28 research outputs found
Effect of Porocentesis Upon the Blood-Aqueous Barrier of Cynomolgus Monkeys
Anterior chamber paracentesis disrupts the blood aqueous barrier (BAB) of rabbits and nonhuman primates, but the magnitude and duration of breakdown in monkeys has not been clarified. We have studied anterior chamber paracentesis in cynomolgus monkeys as a potential model of postoperative BAB breakdown. The effect of a single paracentesis upon fluorescein sodium concentration in the anterior chamber after an intravenous injection was measured in 16 eyes of 8 animals. In an additional 10 eyes of 5 animals, aqueous humor was withdrawn for analysis 24 hours and one week following paracentesis. Anterior chamber fluorescein concentration was 57 ± 22 ng/ml (mean ± standard deviation) before paracentesis, rose to 81 ± 47 ng/ml 24 hrs after paracentesis, and was 60 ± 36 ng/ml at 72-96 hours. Twenty-four hours after paracentesis, total protein concentration was elevated, but ascorbic acid and transforming growth factor-jS levels were not. Paracentesis in monkeys has only a small and short lasting effect upon BAB integrity and is therefore unlikely to be a good model for assessing the effect of agents designed to stabilize the BAB. However, the short-lived effect of paracentesis may permit the repetitive collection of "primary aqueous" for physiologic and biochemical studies. Invest Ophthalmol Vis Sci 33:165-171, 199
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Elevated intraocular pressure, pigment dispersion and dark hypopyon in endogenous endophthalmitis from Listeria monocytogenes
Listeria monocytogenes endophthalmitis occurred in an immunologically competent patient with no identifiable extraocular septic focus. The patient presented with a dark hypopyon and markedly elevated intraocular pressure, and the diagnosis was established by culture and histopathologic examination of ocular fluid. Four of the fourteen reported cases of
Listeria monocytogenes endophthalmitis also presented with a dark hypopyon, and all cases had markedly elevated intraocular pressure. The presence of a dark hypopyon and elevated intraocular pressure may indicate endogenous intraocular infection with
Listeria monocytogenes, even in an apparently healthy host
Dependability of results in conference abstracts of randomized controlled trials in ophthalmology and author financial conflicts of interest as a factor associated with full publication.
BackgroundDiscrepancies between information in conference abstracts and full publications describing the same randomized controlled trial have been reported. The association between author conflicts of interest and the publication of randomized controlled trials is unclear. The objective of this study was to use randomized controlled trials in ophthalmology to evaluate (1) the agreement in the reported main outcome results by comparing abstracts and corresponding publications and (2) the association between the author conflicts of interest and publication of the results presented in the abstracts.MethodsWe considered abstracts describing results of randomized controlled trials presented at the 2001-2004 Association for Research in Vision and Ophthalmology conferences as eligible for our study. Through electronic searching and by emailing abstract authors, we identified the earliest publication (journal article) containing results of each abstract's main outcome through November 2013. We categorized the discordance between the main outcome results in the abstract and its paired publication as qualitative (a difference in the direction of the estimated effect) or as quantitative. We used the Association for Research in Vision and Ophthalmology categories for conflicts of interest: financial interest, employee of business with interest, consultant to business with interest, inventor/developer with patent, and receiving ≥ 1 gift from industry in the past year. We calculated the relative risks (RRs) of publication associated with the categories of conflicts of interest for abstracts with results that were statistically significant, not statistically significant, or not reported.ResultsWe included 513 abstracts, 230 (44.8 %) of which reached publication. Among the 86 pairs with the same main outcome domain at the same time point, 47 pairs (54.7 %) had discordant results: qualitative discordance in 7 pairs and quantitative discordance in 40 pairs. Quantitative discordance was indicated as < 10, 10-20, > 20 %, and unclear in 14, 5, 14, and 7 pairs, respectively. First authors reporting of one or more conflicts of interest was associated with a greater likelihood of publication (RR = 1.31; 95 % CI = 1.04 to 1.64) and a shorter time-to-publication (log-rank p = 0.026). First author conflicts of interests that were associated with publication were financial support (RR = 1.50; 95 % CI = 1.19 to 1.90) and one or more gifts (RR = 1.42; 95 % CI = 1.05 to 1.92). The association between conflicts of interest and publication remained, irrespective of the statistical significance of the results.ConclusionsMore than half the abstract/publication pairs exhibited some amount of discordance in the main outcome results, calling into question the dependability of conference abstracts. Regardless of the main outcome results, the conflicts of interests of the abstract's first author were associated with publication
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Novel Glaucoma Procedures A Report by the American Academy of Ophthalmology
Objective: To review the published literature and summarize clinically relevant information about novel, or emerging, surgical techniques for the treatment of open-angle glaucoma and to describe the devices and procedures in proper context of the appropriate patient population, theoretic effects, advantages, and disadvantages.
Design: Devices and procedures that have US Food and Drug Administration clearance or are currently in phase III clinical trials in the United States are included: the Fugo blade (Medisurg Ltd., Norristown, PA), Ex-PRESS mini glaucoma shunt (Alcon, Inc., Hunenberg, Switzerland), SOLX Gold Shunt (SOLX Ltd., Boston, MA), excimer laser trabeculotomy (AIDA, Glautec AG, Nurnberg, Germany), canaloplasty (iScience Interventional Corp., Menlo Park, CA), trabeculotomy by internal approach (Trabectome, NeoMedix, Inc., Tustin, CA), and trabecular micro-bypass stent (iStent, Glaukos Corporation, Laguna Hills, CA).
Methods: Literature searches of the PubMed and the Cochrane Library databases were conducted up to October 2009 with no date or language restrictions.
Main Outcome Measures: These searches retrieved 192 citations, of which 23 were deemed topically relevant and rated for quality of evidence by the panel methodologist. All studies but one, which was rated as level II evidence, were rated as level III evidence.
Results: All of the devices studied showed a statistically significant reduction in intraocular pressure and, in some cases, glaucoma medication use. The success and failure definitions varied among studies, as did the calculated rates. Various types and rates of complications were reported depending on the surgical technique. On the basis of the review of the literature and mechanism of action, the authors also summarized theoretic advantages and disadvantages of each surgery.
Conclusions: The novel glaucoma surgeries studied all show some promise as alternative treatments to lower intraocular pressure in the treatment of open-angle glaucoma. It is not possible to conclude whether these novel procedures are superior, equal to, or inferior to surgery such as trabeculectomy or to one another. The studies provide the basis for future comparative or randomized trials of existing glaucoma surgical techniques and other novel procedures
Laser Trabeculoplasty for Open-Angle Glaucoma
Objective: To provide an evidence-based summary of the outcomes, repeatability, and safety of laser trabeculoplasty for open-angle glaucoma.
Methods: A search of the peer-reviewed literature in the PubMed and the Cochrane Library databases was conducted in June 2008 and was last repeated in March 2010 with no date or language restrictions. The search yielded 637 unique citations, of which 145 were considered to be of possible clinical relevance for further review and were included in the evidence analysis.
Results: Level I evidence indicates an acceptable long-term efficacy of initial argon laser trabeculoplasty for open-angle glaucoma compared with initial medical treatment. Among the remaining studies, level II evidence supports the efficacy of selective laser trabeculoplasty for lowering intraocular pressure for patients with open-angle glaucoma. Level III evidence supports the efficacy of repeat use of laser trabeculoplasty.
Conclusions: Laser trabeculoplasty is successful in lowering intraocular pressure for patients with open-angle glaucoma. At this time, there is no literature establishing the superiority of any particular form of laser trabeculoplasty. The theories of action of laser trabeculoplasty are not elucidated fully. Further research into the differences among the lasers used in trabeculoplasty, the repeatability of the procedure, and techniques of treatment is necessary.
Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references. Ophthalmology 2011;118:2296-2302 (C) 2011 by the American Academy of Ophthalmology
Assessment of visual function in glaucoma: a report by the American Academy of Ophthalmology
To review the published literature to summarize and evaluate the effectiveness of visual function tests in diagnosing glaucoma and in monitoring progression.
Literature searches of the PubMed and Cochrane Library databases were conducted last on May 7, 2010, and were restricted to citations published on or after January 1, 1994. The search yielded 1063 unique citations. The first author reviewed the titles and abstracts of these articles and selected 185 of possible clinical relevance for further review. The panel members reviewed the full text of these articles and determined that 85 met inclusion criteria. They conducted data abstraction of the 85 studies, and the panel methodologist assigned a level of evidence to each of the selected articles. One study was rated as level I evidence. The remaining articles were classified broadly as providing level II evidence. Studies deemed to provide level III evidence were not included in the assessment.
Standard white-on-white automated perimetry remains the most commonly performed test for assessing the visual field, with the Swedish interactive threshold algorithm (SITA) largely replacing full-threshold testing strategies. Frequency-doubling technology and its refinement into Matrix perimetry, as well as short-wavelength automated perimetry, now available with SITA, have been evaluated extensively. Machine learning classifiers seem to be ready for incorporation into software to help distinguish glaucomatous from nonglaucomatous fields. Other technologies, such as multifocal visual-evoked potential and electroretinography, which were designed as objective measures of visual function, provide testing free of patient input, but issues prevent their adoption for glaucoma management.
Advances in technology and analytic tools over the past decade have provided us with more rapid and varied ways of assessing visual function in glaucoma, but they have yet to produce definitive guidance on the diagnosis of glaucoma or its progression over time. Further research on an objective measure of visual function is needed
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Aqueous shunts in glaucoma: a report by the American Academy of Ophthalmology
OBJECTIVETo provide an evidence-based summary of commercially available aqueous shunts currently used in substantial numbers (Ahmed [New World Medical, Inc., Rancho Cucamonga, CA], Baerveldt [Advanced Medical Optics, Inc., Santa Ana, CA], Krupin [Eagle Vision, Inc, Memphis, TN], Molteno [Molteno Ophthalmic Ltd., Dunedin, New Zealand]) to control intraocular pressure (IOP) in various glaucomas.METHODSSeventeen previously published randomized trials, 1 prospective nonrandomized comparative trial, 1 retrospective case-control study, 2 comprehensive literature reviews, and published English language, noncomparative case series and case reports were reviewed and graded for methodologic quality.RESULTSAqueous shunts are used primarily after failure of medical, laser, and conventional filtering surgery to treat glaucoma and have been successful in controlling IOP in a variety of glaucomas. The principal long-term complication of anterior chamber tubes is corneal endothelial failure. The most shunt-specific delayed complication is erosion of the tube through overlying conjunctiva. There is a low incidence of this occurring with all shunts currently available, and it occurs most frequently within a few millimeters of the corneoscleral junction after anterior chamber insertion. Erosion of the equatorial plate through the conjunctival surface occurs less frequently. Clinical failure of the various devices over time occurs at a rate of approximately 10% per year, which is approximately the same as the failure rate for trabeculectomy.CONCLUSIONSBased on level I evidence, aqueous shunts seem to have benefits (IOP control, duration of benefit) comparable with those of trabeculectomy in the management of complex glaucomas (phakic or pseudophakic eyes after prior failed trabeculectomies). Level I evidence indicates that there are no advantages to the adjunctive use of antifibrotic agents or systemic corticosteroids with currently available shunts. Too few high-quality direct comparisons of various available shunts have been published to assess the relative efficacy or complication rates of specific devices beyond the implication that larger-surface-area explants provide more enduring and better IOP control. Long-term follow-up and comparative studies are encouraged