1
|
Swanson WH, King BJ, Alluwimi MS, Malik R. Predicting perimetric defects from en face maps of retinal nerve fibre layer reflectance. Ophthalmic Physiol Opt 2024; 44:613-625. [PMID: 38404167 PMCID: PMC10999345 DOI: 10.1111/opo.13289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/27/2024]
Abstract
PURPOSE To develop criteria to predict visual hemifields with deep perimetric defects based on retinal nerve fibre layer (RNFL) reflectance, in a transparent process whose components can be assessed by independent laboratories analysing data from their own small groups. METHODS The analysis was carried out in four stages, using three independent groups of patients-30, 33 and 62 participants-with glaucoma and age-similar controls. The first stage used Group 1 to develop a criterion for RNFL reflectance images at 24, 36 or 48 μm below the inner limiting membrane (ILM). The second stage evaluated the criterion using Group 2. The third stage developed a second criterion to improve performance for Groups 1 and 2 combined. The fourth stage evaluated the second criterion with Group 3. Confidence intervals for sensitivity and specificity were then computed by combining results from all three groups. RESULTS The first criterion identified all hemifields with deep defects and no hemifields from controls, using a within-eye reference for healthy RNFL. For Group 2, specificity remained high but sensitivity was reduced. The second criterion improved sensitivity by using location-specific reference values. For Group 3, sensitivity remained high but reduced specificity was found. Confidence intervals showed substantial overlap for the two criteria. CONCLUSIONS We developed two criteria to identify patients with deep perimetric defects with high specificity and sensitivity. Several improvements are warranted: automated identification of the fovea-disc angle and optic disc locations, evaluation of normal variation in patterns of RNFL thickness, improved segmentation of ILM and major vasculature, reduction of within-eye variability in RNFL reflectance of healthy eyes, assessment of effects of image quality, assessment of effects of comorbidity and effectiveness of other devices.
Collapse
Affiliation(s)
| | - Brett J King
- Indiana University School of Optometry, Bloomington, Indiana, USA
| | - Muhammed S Alluwimi
- Department of Optometry, College of Applied Medical Sciences, Qassim University, Buraidah, Saudi Arabia
| | - Rizwan Malik
- Department of Surgery, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| |
Collapse
|
2
|
Boodram V, Lim H. Protective effects of nicotinamide in a mouse model of glaucoma DBA/2 studied by second-harmonic generation microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.07.583928. [PMID: 38496666 PMCID: PMC10942456 DOI: 10.1101/2024.03.07.583928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Glaucoma is a blinding disease where the retinal ganglion cells and their axons degenerate. Degradation of axonal microtubules is thought to play a critical role in the pathogenesis, but the mechanism is unknown. Here we investigate whether microtubule disruption in glaucoma can be alleviated by metabolic rescue. The morphology and integrity of microtubules of the retinal nerve fibers were evaluated by second-harmonic generation microscopy in a mouse model of glaucoma, DBA/2, which received a dietary supplement of nicotinamide to reduce metabolic stress. It was compared with control DBA/2, which did not receive nicotinamide, and non-glaucomatous DBA/2-Gpnmb+. We found that morphology but not microtubules are significantly protected by nicotinamide. Furthermore, from co-registered images of second-harmonic generation and immunofluorescence, it was determined that microtubule deficit was not due to a shortage of tubulins. Microtubule deficit colocalized with the sectors in which the retinal ganglion cells were disconnected from the brain, indicating that microtubule disruption is associated with axonal transport deficit in glaucoma. Together, our data suggests significant role axonal microtubules play in glaucomatous degeneration, offering a new opportunity for neuroprotection.
Collapse
Affiliation(s)
- Vinessia Boodram
- Department of Physics and Astronomy, Hunter College of the City University of New York, New York, NY 10065
| | - Hyungsik Lim
- Department of Physics and Astronomy, Hunter College of the City University of New York, New York, NY 10065
- School of Optometry, Indiana University, Bloomington, IN 47405
| |
Collapse
|
3
|
Lommatzsch C, van Oterendorp C. Current Status and Future Perspectives of Optic Nerve Imaging in Glaucoma. J Clin Med 2024; 13:1966. [PMID: 38610731 PMCID: PMC11012267 DOI: 10.3390/jcm13071966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/16/2024] [Accepted: 03/20/2024] [Indexed: 04/14/2024] Open
Abstract
Being the primary site of degeneration, the optic nerve has always been the focus of structural glaucoma assessment. The technical advancements, mainly of optical coherence tomography (OCT), now allow for a very precise quantification of the optic nerve head and peripapillary retina morphology. By far the most commonly used structural optic nerve parameter is the thickness of the parapapillary retinal nerve fiber, which has great clinical utility but also suffers from significant limitations, mainly in advanced glaucoma. Emerging novel imaging technologies, such as OCT angiography, polarization-sensitive or visible-light OCT and adaptive optics, offer new biomarkers that have the potential to significantly improve structural glaucoma diagnostics. Another great potential lies in the processing of the data already available. Artificial intelligence does not only help increase the reliability of current biomarkers but can also integrate data from various imaging modalities and other clinical measures to increase diagnostic accuracy. And it can, in a more efficient way, draw information from available datasets, such as an OCT scan, compared to the current concept of biomarkers, which only use a fraction of the whole dataset.
Collapse
Affiliation(s)
- Claudia Lommatzsch
- Department of Ophthalmology, St. Franziskus Hospital, Hohenzollernring 74, 48145 Muenster, Germany
- Department of Ophthalmology, University of Luebeck, 23562 Luebeck, Germany
| | | |
Collapse
|
4
|
Kurokawa K, Nemeth M. Multifunctional adaptive optics optical coherence tomography allows cellular scale reflectometry, polarimetry, and angiography in the living human eye. BIOMEDICAL OPTICS EXPRESS 2024; 15:1331-1354. [PMID: 38404344 PMCID: PMC10890865 DOI: 10.1364/boe.505395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/27/2024]
Abstract
Clinicians are unable to detect glaucoma until substantial loss or dysfunction of retinal ganglion cells occurs. To this end, novel measures are needed. We have developed an optical imaging solution based on adaptive optics optical coherence tomography (AO-OCT) to discern key clinical features of glaucoma and other neurodegenerative diseases at the cellular scale in the living eye. Here, we test the feasibility of measuring AO-OCT-based reflectance, retardance, optic axis orientation, and angiogram at specifically targeted locations in the living human retina and optic nerve head. Multifunctional imaging, combined with focus stacking and global image registration algorithms, allows us to visualize cellular details of retinal nerve fiber bundles, ganglion cell layer somas, glial septa, superior vascular complex capillaries, and connective tissues. These are key histologic features of neurodegenerative diseases, including glaucoma, that are now measurable in vivo with excellent repeatability and reproducibility. Incorporating this noninvasive cellular-scale imaging with objective measurements will significantly enhance existing clinical assessments, which is pivotal in facilitating the early detection of eye disease and understanding the mechanisms of neurodegeneration.
Collapse
Affiliation(s)
- Kazuhiro Kurokawa
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Morgan Nemeth
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| |
Collapse
|
5
|
Dunn M, Cull G, Reynaud J, Jennings D, Holthausen T, Di Polo A, Fortune B. Utility of Light-Adapted Full-Field Electroretinogram ON and OFF Responses for Detecting Glaucomatous Functional Damage. Transl Vis Sci Technol 2023; 12:16. [PMID: 37594448 PMCID: PMC10445177 DOI: 10.1167/tvst.12.8.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 07/13/2023] [Indexed: 08/19/2023] Open
Abstract
Purpose To compare parameters of electroretinogram (ERG) responses for their ability to detect functional loss in early stages of nonhuman primate (NHP) experimental glaucoma (EG), including photopic negative responses (PhNR) to a standard brief red flash on a blue background (R/B) and 200-ms-long R/B and white-on-white (W/W) flashes, to W/W flicker stimuli (5-50 Hz), and to a dark-adapted intensity series. Methods Light-adapted ERGs were recorded in 12 anesthetized monkeys with unilateral EG. Amplitudes and implicit times of the a-wave, b-wave, and d-wave were measured, as well as amplitudes of PhNRs and oscillatory potentials for flash onset and offset. Flicker ERGs were measured using peak-trough and fundamental frequency analyses. Dark-adapted ERG parameters were modeled by Naka-Rushton relationships. Results Only PhNR amplitudes were significantly reduced in EG eyes compared to fellow control (FC) eyes. The d-wave implicit time was delayed in EG versus FC eyes only for the W/W long flash, but in all eyes it was 10 to 20 ms slower for R/B versus the W/W condition. Flicker ERGs were <0.5 ms delayed in EG versus FC overall, but amplitudes were affected only at 5 Hz. The brief R/B PhNR amplitude had the highest sensitivity to detect EG and strongest correlation to parameters of structural damage. Conclusions The PhNR to the standard brief R/B stimulus was best for detecting and following early-stage functional loss in NHP EG. Translational Relevance These results suggest that there would be no benefit in using longer duration flashes to separate onset and offset responses for clinical management of glaucoma.
Collapse
Affiliation(s)
- Michaela Dunn
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Grant Cull
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Juan Reynaud
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Dawn Jennings
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Trinity Holthausen
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Adriana Di Polo
- Department of Neuroscience, Université de Montréal, Montréal, QC, Canada
- Neuroscience Division, Centre de Recherche du Centre Hospitalier, Université de Montréal, Montréal, QC, Canada
| | - Brad Fortune
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| |
Collapse
|
6
|
Hirasawa K, Yamaguchi J, Nagano K, Kanno J, Kasahara M, Shoji N. Degree of loss in the tissue thickness, microvascular density, specific perimetry and standard perimetry in early glaucoma. BMJ Open Ophthalmol 2023. [DOI: 10.1136/bmjophth-2023-001256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
ObjectiveTo identify the degree of loss of the circumpapillary retinal nerve fibre layer (cpRNFL), the layer from the macular RNFL to the inner plexiform layer (mGCL++), circumpapillary (cpVD) and macular vascular density (mVD), Pulsar perimetry and standard perimetry in early glaucoma.MethodsIn this cross-sectional study, one eye from each of 96 healthy controls and 90 eyes with open-angle glaucoma were measured with cpRNFL, mGCL++, cpVD, mVD, Pulsar perimetry with Octopus P32 test (Pulsar) and standard perimetry with Humphrey field analyser 24-2 test (HFA). For direct comparison, all parameters were converted to relative change values adjusted in both their dynamic range and age-corrected normal value.ResultsThe degree of loss in mGCL++ (−24.7%) and cpRNFL (−25.8%) was greater than that in mVD (−17.3%), cpVD (−14.9%), Pulsar (−10.1%) and HFA (−5.9%) (each p<0.01); the degree of loss in mVD and cpVD was greater than that in Pulsar and HFA (each p<0.01); and the degree of loss in Pulsar was greater than that in HFA (p<0.01). The discrimination ability between glaucomatous and healthy eyes (area under the curve) was higher for mGCL++ (0.90) and cpRNFL (0.93) than for mVD (0.78), cpVD (0.78), Pulsar (0.78) and HFA (0.79).ConclusionThe degree of loss of cpRNFL and mGCL++ thickness preceded by approximately 7%–10% and 15%–20% compared with the micro-VD and visual fields in early glaucoma, respectively.Trial registration numberUMIN Clinical Trials Registry (http://www.umin.ac.jp/; R000046076 UMIN000040372).
Collapse
|
7
|
Yin GS, van der Heide F, Littlejohns TJ, Kuźma E, Hayat S, Brayne C, Foster PJ, Luben R, Khawaja AP. Association Between Retinal Nerve Fiber Layer Thickness and Incident Dementia in the European Prospective Investigation into Cancer in Norfolk Cohort. J Alzheimers Dis 2023; 95:691-702. [PMID: 37574729 DOI: 10.3233/jad-230073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
BACKGROUND Retinal nerve fiber layer (RNFL) thickness may reflect cerebral status. OBJECTIVE This study assessed the relationship between RNFL thickness and incident all-cause dementia in the European Prospective Investigation into Cancer in Norfolk (EPIC-Norfolk) Eye Study. METHODS Glaucoma detection with variable corneal compensation (GDx-VCC) and Heidelberg Retinal Tomograph II (HRT II) derived global mean RNFL thickness from dementia-free participants at baseline within the EPIC-Norfolk Eye Study were analyzed. Incident dementia was identified through linkage to electronic medical records. Cox proportional hazard mixed-effects regression models adjusted for key confounders were used to examine the associations between RNFL thickness and incident dementia in four separate models. RESULTS 6,239 participants were included with 322 cases of incident dementia and mean age of 67.5-years old, with 49.7% women (median follow-up 13.2-years, interquartile range (11.7 to 14.6 years). Greater RNFL thickness (GDx-VCC) was not significantly associated with a lower risk of incident dementia in the full adjusted model [HR per quartile increase 0.95; 95% CI 0.82-1.10]. Similarly, RNFL thickness assessed with HRT II was also not associated with incident dementia in any model (full adjusted model; HR per quartile increase: 1.06; [95% CI 0.93-1.19]. Gender did not modify any associations under study. CONCLUSION GDx-VCC and HRT II derived RNFL thickness are unlikely to be useful predictors of incident dementia. Higher resolution optical imaging technologies may clarify whether there are useful relationships between neuro-retinal morphology and brain measures.
Collapse
Affiliation(s)
- Grace S Yin
- Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge School of Clinical Medicine, Cambridge, UK
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - Frank van der Heide
- Cardiovascular Research Institute Maastricht School for Cardiovascular Diseases, Maastricht University, the Netherlands
- Department of Internal Medicine, Maastricht University Medical Center, the Netherlands
| | | | - Elżbieta Kuźma
- Albertinen-Haus Centre for Geriatrics and Gerontology, University of Hamburg, Hamburg, Germany
| | - Shabina Hayat
- Department of Behavioural Science and Health, Institute of Epidemiology and Health Care, University College London, England, UK
| | - Carol Brayne
- Cambridge Public Health, University of Cambridge, Cambridge, UK
| | - Paul J Foster
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK
| | - Robert Luben
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK
| | - Anthony P Khawaja
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK
| |
Collapse
|
8
|
Cheloni R, Denniss J. Concordance of Objectively Detected Retinal Nerve Fiber Bundle Defects in En Face OCT Images with Conventional Structural and Functional Changes in Glaucoma. Ophthalmol Glaucoma 2023; 6:78-92. [PMID: 35835434 DOI: 10.1016/j.ogla.2022.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 06/24/2022] [Accepted: 07/05/2022] [Indexed: 01/25/2023]
Abstract
PURPOSE To assess how objectively detected defects in retinal nerve fiber bundle (RNFB) reflectance on en face OCT images relate to circumpapillary retinal nerve fiber layer thickness (cpRNFLT) and visual field defects. DESIGN Cross-sectional study. PARTICIPANTS Sixteen participants with early glaucoma and 29 age-matched healthy controls, of whom 22 had usable en face images for the establishment of normative levels of RNFB reflectance. METHODS All the participants underwent cpRNFLT scans, visual field examination, and wide-field OCT. En face reflectivity was assessed objectively using the Summary of Multiple Anatomically Adjusted Slabs method. En face defects were deemed concordant with cpRNFLT when they had at least 1 cpRNFLT point with P < 0.01, within ± 15° of the predicted insertion on the optic disc. Visual fields were examined using custom suprathreshold perimetry and SITA Standard 24-2. For each visual field location, the corresponding reflectance was deemed abnormal if any en face superpixel within ± 1° was abnormal. The overall, positive, and negative agreements were measured in each participant. MAIN OUTCOME MEASURES Proportion of concordant defects between en face reflectance analysis and cpRNFLT (%) as well as overall, positive, and negative agreements between en face reflectance analysis and visual field results. RESULTS Most en face abnormalities had concordant cpRNFLT defects in the mapped sector (median proportion concordant, 0.85; interquartile range, 0.74-0.95). In eyes with glaucoma, a median of 8.1% (range, 2.4%-23.7%) and 14.9% (range, 3.5%-29.1%) locations showed corresponding en face and visual field defects using 24-2 and custom perimetry, respectively. Both the perimetric strategies had moderate-to-good raw agreement with en face analysis (0.66-0.68), with stronger agreement on normal findings than on defects (0.77-0.78 and 0.4-0.44). CONCLUSIONS Objectively extracted reflectance defects showed strong concordance with conventional cpRNFLT damage and good agreement with perimetry, which could be enhanced by further minimization of image artifacts.
Collapse
Affiliation(s)
- Riccardo Cheloni
- School of Optometry and Vision Science, University of Bradford, United Kingdom
| | - Jonathan Denniss
- School of Optometry and Vision Science, University of Bradford, United Kingdom.
| |
Collapse
|
9
|
Steiner S, Schwarzhans F, Desissaire S, Resch H, Fischer G, Pircher M, Hitzenberger CK, Vass C. Birefringent Properties of the Peripapillary Retinal Nerve Fiber Layer in Healthy and Glaucoma Subjects Analyzed by Polarization-Sensitive OCT. Invest Ophthalmol Vis Sci 2022; 63:8. [DOI: 10.1167/iovs.63.12.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Stefan Steiner
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria
| | - Florian Schwarzhans
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Hemma Resch
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria
| | - Georg Fischer
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
10
|
Cheung H, Swanson WH, King BJ. Within-eye and between-subject variability for reflectance of the retinal nerve fibre layer. Ophthalmic Physiol Opt 2022; 42:1316-1325. [PMID: 35915921 PMCID: PMC9547838 DOI: 10.1111/opo.13027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 01/05/2023]
Abstract
PURPOSE Reflectance of retinal nerve fibre layer (RNFL) can contribute to detecting the presence of glaucomatous damage and defining its extent. As a step towards developing a normative database for RNFL reflectance, we assessed within-eye and between-subject variability for RNFL reflectance in healthy eyes. METHODS Vertical 30° × 15° volume scans at the optic disc were gathered using SD-OCT (Spectralis OCT) from people free of eye disease. Scans were gathered for both eyes of 30 younger adults (mean ± SD = 27 ± 3 years) and for one eye of 30 older adults (68 ± 8 years). Reflectance was quantified for each voxel as the depth-resolved attenuation coefficient (AC). Values for AC were extracted for four slabs (0-52, 24-52, 24-36 and 36-60 μm) and at depths from 24 to 60 μm below the inner limiting membrane (ILM) in 4 μm steps. RESULTS Between-subject and within-eye standard deviations (SDs) for the logarithm of AC were similar; median differences were 0.02-0.03 log unit across all four slabs and depths from 24 to 48 μm. Means for the logarithm of AC were higher for younger than older eyes by ~0.1 log unit; this age effect was not due to differences in the raw reflectance of the RNFL, but rather to age-related changes in reflectance of deeper retina affecting the calculation of AC. CONCLUSIONS In both groups, within-eye variability in RNFL reflectance near the optic disc was similar to between-subject variability. A better understanding of within-eye variability would be useful for developing normative databases.
Collapse
Affiliation(s)
- Hin Cheung
- Indiana University School of OptometryBloomingtonIndianaUSA
| | | | - Brett J. King
- Indiana University School of OptometryBloomingtonIndianaUSA
| |
Collapse
|
11
|
A high-accuracy and high-efficiency digital volume correlation method to characterize in-vivo optic nerve head biomechanics from optical coherence tomography. Acta Biomater 2022; 143:72-86. [PMID: 35196556 PMCID: PMC9035111 DOI: 10.1016/j.actbio.2022.02.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 01/30/2022] [Accepted: 02/16/2022] [Indexed: 11/20/2022]
Abstract
In-vivo optic nerve head (ONH) biomechanics characterization is emerging as a promising way to study eye physiology and pathology. We propose a high-accuracy and high-efficiency digital volume correlation (DVC) method to characterize the in-vivo ONH deformation from optical coherence tomography (OCT) volumes. Using a combination of synthetic tests and analysis of OCTs from monkey ONHs subjected to acutely elevated intraocular pressure, we demonstrate that our proposed methodology overcame several challenges for conventional DVC methods: First, a pre-registration technique was used to remove large ONH rigid body motion in OCT volumes which could lead to analysis failure; second, a modified 3D inverse-compositional Gaussian Newton method was used to ensure sub-voxel accuracy of displacement calculations despite high noise and low image contrast of some OCT volumes; third, a tricubic B-spline interpolation method was applied to improve computational efficiency; fourth, a confidence parameter was introduced to guide the searching path in the displacement calculation; fifth, a confidence-weighted strain calculation method was applied to further improve the accuracy. The proposed DVC method had displacement errors smaller than 0.037 and 0.028 voxels with Gaussian and speckle noises, respectively. The strain errors in the three directions were less than 0.0045 and 0.0018 with Gaussian and speckle noises, respectively. Compared with the conventional DVC method, the proposed method reduced the errors of displacement and strain calculations by up to 70% under large body motions, with 75% lower computation time, while saving about 30% memory. Our study demonstrates the potential of the proposed technique to investigate ONH biomechanics. STATEMENT OF SIGNIFICANCE: The biomechanics of the optic nerve head (ONH) in the posterior pole of the globe play a central role in eye physiology and pathology. The application of digital volume correlation (DVC) to the analysis of optical coherence tomography (OCT) images of the ONH has emerged as a promising way to quantify ONH biomechanics. Conventional DVC methods, however, face several important challenges when analyzing OCT images of the ONH. We introduce a high-accuracy and high-efficiency DVC method to characterize in vivo ONH deformations from OCT volumes. We demonstrate the new method using synthetic tests and actual OCT data from monkey ONHs. The new method also has the potential to be used to study other tissues, as OCT applications continue to expand.
Collapse
|
12
|
Yuhas PT, Ciamacca ML, Ramsey KA, Mayne DM, Stern-Green EA, Ohr M, Zimmerman A, Hartwick ATE, VanNasdale DA. Foveal Phase Retardation Correlates With Optically Measured Henle Fiber Layer Thickness. Front Med (Lausanne) 2022; 9:846738. [PMID: 35492328 PMCID: PMC9051020 DOI: 10.3389/fmed.2022.846738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 03/23/2022] [Indexed: 01/21/2023] Open
Abstract
This study quantified and compared phase retardation distribution in the central macula with the thickness of the Henle fiber layer (HFL). A scanning laser polarimeter (SLP) was used to acquire 20° × 40° macular-centered images, either with fixed corneal compensation or with variable corneal compensation, in two cohorts of clinically normal subjects (N = 36). Phase retardation maps from SLP imaging were used to generate a macular cross pattern (fixed compensation) or an annulus pattern (variable compensation) centered on the macula. Intensity profiles in the phase retardation maps were produced using annular regions of interest at eccentricities from 0.25° to 3°. Pixel intensity was averaged at each eccentricity, acting as a surrogate for macular phase retardation. Directional OCT images were acquired in the horizontal and vertical meridians in all subjects, allowing visualization of the HFL thickness. HFL thickness was manually segmented in each meridian and averaged. In both cohorts, phase retardation and HFL thickness were highly correlated in the central 3° assessed, providing further evidence that the source of the phase retardation signal in the central macula is dominated by the HFL and that the center of the macula on cross sectional imaging corresponds closely with the center of the macular cross on SLP imaging.
Collapse
Affiliation(s)
- Phillip T. Yuhas
- College of Optometry, The Ohio State University, Columbus, OH, United States,*Correspondence: Phillip T. Yuhas
| | - Marisa L. Ciamacca
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | - Keith A. Ramsey
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | - Danielle M. Mayne
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | | | - Matthew Ohr
- Department of Ophthalmology and Visual Sciences, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Aaron Zimmerman
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | | | - Dean A. VanNasdale
- College of Optometry, The Ohio State University, Columbus, OH, United States
| |
Collapse
|
13
|
Musial G, Adhikari S, Mirhajianmoghadam H, Queener HM, Schill AW, Patel NB, Porter J. Longitudinal In Vivo Changes in Radial Peripapillary Capillaries and Optic Nerve Head Structure in Non-Human Primates With Early Experimental Glaucoma. Invest Ophthalmol Vis Sci 2022; 63:10. [PMID: 34994770 PMCID: PMC8742514 DOI: 10.1167/iovs.63.1.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose There is conflicting evidence regarding whether a loss of radial peripapillary capillaries (RPCs) precedes neuronal loss in glaucoma. We examined the time course of in vivo changes in RPCs, optic nerve head (ONH) structure, and retinal nerve fiber layer thickness (RNFLT) in experimental glaucoma (EG). Methods Spectral domain optical coherence tomography images were acquired before and approximately every two weeks after inducing unilateral EG in nine rhesus monkeys to quantify mean anterior lamina cribrosa surface depth (ALCSD), minimum rim width (MRW), and RNFLT. Perfused RPC density was measured from adaptive optics scanning laser ophthalmoscope images acquired on the temporal half of the ONH. The time of first significant change was quantified as when values fell and remained outside of the 95% confidence interval established from control eyes. Results Mean ALCSD and/or MRW were the first parameters to change in eight EG eyes. RPC density changed first in the ninth. At their first points of change, mean ALCSD posteriorly deformed by 100.2 ± 101.2 µm, MRW thinned by 82.3 ± 65.9 µm, RNFLT decreased by 25 ± 14 µm, and RPC density decreased by 4.5 ± 2.1%. RPC density decreased before RNFL thinning in 5 EG eyes. RNFLT decreased before RPC density decreased in two EG eyes, whereas two EG eyes had simultaneous changes. Conclusions In most EG eyes, RPC density decreased before (or simultaneous with) a change in RNFLT, suggesting that vascular factors may play a role in axonal loss in some eyes in early glaucoma.
Collapse
Affiliation(s)
- Gwen Musial
- University of Houston, Houston, Texas, United States
| | | | | | | | | | | | - Jason Porter
- University of Houston, Houston, Texas, United States
| |
Collapse
|
14
|
Jasien JV, Read AT, van Batenburg-Sherwood J, Perkumas KM, Ethier CR, Stamer WD, Samuels BC. Anterior Segment Anatomy and Conventional Outflow Physiology of the Tree Shrew (Tupaia belangeri). Invest Ophthalmol Vis Sci 2022; 63:21. [PMID: 35040876 PMCID: PMC8764208 DOI: 10.1167/iovs.63.1.21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 10/26/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose Rodent and primate models are commonly used in glaucoma research; however, both have their limitations. The tree shrew (Tupaia belangeri) is an emerging animal model for glaucoma research owing in part to having a human-like optic nerve head anatomy, specifically a collagenous load-bearing lamina. However, the anterior segment anatomy and function have not been extensively studied in the tree shrew. Thus, the purpose of this study was to provide the first detailed examination of the anterior segment anatomy and aqueous outflow facility in the tree shrew. Methods Aqueous outflow dynamics were measured in five ostensibly normal eyes from three tree shrews using the iPerfusion system over a range of pressures. Gross histological assessment and immunohistochemistry were performed to characterize anterior segment anatomy and to localize several key molecules related to aqueous outflow. Results Anterior segment anatomy in tree shrews is similar to humans, demonstrating a scleral spur, a multilayered trabecular meshwork and a circular Schlemm's canal with a single lumen. Average outflow facility was 0.193 µL/min/mm Hg (95% confidence interval, 0.153-0.244), and was stable over time. Outflow facility was more similar between contralateral eyes (approximately 5% average difference) than between eyes of different animals. No significant dependence of outflow facility on time or pressure was detected (pressure-flow nonlinearity parameter of 0.01 (95% % confidence interval, -0.29 to 0.31 CI µL/min/mm Hg). Conclusions These studies lend support to the usefulness of the tree shrew as a novel animal model in anterior segment glaucoma and pharmacology research. The tree shrew's cost, load-bearing collagenous lamina cribrosa, and lack of washout or anterior chamber deepening provides a distinct experimental and anatomic advantage over the current rodent and nonhuman primate models used for translational research.
Collapse
Affiliation(s)
- Jessica V. Jasien
- Vision Science Graduate Program, School of Optometry, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - A. Thomas Read
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States
| | | | - Kristin M. Perkumas
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States
| | - C. Ross Ethier
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States
| | - W. Daniel Stamer
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States
| | - Brian C. Samuels
- Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| |
Collapse
|
15
|
Schwarzhans F, Desissaire S, Steiner S, Pircher M, Hitzenberger CK, Resch H, Vass C, Fischer G. Automatic retinal nerve fiber bundle tracing based on large field of view polarization sensitive OCT data. BIOMEDICAL OPTICS EXPRESS 2022; 13:65-81. [PMID: 35154854 PMCID: PMC8803019 DOI: 10.1364/boe.443958] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/19/2021] [Accepted: 11/21/2021] [Indexed: 06/14/2023]
Abstract
A technique to accurately estimate trajectories of retinal nerve fiber bundles (RNFB) in a large field of view (FOV) image covering 45° is described. The method utilizes stitched projections of polarization-sensitive optical coherence tomography (PS-OCT) data, as well as a mathematical model of average RNFB trajectories as prior. The fully automatic process was applied to data recorded in healthy subjects and glaucoma patients and automatically detected individual RNFB trajectories are compared to manual traces.
Collapse
Affiliation(s)
- Florian Schwarzhans
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, 1090, Austria
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University Vienna, Vienna, 1090, Austria
| | - Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, 1090, Austria
| | - Stefan Steiner
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, 1090, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, 1090, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, 1090, Austria
| | - Hemma Resch
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, 1090, Austria
| | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, 1090, Austria
| | - Georg Fischer
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University Vienna, Vienna, 1090, Austria
| |
Collapse
|
16
|
Cheloni R, Dewsbery SD, Denniss J. Enhanced Objective Detection of Retinal Nerve Fiber Bundle Defects in Glaucoma With a Novel Method for En Face OCT Slab Image Construction and Analysis. Transl Vis Sci Technol 2021; 10:1. [PMID: 34605878 PMCID: PMC8496419 DOI: 10.1167/tvst.10.12.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/01/2021] [Indexed: 02/07/2023] Open
Abstract
Purpose To introduce and evaluate the performance in detecting glaucomatous abnormalities of a novel method for extracting en face slab images (SMAS), which considers varying individual anatomy and configuration of retinal nerve fiber bundles. Methods Dense central retinal spectral domain optical coherence tomography scans were acquired in 16 participants with glaucoma and 19 age-similar controls. Slab images were generated by averaging reflectivity over different depths below the inner limiting membrane according to several methods. SMAS considered multiple 16 µm thick slabs from 8 to 116 µm below the inner limiting membrane, whereas 5 alternative methods considered single summary slabs of various thicknesses and depths. Superpixels in eyes with glaucoma were considered abnormal if below the first percentile of distributions fitted to control data for each method. The ability to detect glaucoma defects was measured by the proportion of abnormal superpixels. Proportion of superpixels below the fitted first percentile in controls was used as a surrogate false-positive rate. The effects of slab methods on performance measures were evaluated with linear mixed models. Results The ability to detect glaucoma defects varied between slab methods, χ2(5) = 120.9, P < 0.0001, with SMAS showing proportion of abnormal superpixels 0.05 to 0.09 greater than alternatives (all P < 0.0001). No slab method found abnormal superpixels in controls. Conclusions SMAS outperformed alternatives in detecting abnormalities in eyes with glaucoma. SMAS evaluates all depths with potential retinal nerve fiber bundle presence by combining multiple slabs, resulting in greater detection of reflectance abnormalities with no increase in surrogate false positives. Translational Relevance SMAS may be used to objectively detect glaucoma defects in en face optical coherence tomography images.
Collapse
Affiliation(s)
- Riccardo Cheloni
- School of Optometry and Vision Science, University of Bradford, Bradford, UK
| | - Simon D. Dewsbery
- Department of Ophthalmology, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jonathan Denniss
- School of Optometry and Vision Science, University of Bradford, Bradford, UK
| |
Collapse
|
17
|
Tan O, Liu L, You Q, Wang J, Chen A, Ing E, Morrison JC, Jia Y, Huang D. Focal Loss Analysis of Nerve Fiber Layer Reflectance for Glaucoma Diagnosis. Transl Vis Sci Technol 2021; 10:9. [PMID: 34111254 PMCID: PMC8107497 DOI: 10.1167/tvst.10.6.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate nerve fiber layer (NFL) reflectance for glaucoma diagnosis. Methods Participants were imaged with 4.5 × 4.5 mm volumetric disc scans using spectral-domain optical coherence tomography. The normalized NFL reflectance map was processed by an azimuthal filter to reduce directional reflectance bias caused by variation of beam incidence angle. The peripapillary area of the map was divided into 160 superpixels. Average reflectance was the mean of superpixel reflectance. Low-reflectance superpixels were identified as those with NFL reflectance below the fifth percentile normative cutoff. Focal reflectance loss was measured by summing loss in low-reflectance superpixels. Results Thirty-five normal, 30 preperimetric, and 35 perimetric glaucoma participants were enrolled. Azimuthal filtering improved the repeatability of the normalized NFL reflectance, as measured by the pooled superpixel standard deviation (SD), from 0.73 to 0.57 dB (P < 0.001, paired t-test) and reduced the population SD from 2.14 to 1.78 dB (P < 0.001, t-test). Most glaucomatous reflectance maps showed characteristic patterns of contiguous wedge or diffuse defects. Focal NFL reflectance loss had significantly higher diagnostic sensitivity than the best NFL thickness parameter (from map or profile): 77% versus 55% (P < 0.001) in glaucoma eyes with the specificity fixed at 99%. Conclusions Azimuthal filtering reduces the variability of NFL reflectance measurements. Focal NFL reflectance loss has excellent glaucoma diagnostic accuracy compared to the standard NFL thickness parameters. The reflectance map may be useful for localizing NFL defects. Translational Relevance The high diagnostic accuracy of NFL reflectance may make population-based screening feasible.
Collapse
Affiliation(s)
- Ou Tan
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Liang Liu
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Qisheng You
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Jie Wang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Aiyin Chen
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Eliesa Ing
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - John C Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Yali Jia
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - David Huang
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| |
Collapse
|
18
|
Cheloni R, Dewsbery SD, Denniss J. A Simple Subjective Evaluation of Enface OCT Reflectance Images Distinguishes Glaucoma From Healthy Eyes. Transl Vis Sci Technol 2021; 10:31. [PMID: 34036303 PMCID: PMC8161697 DOI: 10.1167/tvst.10.6.31] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/16/2021] [Indexed: 01/06/2023] Open
Abstract
Purpose We present a subjective approach to detecting glaucomatous defects in enface images and assess its diagnostic performance. We also test the hypothesis that if reflectivity changes precede thickness changes in glaucoma there should be reduced correlation between the modalities in glaucoma compared to controls. Methods Twenty glaucoma participants and 20 age-matched controls underwent high-resolution OCT scans of one eye. 4 µm-thick enface slabs were constructed through the retina. Enface indices were depths of first gap in visible retinal nerve fiber bundles (RNFBs) and last visible bundle, subjectively evaluated in six sectors of a 3.5 mm circle around the optic disc. Retinal nerve fiber layer thickness (RNFLT) along the same circle was extracted at angles corresponding to enface indices. Between-group differences were tested by linear mixed models. Diagnostic performance was measured by partial receiver operating characteristic area (pAUC). Results First gap and last visible bundle were closer to the inner limiting membrane in glaucoma eyes (both P < 0.0001). Enface indices showed excellent diagnostic performance (pAUCs 0.63-1.00), similar to RNFLT (pAUCs 0.63-0.95). Correlation between enface and RNFLT parameters was strong in healthy (r = 0.81-0.92) and glaucoma eyes (r = 0.73-0.80). Conclusions This simple subjective method reliably identifies glaucomatous defects in enface images with diagnostic performance at least as good as existing thickness indices. Thickness and reflectivity were similarly related in healthy and glaucoma eyes, providing no strong evidence of reflectivity loss preceding thinning. Objective analyses may realize further potential of enface OCT images in glaucoma. Translational Relevance Novel enface OCT indices may aid glaucoma diagnosis.
Collapse
Affiliation(s)
- Riccardo Cheloni
- School of Optometry and Vision Science, University of Bradford, UK
| | - Simon D. Dewsbery
- Ophthalmology Department, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jonathan Denniss
- School of Optometry and Vision Science, University of Bradford, UK
| |
Collapse
|
19
|
Pollreisz A, Desissaire S, Sedova A, Hajdu D, Datlinger F, Schwarzhans F, Steiner S, Steiner I, Vass C, Hitzenberger CK, Pircher M, Schmidt-Erfurth U. Early Identification of Retinal Neuropathy in Subclinical Diabetic Eyes by Reduced Birefringence of the Peripapillary Retinal Nerve Fiber Layer. Invest Ophthalmol Vis Sci 2021; 62:24. [PMID: 33871570 PMCID: PMC8083066 DOI: 10.1167/iovs.62.4.24] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose To study birefringence of the peripapillary retinal nerve fiber layer (RNFL) of diabetic eyes with no clinical signs of diabetic retinopathy (DR) or mild to moderate DR stages using spectral-domain polarization-sensitive (PS) optical coherence tomography (OCT). Methods In this observational pilot study, circular PS-OCT scans centered on the optic nerve head were recorded in prospectively recruited diabetic and age-matched healthy eyes. From averaged circumpapillary intensity and retardation tomograms plots of RNFL birefringence were obtained by a linear fit of retardation versus depth within the RNFL tissue for each A-scan position and mean birefringence values for RNFL calculated. Spectral-domain OCT imaging (Heidelberg Engineering) was performed to assess peripapillary RNFL thickness and macular ganglion cell complex (GCC). Results Out of 70 eyes of 43 diabetic patients (mean ± SD age: 50.86 ± 15.71) 36 showed no signs of DR, 17 mild and 17 moderate nonproliferative DR with no diabetic macular edema. Thirty-four eyes of 34 healthy subjects (53.21 ± 13.88 years) served as controls. Compared with healthy controls (0.143° ± 0.014°/µm) mean total birefringence of peripapillary RNFL was significantly reduced in subclinical diabetic eyes (0.131° ± 0.014°/µm; P = 0.0033), as well as in mild to moderate DR stages (0.125° ± 0.018°/µm, P < 0.0001) with borderline statistically significant differences between diabetic patients (P = 0.0049). Mean birefringence values were significantly lower in inferior compared with superior RNFL sectors (P < 0.0001) of diabetic eyes with no such difference detected in the healthy control group. Conclusions We identified evidence of early neuroretinal alteration in diabetic eyes through reduced peripapillary RNFL birefringence assessed by PS-OCT occurring before appearance of clinical microvascular lesions or GCC alterations.
Collapse
Affiliation(s)
- Andreas Pollreisz
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Aleksandra Sedova
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Dorottya Hajdu
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Felix Datlinger
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Florian Schwarzhans
- Center for Medical Statistics, Informatics and Intelligent Systems, Section for Medical Statistics, Medical University Vienna, Vienna, Austria
| | - Stefan Steiner
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Irene Steiner
- Center for Medical Statistics, Informatics and Intelligent Systems, Section for Medical Statistics, Medical University Vienna, Vienna, Austria
| | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Christoph K Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | | |
Collapse
|
20
|
Fuller-Carter PI, Basiri H, Harvey AR, Carvalho LS. Focused Update on AAV-Based Gene Therapy Clinical Trials for Inherited Retinal Degeneration. BioDrugs 2021; 34:763-781. [PMID: 33136237 DOI: 10.1007/s40259-020-00453-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Inherited retinal diseases (IRDs) comprise a clinically and genetically heterogeneous group of disorders that can ultimately result in photoreceptor dysfunction/death and vision loss. With over 270 genes known to be involved in IRDs, translation of treatment strategies into clinical applications has been historically difficult. However, in recent years there have been significant advances in basic research findings as well as translational studies, culminating in an increasing number of clinical trials with the ultimate goal of reducing vision loss and associated morbidities. The recent approval of Luxturna® (voretigene neparvovec-rzyl) for Leber congenital amaurosis type 2 (LCA2) prompts a review of the current clinical trials for IRDs, with a particular focus on the importance of adeno-associated virus (AAV)-based gene therapies. The present article reviews the current state of AAV use in gene therapy clinical trials for IRDs, with a brief background on AAV and the reasons behind its dominance in ocular gene therapy. It will also discuss pre-clinical progress in AAV-based therapies aimed at treating other ocular conditions that can have hereditable links, and what alternative technologies are progressing in the same therapeutic space.
Collapse
Affiliation(s)
- Paula I Fuller-Carter
- Centre for Ophthalmology and Visual Sciences (Incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Hamed Basiri
- Centre for Ophthalmology and Visual Sciences (Incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Alan R Harvey
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Perron Institute for Neurological and Translational Science, Nedlands, WA, Australia
| | - Livia S Carvalho
- Centre for Ophthalmology and Visual Sciences (Incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia.
| |
Collapse
|
21
|
Gilmore CS, Lim KO, Garvin MK, Wang JK, Ledolter J, Fenske AL, Gentz CL, Nellis J, Armstrong MT, Kardon RH. Association of Optical Coherence Tomography With Longitudinal Neurodegeneration in Veterans With Chronic Mild Traumatic Brain Injury. JAMA Netw Open 2020; 3:e2030824. [PMID: 33351088 PMCID: PMC7756235 DOI: 10.1001/jamanetworkopen.2020.30824] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
IMPORTANCE Mild traumatic brain injury (TBI) may predispose individuals to progressive neurodegeneration. OBJECTIVE To identify evidence of neurodegeneration through longitudinal evaluation of changes in retinal layer thickness using optical coherence tomography in veterans with a history of mild TBI. DESIGN, SETTING, AND PARTICIPANTS This longitudinal cohort study evaluated veterans who were receiving services at the Minneapolis Veterans Affairs Health Care System. Symptomatic or mild TBI was diagnosed according to the Mayo TBI Severity Classification System. Participants in the age-matched control group had no history of TBI. Participants with any history or evidence of retinal or optic nerve disease that could affect retinal thickness were excluded. Data analysis was performed from July 2019 to February 2020. EXPOSURES The presence and severity of mild TBI were determined through consensus review of self-report responses during the Minnesota Blast Exposure Screening Tool semistructured interview. MAIN OUTCOMES AND MEASURES Change over time of retinal nerve fiber layer (RNFL) thickness. RESULTS A total of 139 veterans (117 men [84%]; mean [SD] age, 49.9 [11.1] years) were included in the study, 69 in the TBI group and 70 in the control group. Veterans with mild TBI showed significantly greater RNFL thinning compared with controls (mean [SE] RNFL slope, -1.47 [0.24] μm/y vs -0.31 [0.32] μm/y; F1,122 = 8.42; P = .004; Cohen d = 0.52). Functionally, veterans with mild TBI showed greater declines in visual field mean deviation (mean [SE] slope, -0.09 [0.14] dB/y vs 0.46 [0.23] dB/y; F1,122 = 4.08; P = .046; Cohen d = 0.36) and pattern standard deviation (mean [SE] slope, 0.09 [0.06] dB/y vs -0.10 [0.07] dB/y; F1,122 = 4.78; P = .03; Cohen d = 0.39) and high spatial frequency (12 cycles/degree) contrast sensitivity compared with controls. Cognitively, there was a significantly greater decrease in the number of errors over time during the Groton Maze Learning Test (GMLT) in controls compared with veterans with mild TBI (mean [SE] slope, -9.30 [1.48] errors/y vs -5.23 [1.24] errors/y; F1,127 = 4.43; P = .04; Cohen d = 0.37). RNFL tissue loss was significantly correlated with both worsening performance on the GMLT over time (Spearman ρ = -0.20; P = .03) and mild TBI severity (Spearman ρ = -0.25; P = .006). The more severe the mild TBI (larger Minnesota Blast Exposure Screening Tool severity score), the faster the reduction in RNFL thickness (ie, the more negative the slope) across time. CONCLUSIONS AND RELEVANCE This cohort study found longitudinal evidence for significant, progressive neural degeneration over time in veterans with mild TBI, as indicated by greater RNFL tissue loss in patients with mild TBI vs controls, as well as measures of function. These results suggest that these longitudinal measures may be useful biomarkers of neurodegeneration. Changes in this biomarker may provide early detection of subsequent cognitive and functional deficits that may impact veterans' independence and need for care.
Collapse
Affiliation(s)
- Casey S. Gilmore
- Minneapolis VA Healthcare System, Minneapolis, Minnesota
- Defense and Veterans Brain Injury Center, Minneapolis, Minnesota
| | - Kelvin O. Lim
- Minneapolis VA Healthcare System, Minneapolis, Minnesota
- Defense and Veterans Brain Injury Center, Minneapolis, Minnesota
- Department of Psychiatry, University of Minnesota, Minneapolis
| | - Mona K. Garvin
- Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, Iowa
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City
| | - Jui-Kai Wang
- Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, Iowa
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City
| | - Johannes Ledolter
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City
- Department of Business Analytics and Department of Statistics and Actuarial Science, University of Iowa, Iowa City
| | - Alicia L. Fenske
- Minneapolis VA Healthcare System, Minneapolis, Minnesota
- Defense and Veterans Brain Injury Center, Minneapolis, Minnesota
| | - Carolyn L. Gentz
- Minneapolis VA Healthcare System, Minneapolis, Minnesota
- Defense and Veterans Brain Injury Center, Minneapolis, Minnesota
| | - Julie Nellis
- Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City
| | - Michael T. Armstrong
- Minneapolis VA Healthcare System, Minneapolis, Minnesota
- Defense and Veterans Brain Injury Center, Minneapolis, Minnesota
| | - Randy H. Kardon
- Center for the Prevention and Treatment of Visual Loss, Iowa City VA Healthcare System, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City
| |
Collapse
|
22
|
Desissaire S, Pollreisz A, Sedova A, Hajdu D, Datlinger F, Steiner S, Vass C, Schwarzhans F, Fischer G, Pircher M, Schmidt-Erfurth U, Hitzenberger CK. Analysis of retinal nerve fiber layer birefringence in patients with glaucoma and diabetic retinopathy by polarization sensitive OCT. BIOMEDICAL OPTICS EXPRESS 2020; 11:5488-5505. [PMID: 33149966 PMCID: PMC7587266 DOI: 10.1364/boe.402475] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
The retinal nerve fiber layer (RNFL) is a fibrous tissue that shows form birefringence. This optical tissue property is related to the microstructure of the nerve fiber axons that carry electrical signals from the retina to the brain. Ocular diseases that are known to cause neurologic changes, like glaucoma or diabetic retinopathy (DR), might alter the birefringence of the RNFL, which could be used for diagnostic purposes. In this pilot study, we used a state-of-the-art polarization sensitive optical coherence tomography (PS-OCT) system with an integrated retinal tracker to analyze the RNFL birefringence in patients with glaucoma, DR, and in age-matched healthy controls. We recorded 3D PS-OCT raster scans of the optic nerve head area and high-quality averaged circumpapillary PS-OCT scans, from which RNFL thickness, retardation and birefringence were derived. The precision of birefringence measurements was 0.005°/µm. As compared to healthy controls, glaucoma patients showed a slightly reduced birefringence (0.129 vs. 0.135°/µm), although not statistically significant. The DR patients, however, showed a stronger reduction of RNFL birefringence (0.103 vs. 0.135°/µm) which was highly significant. This result might open new avenues into early diagnosis of DR and related neurologic changes.
Collapse
Affiliation(s)
- Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, 1090, Austria
| | - Andreas Pollreisz
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Aleksandra Sedova
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Dorottya Hajdu
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Felix Datlinger
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Stefan Steiner
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Florian Schwarzhans
- Institute of Medical Information Management, Medical University of Vienna, Vienna, 1090, Austria
| | - Georg Fischer
- Institute of Medical Information Management, Medical University of Vienna, Vienna, 1090, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, 1090, Austria
| | - Ursula Schmidt-Erfurth
- Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, 1090, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, 1090, Austria
| |
Collapse
|
23
|
Chan ASY, Tun TA, Allen JC, Lynn MN, Tun SBB, Barathi VA, Girard MJA, Aung T, Aihara M. Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension. Sci Rep 2020; 10:14709. [PMID: 32895414 PMCID: PMC7477239 DOI: 10.1038/s41598-020-71555-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/19/2020] [Indexed: 11/16/2022] Open
Abstract
In humans, the longitudinal characterisation of early optic nerve head (ONH) damage in ocular hypertension (OHT) is difficult as patients with glaucoma usually have structural ONH damage at the time of diagnosis. Previous studies assessed glaucomatous ONH cupping by measuring the anterior lamina cribrosa depth (LCD) and minimal rim width (MRW) using optical coherence tomography (OCT). In this study, we induced OHT by repeated intracameral microbead injections in 16 cynomolgus primates (10 unilateral; 6 bilateral) and assessed the structural changes of the ONH longitudinally to observe early changes. Elevated intraocular pressure (IOP) in OHT eyes was maintained for 7 months and serial OCT measurements were performed during this period. The mean IOP was significantly elevated in OHT eyes when compared to baseline and compared to the control eyes. Thinner MRW and deeper LCD values from baseline were observed in OHT eyes with the greatest changes seen between month 1 and month 2 of OHT. Both the mean and maximum IOP values were significant predictors of MRW and LCD changes, although the maximum IOP was a slightly better predictor. We believe that this model could be useful to study IOP-induced early ONH structural damage which is important for understanding glaucoma pathogenesis.
Collapse
Affiliation(s)
- Anita S Y Chan
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore. .,Department of Ophthalmology, University of Tokyo, Tokyo, Japan.
| | - Tin Aung Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | | | - Myoe Naing Lynn
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Sai Bo Bo Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Veluchamy Amutha Barathi
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | - Tin Aung
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Makoto Aihara
- Department of Ophthalmology, University of Tokyo, Tokyo, Japan
| |
Collapse
|
24
|
Sakamoto M, Mori S, Ueda K, Kurimoto T, Kusuhara S, Yamada-Nakanishi Y, Nakamura M. En Face Slab Images Visualize Nerve Fibers With Residual Visual Sensitivity in Significantly Thinned Macular Areas of Advanced Glaucomatous Eyes. Invest Ophthalmol Vis Sci 2019; 60:2811-2821. [PMID: 31260033 DOI: 10.1167/iovs.18-25910] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The present study aimed to assess the ability of en face slab images of maculae to detect residual nerve fiber bundles in eyes with advanced glaucoma. Methods This study included 36 eyes with diffuse thinning of the ganglion cell and inner plexiform layers (GCL+IPL). Inclusion criterion was GCL+IPL thickness of <1% of the normative database level as detected using optical coherence tomography (OCT). En face slab images (50-μm thickness) were reconstructed from the macular cube scan data using advanced visualization settings. Thereafter, we assessed the agreement of the locations between hyperreflective nerve fiber bundles and normal points in the Humphrey visual field test 10-2 pattern deviation (PD) plots. Additionally, total deviation (TD) corresponding to hyperreflective and hyporeflective areas was compared. Results Hyperreflective areas were detected in 31 out of 36 eyes; all 31 eyes exhibited at least one normal PD point despite the substantial GCL+IPL thinning in the macular region. Two eyes with abnormalities in all PD points showed no hyperreflective area. The remaining three eyes had normal PD points despite the lack of high reflectivity areas in the slab images. Therefore, 91.7% of eyes showed agreement between en face slab images and PD plots. Moreover, hyperreflective areas demonstrated significantly better TD than hyporeflective areas. Conclusions En face slab images of maculae were able to reveal the residual nerve fiber bundles in the eyes with advanced glaucoma despite the GCL+IPL thickness in the maculae being diffusely and substantially reduced.
Collapse
Affiliation(s)
- Mari Sakamoto
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Sotaro Mori
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Kaori Ueda
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Takuji Kurimoto
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Sentaro Kusuhara
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Yuko Yamada-Nakanishi
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| | - Makoto Nakamura
- Kobe University Graduate School of Medicine, Department of Surgery, Division of Ophthalmology, Kobe, Japan
| |
Collapse
|
25
|
Sharoukhov D, Bucinca-Cupallari F, Lim H. Microtubule Imaging Reveals Cytoskeletal Deficit Predisposing the Retinal Ganglion Cell Axons to Atrophy in DBA/2J. Invest Ophthalmol Vis Sci 2019; 59:5292-5300. [PMID: 30383181 PMCID: PMC6218151 DOI: 10.1167/iovs.18-24150] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Glaucoma is characterized by progressive loss of the retinal ganglion cells (RGCs) and their axons. Here we test an outstanding notion that microtubules (MTs) within RGC axons degrade before the loss of morphology (“MT hypothesis”). Methods The integrity of axonal MTs was interrogated by intrinsic second-harmonic generation (SHG) microscopy. Using DBA/2J mice as a model of glaucoma and DBA/2J-Gpnmb+ as a nonglaucomatous control, the relationship between MT disruption and morphology was quantitatively examined as a function of age and sex in the fresh retinal wholemounts. Results The mean SHG density (i.e., the mean SHG intensity per thickness) was significantly lower in DBA/2J than in DBA/2J-Gpnmb+ and also depended on sex and age. The loss of SHG density, indicating MT disruption within intact RGC axons, occurred in a sectorial manner near the loss of the retinal nerve fiber bundles. The decay rate of SHG density was approximately 97% higher than that of thickness. Conclusions Collectively, the results indicate that the breakdown of MTs is pathology of glaucoma and likely a precursor of morphological atrophy. Based on a new finding that SHG density is highly variable and spatially discrete, a new model of RGC degeneration is proposed. This study validates SHG retinal imaging for elucidating the role and mechanism of MT deficiency in the course of glaucoma pathogenesis.
Collapse
Affiliation(s)
- Denis Sharoukhov
- Department of Physics and Astronomy, Hunter College and the Graduate Center of the City University of New York, New York, New York, United States
| | - Festa Bucinca-Cupallari
- Department of Physics and Astronomy, Hunter College and the Graduate Center of the City University of New York, New York, New York, United States
| | - Hyungsik Lim
- Department of Physics and Astronomy, Hunter College and the Graduate Center of the City University of New York, New York, New York, United States
| |
Collapse
|
26
|
Leitgeb RA. En face optical coherence tomography: a technology review [Invited]. BIOMEDICAL OPTICS EXPRESS 2019; 10:2177-2201. [PMID: 31143489 PMCID: PMC6524600 DOI: 10.1364/boe.10.002177] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/01/2019] [Accepted: 03/05/2019] [Indexed: 05/20/2023]
Abstract
A review on the technological development of en face optical coherence tomography (OCT) and optical coherence microscopy (OCM) is provided. The terminology originally referred to time domain OCT, where the preferential scanning was performed in the en face plane. Potentially the fastest realization of en face image recording is full-field OCT, where the full en face plane is illuminated and recorded simultaneously. The term has nowadays been adopted for high-speed Fourier domain approaches, where the en face image is reconstructed from full 3D volumes either by direct slicing or through axial projection in post processing. The success of modern en face OCT lies in its immediate and easy image interpretation, which is in particular of advantage for OCM or OCT angiography. Applications of en face OCT with a focus on ophthalmology are presented. The review concludes by outlining exciting technological prospects of en face OCT based both on time as well as on Fourier domain OCT.
Collapse
Affiliation(s)
- R A Leitgeb
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
- Christian Doppler Laboratory for Innovative Optical Imaging and its Translation to Medicine, Medical University Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| |
Collapse
|
27
|
Yan ZC, Yang XJ, Chen HR, Deng SF, Zhu YT, Zhuo YH. Effects of chronic elevated intraocular pressure on parameters of optical coherence tomography in rhesus monkeys. Int J Ophthalmol 2019; 12:542-548. [PMID: 31024804 DOI: 10.18240/ijo.2019.04.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 10/09/2018] [Indexed: 11/23/2022] Open
Abstract
AIM To determine the progression of parameters from optical coherence tomography (OCT) in chronic elevated intraocular pressure (IOP) monkeys. METHODS A chronic elevated IOP model of rhesus monkeys was induced by laser photocoagulation. Representative OCT parameters, including the average and four-quadrant retinal nerve fiber layer (RNFL) thickness, and parameters from optic nerve head (ONH) analysis were collected before and after laser treatments biweekly for up to 28wk. The performance of each parameter for early progression detection was analyzed. The progressive trends toward elevated IOP were analyzed using a linear mixed-effects model. RESULTS There were 10 successfully maintained high IOP eyes in 7 monkeys. The follow-up time was 24±5.37wk. With cumulative IOP elevation, the cup area, rim area and C/D area ratio were statistically significantly changed as early as 2wk after elevated IOP induction (P<0.05). The quadrant RNFL thickness changed at 6wk after high IOP induction, and the superior and inferior RNFL thicknesses exhibited more obvious reductions than other quadrants. The average RNFL thickness was the last one to show a significant decrease at 8wk. CONCLUSION The parameters of ONH are most sensitive to elevated IOP in a primate glaucomatous model. These findings suggest that we should focus on those parameters instead of RNFL thickness in patients with elevated IOP, as they might present with earlier glaucomatous changes.
Collapse
Affiliation(s)
- Zhi-Chao Yan
- Department of Ophthalmology, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, Guangdong Province, China.,State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Xue-Jiao Yang
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Hong-Rui Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Shui-Feng Deng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Ying-Ting Zhu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Ye-Hong Zhuo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| |
Collapse
|
28
|
Mori S, Kurimoto T, Kanamori A, Sakamoto M, Ueda K, Yamada-Nakanishi Y, Nakamura M. Discordance of Disc-Fovea Raphe Angles Determined by Optical Coherence Tomography and MP-3 Microperimetry in Eyes With a Glaucomatous Hemifield Defect. Invest Ophthalmol Vis Sci 2019; 60:1403-1411. [PMID: 30943288 DOI: 10.1167/iovs.18-26354] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to evaluate the concordance of a temporal raphe architecture estimated using optical coherence tomography (OCT) and MP-3 microperimetry. Methods We enrolled 25 eyes with either an upper or lower glaucomatous hemifield defect, as detected on the Humphrey visual field 30-2 test. A structural temporal raphe was extrapolated from visible end points of retinal nerve fiber bundles present in a perimetrically normal hemiretina on an en face Spectralis OCT image. A functional temporal raphe was drawn as a line from the fovea to the border of at least a 10-dB difference in sensitivity, at vertically adjacent test points, with at least three consecutive pairs among 25 test points placed at 8° to 18° from the fovea (2° intervals) on the MP-3. An angle determined by the optic disc center, the fovea, and the temporal raphe line (the DFR angle) was calculated. Correlations and agreement of the OCT- and MP-3-derived DFR angles and factors affecting discordance of the two estimates were evaluated. Results Despite no significant demographic differences, the functional DFR angle (mean ± SD, 171.8° ± 3.5°) was significantly larger than that of the structural DFR angle (166.5° ± 3.2°) in 14 eyes with upper hemifield defects and vice versa in 11 eyes with lower hemifield defects (163.4° ± 3.0° vs. 170.5° ± 3.2°). The mean deviation was significantly associated with the functional and structural DFR angle difference in eyes with only upper hemifield defects. Conclusions The structural temporal raphe was more deviated to the perimetrically normal hemiretina side than to the functional temporal raphe, thereby suggesting that a structural change may precede a functional loss.
Collapse
Affiliation(s)
- Sotaro Mori
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takuji Kurimoto
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Akiyasu Kanamori
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Mari Sakamoto
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kaori Ueda
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yuko Yamada-Nakanishi
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Makoto Nakamura
- Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan
| |
Collapse
|
29
|
Ly A, Phu J, Katalinic P, Kalloniatis M. An evidence-based approach to the routine use of optical coherence tomography. Clin Exp Optom 2018; 102:242-259. [PMID: 30560558 PMCID: PMC6590481 DOI: 10.1111/cxo.12847] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/13/2018] [Accepted: 10/05/2018] [Indexed: 02/06/2023] Open
Abstract
Optical coherence tomography is an imaging technology that has revolutionised the detection, assessment and management of ocular disease. It is now a mainstream technology in clinical practice and is performed by non-specialised personnel in some settings. This article provides a clinical perspective on the implications of that movement and describes best practice using multimodal imaging and an evidence-based approach. Practical, illustrative guides on the interpretation of optical coherence tomography are provided for three major diseases of the ocular fundus, in which optical coherence tomography is often crucial to management: age-related macular degeneration, diabetic retinopathy and glaucoma. Topics discussed include: cross-sectional and longitudinal signs in ocular disease, so-called 'red-green' disease whereby clinicians rely on machine/statistical comparisons for diagnosis in managing treatment-naïve patients, and the utility of optical coherence tomography angiography and machine learning.
Collapse
Affiliation(s)
- Angelica Ly
- Centre for Eye Health, The University of New South Wales, Sydney, New South Wales, Australia.,Faculty of Science, School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
| | - Jack Phu
- Centre for Eye Health, The University of New South Wales, Sydney, New South Wales, Australia.,Faculty of Science, School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
| | - Paula Katalinic
- Centre for Eye Health, The University of New South Wales, Sydney, New South Wales, Australia.,Faculty of Science, School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
| | - Michael Kalloniatis
- Centre for Eye Health, The University of New South Wales, Sydney, New South Wales, Australia.,Faculty of Science, School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
30
|
Ledolter J, Kardon RH. Assessing Trends in Functional and Structural Characteristics: A Survey of Statistical Methods With an Example From Ophthalmology. Transl Vis Sci Technol 2018; 7:34. [PMID: 30402341 PMCID: PMC6213778 DOI: 10.1167/tvst.7.5.34] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 09/08/2018] [Indexed: 11/24/2022] Open
Abstract
Purpose Clinical decisions on treatment are usually based on short-term records of consecutive measurements of structure and function. Useful models for analyzing average trends and a description of statistical methods for classifying individual subjects on the basis of subject-specific trend progressions are presented. Methods Random effects trend models allow intercepts and slopes of the trend regression to vary across subjects around group-specific mean intercepts and mean slopes. Model results assess whether average intercepts and slopes and subject variability in intercepts and slopes are the same across groups. Fisher's discriminant functions are used for classification. Results Methods are presented and illustrated on structural visual data from a multiyear perimetry study. Average thickness of the ganglion cell layer from the optical coherence tomography macula scan and of the retinal nerve fiber layer from the optic disc scan for both glaucoma patients on optimal treatment and normal subjects are analyzed. The random effects trend model shows that average intercepts of glaucoma patients and normal subjects are quite different, but that average slopes are the same, and that the subject variability in both intercepts and slopes is larger for the glaucoma group. These findings explain why the subject-specific trend progression is not a good classifier; it is the level of the measurement (intercept or baseline value) that carries useful information in this particular cohort example. Translational Relevance Clinicians base decisions on short-term records of consecutive measurements and need simple statistical tools to analyze the information. This paper discusses useful methods for analyzing short time series data. Model results assess whether there exist significant trends and whether average trends are different across groups. The paper discusses whether clinical measures classify patients reliably into disease groups, given their variability. With ever more available data, classification plays a central role of personalized medicine.
Collapse
Affiliation(s)
- Johannes Ledolter
- Department of Management Sciences at the University of Iowa, Iowa City, IA, USA.,Iowa City VA Medical Center, Iowa City, IA, USA
| | - Randy H Kardon
- Iowa City VA Medical Center, Iowa City, IA, USA.,Department of Ophthalmology and Visual Sciences at the University of Iowa Hospital, Iowa City, IA, USA
| |
Collapse
|
31
|
Leitgeb RA, Baumann B. Multimodal Optical Medical Imaging Concepts Based on Optical Coherence Tomography. FRONTIERS IN PHYSICS 2018; 6. [PMID: 0 DOI: 10.3389/fphy.2018.00114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
|
32
|
Santos CY, Johnson LN, Sinoff SE, Festa EK, Heindel WC, Snyder PJ. Change in retinal structural anatomy during the preclinical stage of Alzheimer's disease. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2018; 10:196-209. [PMID: 29780864 PMCID: PMC5956814 DOI: 10.1016/j.dadm.2018.01.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
INTRODUCTION We conducted a 27-month longitudinal study of mid-life adults with preclinical Alzheimer's disease (AD), using spectral domain optical coherence tomography to compare changes in volume and thickness in all retinal neuronal layers to those of age-matched healthy control subjects. METHODS Fifty-six older adults (mean age = 65.36 years) with multiple risk factors for AD completed spectral domain optical coherence tomography retinal imaging and cognitive testing at baseline. Twenty-seven months later, they completed the same examinations and an 18F-florbetapir positron emission tomography imaging study. RESULTS Compared to healthy control subjects, those in the preclinical stage of AD showed a significant decrease in macular retinal nerve fiber layer (mRNFL) volume, over a 27-month follow-up interval period, as well as a decrease in outer nuclear layer and inner plexiform layer volumes and thickness in the inferior quadrant. However, only the mRNFL volume was linearly related to neocortical positron emission tomography amyloid standardized uptake value ratio after controlling for any main effects of age (R2 = 0.103; ρ = 0.017). Furthermore, the magnitude of mRNFL volume reduction was significantly correlated with performance on a task of participants' abilities to efficiently integrate visual and auditory speech information (McGurk effect). DISCUSSION We observed a decrease in mRNFL, outer nuclear layer, and inner plexiform layer volumes, in preclinical AD relative to controls. Moreover, the largely myelinated axonal loss in the RNFL is related to increased neocortical amyloid-β accumulation after controlling for age. Volume loss in the RNFL, during the preclinical stage, is not related to performance on measures of episodic memory or problem solving. However, this retinal change does appear to be modestly related to relative decrements in performance on a measure of audiovisual integration efficiency that has been recently advanced as a possible early cognitive marker of mild cognitive impairment.
Collapse
Affiliation(s)
- Cláudia Y. Santos
- Interdisciplinary Neuroscience Program, University of Rhode Island, Kingston, RI, USA
- Lifespan Clinical Research Center, Rhode Island Hospital, Providence, RI, USA
| | - Lenworth N. Johnson
- Lifespan Clinical Research Center, Rhode Island Hospital, Providence, RI, USA
- Department of Ophthalmology, Rhode Island Hospital & Alpert Medical School of Brown University, Providence, RI, USA
| | - Stuart E. Sinoff
- Department of Ophthalmology, BayCare Medical Group, Clearwater, FL, USA
| | - Elena K. Festa
- Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, Providence, RI, USA
| | - William C. Heindel
- Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, Providence, RI, USA
| | - Peter J. Snyder
- Interdisciplinary Neuroscience Program, University of Rhode Island, Kingston, RI, USA
- Lifespan Clinical Research Center, Rhode Island Hospital, Providence, RI, USA
- Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI, USA
| |
Collapse
|
33
|
Attenuation Coefficients From SD-OCT Data: Structural Information Beyond Morphology on RNFL Integrity in Glaucoma. J Glaucoma 2017; 26:1001-1009. [PMID: 28858153 DOI: 10.1097/ijg.0000000000000764] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The purpose of this study is to explore the attenuation coefficient (AC) of the retinal nerve fiber layer (RNFL) in spectral domain optical coherence tomography (OCT) images, in healthy eyes and eyes affected by glaucoma. To assess the relation between RNLF AC, disease severity, RNFL thickness, visual field sensitivity threshold, spatial location and age. PATIENTS AND METHODS We analyzed peripapillary circle scans of a clinical OCT device (Spectralis OCT, Heidelberg Engineering, Heidelberg, Germany) in 102 glaucoma patients and 90 healthy controls. The images were fully automatically converted into depth-resolved AC images. Next, the median AC within the RNFL was calculated based on the Spectralis segmentation. We compared the RNFL AC between healthy, mild, moderate and advanced glaucomatous eyes and assessed the correlation with patient characteristics such as age and visual field sensitivity threshold (HFA, Carl Zeiss Meditec, Dublin, CA) in a generalized estimating equations (GEE) model. Finally, we explored the ability to discriminate between glaucomatous and healthy eyes by RNFL AC. RESULTS Median RNFL AC decreased with increasing disease severity up to moderate glaucoma (P<0.001) in all 4 sectors around the optic nerve head. The largest relative decrease occurred in the nasal sector. The RNFL AC (AUC, 0.834±0.028) effectively discriminated healthy from glaucomatous eyes, although RNFL thickness (AUC, 0.975±0.013) performed even better (P<0.001). Prediction of visual field sensitivity improved significantly when RNFL thickness was augmented with RNFL AC as covariates (P<0.001). CONCLUSIONS This study demonstrated that RNFL AC provides complementary information on the RNFL's health compared with RNFL thickness measurements alone.
Collapse
|
34
|
Ivers KM, Yang H, Gardiner SK, Qin L, Reyes L, Fortune B, Burgoyne CF. In Vivo Detection of Laminar and Peripapillary Scleral Hypercompliance in Early Monkey Experimental Glaucoma. Invest Ophthalmol Vis Sci 2017; 57:OCT388-403. [PMID: 27409498 PMCID: PMC4968772 DOI: 10.1167/iovs.15-18666] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To compare optical coherence tomography (OCT) detected, optic nerve head (ONH) compliance within control and experimental glaucoma (EG) eyes of 15 monkeys at EG onset. Methods Intraocular pressure (IOP) was chronically elevated in one eye of each animal using a laser. Experimental glaucoma onset was identified using confocal scanning laser tomography (CSLT). Optical coherence tomography ONH imaging (40 radial B-scans) was performed at 10 mm Hg before and after laser. At EG onset, OCT scans were obtained at IOP 10 and 30 mm Hg. Optical coherence tomography landmarks within the IOP 10/30 images were delineated to quantify IOP 10/30 differences (compliance) for anterior lamina cribrosa surface depth (ALCSD) relative to Bruch's membrane opening (BMO) (ALCSD-BMO), ALCSD relative to peripheral BM (ALCSD-BM), and BMO depth relative to peripheral BM (BMOD-BM). A linear mixed effects model assessed for acute IOP elevation effects, control versus EG eye effects, and their interaction Results Effects of IOP elevation were greater in EG versus control eyes for ALCSD-BMO (−46 ± 45 vs. −8 ± 13 μm, P = 0.0042) and ALCSD-BM (−92 ± 64 vs. −42 ± 22 μm, P = 0.0075). Experimental glaucoma eye-specific ALCSD-BMO and ALCSD-BM compliance exceeded the range of control eye compliance in 9 and 8 of the 15 EG eyes, respectively. Post-laser peak IOP (R2 = 0.798, P < 0.0001) and post-laser mean IOP (R2 = 0.634, P < 0.0004) most strongly correlated to EG versus control eye differences in ALCSD-BMO compliance. Conclusions Laminar (ALCSD-BMO) and peripapillary scleral (ALCSD-BM) hypercompliance are present in most monkey eyes at the onset of EG.
Collapse
Affiliation(s)
- Kevin M Ivers
- Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States 2Discoveries in Sight Research Laboratories of the Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Hongli Yang
- Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States 2Discoveries in Sight Research Laboratories of the Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Stuart K Gardiner
- Discoveries in Sight Research Laboratories of the Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Lirong Qin
- Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Luke Reyes
- Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Brad Fortune
- Discoveries in Sight Research Laboratories of the Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| | - Claude F Burgoyne
- Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States 2Discoveries in Sight Research Laboratories of the Devers Eye Institute, Legacy Research Institute, Portland, Oregon, United States
| |
Collapse
|
35
|
Fortune B, Hardin C, Reynaud J, Cull G, Yang H, Wang L, Burgoyne CF. Comparing Optic Nerve Head Rim Width, Rim Area, and Peripapillary Retinal Nerve Fiber Layer Thickness to Axon Count in Experimental Glaucoma. Invest Ophthalmol Vis Sci 2017; 57:OCT404-12. [PMID: 27409499 PMCID: PMC4968911 DOI: 10.1167/iovs.15-18667] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose We compare spectral-domain optical coherence tomography (SDOCT) measurements of minimum rim width (MRW), minimum rim area (MRA), and peripapillary retinal nerve fiber layer thickness (RNFLT) to complete orbital optic nerve axon counts in nonhuman primates (NHP) with unilateral experimental glaucoma (EG). Methods Biweekly SDOCT measurements of MRW, MRA, and RNFLT were acquired under manometric IOP control (10 mm Hg) in 51 NHP during baseline (mean ± SD, 5.0 ± 1.6 sessions) and after laser photocoagulation was applied to the trabecular meshwork of one eye to induce chronic IOP elevation. At the study endpoint (predefined for each NHP), 100% axon counts were obtained from each optic nerve. Results For SDOCT parameters at baseline, the correlation between the two eyes of each animal was strongest for RNFLT (R = 0.97) and MRW (R = 0.97), but lower for MRA (R = 0.85). At the final time point, average values in EG eyes relative to control eyes were: −22% for RNFLT, −38% for MRW, −36% for MRA, and −36% for optic nerve axons. The correlation with axon counts was strongest for RNFLT (R = 0.81), compared to MRW (R = 0.72, P = 0.001) or MRA (R = 0.70, P = 0.001). Diagnostic sensitivity was 75% for RNFLT, 90% for MRW, and 88% for MRA; all had 100% specificity. Conclusions Peripapillary RNFLT was correlated more closely with total orbital optic nerve axon count than were the ONH parameters MRW or MRA. This is likely because glaucomatous deformation (beyond axon loss alone) has a greater influence on the ONH parameters MRW and MRA than on RNFLT.
Collapse
|
36
|
Fortune B, Reynaud J, Hardin C, Wang L, Sigal IA, Burgoyne CF. Experimental Glaucoma Causes Optic Nerve Head Neural Rim Tissue Compression: A Potentially Important Mechanism of Axon Injury. Invest Ophthalmol Vis Sci 2017; 57:4403-11. [PMID: 27564522 PMCID: PMC5016000 DOI: 10.1167/iovs.16-20000] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Purpose We tested the hypothesis that experimental glaucoma (EG) results in greater thinning of the optic nerve head (ONH) neural rim tissue than the peripapillary retinal nerve fiber layer (RNFL) tissue. Methods Longitudinal spectral-domain optical coherence tomography (SDOCT) imaging of the ONH and peripapillary RNFL was performed every other week under manometric IOP control (10 mm Hg) in 51 nonhuman primates (NHP) during baseline and after induction of unilateral EG. The ONH parameter minimum rim area (MRA) was derived from 80 radial B-scans centered on the ONH; RNFL cross-sectional area (RNFLA) from a peripapillary circular B-scan with 12° diameter. Results In control eyes, MRA was 1.00 ± 0.19 mm2 at baseline and 1.00 ± 0.19 mm2 at the final session (P = 0.77), while RNFLA was 0.95 ± 0.09 and 0.95 ± 0.10 mm2, respectively (P = 0.96). In EG eyes, MRA decreased from 1.00 ± 0.19 mm2 at baseline to 0.63 ± 0.21 mm2 at the final session (P < 0.0001), while RNFLA decreased from 0.95 ± 0.09 to 0.74 ± 0.19 mm2, respectively (P < 0.0001). Thus, MRA decreased by 36.4 ± 20.6% in EG eyes, significantly more than the decrease in RNFLA (21.7 ± 19.4%, P < 0.0001). Other significant changes in EG eyes included increased Bruch's membrane opening (BMO) nonplanarity (P < 0.05), decreased BMO aspect ratio (P < 0.0001), and decreased MRA angle (P < 0.001). Bruch's membrane opening area did not change from baseline in either control or EG eyes (P = 0.27, P = 0.15, respectively). Conclusions Optic nerve head neural rim tissue thinning exceeded peripapillary RNFL thinning in NHP EG. These results support the hypothesis that axon bundles are compressed transversely within the ONH rim along with glaucomatous deformation of connective tissues.
Collapse
Affiliation(s)
- Brad Fortune
- Discoveries in Sight Research Laboratories Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, Oregon, United States
| | - Juan Reynaud
- Discoveries in Sight Research Laboratories Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, Oregon, United States
| | - Christy Hardin
- Discoveries in Sight Research Laboratories Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, Oregon, United States
| | - Lin Wang
- Discoveries in Sight Research Laboratories Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, Oregon, United States
| | - Ian A Sigal
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Claude F Burgoyne
- Discoveries in Sight Research Laboratories Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, Oregon, United States
| |
Collapse
|
37
|
Polarization Sensitive Optical Coherence Tomography: A Review of Technology and Applications. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7050474] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
38
|
de Boer JF, Hitzenberger CK, Yasuno Y. Polarization sensitive optical coherence tomography - a review [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:1838-1873. [PMID: 28663869 PMCID: PMC5480584 DOI: 10.1364/boe.8.001838] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/16/2017] [Accepted: 02/16/2017] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT) is now a well-established modality for high-resolution cross-sectional and three-dimensional imaging of transparent and translucent samples and tissues. Conventional, intensity based OCT, however, does not provide a tissue-specific contrast, causing an ambiguity with image interpretation in several cases. Polarization sensitive (PS) OCT draws advantage from the fact that several materials and tissues can change the light's polarization state, adding an additional contrast channel and providing quantitative information. In this paper, we review basic and advanced methods of PS-OCT and demonstrate its use in selected biomedical applications.
Collapse
Affiliation(s)
- Johannes F. de Boer
- Department of Physics and Astronomy, LaserLaB Amsterdam, VU University, Amsterdam, The Netherlands
- Authors were listed in alphabetical order and contributed equally to the manuscript
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Authors were listed in alphabetical order and contributed equally to the manuscript
| | - Yoshiaki Yasuno
- Computational Optics Group, University of Tsukuba, Tsukuba, Japan
- Authors were listed in alphabetical order and contributed equally to the manuscript
| |
Collapse
|
39
|
Comparing three different modes of electroretinography in experimental glaucoma: diagnostic performance and correlation to structure. Doc Ophthalmol 2017; 134:111-128. [PMID: 28243926 DOI: 10.1007/s10633-017-9578-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 02/13/2017] [Indexed: 10/20/2022]
Abstract
PURPOSE To compare diagnostic performance and structure-function correlations of multifocal electroretinogram (mfERG), full-field flash ERG (ff-ERG) photopic negative response (PhNR) and transient pattern-reversal ERG (PERG) in a non-human primate (NHP) model of experimental glaucoma (EG). METHODS At baseline and after induction of chronic unilateral IOP elevation, 43 NHP had alternating weekly recordings of retinal nerve fiber layer thickness (RNFLT) by spectral domain OCT (Spectralis) and retinal function by mfERG (7F slow-sequence stimulus, VERIS), ff-ERG (red 0.42 log cd-s/m2 flashes on blue 30 scotopic cd/m2 background, LKC UTAS-E3000), and PERG (0.8° checks, 99% contrast, 100 cd/m2 mean, 5 reversals/s, VERIS). All NHP were followed at least until HRT-confirmed optic nerve head posterior deformation, most to later stages. mfERG responses were filtered into low- and high-frequency components (LFC, HFC, >75 Hz). Peak-to-trough amplitudes of LFC features (N1, P1, N2) and HFC RMS amplitudes were measured and ratios calculated for HFC:P1 and N2:P1. ff-ERG parameters included A-wave (at 10 ms), B-wave (trough-to-peak) and PhNR (baseline-to-trough) amplitudes as well as PhNR:B-wave ratio. PERG parameters included P50 and N95 amplitudes as well as N95:P50 ratio and N95 slope. Diagnostic performance of retinal function parameters was compared using the area under the receiver operating characteristic curve (A-ROC) to discriminate between EG and control eyes. Correlations to RNFLT were compared using Steiger's test. RESULTS Study duration was 15 ± 8 months. At final follow-up, structural damage in EG eyes measured by RNFLT ranged from 9% above baseline (BL) to 58% below BL; 29/43 EG eyes (67%) and 0/43 of the fellow control eyes exhibited significant (>7%) loss of RNFLT from BL. Using raw parameter values, the largest A-ROC findings for mfERG were: HFC (0.82) and HFC:P1 (0.90); for ff-ERG: PhNR (0.90) and PhNR:B-wave (0.88) and for PERG: P50 (0.64) and N95 (0.61). A-ROC increased when data were expressed as % change from BL, but the pattern of results persisted. At 95% specificity, the diagnostic sensitivity of mfERG HFC:P1 ratio was best, followed by PhNR and PERG. The correlation to RNFLT was stronger for mfERG HFC (R = 0.65) than for PhNR (R = 0.59) or PERG N95 (R = 0.36), (p = 0.20, p = 0.0006, respectively). The PhNR flagged a few EG eyes at the final time point that had not been flagged by mfERG HFC or PERG. CONCLUSIONS Diagnostic performance and structure-function correlation were strongest for mfERG HFC as compared with ff-ERG PhNR or PERG in NHP EG.
Collapse
|
40
|
Huang XR, Knighton RW, Spector YZ, Feuer WJ. Cytoskeletal Alteration and Change of Retinal Nerve Fiber Layer Birefringence in Hypertensive Retina. Curr Eye Res 2017; 42:936-947. [PMID: 28094584 DOI: 10.1080/02713683.2016.1262043] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE Glaucoma damages the retinal nerve fiber layer (RNFL). Both RNFL thickness and retardance can be used to assess the damage, but birefringence, the ratio of retardance to thickness, is a property of the tissue itself. This study investigated the relationship between axonal cytoskeleton and RNFL birefringence in retinas with hypertensive damage. MATERIALS AND METHODS High intraocular pressure (IOP) was induced unilaterally in rat eyes. RNFL retardance in isolated retinas was measured. Cytostructural organization and bundle thickness were evaluated by confocal imaging of immunohistochemical staining of the cytoskeletal components: microtubules (MTs), F-actin, and neurofilaments. Bundles with different appearances of MT stain were studied, and their birefringence was calculated at different radii from the optic nerve head (ONH) center. RESULTS Forty bundles in eight normal retinas and 37 bundles in 10 treated retinas were examined. In normal retinas, the stain of axonal cytoskeleton was approximately uniform within bundles, and RNFL birefringence did not change along bundles. In treated retinas, elevation of IOP caused non-uniform alteration of axonal cytoskeleton across the retina, and distortion of axonal MTs was associated with decreased birefringence. The study further demonstrated that change of RNFL birefringence profiles along bundles can imply altered axonal cytoskeleton, suggesting that ultrastructural change of the RNFL can be inferred from clinical measurements of RNFL birefringence. The study also demonstrated that measuring RNFL birefringence profiles along bundles, instead of at a single location, may provide a more sensitive way to detect axonal ultrastructural change. CONCLUSIONS Measurement of RNFL birefringence along bundles can provide estimation of cytoskeleton alteration and sensitive detection of glaucomatous damage.
Collapse
Affiliation(s)
- Xiang-Run Huang
- a Bascom Palmer Eye Institute , Miller School of Medicine University of Miami , Miami , FL , USA.,b Department of Biomedical Engineering , College of Engineering University of Miami , Coral Gables , FL , USA
| | - Robert W Knighton
- a Bascom Palmer Eye Institute , Miller School of Medicine University of Miami , Miami , FL , USA
| | - Ye Z Spector
- a Bascom Palmer Eye Institute , Miller School of Medicine University of Miami , Miami , FL , USA.,b Department of Biomedical Engineering , College of Engineering University of Miami , Coral Gables , FL , USA
| | - William J Feuer
- a Bascom Palmer Eye Institute , Miller School of Medicine University of Miami , Miami , FL , USA
| |
Collapse
|
41
|
Fialová S, Augustin M, Fischak C, Schmetterer L, Handschuh S, Glösmann M, Pircher M, Hitzenberger CK, Baumann B. Posterior rat eye during acute intraocular pressure elevation studied using polarization sensitive optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2017; 8:298-314. [PMID: 28101419 PMCID: PMC5231300 DOI: 10.1364/boe.8.000298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/01/2016] [Accepted: 12/12/2016] [Indexed: 05/05/2023]
Abstract
Polarization sensitive optical coherence tomography (PS-OCT) operating at 840 nm with axial resolution of 3.8 µm in tissue was used for investigating the posterior rat eye during an acute intraocular pressure (IOP) increase experiment. IOP was elevated in the eyes of anesthetized Sprague Dawley rats by cannulation of the anterior chamber. Three dimensional PS-OCT data sets were acquired at IOP levels between 14 mmHg and 105 mmHg. Maps of scleral birefringence, retinal nerve fiber layer (RNFL) retardation and relative RNFL/retina reflectivity were generated in the peripapillary area and quantitatively analyzed. All investigated parameters showed a substantial correlation with IOP. In the low IOP range of 14-45 mmHg only scleral birefringence showed statistically significant correlation. The polarization changes observed in the PS-OCT imaging study presented in this work suggest that birefringence of the sclera may be a promising IOP-related parameter to investigate.
Collapse
Affiliation(s)
- Stanislava Fialová
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Corinna Fischak
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
- Department of Clinical Pharmacology, General Hospital and Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Leopold Schmetterer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
- Department of Clinical Pharmacology, General Hospital and Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
- Singapore Eye Research Institute, The Academia, 20 College Road, Discovery Tower Level 6, 169856 Singapore, Republic of Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, 11 Mandalay Road, 308232 Singapore, Republic of Singapore
| | - Stephan Handschuh
- VetCore Facility for Research and Technology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
| | - Martin Glösmann
- VetCore Facility for Research and Technology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| |
Collapse
|
42
|
Hood DC, De Cuir N, Blumberg DM, Liebmann JM, Jarukasetphon R, Ritch R, De Moraes CG. A Single Wide-Field OCT Protocol Can Provide Compelling Information for the Diagnosis of Early Glaucoma. Transl Vis Sci Technol 2016; 5:4. [PMID: 27847691 PMCID: PMC5106198 DOI: 10.1167/tvst.5.6.4] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 09/22/2016] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate a report for glaucoma diagnosis based on a single optical coherence tomography (OCT) protocol. Methods A wide-field (9 × 12 mm) swept-source (SS) OCT scan, encompassing the macula and disc, was obtained on 130 eyes (patients) with or suspected open-angle glaucoma, a mean deviation greater than or equal to −6 dB on a 24-2 visual field (VF), and spherical refractive error between ± 6 diopters (D). The single-page report contained a circumpapillary retinal nerve fiber layer (cpRNFL) thickness plot; retinal ganglion cell layer and retinal nerve fiber layer (RNFL) thickness and probability plots of the macula and optic nerve; and an enface slab image of the optic nerve. A report specialist judged each eye as healthy (H); probably healthy (PH); forced-choice healthy (FC-H); optic neuropathy (ON); probably ON (PON); forced-choice optic neuropathy (FC-ON). Two glaucoma specialists made similar judgments about the presence of glaucomatous damage. The glaucoma specialists had 24-2 and 10-2 VFs, fundus photos, patient chart information, and the single-page report including the report specialist's interpretation. Results The reference standard consisted of 57 eyes judged as glaucomatous (ON or PON) and 45 eyes judged as healthy (H or PH) by both glaucoma specialists. The report specialist identified 56 of the glaucomatous eyes as optic neuropathy (i.e., ON, PON, or FC-ON), and 44 of the healthy eyes as healthy (i.e., H, PH, or FC-H), an accuracy of 98.0%. Conclusions A single-page report based upon a single, wide-field OCT scan has the information needed to diagnose early glaucoma with excellent sensitivity/specificity. Translational Relevance It is possible that screening for glaucoma can be effective with only a single OCT protocol.
Collapse
Affiliation(s)
- Donald C Hood
- Department of Psychology, Columbia University, New York, NY, USA ; Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Nicole De Cuir
- Department of Psychology, Columbia University, New York, NY, USA ; The College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Dana M Blumberg
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | | | - Ravivarn Jarukasetphon
- Einhorn Clinical Research Center, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | - Robert Ritch
- Einhorn Clinical Research Center, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | | |
Collapse
|
43
|
Wilsey LJ, Reynaud J, Cull G, Burgoyne CF, Fortune B. Macular Structure and Function in Nonhuman Primate Experimental Glaucoma. Invest Ophthalmol Vis Sci 2016; 57:1892-900. [PMID: 27082305 PMCID: PMC4849889 DOI: 10.1167/iovs.15-18119] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate structure and function of macular retinal layers in nonhuman primate (NHP) experimental glaucoma (EG). Methods Twenty-one NHP had longitudinal imaging of macular structure by SDOCT, 16 also had recordings of function by multifocal ERG. The average thickness over 15° was derived for seven individual SDOCT layers: macular nerve fiber layer (m-NFL), retinal ganglion cell layer (RGCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer+inner segments combined (ONL+IS), and outer segments (OS). Peripapillary RNFL thickness (ppRNFLT) was measured from a single circular B-scan with 12° diameter. Responses to a slow-sequence multifocal ERG (mfERG) stimulus (7F) were filtered (at 75 Hz) into low- and high-frequency components (LFC, HFC). Results At final follow-up, significant structural loss occurred only in EG eyes and only for ppRNFLT (−29 ± 23%), m-NFL (−17 ± 16%), RGCL (−22 ± 15%), and IPL (−19 ± 14%); though there was also a small increase in OPL (+6 ± 7%) and ONL+IS (4 ± 4%) and a similar tendency for INL. Macular structural loss was correlated with ppRNFLT only for the NFL, RGCL and IPL (R = 0.95, 0.93 and 0.95, respectively, P < 0.0001). Significant functional loss occurred only for HFC and N2 in EG eyes. Significant longitudinal structure–function correlations (P < 0.01) were observed only in EG eyes and only for mfERG HFC and N2: HFC was correlated with ppRNFLT (R = 0.69), macular NFL (R = 0.67), RGCL (R = 0.74), and IPL (R = 0.72); N2 was correlated with RGCL (R = 0.54) and IPL (R = 0.48). High-frequency components amplitude change was inversely correlated with outer retinal thickness change (= −0.66). Conclusions Macular structural and functional losses are correlated and specific to ganglion cells over a wide range of EG severity. Outer retinal changes are likely due to inner retinal loss.
Collapse
|
44
|
Quigley HA. Understanding Glaucomatous Optic Neuropathy: The Synergy Between Clinical Observation and Investigation. Annu Rev Vis Sci 2016; 2:235-254. [PMID: 28532352 DOI: 10.1146/annurev-vision-111815-114417] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Glaucoma is a complex disorder of aging defined by the death of retinal ganglion cells and remodeling of connective tissues at the optic nerve head. Intraocular pressure-induced axonal injury at the optic nerve head leads to apoptosis. Loss of retinal ganglion cells follows a slowly progressive sequence. Clinical features of the disease have suggested and corroborated pathological events. The death of retinal ganglion cells causes secondary loss of neurons in the brain, but only as a by-product of injury to the retinal ganglion cells. Although therapy to lower intraocular pressure is moderately effective, new treatments are being developed to alter the remodeling of ocular connective tissue, to interrupt the injury signal from axon to soma, and to upregulate a variety of survival mechanisms.
Collapse
Affiliation(s)
- Harry A Quigley
- Glaucoma Center of Excellence, Wilmer Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287;
| |
Collapse
|
45
|
Automatic quantitative analysis of experimental primary and secondary retinal neurodegeneration: implications for optic neuropathies. Cell Death Discov 2016. [DOI: 10.1038/cddiscovery.2016.31 ecollection 2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
46
|
Automatic quantitative analysis of experimental primary and secondary retinal neurodegeneration: implications for optic neuropathies. Cell Death Discov 2016; 2:16031. [PMID: 27551521 PMCID: PMC4979431 DOI: 10.1038/cddiscovery.2016.31] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/15/2016] [Indexed: 01/03/2023] Open
Abstract
Secondary neurodegeneration is thought to play an important role in the pathology of neurodegenerative disease, which potential therapies may target. However, the quantitative assessment of the degree of secondary neurodegeneration is difficult. The present study describes a novel algorithm from which estimates of primary and secondary degeneration are computed using well-established rodent models of partial optic nerve transection (pONT) and ocular hypertension (OHT). Brn3-labelled retinal ganglion cells (RGCs) were identified in whole-retinal mounts from which RGC density, nearest neighbour distances and regularity indices were determined. The spatial distribution and rate of RGC loss were assessed and the percentage of primary and secondary degeneration in each non-overlapping segment was calculated. Mean RGC number (82 592±681) and RGC density (1695±23.3 RGC/mm2) in naïve eyes were comparable with previous studies, with an average decline in RGC density of 71±17 and 23±5% over the time course of pONT and OHT models, respectively. Spatial analysis revealed greatest RGC loss in the superior and central retina in pONT, but significant RGC loss in the inferior retina from 3 days post model induction. In comparison, there was no significant difference between superior and inferior retina after OHT induction, and RGC loss occurred mainly along the superior/inferior axis (~30%) versus the nasal–temporal axis (~15%). Intriguingly, a significant loss of RGCs was also observed in contralateral eyes in experimental OHT. In conclusion, a novel algorithm to automatically segment Brn3a-labelled retinal whole-mounts into non-overlapping segments is described, which enables automated spatial and temporal segmentation of RGCs, revealing heterogeneity in the spatial distribution of primary and secondary degenerative processes. This method provides an attractive means to rapidly determine the efficacy of neuroprotective therapies with implications for any neurodegenerative disorder affecting the retina.
Collapse
|
47
|
Ferrandez B, Ferreras A, Calvo P, Abadia B, Marin JM, Pajarin AB. Assessment of the retinal nerve fiber layer in individuals with obstructive sleep apnea. BMC Ophthalmol 2016; 16:40. [PMID: 27090783 PMCID: PMC4835866 DOI: 10.1186/s12886-016-0216-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 04/12/2016] [Indexed: 01/06/2023] Open
Abstract
Background The effect of obstructive sleep apnea (OSA) syndrome in the peripapillary retinal nerve fiber layer (RNFL) thicknesses remains unclear. The purpose of this study was to assess RNFL measurements acquired using scanning laser polarimetry (SLP) and optical coherence tomography (OCT) in patients with OSA. Methods The sample of this cross-sectional study included 40 OSA patients and 45 age-matched controls, consecutively and prospectively selected. All participants underwent at least one reliable standard automated perimetry (SAP) test, while RNFL measurements were obtained using the SLP and OCT. The OSA group was divided into 3 sub-groups based on the apnea/hypopnea index (AHI): mild, moderate, or severe OSA. SAP, SLP, and OCT outcomes were compared between the control and OSA groups. The relationship between AHI and RNFL parameters was also evaluated. Results Age was not different between both groups. Mean deviation of SAP was −0.47 ± 0.9 dB and −1.43 ± 2.3 dB in the control and OSA groups, respectively (p = 0.01). RNFL thickness measured with OCT was similar between groups. OSA patients showed increased nerve fiber indicator (NFI; 20.9 ± 7.9 versus 16.42 ± 7.82; p = 0.01) and decreased superior average (59.74 ± 10.35 versus 63.73 ± 6.58; p = 0.03) obtained with SLP compared with healthy individuals. In the total sample, NFI and AHI were moderately correlated (r = 0.358; p = 0.001). In severe OSA subjects (n = 22), NFI and AHI had a Spearman correlation coefficient of 0.44 (p = 0.04). Conclusion RNFL thickness measured with OCT did not differ significantly between groups. Severe OSA was related to a reduction of the RNFL thickness assessed by SLP.
Collapse
Affiliation(s)
- Blanca Ferrandez
- Department of Ophthalmology, IIS-Aragon, Miguel Servet University Hospital, Isabel la Catolica 1-3, 50009, Zaragoza, Spain
| | - Antonio Ferreras
- Department of Ophthalmology, IIS-Aragon, Miguel Servet University Hospital, Isabel la Catolica 1-3, 50009, Zaragoza, Spain. .,University of Zaragoza, Zaragoza, Spain.
| | - Pilar Calvo
- Department of Ophthalmology, IIS-Aragon, Miguel Servet University Hospital, Isabel la Catolica 1-3, 50009, Zaragoza, Spain.,University of Zaragoza, Zaragoza, Spain
| | - Beatriz Abadia
- Department of Ophthalmology, IIS-Aragon, Miguel Servet University Hospital, Isabel la Catolica 1-3, 50009, Zaragoza, Spain
| | - Jose M Marin
- University of Zaragoza, Zaragoza, Spain.,Department of Pneumology, Miguel Servet University Hospital, Zaragoza, Spain
| | | |
Collapse
|
48
|
Fialová S, Augustin M, Glösmann M, Himmel T, Rauscher S, Gröger M, Pircher M, Hitzenberger CK, Baumann B. Polarization properties of single layers in the posterior eyes of mice and rats investigated using high resolution polarization sensitive optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2016; 7:1479-95. [PMID: 27446670 PMCID: PMC4929656 DOI: 10.1364/boe.7.001479] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/11/2016] [Accepted: 03/14/2016] [Indexed: 05/19/2023]
Abstract
We present a high resolution polarization sensitive optical coherence tomography (PS-OCT) system for ocular imaging in rodents. The system operates at 840 nm and uses a broadband superluminescent diode providing an axial resolution of 5.1 µm in air. PS-OCT data was acquired at 83 kHz A-scan rate by two identical custom-made spectrometers for orthogonal polarization states. Pigmented (Brown Norway, Long Evans) and non-pigmented (Sprague Dawley) rats as well as pigmented mice (C57BL/6) were imaged. Melanin pigment related depolarization was analyzed in the retinal pigment epithelium (RPE) and choroid of these animals using the degree of polarization uniformity (DOPU). For all rat strains, significant differences between RPE and choroidal depolarization were observed. In contrast, DOPU characteristics of RPE and choroid were similar for C57BL/6 mice. Moreover, the depolarization within the same tissue type varied significantly between different rodent strains. Retinal nerve fiber layer thickness, phase retardation, and birefringence were mapped and quantitatively measured in Long Evans rats in vivo for the first time. In a circumpapillary annulus, retinal nerve fiber layer birefringence amounted to 0.16°/µm ± 0.02°/µm and 0.17°/µm ± 0.01°/µm for the left and right eyes, respectively.
Collapse
Affiliation(s)
- Stanislava Fialová
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Marco Augustin
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Martin Glösmann
- University of Veterinary Medicine Vienna, Core Facility for Research and Technology, Veterinärplatz 1, 1210 Vienna, Austria
| | - Tanja Himmel
- University of Veterinary Medicine Vienna, Core Facility for Research and Technology, Veterinärplatz 1, 1210 Vienna, Austria
| | - Sabine Rauscher
- Medical University of Vienna, Core Facility Imaging, Lazarettgasse 14, 1090 Vienna, Austria
| | - Marion Gröger
- Medical University of Vienna, Core Facility Imaging, Lazarettgasse 14, 1090 Vienna, Austria
| | - Michael Pircher
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Christoph K. Hitzenberger
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Bernhard Baumann
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090 Vienna, Austria
| |
Collapse
|
49
|
Hood DC, Fortune B, Mavrommatis MA, Reynaud J, Ramachandran R, Ritch R, Rosen RB, Muhammad H, Dubra A, Chui TYP. Details of Glaucomatous Damage Are Better Seen on OCT En Face Images Than on OCT Retinal Nerve Fiber Layer Thickness Maps. Invest Ophthalmol Vis Sci 2015; 56:6208-16. [PMID: 26426403 PMCID: PMC4703406 DOI: 10.1167/iovs.15-17259] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 08/21/2015] [Indexed: 12/21/2022] Open
Abstract
PURPOSE High-resolution images of glaucomatous damage to the retinal nerve fiber layer (RNFL) were obtained with an adaptive optics-scanning light ophthalmoscope (AO-SLO) and used as a basis for comparisons between en face slab images and thickness maps derived from optical coherence tomography (OCT) scans. METHODS Wide-field (9 × 12 mm) cube scans were obtained with swept-source OCT (DRI-OCT) from six eyes of six patients. All eyes had a deep defect near fixation as seen on a 10-2 visual field test. Optical coherence tomography en face images, based on the average reflectance intensity, were generated (ATL 3D-Suite) from 52-μm slabs just below the vitreal border of the inner limiting membrane. The RNFL thickness maps were generated from the same OCT data. Both were compared with the AO-SLO peripapillary images that were previously obtained. RESULTS On AO-SLO images, three eyes showed small regions of preserved and/or missing RNFL bundles within the affected region. Details in these regions were seen on the OCT en face images but not on the RNFL thickness maps. In addition, in the healthier hemi-retinas of two eyes, there were darker, arcuate-shaped regions on en face images that corresponded to abnormalities seen on AO-SLO. These were not seen on RNFL thickness maps. CONCLUSIONS Details of local glaucomatous damage, missing or easily overlooked on traditional OCT RNFL thickness analysis used in clinical OCT reports, were seen on OCT en face images based on the average reflectance intensity. While more work is needed, it is likely that en face slab imaging has a role in the clinical management of glaucoma.
Collapse
Affiliation(s)
- Donald C. Hood
- Departments of Psychology and Ophthalmology Columbia University, New York, New York, United States
| | - Brad Fortune
- Legacy Health, Legacy Research Institute, Portland, Oregon, United States
| | - Maria A. Mavrommatis
- Department of Psychology, Columbia University, New York, New York, United States
| | - Juan Reynaud
- Legacy Health, Legacy Research Institute, Portland, Oregon, United States
| | | | - Robert Ritch
- Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York, United States
| | - Richard B. Rosen
- Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York, United States
| | - Hassan Muhammad
- Department of Psychology, Columbia University, New York, New York, United States
| | - Alfredo Dubra
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Toco Y. P. Chui
- Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York, United States
| |
Collapse
|
50
|
Fortune B, Cull G, Reynaud J, Wang L, Burgoyne CF. Relating Retinal Ganglion Cell Function and Retinal Nerve Fiber Layer (RNFL) Retardance to Progressive Loss of RNFL Thickness and Optic Nerve Axons in Experimental Glaucoma. Invest Ophthalmol Vis Sci 2015; 56:3936-44. [PMID: 26087359 DOI: 10.1167/iovs.15-16548] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To relate changes in retinal function and retinal nerve fiber layer (RNFL) retardance to loss of RNFL thickness and optic nerve axon counts in a nonhuman primate (NHP) model of experimental glaucoma (EG). METHODS Bilateral longitudinal measurements of peripapillary RNFL thickness (spectral-domain optical coherence tomography, SDOCT; Spectralis), retardance (GDxVCC), and multifocal electroretinography (mfERG; VERIS) were performed in 39 NHP at baseline (BL; median, 5 recordings; range, 3-10) and weekly after induction of unilateral EG by laser photocoagulation of the trabecular meshwork. Multifocal ERG responses were high-pass filtered (>75 Hz) to measure high- and low-frequency component (HFC and LFC) amplitudes, including LFC features N1, P1, and N2. High-frequency component amplitudes are known to specifically reflect retinal ganglion cell (RGC) function. Complete (100%) axon counts of orbital optic nerves were obtained in 31/39 NHP. RESULTS Postlaser follow-up was 10.4 ± 7.9 months; mean and peak IOP were 18 ± 5 and 41 ± 11 mm Hg in EG eyes, 11 ± 2 and 18 ± 6 mm Hg in control (CTL) eyes. At the final available time point, RNFL thickness had decreased from BL by 14 ± 14%, retardance by 20 ± 11%, and the mfERG HFC by 30 ± 17% (P < 0.0001 each). Longitudinal changes in retardance and HFC were linearly related to RNFL thickness change (R2 = 0.51, P < 0.0001 and R2 = 0.22, P = 0.002, respectively); LFC N2 was weakly related but N1 or P2 (N1: R2 = 0.07, P = 0.11; P1: R2 = 0.04, P = 0.24; N2: R2 = 0.13, P = 0.02). At zero change from BL for RNFL thickness (Y-intercept), retardance was reduced by 11% (95% confidence interval [CI]: -15.3% to -6.8%) and HFC by 21.5% (95% CI: -28.7% to -14.3%). Relative loss of RNFL thickness, retardance, and HFC (EG:CTL) were each related to axon loss (R2 = 0.66, P < 0.0001; R2 = 0.42, P < 0.0001; R2 = 0.42, P < 0.0001, respectively), but only retardance and HFC were significantly reduced at zero relative axon loss (Y-intercept; retardance: -9.4%, 95% CI: -15.5% to -3.4%; HFC: -10.9%, 95% CI: -18.6% to -3.2%; RNFL thickness: +1.8%, 95% CI: -4.9% to +5.4%). CONCLUSIONS Retinal nerve fiber layer retardance and RGC function exhibit progressive loss from baseline before any loss of RNFL thickness or orbital optic nerve axons occurs in NHP EG. These in vivo measures might serve as potential biomarkers of early-stage glaucomatous damage preceding axon loss and RGC death.
Collapse
|