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Nippon Ganka Gakkai Zasshi Mar 2015The macula is a site where various vitreoretinal disorders occur. In 1983 we started to observe the retinal surface of postmortem eyes with a scanning electron... (Review)
Review
The macula is a site where various vitreoretinal disorders occur. In 1983 we started to observe the retinal surface of postmortem eyes with a scanning electron microscope (SEM). We investigated the anatomy of the vitreous in postmortem eyes by slit lamp biomicroscopy. The novel anatomy of the premacular vitreous led us to conduct a clinical study of vitreomacular interface diseases. In 1997, time domain optical coherence tomography(OCT) became available which facilitated visualization of the vitreoretinal interface. Swept source OCT which was introduced in 2012 can depict liquefied lacunae in the vitreous. It enabled us to elucidate the mechanism of vitreoretinal diseases. I. SEM revealed the remnants of vitreous cortex at fovea with high incidence (44%), which suggests strong vitreoretinal attachment at the fovea and vitreous cortex origin of the epiretinal membrane. II. We studied the anatomy of the vitreous in postmortem eyes. The vitreous of bisected eye balls was stained by fluorescein and immersed in water and observed by slit-lamp biomicroscopy. We discovered a "posterior precortical vitreous pocket (PPVP)" in adult eyes without posterior vitreous detachment (PVD). III. We performed clinical study in various vitreoretinal diseases based on the novel vitreous anatomy and explained their mechanism. 1. In diabetic retinopathy, ring shaped fibrovascular tissue surrounding the macula is formed along the outer margin of the PPVP. Although PVD progresses outside the PPVP, its posterior wall remains attached to the retina, which causes macular traction or cystoid macular edema. 2. In eyes with idiopathic epimacular membrane (IEM), detached vitreous cortex had an oval defect corresponding to the IEM. Posterior wall of the PPVP that is premacular vitreous cortex appeared to be the framework of IEM. 3. During vitrectomy for macular hole, premacular round defect appears when PVD is created. The residual cortex on the macula is fibrous membrane with elasticity. The tangential contraction of premacular cortex may generate anterior traction to the fovea, which leads to macular hole. IV. Using time domain OCT, we demonstrated the evolution of macular hole, myopic foveoschisis and lamellar macular hole. After 2007, we investigated age related changes of vitreoretinal interface by spectral domain OCT V. We demonstrated whole structure of the PPVP using swept source OCT. PPVP is a boat shaped premacular liquefied space which has a connecting channel to Cloquet's canal. PPVP develops during childhood. Visualization of vitreous structure proved that our previous assumptions are reasonable. Although the physiological function of the PPVP is unclear, we speculate that the aqueous flows into the PPVP though Cloquet's canal and the connecting channel.
Topics: Diabetic Retinopathy; Humans; Macula Lutea; Microscopy, Electron; Visual Perception; Vitrectomy; Vitreous Body
PubMed: 25854107
DOI: No ID Found -
Translational Vision Science &... Feb 2023The purpose of this study was to assess the performance of ultrasonic (US) vitrectomy devices by quantifying and comparing its impact on extracted vitreous properties to...
PURPOSE
The purpose of this study was to assess the performance of ultrasonic (US) vitrectomy devices by quantifying and comparing its impact on extracted vitreous properties to conventional pneumatic blade (PB) cutters using micro-extensional rheology. US vitrectomy is a new technology that offers an alternative to PB cutters used in vitreo-retinal surgeries.
METHODS
Thirty-six porcine vitreous samples were extracted using US and PB cutters. Each sample was kept at 4°C and tested within 24 hours postmortem and 4 hours post-vitrectomy. A recently developed micro-extensional rheology technique is used to infer the relative protein fragment size of extracted vitreous by quantifying the extensional relaxation time.
RESULTS
US-extracted vitreous exhibited extensional relaxation times orders of magnitude lower than PB-extracted vitreous (0.37 ms and 27.25 ms, respectively). Relaxation time is directly correlated to the fragment size of the collagen fibers in the vitreous. The formation of beads-on-a-string droplets within the PB samples indicates the presence of larger collagen fragments. These droplets were not seen on US samples.
CONCLUSIONS
This new micro-extensional rheology technique can identify significant differences in physical properties of extracted vitreous. Long relaxation times and beads-on-a-string droplets within the PB vitreous samples indicate larger protein fragments compared to the US samples.
TRANSLATIONAL RELEVANCE
Higher fragmentation of vitreous and lower extensional relaxation times may improve retina safety due to a reduction in vitreo-retinal traction resulting from the continuous shear action and aspiration applied by ultrasonic vitrectomy technology.
Topics: Swine; Animals; Vitrectomy; Vitreous Body; Ultrasonics; Collagen; Rheology
PubMed: 36790819
DOI: 10.1167/tvst.12.2.24 -
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 -
Graefe's Archive For Clinical and... Jul 2020To investigate osteopontin (OPN) expression in vitreous and in related idiopathic epiretinal membranes (ERMs), with respect to VEGF-A, IL8, MIP1α, IL6, and IL33, and...
PURPOSE
To investigate osteopontin (OPN) expression in vitreous and in related idiopathic epiretinal membranes (ERMs), with respect to VEGF-A, IL8, MIP1α, IL6, and IL33, and correlate OPN expression with disease staging.
METHODS
Fifteen (15) vitreous and allied ERMs were collected at the time of therapeutic vitreoretinal surgery. Additional 5 vitreous and 10 ERMs (historical collection) were used. Biochemical and molecular analysis of OPN was performed in clear vitreous, vitreal pelleted cells, and ERMs. Double-immunofluorescence analysis (OPN - GFAP and OPN - αSMA) was performed on paraffin and whole-mounted ERMs. Vitreal OPN levels were correlated to those of VEGF-A, IL8, MIP1α, IL6, and IL33.
RESULTS
High OPN levels were observed in vitreal samples, and OPN transcripts were amplified in vitreal cells and related ERMs. OPN immunoreactivity was found in ERMs, mainly in GFAP-bearing (Muller cells) and to a less extend in αSMA-expressing (myofibroblasts) cells. OPN levels were highest at early stages of ERM formation and positively correlated to VEGF-A and MIP1α.
CONCLUSIONS
High OPN levels in vitreous, OPN transcripts in vitreal cells/ERMs, OPN immunoreactivity in activated Müller cells and contractile myofibroblasts, as well as the correlation with VEGF-A and MIP1α fulfill the potential involvement of OPN in both inflammation and tissue remodeling that takes part in vitreoretinal interface disorders. The highest OPN levels at early stages of ERM formation would prospect OPN as a potential biomarker for disease severity.
Topics: Aged; Biomarkers; Enzyme-Linked Immunosorbent Assay; Epiretinal Membrane; Female; Humans; Male; Osteopontin; Vitrectomy; Vitreous Body
PubMed: 32277255
DOI: 10.1007/s00417-020-04685-w -
European Journal of Ophthalmology Jul 2022To investigate sensitivity of diagnostic vitrectomy and vitreous biopsy for patients with vitritis of unknown aetiology.
PURPOSE
To investigate sensitivity of diagnostic vitrectomy and vitreous biopsy for patients with vitritis of unknown aetiology.
METHODS
Retrospective analysis of all vitrectomies and vitreous biopsies, performed at St Thomas' Hospital, London, UK, for vitritis between February 2001 and February 2019. Patients were identified using the VITREOR database and records were reviewed. Patients were categorised as infectious, non-infectious or masquerade based on final diagnosis. Sensitivity of both diagnostic pars plana vitrectomy (PPV) and vitreous cutter biopsy in each category was investigated. Furthermore, data on gender, age, and method of anaesthesia were also collected.
RESULTS
In our cohort, 64 patients underwent PPV with a diagnostic sensitivity of 67% (43/64) overall and 60% (18/30), 56% (9/16) and 89% (16/18) for those with infectious, masquerade and non-infectious aetiologies, respectively. In comparison, 96 patients underwent a vitreous cutter biopsy with diagnostic sensitivity of 74% (71/96) overall and 71% (55/77), 67% (4/6) and 92% (12/13) for those with infectious, masquerade and non-infectious aetiologies, respectively. No statistically significant difference in sensitivity was identified between the vitrectomy and vitreous biopsy groups for either aetiology. Patients undergoing vitrectomy were noted to be older ( = 0.02) and more likely to undergo a general anaesthetic ( < 0.01).
CONCLUSIONS
Herein we demonstrate similar diagnostic sensitivity of PPV and vitreous cutter biopsy in patients with vitritis of unknown aetiology.
Topics: Biopsy; Endophthalmitis; Humans; Orbital Diseases; Retrospective Studies; Vitrectomy; Vitreous Body
PubMed: 34459269
DOI: 10.1177/11206721211041025 -
Biomedical Materials (Bristol, England) Jun 2021Vitreoretinal surgery is an essential approach to treat proliferative diabetic vitreopathy, retinal detachment, retinal tear, ocular trauma, and macular holes. The... (Review)
Review
Vitreoretinal surgery is an essential approach to treat proliferative diabetic vitreopathy, retinal detachment, retinal tear, ocular trauma, and macular holes. The removal of the natural vitreous and the replacement with substitutes are critical steps for retina reattachment. Vitreous substitutes including silicone oil (SiO), air, sulfur hexafluoride (SF), and perfluoropropane (CF), have been widely applied in clinical practice. However, these substitutes are reported to cause complications such as emulsification, high intraocular pressure, and lens opacification. Polymeric hydrogels are a kind of material with favorable physical, mechanical properties, and adaptable biocompatibility, thus being highly expected to be ideal vitreous substitutes. Despite years of research, very few polymeric hydrogels can be applied practically in the vitreous cavity. In this review, we focus on the development of polymeric natural-based hydrogels and synthetic hydrogels. Particularly, we pay attention to recent advances in the novel stimuli-response and self-assembly supramolecular hydrogels. Characterized by easy injectability and long residence time, this kind of hydrogel becomes the potentially promising candidates for ideal vitreous substitutes. Finally, we evaluate the current challenges and provide the future directions of vitreous substitutes.
Topics: Animals; Biocompatible Materials; Humans; Hydrogels; Mice; Polymers; Vitreous Body
PubMed: 34038870
DOI: 10.1088/1748-605X/ac058e -
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 -
Diabetes Care Sep 2022To correlate inflammatory cytokines and vascular endothelial growth factor (VEGF) in vitreous and plasma with vitreous retinol binding protein 3 (RBP3), diabetic...
OBJECTIVE
To correlate inflammatory cytokines and vascular endothelial growth factor (VEGF) in vitreous and plasma with vitreous retinol binding protein 3 (RBP3), diabetic retinopathy (DR) severity, and DR worsening in a population with type 1 and type 2 diabetes.
RESEARCH DESIGN AND METHODS
RBP3, VEGF, and inflammatory cytokines were measured in plasma and vitreous samples (n = 205) from subjects of the Joslin Medalist Study and Beetham Eye Institute.
RESULTS
Higher vitreous RBP3 concentrations were associated with less severe DR (P < 0.0001) and a reduced risk of developing proliferative DR (PDR) (P < 0.0001). Higher RBP3 correlated with increased photoreceptor segment thickness and lower vitreous interleukin-12 (IL-12), tumor necrosis factor-α (TNF-α), and TNF-β (P < 0.05). PDR was associated with lower vitreous interferon-γ and IL-10 and higher VEGF, IL-6, and IL-15 (P < 0.05), but was not associated with their plasma concentrations.
CONCLUSIONS
Higher vitreous RBP3 concentrations are associated with less severe DR and slower rates of progression to PDR, supporting its potential as a biomarker and therapeutic agent for preventing DR worsening, possibly by lowering retinal VEGF and inflammatory cytokines.
Topics: Cytokines; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Enzyme-Linked Immunosorbent Assay; Eye Proteins; Humans; Retinol-Binding Proteins; Vascular Endothelial Growth Factor A; Vitreous Body
PubMed: 35852358
DOI: 10.2337/dc22-0165 -
Vestnik Oftalmologii 2023There are two main age-related changes that can occur in the vitreous body of healthy individuals throughout life: liquefaction (synchesis) and aggregation of collagen...
There are two main age-related changes that can occur in the vitreous body of healthy individuals throughout life: liquefaction (synchesis) and aggregation of collagen fibrils into dense bundles (syneresis). Progressive age-related degradation leads to posterior vitreous detachment (PVD). At present many classifications of PVD exist, in which authors relied either on the morphological features, or on the differences in pathogenesis before and after widespread use of OCT. The course of PVD can be either normal or anomalous. Physiological PVD induced by age-related vitreous changes progresses in specific stages. The review emphasizes that PVD can occur initially not only in the central zone of the retina, but also on the periphery with further spread to the posterior pole. Anomalous PVD can lead to various negative effects on the retina, as well as on the vitreous as a result of traction in the area of vitreoretinal interface.
Topics: Humans; Vitreous Body; Vitreous Detachment; Retina; Tomography, Optical Coherence
PubMed: 37379116
DOI: 10.17116/oftalma2023139031106 -
Ophthalmology Mar 2016
Topics: Angiogenesis Inhibitors; Female; Humans; Intravitreal Injections; Macula Lutea; Male; Vitreous Body; Vitreous Detachment; Wet Macular Degeneration
PubMed: 26902569
DOI: 10.1016/j.ophtha.2015.10.005