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Acta Medica Portuguesa Oct 2023A 17-year-old male was taken to the emergency department for decreased left visual acuity and floaters beginning that same day. There was a history of exposure to...
A 17-year-old male was taken to the emergency department for decreased left visual acuity and floaters beginning that same day. There was a history of exposure to pulmonary tuberculosis five years before (mother as index case) followed by a four-month period of isoniazid prophylaxis. The ophthalmic examination showed posterior and intermediate uveitis in the left eye. Laboratory tests were normal; IgG for herpes simplex 1 was positive and both the varicella-zoster virus and remaining serologic tests were negative. Chest radiography was normal. Two weeks later, an epiretinal membrane with risk of tractional retinal detachment was observed. The Mantoux tuberculin skin test showed an induration of 15 mm and the IGRA test was positive. Sputum and vitreous humor samples were collected. Quadruple therapy and prednisolone were started. Ten days later, a posterior vitreous detachment with underlying vitreous hematoma was observed. Posterior vitrectomy and peripheral endolaser were performed without complications. One month later, the microbiological results became available, with the identification of Mycobacterium tuberculosis. Corticosteroids were weaned progressively. Antituberculous drugs were maintained for six months. The patient made a full recovery.
Topics: Male; Humans; Child; Adolescent; Tuberculosis, Ocular; Vitreous Body; Vitrectomy; Eye Diseases; Mycobacterium tuberculosis
PubMed: 37080196
DOI: 10.20344/amp.19245 -
Mediators of Inflammation 2012The eye is a well-suited organ for local delivery of therapeutics to treat vitreous inflammation as well as other pathologic conditions that induce visual loss. Several... (Review)
Review
The eye is a well-suited organ for local delivery of therapeutics to treat vitreous inflammation as well as other pathologic conditions that induce visual loss. Several conditions are particularly challenging to treat and often require chronic courses of therapy. The use of implantable intravitreal devices for drug delivery is an emerging field in the treatment of vitreous inflammation as well as other ophthalmologic diseases. There are unique challenges in the design of these devices which include implants, polymers, and micro- and nanoparticles. This paper reviews current and investigational drug delivery systems for treating vitreous inflammation as well as other pathologic conditions that induce visual loss. The use of nonbiodegradable devices such as polyvinyl alcohol-ethylene vinyl acetate polymers and polysulfone capillary fibers, and biodegradable devices such as polylactic acid, polyglycolic acid, and polylactic-co-glycolic acid, polycaprolactones, and polyanhydrides are reviewed. Clinically used implantable devices for therapeutic agents including ganciclovir, fluocinolone acetonide, triamcinolone acetonide, and dexamethasone are described. Finally, recently developed investigational particulate drug delivery systems in the form of liposomes, microspheres, and nanoparticles are examined.
Topics: Animals; Drug Delivery Systems; Humans; Inflammation; Polymers; Vitreous Body
PubMed: 22988344
DOI: 10.1155/2012/126463 -
Progress in Retinal and Eye Research Jan 2018The development of the ocular vasculatures is perfectly synchronized to provide the nutritional and oxygen requirements of the forming human eye. The fetal vasculature... (Review)
Review
The development of the ocular vasculatures is perfectly synchronized to provide the nutritional and oxygen requirements of the forming human eye. The fetal vasculature of vitreous, which includes the hyaloid vasculature, vasa hyaloidea propria, and tunica vasculosa lentis, initially develops around 4-6 weeks gestation (WG) by hemo-vasculogenesis (development of blood and blood vessels from a common progenitor, the hemangioblast). This transient fetal vasculature expands around 12 WG by angiogenesis (budding from primordial vessels) and remains until a retinal vasculature begins to form. The fetal vasculature then regresses by apoptosis with the assistance of macrophages/hyalocytes. The human choroidal vasculature also forms by a similar process and will supply nutrients and oxygen to outer retina. This lobular vasculature develops in a dense collagenous tissue juxtaposed with a cell constitutively producing vascular endothelial growth factor (VEGF), the retinal pigment epithelium. This epithelial/endothelial relationship is critical in maintaining the function of this vasculature throughout life and maintaining it's fenestrated state. The lobular capillary system (choriocapillaris) develops first by hemo-vasculogenesis and then the intermediate choroidal blood vessels form by angiogenesis, budding from the choriocapillaris. The human retinal vasculature is the last to develop. It develops by vasculogenesis, assembly of CXCR4/CD39 angioblasts or vascular progenitors perhaps using Muller cell Notch1 or axonal neuropilinin-1 for guidance of semaphorin 3A-expressing angioblasts. The fovea never develops a retinal vasculature, which is probably due to the foveal avascular zone area of retina expressing high levels of antiangiogenic factors. From these studies, it is apparent that development of the mouse ocular vasculatures is not representative of the development of the human fetal, choroidal and retinal vasculatures.
Topics: Choroid; Humans; Neovascularization, Pathologic; Retina; Retinal Pigment Epithelium; Retinal Vessels; Vascular Endothelial Growth Factor A; Vitreous Body
PubMed: 29081352
DOI: 10.1016/j.preteyeres.2017.10.001 -
Investigative Ophthalmology & Visual... Dec 2014Collagen fiber remodeling in the vitreous body has been implicated in cases of vitreomacular traction, macular hole, and retinal detachment, and also may occur during...
PURPOSE
Collagen fiber remodeling in the vitreous body has been implicated in cases of vitreomacular traction, macular hole, and retinal detachment, and also may occur during pharmacologic vitreolysis. The purpose of this study was to evaluate quantitative polarized light imaging (QPLI) as a tool for studying fiber organization in the vitreous and near the vitreoretinal interface in control and enzymatically perturbed conditions.
METHODS
Fiber alignment was measured in anterior-posterior sections of bovine and porcine vitreous. Additional tests were performed on bovine lenses and nasal-temporal vitreous sections. Effects of proteoglycan degradation on collagen fiber alignment using trypsin and plasmin were assessed at the microstructural level using electron microscopy and at the global level using QPLI.
RESULTS
Control vitreous showed fiber organization patterns consistent with the literature across multiple-length scales, including the global anterior-posterior coursing of vitreous fibers, as well as local fibers parallel to the equatorial vitreoretinal interface and transverse to the posterior interface. Proteoglycan digestion with trypsin or plasmin significantly increased fiber alignment throughout the vitreous (P < 0.01). The largest changes (3×) occurred in the posterior vitreous where fibers are aligned transverse to the posterior vitreoretinal interface (P < 0.01).
CONCLUSIONS
Proteoglycan loss due to enzymatic vitreolysis differentially increases fiber alignment at locations where tractions are most common. We hypothesize that a similar mechanism leads to retinal complications during age-related vitreous degeneration. Structural changes to the entire vitreous body (as opposed to the vitreoretinal interface alone) should be evaluated during preclinical testing of pharmacological vitreolysis candidates.
Topics: Analysis of Variance; Animals; Cattle; Disease Models, Animal; Fibrillar Collagens; Fibrinolysin; Fibrinolytic Agents; Humans; Microscopy, Electron; Microscopy, Polarization; Proteoglycans; Retinal Diseases; Swine; Trypsin; Ultrasonography; Vitreous Body
PubMed: 25468895
DOI: 10.1167/iovs.14-15225 -
System-wide vitreous proteome dissection reveals impaired sheddase activity in diabetic retinopathy.Theranostics 2022Diabetic retinopathy (DR) is a major complication of diabetes mellitus causing significant vision loss. DR is a multifactorial disease involving changes in retinal...
Diabetic retinopathy (DR) is a major complication of diabetes mellitus causing significant vision loss. DR is a multifactorial disease involving changes in retinal microvasculature and neuronal layers, and aberrations in vascular endothelial growth factors (VEGF) and inflammatory pathways. Despite the success of anti-VEGF therapy, many DR patients do not respond well to the treatment, emphasizing the involvement of other molecular players in neuronal and vascular aberrations in DR. We employed advanced mass spectrometry-based proteome profiling to obtain a global snapshot of altered protein abundances in vitreous humor from patients with proliferative DR (PDR) in comparison to individuals with epiretinal membrane without active DR or other retinal vascular complications. Global proteome correlation map and protein-protein interaction networks were used to probe into the functional inclination of proteins and aberrated molecular networks in PDR vitreous. In addition, peptide-centric analysis of the proteome data was carried out to identify proteolytic processing, primarily ectodomain shedding events in PDR vitreous. Functional validation experiments were performed using preclinical models of ocular angiogenesis. The vitreous proteome landscape revealed distinct dysregulations in several metabolic, signaling, and immune networks in PDR. Systematic analysis of altered proteins uncovered specific impairment in ectodomain shedding of several transmembrane proteins playing critical roles in neurodegeneration and angiogenesis, pointing to defects in their regulating sheddases, particularly ADAM10, which emerged as the predominant sheddase. We confirmed that ADAM10 protease activity was reduced in animal models of ocular angiogenesis and established that activation of ADAM10 can suppress endothelial cell activation and angiogenesis. Furthermore, we identified the impaired ADAM10-AXL axis as a driver of retinal angiogenesis. We demonstrate restoration of aberrant ectodomain shedding as an effective strategy for treating PDR and propose ADAM10 as an attractive therapeutic target. In all, our study uncovered impaired ectodomain shedding as a prominent feature of PDR, opening new possibilities for advancement in the DR therapeutic space.
Topics: Animals; Diabetes Mellitus; Diabetic Retinopathy; Peptide Hydrolases; Proteome; Vascular Endothelial Growth Factors; Vitreous Body
PubMed: 36185601
DOI: 10.7150/thno.72947 -
Archiwum Medycyny Sadowej I Kryminologii 2017Biological materials used in toxicological analyses in forensic medicine traditionally include blood, urine and vitreous humour. Forensic use of the vitreous body is...
Biological materials used in toxicological analyses in forensic medicine traditionally include blood, urine and vitreous humour. Forensic use of the vitreous body is mostly due to the need to assess the endogenous concentration of ethyl alcohol in the process of human body decomposition. The vitreous body is an underestimated biological material, even though its biochemical properties and anatomical location make it suitable for specific forensic toxicology tests as a reliable material for the preparation of forensic expert opinions. Based on the available literature the paper gathers information on the biochemical structure of the vitreous body, ways to secure the material after collection and its use in postmortem diagnostics. Specific applications of the vitreous humour for biochemical and toxicological tests are discussed, with a focus on its advantages and limitations in forensic medical assessment which are attributable to its biochemical properties, anatomical location and limited scientific studies on the distribution of xenobiotics in the vitreous body.
Topics: Autopsy; Forensic Medicine; Forensic Toxicology; Humans; Postmortem Changes; Spectrometry, Mass, Electrospray Ionization; Vitreous Body
PubMed: 29460610
DOI: 10.5114/amsik.2017.73192 -
Ophthalmologica. Journal International... 2012This article gives an overview of the vitreal anatomy and its changes in ageing, which have a significant impact on the two main retinal complications after damage of... (Review)
Review
This article gives an overview of the vitreal anatomy and its changes in ageing, which have a significant impact on the two main retinal complications after damage of the vitreolenticular barrier, namely retinal detachment and cystoid macular edema. The possible reasons and pathomechanisms for this entity of retinal diseases in the context of anterior segment interaction are highlighted, and a summary of references is provided showing the epidemiology and consequences of such interventions.
Topics: Aging; Animals; Cataract Extraction; Humans; Lens, Crystalline; Macular Edema; Retinal Detachment; Vitrectomy; Vitreous Body
PubMed: 21952101
DOI: 10.1159/000330421 -
Scientific Reports Jun 2014Silicone oil has been the only long-term vitreous substitute used in the treatment of retinal detachment since 1962 by Cibis. Nevertheless, its effects on retinal...
Silicone oil has been the only long-term vitreous substitute used in the treatment of retinal detachment since 1962 by Cibis. Nevertheless, its effects on retinal vascular morphology and oxygen supply to the retina are ambiguous in current research. We previously invented a foldable capsular vitreous body (FCVB) to use as a new vitreous substitute in the treatment of severe retinal detachment, but its effects on the retinal vessel were unknown. Therefore, in this study, a standard three-port pars plana vitrectomy (PPV) was performed on the right eye of each rabbit and then silicone oil and FCVB were injected into the vitreous cavity as vitreous substitutes. After 180 days of retention, the retinal vascular morphology did not display any distinct abnormalities, and hypoxia-induced factor-1alpha (HIF-1α) and vascular endothelial growth factor (VEGF) did not vary markedly during the observation period in silicone oil tamponade- and FCVB-implanted eyes. This study may suggest that silicone oil and FCVB tamponade in rabbit eyes did not cause retinal vascular pathologic changes or retinal hypoxia for 180 days.
Topics: Animals; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Oxygen; Rabbits; Retina; Retinal Vessels; Silicone Oils; Vascular Endothelial Growth Factor A; Vitrectomy; Vitreous Body
PubMed: 24920425
DOI: 10.1038/srep05272 -
Scientific Reports Oct 2023We conducted a study to assess the pressure difference between the aqueous and vitreous humors in rabbit eyes using a direct intraocular pressure (IOP) measurement...
We conducted a study to assess the pressure difference between the aqueous and vitreous humors in rabbit eyes using a direct intraocular pressure (IOP) measurement method. A micro-optic-fiber pressure sensor was utilized for this purpose. Preliminary experiments with enucleated porcine eyes confirmed the sensor's accuracy in measuring both aqueous and vitreous humor pressure. The main study involved six healthy albino rabbits, where the sensor measured the pressure in the anterior chamber (aIOP) and posterior vitreous-cavity (pIOP). These measurements were compared to aIOP values obtained through rebound tonometry. Additionally, pre- and postoperative pressure comparisons were made after performing a vitrectomy. Results revealed a significant disparity between aqueous and vitreous humor pressures. Prior to vitrectomy, pIOP was 22.8 mmHg, over twice as high as aIOP (11.0 mmHg), but decreased to a similar level following the procedure. Comparison between the sensor measurements and rebound tonometry showed agreement in aIOP values. In conclusion, our study demonstrates that vitreous humor pressure is consistently higher than aqueous humor pressure, reaching the upper limit of normal IOP. Furthermore, vitrectomy effectively reduces pIOP, aligning it with aIOP. These findings contribute valuable insights into intraocular pressure dynamics and have implications for clinical interventions targeting ocular pressure regulation.
Topics: Animals; Swine; Rabbits; Vitreous Body; Intraocular Pressure; Vitrectomy; Tonometry, Ocular; Aqueous Humor
PubMed: 37880357
DOI: 10.1038/s41598-023-45616-z -
Indian Journal of Ophthalmology Sep 2020Pars plana vitrectomy (PPV) in uveitis is indicated for various diagnostic and therapeutic indications. With the advent of microincision vitreous surgery (MIVS), the use... (Review)
Review
Pars plana vitrectomy (PPV) in uveitis is indicated for various diagnostic and therapeutic indications. With the advent of microincision vitreous surgery (MIVS), the use of PPV in uveitis has increased with a wider spectrum of indications due to shorter surgical time, less patient discomfort, less conjunctival scarring, and a decreased rate of complications as compared to standard 20G vitrectomy. Because of faster post-operative recovery in terms of visual improvement and reduction of inflammation, and reduced duration of systemic corticosteroids, MIVS has gained popularity in uveitis as an adjunctive therapy to the standard of care medical therapy. The safety and efficacy of MIVS is related to the emerging vitrectomy techniques with better and newer cutters, illuminating probes, and accessory instruments. Because of the instrumentation and fluidics of MIVS, PPV is emerging as a safe and useful alternative for diagnostic challenges in uveitis, aiding in earlier diagnosis and better outcome of inflammatory disease, even in the presence of severe and active inflammation, which was once considered a relative contraindication for performing vitreous surgery. However, for surgical interventions for therapeutic indications and complications of uveitis, it is advisable to achieve an optimum control of inflammation for best results. The increasing reports of the use of MIVS in uveitis have led to its wider acceptance among clinicians practicing uveitis.
Topics: Humans; Retrospective Studies; Uveitis; Visual Acuity; Vitrectomy; Vitreous Body
PubMed: 32823401
DOI: 10.4103/ijo.IJO_1625_20