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Survey of Ophthalmology 2020Vitreous floaters are common, related to age, myopia, genetic predisposition, and infiltration of the vitreous body. A subset of patients report symptoms impacting their... (Review)
Review
Vitreous floaters are common, related to age, myopia, genetic predisposition, and infiltration of the vitreous body. A subset of patients report symptoms impacting their quality of vision. Treatment with laser vitreolysis, the use of an Nd:YAG laser to vaporize the collagenous vitreous opacities appears to be used more frequently; however, data regarding long-term safety and effectiveness are lacking. We present currently available data regarding efficacy and safety, as well as additional considerations. Laser vitreolysis of symptomatic floaters should not be routinely performed without additional studies documenting its safety and long-term efficacy. Ideally, the procedure would be effective in most patients and be approved by the Food and Drug Administration based on the results of a Food and Drug Administration registration trial before widespread adoption.
Topics: Eye Diseases; Humans; Laser Therapy; Lasers, Solid-State; Visual Acuity; Vitrectomy; Vitreous Body
PubMed: 32135173
DOI: 10.1016/j.survophthal.2020.02.007 -
Validation of the i-STAT®1 Analyzer for Postmortem Vitreous Humor Electrolytes and Glucose Analysis.Journal of Analytical Toxicology Mar 2018The analytical value of vitreous humor as a specimen in postmortem forensic toxicology has been known for some time. Numerous medical examiner laboratories outsource the...
The analytical value of vitreous humor as a specimen in postmortem forensic toxicology has been known for some time. Numerous medical examiner laboratories outsource the analysis of this important specimen for electrolyte and glucose measurements. This can be both time-consuming and costly. The utility of the i-STAT®1 medical device to measure electrolytes and glucose in whole blood samples has been demonstrated for over two decades in a clinical setting through single-use disposable cartridges that introduce samples to the i-STAT®1. Different cartridge types allow for the analysis of various analytes including sodium, potassium, chloride, creatinine, urea nitrogen and glucose. With only 100 μL of sample, results are obtained in under 4 min. In this study, we utilized the i-STAT®1 using an alternative specimen matrix, postmortem vitreous humor and quantitatively determined the validity and reliability of the instrument for this purpose. Acceptable criterion was used for each test as suggested by the Scientific Working Group for Forensic Toxicology. All analytes of interest, except creatinine, demonstrated a percent error < ±10% for both accuracy and precision studies. Drug interference and stability studies were performed with many of the analytes demonstrating a percent error < ±20%. Throughout drug interference and stability studies, all analytes of interest were detectable except for potassium, which gave inconclusive results. Significant interference with commonly found drugs were shown for creatinine and chloride but must be evaluated carefully. Volume additions to ethanol spiked samples caused significant interference for all analytes and is considered a limitation for this method of analysis that requires additional studies. As vitreous humor continues to be used in forensic medicine to aid in diagnostic interpretation, the i-STAT®1 has the potential to give accurate results in a timely and cost-effective manner.
Topics: Autopsy; Electrolytes; Equipment Design; Forensic Toxicology; Glucose; Humans; Reproducibility of Results; Specimen Handling; Vitreous Body
PubMed: 29186446
DOI: 10.1093/jat/bkx084 -
Translational Vision Science &... Apr 2022A growing body of evidence suggests complement dysregulation is present in the vitreous of patients with diabetic eye disease. Further translational study could be...
PURPOSE
A growing body of evidence suggests complement dysregulation is present in the vitreous of patients with diabetic eye disease. Further translational study could be simplified if aqueous-as opposed to vitreous-were used to sample the intraocular complement environment. Here, we analyze aqueous samples and assess whether a correlation exists between aqueous and vitreous complement levels.
METHODS
We collected aqueous, vitreous, and plasma samples from patients with and without proliferative diabetic retinopathy (PDR) undergoing vitrectomy. We assessed correlation between complement levels in aqueous and vitreous samples after using a normalizing ratio to correct for vascular leakage. Spearman correlation coefficients were used to assess the correlation between complement levels in the aqueous and vitreous.
RESULTS
Aqueous samples were obtained from 17 cases with PDR and 28 controls. In all patients, aqueous Ba, C3a, and albumin levels were strongly correlated with vitreous levels (Spearman correlation coefficient of 0.8 for Ba and C3a and 0.7 for albumin; all P values < 0.0001). In PDR eyes only, aqueous and vitreous C3a levels were significantly correlated (Spearman correlation coefficient 0.7; P = 0.002), whereas in control eyes, both Ba and C3a (Spearman correlation coefficients of 0.7; P < 0.0001) were significantly correlated.
CONCLUSIONS
A strong correlation exists between aqueous and vitreous complement levels in diabetic eye disease.
TRANSLATIONAL RELEVANCE
The results establish that accurate sampling of the intraocular complement can be done by analyzing aqueous specimens, allowing for the rapid and safe measurement of experimental complement targets and treatment response.
Topics: Albumins; Aqueous Humor; Complement Activation; Complement System Proteins; Diabetes Mellitus; Diabetic Retinopathy; Humans; Vitreous Body
PubMed: 35420644
DOI: 10.1167/tvst.11.4.13 -
Survey of Ophthalmology 2022Postoperative endophthalmitis is a dreaded complication of intraocular surgery. Acute presentations need prompt management and good knowledge of differential diagnoses.... (Review)
Review
Postoperative endophthalmitis is a dreaded complication of intraocular surgery. Acute presentations need prompt management and good knowledge of differential diagnoses. In the last 10 years, progress in direct microbial detection and identification from intraocular samples included the use of blood culture systems and, more recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, improving the rate of bacterial identification. Whatever the method used, diagnostic sensitivity is better for vitreous samples than for aqueous humor samples. Besides, molecular biology techniques have further improved the identification rate of infectious agents in intraocular samples. They also provide faster results compared to culture-based techniques. Quantitative real-time PCR (qPCR) can also determine the bacterial load in intraocular samples. Several studies have shown that intraocular bacterial loads in endophthalmitis patients are usually high, which helps differentiating infection from contamination. The prognostic value of qPCR remains to be validated. Whole genome DNA sequencing technologies facilitate direct and sequencing of single DNA molecules. They have the potential to increase the rate of microbiological identification. Some antibiotic resistance markers (e.g., methicillin resistance in staphylococci and vancomycin resistance in enterococci) may be detected earlier using molecular techniques (usually real-time PCR tests). Early determination of the involved microorganism and their antibiotic resistances can help establishing an earlier therapeutic strategy.
Topics: Anti-Bacterial Agents; Aqueous Humor; DNA, Bacterial; Endophthalmitis; Eye Infections, Bacterial; Humans; Polymerase Chain Reaction; Postoperative Complications; Vitreous Body
PubMed: 35843367
DOI: 10.1016/j.survophthal.2022.07.001 -
Journal of Proteome Research May 2021The postmortem diagnosis of hypothermia fatalities is often complex due to the absence of pathognomonic lesions and biomarkers. In this study, potential novel biomarkers...
The postmortem diagnosis of hypothermia fatalities is often complex due to the absence of pathognomonic lesions and biomarkers. In this study, potential novel biomarkers of hypothermia fatalities were searched in the vitreous humor of known cases of hypothermia fatalities ( = 20) compared to control cases ( = 16), using a targeted metabolomics approach allowing quantitative detection of 188 metabolites. A robust discriminant model with good predictivity was obtained with the supervised OPLS-DA multivariate analysis, showing a distinct separation between the hypothermia and control groups. This signature was characterized by the decreased concentrations of five metabolites (methionine sulfoxide, tryptophan, phenylalanine, alanine, and ornithine) and the increased concentration of 28 metabolites (21 phosphatidylcholines, 3 sphingomyelins, spermine, citrulline, acetylcarnitine, and hydroxybutyrylcarnitine) in hypothermia fatalities compared to controls. The signature shows similarities with already identified features in serum such as the altered concentrations of tryptophan, acylcarnitines, and unsaturated phosphatidylcholines, revealing a highly significant increased activity of methionine sulfoxide reductase, attested by a low methionine sulfoxide-to-methionine ratio. Our results show a preliminary metabolomics signature of hypothermia fatalities in the vitreous humor, highlighting an increased methionine sulfoxide reductase activity.
Topics: Biomarkers; Body Fluids; Humans; Hypothermia; Metabolomics; Vitreous Body
PubMed: 33818108
DOI: 10.1021/acs.jproteome.0c00901 -
Pharmacological Research Sep 2021Diabetic retinopathy (DR) is one of the common complications in diabetic patients. Nowadays, VEGF pathway is subject to extensive research. However, about 27% of the...
Diabetic retinopathy (DR) is one of the common complications in diabetic patients. Nowadays, VEGF pathway is subject to extensive research. However, about 27% of the patients have a poor visual outcome, with 50% still having edema after two years' treatment of diabetic macular edema (DME) with ranibizumab. Docosahexaenoic acid (DHA), the primary ω-3 long-chain polyunsaturated fatty acid (LC-PUFA), reduces abnormal neovascularization and alleviates neovascular eye diseases. A study reported that fish oil reduced the incidence of retinopathy of prematurity (ROP) by about 27.5% in preterm infants. Although ω-3 LC-PUFAs protects against pathological retinal neovascularization, the treatment effectiveness is low. It is interesting to investigate why DHA therapy fails in some patients. In human vitreous humor samples, we found that the ratio of DHA and DHA-derived metabolites to total fatty acids was higher in vitreous humor from DR patients than that from macular hole patients; however, the ratio of DHA metabolites to DHA and DHA-derived metabolites was lower in the diabetic vitreous humor. The expression of Mfsd2a, the LPC-DHA transporter, was reduced in the oxygen-induced retinopathy (OIR) model and streptozotocin (STZ) model. In vitro, Mfsd2a overexpression inhibited endothelial cell proliferation, migration and vesicular transcytosis. Moreover, Mfsd2a overexpression in combination with the DHA diet obviously reduced abnormal retinal neovascularization and vascular leakage, which is more effective than Mfsd2a overexpression alone. These results suggest that DHA therapy failure in some DR patients is linked to low expression of Mfsd2a, and the combination of Mfsd2a overexpression and DHA therapy may be an effective treatment.
Topics: Animals; Cell Line; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Docosahexaenoic Acids; Endothelial Cells; Female; Humans; Macular Edema; Male; Mice, Inbred C57BL; Retina; Symporters; Vitreous Body; Wound Healing; Mice
PubMed: 34229049
DOI: 10.1016/j.phrs.2021.105755 -
Journal of Forensic Sciences May 2019Vitreous humor (VH) and synovial fluid (SF) become optional postmortem samples for biochemistry investigation. However, few studies have explored SF as a potential... (Comparative Study)
Comparative Study
Vitreous humor (VH) and synovial fluid (SF) become optional postmortem samples for biochemistry investigation. However, few studies have explored SF as a potential source, and there is still controversy whether the biochemical concentrations in bilateral VH are the same. We explored the concentrations of biochemical substances in both VH and SF, and compared between both sides and between the fluids. We also correlated the biochemical concentrations in both fluids. All samples were centrifuged after collection and the supernatant fluids were used for the analysis. The results indicated no significant difference in the constituent concentrations between the fluids from both sides (p > 0.05). Sodium, potassium, chloride, and magnesium concentrations were significantly higher in the VH, but in vice versa for glucose, uric acid, and creatinine concentrations (p < 0.001). Sodium, potassium, glucose, lactate, urea, uric acid, and creatinine concentrations between both fluids showed significant correlation (p < 0.05), but not chloride and magnesium concentrations.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Chlorides; Cohort Studies; Correlation of Data; Creatinine; Female; Forensic Medicine; Glucose; Humans; Lactates; Magnesium; Male; Middle Aged; Potassium; Regression Analysis; Sodium; Synovial Fluid; Uric Acid; Vitreous Body; Young Adult
PubMed: 30931532
DOI: 10.1111/1556-4029.13966 -
PloS One 2020The aim of this study was to investigate whether and how the biological media which are in contact with silicone oil play a role in the silicone emulsification process....
The aim of this study was to investigate whether and how the biological media which are in contact with silicone oil play a role in the silicone emulsification process. Commercially available Oxane 1300 silicone oil and potential hydrophilic phases of the emulsions in the eye (porcine aqueous humor, porcine vitreous and balanced salt solution) were investigated separately and in a mixture or emulsions by means of surface tension, rheological, zeta potential measurements and microscopic investigation. The surface tension of biological media (vitreous and aqueous humor) was significantly lower than that of non-biological media, especially in the case of aqueous humor, which indicates a remarkable emulsification tendency with these phases. The biological media are able to form both oil-in-water and water-in-oil emulsions, which can be observed in the clinical practice as well. It was established that the vitreous has a more expressed emulsification ability compared with the aqueous humor because smaller and more stable droplets can form with silicon oil when the vitreous is still there. It can be concluded that the vitreous has a higher impact on emulsification than the aqueous medium, which can predict that the vitreous remaining after vitrectomy has a key role in emulsion formation in the eye with silicone oil endotamponade.
Topics: Animals; Aqueous Humor; Emulsions; Isotonic Solutions; Rheology; Silicone Oils; Surface Tension; Swine; Vitrectomy; Vitreous Body
PubMed: 32559226
DOI: 10.1371/journal.pone.0235067 -
Forensic Science International Sep 2023Traumatic brain injury (TBI) is one of the major causes of morbidity and mortality worldwide. The patients' and injuries' heterogeneity associated with TBI, alongside...
BACKGROUND
Traumatic brain injury (TBI) is one of the major causes of morbidity and mortality worldwide. The patients' and injuries' heterogeneity associated with TBI, alongside with its variable clinical manifestations, make it challenging to make diagnosis and predict prognosis. Therefore, the identification of reliable prognostic markers would be relevant both to support clinical decision-making and forensic evaluation of polytraumatic deaths and cases of medical malpractice. This pilot study aimed to evaluate some of the main biomarkers specific for brain damage in sTBI and mmTBI deaths in samples of vitreous humor (VH) in order to verify whether predictors of prognosis in TBI can be found in this matrix.
METHODS
VH were obtained from both eyes (right and left) of 30 cadavers (20 sTBI and 10 mmTBI) and analysed. These factors were evaluated: NSE (neuron-specific enolase), S100 calcium-binding protein (S100), glial fibrillary acidic protein (GFAP), Brain-derived neurotrophic factor (BDNF), Copeptin, Interleukin 6 (IL-6), Ferritin, Lactate dehydrogenase (LDH), C-Reactive Protein (CRP), Procalcitonin (PCT), Glucose and Neutrophil gelatinase-associated lipocalin (N-Gal).
RESULTS
Four of the analysed proteins (LDH, ferritin, S100 and NSE) proved to be particularly promising. In particular, logistic regression analysis found a good discriminatory power.
CONCLUSIONS
Given the peculiarity of the matrix and the poor standardization of the sampling, such promising results need to be furtherly investigated in serum before being implemented in the forensic practice.
Topics: Humans; Pilot Projects; Vitreous Body; S100 Calcium Binding Protein beta Subunit; Brain Injuries, Traumatic; Biomarkers; Glial Fibrillary Acidic Protein; Ferritins
PubMed: 37467521
DOI: 10.1016/j.forsciint.2023.111782 -
Cells May 2022Retinoblastoma (Rb) is a pediatric intraocular malignancy that is proposed to originate from maturing cone cell precursors in the developing retina. The molecular...
Integrated Analysis of Cancer Tissue and Vitreous Humor from Retinoblastoma Eyes Reveals Unique Tumor-Specific Metabolic and Cellular Pathways in Advanced and Non-Advanced Tumors.
Retinoblastoma (Rb) is a pediatric intraocular malignancy that is proposed to originate from maturing cone cell precursors in the developing retina. The molecular mechanisms underlying the biological and clinical behaviors are important to understand in order to improve the management of advanced-stage tumors. While the genetic causes of Rb are known, an integrated understanding of the gene expression and metabolic processes in tumors of human eyes is deficient. By integrating transcriptomic profiling from tumor tissues and metabolomics from tumorous eye vitreous humor samples (with healthy, age-matched pediatric retinae and vitreous samples as controls), we uncover unique functional associations between genes and metabolites. We found distinct gene expression patterns between clinically advanced and non-advanced Rb. Global metabolomic analysis of the vitreous humor of the same Rb eyes revealed distinctly altered metabolites, indicating how tumor metabolism has diverged from healthy pediatric retina. Several key enzymes that are related to cellular energy production, such as hexokinase 1, were found to be reduced in a manner corresponding to altered metabolites; notably, a reduction in pyruvate levels. Similarly, E2F2 was the most significantly elevated E2F family member in our cohort that is part of the cell cycle regulatory circuit. Ectopic expression of the wild-type gene in the Rb-null Y79 and WERI-Rb1 cells rescued hexokinase 1 expression, while E2F2 levels were repressed. In an additional set of Rb tumor samples and pediatric healthy controls, we further validated differences in the expression of HK1 and E2F2. Through an integrated omics analysis of the transcriptomics and metabolomics of Rb, we uncovered a significantly altered tumor-specific metabolic circuit that reduces its dependence on glycolytic pathways and is governed by Rb1 and HK1.
Topics: Child; Hexokinase; Humans; Retinal Neoplasms; Retinoblastoma; Retinoblastoma Protein; Vitreous Body
PubMed: 35626705
DOI: 10.3390/cells11101668