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Graefe's Archive For Clinical and... Jun 2023To compare macular damage in glaucomatous optic neuropathy (GON) and compressive optic neuropathy (CON) and assess its diagnostic accuracy in distinguishing between... (Observational Study)
Observational Study
PURPOSE
To compare macular damage in glaucomatous optic neuropathy (GON) and compressive optic neuropathy (CON) and assess its diagnostic accuracy in distinguishing between diseases.
METHODS
Observational, cross-sectional, single-center study. Patients with GON, CON, and healthy controls were included according to the eligibility criteria. An automated spectral-domain optical coherence tomography (SD-OCT) algorithm was used to segment the circumpapilary retinal nerve fiber layer (cpRNFL) and macula. The layer thickness was measured in each sector according to the Early Treatment Diabetic Retinopathy Study and the 6-sector Garway-Heath-based grids. Data was compared across all study groups, and the significance level was set at 0.05.
RESULTS
Seventy-five eyes of 75 participants, 25 with GON, 25 with CON, and 25 healthy controls (CG), were included. Macular thickness was diminished in the ganglion cell complex of GON and CON patients compared to CG (p<0.05). The best Garway-Heath-based grid parameters for distinguishing GON and CON were the nasal-inferior (NI) and nasal-superior sectors and the NI/temporal inferior (TI) damage ratios in the macular ganglion cell (mGCL) and inner plexiform (IPL) layers. Moreover, the combination of the NI sector and NI/TI damage ratios in both layers had higher discriminative power (AUC 0.909; 95% CI 0.830-0.988; p<0.001) than combining parameters in each layer separately.
CONCLUSION
Our findings suggest that the evaluation of macular segmented layers damage by SD-OCT may be a helpful add-on tool in the differential diagnosis between GON and CON.
Topics: Humans; Optic Disk; Cross-Sectional Studies; Retinal Ganglion Cells; Nerve Fibers; Optic Nerve Diseases; Glaucoma; Macula Lutea; Tomography, Optical Coherence
PubMed: 36625929
DOI: 10.1007/s00417-022-05962-6 -
Eye (London, England) Jul 2021Studying the biomechanical properties of biological tissue is crucial to improve our understanding of disease pathogenesis. The biomechanical characteristics of the... (Review)
Review
Studying the biomechanical properties of biological tissue is crucial to improve our understanding of disease pathogenesis. The biomechanical characteristics of the cornea, sclera and the optic nerve head have been well addressed with an extensive literature and an in-depth understanding of their significance whilst, in comparison, knowledge of the retina and choroid is relatively limited. Knowledge of these tissues is important not only to clarify the underlying pathogenesis of a wide variety of retinal and vitreoretinal diseases, including age-related macular degeneration, hereditary retinal dystrophies and vitreoretinal interface diseases but also to optimise the surgical handling of retinal tissues and, potentially, the design and properties of implantable retinal prostheses and subretinal therapies. Our aim with this article is to comprehensively review existing knowledge of the biomechanical properties of retina, internal limiting membrane (ILM) and the Bruch's membrane-choroidal complex (BMCC), highlighting the potential implications for clinical and surgical practice. Prior to this we review the testing methodologies that have been used both in vitro, and those starting to be used in vivo to aid understanding of their results and significance.
Topics: Bruch Membrane; Choroid; Humans; Macular Degeneration; Optic Disk; Retina
PubMed: 33649576
DOI: 10.1038/s41433-021-01437-w -
Experimental Eye Research Sep 2023The purpose was to quantify ocular dopamine in rabbits after stimulation of the optic nerve head with short-wavelength (blue) light to activate melanopsin expressed in...
The purpose was to quantify ocular dopamine in rabbits after stimulation of the optic nerve head with short-wavelength (blue) light to activate melanopsin expressed in the axons of intrinsically photosensitive retinal ganglion cells (ipRGCs). Dopamine levels in tears, aqueous humor, vitreous body, and retina (including choroid) were quantified after blue light stimulation of the optic nerve head of 15 rabbits with an optical fiber for 1 min, 10 min, or no stimulation (n = 5, each group). The left eye of all rabbits was operated on to introduce the optical fiber and stimulate the optic nerve, while the contralateral eye served as internal control. One minute of blue light stimulation significantly increased dopamine concentration in the vitreous body of the treated eyes compared to the contralateral ones (P = 0.015). Stimulation for 10 min significantly increased dopamine concentration in the vitreous body, as well as the aqueous humor (P < 0.05). Therefore, using an optical fiber approach to stimulate the optic nerve head with blue light significantly increased dopamine concentration in the aqueous humor and the vitreous body. This likely reflects an upregulation of retinal dopamine synthesis that could be attributed to ipRGC activation. However, the data provided in this study fell short of establishing a definitive link between dopamine release and ipRGC activation, mainly due to the lack of evidence supporting the expression of the melanopsin photopigment in the optic nerve.
Topics: Animals; Rabbits; Optic Disk; Dopamine; Retina; Retinal Ganglion Cells; Light; Rod Opsins; Photic Stimulation
PubMed: 37499737
DOI: 10.1016/j.exer.2023.109604 -
Investigative Ophthalmology & Visual... Mar 2020The purpose of this study was to investigate the characteristics of focal γ-zone parapapillary atrophy (focal γPPA) in patients with primary open-angle glaucoma (POAG)...
PURPOSE
The purpose of this study was to investigate the characteristics of focal γ-zone parapapillary atrophy (focal γPPA) in patients with primary open-angle glaucoma (POAG) using spectral-domain optical coherence tomography (SD-OCT).
METHODS
Three groups of POAG eyes (n = 214) were defined according to the circumferential extent of Bruch's membrane (BM) within the β-zone PPA, as follows: (1) no γPPA (intact BM; n = 81), (2) conventional γPPA (γPPA involving the fovea-BM-opening axis; n = 89), and (3) focal γPPA (γPPA not involving the fovea-BM-opening axis; n = 44). Clinical and ocular characteristics, including age, axial length (AXL), and focal lamina cribrosa (LC) defects were compared among the three groups.
RESULTS
The focal γPPA group was significantly older (60.6 ± 11.0 years) and had shorter AXL (24.10 ± 1.34 mm) than those of the conventional γPPA group (46.2 ± 13.8 years and 26.53 ± 1.61 mm, respectively; P < 0.001). These values of the focal γPPA group were similar to those of the no γPPA group (23.73 ± 0.97 mm for AXL and 64.0 ± 13.0 years for age). The focal γPPA group had a significantly higher prevalence of focal LC defects than did the other two groups (70.5% [31/44] for the focal γPPA group versus 46.1% [41/89] for the conventional γPPA group versus 37.0% [30/81] for the no γPPA group; P = 0.002).
CONCLUSIONS
Focal γPPA was differentiated from conventional γPPA by older age and shorter AXL. Further, focal γPPA was frequently accompanied by focal LC defects. Longitudinal studies elucidating whether focal LC defects and focal γPPA share common pathogenesis are warranted.
Topics: Adult; Age Factors; Aged; Axial Length, Eye; Bruch Membrane; Choroid; Female; Fovea Centralis; Glaucoma, Open-Angle; Humans; Male; Middle Aged; Optic Atrophy; Optic Disk; Tomography, Optical Coherence; Visual Fields
PubMed: 32176268
DOI: 10.1167/iovs.61.3.17 -
Scientific Reports Apr 2019This study was designed to evaluate if primary open angle glaucoma (POAG) and its severity are associated with the shape of the lamina cribrosa (LC) as measured by a...
This study was designed to evaluate if primary open angle glaucoma (POAG) and its severity are associated with the shape of the lamina cribrosa (LC) as measured by a global shape index (LC-GSI), or other indices of LC curvature or depth. Optical coherence tomography (OCT) scans of the optic nerve head (OHN) were obtained from subjects with POAG (n = 99) and non-glaucomatous controls (n = 76). ONH structures were delineated, the anterior LC morphology reconstructed in 3D, and the LC-GSI calculated (more negative values denote greater posterior concavity). Anterior LC depth and 2D-curvature were also measured. Severity of glaucoma was defined by the extent of visual field loss, based on the Hodapp-Parrish-Anderson grading. Linear regression analyses compared LC characteristics between controls, mild-moderate, and advanced POAG groups. After adjusting for age, gender, ethnicity, intraocular pressure, axial length and corneal curvature, the LC-GSI was most negative in the advanced POAG group (mean [standard error] = -0.34 [0.05]), followed by the mild-moderate POAG group (-0.31 [0.02]) and then controls (-0.23 [0.02], P = 0.01). There was also a significant trend of increasing LC depth and greater LC horizontal curvature with increasing severity of glaucoma (P = 0.04 and 0.02, respectively). Therefore, with more severe glaucoma, the LC-GSI was increasingly more negative, and the anterior LC depth and curvature greater. These observations collectively correspond to greater cupping of the ONH at the level of the LC. As the LC-GSI describes the 3D anterior LC morphology, its potential usage may be complementary to existing ONH parameters measured on OCT.
Topics: Aged; Cross-Sectional Studies; Female; Glaucoma; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Linear Models; Male; Middle Aged; Optic Disk; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 31036869
DOI: 10.1038/s41598-019-42649-1 -
Wavefront aberrations and retinal image quality in different lenticular opacity types and densities.Scientific Reports Nov 2017To investigate wavefront aberrations in the entire eye and in the internal optics (lens) and retinal image qualities according to different lenticular opacity types and... (Clinical Trial)
Clinical Trial
To investigate wavefront aberrations in the entire eye and in the internal optics (lens) and retinal image qualities according to different lenticular opacity types and densities. Forty-one eyes with nuclear cataract, 33 eyes with cortical cataract, and 29 eyes with posterior subcapsular cataract were examined. In each group, wavefront aberrations in the entire eye and in the internal optics and retinal image quality were measured using a raytracing aberrometer. Eyes with cortical cataracts showed significantly higher coma-like aberrations compared to the other two groups in both entire eye and internal optic aberrations (P = 0.012 and P = 0.007, respectively). Eyes with nuclear cataract had lower spherical-like aberrations than the other two groups in both entire eye and internal optics aberrations (P < 0.001 and P < 0.001, respectively). In the nuclear cataract group, nuclear lens density was negatively correlated with internal spherical aberrations (r = -0.527, P = 0.005). Wavefront technology is useful for objective and quantitative analysis of retinal image quality deterioration in eyes with different early lenticular opacity types and densities. Understanding the wavefront optical properties of different crystalline lens opacities may help ophthalmic surgeons determine the optimal time to perform cataract surgery.
Topics: Aged; Cataract; Corneal Topography; Female; Humans; Lens, Crystalline; Male; Middle Aged; Retina
PubMed: 29127310
DOI: 10.1038/s41598-017-15245-4 -
Scientific Reports Jun 2022We present a compact multi-modal and multi-scale retinal imaging instrument with an angiographic functional extension for clinical use. The system integrates scanning...
We present a compact multi-modal and multi-scale retinal imaging instrument with an angiographic functional extension for clinical use. The system integrates scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT) and OCT angiography (OCTA) imaging modalities and provides multi-scale fields of view. For high resolution, and high lateral resolution in particular, cellular imaging correction of aberrations by adaptive optics (AO) is employed. The entire instrument has a compact design and the scanning head is mounted on motorized translation stages that enable 3D self-alignment with respect to the subject's eye by tracking the pupil position. Retinal tracking, based on the information provided by SLO, is incorporated in the instrument to compensate for retinal motion during OCT imaging. The imaging capabilities of the multi-modal and multi-scale instrument were tested by imaging healthy volunteers and patients.
Topics: Humans; Ophthalmoscopy; Optics and Photonics; Pupil; Retina; Tomography, Optical Coherence
PubMed: 35688890
DOI: 10.1038/s41598-022-13631-1 -
Acta Ophthalmologica Sep 2022To map the morphology of the retina and optic disc in adolescents with surgically treated hydrocephalus (HC) in infancy and to compare the results with healthy controls.
PURPOSE
To map the morphology of the retina and optic disc in adolescents with surgically treated hydrocephalus (HC) in infancy and to compare the results with healthy controls.
METHODS
The study comprised 26 adolescents (16 male, mean age 15 years) with HC and 31 sex- and aged-matched controls. The following optical coherence tomography (OCT) parameters were obtained: macular retinal thickness (MRT) and volume (MRV), thickness of the macular and peripapillary retinal nerve fibre layer (ppRNFL), and area of the optic disc, cup and rim.
RESULTS
The MRT was thinner amongst those with HC compared with controls (right eye (RE) 262.2 ± 15.3 and 275.8 ± 15.1 μm; p = 0.0051), and the MRV was smaller (RE 7.37 ± 0.36 and 7.83 ± 0.35 mm ; p = 0.0002). The HC group showed a thinner ppRNFL (RE 88.3 ± 14.9 and 103.5 ± 8.1 μm; p = 0.0002) but a thicker central macular RNFL (RE 11.6 ± 10.4 and 2.07 ± 3.00 μm; p = <0.0001) and foveal minimum (RE 211.1 ± 32.0 and 186.3 ± 15.9 μm; p = 0.0013). Optic disc variables showed no difference between groups. Correlations were found in the HC group between best corrected visual acuity (expressed in logMAR) and ppRNFL (RE r = -0.56, p = 0.018), and disc area (RE r = -0.52, p = 0.033).
CONCLUSION
Thinner ppRNFL and MRT and smaller MRV were found in adolescents with surgically treated HC in infancy compared with controls. In contrast, the central macular RNFL and foveal minimum were thicker. Further studies are required to evaluate the diagnostic value of OCT to indicate increased intracranial pressure timely and follow-up in individuals with surgically treated HC.
Topics: Adolescent; Aged; Humans; Hydrocephalus; Male; Nerve Fibers; Optic Disk; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35507694
DOI: 10.1111/aos.15162 -
Indian Journal of Ophthalmology Feb 2021The objective of this study was to identify the diagnostic features of optic nerve head melanocytoma (ONH-MCT) on spectral domain optical coherence tomography (SD OCT)...
PURPOSE
The objective of this study was to identify the diagnostic features of optic nerve head melanocytoma (ONH-MCT) on spectral domain optical coherence tomography (SD OCT) and OCT angiography (OCT-A).
METHODS
Retrospective study of 11 patients for their demographic, clinical features and imaging including SD OCT (tumour location, extent and interface) and OCT-A (surface and intrinsic vascularity) were reviewed. Flow rate percentage (FR %) was calculated over the lesion and compared to fellow eye and similar pigmented lesions.
RESULTS
The average age was 52.8 ± 10.9 years. ONH-MCT tumors occupied 3-tissue spaces- optic disc (n = 2), retinal layer (n = 5) and retina-choroidal layers (n = 4). SD OCT (11 eyes) showed elevated hyper reflective disorganized retinal layers with posterior shadowing (9 eyes) and hyper reflective dots within the tumor (all eyes). Microvascular features on OCT-A (8 eyes) in radial peripapillary capillary slab showed surface vascularization (7 eyes) and intrinsic vascularity in choroidal slab (8 eyes) with surrounding hypo reflective boundary. The mean FR % was higher at 65.1 ± 3.77% (CI: 61.9-68.2) compared to mean FR at 60.4 ± 1.06% (CI: 59.5-61.2) in the fellow eye (p = 0.01). Comparison with nevus and melanoma SD OCT showed a high reflective choroidal layer with normal or irregular outer retinal layers respectively; OCT-A showed hypo reflective area at the center with hyper reflective boundary and iso reflective area at center with hyper reflective boundary respectively.
CONCLUSION
SD OCT and OCT-A features may help to differentiate ONH-MCT from clinically similar looking pigmented lesions like nevus and melanoma.
Topics: Adult; Choroid; Humans; Middle Aged; Optic Disk; Retrospective Studies; Skin Neoplasms; Tomography, Optical Coherence
PubMed: 33463586
DOI: 10.4103/ijo.IJO_710_20 -
Proceedings of the National Academy of... Nov 2021Retinitis pigmentosa (RP) is the most common group of inherited retinal degenerative diseases, whose most debilitating phase is cone photoreceptor death. Perimetric and...
Retinitis pigmentosa (RP) is the most common group of inherited retinal degenerative diseases, whose most debilitating phase is cone photoreceptor death. Perimetric and electroretinographic methods are the gold standards for diagnosing and monitoring RP and assessing cone function. However, these methods lack the spatial resolution and sensitivity to assess disease progression at the level of individual photoreceptor cells, where the disease originates and whose degradation causes vision loss. High-resolution retinal imaging methods permit visualization of human cone cells in vivo but have only recently achieved sufficient sensitivity to observe their function as manifested in the cone optoretinogram. By imaging with phase-sensitive adaptive optics optical coherence tomography, we identify a biomarker in the cone optoretinogram that characterizes individual cone dysfunction by stimulating cone cells with flashes of light and measuring nanometer-scale changes in their outer segments. We find that cone optoretinographic responses decrease with increasing RP severity and that even in areas where cone density appears normal, cones can respond differently than those in controls. Unexpectedly, in the most severely diseased patches examined, we find isolated cones that respond normally. Short-wavelength-sensitive cones are found to be more vulnerable to RP than medium- and long-wavelength-sensitive cones. We find that decreases in cone response and cone outer-segment length arise earlier in RP than changes in cone density but that decreases in response and length are not necessarily correlated within single cones.
Topics: Electroretinography; Eye Proteins; Humans; Ophthalmoscopy; Retina; Retinal Cone Photoreceptor Cells; Retinitis Pigmentosa
PubMed: 34795055
DOI: 10.1073/pnas.2107444118