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Survey of Ophthalmology 2016Vitreous is a hydrated extracellular matrix comprised primarily of water, collagens, and hyaluronan organized into a homogeneously transparent gel. Gel liquefaction... (Review)
Review
Vitreous is a hydrated extracellular matrix comprised primarily of water, collagens, and hyaluronan organized into a homogeneously transparent gel. Gel liquefaction results from molecular alterations with dissociation of collagen from hyaluronan and aggregation of collagen fibrils forming fibers that cause light scattering and hence symptomatic floaters, especially in myopia. With aging, gel liquefaction and weakened vitreoretinal adhesion result in posterior vitreous detachment, the most common cause of primary symptomatic floaters arising from the dense collagen matrix of the posterior vitreous cortex. Recent studies indicate that symptomatic floaters are not only more prevalent, but also have a negative impact on the quality of life that is greater than previously appreciated. We review the literature concerning management of symptomatic vitreous floaters, currently either with observation, vitrectomy, or Nd:YAG laser. Published evidence is consistent with a low-risk profile and excellent success rate for floater vitrectomy, particularly with sutureless small gauge instruments and a limited core vitrectomy without PVD induction. Nd:YAG laser treatment of floaters, reported less commonly, claims resolution of floaters ranging between 0% and 100%; however, both peer-reviewed literature and assertions on web-based nonpeer-reviewed laser vitreolysis sites remain to be substantiated, and at present only vitrectomy has proven value. Prospective studies using objective, quantitative outcome measures are required to assess the relative efficacy and safety of these two procedures as well as new therapies such as pharmacologic vitreolysis.
Topics: Eye Diseases; Humans; Laser Therapy; Lasers, Solid-State; Observation; Vitrectomy; Vitreous Body
PubMed: 26679984
DOI: 10.1016/j.survophthal.2015.11.008 -
Blood Oct 2021Primary vitreoretinal lymphoma (PVRL) is a rare form of primary central nervous system (CNS) lymphoma (PCNSL) arising in the intraocular compartment without brain... (Review)
Review
Primary vitreoretinal lymphoma (PVRL) is a rare form of primary central nervous system (CNS) lymphoma (PCNSL) arising in the intraocular compartment without brain involvement. Despite its apparent indolent clinical course, PVRL can cause permanent vision loss and CNS relapse, the major cause of death in patients with PVRL. The pathophysiology of PVRL is unknown. As in PCNSL, the transformation of the tumor cells likely originates outside the CNS, before the cells migrate to the eye and proliferate within an immune-permissive microenvironment. PVRL exhibits a biased immunoglobulin repertoire, suggesting underlying antigen selection. The diagnosis remains challenging, requiring close coordination between ophthalmologists and cytologists. Because of their rarity and fragility in the vitreous, lymphoma cells cannot always be identified. Interleukin levels, molecular biology, and imaging are used in combination with clinical ophthalmological examination to support the diagnosis of PVRL. Multi-institutional prospective studies are urgently needed to validate the equivocal conclusions regarding treatments drawn from heterogeneous retrospective or small cohort studies. Intravitreal injection of methotrexate or rituximab or local radiotherapy is effective at clearing tumor cells within the eyes but does not prevent CNS relapse. Systemic treatment based on high-dose methotrexate chemotherapy, with or without local treatment, might reduce this risk. At relapse, intensive consolidation chemotherapy followed by stem cell transplantation can be considered. Single-agent ibrutinib, lenalidomide, and temozolomide treatments are effective in patients with relapsed PVRL and should be tested as first-line treatments. Therapeutic response assessment based on clinical examination is improved by measuring cytokine levels but still needs to be refined.
Topics: Animals; Disease Management; Humans; Retina; Retinal Neoplasms; Vitreous Body
PubMed: 34036310
DOI: 10.1182/blood.2020008235 -
Archivos de La Sociedad Espanola de... Oct 2019The Berger's space (BS) is a space located between the posterior capsule of the lens and the anterior hyaloid of the vitreous, structures that adhere in a circular...
INTRODUCTION AND OBJECTIVE
The Berger's space (BS) is a space located between the posterior capsule of the lens and the anterior hyaloid of the vitreous, structures that adhere in a circular manner by means of the Wieger ligament, for which the outer limit is defined by Egger's line. The aim of this article is to perform a review of the BS, as well as to present three cases in which this BS could be demonstrated by optical coherence tomography (OCT).
MATERIAL AND METHOD
A total of 90 patients from a general ophthalmology clinic were studied, on whom an anterior pole OCT was performed (Cirrus Lumera 700 Carl Zeiss Medicte, Dublin, California, United States). All patients were included consecutively, with an analysis being performed on the cornea, anterior chamber, iris, lens, and anterior vitreous, but excluding those in which the test could not be performed.
RESULTS
The posterior lens capsule, the anterior hyaloid, and the BS between both structures were observed in three patients. This is the first time in the current literature that three cases have been described, together with their characteristics (one phakic -case 1- and two pseudophakic, one of them vitreous destructuring -case 2- and the other with opacification of the posterior capsule of the lens -case 3-), using this previous pole OCT technique.
CONCLUSIONS
Knowledge of the BS is essential to understand the vitreo-lenticular junction and any complications in some cataract surgeries, as well as to also understand the pathological origin of pigment dispersion syndrome.
Topics: Aged; Eye Diseases; Female; Humans; Lens, Crystalline; Male; Middle Aged; Tomography, Optical Coherence; Vitreous Body
PubMed: 31378388
DOI: 10.1016/j.oftal.2019.06.006 -
Vestnik Oftalmologii 2019The article analyzes existing information on clinical and experimental studies of vitreous changes in asteroid hyalosis, historical aspects of how this condition was...
The article analyzes existing information on clinical and experimental studies of vitreous changes in asteroid hyalosis, historical aspects of how this condition was studied over the past hundred years, its occurrence and pathogenesis. Results of various studies were used to evaluate current understanding of the forms and elemental composition of phospholipid mineral sedimentation on vitreous structures and methods of its examination. The problem of intravital assessment of the condition of vitreous body was analyzed, and a method was suggested for studying the macrostructure of hyaloid tracts and the state of the vitreous body by means of digital ultrasound in patients with asteroid hyalosis.
Topics: Eye Diseases; Humans; Ultrasonography; Vitreous Body
PubMed: 31691674
DOI: 10.17116/oftalma2019135052286 -
Retina (Philadelphia, Pa.) Jul 2021Vitreoretinal surgical techniques have evolved during the last decades because of the development and evolution of pars plana vitrectomy. The introduction of modern... (Review)
Review
BACKGROUND
Vitreoretinal surgical techniques have evolved during the last decades because of the development and evolution of pars plana vitrectomy. The introduction of modern vitrectomy is credited to Robert Machemer (1933-2009). The aim of this review is to characterize the early developments of vitreous removal.
METHODS
We used the PubMed web platform to search the terms: complications of cataract surgery, vitrectomy, vitreous body, vitreous humor, vitreous humour, vitreous tap, and vitreous transplantation. Other publications were also considered as a potential source of information when referenced in relevant articles.
RESULTS
The first description of vitreous removal for treatment of eye disorders dates the 17th century; it was conducted by a Dutch surgeon Anton Nuck (1650-1692) in a case of hydrophthalmia. In English literature, the first description of vitrectomy is attributed to the American surgeon John Collins Warren (1778-1856). This method was implemented in the spontaneous dislocation of the crystalline lens. As the fibrillar structure of the vitreous once destroyed could not be regenerated, the researchers aimed to restore the chemical composition of the vitreous. For several decades, vitreous transplantation was performed for the treatment of vitreous hemorrhages and retinal detachment.
CONCLUSION
Although the achievements of vitreoretinal surgery preceding Machemer's inventions are uncommonly reported, they have contributed to the concept and understanding of the treatment modalities.
Topics: Eye Diseases; History, 20th Century; History, 21st Century; Humans; Visual Acuity; Vitrectomy; Vitreous Body
PubMed: 33595257
DOI: 10.1097/IAE.0000000000003149 -
Translational Vision Science &... Sep 2022Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous... (Review)
Review
Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous substitute not only as a tamponade but also as a drug release system to tackle ocular diseases. This review provides an overview of the requirements for vitreous substitutes and discusses the current clinically applied as well as novel polymer-based vitreous substitutes as drug delivery systems, including their release mechanisms, efficiencies, challenges, and future perspectives.
Topics: Drug Liberation; Polymers; Retina; Vitrectomy; Vitreous Body
PubMed: 36125790
DOI: 10.1167/tvst.11.9.14 -
Drug Discovery Today Aug 2019Intravitreal injection is one of the major administration routes for the treatment of posterior ocular diseases. Intravitreal therapeutics usually suffer from... (Review)
Review
Intravitreal injection is one of the major administration routes for the treatment of posterior ocular diseases. Intravitreal therapeutics usually suffer from unsatisfactory efficacy owing to fast clearance from the vitreous humour and insufficient distribution into the retina. Engineered nanoparticles have been applied for specific tissue targeting over the past decades. In this review, we summarize the most recent research utilizing intravitreal nanoparticles to deliver therapeutics to the retina. Herein, the achievement made in preclinical research and challenges remaining in the field are highlighted. Parameters including size, charge, stability and choice of modified ligand on intraocular distribution and transport are also systematically discussed based on a proposed pharmacokinetic model. We provide insights for rational design principles for intravitreal nanoparticles for targeted retinal delivery.
Topics: Animals; Drug Delivery Systems; Humans; Intravitreal Injections; Nanoparticles; Pharmaceutical Preparations; Retina; Tissue Distribution; Vitreous Body
PubMed: 31102730
DOI: 10.1016/j.drudis.2019.05.005 -
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 -
Retina (Philadelphia, Pa.) Jul 2021
Topics: Fovea Centralis; Humans; Male; Microscopy, Acoustic; Retinal Diseases; Tomography, Optical Coherence; Vitreous Body
PubMed: 33965994
DOI: 10.1097/IAE.0000000000003201 -
Japanese Journal of Ophthalmology Jul 2016The presence of a posterior precortical vitreous pocket, referred to as a precortical pocket, implies that the vitreous cortex is formed into a collagen sheet separated... (Review)
Review
The presence of a posterior precortical vitreous pocket, referred to as a precortical pocket, implies that the vitreous cortex is formed into a collagen sheet separated from the gel in the macula. Along with strong vitreoretinal attachment at the fovea, the precortical pocket plays a role in perifoveal posterior vitreous detachments, which may lead to macular holes, premacular membranes, and ring-shaped proliferation in diabetic retinopathy. I and my colleagues published pioneer studies of the vitreous in postmortem eyes. Here, the role of the precortical pocket in various vitreoretinal interface diseases is discussed. Swept-source optical coherence tomography showed development of the precortical pocket, the connecting channel, and Cloquet's canal during early childhood. These findings raised the possibility that aqueous humor may drain into the precortical pocket. The physiologic role of the drainage route is also discussed. Crosstalk between the anterior chamber and macula is an attractive hypothesis and remains to be elucidated.
Topics: Humans; Macula Lutea; Tomography, Optical Coherence; Vitreous Body
PubMed: 27165709
DOI: 10.1007/s10384-016-0447-z