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American Journal of Ophthalmology Apr 2021Myopic vitreopathy features precocious fibrous vitreous liquefaction and early posterior vitreous detachment (PVD). It is unclear whether visual function is affected by...
PURPOSE
Myopic vitreopathy features precocious fibrous vitreous liquefaction and early posterior vitreous detachment (PVD). It is unclear whether visual function is affected by myopic vitreopathy and PVD. This study assessed the relationships among axial length, structural vitreous density, PVD, and visual function.
DESIGN
Retrospective case-control study.
METHODS
Ultrasonography measurements were made of axial length, logMAR VA, contrast sensitivity function (CSF [Freiburg acuity contrast test]), and quantitative B-scan ultrasonography.
RESULTS
Seventy-nine subjects (45 men and 34 women; mean age: 49 ± 14 years) were analyzed. Axial lengths ranged from 22 to 29.2 mm (mean: 24.9 ± 1.8 mm; myopic eyes: 26.35 ± 1.35 mm; and nonmyopic eyes: 23.45 ± 0.75 mm; P < .001). With increasing axial length there was greater vitreous echodensity (R: 0.573; P < .01) and degradation in CSF (R: 0.611; P < .01). Subgroup analyses found that myopic eyes (>- 3 diopters) had 37% more vitreous echodensity than nonmyopic eyes (762 ± 198 arbitrary units [AU] vs. 557 ± 171 AU, respectively; P < .001) and that CSF was 53% worse in myopic eyes (3.30 ± 1.24 Weber index [%W]) than in nonmyopic eyes (2.16 ± .59 %W; P < .001). Myopic eyes with PVD had 33% greater vitreous echodensity (815 ± 217 AU; P < .001) and 62% degradation in CSF (3.63 ± 2.99 %W) compared to nonmyopic eyes with PVD (613 ± 159 AU; 2.24 ± 0.69 %W; P < .001, each). Limited vitrectomy was performed in 11 of 40 cases (27.5%), normalizing vitreous echodensity and CSF in each case.
CONCLUSIONS
Axial myopia is associated with increased fibrous vitreous liquefaction and echodensity, as well as profound degradation of CSF. PVD in myopic eyes is associated with even more structural and functional abnormalities, normalized by limited vitrectomy. These findings may explain some common complaints of myopic patients with respect to vision and quality of life.
Topics: Adult; Aged; Axial Length, Eye; Case-Control Studies; Contrast Sensitivity; Eye Diseases; Female; Humans; Male; Middle Aged; Myopia; Retrospective Studies; Tomography, Optical Coherence; Ultrasonography; Visual Acuity; Vitrectomy; Vitreous Body; Vitreous Detachment
PubMed: 32950508
DOI: 10.1016/j.ajo.2020.09.017 -
International Journal of Molecular... Feb 2021Photoreceptors are the light-sensing cells of the retina and the major cell type affected in most inherited retinal degenerations. Different metabolic pathways sustain...
Photoreceptors are the light-sensing cells of the retina and the major cell type affected in most inherited retinal degenerations. Different metabolic pathways sustain their high energetic demand in physiological conditions, particularly aerobic glycolysis. The principal metabolome of the mature retina has been studied, but only limited information is available on metabolic adaptations in response to key developmental events, such as eye opening. Moreover, dynamic metabolic changes due to retinal degeneration are not well understood. Here, we aimed to explore and map the ocular metabolic dynamics induced by eye opening in healthy (wild type) or -mutant (retinal degeneration 1, Rd1) mice, in which photoreceptors degenerate shortly after eye opening. To unravel metabolic differences emerging before and after eye opening under physiological and pathophysiological conditions, we performed nuclear magnetic resonance (NMR) spectroscopy-based metabolome analysis of wild type and Rd1 retina and vitreous/lens. We show that eye opening is accompanied by changes in the concentration of selected metabolites in the retina and by alterations in the vitreous/lens composition only in the retinal degeneration context. As such, we identify NAcetylaspartate as a potential novel vitreous/lens marker reflecting progressive retinal degeneration. Thus, our data can help elucidating mechanisms underlying key events in retinal physiology and reveal changes occurring in pathology, while highlighting the importance of the vitreous/lens in the characterization of retinal diseases.
Topics: Animals; Cyclic Nucleotide Phosphodiesterases, Type 6; Disease Models, Animal; Lens, Crystalline; Metabolome; Mice; Mutation; Retina; Retinal Degeneration; Vitreous Body
PubMed: 33652907
DOI: 10.3390/ijms22052345 -
Klinische Monatsblatter Fur... Jul 2020
Topics: Humans; Vision Disorders; Vitreous Body
PubMed: 32659840
DOI: 10.1055/a-1191-1137 -
Vestnik Oftalmologii 2024Diabetic vitreopapillary traction syndrome (VPT) is a variant of diabetic retinopathy (DR) that can lead to vision loss in advanced stages. This review reports on the... (Review)
Review
Diabetic vitreopapillary traction syndrome (VPT) is a variant of diabetic retinopathy (DR) that can lead to vision loss in advanced stages. This review reports on the biomechanics of the vitreous in the pathogenesis of proliferative DR, in particular diabetic VPT. The article analyzes and summarizes literature data, presents the views of different authors on this problem, and provides the results of Russian and foreign scientific research on this pathology. It is concluded that further research in this area can lead to a significant improvement in the results of therapy, timely diagnosis, and preservation of vision in patients with DR.
Topics: Humans; Diabetic Retinopathy; Vitreous Body; Biomechanical Phenomena; Syndrome; Vitreoretinopathy, Proliferative
PubMed: 38742502
DOI: 10.17116/oftalma202414002178 -
Retina (Philadelphia, Pa.) Feb 2022The causes of floaters include posterior vitreous detachment and fundus hemorrhage, both of which are risk factors for retinal tears. We observed the vitreous of...
PURPOSE
The causes of floaters include posterior vitreous detachment and fundus hemorrhage, both of which are risk factors for retinal tears. We observed the vitreous of patients with floaters using swept source optical coherence tomography.
METHODS
Fundus examination was performed, and the vitreous was observed using swept source optical coherence tomography in 202 eyes of 202 patients with floaters. Patients with uveitis, diabetic retinopathy, and other fundus diseases were excluded.
RESULTS
Swept source optical coherence tomography revealed posterior vitreous detachment in 145 of 202 eyes (71.8%) and dot reflex like stardust in the vitreous in 42 of 202 eyes (20.8%). Posterior vitreous detachment occurred in 35 of 42 eyes (83.3%) and 110 of 160 eyes (68.8%) in the stardust (+) and stardust (-) groups, respectively; a significant difference was observed (P <0.001). In the stardust (+) group, 11 of 42 eyes (26.2%) had retinal tears with posterior vitreous detachment and 21 of 42 eyes (50.0%) had fundus hemorrhage. Three of 160 eyes (1.9%) and 4 of 160 eyes (2.5%) in the stardust (-) group had retinal tears with posterior vitreous detachment and fundus hemorrhage, respectively. Both tears and fundus hemorrhage were more frequent in the stardust (+) group than in the stardust (-) group (P <0.001).
CONCLUSION
The stardust sign on swept source optical coherence tomography indicates the risk of retinal tear.
Topics: Adult; Aged; Aged, 80 and over; Female; Fundus Oculi; Humans; Male; Middle Aged; Prospective Studies; Retinal Perforations; Tomography, Optical Coherence; Vitreous Body; Vitreous Detachment; Young Adult
PubMed: 35050930
DOI: 10.1097/IAE.0000000000003317 -
Investigative Ophthalmology & Visual... Feb 2021Details of the posterior eye water dynamics are unclear. Aquaporin-4 (AQP4), a water channel, plays an important role in water dynamics in the central nervous system and...
PURPOSE
Details of the posterior eye water dynamics are unclear. Aquaporin-4 (AQP4), a water channel, plays an important role in water dynamics in the central nervous system and is also present in the ocular tissue. The purpose of this study was to reveal the role of AQP4 in the water dynamics of the posterior eye using in vivo JJ vicinal coupling proton exchange (JJVCPE) magnetic resonance imaging (MRI) of AQP4 knockout (KO) mice and their wild-type littermates (controls).
METHODS
JJVCPE MRI of the eye was performed on five AQP4 KO mice and seven control mice. We assessed the normalized signal intensities of a region of interest (ROI) set in the vitreous body after H217O administration. The results of the two groups were compared using a two-tailed Mann-Whitney U test.
RESULTS
A statistical analysis revealed that the normalized ROI signal intensities at the steady state were significantly lower (P = 0.010, <0.05) in the AQP4 KO mice (mean ± SD, 84.5% ± 2.7%) than the controls (mean ± SD, 88.8% ± 1.9%).
CONCLUSIONS
The present study using JJVCPE MRI of the eye demonstrated that retinal AQP4 has a potential role in the regulation of water inflow into the vitreous body. Absence of AQP4 in the KO mice probably induces lower water outflow from the vitreous body. Our results could help clarify the pathogenesis of various ocular diseases.
Topics: Animals; Aquaporin 4; Female; Magnetic Resonance Imaging; Male; Mice; Mice, Knockout; Models, Animal; Retina; Vitreous Body; Water
PubMed: 33599736
DOI: 10.1167/iovs.62.2.24 -
Experimental Eye Research Nov 2021Vitreous humor (VH) is not considered as a critical structure in the radiotherapy planning process. In the present study, an experimental animal model was performed to...
Vitreous humor (VH) is not considered as a critical structure in the radiotherapy planning process. In the present study, an experimental animal model was performed to examine the effects of radiotherapy on VH. The right eyes of twelve New Zealand rabbits were irradiated to 60 Gy in 3 fractions in accordance with the scheme used in the treatment of uveal melanoma in our clinic, and contralateral (left) eyes were considered as control. Weekly ophthalmologic examination was performed after irradiation, for three months. At the end of the third month, enucleation and vitreous collection were conducted. The vitreous samples were subjected to metabolomic analyses, ELISA analyses, viscosity measurements, and electron microscopic examination. In control and experimental vitreous samples, 275 different metabolites were identified, and 34 were found to differ significantly between groups. In multivariate analyzes, a clear distinction was observed between control and irradiated vitreous samples. Pathway analysis revealed that nine pathways were affected, and these pathways were mainly related to amino acid metabolism. A significant decrease was observed in the expressions of type II, V, and XI collagens in protein level in the ELISA. There was a non-significant decrease in type IX collagen and viscosity. Electron microscopic examination revealed disrupted collagen fibrillar ultra-structure and dispersed collagen fragments in the experimental vitreous. An intact vitreous is essential for a healthy eye. In this study, we observed that radiation causes changes in the vitreous that may have long-term consequences.
Topics: Animals; Body Fluids; Collagen; Male; Melanoma; Neoplasms, Experimental; Rabbits; Uveal Neoplasms; Vitreous Body
PubMed: 34688623
DOI: 10.1016/j.exer.2021.108802 -
Retina (Philadelphia, Pa.) Nov 2021Development of an automated method to quantify the count of vitreous hyperreflective foci (vHF) and intensity of vitreous haze in patients with uveitis by optical...
PURPOSE
Development of an automated method to quantify the count of vitreous hyperreflective foci (vHF) and intensity of vitreous haze in patients with uveitis by optical coherence tomography.
METHODS
A method based on deep learning to automatically segment the vHF, vitreous, and retinal pigment epithelium (RPE) in optical coherence tomography was developed using 1,058 scans from 88 optical coherence tomography volumes of 33 patients with intermediate, posterior or panuveitis. Based on segmented images, the vHF count and the relative intensity of vitreous to RPE (VIT/RPE-relative intensity) were quantified. Dice coefficient and intraclass correlation coefficient were calculated between ground truth and the trained network.
RESULTS
The segmented area of vHF, vitreous, and RPE by the deep learning-based model showed good agreement with the clinicians' results, yielding a Dice coefficient of 0.69, 0.99, and 0.88, respectively. The intraclass correlation coefficient of the vHF count and the VIT/RPE-relative intensity per scan was 0.99 and 1.00, respectively. In eyes of test set, changes in vHF and VIT/RPE-relative intensity during treatment did not show similar patterns.
CONCLUSION
Automated segmentation of the vHF, vitreous, and RPE in optical coherence tomography images of patients with uveitis was accomplished by a deep learning approach. The vHF count and VIT/RPE-relative intensity could be quantified with high reliability.
Topics: Female; Follow-Up Studies; Humans; Male; Middle Aged; Reproducibility of Results; Retinal Pigment Epithelium; Retrospective Studies; Tomography, Optical Coherence; Uveitis; Visual Acuity; Vitreous Body
PubMed: 33871400
DOI: 10.1097/IAE.0000000000003190 -
Vestnik Oftalmologii 2021This literature review provides modern information on the unique structure of the vitreous body, its functions, and its role in the pathogenesis of glaucoma, describes... (Review)
Review
This literature review provides modern information on the unique structure of the vitreous body, its functions, and its role in the pathogenesis of glaucoma, describes the features of the vitreous morphology and metabolism, notes its biomechanical and trophic functions, outlines its role in healthy hydrodynamics and hemodynamics of the eye, as well as in aqueous humor outflow. The review presents clinical observations on the association of pathological changes in the vitreous body with glaucoma development and examines the role of involutional changes in the vitreous in the pathogenesis of glaucoma. The article also discusses possible pathogenetic mechanisms of glaucoma development in terms of pathological changes in the vitreous.
Topics: Aqueous Humor; Glaucoma; Humans; Vitreous Body
PubMed: 34669344
DOI: 10.17116/oftalma2021137052323 -
International Ophthalmology Jun 2020To review the role of inflammatory mediators in proliferative vitreoretinopathy (PVR) development and the current treatment for PVR prevention. (Review)
Review
PURPOSE
To review the role of inflammatory mediators in proliferative vitreoretinopathy (PVR) development and the current treatment for PVR prevention.
METHODS
A PubMed search was carried out using these keywords "PVR," "inflammatory mediators," "growth factors," "cytokines" and "treatment." Studies regarding inflammatory mediators and PVR therapy were included and published up to December 2019.
RESULTS
Inflammatory mediators, namely growth factors and cytokines, have been implicated in the occurrence and development of PVR. Among various inflammatory mediators, transforming growth factor-β, platelet-derived growth factor, interleukin-6, interleukin-8 and tumor necrosis factor-α are considered to be particularly important. In this review, we focus on the hypothesis that growth factors and cytokines are involved in the development of PVR, and current treatment for the prevention of PVR.
CONCLUSION
We support the hypothesis that growth factors and cytokines may participate in the complex process of PVR development. More importantly, the identification of inflammatory mediators provides novel and efficacious therapeutic targets for the treatment of PVR.
Topics: Biomarkers; Humans; Inflammation Mediators; Vitreoretinopathy, Proliferative; Vitreous Body
PubMed: 32103371
DOI: 10.1007/s10792-020-01325-4