Managing diabetic macular edema in clinical practice: systematic review and meta-analysis of current strategies and treatment options

Purpose: This meta-analysis aims to summarize 12-month best-corrected visual acuity (BCVA) outcomes in response to anti-vascular endothelial growth factor (VEGF) therapy and dexamethasone implant for the treatment of diabetic macular edema (DME) and to identify factors affecting treatment response using evidence generated from metaregression. Methods: A systematic review of electronic databases was conducted to identify randomized controlled trials (RCTs) and real-life/observational studies that reported 12-month changes in BCVA in patients with DME on anti-VEGF or dexamethasone implant treatment in monotherapy. Study factors that were analyzed are baseline patient characteristics, study type, drug employed, number of injections and 12-month change in BCVA. Data were pooled in a random-effects meta-analysis with BCVA change as the main outcome. Meta-regression was conducted to assess the impact of multiple covariates. Results: One-hundred-five heterogeneous study populations (45,032 eyes) were identified and included in the analysis. The use of anti-VEGFs and dexamethasone implant induced an overall increase of +8.13 ETDRS letters in BCVA at 12 months of follow-up. Metaregression provided evidence that mean BCVA change using anti-VEGFs was not statistically higher for RCTs (p=0.35) compared to observational studies. Dexamethasone implant showed a trend for better results in observational studies over RCTs. Populations following a fixed aflibercept regimen performed better than those following a reactive treatment regimen. Mean BCVA gain was higher in younger populations (p<0.001), with lower baseline BCVA (p<0.0001) and longer diabetes duration (p<0.0001), receiving a higher number of injections (p<0.0001). Conclusion: Intravitreal therapy with anti-VEGFs or dexamethasone implant produces a significant improvement in BCVA at 12 months in patients with DME. Meta-regression identified the modifiable covariates that can be targeted in order to maximize functional results

Infection control measures in ophthalmology during the COVID-19 outbreak: A narrative review from an early experience in Italy

Introduction: The novel coronavirus (SARS-CoV-2) is infecting people and spreading easily from person-to-person. Cases have been detected in most countries worldwide. Italy is one of the most affected countries as of 30 March 2020. Public health response includes a rapid reorganization of the Italian National Healthcare System in order to reduce transmission of COVID-19 within hospitals and healthcare facilities, while optimizing the assistance to patients with severe COVID-19 complications. Methods: We analysed the actions that were taken in three ophthalmology centres in northern Italy during the SARS-CoV-2 outbreak and how these measures affected patient\u2019s attendance. In addition, due to the rapidly evolving scenario, we reviewed the evidence available during the course of this pandemic. Results: A full reorganization of ophthalmology services is mandatory according to current existing infection containment measures in order to continue dispensing urgent procedures without endangering the community with amplification of the diffusion chain. Ophthalmologists are considered at elevated risk of exposure when caring patients and vice versa, due to their close proximity during eye examination. High volumes of procedures typically generated by ophthalmologists with concurrent implications on the risk of infection are considered when re-assessing healthcare facilities reorganization. Conclusion: Containment measures in the event of pandemic due to infective agents should be well known by healthcare professionals and promptly applied in order to mitigate the risk of nosocomial transmission and outbreak

Scleral fixation of a single-piece foldable acrylic IOL through a 1.80 mm corneal incision

A new scleral fixation technique of a single-piece acrylic foldable intraocular lens (IOL) (enVista MX60, Bausch & Lomb, Inc.) through a 1.80 mm corneal incision, using the IOL eyelets as anchoring point, is described. It was a retrospective review of 26 cases. The preoperative mean corrected distance visual acuity was 0.51 \ub1 0.21 logarithm of the minimum angle of resolution (logMAR). It improved significantly to 0.25 \ub1 0.27 logMAR (P < .01), 0.18 \ub1 0.16 logMAR (P < .01), and 0.17 \ub1 0.16 logMAR (P < .01) (at 1 month, 3 months, and 6 months postoperatively, respectively, repeated measures analysis of variance, P < .0001). No astigmatism increase of more than 0.75 diopters was recorded at any time point. In all 26 patients, the IOL was well centered and stable for the entire monitoring period. No complications were observed during follow-up. Scleral fixation of the foldable IOL through a 1.80 mm corneal incision provided excellent IOL stability during the 6-month follow-up of this study and might be an effective and safe surgical technique

Efficient hybrid solar cells based on solution processed mesoporous TiO2 / Tin (II) sulfide heterojunctions

Tin monosulfide (SnS) is emerging as a promising absorber material for the development of low-cost, solution-processable solar cells. Herein, we present a straightforward, solution-based route for the preparation of tin monosulfide (SnS) films employing a green solvent, namely, tetrahydrofuran (THF). We show that the surface coverage and the morphology of the SnS films can be tuned by modification of the precursor solution composition and film deposition conditions. Furthermore, we explore the effect of a PEDOT:PSS interlayer and fabricate solar cells based on the following architecture: FTO/planar-TiO2/mesoporous-TiO2/SnS/P3HT/PEDOT:PSS/Ag. Devices based on this architecture are shown to exhibit power conversion efficiencies (PCEs) of 3.0%, thus demonstrating the potential of our method for the development of low-cost and environmentally friendly solar cells

A High Deuterium Abundance at z=0.7

Of the light elements, the primordial abundance of deuterium, (D/H)_p, provides the most sensitive diagnostic for the cosmological mass density parameter Omega_B. Recent high redshift (D/H) measurements are highly discrepant, although this may reflect observational uncertainties. The larger (D/H) values, which imply a low Omega_B and require the Universe to be dominated by non-baryonic matter (dynamical studies indicate a higher total density parameter), cause problems for galactic chemical evolution models since they have difficulty in reproducing the large decline down to the lower present-day (D/H). Conversely, low (D/H) values imply an Omega_B greater than derived from ^7Li and ^4He abundance measurements, and may require a deuterium abundance evolution that is too low to easily explain. Here we report the first measurement at intermediate redshift, where the observational difficulties are smaller, of a gas cloud with ideal characteristics for this experiment. Our analysis of the z = 0.7010 absorber toward 1718+4807 indicates (D/H) = 2.0 +/- 0.5 x 10^{-4} which is in the high range. This and other independent observations suggests there may be a cosmological inhomogeneity in (D/H)_p of at least a factor of ten.Comment: 6 pages, 1 figur

A z=5.34 Galaxy Pair in the Hubble Deep Field

We present spectrograms of the faint V-drop (V(606) = 28.1, I(814) = 25.6) galaxy pair HDF3-951.1 and HDF3-951.2 obtained at the Keck II Telescope. Fernandez-Soto, Lanzetta, & Yahil (1998) derive a photometric redshift of z(ph) = 5.28 (+0.34,-0.41; 2 sigma) for these galaxies; our integrated spectrograms show a large and abrupt discontinuity near 7710 (+- 5) Angstroms. This break is almost certainly due to the Lyman alpha forest as its amplitude (1 - fnu(short) / fnu(long) > 0.87; 95% confidence limit) exceeds any discontinuities observed in stellar or galaxian rest-frame optical spectra. The resulting absorption-break redshift is z=5.34 (+- 0.01). Optical/near-IR photometry from the HDF yields an exceptionally red (V(606)-I(814)) color, consistent with this large break. A more accurate measure of the continuum depression blueward of Lyman alpha utilizing the imaging photometry yields D(A) = 0.88. The system as a whole is slightly brighter than L*(1500) relative to the z~3 Lyman break population and the total star formation rate inferred from the UV continuum is ~22 h(50)^-2 M(sun) yr^-1 (q(0) = 0.5) assuming the absence of dust extinction. The two individual galaxies are quite small (size scales < 1 h(50)^-1 kpc). Thus these galaxies superficially resemble the Pascarelle etal (1996) ``building blocks''; if they comprise a gravitationally bound system, the pair will likely merge in a time scale ~100 Myr.Comment: 18 pages, 4 figures; accepted to A

On ionisation effects and abundance ratios in damped Lyman-alpha systems

The similarity between observed velocity structures of Al III and singly ionised species in damped Lyman-alpha systems (DLAs) suggests the presence of ionised gas in the regions where most metal absorption lines are formed. To explore the possible implications of ionisation effects we construct a simplified two-region model for DLAs consisting of an ionisation bounded region with an internal radiation field and a neutral region with a lower metal content. Within this framework we find that ionisation effects are important. If taken into account, the element abundance ratios in DLAs are quite consistent with those observed in Milky Way stars and in metal-poor H II regions in blue compact dwarf galaxies. In particular we cannot exclude the same primary N origin in both DLAs and metal-poor galaxies. From our models no dust depletion of heavy elements needs to be invoked; little depletion is however not excluded.Comment: to appear in "Evolution of Galaxies. I. Observational clues", Eds. J.M. Vilchez, G. Stasinska, Astrophysics and Space Science, in press. 5 pages, including 3 figure

Improved Charge Separation and Photovoltaic Performance of BiI3 Absorber Layers by Use of an In Situ Formed BiSI Interlayer

Stable and nontoxic bismuth iodide (BiI3) is emerging as a promising absorber material for solar cell applications as it possesses favorable optical properties such as a narrow bandgap (1.7 eV) and a high absorption coefficient (105 cm–1) in the visible region. Despite these promising features, solar cells employing this material have only achieved power conversion efficiencies in the region of 1% as of yet, which is distant from the theoretical efficiency limit of 28%. It is reasonable to suppose that the relatively low performance of BiI3-based solar cells may originate from very short carrier lifetimes (180–240 ps) in BiI3, which makes efficient separation of mobile charges a crucial factor for the improvement of the photovoltaic performance of this material. Herein, transient optical spectroscopy is employed to show that the use of a bismuth sulfide iodide interlayer between the electron transport layer (ETL) and the bismuth iodide absorber promotes efficient charge separation. On the basis of this knowledge, we report BiI3 solar cells with a power conversion efficiency of 1.21% using a solar cell architecture comprised of ITO/SnO2/BiSI/BiI3/organic HTM/Au