with cataract. Design: Prospective, observational case series. Methods: Three different foveal scans, including conventional SD OCT, enhanced depth imaging OCT and the novel method called combined depth imaging (CDI) OCT, were obtained in 42 eyes of healthy volunteers and in 26 eyes with cataract using the Heidelberg Spectralis HRA (Heidelberg Engineering). The CDI OCT images were obtained manually using an image modification process that enhances the vitreoretinal interface first and then the choroid, while averaging 100 separate OCT scans. The visualization of the inner border of the preretinal pocket and the outer border of the choroid was graded by independent masked observers for each OCT scan method. Results: The CDI technique was able to create a good-quality ...

BACKGROUND: To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness in glaucomatous Nepalese eyes using spectral domain optical coherence tomography (SD-OCT) and study its relationship with visual field sensitivity. METHODS: A total of 120 eyes comprising primary open angle glaucoma (POAG), glaucoma suspects (GS), normal tension glaucoma (NTG) and healthy subjects (n=30 cases in each group) underwent a complete ophthalmic examination, including optic nerve head (ONH) evaluation and standard automated perimetry (SAP). RNFL thickness measurements around the optic disk were taken with circular spectral domain optical coherence tomography (SD-OCT) scans. Analysis of variance (ANOVA) was used for comparison of RNFL parameters among various study groups. The relationship of RNFL parameters with visual field (VF) global indices was evaluated with regression analysis. RESULTS: The mean pRNFL thickness was significantly less in the POAG (64.30±14.45μm, p,0.01), NTG (85.43±9.79μm, ...

TY - GEN. T1 - Ultrahigh-speed ultrahigh-resolution adaptive optics. T2 - Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XVII. AU - Jian, Yifan. AU - Xu, Jing. AU - Zawadzki, Robert. AU - Sarunic, Marinko V.. PY - 2013/5/22. Y1 - 2013/5/22. N2 - Small animal models of human retinal diseases are a critical component of vision research. In this report, we present an ultrahigh-resolution ultrahigh-speed adaptive optics optical coherence tomography (AO-OCT) system for small animal retinal imaging (mouse, fish, etc.). We adapted our imaging system to different types of small animals in accordance with the optical properties of their eyes. Results of AO-OCT images of small animal retinas acquired with AO correction are presented. Cellular structures including nerve fiber bundles, capillary networks and detailed double-cone photoreceptors are visualized.. AB - Small animal models of human retinal diseases are a critical component of vision research. In this report, we ...

Computerized Assessment of Intraretinal and Subretinal Fluid Regions in Spectral-Domain Optical Coherence Tomography Images of the Retina

Optical coherence tomography (OCT) is an imaging method which can image with micrometer-scale resolution up to a few millimeters deep into, for example, living biological tissues and preserved tissue samples. An improved apparatus and image reconstruction algorithm for parallel Fourier Domain OCT which greatly eases requirements for interferometer stability and also allows for more efficient parallel image acquisition is provided. The apparatuses and algorithms reconstruct images from interfered, low-coherence, multiwave length signals having a π radian phase difference relative to one another. Other numbers of signals and other phase differences may be alternatively used, with some combinations resulting in higher resolution and image stability. The apparatus also eliminates a need for bulk optics to modulate a phase delay in a reference arm of the optical path. Images may be reconstructed using two spectrometers, where each is coupled to a detector array such as a photodiode array.

Color Doppler optical coherence tomography (CDOCT) is a noninvasive optical imaging technique for micro-meter-scale physiological flow mapping simultaneously with morphological optical coherence tomography imaging. We have developed a novel CDOCT signal-processing strategy capable of imaging physiological flow rates at 8 frames/s. Our new strategy features hardware-implemented digital autocorrelation across subsequent scans, permitting us to measure 300-Hz-8-kHz Doppler shifts upon signals of 0.6-MHz bandwidth. The performance of the CDOCT system was demonstrated in a flow phantom and in vivo in Xenopus laevis.. © 2002 Optical Society of America. Full Article , PDF Article ...

TY - JOUR. T1 - Visual acuity and perimacular retinal layers detected by optical coherence tomography in patients with retinitis pigmentosa. AU - Matsuo, Toshihiko. AU - Morimoto, Noriko. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2007/7. Y1 - 2007/7. N2 - Background: The remaining retinal neurones or layered structure in the degenerating retina have been the prerequisite for epiretinal or subretinal retinal prostheses. Aim: To detect the layered structure in the eyes of patients with retinitis pigmentosa by optical coherence tomography. Methods: In a prospective non-comparative study, 115 eyes of 58 consecutive patients with retinitis pigmentosa underwent optical coherence tomography to obtain horizontal and vertical retinal cross-section images at the centre of the macula. The number of high-reflectance retinal layers, one, two or three layers, was tested to determine whether it correlates with best-corrected visual acuity. Results: The best-corrected visual ...

Christensen UC, Krøyer K, Sander B, Larsen M, la Cour M. Ophthalmology. 2009 Dec;116(12):2430-6. Christensen UC, Krøyer K, Sander B, Jorgensen TM, Larsen M, la Cour M.Macular morphology and visual acuity after macular hole surgery with or without internal limiting membrane peeling. Br J Ophthalmol. 2010 Jan;94(1):41-7 Fujiwara T, Imamura Y, Margolis R, Slakter JS, Spaide RF. Enhanced depth imaging optical coherence tomography of the choroid in highly myopic eyes. Am J Ophthalmol. 2009 Sep;148(3):445-50. Hirata M, Tsujikawa A, Matsumoto A, Hangai M, Ooto S, Yamashiro K, Akiba M, Yoshimura N. Macular choroidal thickness and volume in normal subjects measured by swept-source optical coherence tomography. Invest Ophthalmol Vis Sci. 2011 Jul 1;52(8):4971-8 Marschall S, Sander B, Mogensen M, Jørgensen TM, Andersen PE. Optical coherence tomography-current technology and applications in clinical and biomedical research. Anal Bioanal Chem. 2011 Jul;400(9):2699-720. Sander B, Larsen M, Thrane L, ...

TY - JOUR. T1 - Longitudinal optical coherence tomography study of optic atrophy in secondary progressive multiple sclerosis. T2 - Results from a clinical trial cohort. AU - Winges, Kimberly. AU - Murchison, Charles F.. AU - Bourdette, Dennis. AU - Spain, Rebecca. PY - 2017/11/1. Y1 - 2017/11/1. N2 - Background: Limited prospective information exists regarding spectral-domain optical coherence tomography (SD-OCT) in secondary progressive multiple sclerosis (SPMS). Objective: Document cross-sectional and longitudinal retinal nerve fiber layer (RNFL) and macular ganglion cell plus inner plexiform layer (GCIPL) features of an SPMS clinical trial cohort. Methods: Prospective, observational study using a 2-year randomized placebo-controlled SPMS trial cohort with yearly SD-OCT testing. Post hoc analysis determined influences of optic neuritis (ON), disease duration, and baseline SD-OCT on annualized atrophy rates and on correlations between OCT and brain atrophy. Results: Mean RNFL and GCIPL values ...

TY - JOUR. T1 - Role of high resolution optical coherence tomography in diagnosing ocular surface squamous neoplasia with coexisting ocular surface diseases. AU - Atallah, Marwan. AU - Joag, Madhura. AU - Galor, Anat. AU - Amescua, Guillermo. AU - Nanji, Afshan. AU - Wang, Jianhua. AU - Perez, Victor L.. AU - Dubovy, Sander. AU - Karp, Carol L.. N1 - Funding Information: Supported by the NIH Center Core Grant P30EY014801 , RPB Unrestricted Award and Career Development Awards, Department of Defense (DOD- Grant# W81XWH-09-1-0675 ), Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Clinical Sciences Research EPID-006-15S (Dr. Galor), The Ronald and Alicia Lepke Grant, The Lee and Claire Hager Grant, The Jimmy and Gaye Bryan Grant, The Azar Family Grant, The Robert Baer Family Grant, The Gordon Charitable Foundation, The H. Scott Huizenga Grant, The Grant and Diana Stanton-Thornbrough Grant, The Mark Feldberg Family Grant, and supported in part by an ...

TY - JOUR. T1 - Wavefront sensorless modal deformable mirror correction in adaptive optics. T2 - Optical coherence tomography. AU - Bonora, S.. AU - Zawadzki, Robert. PY - 2013/11/15. Y1 - 2013/11/15. N2 - We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and application of the resulting shapes to a deformable mirror, while optimizing using image sharpness as a merit function. We demonstrate that this technique can compensate for aberrations induced by trial lenses. Measurements of the point spread function before and after compensation demonstrate near diffraction limit imaging.. AB - We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and ...

Blood flow measurement with spectrometer-based Fourier domain optical coherence tomography (FD-OCT) is limited by the motion-induced signal fading and the resulting reduction of flow sensitivity. Therefore, we have numerically simulated the signal power decrease of an obliquely moved scattering layer as a function of the absolute sample velocity composed of an axial and transverse component. In contrast to the prevalent expectance, the resulting signal damping is not only the sum of axial and transverse effect. In this study, we take advantage of the signal decay and present the feasibility to quantify high flow velocities at which the standard Doppler OCT does not work any longer. For the validation of our approach, a flow phantom model consisting of a 1%-Intralipid solution and a 320 μm glass capillary was used. With this phantom study, depth-resolved flow was visualized and the quantitative velocities were extracted from the OCT images without phase information ...

Ophthalmologists usually use slit lamp biomicroscopy to look for Kayser-Fleischer rings in Wilsons disease; anterior segment optical coherence tomography is a new alternative to identify the characteristic hyper-reflective layer in the deep corneal periphery at the level of Descemets membrane. This method allows non-ophthalmologists to look for and to quantify Kayser-Fleischer rings. ...

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Abstract Importance Novel therapies for choroideremia, an X-linked recessive chorioretinal degeneration, demand a better understanding of the primary site(s) of cellular degeneration. Optical coherence tomography angiography allows for choriocapillaris (CC) imaging. We compared the extent of structural alterations of the CC, retinal pigment epithelium, and photoreceptors with multimodal imaging. Observations In a clinical case series conducted from September 15, 2014, through February 5, 2015, 14 eyes of 7 male patients with choroideremia (median age, 34 years [interquartile range, 15-46 years]; age range, 13-48 years), 4 eyes of 2 women with choroideremia carrier state (both in mid-50s), and 6 eyes of 6 controls (median age, 42.5 years [interquartile range, 33-55 years]; age range, 24-55 years) underwent multimodal imaging with optical coherence tomography angiography and electroretinography. The mean (SD) macular CC density was 82.9% (13.4%) in patients with choroideremia, 93.0% (3.8%) in female

PURPOSE: Choroideremia is a rare degenerative retinal disease that causes incurable blindness. It occurs as a result of the deficiency of the X-linked CHM gene, which encodes the Rab escort protein 1 (REP1). Gene therapy has been developed to treat CHM using adeno-associated viral vectors and is currently undergoing clinical trials. Expression of the CHM gene is ubiquitous throughout the retina, and it is therefore important to identify which retinal layers are affected in the disease process. The purpose of this study was to assess in particular the choriocapillaris using optical coherence tomography angiography because this layer is difficult to see with conventional imaging techniques. METHODS: Six men with choroideremia were identified and underwent standardized optical coherence tomography angiography as part of an ethics-approved clinical study and were compared with age-matched control subjects. RESULTS: The choriocapillaris appeared normal in regions where the retinal pigment epithelium remained

The Effect of Soft Contact Lenses During the Measurement of Retinal Nerve Fiber Layer Thickness Using Optical Coherence Tomography

Glaucoma is presumed to be an axonal disease which starts at the lamina cribrosa. This assumption has led to the monitoring of the retinal nerve fiber layer thickness for the diagnosis and monitoring of progression of glaucoma. However, varying disc size, myopia and tilted discs affect the thickness of the retinal nerve fiber layer. This study aims to ascertain the ration of the retinal nerve fiber layer against full retina as a predictor of glaucoma diagnosis and progression ...

Aims To determine the retinal nerve fibre layer (RNFL) thickness at which visual field (VF) damage becomes detectable and associated with structural loss. Methods In a prospective cross-sectional study, 72 healthy and 40 glaucoma subjects (one eye per subject) recruited from an academic institution had VF examinations and spectral domain optical coherence tomography (SD-OCT) optic disc cube scans (Humphrey field analyser and Cirrus HD-OCT, respectively). Comparison of global mean and sectoral RNFL thicknesses with VF threshold values showed a plateau of threshold values at high RNFL thicknesses and a sharp decrease at lower RNFL thicknesses. A broken stick statistical model was fitted to global and sectoral data to estimate the RNFL thickness tipping point where the VF threshold values become associated with the structural measurements. The slope for the association between structure and function was computed for data above and below the tipping point. Results The mean RNFL thickness ...

Results RNFL thickness values, except for lower and upper nasal sectors, were thinner in the myopic eyes than in the hyperopic eyes. Average RNFL thickness and the RNFL thicknesses of the superotemporal, superonasal, inferotemporal and lower temporal sectors were significantly different between the myopic and emmetropic eyes, and average RNFL thickness and the RNFL thicknesses of the upper temporal and inferonasal sectors were significantly different between the hyperopic and emmetropic eyes. The average peripapillary RNFL thickness had a negative correlation with axial length (r=−0.741, p,0.001). However, after correction of the magnification effect, the significant differences disappeared.. ...

Optical coherence tomography; Retinal nerve fiber layer thickness; Macular volume; Parkinson disease; PD; Progressive supranuclear palsy; ...

Optical coherence tomography (OCT) is an imaging modality analogous to ultrasound, but instead of using the difference in the flight times of acoustic waves (as in ultrasound), it uses light to achieve micrometer axial resolution. OCT is used in many different biomedical applications, with retinal imaging being the most successful and the driving force behind much OCT development. The axial resolution of OCT in retinal tissue is about 1-15 µm, which is 10 to 100 times better than ultrasound or MRI. Although relatively new to ophthalmology, a commercial OCT system has already revolutionized the field, rapidly becoming an essential tool in the diagnosis and monitoring of human retinal disease. As part of our collaboration with the Biomedical Engineering Department at Duke University, our group at the Vision Science and Advanced Retinal Imaging Laboratory has developed a Fourier-domain OCT system that is faster and has higher resolution than existing commercial OCT instruments. In collaboration ...

To Study the correlation between fundus fluorescein angiography and optical coherence tomography patterns in clinically significant macular oedema

Generally, the measurements for the drusen area and volume from SS-OCTA were larger than those from SD-OCT. In the center 3 mm circle, the mean drusen area measurements were 1.52 mm2 and 2.11 mm2 from the SD-OCT and SS-OCTA scans, respectively, and the mean square root of the drusen area measurements were 1.17 mm and 1.39 mm from the SD-OCT and SS-OCTA scans, respectively. In the 5 mm circle, the mean drusen area measurements were 1.89 mm2 and 2.67 mm2 from the SD-OCT and SS-OCTA scans, respectively, and the mean square root of drusen area measurements were 1.28 mm and 1.54 mm from the SD-OCT and SS-OCTA scans, respectively. Similarly, the cube root drusen volumes were larger from the SS-OCTA scans. In the center 3 mm circle, the mean drusen volume measurements were 0.09 mm3 and 0.13 mm3 from the SD-OCT and SS-OCTA scans, respectively, and the mean cube root of drusen volume measurements were 0.41 mm and 0.47 mm from the SD-OCT and SS-OCTA scans, respectively. In the center 5 mm circle, the mean ...

Purpose the objective of this paper is to describe the optical coherence tomography (OCT) characteristics of patients with full-thickness traumatic macular hole (TMH) and to correlate them with biomicroscopy findings.Methods Twelve eyes of ten consecutive patients with full-thickness TMH participated in this observational retrospective multicentre study. Patients underwent biomicroscopic fundus examination, colour fundus photography, and OCT.Results Traumatic macular hole was documented with OCT in five women and five men. Mean (range) time between trauma and macular hole (MH) diagnosis was 8.1 (1-24) months. the shape of TMHs was round in 11 (91.7%) eyes. the posterior vitreous was completely detached in six (50%) eyes, and with an operculum in one (8.3%) eye. the common findings seen on OCT were: (1) full-thickness loss of retinal tissue through the hole with sharp edges, perpendicular to the retinal pigment epithelium in five (41.7%) eyes; (2) TMH with an operculum totally detached from the ...

Mark Dunbar, OD, discusses his recent lecture on optical coherence tomography (OCT) technology. He highlights the increasing need to have OCT in an optometry office, emphasizing its importance for diagnosing vitreomacular disease as well as glaucoma.

PURPOSE: To present a technique of ocular sectioning that enables continuous histologic measurements of peripapillary retinal nerve fiber layer (RNFL) thickness in a concentric ring around the optic disc, corresponding to similar regions measured by in vivo imaging techniques.. METHODS: Two pig eyes and two normal human eyes were processed using the umbrella technique, in which peripapillary concentric ring sections were obtained, at increasing diameters, all centered on the optic disc. Each histologic ring section contains a continuous circumferential 360 degrees retinal slice, oriented approximately perpendicular to the retinal surface. Every histologic slice contains each axon of the retina, sectioned perpendicular to each axons long axis and at an equal set distance from the disc margin.. RESULTS: Ring sections from pig and human eyes are presented and correlated to known RNFL anatomy. For the two human eyes, peripapillary RNFL thickness was quantified and plotted, resulting in the ...

To evaluate choroidal vascular changes, including choriocapillaris (CC) and middle/large choroidal vessels, in retinitis pigmentosa (RP) patients using wide-angle optical coherence tomography angiography (OCTA) and to determine whether changes in the choroidal vascularity have a relationship with visual function and retinal structural changes. 34 patients with a confirmed diagnosis of RP and 48 controls were recruited. All patients underwent detailed ophthalmologic and imaging examinations, including two types of OCTA (Optovue, 3 × 3 mm, 6 × 6 mm; VG-200, 12 × 12 mm). CC defects were defined according to the choroidal vascular structure in five degrees. To evaluate middle and large choroidal vascular changes, the choroidal vascularity index (CVI), which was the luminance volume to the total choroidal volume, was used. Defects of choroidal vascularity of RP eyes were detected in comparison to control eyes. The defects were observed in the CC layer with a concentric or lobular pattern at different

Purpose: The purpose of this study was to define the morphologic differences in idiopathic and secondary epiretinal membranes (ERMs) using a time domain optical coherence tomography. ...

The National Institute on Deafness and Other Communication Disorders (NIDCD) supports research and development of innovative technologies for improving the qual...

Relative sensitivity and specificity of 10-2 visual fields, multifocal electroretinography, and spectral domain optical coherence tomography in detecting hydroxychloroquine and chloroquine retinopathy David J Browning, Chong Lee Charlotte Eye, Ear, Nose and Throat Associates, Charlotte, NC, USA Background: The purpose of this study was to determine the relative sensitivity and specificity of 10-2 visual fields (10-2 VFs), multifocal electroretinography (mfERG), and spectral domain optical coherence tomography (SD-OCT) in detecting hydroxychloroquine retinopathy.Methods: A total of 121 patients taking hydroxychloroquine (n=119) or chloroquine (n=2) with 10-2 VF, mfERG, and SD-OCT tests were retrospectively reviewed. Rates of test abnormality were determined.Results: Retinopathy was present in 14 and absent in 107. Eleven of 14 (78.6%) patients with retinopathy were overdosed. Twelve (85.7%) had cumulative dosing greater than 1,000 g. The sensitivities of 10-2 VF, mfERG, and SD-OCT in detecting