13 research outputs found
Post-traumatic vancomycin-resistant enterococcal endophthalmitis
The emergence of antibiotic-resistant organisms among severe ocular infections is of grave concern. We describe the first reported case of vancomycin-resistant enterococcal endophthalmitis following ocular trauma, uniquely caused by Enterococcus gallinarum. The organism demonstrated intrinsic resistance to ceftazidime and vancomycin but responded favorably to a combination of intravitreal and intravenous ampicillin, plus intravitreal amikacin. When faced with a multidrug-resistant organism, the ophthalmologist must consider alternative antibiotic strategies
The impact of axial length on retinal tamponade for gas, silicone oil, and heavy silicone oil, using an in vitro model
Background: To investigate whether ocular axial length influences the tamponade efficacy of three commonly used agents: gas, silicone oil, and heavy silicone oil. Methods: A series of filling experiments was conducted using 19-mm and 25-mm surface-modified spherical model eye chambers to mimic the vitreous cavity. For each agent, tamponade efficacy was assessed across a range of percentage fills, and comparison was made between the two model eye chambers. The behavior of each tamponade agent was quantified by measuring (1) the maximum height of the tamponade bubble, and calculating (2) the arc of retinal contact subtended by the tamponade bubble. Results: Polynomial regression analysis found no statistically significant difference between the regression models for the different-sized model eye chambers for bubble height or arc of retinal contact subtended. This applied to all of the tamponade agents under investigation. Conclusions: Across the range of cavity sizes under investigation, no significant difference in tamponade efficacy (as reflected by the measured dimensions of the tamponade bubble) was identified. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Response to: ‘Utility of digitally assisted vitreoretinal surgery systems (DAVS) for high volume vitreoretinal surgery centres: a pilot study’
A randomised controlled trial evaluating internal limiting membrane peeling forceps in macular hole surgery
PurposeTo assess study design and a range of anatomical and functional changes after internal limiting membrane (ILM) peeling using forceps developed for atraumatic ILM pick-up compared to standard forceps.MethodsWe conducted a masked proof-of concept randomised controlled trial (RCT) on 65 patients who underwent ILM peeling for idiopathic full-thickness macular hole (FTMH) using etched-tip forceps (etched-tip group, 33 eyes) compared to standard ILM forceps (smooth-tip group, 32 eyes). Patients were assessed preoperatively, 3 weeks, 3 and 6 months postoperatively.ResultsThe primary closure rate was 95.4%. There was no statistically significant difference between the groups in terms of final visual acuity (66.9 vs 70.9 ETDRS letters, p = 0.13), difference of visual field mean deviation (1.32 vs 1.14 decibels), and number of eyes with pick-up-related retinal haemorrhages (16% vs 16%, p = 0.96), swelling of arcuate nerve fibre layer lesions (63% vs 55%, p = 0.54), number of dissociated optic nerve fibre layer lesions (31.4 vs 41.0, p = 0.16), nor inner retina defects (37% vs 22%, p = 0.17). Similar changes in inner retinal volumes were detected in all 9 sectors of an ETDRS grid except for a trend (p = 0.06) towards a lower reduction in the inferior inner sector in the etched-tip group.ConclusionsThe study was successfully completed with masking maintained and a low risk of bias. Multiple endpoints relating to ILM peeling were assessed, and estimates were provided that can be used for future studies. Although the study was not powered to assess any specific endpoint, the anatomical and functional outcomes assessed did not significantly differ
Heavy silicone oil: A "novel" intraocular tamponade agent
Advances in vitreoretinal surgery have greatly increased the anatomical re-attachment rate in cases with proliferative vitreoretinopathy. Intraocular tamponade agents have been in use by vitreoretinal surgeons for nearly a century. The effectiveness of an internal agent relies on its ability to make contact with the internal surface of the vitreous cavity. In the short term, this is controlled by the agent's specific gravity and interfacial tensions. In the long term, the viscosity of the material is critical to maintaining its integrity and thus reducing dispersion. The commonly used tamponade agents such as perfluoropropane (C3F8), sulfur hexafluoride (SF6), and silicone oil are "lighter than water" hence, float upward in the aqueous. A consequence of this is that in the upright position the superior retina is very well supported, leaving the inferior retina less well so. More recently, there has been interest in the development of "heavier than water" long-term tamponade agents that sink in the eye. Heavy silicone oil is a transparent, homogenous solution of two substances used as a single tamponade agent with improved properties and a specific gravity greater than water. Densiron (one of the two available heavy silicone oil's) is a mixture of perfluorohexyloctane (F6H8, with a specific gravity of 1.35 g/ml and viscosity of 2.5 mPas), and conventional silicone oil (specific gravity of 0.97 g/ml and viscosity of 5700 mPas depending on the molecular weight). The specific gravity of Densiron is 1.06 g/ml and the viscosity is 1400 mPas, making it a novel heavier-than-water, long-term internal tamponade agent, which means that in the upright position it sinks and provides support for the inferior retina. Copyright © 2011 American Academy of Optometry.link_to_subscribed_fulltex
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International Classification System for Ocular Complications of Anti-Vascular Endothelial Growth Factor Agents in Clinical Trials
Complications associated with intravitreal anti-vascular endothelial growth factor (VEGF) therapies are inconsistently reported in the literature, thus limiting an accurate evaluation and comparison of safety between studies. This study aimed to develop a standardized classification system for anti-VEGF ocular complications using the Delphi consensus process.
Systematic review and Delphi consensus process.
25 international retinal specialists participated in the Delphi consensus survey.
A systematic literature search was conducted to identify complications of intravitreal anti-VEGF agent administration based on randomized controlled trials (RCTs) of anti-VEGF therapy. A comprehensive list of complications was derived from these studies, and this list was subjected to iterative Delphi consensus surveys involving international retinal specialists that voted on inclusion, exclusion, rephrasing, and addition of complications. As well, surveys determined specifiers for the selected complications. This iterative process helped refine the final classification system.
The proportion of retinal specialists who choose to include or exclude complications associated with anti-VEGF administration.
After screening 18,229 articles, 130 complications were initially categorized from 145 included RCTs. Participant consensus via the Delphi method resulted in the inclusion of 91 (70%) complications after three rounds. After incorporating further modifications made based on participant suggestions, such as rewording certain phrases and combining similar terms, 24 redundant complications were removed, leaving a total of 67 (52%) complications in the final list. A total of 14 (11%) complications met exclusion thresholds and were eliminated by participants across both rounds. All other remaining complications not meeting inclusion or exclusion thresholds were also excluded from the final classification system after the Delphi process terminated. In addition, 47 out of 75 (63%) proposed complication specifiers were included based on participant agreement.
Using the Delphi consensus process, a comprehensive, standardized classification system consisting of 67 ocular complications and 47 unique specifiers was established for intravitreal anti-VEGF agents in clinical trials. The adoption of this system in future trials could improve consistency and quality of adverse event reporting, potentially facilitating more accurate risk-benefit analyses