116 research outputs found
The UK paediatric ocular trauma study 2 (POTS2):Demographics and mechanisms of injuries
Freda Sii,1,2 Robert J Barry,1 Joseph Abbott,3 Richard J Blanch,1,4 Caroline J MacEwen,5 Peter Shah1,2,6,7 1Department of Ophthalmology, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation Trust, Birmingham, 2Birmingham Institute for Glaucoma Research, Institute of Translational Medicine, University Hospitals Birmingham NHS Foundation Trust, Birmingham, 3Department of Ophthalmology, Birmingham Children’s Hospital NHS Foundation Trust, Birmingham, 4Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, 5Department of Ophthalmology, Ninewells Hospital and Medical School, Dundee, 6National Institute of Health Research Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, 7Centre for Health and Social Care Improvement, School of Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK Purpose: Pediatric ocular trauma is an important cause of visual morbidity worldwide, accounting for up to one-third of all ocular trauma admissions. It has long-term implications for those affected and significant economic consequences for healthcare providers. It has been estimated that 90% of all ocular trauma is preventable. Targeted strategies are required to reduce the incidence and the severity of pediatric ocular trauma; this requires an understanding of the epidemiology and characteristics of these injuries and the children involved. Methods: Prospective, observational study of pediatric ocular trauma cases presenting to UK-based ophthalmologists over a 1-year period; reporting cards were distributed by the British Ophthalmological Surveillance Unit, and clinicians were asked to report incidents of acute orbital and ocular trauma in children aged ≤16 years requiring inpatient or day-case admission. A validated, standardized questionnaire was sent to reporting ophthalmologists to collect data on the demographics and circumstances of injury. Results: Median age at presentation was 7.7 years, with boys more than twice as likely to be affected than girls (M:F =2.1:1.0). Almost 50% of injuries occurred at home, with 25% occurring in school or nursery. A total of 67% of injuries occurred during play, and 31% involved a sharp implement. Conclusion: Pediatric ocular trauma remains an important public health problem. At least three-quarters of all injuries are preventable through measures, including education of children and responsible adults, restricting access to sharp implements, improving adult supervision, and appropriate use of eye protection. Keywords: etiology, childhood eye injury, epidemiology, penetrating eye injury, perforating eye injury, preventio
The UK Paediatric Ocular Trauma Study 1 (POTS1):development of a global standardized protocol for prospective data collection in pediatric ocular trauma
Freda Sii,1,2 Robert J Barry,1 Richard J Blanch,1 Joseph Abbott,3 Caroline J MacEwen,4 Peter Shah1,2,5,6 1Department of Ophthalmology, Queen Elizabeth Hospital Birmingham, 2Birmingham Institute for Glaucoma Research, Institute of Translational Medicine, University Hospitals Birmingham NHS Foundation Trust, 3Department of Ophthalmology, Birmingham Children’s Hospital NHS Foundation Trust, Birmingham, 4Department of Ophthalmology, Ninewells Hospital and Medical School, Dundee, 5National Institute of Health Research Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, 6Centre for Health and Social Care Improvement, School of Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK Background: Ocular trauma is an important cause of visual morbidity in children worldwide. Pediatric ocular trauma accounts for up to one third of all ocular trauma admissions, with significant economic implications for health care providers. It is estimated that 90% of all ocular trauma is preventable. Development of strategies to reduce the incidence and severity of pediatric ocular trauma requires an understanding of the epidemiology of these injuries and their characteristics. This will enable appropriate targeting of resources toward prevention and allow effective service planning. At present, there is no standardized methodology for the collection of global cross-sectional data in pediatric ocular trauma, and the ability to undertake detailed epidemiological and health-economic analyses is limited. Furthermore, it is difficult to draw international comparisons in incidence, etiology, and outcomes of pediatric ocular trauma due to the range of published reporting criteria. This study describes two novel questionnaires for standardized data collection in pediatric ocular trauma, which can be adopted across a range of health care settings internationally.Methods: Two standardized data collection questionnaires have been developed from previously reported templates. The first enables collection of demographic and incident data on serious pediatric ocular trauma requiring hospitalization, and the second enables follow-up outcome data collection. Both the questionnaires are designed to collect primarily categorical data in order to increase ease of completion and facilitate quantitative analysis. These questionnaires enable acquisition of standardized data on the incidence, etiology, and outcomes of pediatric ocular trauma.Discussion: These questionnaires enable collection of standardized data and are designed for global use across all health care settings. Through prospective data collection, epidemiological trends can be determined, allowing health care providers to develop collaborative global preventive strategies. Furthermore, the same questionnaires may be used in future studies to draw comparisons with baseline data, allowing assessment of the efficacy of targeted preventative interventions. Keywords: childhood eye injury, epidemiology, health economic analyses, international standardization, penetrating eye injury, perforating eye injury, preventio
The UK Paediatric Ocular Trauma Study 3 (POTS3):clinical features and initial management of injuries
Window into the mind:Advanced handheld spectroscopic eye-safe technology for point-of-care neurodiagnostic
Traumatic brain injury (TBI), a major cause of morbidity and mortality worldwide, is hard to diagnose at the point of care with patients often exhibiting no clinical symptoms. There is an urgent need for rapid point-of-care diagnostics to enable timely intervention. We have developed a technology for rapid acquisition of molecular fingerprints of TBI biochemistry to safely measure proxies for cerebral injury through the eye, providing a path toward noninvasive point-of-care neurodiagnostics using simultaneous Raman spectroscopy and fundus imaging of the neuroretina. Detection of endogenous neuromarkers in porcine eyes' posterior revealed enhancement of high-wave number bands, clearly distinguishing TBI and healthy cohorts, classified via artificial neural network algorithm for automated data interpretation. Clinically, translating into reduced specialist support, this markedly improves the speed of diagnosis. Designed as a hand-held cost-effective technology, it can allow clinicians to rapidly assess TBI at the point of care and identify long-term changes in brain biochemistry in acute or chronic neurodiseases.</p
Mesenchymal stromal cell-mediated neuroprotection and functional preservation of retinal ganglion cells in a rodent model of glaucoma
Background aims: Glaucoma is a leading cause of irreversible blindness involving loss of retinal ganglion cells (RGC). Mesenchymal stromal cells (MSC) have shown promise as a paracrine-mediated therapy for compromised neurons. It is, however, unknown whether dental pulp stem cells (DPSC) are effective as a cellular therapy in glaucoma and how their hypothesized influence compares with other more widely researched MSC sources. The present study aimed to compare the efficacy of adipose-derived stem cells, bone marrow-derived MSC (BMSC) and DPSC in preventing the loss of RGC and visual function when transplanted into the vitreous of glaucomatous rodent eyes. Methods: Thirty-five days after raised intraocular pressure (IOP) and intravitreal stem cell transplantation, Brn3a+ RGC numbers, retinal nerve fibre layer thickness (RNFL) and RGC function were evaluated by immunohistochemistry, optical coherence tomography and electroretinography, respectively. Results: Control glaucomatous eyes that were sham-treated with heat-killed DPSC had a significant loss of RGC numbers, RNFL thickness and function compared with intact eyes. BMSC and, to a greater extent, DPSC provided significant protection from RGC loss and RNFL thinning and preserved RGC function. Discussion: The study supports the use of DPSC as a neuroprotective cellular therapy in retinal degenerative disease such as glaucoma
Improving corneal permeability of dexamethasone using penetration enhancing agents:First step towards achieving topical drug delivery to the retina
With an ever-increasing burden of vision loss caused by diseases of the posterior ocular segment, there is an unmet clinical need for non-invasive treatment strategies. Topical drug application using eye drops suffers from low to negligible bioavailability to the posterior segment as a result of static and dynamic defensive ocular barriers to penetration, while invasive delivery systems are expensive to administer and suffer potentially severe complications. As the cornea is the main anatomical barrier to uptake of topically applied drugs from the ocular surface, we present an approach to increase corneal permeability of a corticosteroid, dexamethasone sodium-phosphate (DSP), using a novel penetration enhancing agent (PEA). We synthesised a novel polyacetylene (pAc) polymer and compared its activity to two previously described cell penetrating peptide (CPP) based PEAs, TAT and penetratin, with respect to increasing transcorneal permeability of DSP in a rapid ex-vivo porcine corneal assay over 60 min. The transcorneal apparent permeability coefficients (Papp) for diffusion of pAc, and fluorescein isothiocyanate (FITC) conjugated TAT and penetratin were up to 5 times higher (p < 0.001), when compared to controls. When pAc was used in formulation with DSP, an almost 5-fold significant increase was observed in Papp of DSP across the cornea (p = 0.0130), a significant 6-fold increase with TAT (p = 0.0377), and almost 7-fold mean increase with penetratin (p = 0.9540). Furthermore, we investigated whether the PEAs caused any irreversible damage to the barrier integrity of the corneal epithelium by measuring transepithelial electrical resistance (TEER) and immunostaining of tight junction proteins using zonula occludens-1 (ZO-1) and occludin antibodies. There was no damage or structural toxicity, and the barrier integrity was preserved after PEA application. Finally, an in-vitro cytotoxicity assessment of all PEAs in human retinal pigment epithelium cells (ARPE-19) demonstrated that all PEAs were very well-tolerated, with IC50 values of 64.79 mM for pAc and 1335.45 µM and 87.26 µM for TAT and penetratin, respectively. Our results suggest that this drug delivery technology could potentially be used to achieve a significantly higher intraocular therapeutic bioavailability after topical eye drop administration, than currently afforded
Improving corneal permeability of dexamethasone using penetration enhancing agents:First step towards achieving topical drug delivery to the retina
With an ever-increasing burden of vision loss caused by diseases of the posterior ocular segment, there is an unmet clinical need for non-invasive treatment strategies. Topical drug application using eye drops suffers from low to negligible bioavailability to the posterior segment as a result of static and dynamic defensive ocular barriers to penetration, while invasive delivery systems are expensive to administer and suffer potentially severe complications. As the cornea is the main anatomical barrier to uptake of topically applied drugs from the ocular surface, we present an approach to increase corneal permeability of a corticosteroid, dexamethasone sodium-phosphate (DSP), using a novel penetration enhancing agent (PEA). We synthesised a novel polyacetylene (pAc) polymer and compared its activity to two previously described cell penetrating peptide (CPP) based PEAs, TAT and penetratin, with respect to increasing transcorneal permeability of DSP in a rapid ex-vivo porcine corneal assay over 60 min. The transcorneal apparent permeability coefficients (Papp) for diffusion of pAc, and fluorescein isothiocyanate (FITC) conjugated TAT and penetratin were up to 5 times higher (p < 0.001), when compared to controls. When pAc was used in formulation with DSP, an almost 5-fold significant increase was observed in Papp of DSP across the cornea (p = 0.0130), a significant 6-fold increase with TAT (p = 0.0377), and almost 7-fold mean increase with penetratin (p = 0.9540). Furthermore, we investigated whether the PEAs caused any irreversible damage to the barrier integrity of the corneal epithelium by measuring transepithelial electrical resistance (TEER) and immunostaining of tight junction proteins using zonula occludens-1 (ZO-1) and occludin antibodies. There was no damage or structural toxicity, and the barrier integrity was preserved after PEA application. Finally, an in-vitro cytotoxicity assessment of all PEAs in human retinal pigment epithelium cells (ARPE-19) demonstrated that all PEAs were very well-tolerated, with IC50 values of 64.79 mM for pAc and 1335.45 µM and 87.26 µM for TAT and penetratin, respectively. Our results suggest that this drug delivery technology could potentially be used to achieve a significantly higher intraocular therapeutic bioavailability after topical eye drop administration, than currently afforded
TGF-β-induced IOP elevations are mediated by RhoA in the early but not the late fibrotic phase of open angle glaucoma
Optical coherence tomography angiography analysis methods:a systematic review and meta-analysis
Optical coherence tomography angiography (OCTA) is widely used for non-invasive retinal vascular imaging, but the OCTA methods used to assess retinal perfusion vary. We evaluated the different methods used to assess retinal perfusion between OCTA studies. MEDLINE and Embase were searched from 2014 to August 2021. We included prospective studies including ≥ 50 participants using OCTA to assess retinal perfusion in either global retinal or systemic disorders. Risk of bias was assessed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. Heterogeneity of data was assessed by Q statistics, Chi-square test, and I2 index. Of the 5974 studies identified, 191 studies were included in this evaluation. The selected studies employed seven OCTA devices, six macula volume dimensions, four macula subregions, nine perfusion analyses, and five vessel layer definitions, totalling 197 distinct methods of assessing macula perfusion and over 7000 possible combinations. Meta-analysis was performed on 88 studies reporting vessel density and foveal avascular zone area, showing lower retinal perfusion in patients with diabetes mellitus than in healthy controls, but with high heterogeneity. Heterogeneity was lowest and reported vascular effects strongest in superficial capillary plexus assessments. Systematic review of OCTA studies revealed massive heterogeneity in the methods employed to assess retinal perfusion, supporting calls for standardisation of methodology
Decorin reduces intraocular pressure and retinal ganglion cell loss in rodents through fibrolysis of the scarred trabecular meshwork
Purpose. To investigate whether Decorin, a matrikine that regulates extracellular matrix (ECM) deposition, can reverse established trabecular meshwork (TM) fibrosis, lower IOP, and reduce progressive retinal ganglion cell (RGC) death in a novel rodent model of TM fibrosis. Methods. Adult rats had intracameral (IC) injections of human recombinant (hr) TGF-β over 30 days (30d; to induce TM fibrosis, raise IOP, and initiate RGC death by 17d) or PBS (controls) and visually evoked potentials (VEP) were measured at 30d to evaluate resultant visual pathway dysfunction. In some animals TGF-β injections were stopped at 17d when TM fibrosis and IOP were consistently raised and either hrDecorin or PBS IC injections were administered between 21d and 30d. Intraocular pressure was measured biweekly and eyes were processed for immunohistochemical analysis of ECM deposition to assess TM fibrosis and levels of matrix metalloproteinases (MMP) and tissue inhibitors of matrix metalloproteinases (TIMP) to assess fibrolysis. The effect of hrDecorin treatment on RGC survival was also assessed. Results. Transforming growth factor–β injections caused sustained increases in ECM deposition in the TM and raised IOP by 17d, responses that were associated with 42% RGC loss and a significant decrease in VEP amplitude measured at 30d. Decorin treatment from 17d reduced TGF-β–induced TM fibrosis, increased levels of MMP2 and MMP9 and lowered TIMP2 levels, and lowered IOP, preventing progressive RGC loss. Conclusions. Human recombinant Decorin reversed established TM fibrosis and lowered IOP, thereby rescuing RGC from progressive death. These data provide evidence for the candidacy of hrDecorin as a treatment for open-angle glaucoma
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