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Ophthalmology Sep 2019To review the published literature on the use of swept-source (SS) OCT for evaluating the lamina cribrosa in glaucoma. (Review)
Review
PURPOSE
To review the published literature on the use of swept-source (SS) OCT for evaluating the lamina cribrosa in glaucoma.
METHODS
A PubMed and Cochrane Library literature search initially conducted on March 3, 2017, and updated on June 26, 2018, yielded a total of 64 articles. Articles that were reviews or that were not published in English were excluded, and 29 were found to fit the inclusion criteria. The panel methodologist then assigned a level of evidence rating to each study. Fifteen studies were rated level III, 14 studies were rated level II, and no studies were rated level I.
RESULTS
Different aspects of the lamina cribrosa were studied using SS-OCT, including the anterior lamina cribrosa curvature, anterior lamina cribrosa depth, anterior lamina cribrosa insertions, laminar thickness, focal lamina cribrosa defects (FLCDs), and lamina cribrosa microarchitecture. In general, imaging of the anterior lamina can be achieved reliably, although shadowing from blood vessels at the neuroretinal rim remains an issue. Imaging of the posterior lamina can be achieved with varying levels of success. In glaucoma, there is posterior migration of the anterior lamina cribrosa insertions as well as increased thinning and posterior curvature of the lamina cribrosa. Focal lamina cribrosa defects appear more commonly in glaucoma, and this may hint at the pathogenesis of axonal damage. In addition, there may be remodeling of the microarchitecture of the lamina, resulting in more variable laminar pores. There are limited studies comparing SS-OCT with spectral-domain (SD) OCT with regard to imaging of the lamina, but the difference in image quality between enhanced depth imaging (EDI) with SD-OCT and SS-OCT seems minimal.
CONCLUSIONS
Imaging of the lamina cribrosa using SS-OCT has demonstrated that the lamina cribrosa is likely biomechanically active and that significant changes occur in glaucoma. The diagnostic utility of SS-OCT for lamina cribrosa imaging is promising, but standardized nomenclature, automated measurements, and longitudinal studies with larger and more diverse sample sizes are needed.
Topics: Academies and Institutes; Databases, Factual; Glaucoma, Open-Angle; Humans; Nerve Fibers; Ophthalmology; Optic Disk; Optic Nerve Diseases; Retinal Ganglion Cells; Technology Assessment, Biomedical; Tomography, Optical Coherence; United States
PubMed: 30953743
DOI: 10.1016/j.ophtha.2019.03.044 -
Eye (London, England) Nov 2019We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer...
OBJECTIVES
We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer (RNFL).
METHODS
Healthy control patients underwent enhanced depth imaging (EDI) by spectral-domain optical coherence tomography (OCT) before and 30 min after phenylephrine instillation, using eye-tracking and follow-up software. Changes in 14 different locations of CT, 2 locations of pCT and RNFL were assessed.
RESULTS
The study included 119 eyes of 62 patients (19 males and 43 females), with a mean age of 59.8 ± 15.3 years (range: 26-88 years). Within 30 min after instillation, the mean subfoveal CT both in vertical and horizontal scan were significantly thinned (p = 0.005 and p = 0.018, respectively). In total, 1500, 1000 and 500 µm temporal CT measurements showed also a significant thinning (p = 0.021, p = 0.037 and p = 0.020, respectively), as well as 500 µm both superior (p = 0.045) and inferior (p = 0.009). 1500, 1000 and 500 µm nasal CT, and 1500 and 1000 µm CT superior and inferior measurements showed no significant thinning after phenylephrine instillation. pCT was significantly thinned after phenylephrine in both superior (p = 0.016) and inferior (p = 0.050) measurements. RNFL analysis did not significantly change after phenylephrine instillation (p = 0.209).
CONCLUSIONS
A significant thinning of CT and pCT occurred following phenylephrine instillation. Future studies analysing CT and pCT should detail if this mydriatic agent was used or not.
Topics: Administration, Ophthalmic; Adult; Aged; Aged, 80 and over; Choroid; Female; Healthy Volunteers; Humans; Macula Lutea; Male; Middle Aged; Mydriatics; Nerve Fibers; Ophthalmic Solutions; Optic Disk; Phenylephrine; Pupil; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 31164729
DOI: 10.1038/s41433-019-0478-z -
Investigative Ophthalmology & Visual... Jun 2022To investigate the characteristics of the optic nerve head (ONH) in myopia using swept-source optical coherence tomography (SS-OCT).
PURPOSE
To investigate the characteristics of the optic nerve head (ONH) in myopia using swept-source optical coherence tomography (SS-OCT).
METHODS
Participants were divided into three groups according to the axial length (AL). The optic disc morphology, retinal nerve fiber layer (RNFL) thickness, and radial peripapillary capillary (RPC) vessel density (VD), optic disc tilt, rotation, Bruch's membrane opening distance (BMOD), border length (BL), border tissue angle, focal lamina cribrosa (LC) defects, β- and γ-zone peripapillary atrophy (PPA), microvasculature dropout (MvD), choroidal thickness (CT), and the choroidal vascularity index (CVI) were compared. Linear regression analysis evaluated relationships between spherical equivalent, AL, and ONH parameters.
RESULTS
One hundred five, 98, and 118 eyes were included in groups 1, 2, and 3, respectively. With AL increasing, the mean, superior and temporal CT, central mean and temporal, pericentral mean, inferior and nasal RPC VD, and temporal CVI decreased, whereas the mean and temporal RNFL thickness, optic disc, RIM and β-PPA area, presence and area of γ-PPA, BMOD and BL increased. Compared to other groups, group 3 depicted a larger cup area, more focal LC defect and total and juxtapapillary MvD; a lower central superior, inferior and nasal, pericentral superior, and temporal RPC VD. Group 1 demonstrated more tilted disc, larger inferior and nasal CT, mean, superior, inferior, and nasal CVI.
CONCLUSIONS
Myopia eyes have larger ONH changes, PPAs, regional RNFL, and MvD, but smaller regional CTs, RPC VD, and CVIs. SS-OCT may be useful in detecting ONH variations during myopia.
Topics: Bruch Membrane; Humans; Myopia; Optic Disk; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35731511
DOI: 10.1167/iovs.63.6.20 -
Eye (London, England) Oct 2021To evaluate the distribution of macula and circumpapillary retina nerve fiber layer (cpRNFL) thickness and other associated factors among grade-1 primary school children...
OBJECTIVE
To evaluate the distribution of macula and circumpapillary retina nerve fiber layer (cpRNFL) thickness and other associated factors among grade-1 primary school children in Lhasa using spectral-domain optical coherence tomography (SD-OCT).
METHODOLOGY
OCT assessment was conducted on 1856 grade-1 students from 7 primary schools in Lhasa, Tibet following a successful random stratified sampling of the students. Each child underwent comprehensive general and ocular examinations as well as an SD-OCT detection (12 × 9 mm, 3D wide scan mode, Topcon 3D OCT-1) to assess the thickness of the macula, ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and cpRNFL. Multivariate and correlation analyses were performed to evaluate the association of the demographic and ocular variables.
RESULTS
The average age of the 1762 (94.43%) students who underwent OCT assessment was 6.83 ± 0.46 years. Among them, 984 (53.02%) were boys. The number of students who had macular, cpRNFL, and optic disc scans completed and with adequate image quality were 1412 (82.2%), 1277 (74.4%), and 1243 (72.4%), respectively. The average macula full retinal thickness (FRT), GCIPL, GCC, and cpRNFL thickness of the students was 279.19 ± 10.61 μm, 76.41 ± 4.70 μm, 108.15 ± 6.15 μm, and 112.33 ± 13.5 μm, respectively. Multivariate regression and correlation analysis further revealed that boys and girls had significant differences in their average cpRNFL thickness. Moreover, GCC and GCIPL thickness was negatively correlated with IOP but positively correlated with the body mass index. The thickness of all the layers of the macula and cpRNFL were positively correlated with spherical equivalent. Further to this, the average macular FRT, GCIPL, and GCC thicknesses were positively correlated with cpRNFL global thickness.
CONCLUSION
This study describes the normal distribution of macular retina, cpRNFL, and optic disc parameters in grade-1 Tibetan children in Lhasa. It contributes to the establishment of a normative ophthalmology database of Tibetan children, and advances the ability of OCT in ophthalmic disorder diagnosis during long-term monitoring in plateau.
Topics: Child; Cross-Sectional Studies; Female; Humans; Macula Lutea; Male; Nerve Fibers; Optic Disk; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 33239762
DOI: 10.1038/s41433-020-01313-z -
American Journal of Ophthalmology Oct 2023We used automated image analysis of scanning laser ophthalmoscopy (SLO) to investigate mechanical strains imposed on disc, and retinal and choroidal vessels during...
PURPOSE
We used automated image analysis of scanning laser ophthalmoscopy (SLO) to investigate mechanical strains imposed on disc, and retinal and choroidal vessels during horizontal duction in adults.
DESIGN
Deep learning analysis of optical images.
METHODS
The peripapillary region was imaged by SLO in central gaze, and 35° abduction and adduction, in younger and older healthy adults. Automated image registration was followed by deep learning-based optical flow analysis to track determine local tissue deformations quantified as horizontal, vertical, and shear strain maps relative to central gaze. Choroidal vessel displacements were observed when fundus pigment was light.
RESULTS
Strains in the retina and disc could be quantified in 22 younger (mean ± SEM, 26 ± 5 years) and 19 older (64 ± 10 years) healthy volunteers. Strains were predominantly horizontal and greater for adduction than for abduction. During adduction, maximum horizontal strain was tensile in the nasal hemi-disc, and declined progressively with distance from it. Strain in the temporal hemi-retina during adduction was minimal, except for compressive strain on the disc of older subjects. In abduction, horizontal strains were less and largely confined to the disc, greater in older subjects, and generally tensile. Vertical and shear strains were small. Nasal to the disc, choroidal vessels shifted nasally relative to overlying peripapillary retinal vessels.
CONCLUSIONS
Strain analysis during horizontal duction suggests that the optic nerve displaces the optic canal, choroid, and peripapillary sclera relative to the overlying disc and retina. This peripapillary shearing of the optic nerve relative to the choroid and sclera may be a driver of disc tilting and peripapillary atrophy.
Topics: Adult; Humans; Aged; Optic Disk; Rotation; Retina; Ophthalmoscopy; Lasers; Tomography, Optical Coherence
PubMed: 37343739
DOI: 10.1016/j.ajo.2023.06.008 -
Philosophical Transactions. Series A,... Mar 2020The optical systems mimicking the eye functions are of great importance in various applications including consumer electronics, medical equipment, machine vision systems... (Review)
Review
The optical systems mimicking the eye functions are of great importance in various applications including consumer electronics, medical equipment, machine vision systems and robotics. This optics offers advantages over traditional optical technologies such as the superior adaptation to changing conditions and the comprehensive range of functional characteristics at miniature sizes. This paper presents a review on the recent progress in the development of human eye-inspired optical systems. Liquid-based and elastomer-based tunable optical elements are discussed with the focus on the actuation mechanism, optical performance and the possibility of integration into artificial eye systems. This article is part of the theme issue 'Bioinspired materials and surfaces for green science and technology (part 3)'.
Topics: Biomimetic Materials; Biomimetics; Electronics; Equipment Design; Eye; Humans; Ocular Physiological Phenomena; Optical Devices; Robotics; Vision, Ocular
PubMed: 32008449
DOI: 10.1098/rsta.2019.0442 -
International Ophthalmology Jul 2022Methamphetamine and crystal methamphetamine abusers were compared with healthy subjects using optical coherence tomography to assess their retinal nerve fiber layer,...
PURPOSE
Methamphetamine and crystal methamphetamine abusers were compared with healthy subjects using optical coherence tomography to assess their retinal nerve fiber layer, macula, and optic disk characteristics.
METHODS
Forty-one methamphetamine and crystal methamphetamine abusers and 42 healthy subjects (mean ± SD of age: 35.82 ± 8.6 and 37.76 ± 9.1 years, respectively) were incorporated in this cross-sectional study. The drug abusers had a history of at least five years of substance use through smoking. Fourier-domain optical coherence tomography was used to image and assess the characteristics of retinal nerve fiber layer, macular thickness, and optic disk in the study groups.
RESULTS
The retinal nerve fiber layer thickness was significantly lower in the superior and temporal retinal quadrants of drug abusers than healthy subjects (P = 0.008 and P = 0.028, respectively). This study did not find a significant difference between drug abusers and healthy controls regarding optic to disk ratio, rim area, and disk area (P > 0.05). The comparison between the study groups showed that the reductions in perifovea and the superior quadrant of parafoveal thickness were statistically significant (P < 0.001 and P = 0.029, respectively).
CONCLUSION
Fourier-domain optical coherence tomography measurements showed that the retinal nerve fiber layer and macular thickness were different between methamphetamine and crystal methamphetamine abusers and healthy subjects, which should be considered in clinical practice. It seems that these drug abuses can cause alterations in retinal morphology.
Topics: Adult; Cross-Sectional Studies; Humans; Macula Lutea; Methamphetamine; Nerve Fibers; Optic Disk; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35188605
DOI: 10.1007/s10792-021-02200-6 -
Ocular Immunology and Inflammation Apr 2021: To measure and compare posterior ocular layers in remission period in children with familial Mediterranean fever (FMF).: A randomly selected eye and fellow eye of 20...
: To measure and compare posterior ocular layers in remission period in children with familial Mediterranean fever (FMF).: A randomly selected eye and fellow eye of 20 FMF patients and 20 control eyes were evaluated. The average age of patients and control subjects were 12.9 ± 2.7 and 13.4 ± 2.7, respectively ( = .57). Peripapillary retinal nerve fiber layer thickness, optic nerve head parameters, macular ganglion cell inner plexiform layer and ganglion cell complex thickness, foveal and parafoveal vascular densities, superficial/deep foveal avascular zone area and choroidal thickness were measured using swept source optical coherence tomography angiography.: Among the overall measurements, temporal quadrant parafoveal vessel density of patients was significantly higher than that of controls (49.20 ± 2.57% vs 47.14 ± 3.17%, = .04) and nasal quadrant vessel density was lower (42.88 ± 4.13% vs 46.76 ± 3.18%, = .02).: This study indicated that FMF as an autoimmune disease may affect foveal vascular structure in children besides multiple other organ involvement.
Topics: Adolescent; Child; Computed Tomography Angiography; Familial Mediterranean Fever; Female; Fovea Centralis; Humans; Male; Nerve Fibers; Optic Disk; Posterior Eye Segment; Retinal Diseases; Retinal Ganglion Cells; Retinal Vessels; Tomography, Optical Coherence
PubMed: 31850808
DOI: 10.1080/09273948.2019.1695857 -
Proceedings of the National Academy of... Sep 2020High-resolution imaging techniques capable of detecting identifiable endogenous fluorophores in the eye along with genetic testing will dramatically improve diagnostic...
High-resolution imaging techniques capable of detecting identifiable endogenous fluorophores in the eye along with genetic testing will dramatically improve diagnostic capabilities in the ophthalmology clinic and accelerate the development of new treatments for blinding diseases. Two-photon excitation (TPE)-based imaging overcomes the filtering of ultraviolet light by the lens of the human eye and thus can be utilized to discover defects in vitamin A metabolism during the regeneration of the visual pigments required for the detection of light. Combining TPE with fluorescence lifetime imaging (FLIM) and spectral analyses offers the potential of detecting diseases of the retina at earlier stages before irreversible structural damage has occurred. The main barriers to realizing the benefits of TPE for imaging the human retina arise from concerns about the high light exposure typically needed for informative TPE imaging and the requirement to correlate the ensuing data with different states of health and disease. To overcome these hurdles, we improved TPE efficiency by controlling temporal properties of the excitation light and employed phasor analyses to FLIM and spectral data in mouse models of retinal diseases. Modeling of retinal photodamage revealed that plasma-mediated effects do not play a role and that melanin-related thermal effects are mitigated by reducing pulse repetition frequency. By using noninvasive TPE imaging we identified molecular components of individual granules in the retinal pigment epithelium and present their analytical characteristics.
Topics: Animals; Biopsy; Disease Models, Animal; Fluorescent Dyes; Mice; Mice, Inbred C57BL; Optical Imaging; Retina; Retinal Diseases; Retinal Pigment Epithelium
PubMed: 32848058
DOI: 10.1073/pnas.2007527117 -
Annual Review of Vision Science Sep 2020High-resolution retinal imaging is revolutionizing how scientists and clinicians study the retina on the cellular scale. Its exquisite sensitivity enables time-lapse... (Review)
Review
High-resolution retinal imaging is revolutionizing how scientists and clinicians study the retina on the cellular scale. Its exquisite sensitivity enables time-lapse optical biopsies that capture minute changes in the structure and physiological processes of cells in the living eye. This information is increasingly used to detect disease onset and monitor disease progression during early stages, raising the possibility of personalized eye care. Powerful high-resolution imaging tools have been in development for more than two decades; one that has garnered considerable interest in recent years is optical coherence tomography enhanced with adaptive optics. State-of-the-art adaptive optics optical coherence tomography (AO-OCT) makes it possible to visualize even highly transparent cells and measure some of their internal processes at all depths within the retina, permitting reconstruction of a 3D view of the living microscopic retina. In this review, we report current AO-OCT performance and its success in visualizing and quantifying these once-invisible cells in human eyes.
Topics: Humans; Ophthalmoscopy; Retina; Tomography, Optical Coherence
PubMed: 32609578
DOI: 10.1146/annurev-vision-030320-041255