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Ophthalmologica. Journal International... 2013The vitreous is a complex structure whose composition and appearance change with age. Anomalous adhesions between the posterior vitreous face and the retinal surface are... (Meta-Analysis)
Meta-Analysis Review
The vitreous is a complex structure whose composition and appearance change with age. Anomalous adhesions between the posterior vitreous face and the retinal surface are the cause of numerous vitreoretinal complications, while the presence of an intact posterior hyaloid provides a scaffold for vascular growth and anteroposterior traction. This review summarizes what is known about the biochemistry of the vitreous, the process of posterior vitreous detachment (PVD) development, and the available clinical approaches to examining the vitreous and its interface. A pooled analysis of studies looking at the presence of a complete, partial or absent PVD in a number of macular and retinal diseases allows us to establish odds ratios for these various states. From this emerge both protective and disease-associated states in conditions such as proliferative diabetic retinopathy, macular edema, and age-related macular degeneration. With the emergence of pharmacological means to separate the posterior hyaloid, a better understanding of the possible role of the vitreous in tractional syndromes is required.
Topics: Aging; Humans; Microscopy, Acoustic; Retina; Retinal Diseases; Tomography, Optical Coherence; Vitreous Body; Vitreous Detachment
PubMed: 23989078
DOI: 10.1159/000353447 -
Translational Vision Science &... May 2022To accurately evaluate pressure changes during vitrectomy in a rigid model of the vitreous chamber and to test the efficiency of the EVA phacovitrectomy system (Dutch...
PURPOSE
To accurately evaluate pressure changes during vitrectomy in a rigid model of the vitreous chamber and to test the efficiency of the EVA phacovitrectomy system (Dutch Ophthalmic Research Center) in terms of compensation of intraocular pressure variations.
METHODS
We tested 23-, 25-, and 27-gauge double-blade vitreous cutters in both vented global pressure control and automatic infusion compensation (AIC) modes in a vitreous chamber model, mimicking the real surgical procedure. Balanced salt solution and artificial vitreous, similar to the real vitreous body, were used. We tested both standard-flow (SF) and high-flow (HF) infusion systems, varying the infusion pressure between 20 and 40 mm Hg. In each experiment, flow rate was also measured.
RESULTS
Pressure drop was rapidly and efficiently compensated when 23- and 25-gauge cutters were used in AIC mode, with infusion pressures ranging between 30 and 55 mm Hg. The 27-gauge cutter was less efficient in compensating pressure variations. Pressure fluctuations related to the high-frequency motion of the cutter blade were small compared to the overall pressure variations. The use of the HF infusion system resulted in larger flow rates and lower pressure changes compared to the SF infusion system.
CONCLUSIONS
Despite the rigid material of the model, the present pressure measurements are in line with previous studies performed on porcine eye. The use of AIC mode compensates intraoperative pressure drops efficiently, with both 23- and 25-gauge cutters. The HF infusion system is more efficient than the SF infusion system.
TRANSLATIONAL RELEVANCE
The AIC infusion mode efficiently compensates intraoperative pressure drops, in both 23- and 25-gauge experimental vitrectomy. The HF infusion system resulted in larger flow rate and lower pressure changes.
Topics: Animals; Eye Diseases; Microsurgery; Swine; Tonometry, Ocular; Vitrectomy; Vitreous Body
PubMed: 35583885
DOI: 10.1167/tvst.11.5.21 -
BMC Ophthalmology Dec 2022This study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body (FCVB) in severe retinal detachment eyes.
BACKGROUND
This study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body (FCVB) in severe retinal detachment eyes.
METHODS
A retrospective study in retinal detachment eyes was performed at Shandong Provincial Hospital Affiliated to Shandong First Medical University. A standard three-port pars plana vitrectomy was performed, and the FCVB was triple folded and implanted into the vitreous cavity. The silicone oil (SO) was then injected into the capsule of the FCVB to support the retina and eye. During the follow-up period, The treated eyes were examined by ophthalmoscopy, fundus photography, and tonometry. B-scan ultrasonography, optical coherence tomography (OCT), and computed tomography (CT), were also performed.
RESULTS
From May 2020 to November 2021, 31 cases with severe retinal detachment were enrolled in the study. The postoperative follow-up time gradient ranged from 1 to 72 weeks, At various observation time points during the 72 weeks after surgery, The postoperative IOP was maintained at around 10 mmhg at various time points, with a slight decrease compared to the preoperative IOP (14.2 ± 4.6 mmHg n = 18), and was statistically significant. 9 of 31 patients had clear refractive media, both fundus and OCT showed retinal reattachment, OCT showed the 200 μm thick FCVB capsule support retina. The remaining 22 patients with unclear refractive media, B-scan showed arcuate hyperechoes in front of the retina. There was also no significant difference in visual acuity compared to preoperative. The FCVB was well positioned in the vitreous cavity, and no serious complications such as endophthalmitis, glaucoma, silicone oil emulsification, product exposure, or sympathetic uveitis were found.
CONCLUSIONS
FCVB has retinal support with certain ability to maintain IOP and eye morphology and avoid eye removal in patients with severe retinal detachment during the 72-week observation period.
Topics: Humans; Retinal Detachment; Vitreous Body; Silicone Oils; Retrospective Studies; Vitrectomy
PubMed: 36522622
DOI: 10.1186/s12886-022-02729-9 -
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 -
Indian Journal of Ophthalmology Mar 2015Primary vitreoretinal lymphoma (PVRL) is an uncommon, but potentially fatal intraocular malignancy, which may occur with or without primary central nervous system... (Review)
Review
Primary vitreoretinal lymphoma (PVRL) is an uncommon, but potentially fatal intraocular malignancy, which may occur with or without primary central nervous system lymphoma (PCNSL). Considered to be a subset of PCNSL, it is mostly of diffuse large B-cell type. The diagnosis of PVRL poses a challenge not only to the clinician, but also to the pathologist. Despite aggressive treatment with chemotherapy and/or radiotherapy, relapses or CNS involvement are common.
Topics: Humans; Lymphoma; Retinal Neoplasms; Vitreous Body
PubMed: 25971162
DOI: 10.4103/0301-4738.156903 -
AJNR. American Journal of Neuroradiology Jul 2022There is growing evidence of leakage of gadolinium in an impaired blood-retina barrier. We investigated gadolinium enhancement in different eye compartments and...
BACKGROUND AND PURPOSE
There is growing evidence of leakage of gadolinium in an impaired blood-retina barrier. We investigated gadolinium enhancement in different eye compartments and correlated the enhancement with specific ophthalmologic diseases.
MATERIALS AND METHODS
In a prospective clinical study (ClinicalTrials.gov Identifier: NCT05035251), 95 patients (63 with and 32 without ophthalmologic disease) were examined before and after gadolinium administration (20 and 120 minutes) with heavily T2-weighted FLAIR. The cohort was divided according to the location of pathology into anterior and posterior eye compartment groups. Relative signal intensity increase in the anterior eye chamber, vitreous body with retina, optic nerve sheath, and the Meckel cave was analyzed and correlated with the final clinical diagnosis.
RESULTS
In patients with a disorder in the anterior eye compartment, significant signal intensity increases were found in the central anterior eye chamber ( 20 minutes = .000, 120 minutes = .000), lateral anterior eye chamber ( 20 minutes = .001, 120 minutes = .005), and vitreous body with retina ( 20 minutes = .02) compared with the control group. Patients with pathologies in the posterior eye compartment showed higher signal intensity levels in the central anterior eye compartment ( 20 minutes = .041) and vitreous body with retina ( 120 minutes = .006).
CONCLUSIONS
Increased gadolinium enhancement was found in the central and lateral anterior eye compartments and the vitreous body with retina in patients with anterior eye compartment disorders 20 and 120 minutes after contrast application, suggesting impairment of the blood-aqueous barrier. In patients with a disorder in the posterior eye compartment, pathologic enhancement indicated disruption of the blood-retinal barrier that allows gadolinium to diffuse into the vitreous body with retina from posterior to anterior, opposite to the known physiologic glymphatic pathway.
Topics: Contrast Media; Gadolinium; Glymphatic System; Humans; Magnetic Resonance Imaging; Prospective Studies; Vitreous Body
PubMed: 35772805
DOI: 10.3174/ajnr.A7552 -
Eye (London, England) May 2016Floaters are a common ocular condition which form as a consequence of aging changes in the vitreous. Although in most patients the symptoms are minimal, they can cause... (Review)
Review
Floaters are a common ocular condition which form as a consequence of aging changes in the vitreous. Although in most patients the symptoms are minimal, they can cause significant impairment in vision-related quality of life in a small population of patients. Recently there has been an increase in awareness of the visual disability caused by floaters, and the evidence-base for treatment of this condition using small-gauge vitrectomy has increased. In this review, we define the term 'floaters' as symptomatic vitreous opacities (SVO). We suggest a classification dependent on the presence or absence of posterior vitreous detachment and discuss their pathogenesis and natural history. We review their impact on patients' quality of life related to visual function. We review the psychological factors that may have a role in some patients who appear to be affected by SVO to the extent that they pursue all options including surgery with all its attendant risks. We summarise the available evidence-base of treatment options available for SVO with special emphasis on the safety and efficacy of vitrectomy for this condition.
Topics: Evidence-Based Medicine; Eye Diseases; Humans; Quality of Life; Vitrectomy; Vitreous Body
PubMed: 26939559
DOI: 10.1038/eye.2016.30 -
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 -
International Ophthalmology Clinics 2014The identification of an infectious or noninfectious uveitis syndrome is important to determine the range of therapeutic and prognostic implications of that disease... (Review)
Review
The identification of an infectious or noninfectious uveitis syndrome is important to determine the range of therapeutic and prognostic implications of that disease entity. Diagnostic dilemmas arise with atypical history, atypical clinical presentations, inconclusive diagnostic workup, and persistent or worsened inflammation despite appropriate immunosuppression. More invasive intraocular testing is indicated in these situations particularly in infectious uveitis where a delay in treatment may result in worsening of the patient’s disease and a poor visual outcome. Laboratory analysis of vitreous fluid via diagnostic pars plana vitrectomy is an important technique in the diagnostic armamentarium, but the most important aspects of sample collection include rapid processing, close coordination with an ophthalmic pathology laboratory, and directed testing on this limited collected sample. Culture and staining has utility in bacterial, fungal, and nocardial infection. Polymerase chain reaction (PCR) analysis has shown promising results for bacterial endophthalmitis and infection with mycobacterium tuberculosis whereas PCR testing for viral retinitides and ocular toxoplasmosis has a more established role. Antibody testing is appropriate for toxoplasmosis and toxocariasis, and may be complementary to PCR for viral retinitis. Masquerade syndromes represent neoplastic conditions that clinically appear as infectious or inflammatory conditions and should be considered as part of the differential diagnosis. Diagnostic vitrectomy and chorioretinal biopsy are thus critical tools for the management of patients in whom an infectious etiology of uveitis is suspected.
Topics: Diagnosis, Differential; Diagnostic Techniques, Ophthalmological; Eye Infections; Humans; Reproducibility of Results; Uveitis; Vitrectomy; Vitreous Body
PubMed: 24613892
DOI: 10.1097/IIO.0000000000000017 -
Mediators of Inflammation 2012Non infectious vitreous inflammation is often vision threatening and can be associated with potentially life-threatening systemic conditions. Treatment is often... (Review)
Review
Non infectious vitreous inflammation is often vision threatening and can be associated with potentially life-threatening systemic conditions. Treatment is often challenging as it involves systemic medications that can be associated with adverse effects. The classes of drugs are ever expanding and include corticosteroids, antimetabolites, alkylating agents, T-cell and calcineurin agents, biologic agents, and interferons. Each class of systemic therapy for non-infectious vitreous inflammation is reviewed. We discuss the mechanisms of action, usual clinical dosages, the specific conditions that are treated, the adverse effects, and usual course of treatment for each class of therapy.
Topics: Adrenal Cortex Hormones; Antimetabolites; Biological Products; Humans; Inflammation; Interferons; Vitreous Body
PubMed: 23028205
DOI: 10.1155/2012/936721