210 research outputs found

    Bronchial to subclavian shunt in a CF patient. A potential pitfall for embolization

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    Bronchial artery embolization is a well accepted and widely used technique in the management of massive haemoptysis in cystic fibrosis (CF). It can be a complex procedure requiring a deep knowledge of the bronchial artery anatomy including the possible bronchial anastomoses. We report a case of complex vascular anatomy of the left bronchial artery with multiple anastomoses with the ipsilateral subclavian artery as cause of non-attempted embolization. \ua9 2003 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved

    Persistent or Recurrent Diabetic Macular Edema After Fluocinolone Acetonide 0.19 mg Implant: Risk Factors and Management

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    Purpose: To investigate baseline characteristics of patients undergoing additional antivascular endothelial growth factor (VEGF) injections for residual or recurrent diabetic macular edema (DME) in the first year after 0.19-mg fluocinolone acetonide (FAc) implant. Design: Prospective cohort study. Methods: Ninety-four eyes of 66 patients received an FAc implant. Eyes with persistent or recurrent DME were managed with pro re nata anti-VEGF agents. Demographic data and medical history were collected at baseline. Best-corrected visual acuity and central macular thickness were measured every 2 months. The 3 outcomes explored were 1) the risk factors for administration of additional anti-VEGF agents, 2) the interval from FAc to first anti-VEGF injection; and 3) the number of anti-VEGF doses required to maintain regression of DME. Results: Eighteen eyes (19.1%) of 13 patients received 1.3 ± 0.6 anti-VEGF injections. These eyes had significantly thicker central macular thickness at baseline and over the entire follow-up period (P < .001); best-corrected visual acuity was similar at every time point to eyes that were not receiving extra DME treatments. Eyes without preexistent panretinal photocoagulation (PRP) had a higher risk to undergo supplemental treatments (hazard ratio 1.5 [95% confidence interval 1.1-2.5, P = .03). The interval between FAc implant and the first anti-VEGF had a significant linear positive relationship with the number of dexamethasone implants before FAc implant (P = .002, R2 = 0.47). No association was found between baseline factors and the number of injections given. Conclusion: Anti-VEGF agents are efficient treatment to maintain visual acuity in residual/recurrent DME after FAc. Patients with higher baseline central macular thickness and with no previous central macular thickness are more likely to require additional treatments to control DME

    Validating Trend-Based End Points for Neuroprotection Trials in Glaucoma

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    Purpose: The purpose of this study was to evaluate the power of trend-based visual field (VF) progression end points against long-term development of event-based end points accepted by the US Food and Drug Administration (FDA). Methods: One eye from 3352 patients with ≥10 24-2 VFs (median = 11 years) follow-up were analyzed. Two FDA-compatible criteria were applied to these series to label “true-progressed” eyes: ≥5 locations changing from baseline by more than 7 dB (FDA-7) or by more than the expected test-retest variability (GPA-like) in 2 consecutive tests. Observed rates of progression (RoP) were used to simulate trial-like series (2 years) randomly assigned (1000 times) to a “placebo” or a “treatment” arm. We simulated neuroprotec-tive “treatment” effects by changing the proportion of “true progressed” eyes in the two arms. Two trend-based methods for mean deviation (MD) were assessed: (1) linear mixed model (LMM), testing average difference in RoP between the two arms, and (2) time-to-progression (TTP), calculated by linear regression as time needed for MD to decline by predefined cutoffs from baseline. Power curves with 95% confidence intervals were calculated for trend and event-based methods on the simulated series. Results: The FDA-7 and GPA-like progression was achieved by 45% and 55% of the eyes in the clinical database. LMM and TTP had similar power, significantly superior to the event-based methods, none of which reached 80% power. All methods had a 5% false-positive rate. Conclusions: The trend-based methods can efficiently detect treatment effects defined by long-term FDA-compatible progression. Translational Relevance: The assessment of the power of trend-based methods to detect clinically relevant progression end points

    Estimating the Distribution of True Rates of Visual Field Progression in Glaucoma

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    Purpose: The purpose of this study was to estimate the distribution of the true rates of progression (RoP) of visual field (VF) loss. . Methods: We analyzed the progression of mean deviation over time in series of ≥ 10 tests from 3352 eyes (one per patient) from 5 glaucoma clinics, using a novel Bayesian hierarchical Linear Mixed Model (LMM); this modeled the random-effect distribution of RoPs as the sum of 2 independent processes following, respectively, a negative exponential distribution (the "true" distribution of RoPs) and a Gaussian distribution (the "noise"), resulting in a skewed exGaussian distribution. The exGaussian-LMM was compared to a standard Gaussian-LMM using the Watanabe-Akaike Information Criterion (WAIC). The random-effect distributions were compared to the empirical cumulative distribution function (eCDF) of linear regression RoPs using a Kolmogorov-Smirnov test. Results: The WAIC indicated a better fit with the exGaussian-LMM (estimate [standard error]: 192174.4 [721.2]) than with the Gaussian-LMM (192595 [697.4], with a difference of 157.2 [22.6]). There was a significant difference between the eCDF and the Gaussian-LMM distribution (P < 0.0001), but not with the exGaussian-LMM distribution (P = 0.108). The estimated mean (95% credible intervals, CIs) "true" RoP (-0.377, 95% CI = -0.396 to -0.359 dB/year) was more negative than the observed mean RoP (-0.283, 95% CI = -0.299 to -0.268 dB/year), indicating a bias likely due to learning in standard LMMs. Conclusions: The distribution of "true" RoPs can be estimated with an exGaussian-LMM, improving model accuracy. Translational Relevance: We used these results to develop a fast and accurate analytical approximation for sample-size calculations in clinical trials using standard LMMs, which was integrated in a freely available web application

    OCT Angiography (OCTA) in Retinal Diagnostics

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    Optical coherence tomography angiography (OCTA) is an imaging modality which can be applied in ophthalmology to provide detailed visualization of the perfusion of vascular networks in the eye. Compared to previous state of the art dye-based imaging, such as fluorescein angiography, OCTA is non-invasive, time-efficient, and it allows for the examination of retinal vasculature in 3D. These advantages of the technique combined with the good usability in commercial devices led to a quick adoption of the new modality in the clinical routine. However, the interpretation of OCTA data is not without problems: Commonly observed image artifacts and the quite involved algorithmic details of OCTA signal construction can make the clinical assessment of OCTA exams challenging. In this article we describe the technical background of OCTA and discuss the data acquisition process, common image visualization techniques, as well as limitations and sources of artifacts of the modality. Examples of clinical cases underline the increasing importance of the OCTA technology in ophthalmology and its relation to dye-based angiography
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