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Asia-Pacific Journal of Ophthalmology... Nov 2020Chromovitrectomy, the intraocular application of dyes to assist visualization of preretinal tissues during vitreoretinal surgery, was introduced to avoid ocular... (Review)
Review
Chromovitrectomy, the intraocular application of dyes to assist visualization of preretinal tissues during vitreoretinal surgery, was introduced to avoid ocular complications related to internal limiting membrane peeling, inadequate removal of the vitreous, and incomplete removal of epiretinal membranes. Since 2000, chromovitrectomy has become a popular approach among vitreoretinal specialists. The first vital dye used in chromovitrectomy, indocyanine green, facilitated identification of the fine and transparent internal limiting membrane. Following indocyanine green, trypan blue was introduced to identify epiretinal membranes, and triamcinolone acetonide stained the vitreous well. Recently, additional natural dyes such as lutein and anthocyanin from the açaí fruit have been proposed for intraocular application during vitrectomy. The main goal of this review was to study the role of vital stains in chromovitrectomy and report the latest findings in the literature.
Topics: Coloring Agents; Epiretinal Membrane; Humans; Indocyanine Green; Ophthalmologic Surgical Procedures; Staining and Labeling; Trypan Blue; Vitrectomy; Vitreoretinal Surgery; Vitreous Body
PubMed: 33252365
DOI: 10.1097/APO.0000000000000344 -
Journal of the Mechanical Behavior of... Oct 2022Vitreoretinal mechanics plays an important role in retinal trauma and many sight-threatening diseases. In age-related pathologies, such as posterior vitreous detachment... (Review)
Review
Vitreoretinal mechanics plays an important role in retinal trauma and many sight-threatening diseases. In age-related pathologies, such as posterior vitreous detachment and vitreomacular traction, lingering vitreoretinal adhesions can lead to macular holes, epiretinal membranes, retinal tears and detachment. In age-related macular degeneration, vitreoretinal traction has been implicated in the acceleration of the disease due to the stimulation of vascular growth factors. Despite this strong mechanobiological influence on trauma and disease in the eye, fundamental understanding of the mechanics at the vitreoretinal interface is limited. Clarification of adhesion mechanisms and the role of vitreoretinal mechanics in healthy eyes and disease is necessary to develop innovative treatments for these pathologies. In this review, we evaluate the existing literature on the structure and function of the vitreoretinal interface to gain insight into age- and region-dependent mechanisms of vitreoretinal adhesion. We explore the role of vitreoretinal adhesion in ocular pathologies to identify knowledge gaps and future research areas. Finally, we recommend future mechanics-based studies to address the critical needs in the field, increase fundamental understanding of vitreoretinal mechanisms and disease, and inform disease treatments.
Topics: Humans; Retinal Perforations; Tissue Adhesions; Vitreous Body
PubMed: 35963021
DOI: 10.1016/j.jmbbm.2022.105399 -
Investigative Ophthalmology & Visual... Dec 2023Vitreoretinal lymphoma is a high-grade malignant non-Hodgkin lymphoma with poor prognosis. The objective of this study was to elucidate the proteome profile of the...
PURPOSE
Vitreoretinal lymphoma is a high-grade malignant non-Hodgkin lymphoma with poor prognosis. The objective of this study was to elucidate the proteome profile of the vitreous in patients with vitreoretinal lymphoma (VRL), aiming to advance understanding of the pathophysiology of VRL.
METHODS
Comprehensive proteomic analyses of vitreous humor using liquid chromatography with tandem mass spectrometry were performed for 10 patients with VRL, 10 control patients with idiopathic epiretinal membrane or macular hole, and 10 patients with ocular sarcoidosis. Differentially expressed proteins (DEPs) were identified by comparing VRL with controls and sarcoidosis, and functional pathway analysis was performed. Finally, vitreous concentrations of representative DEPs that were significantly upregulated in proteomics study were measured by ELISA using a separate cohort.
RESULTS
In total, 1594 proteins were identified in the vitreous humor of VRL, control, and sarcoidosis samples. Also, 282 DEPs were detected in VRL, 249 upregulated and 33 downregulated, compared with controls. Enrichment pathway analysis showed alterations in proteasome-related pathways. Compared to controls and sarcoidosis, 14 DEPs in VRL showed significant upregulation. In the validation study, ELISA confirmed significantly higher vitreous concentrations of PSAT1, YWHAG, and 20S/26S proteasome complex in VRL compared with controls and sarcoidosis. Among the upregulated DEPs, vitreous PITHD1 and NCSTN concentrations correlated positively with vitreous IL-10 concentrations.
CONCLUSIONS
This study highlights aberrations in protein expression pattern in the vitreous of patients with VRL. The DEPs identified in this study may play pivotal roles in VRL pathogenesis, providing insights to enhance understanding of VRL pathophysiology and contribute to the development of VRL biomarkers.
Topics: Humans; Vitreous Body; Retinal Neoplasms; Proteomics; Lymphoma, Non-Hodgkin; Sarcoidosis; Proteins; 14-3-3 Proteins
PubMed: 38038618
DOI: 10.1167/iovs.64.15.2 -
Cellular and Molecular Life Sciences :... Dec 2022Proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR), and neovascular age-related macular degeneration (nAMD) are among the leading causes of... (Review)
Review
Proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR), and neovascular age-related macular degeneration (nAMD) are among the leading causes of blindness. Due to the multifactorial nature of these vitreoretinal diseases, omics approaches are essential for a deeper understanding of the pathophysiologic processes underlying the evolution to a proliferative or neovascular etiology, in which patients suffer from an abrupt loss of vision. For many years, it was thought that the function of the vitreous was merely structural, supporting and protecting the surrounding ocular tissues. Proteomics studies proved that vitreous is more complex and biologically active than initially thought, and its changes reflect the physiological and pathological state of the eye. The vitreous is the scenario of a complex interplay between inflammation, fibrosis, oxidative stress, neurodegeneration, and extracellular matrix remodeling. Vitreous proteome not only reflects the pathological events that occur in the retina, but the changes in the vitreous itself play a central role in the onset and progression of vitreoretinal diseases. Therefore, this review offers an overview of the studies on the vitreous proteome that could help to elucidate some of the pathological mechanisms underlying proliferative and/or neovascular vitreoretinal diseases and to find new potential pharmaceutical targets.
Topics: Humans; Vitreous Body; Proteome; Vitreoretinopathy, Proliferative; Retina; Diabetic Retinopathy
PubMed: 36585968
DOI: 10.1007/s00018-022-04670-y -
Frontiers in Immunology 2023Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are leading causes of visual impairment and blindness in people aged 50 years or older in...
Proteomics profiling of vitreous humor reveals complement and coagulation components, adhesion factors, and neurodegeneration markers as discriminatory biomarkers of vitreoretinal eye diseases.
INTRODUCTION
Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are leading causes of visual impairment and blindness in people aged 50 years or older in middle-income and industrialized countries. Anti-VEGF therapies have improved the management of neovascular AMD (nAMD) and proliferative DR (PDR), no treatment options exist for the highly prevalent dry form of AMD.
METHODS
To unravel the biological processes underlying these pathologies and to find new potential biomarkers, a label-free quantitative (LFQ) method was applied to analyze the vitreous proteome in PDR (n=4), AMD (n=4) compared to idiopathic epiretinal membranes (ERM) (n=4).
RESULTS AND DISCUSSION
Post-hoc tests revealed 96 proteins capable of differentiating among the different groups, whereas 118 proteins were found differentially regulated in PDR compared to ERM and 95 proteins in PDR compared to dry AMD. Pathway analysis indicates that mediators of complement, coagulation cascades and acute phase responses are enriched in PDR vitreous, whilst proteins highly correlated to the extracellular matrix (ECM) organization, platelet degranulation, lysosomal degradation, cell adhesion, and central nervous system development were found underexpressed. According to these results, 35 proteins were selected and monitored by MRM (multiple reaction monitoring) in a larger cohort of patients with ERM (n=21), DR/PDR (n=20), AMD (n=11), and retinal detachment (n=13). Of these, 26 proteins could differentiate between these vitreoretinal diseases. Based on Partial least squares discriminant and multivariate exploratory receiver operating characteristic (ROC) analyses, a panel of 15 discriminatory biomarkers was defined, which includes complement and coagulation components (complement C2 and prothrombin), acute-phase mediators (alpha-1-antichymotrypsin), adhesion molecules (e.g., myocilin, galectin-3-binding protein), ECM components (opticin), and neurodegeneration biomarkers (beta-amyloid, amyloid-like protein 2).
Topics: Humans; Vitreous Body; Angiogenesis Inhibitors; Proteomics; Vascular Endothelial Growth Factor A; Visual Acuity; Wet Macular Degeneration; Complement System Proteins; Biomarkers; Diabetic Retinopathy; Epiretinal Membrane
PubMed: 36875133
DOI: 10.3389/fimmu.2023.1107295 -
Journal of AAPOS : the Official... Feb 2022To compare vitreous opacity density in infants born at term and in infants born prematurely using an investigational handheld swept-source optical coherence tomography...
PURPOSE
To compare vitreous opacity density in infants born at term and in infants born prematurely using an investigational handheld swept-source optical coherence tomography (SS-OCT).
METHODS
Infants born at term underwent imaging once between 12 and 48 hours after birth; infants born prematurely were imaged at each routine retinopathy of prematurity (ROP) examination. Three masked, trained graders analyzed images. Semiautomated methods were used to quantify vitreous opacity density, which was correlated with ROP severity based on indirect ophthalmoscopy, other SS-OCT findings, and medical comorbidities.
RESULTS
Between April 2018 and June 2019, 251 SS-OCT imaging sessions were performed on 78 infants (49% female; 36% preterm, with mean birth weight of 1018 ± 338 g and gestational age of 28.6 ± 3.2 weeks). All SS-OCT sessions produced images of adequate quality. Punctate vitreous opacities were present in 25 of 28 term infants (89%) and 41 of 50 premature infants (82%). Dice coefficient and F1 scores for intergrader agreement were 0.99 ± 0.03 and 0.77 ± 0.31, respectively. Vitreous opacity density was 0.118 ± 0.187 in prematurely born infants and 0.031 ± 0.118 in infants born at term (P = 0.009). In the former, vitreous opacity density was associated with ROP zone (P = 0.044) and stage (P = 0.031), intraventricular hemorrhage (P = 0.028), subchorionic hemorrhage (P = 0.026), and African American race (P = 0.023). In the latter, vitreous opacity density was associated with maternal diabetes (P = 0.049).
CONCLUSIONS
Our investigational handheld SS-OCT achieved high-quality vitreoretinal images. In our study cohort, punctate vitreous opacities were a frequent finding in infants born at term and those born prematurely, with increased density in those born prematurely, particularly those with severe ROP.
Topics: Female; Gestational Age; Humans; Infant; Infant, Newborn; Infant, Premature; Male; Ophthalmoscopy; Retinopathy of Prematurity; Tomography, Optical Coherence; Vitreous Body
PubMed: 34973449
DOI: 10.1016/j.jaapos.2021.09.007 -
Investigative Ophthalmology & Visual... Feb 2022To determine the differences of metabolites and metabolic pathways between patients with proliferative diabetic retinopathy (PDR) and without diabetes (nondiabetic... (Comparative Study)
Comparative Study
PURPOSE
To determine the differences of metabolites and metabolic pathways between patients with proliferative diabetic retinopathy (PDR) and without diabetes (nondiabetic controls) in plasma and vitreous, respectively, and to characterize the relationship between plasma and vitreous metabolic profiles.
METHODS
Liquid chromatography/tandem mass spectrometry technology was performed to distinct metabolite profiles of plasma and vitreous. A total of 139 plasma samples from 88 patients with PDR and 51 nondiabetic controls, as well as 74 vitreous samples from 51 patients with PDR and 23 nondiabetic controls, were screened. Pathway analysis was performed using MetaboAnalyst 5.0. Pearson correlation analysis was used to investigate the correlation of metabolites in vitreous and plasma.
RESULTS
After adjusting for age, fasting blood glucose, and urea, in vitreous metabolomes, a total of 76 features distinguished patients with PDR from controls. Fifteen differential metabolites were found in plasma metabolites. Pantothenate and CoA biosynthesis was the common metabolic pathway altered in both plasma and vitreous. Aromatic amino acid metabolism pathways were dysregulated in vitreous of PDR. For four metabolic features, there were positive correlations between vitreous and plasma.
CONCLUSIONS
Despite great differences between the metabolic profiles of plasma and vitreous in PDR cases, there are also similarities in the change of metabolites and metabolic pathways. Exploring the relationship of metabolomics between vitreous and plasma may help provide new understanding of the mechanism of PDR.
Topics: Adult; Aged; Blood Glucose; Chromatography, Liquid; Diabetic Retinopathy; Eye Proteins; Female; Humans; Male; Metabolome; Metabolomics; Middle Aged; Plasma; Tandem Mass Spectrometry; Urea; Vitreous Body
PubMed: 35133401
DOI: 10.1167/iovs.63.2.17 -
Bioelectromagnetics Feb 2022Vitreous "floaters" are a common entoptic phenomenon that can result in significant reduction in quality of life in a proportion of sufferers. The authors use a...
Vitreous "floaters" are a common entoptic phenomenon that can result in significant reduction in quality of life in a proportion of sufferers. The authors use a computational mathematical model based on Fourier optics and reflection and transmission coefficients calculated for a planar type II collagen opacity suspended in aqueous to show that floaters are perceived by the patient through interference effects that result in significant variations in intensity on the retina when viewing a constant brightness surface. The model also predicts that backscattered intensity from floaters is ten thousand to one million times lower than the variations in intensity produced on the retina, which demonstrates that the visible effects of floaters for the patient can be highly significant, whereas clinical observation of the vitreous may be entirely unremarkable. Importantly, the results also demonstrate that floaters do not need to be opaque to cause symptoms, with only small differences in refractive index between the floater material and the surrounding vitreous needed to produce significant optical effects. The model predicts that pupil size is an important factor in determining the severity of symptoms from floaters, with constricted pupils giving much greater effect than dilated pupils. Finally, the authors' model predicts that floaters degrade contrast sensitivity function, with greatest degradation occurring in the 5-40 cycles per degree spatial frequency range and that the effects of shadowing caused by floaters are very strongly correlated to the predicted degradation of contrast sensitivity function. Bioelectromagnetics. 43:90-105, 2022. © 2021 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.
Topics: Eye Diseases; Humans; Quality of Life; Retina; Vitreous Body
PubMed: 34969150
DOI: 10.1002/bem.22386 -
PloS One 2022Vitreous humor is a complex biofluid whose composition determines its structure and function. Vitreous viscosity will affect the delivery, distribution, and half-life of...
PURPOSE
Vitreous humor is a complex biofluid whose composition determines its structure and function. Vitreous viscosity will affect the delivery, distribution, and half-life of intraocular drugs, and key physiological molecules. The central pig vitreous is thought to closely match human vitreous viscosity. Diffusion is inversely related to viscosity, and diffusion is of fundamental importance for all biochemical reactions. Fluorescence Recovery After Photobleaching (FRAP) may provide a novel means of measuring intravitreal diffusion that could be applied to drugs and physiological macromolecules. It would also provide information about vitreous viscosity, which is relevant to drug elimination, and delivery.
METHODS
Vitreous viscosity and intravitreal macromolecular diffusion of fluorescently labelled macromolecules were investigated in porcine eyes using fluorescence recovery after photobleaching (FRAP). Fluorescein isothiocyanate conjugated (FITC) dextrans and ficolls of varying molecular weights (MWs), and FITC-bovine serum albumin (BSA) were employed using FRAP bleach areas of different diameters.
RESULTS
The mean (±standard deviation) viscosity of porcine vitreous using dextran, ficoll and BSA were 3.54 ± 1.40, 2.86 ± 1.13 and 4.54 ± 0.13 cP respectively, with an average of 3.65 ± 0.60 cP.
CONCLUSIONS
FRAP is a feasible and practical optical method to quantify the diffusion of macromolecules through vitreous.
Topics: Animals; Bevacizumab; Dextrans; Diffusion; Ficoll; Fluorescein-5-isothiocyanate; Fluorescence Recovery After Photobleaching; Ranibizumab; Receptors, Vascular Endothelial Growth Factor; Recombinant Fusion Proteins; Serum Albumin, Bovine; Swine; Viscosity; Vitreous Body
PubMed: 35143514
DOI: 10.1371/journal.pone.0261925 -
BMJ Case Reports Feb 2021We describe a case of endogenous endophthalmitis in an elderly man caused by An 88-year-old male patient with diabetes with iron deficiency anaemia and history of...
We describe a case of endogenous endophthalmitis in an elderly man caused by An 88-year-old male patient with diabetes with iron deficiency anaemia and history of transcatheter aortic valve implantation presented with an insidious clinical picture of atraumatic endophthalmitis. No internal or external source could be identified. Diagnostic and therapeutic vitrectomy revealed papillomacular abscess and vitreous fluids grew Despite lack of an identifiable source of infection, a high index of suspicion for atypical presentations is required in patients with multiple comorbidities that could weaken their immune system towards opportunistic infections. Early detection, microbiological evaluation and prompt treatment are critical to avoid disastrous outcomes. While has been implicated in cases of exogenous endophthalmitis, this is the first reported case of endogenous endophthalmitis due to .
Topics: Abscess; Aged, 80 and over; Anti-Bacterial Agents; Ceftazidime; Endophthalmitis; Eye Infections, Bacterial; Humans; Male; Streptococcus salivarius; Ultrasonography; Vancomycin; Vitrectomy; Vitreous Body
PubMed: 33541999
DOI: 10.1136/bcr-2020-239299