Novel classification system for management of rhegmatogenous retinal detachment with minimally invasive detachment surgery: a network meta-analysis of randomized trials focused on patient-centred outcomes

OBJECTIVE

To describe a novel classification system for primary rhegmatogenous retinal detachment (RRD) based on level 1 evidence assessing the functional outcomes of repair techniques with the goal of using a minimally invasive detachment surgery.

METHODS

A systematic review and network meta-analysis of randomized, controlled trials comparing pneumatic retinopexy (PnR), scleral buckle (SB), or pars plana vitrectomy (PPV) for RRD was conducted. Primary outcomes were best-corrected visual acuity (BCVA), metamorphopsia, and operative complications. A meta-analysis was performed with a random effects maximum likelihood model, with outcomes of standardized mean difference (SMD) or risk ratio (RR) and 95% confidence interval. Inclusion and exclusion criteria were assessed to inform a classification system.

RESULTS

Fourteen trials were included. RRDs were classified from categories 1-3 based on configuration (simple to complex). There was no significant difference in final BCVA between PnR and PPV (categories 1 and 2; SMD = -0.10, 95% CI -0.24 to 0.04), nor was a final BVCA difference found between SB and PPV (SMD = 0.01, 95% CI -0.05 to 0.08), combined SB + PPV and PPV (SMD = 0.02, 95% CI -0.08 to 0.12), or combined SB + PPV and SB (SMD = 0.01, 95% CI -0.11 to 0.12). SB had an elevated risk of choroidal detachment (RR = 5.17, 95% CI 1.68-15.97), hypotony (RR = 12.26, 95% CI 1.63-92.04), and strabismus or diplopia (RR = 5.86, 95% CI 1.04-32.91) compared with PPV but a lower risk of iatrogenic breaks (RR = 0.08, 95% CI 0.02-0.43). Vertical metamorphopsia scores were superior for PnR over PPV at 12 months (Pneumatic Retinopexy versus Vitrectomy for the Management of Primary Rhegmatogenous Retinal Detachment Outcomes Randomized Trial, p = 0.026).

CONCLUSION

This novel classification system may be useful for future trials assessing morphologic categories of RRD in a systematic manner. Minimally invasive detachment surgery may allow for trials to focus on maximizing functional outcomes while minimizing morbidity.

Changes in aqueous and vitreous inflammatory cytokine levels in proliferative diabetic retinopathy: a systematic review and meta-analysis

BACKGROUND

Diabetic retinopathy is a major complication of diabetes mellitus, where in its most advanced form ischemic changes lead to the development of retinal neovascularization, termed proliferative diabetic retinopathy (PDR). While the development of PDR is often associated with angiogenic and inflammatory cytokines, studies differ on which cytokines are implicated in disease pathogenesis and on the strength of these associations. We therefore conducted a systematic review and meta-analysis to quantitatively assess the existing body of data on intraocular cytokines as biomarkers in PDR.

METHODS

A comprehensive search of the literature without year limitation was conducted to January 18, 2021, which identified 341 studies assessing vitreous or aqueous cytokine levels in PDR, accounting for 10379 eyes with PDR and 6269 eyes from healthy controls. Effect sizes were calculated as standardized mean differences (SMD) of cytokine concentrations between PDR and control patients.

RESULTS

Concentrations (SMD, 95% confidence interval, and p-value) of aqueous IL-1β, IL-6, IL-8, MCP-1, TNF-α, and VEGF, and vitreous IL-2, IL-4, IL-6, IL-8, angiopoietin-2, eotaxin, erythropoietin, GM-CSF, GRO, HMGB-1, IFN-γ, IGF, IP-10, MCP-1, MIP-1, MMP-9, PDGF-AA, PlGF, sCD40L, SDF-1, sICAM-1, sVEGFR, TIMP, TNF-α, and VEGF were significantly higher in patients with PDR when compared to healthy nondiabetic controls. For all other cytokines no differences, failed sensitivity analyses or insufficient data were found.

CONCLUSIONS

This extensive list of cytokines speaks to the complexity of PDR pathogenesis, and informs future investigations into disease pathogenesis, prognosis, and management.

A Stepwise Approach to the Surgical Management of Hemorrhagic Choroidal Detachments

Purpose:

This work describes a stepwise surgical approach to draining choroidal detachments and 2 cases for which this approach was used.

Methods:

The first step involves insertion of an anterior chamber maintainer and a nonvalved 23- or 25-gauge trocar cannula at the highest peak of hemorrhagic choroidal detachment (as determined using B-scan ultrasonography), 6 to 8 mm from and angled 20° to 30° toward the limbus. The second step involves removal of the trocar to expose the sclerotomy. Alternatively, the second step can be insertion of a second trocar. The third step involves the creation of a small focal peritomy around the preexisting sclerotomy and enlargement of the preexisting sclerotomy into a radial sclerotomy. Progression between steps only occurs if prior steps did not provide adequate drainage.

Results:

Two cases of appositional hemorrhagic choroidal detachments in hypotonic eyes were successfully resolved by this stepwise approach. In case 1, a choroidal detachment developed after a corneal ulcer perforation. The hemorrhagic choroidal detachment in case 1 was resolved with steps 1 and 2, and an unnecessary scleral cutdown was avoided. In case 2, a choroidal detachment developed after a trabeculectomy. The detachment in case 2 required progression to step 3, extension of the trocar insertion site into a radial sclerotomy.

Conclusions:

This stepwise approach should be considered to reduce excessive manipulation of the globe and conjunctiva in hemorrhagic and serous choroidal detachments that warrant surgical intervention.

Changes in aqueous and vitreous inflammatory cytokine levels in diabetic macular oedema: a systematic review and meta-analysis

Diabetic macular oedema (DME) is considered a chronic inflammatory disease associated with aberrations in many intraocular cytokines. Studies assessing the role of these cytokines as biomarkers in the diagnosis and management of DME have demonstrated inconsistent findings. We quantitatively summarized data related to 116 candidate aqueous and vitreous inflammatory cytokines as biomarkers in DME. A systematic search without year limitation was performed up to 19 October 2020. Studies were included if they provided data on aqueous or vitreous cytokine concentrations in patients with DME. Effect sizes were generated as standardized mean differences (SMDs) of cytokine concentrations between patients with DME and controls. Data were extracted from 128 studies that included 4163 study eyes with DME and 1281 control eyes. Concentrations (standard mean difference, 95% confidence interval and p-value) of aqueous IL-6 (1.28, 0.57-2.00, p = 0.004), IL-8 (1.06, 0.74-1.39, p < 0.00001), MCP-1 (1.36, 0.57-2.16, p = 0.0008) and VEGF (1.31, 1.01-1.62, p < 0.00001) and vitreous VEGF (2.27, 1.55-2.99, p < 0.00001) were significantly higher in patients with DME (n = 4163) compared to healthy controls (n = 1281). No differences, failed sensitivity analyses or insufficient data were found between patients with DME and healthy controls for the concentrations of the remaining cytokines. This analysis implicates multiple cytokine biomarker candidates other than VEGF in DME and clarifies previously reported inconsistent associations. As the therapeutic options for DME expand to include multiple agents with multiple targets, it will be critical to manage the treatment burden with tailored therapy that optimizes outcomes and minimizes treatment burden. Intraocular cytokines have the promise of providing a robust individualized assessment of disease status and response to therapy. We have identified key candidate cytokines that may serve as biomarkers in individualized treatment algorithms.

Optimizing Color Performance of the Ngenuity 3-Dimensional Visualization System

Purpose

To evaluate the effect of surgeon-controlled parameters on the color performance of the Ngenuity 3-dimensional (3D) visualization system.

Design

A calibrated reference target was placed inside a model eye to assess the Ngenuity 3D camera under different settings. The Ngenuity 3D display was assessed with a commercial colorimeter.

Methods

Manufacturer-recommended methodology for white balancing was compared against all common deviations in technique. Following white balance, images of a calibrated reference target were extracted and tested using Imatest Master software to calculate quantitative color differences (delta E and delta C). The Ngenuity monitor was assessed using a SpyderX Elite commercial colorimeter to assess for image burn-in by quantifying color uniformity and maximum luminescence.

Main Outcome Measures

Delta E and delta C were calculated for all variables. Color uniformity and luminance were assessed in candelas per square meter (nits).

Results

Color performance using the manufacturer-recommended specifications yielded a delta E of 12.81 ± 1.67. Changing the white balance target to a videography grey card (P = 0.07) and 4 × 4 gauze (P = 0.37) provided similar performance, whereas using white computer paper or the operator’s palm significantly increased the delta E from 12.81 ± 1.67 to 15.28 ± 1.22 (P = 0.01) and 17.71 ± 2.03 (P < 0.01), respectively. Changes to card position, magnification, stability, or ambient lighting did not significantly impact white balance results, whereas having the card in crisp focus did decrease color accuracy (15.78 ± 1.63; P = 0.03). Minor improvement in performance occurred when the laser filter was off for white balance and image acquisition (9.28 ± 0.25; P < 0.01), but deterioration occurred if the laser filter was placed after balancing (16.59 ± 1.17; P < 0.01). Both light sources of 23-gauge light pipe at 34% intensity and 25-gauge chandelier at 50% intensity gave similar color accuracy (P = 0.37). When comparing different Ngenuity machines, color uniformity and maximum luminescence decreased with increased device use.

Conclusions

Overall, the Ngenuity 3D has robust color performance. A few limitations of both the camera and monitor were identified, and surgeons should be aware of these pitfalls as well as solutions examined herein to mitigate their effects during surgery.

Changes in aqueous and vitreous inflammatory cytokine levels in neovascular age-related macular degeneration: a systematic review and meta-analysis

Inflammatory cytokines are involved in the pathogenesis of neovascular age-related macular degeneration (nAMD) and have been shown to be useful as diagnostic and predictive biomarkers. Given the heterogeneity of data within the literature, we aimed to quantitatively summarize data related to inflammatory cytokines in nAMD. A systematic search without year limitation was performed up to 13 April 2020. Studies were included if they provided data on aqueous or vitreous cytokine concentrations in patients with nAMD. Data were extracted from 95 studies that encompassed 3105 study eyes with nAMD and 1209 control eyes. Effect sizes were generated as standardized mean differences (SMDs) of cytokine concentrations between patients with nAMD and controls. Among the 4314 eyes in 95 studies, aqueous concentrations (standard mean difference, 95% confidence interval and p-value) of MCP-1 (0.43, 0.09 to 0.77 and p = 0.01), MIG (0.63, 0.31 to 0.94 and p = 0.0001), TGF-β (0.45, 0.07 to 0.82 and p = 0.02) and VEGF (0.64, 0.31 to 0.98 and p = 0.0001) were significantly higher in patients with nAMD compared to healthy controls. No differences, failed sensitivity analyses or insufficient data were found between patients with nAMD and healthy controls for the concentrations of the remaining cytokines and with all vitreous samples. Previous studies had shown conflicting associations with nAMD for all 27 cytokines assessed. Our analysis indicates multiple candidate cytokines other than VEGF that are implicated in nAMD and adds clarity to the previous literature. This will help focus translational research in nAMD investigating biomarkers and therapeutic targets.

Noninfectious endophthalmitis following intravitreal triamcinolone acetonide: clinical case and literature review

OBJECTIVE

To review the literature on noninfectious endophthalmitis (NIE) following intravitreal triamcinolone acetonide (IVTA).

DESIGN

A literature review and case report.

PARTICIPANTS

Individuals who developed NIE after IVTA injection.

METHODS

A review of the literature was undertaken using Ovid MEDLINE and EMBASE databases, and articles available up to and including December 30, 2019, were included. A total of 518 articles were identified, of which 27 were selected. We also present an illustrative case report.

RESULTS

The incidence rate of NIE lies between 0.1% and 7.3% in most studies. Although the etiology of NIE is still the subject of investigation, proposed mechanisms include excipients and rheologic stress caused by small crystals. The time to presentation of NIE is often 1-3 days after IVTA injection, with symptoms of moderate to marked reduction in visual acuity along with signs of anterior chamber inflammatory reaction, hypopyon, and vitritis. Resolution occurs in 1-3 weeks in the majority of patients, and almost all return to their pre-injection visual acuity. Differences in the presentations of NIE, infectious endophthalmitis, and pseudo-endophthalmitis are discussed. We also present an illustrative case report of an 80-year-old woman who developed NIE after an IVTA injection for cystoid macular edema.

CONCLUSIONS

It is important to distinguish NIE from other forms of endophthalmitis because they have different natural histories and require different interventions and follow-up. NIE is rarely accompanied by significant pain or conjunctival erythema. Visual acuity is inconsistently affected and is therefore not a good criterion for identifying the type of presenting endophthalmitis.

Changes in Aqueous and Vitreous Inflammatory Cytokine Levels in Retinal Vein Occlusion: A Systematic Review and Meta-analysis

Purpose:

Evidence suggests that inflammatory cytokines not only play a role in the pathogenesis of retinal vein occlusion (RVO) but also may be useful as biomarkers to predict disease severity and response to treatment. We aimed to quantitatively summarize data on inflammatory cytokines associated with RVO.

Methods:

A systematic search of peer-reviewed English-language articles was performed without year limitation up to August 19, 2019. Studies were included if they provided data on aqueous or vitreous cytokine concentrations in patients with RVO. Data were extracted from 116 studies that encompassed 3242 study eyes with RVO and 1402 control eyes. Effect sizes were generated as standardized mean differences (SMDs) of cytokine concentrations between patients with RVO vs controls.

Results:

Among the 4644 eyes in 116 studies, aqueous and vitreous concentrations (SMD, 95% CI, and P value) of interleukin (IL)-6 (aqueous: 1.23, 0.65 to 1.81, P < .001 vitreous: 0.70, 0.49 to 0.90, P < .001), IL-8 (aqueous: 1.11, 0.73 to 1.49, P < .001; vitreous: 1.19, 0.73 to 1.65, P < .001), monocyte chemoattractant protein 1(aqueous: 1.22, 0.72 to 1.72, P < .001; vitreous 1.42, 0.92 to 1.91, P < .001), vascular endothelial growth factor (VEGF) (aqueous: 1.52, 1.09 to 1.94, P < .001; vitreous: 0.99, 0.78 to 1.21, P < .001) were significantly higher in patients with RVO than in healthy controls. Only aqueous concentrations of IL-10 (0.81, 0.45 to 1.18, P < .001), angiopoietin 4 (1.96, 0.92 to 3.00, P < .001), and platelet-derived growth factor (PDGF)-AA (0.82, 0.35 to 1.30, P < .001) were significantly higher in patients with RVO than in healthy controls. Only the vitreous concentration of soluble intercellular adhesion molecule-1 (sICAM-1) (1.23, 0.83 to 1.63, P < .001) was significantly higher in patients with RVO. No differences, failed sensitivity analyses, or insufficient data were found between patients with RVO and healthy controls for the concentrations of the remaining cytokines.

Conclusions:

Several cytokines in addition to VEGF have the potential to be useful biomarkers and therapeutic targets in RVO.

Ice nucleation by particles containing long-chain fatty acids of relevance to freezing by sea spray aerosols

Heterogeneous ice nucleation in the atmosphere regulates cloud properties, such as phase (ice versus liquid) and lifetime. Aerosol particles of marine origin are relevant ice nucleating particle sources when marine aerosol layers are lifted over mountainous terrain and in higher latitude ocean boundary layers, distant from terrestrial aerosol sources. Among many particle compositions associated with ice nucleation by sea spray aerosols are highly saturated fatty acids. Previous studies have not demonstrated their ability to freeze dilute water droplets. This study investigates ice nucleation by monolayers at the surface of supercooled droplets and as crystalline particles at temperatures exceeding the threshold for homogeneous freezing. Results show the poor efficiency of long chain fatty acid (C16, C18) monolayers in templating freezing of pure water droplets and seawater subphase to temperatures of at least -30 °C, consistent with theory. This contrasts with freezing of fatty alcohols (C22 used here) at nearly 20 °C warmer. Evaporation of μL-sized droplets to promote structural compression of a C19 acid monolayer did not favor warmer ice formation of drops. Heterogeneous ice nucleation occurred for nL-sized droplets condensed on 5 to 100 μm crystalline particles of fatty acid (C12 to C20) at a range of temperatures below -28 °C. These experiments suggest that fatty acids nucleate ice at warmer than -36 °C only when the crystalline phase is present. Rough estimates of ice active site densities are consistent with those of marine aerosols, but require knowledge of the proportion of surface area comprised of fatty acids for application.

Immersion freezing of supermicron mineral dust particles: freezing results, testing different schemes for describing ice nucleation, and ice nucleation active site densities

Ice nucleation on mineral dust particles is known to be an important process in the atmosphere. To accurately implement ice nucleation on mineral dust particles in atmospheric simulations, a suitable theory or scheme is desirable to describe laboratory freezing data in atmospheric models. In the following, we investigated ice nucleation by supermicron mineral dust particles [kaolinite and Arizona Test Dust (ATD)] in the immersion mode. The median freezing temperature for ATD was measured to be approximately -30 °C compared with approximately -36 °C for kaolinite. The freezing results were then used to test four different schemes previously used to describe ice nucleation in atmospheric models. In terms of ability to fit the data (quantified by calculating the reduced chi-squared values), the following order was found for ATD (from best to worst): active site, pdf-α, deterministic, single-α. For kaolinite, the following order was found (from best to worst): active site, deterministic, pdf-α, single-α. The variation in the predicted median freezing temperature per decade change in the cooling rate for each of the schemes was also compared with experimental results from other studies. The deterministic model predicts the median freezing temperature to be independent of cooling rate, while experimental results show a weak dependence on cooling rate. The single-α, pdf-α, and active site schemes all agree with the experimental results within roughly a factor of 2. On the basis of our results and previous results where different schemes were tested, the active site scheme is recommended for describing the freezing of ATD and kaolinite particles. We also used our ice nucleation results to determine the ice nucleation active site (INAS) density for the supermicron dust particles tested. Using the data, we show that the INAS densities of supermicron kaolinite and ATD particles studied here are smaller than the INAS densities of submicron kaolinite and ATD particles previously reported in the literature.

The prevalence of retinopathy in men with Type 2 diabetes and obstructive sleep apnoea

AIMS

To clarify the relationship between obstructive sleep apnoea (OSA) and diabetic retinopathy.

RESEARCH DESIGN AND METHODS

A cohort of 240 men from primary and secondary care previously participated in a study on the prevalence of OSA in Type 2 diabetes and provided anthropometric information, details of their diabetes, had glycated haemoglobin (HbA1c) measured and overnight oximetry performed. They were re-contacted for permission to review their routine screening clinical retinal photographs, which were then scored by a trained grader, providing detailed retinopathy, maculopathy and photocoagulation scores.

RESULTS

One hundred and eighteen men both consented and had retinal photographs available to review. Of these, 24% had OSA, with mean+/-sd 4% oxygen saturation (SaO2) dips/h of 20.9+/-16.6 vs. 2.8+/-2.1 in the non-OSA group. As expected, the OSA group had a significantly higher mean body mass index of 31.9+/-5.2 vs. 28.5+/-5.1 kg/m2 and neck size 44.5+/-3.6 vs. 41.9+/-2.5 cm, but the two groups did not differ significantly in age, diabetes duration, diabetes treatment, HbA1c, smoking history or proportion with known hypertension. Retinopathy and maculopathy scores were significantly worse in the OSA group (P<0.0001). Multiple regression analysis showed only OSA (R2=0.19, P<0.0001) and HbA1c (R2=0.04, P=0.03) to be significant independent predictors of retinopathy. OSA was the only independent significant predictor of the total microaneurysm score (R2=0.21, P=0.004), a detailed retinopathy subclassification. OSA was the only independent significant predictor of maculopathy (R2=0.3, P<0.001).

CONCLUSION

In men with Type 2 diabetes, there is a strong association between retinopathy and OSA, independent of conventional retinopathy risk factors.