Intraretinal Hyper-Reflective Foci Are Almost Universally Present and Co-Localize With Intraretinal Fluid in Diabetic Macular Edema

Purpose

In diabetic macular edema (DME), hyper-reflective foci (HRF) has been linked to disease severity and progression. Using an automated approach, we aimed to investigate the baseline distribution of HRF in DME and their co-localization with cystoid intraretinal fluid (IRF).

Methods

Baseline spectral-domain optical coherence tomography (SD-OCT) volume scans (N = 1527) from phase III clinical trials YOSEMITE (NCT03622580) and RHINE (NCT03622593) were segmented using a deep-learning-based algorithm (developed using B-scans from BOULEVARD NCT02699450) to detect HRF. The HRF count and volume were assessed. HRF distributions were analyzed in relation to best-corrected visual acuity (BCVA), central subfield thickness (CST), and IRF volume in quartiles, and Diabetic Retinopathy Severity Scores (DRSS) in groups. Co-localization of HRF with IRF was calculated in the central 3-mm diameter using the en face projection.

Results

HRF were present in most patients (up to 99.7%). Median (interquartile range [IQR]) HRF volume within the 3-mm diameter Early Treatment Diabetic Retinopathy Study ring was 1964.3 (3325.2) pL, and median count was 64.0 (IQR = 96.0). Median HRF volumes were greater with decreasing BCVA (nominal P = 0.0109), and increasing CST (nominal P < 0.0001), IRF (nominal P < 0.0001), and DRSS up to very severe nonproliferative diabetic retinopathy (nominal P < 0.0001). HRF co-localized with IRF in the en face projection.

Conclusions

Using automated HRF segmentation of full SD-OCT volumes, we observed that HRF are a ubiquitous feature in DME and exhibit relationships with BCVA, CST, IRF, and DRSS, supporting a potential link to disease severity. The spatial distribution of HRF closely followed that of IRF.

TENAYA and LUCERNE: Two-Year Results from the Phase 3 Neovascular Age-Related Macular Degeneration Trials of Faricimab with Treat-and-Extend Dosing in Year 2

PURPOSE

To evaluate 2-year efficacy, durability, and safety of the bispecific antibody faricimab, which inhibits both angiopoietin-2 and VEGF-A.

DESIGN

TENAYA (ClinicalTrials.gov identifier, NCT03823287) and LUCERNE (ClinicalTrials.gov identifier, NCT03823300) were identically designed, randomized, double-masked, active comparator-controlled phase 3 noninferiority trials.

PARTICIPANTS

Treatment-naive patients with neovascular age-related macular degeneration (nAMD) 50 years of age or older.

METHODS

Patients were randomized (1:1) to intravitreal faricimab 6.0 mg up to every 16 weeks (Q16W) or aflibercept 2.0 mg every 8 weeks (Q8W). Faricimab fixed dosing based on protocol-defined disease activity at weeks 20 and 24 up to week 60, followed up to week 108 by a treat-and-extend personalized treatment interval regimen.

MAIN OUTCOME MEASURES

Efficacy analyses included change in best-corrected visual acuity (BCVA) from baseline at 2 years (averaged over weeks 104, 108, and 112) and proportion of patients receiving Q16W, every 12 weeks (Q12W), and Q8W dosing at week 112 in the intention-to-treat population. Safety analyses included ocular adverse events (AEs) in the study eye through study end at week 112.

RESULTS

Of 1326 patients treated across TENAYA/LUCERNE, 1113 (83.9%) completed treatment (n = 555 faricimab; n = 558 aflibercept). The BCVA change from baseline at 2 years was comparable between faricimab and aflibercept groups in TENAYA (adjusted mean change, +3.7 letters [95% confidence interval (CI), +2.1 to +5.4] and +3.3 letters [95% CI, +1.7 to +4.9], respectively; mean difference, +0.4 letters [95% CI, -1.9 to +2.8]) and LUCERNE (adjusted mean change, +5.0 letters [95% CI, +3.4 to +6.6] and +5.2 letters [95% CI, +3.6 to +6.8], respectively; mean difference, -0.2 letters [95% CI, -2.4 to +2.1]). At week 112 in TENAYA and LUCERNE, 59.0% and 66.9%, respectively, achieved Q16W faricimab dosing, increasing from year 1, and 74.1% and 81.2%, achieved Q12W or longer dosing. Ocular AEs in the study eye were comparable between faricimab and aflibercept groups in TENAYA (55.0% and 56.5% of patients, respectively) and LUCERNE (52.9% and 47.5% of patients, respectively) through week 112.

CONCLUSIONS

Treat-and-extend faricimab treatment based on nAMD disease activity maintained vision gains through year 2, with most patients achieving extended dosing intervals.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Efficacy and Safety of Faricimab for Macular Edema due to Retinal Vein Occlusion: 24-Week Results from the BALATON and COMINO Trials

PURPOSE

To evaluate the 24-week efficacy and safety of the dual angiopoietin-2 (Ang-2) and vascular endothelial growth factor (VEGF)-A inhibitor faricimab versus aflibercept in patients with vein occlusion.

DESIGN

Phase 3, global, randomized, double-masked, active comparator-controlled trials: BALATON/COMINO (ClincalTrials.gov identifiers: NCT04740905/NCT04740931; sites: 149/192).

PARTICIPANTS

Patients with treatment-naïve foveal center-involved macular edema resulting from branch (BALATON) or central or hemiretinal (COMINO) RVO.

METHODS

Patients were randomized 1:1 to faricimab 6.0 mg or aflibercept 2.0 mg every 4 weeks for 24 weeks.

MAIN OUTCOME MEASURES

Primary end point: change in best-corrected visual acuity (BCVA) from baseline to week 24. Efficacy analyses included patients in the intention-to-treat population. Safety analyses included patients who received ≥ 1 doses of study drug.

RESULTS

Enrollment: BALATON, n = 553; COMINO, n = 729. The BCVA gains from the baseline to week 24 with faricimab were noninferior versus aflibercept in BALATON (adjusted mean change, +16.9 letters [95.03% confidence interval (CI), 15.7-18.1 letters] vs. +17.5 letters [95.03% CI, 16.3-18.6 letters]) and COMINO (+16.9 letters [95.03% CI, 15.4-18.3 letters] vs. +17.3 letters [95.03% CI, 15.9-18.8 letters]). Adjusted mean central subfield thickness reductions from the baseline were comparable for faricimab and aflibercept at week 24 in BALATON (-311.4 μm [95.03% CI, -316.4 to -306.4 μm] and -304.4 μm [95.03% CI, -309.3 to -299.4 μm]) and COMINO (-461.6 μm [95.03% CI, -471.4 to -451.9 μm] and -448.8 μm [95.03% CI, -458.6 to -439.0 μm]). A greater proportion of patients in the faricimab versus aflibercept arm achieved absence of fluorescein angiography-based macular leakage at week 24 in BALATON (33.6% vs. 21.0%; nominal P = 0.0023) and COMINO (44.4% vs. 30.0%; nominal P = 0.0002). Faricimab was well tolerated, with an acceptable safety profile comparable with aflibercept. The incidence of ocular adverse events was similar between patients receiving faricimab (16.3% [n = 45] and 23.0% [n = 84] in BALATON and COMINO, respectively) and aflibercept (20.4% [n = 56] and 27.7% [n = 100], respectively).

CONCLUSIONS

These findings demonstrate the efficacy and safety of faricimab, a dual Ang-2/VEGF-A inhibitor, in patients with macular edema secondary to retinal vein occlusion.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Population Pharmacokinetics of Ranibizumab Delivered via the Port Delivery System Implanted in the Eye in Patients with Neovascular Age-Related Macular Degeneration

The port delivery system with ranibizumab (PDS) is designed to continuously deliver ranibizumab to maintain therapeutic drug concentrations in the vitreous of the eye for an extended duration. The PDS has been evaluated for the treatment of neovascular age-related macular degeneration in the Ladder (PDS 10, 40, and 100 mg/mL, with refill exchanges as needed, versus monthly intravitreal ranibizumab 0.5 mg), Archway (PDS 100 mg/mL with 24-week refill exchanges, versus monthly intravitreal ranibizumab 0.5 mg), and ongoing Portal (PDS 100 mg/mL with 24-week refill exchanges) clinical trials. Data from Ladder, Archway, and Portal were used to develop a population pharmacokinetics (PK) model to estimate the ranibizumab release rate from the PDS implant, describe ranibizumab PK in serum and aqueous humor, and predict the concentration in vitreous humor. A model was developed to adequately describe the serum and aqueous humor PK data, as suggested by goodness-of-fit plots as well as visual predictive checks. In the final model, the first-order implant release rate was estimated to be 0.00654 (1/day), corresponding to a half-life of 106 days, consistent with the implant release rate determined in vitro. The model-predicted vitreous concentrations achieved with PDS 100 mg/mL given every 24 weeks were below the intravitreal peak concentration and above the intravitreal trough concentration of ranibizumab over the entire 24-week refill interval. The results demonstrate a durable release of ranibizumab from the PDS with a half-life of 106 days, providing vitreous exposure to ranibizumab for at least 24 weeks that is within the range of exposure for monthly intravitreal treatment.

BALATON and COMINO: Phase III Randomized Clinical Trials of Faricimab for Retinal Vein Occlusion: Study Design and Rationale

Purpose

Dual inhibition of angiopoietin-2 and VEGF-A with faricimab (Vabysmo) offers excellent visual acuity gains with strong durability in patients with diabetic macular edema (ME) and neovascular age-related macular degeneration. The phase III BALATON/COMINO (NCT04740905/NCT04740931) trials will investigate the efficacy, safety, and durability of faricimab in patients with ME due to retinal vein occlusion (RVO).

Design

Two identically designed global, randomized, double-masked, active comparator-controlled studies.

Participants

Anti-VEGF treatment-naive patients with branch, central, or hemiretinal RVO.

Methods

Patients were randomized to 6 monthly injections of faricimab 6.0 mg or aflibercept 2.0 mg. From weeks 24 to 72, all patients received faricimab 6.0 mg administered in up to 16-week intervals using an automated treatment algorithm to generate a treat-and-extend-based personalized treatment interval dosing regimen. Personalized treatment interval adjustments were based on changes in central subfield thickness (CST) and best-corrected visual acuity (BCVA).

Main Outcome Measures

Primary end point was noninferiority of faricimab versus aflibercept in mean change from baseline in BCVA (week 24; noninferiority margin: 4 letters). Secondary end points (weeks 0-24) were mean change from baseline in BCVA, CST, and National Eye Institute Visual Function Questionnaire 25 composite score; proportion of patients gaining or avoiding loss of ≥ 15/≥ 10/≥ 5/> 0 letters. Secondary end points (weeks 24-72) were treatment durability (week 68); continuation of weeks 0 to 24 end points. Ocular/nonocular adverse events will be assessed.

Results

In total, 1282 patients across 22 countries were enrolled (BALATON, 553 patients, 149 centers; COMINO, 729 patients, 193 centers).

Conclusions

Using a novel automated interval algorithm, BALATON/COMINO will evaluate the efficacy and safety of faricimab for ME secondary to RVO and provide key insights into how to personalize treatment.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Management of Key Ocular Adverse Events in Patients Implanted with the Port Delivery System with Ranibizumab

PURPOSE

To provide strategies for the management of key ocular adverse events (AEs) that may be encountered with the Port Delivery System with ranibizumab (PDS) in practice and provide recommendations that may mitigate such AEs based on clinical trial experiences and considerations from experts in the field.

DESIGN

Safety evaluation based on the phase 2 Ladder (NCT02510794) and phase 3 Archway (NCT03677934) trials of the PDS.

METHODS

The PDS implant is a permanent, indwelling, and refillable ocular drug delivery system that requires standardized procedural steps for its insertion and refill-exchange procedures, which evolved during the PDS clinical program. We described identified AEs that may arise after implant insertion or refill-exchange procedures, including conjunctival retraction, conjunctival erosion, endophthalmitis, implant dislocation, conjunctival blebs or conjunctival filtering bleb leaks, wound leaks, hypotony, choroidal detachment, vitreous hemorrhage, rhegmatogenous retinal detachment, cataract, and septum dislodgement.

RESULTS

Adverse events related to the PDS were well understood, were manageable by trial investigators, and did not prevent patients from achieving optimal outcomes in most cases.

CONCLUSIONS

Surgeons using the PDS should be aware of potential ocular AEs and identify them early for optimal management. As with any new surgical procedure, it is important to provide surgeons with appropriate training, ensure adherence to optimal surgical techniques, and continually refine the procedure to mitigate complications and improve outcomes.

Efficacy, durability, and safety of intravitreal faricimab with extended dosing up to every 16 weeks in patients with diabetic macular oedema (YOSEMITE and RHINE): two randomised, double-masked, phase 3 trials

BACKGROUND

To reduce treatment burden and optimise patient outcomes in diabetic macular oedema, we present 1-year results from two phase 3 trials of faricimab, a novel angiopoietin-2 and vascular endothelial growth factor-A bispecific antibody.

METHODS

YOSEMITE and RHINE were randomised, double-masked, non-inferiority trials across 353 sites worldwide. Adults with vision loss due to centre-involving diabetic macular oedema were randomly assigned (1:1:1) to intravitreal faricimab 6·0 mg every 8 weeks, faricimab 6·0 mg per personalised treatment interval (PTI), or aflibercept 2·0 mg every 8 weeks up to week 100. PTI dosing intervals were extended, maintained, or reduced (every 4 weeks up to every 16 weeks) based on disease activity at active dosing visits. The primary endpoint was mean change in best-corrected visual acuity at 1 year, averaged over weeks 48, 52, and 56. Efficacy analyses included the intention-to-treat population (non-inferiority margin 4 Early Treatment Diabetic Retinopathy Study [ETDRS] letters); safety analyses included patients with at least one dose of study treatment. These trials are registered with ClinicalTrials.gov (YOSEMITE NCT03622580 and RHINE NCT03622593).

FINDINGS

3247 patients were screened for eligibility in YOSEMITE (n=1532) and RHINE (n=1715). After exclusions, 940 patients were enrolled into YOSEMITE between Sept 5, 2018, and Sept 19, 2019, and 951 patients were enrolled into RHINE between Oct 9, 2018, and Sept 20, 2019. These 1891 patients were randomly assigned to faricimab every 8 weeks (YOSEMITE n=315, RHINE n=317), faricimab PTI (n=313, n=319), or aflibercept every 8 weeks (n=312, n=315). Non-inferiority for the primary endpoint was achieved with faricimab every 8 weeks (adjusted mean vs aflibercept every 8 weeks in YOSEMITE 10·7 ETDRS letters [97·52% CI 9·4 to 12·0] vs 10·9 ETDRS letters [9·6 to 12·2], difference -0·2 ETDRS letters [-2·0 to 1·6]; RHINE 11·8 ETDRS letters [10·6 to 13·0] vs 10·3 ETDRS letters [9·1 to 11·4] letters, difference 1·5 ETDRS letters [-0·1 to 3·2]) and faricimab PTI (YOSEMITE 11·6 ETDRS letters [10·3 to 12·9], difference 0·7 ETDRS letters [-1·1 to 2·5]; RHINE 10·8 ETDRS letters [9·6 to 11·9], difference 0·5 ETDRS letters [-1·1 to 2·1]). Incidence of ocular adverse events was comparable between faricimab every 8 weeks (YOSEMITE n=98 [31%], RHINE n=137 [43%]), faricimab PTI (n=106 [34%], n=119 [37%]), and aflibercept every 8 weeks (n=102 [33%], n=113 [36%]).

INTERPRETATION

Robust vision gains and anatomical improvements with faricimab were achieved with adjustable dosing up to every 16 weeks, demonstrating the potential for faricimab to extend the durability of treatment for patients with diabetic macular oedema.

FUNDING

F Hoffmann-La Roche.

TENAYA and LUCERNE

Purpose

To describe the design and rationale of the phase 3 TENAYA (ClinicalTrials.gov identifier, NCT03823287) and LUCERNE (ClinicalTrials.gov identifier, NCT03823300) trials that aimed to assess efficacy, safety, and durability of faricimab, the first bispecific antibody for intraocular use, which independently binds and neutralizes both angiopoietin-2 and vascular endothelial growth factor-A (VEGF-A) versus aflibercept in patients with neovascular age-related macular degeneration (nAMD).

Design

Identical, global, double-masked, randomized, controlled, phase 3 clinical trials.

Participants

Adults with treatment-naïve nAMD.

Methods

These trials were designed to evaluate patients randomized to receive faricimab 6.0 mg up to every 16 weeks after 4 initial every-4-week doses or aflibercept 2.0 mg every 8 weeks after 3 initial every-4-week doses. The initial doses in the faricimab arm were followed by individualized fixed treatment intervals up to week 60, based on disease activity assessment at weeks 20 and 24, guided by central subfield thickness, best-corrected visual acuity (BCVA), and investigator assessment. The primary efficacy end point was BCVA change from baseline averaged over weeks 40, 44, and 48. Secondary end points included the proportion of patients receiving every-8-week, every-12-week, and every-16-week faricimab and anatomic outcomes. Safety outcomes included incidence and severity of ocular and nonocular adverse events. From week 60, faricimab-treated patients followed a personalized treatment interval (PTI), a novel protocol-driven treat-and-extend regimen with interval adjustment from every 8 weeks to every 16 weeks based on individualized treatment response measured by anatomic criteria, functional criteria, and investigator assessment of patients’ disease activity.

Main Outcome Measures

Rationale for trial design and PTI approach.

Results

The TENAYA and LUCERNE trials were the first registrational trials in nAMD to test fixed dosing regimens up to every 16 weeks based on patients' disease activity in year 1 and incorporate a PTI paradigm during year 2. The PTI approach was designed to tailor treatment intervals to individual patient needs, to reflect clinical practice treatment practice, and to reduce treatment burden.

Conclusions

The innovative trial design rationale for the TENAYA and LUCERNE trials included maximizing the benefits of angiopoietin-2 blockade through dosing up to every 16 weeks and PTI regimens based on patients' disease activity while fulfilling health authority requirements for potential registrational efforts.

Feasibility Study of a Multimodal, Cloud-Based, Diabetic Retinal Screening Program in a Workplace Environment

Purpose

To evaluate the feasibility of capturing and interpreting retinal images in a workplace environment using a multimodal, cloud-based, diabetic retinal screening program combined with electronic self-reported questionnaires. The burden of diabetic retinopathy (DR) and other retinal conditions, healthcare utilization, and visual function were also assessed.

Methods

A cross-sectional feasibility study was conducted at the Genentech, Inc., Campus Health Center. Eyes of participants were imaged using ultra-widefield (UWF) color fundus photography (CFP) and spectral-domain optical coherence tomography (SD-OCT). A cloud-based platform was used for the automated, seamless transfer of images to a remote reading center for evaluation for DR and other retinal pathologies. Electronic surveys collected participants’ self-reported medical histories, healthcare utilization, and visual function data.

Results

Among 100 participants (mean age, 43.9 years; 44% male), 33% of them self-reported diabetes. Eye examinations within the past 12 months were reported by 71% of all participants (n = 71/100) and by 85% (n = 28/33) of those with self-reported diabetes. Among participants with complete screening images from both UWF-CFP and SD-OCT, 20% (n = 6/30) of those with self-reported diabetes and 8.5% (n = 5/59) of participants with no history of diabetes were unaware they had mild/moderate nonproliferative DR. Among all participants, 20% (20/100) had a retinal finding, on either UWF-CFP or SD-OCT, or both, which prompted a referral for further evaluation.

Conclusions

A retinal screening program deployed via a secure, scalable, and interoperable cloud-based platform was feasible and conveniently integrated into the workplace.

Translational Relevance

Cloud-based platforms could be used to promote a secure, scalable, and interoperable system for retinal screening in nontraditional environments.

Development of Deep Learning Models to Predict Best-Corrected Visual Acuity from Optical Coherence Tomography

Purpose

To develop deep learning (DL) models to predict best-corrected visual acuity (BCVA) from optical coherence tomography (OCT) images from patients with neovascular age-related macular degeneration (nAMD).

Methods

Retrospective analysis of OCT images and associated BCVA measurements from the phase 3 HARBOR trial (NCT00891735). DL regression models were developed to predict BCVA at the concurrent visit and 12 months from baseline using OCT images. Binary classification models were developed to predict BCVA of Snellen equivalent of <20/40, <20/60, and ≤20/200 at the concurrent visit and 12 months from baseline.

Results

The regression model to predict BCVA at the concurrent visit had R² = 0.67 (root-mean-square error [RMSE] = 8.60) in study eyes and R² = 0.84 (RMSE = 9.01) in fellow eyes. The best classification model to predict BCVA at the concurrent visit had an area under the receiver operating characteristic curve (AUC) of 0.92 in study eyes and 0.98 in fellow eyes. The regression model to predict BCVA at month 12 using baseline OCT had R² = 0.33 (RMSE = 14.16) in study eyes and R² = 0.75 (RMSE = 11.27) in fellow eyes. The best classification model to predict BCVA at month 12 had AUC = 0.84 in study eyes and AUC = 0.96 in fellow eyes.

Conclusions

DL shows promise in predicting BCVA from OCTs in nAMD. Further research should elucidate the utility of models in clinical settings.

Translational Relevance

DL models predicting BCVA could be used to enhance understanding of structure–function relationships and develop more efficient clinical trials.

Progression from Early/Intermediate to Advanced Forms of Age-Related Macular Degeneration in a Large UK Cohort: Rates and Risk Factors

PURPOSE

To estimate rates and risk factors for progression to geographic atrophy (GA) or choroidal neovascularization (CNV) among eyes diagnosed with early or intermediate age-related macular degeneration (AMD) in clinical practice.

DESIGN

Retrospective cohort analysis of a multicenter electronic medical record (EMR) database from the United Kingdom.

PARTICIPANTS

Patients aged 50 years or more with diagnosis of early/intermediate AMD in at least 1 eye (the study eye) and no evidence of CNV or GA in the study eye, from 10 clinical sites using the EMR.

METHODS

Anonymized data for 40 543 patients with a diagnosis of early/intermediate AMD were extracted between October 2000 and February 2016 from EMR database records held in the 10 sites. A sample of records randomly selected from each center was used to validate disease definitions. Records were analyzed by subgroup, based on the AMD status of the fellow eye. Multivariate Cox regression models identified other predictors of disease progression.

MAIN OUTCOME MEASURES

Progression rate (per 100 person-years) to GA or CNV in study eyes with early/intermediate AMD by fellow eye status and identified risk factors for progression.

RESULTS

Study eyes with early/intermediate AMD and a diagnosis of CNV in the fellow eye progressed to CNV fastest (at a rate of 15.2 per 100 person-years), and those with a diagnosis of GA in the fellow eye progressed to GA fastest (11.2 per 100 person-years), compared with the rates per 100 person-years of progression to CNV (3.2-11.9) or GA (2.0-7.8) in the other subgroups. In individuals with bilateral early/intermediate AMD, rates of progression to GA or CNV were 2.0 and 3.2 per 100 person-years, respectively. In the multivariate model, age, female sex, and cardiovascular disease were associated with an increased risk for progression to advanced AMD, whereas diabetes and glaucoma were associated with a decreased rate of progression (hazard ratios, 0.45 and 0.64, respectively).

CONCLUSIONS

Progression to GA or CNV was observed frequently in eyes with early/intermediate AMD, with the status of the fellow eye affecting the rate of progression. Novel associations with risk factors were observed and require replication in other cohorts.

Post-exercise hypotension and skeletal muscle oxygenation is regulated by nitrate-reducing activity of oral bacteria

Post-exercise hypotension (PEH) is a common physiological phenomenon leading to lower blood pressure after acute exercise, but it is not fully understood how this intriguing response occurs. This study investigated whether the nitrate-reducing activity of oral bacteria is a key mechanism to trigger PEH. Following a randomized, double blind and crossover design, twenty-three healthy individuals (15 males/8 females) completed two treadmill trials at moderate intensity. After exercise, participants rinsed their mouth with antibacterial mouthwash to inhibit the activity of oral bacteria or a placebo mouthwash. Blood pressure was measured before, 1h and 2 h after exercise. The microvascular response to a reactive hyperaemia test, as well as blood and salivary samples were taken before and 2 h after exercise to analyse nitrate and nitrite concentrations and the oral microbiome. As expected, systolic blood pressure (SBP) was lower (1 h: -5.2 ± 1.0 mmHg; P < 0.001); 2 h: -3.8 ± 1.1 mmHg, P = 0.005) after exercise compared to baseline in the placebo condition. This was accompanied by an increase of circulatory nitrite 2 h after exercise (2h: 100 ± 13 nM) compared to baseline (59 ± 9 nM; P = 0.013). Additionally, an increase in the peak of the tissue oxygenation index (TOI) during the reactive hyperaemia response was observed after exercise (86.1 ± 0.6%) compared to baseline levels (84.8 ± 0.5%; P = 0.010) in the placebo condition. On the other hand, the SBP-lowering effect of exercise was attenuated by 61% at 1 h in the recovery period, and it was fully attenuated 2 h after exercise with antibacterial mouthwash. This was associated with a lack of changes in circulatory nitrite (P > 0.05), and impaired microvascular response (peak TOI baseline: 85.1 ± 3.1%; peak TOI post-exercise: 84.6 ± 3.2%; P > 0.05). Diversity of oral bacteria did not change after exercise in any treatment. These findings show that nitrite synthesis by oral commensal bacteria is a key mechanism to induce the vascular response to exercise over the first period of recovery thereby promoting lower blood pressure and greater muscle oxygenation.

From statics of composites to acoustic metamaterials

The Hashin-Shtrikman formalism for the static response of a composite is first summarized, in a form applicable to anisotropic media and arbitrary two-point correlations. Its extension to dynamic response is then explained and in particular the extra coupling, for stress with velocity as well as strain, and momentum density with strain as well as velocity that inevitably follows, is highlighted. The more recent dynamical formulations which incorporate extra flexibility through the use of a weighted mean displacement also receive mention. The article is concluded with an explicit analysis of a simple model random composite and some lessons are drawn from the solution, which exposes at least one clear gap in existing knowledge and requires further research. This article is part of the theme issue 'Modelling of dynamic phenomena and localization in structured media (part 1)'.

Deep Learning Predicts OCT Measures of Diabetic Macular Thickening From Color Fundus Photographs

Purpose

To develop deep learning (DL) models for the automatic detection of optical coherence tomography (OCT) measures of diabetic macular thickening (MT) from color fundus photographs (CFPs).

Methods

Retrospective analysis on 17,997 CFPs and their associated OCT measurements from the phase 3 RIDE/RISE diabetic macular edema (DME) studies. DL with transfer-learning cascade was applied on CFPs to predict time-domain OCT (TD-OCT)-equivalent measures of MT, including central subfield thickness (CST) and central foveal thickness (CFT). MT was defined by using two OCT cutoff points: 250 μm and 400 μm. A DL regression model was developed to directly quantify the actual CFT and CST from CFPs.

Results

The best DL model was able to predict CST ≥ 250 μm and CFT ≥ 250 μm with an area under the curve (AUC) of 0.97 (95% confidence interval [CI], 0.89-1.00) and 0.91 (95% CI, 0.76-0.99), respectively. To predict CST ≥ 400 μm and CFT ≥ 400 μm, the best DL model had an AUC of 0.94 (95% CI, 0.82-1.00) and 0.96 (95% CI, 0.88-1.00), respectively. The best deep convolutional neural network regression model to quantify CST and CFT had an R2 of 0.74 (95% CI, 0.49-0.91) and 0.54 (95% CI, 0.20-0.87), respectively. The performance of the DL models declined when the CFPs were of poor quality or contained laser scars.

Conclusions

DL is capable of predicting key quantitative TD-OCT measurements related to MT from CFPs. The DL models presented here could enhance the efficiency of DME diagnosis in tele-ophthalmology programs, promoting better visual outcomes. Future research is needed to validate DL algorithms for MT in the real-world.

Vision-Related Functional Burden of Diabetic Retinopathy Across Severity Levels in the United States

Importance

Among adults with diabetes in the United States, severe forms of diabetic retinopathy (DR) are significantly associated with a greater vision-related functional burden.

Objective

To assess the functional burden of DR across severity levels in the United States.

Design, Setting, and Participants

This cross-sectional study was based on 1004 participants 40 years or older with diabetes and valid ocular and sociodemographic outcomes in the National Health and Nutrition Examination Surveys (NHANES) (2005-2006 and 2007-2008). Diabetic retinopathy was based on fundus photograph grading, using the Early Treatment Diabetic Retinopathy Study severity scale. The analysis was performed from October 15, 2016, to June 15, 2017.

Main Outcomes and Measures

Functional difficulties secondary to vision were assessed during a household questionnaire in which participants self-reported difficulty with reading, visuospatial tasks (ie, close-up work or finding things on a crowded shelf), mobility (ie, walking down steps, stairs, or curbs), and driving. The main outcome measure was vision-related functional burden, which was defined as present for individuals reporting moderate or greater difficulty in any of the aforementioned tasks.

Results

Of the 1004 persons with diabetes analyzed for this study (mean age, 65.7 years [95% CI, 64.0-67.3 years]; 51.1% male [95% CI, 47.1-55.2] and 48.9% female [95% CI, 44.8-52.9]), the prevalence was 72.3% for no retinopathy, 25.4% for mild and moderate nonproliferative diabetic retinopathy (NPDR), and 2.3% for severe NPDR or proliferative diabetic retinopathy (PDR). The prevalence of vision-related functional burden was 20.2% (95% CI, 16.3%-24.1%) for those with no retinopathy, 20.4% (95% CI, 15.3%-27.8%) for those with mild and moderate NPDR, and 48.5% (95% CI, 25.6%-71.5%) for those with severe NPDR or PDR (P = .02). In multivariable analysis, the odds of vision-related functional burden were significantly greater among those with severe NPDR or PDR relative to those with no retinopathy (adjusted odds ratio [aOR], 3.59; 95% CI, 1.29-10.05; P = .02). Those with severe NPDR or PDR did not have a statistically significant greater odds of vision-related functional burden than did those with mild or moderate NPDR (aOR, 2.70; 95% CI, 0.93-7.78; P = .07).

Conclusions and Relevance

Among US adults with diabetes, approximately half of those with severe NPDR or PDR had difficulty with at least one visual function task. Moreover, vision-related functional burden was significantly greater among those with severe NPDR or PDR than among those with no retinopathy. These data suggest the importance of preventing severe forms of DR to mitigate the vision-related functional burden among US adults with diabetes. Future studies should complement our study by assessing the association of worsening retinopathy with objectively measured functional outcomes.

The Prevalence of Myopic Choroidal Neovascularization in the United States: Analysis of the IRIS(®) Data Registry and NHANES

PURPOSE

To determine the prevalence of high myopia (HM), progressive high (degenerative) myopia (PHM), and myopic choroidal neovascularization (mCNV) in the United States.

DESIGN

Cross-sectional study.

PARTICIPANTS

Individuals aged 18 years and older participating in the National Health and Nutrition Examination Survey (NHANES) and patients aged 18 years and older seen in clinics participating in the American Academy of Ophthalmology's Intelligent Research in Sight (IRIS(®)) Registry.

METHODS

We analyzed NHANES data from 2005 to 2008 to determine the prevalence of HM in the United States. This prevalence was then applied to estimates from the US Population Census (2014) to arrive at a population burden of HM at the diopter level in the United States. Data from the IRIS Registry were used to calculate the real-world prevalence rates of PHM and mCNV among patients with HM at the diopter level. This was subsequently applied to this reference population with HM to calculate the diopter-adjusted prevalence and population burden of PHM and mCNV in the United States in 2014.

MAIN OUTCOME MEASURES

High myopia was defined as myopic refractive error of ≤6.0 diopters in the right eye. Progressive HM was defined as HM with the International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) code of "360.21: Progressive High (Degenerative) Myopia." Myopic CNV was defined as HM with the presence of subretinal/choroidal neovascularization indicated by the ICD-9-CM diagnosis of "362.16: Retinal Neovascularization NOS."

RESULTS

The estimated diopter-adjusted prevalence of HM, PHM, and mCNV was 3.92% (95% confidence interval [CI], 2.82-5.60), 0.33% (95% CI, 0.21-0.55), and 0.017% (95% CI, 0.010-0.030), respectively, among adults in the United States aged 18 years and older in 2014. This translated into a population burden of approximately 9 614 719 adults with HM, 817 829 adults with PHM, and 41 111 adults with mCNV in the United States in 2014.

CONCLUSIONS

Although HM and PHM impose a relatively large burden among adults in the United States, mCNV seems to be a rare disease. Relating data from the IRIS Registry and NHANES could be a novel method for assessing ophthalmic disease prevalence in the United States. Future studies should aim to better assess current treatment patterns and optimal management strategies of this condition.

Visual impairment, uncorrected refractive error, and objectively measured balance in the United States

IMPORTANCE

Further research is crucial to better understand the reason for falls in individuals with visual impairment (VI) and to develop appropriate fall prevention strategies.

OBJECTIVE

To compare balance measures in individuals with normal vision, VI, and uncorrected refractive error (URE).

DESIGN AND SETTING

Cross-sectional study based on a national survey sample.

PARTICIPANTS

A total of 4590 adults, 40 years or older, participating in the 2001 through 2004 National Health and Nutrition Examination Survey.

MAIN OUTCOME MEASURES

Participants completed tests of standing balance with eyes open or eyes closed on a firm or compliant (foam) surface. Eyes-closed testing on a foam surface primarily assessed vestibular balance by minimizing visual and proprioceptive inputs. The main outcome measure was time to balance failure on firm and foam surface testing. Participants also self-reported difficulty with falling during the last year.

RESULTS

Failure during eyes-open balance testing conditions or eyes-closed balance testing on a firm surface was not more common among participants with VI-associated or URE-associated vision loss (P > .22). In eyes-closed foam surface balance testing, multivariable models demonstrated higher rates of balance loss with VI-associated vision loss (P = .02) and with URE-associated vision loss (P = .04) (hazard ratio, 1.7 per logarithm of the minimum angle of resolution [logMAR] unit change [10 lines] for both). Self-reported falling difficulty was associated with worse VI (odds ratio, 3.7 per logMAR unit change; P = .03) but not with worse URE (odds ratio, 3.4 per logMAR unit change; P = .14).

CONCLUSIONS AND RELEVANCE

The vestibular contribution to balance (measured with eyes closed on a foam surface) was worse for individuals with VI or URE. Reduced visual inputs may weaken the vestibulo-ocular reflex, an important system that maintains the effectiveness of vestibular balance. Alternately, common degenerative pathways or lower physical activity levels may affect balance, particularly among those with VI.

Impact of community-based behaviour-change management on perceived neonatal morbidity: a cluster-randomized controlled trial in Shivgarh, Uttar Pradesh, India

In the context of high neonatal mortality rate (NMR) in developing country settings, a promising strategy for enhancing newborn health is promotion of preventive newborn care practices. We measured the effect of a behaviour-change intervention on perceived neonatal illnesses in rural Uttar Pradesh, India. The study was nested in a cluster-randomized controlled trial of the impact of a package of essential newborn care on NMR. We prospectively enrolled 802 mothers and administered a questionnaire on perceived neonatal morbidities. Regression analysis showed that newborns in the intervention clusters had significantly lower risk of perceived diarrhoea [adjusted relative risk (aRR) 0.67, 95% confidence interval (CI) 0.49-0.90] and skin-related complications [aRR 0.67, 95% CI 0.45-1.00] compared to newborns in the comparison area. Assuming incidence of perceived illnesses is a proxy for actual morbidity rates, we conclude that promotion of preventive care practices through behaviour-change interventions was effective in reducing neonatal morbidities.

Gender differences in perception and care-seeking for illness of newborns in rural Uttar Pradesh, India

Although gender-based health disparities are prevalent in India, very little data are available on care-seeking patterns for newborns. In total, 255 mothers were prospectively interviewed about their perceptions and action surrounding the health of their newborns in rural Uttar Pradesh, India. Perception of illness was significantly lower in incidence (adjusted odds ratio=0.56, 95% confidence interval 0.33-0.94) among households with female versus male newborns. While the overall use of healthcare providers was similar across gender, the average expenditure for healthcare during the neonatal period was nearly four-fold higher in households with males (Rs 243.3 +/- 537.2) compared to females (Rs 65.7 +/- 100.7) (p=0.07). Households with female newborns used cheaper public care providers whereas those with males preferred to use private unqualified providers perceived to deliver more satisfactory care. These results suggest that, during the neonatal period, care-seeking for girls is neglected compared to boys, laying a foundation for programmes and further research to address gender differences in neonatal health in India.

Repeated low-level formaldehyde exposure produces cross-sensitization to cocaine: possible relevance to chemical sensitivity in humans

Sensitivity to chemicals in humans has been proposed to be an acquired disorder in which individuals become increasingly sensitive to chemicals in the environment. A possible link between the manifestation of psychiatric symptoms in individuals claiming sensitivity to chemicals was investigated based on a leading hypothesis put forth by Bell and co-workers (1992) to explain the amplification of symptoms after chemical exposure. The hypothesis is that chemical sensitivities may be akin to sensitization observed in rodents after repeated psychostimulants. Repeated exposure to psychostimulants enhances behavioral activity and the underlying neurochemical responses in specific limbic pathways; a similar sensitization of limbic pathways has been proposed to occur in individuals who become sensitive to chemicals. To test this hypothesis, female Sprague-Dawley rats were exposed to either air or formaldehyde (Form) for 1 h/day for 7 days or 20 days (5 days/week x 4 weeks). Two to 4 days after the last exposure, rats were given a cocaine challenge (= early withdrawal) followed by an additional cocaine challenge 4-6 weeks later (= late withdrawal). No differences in cocaine-induced locomotor activity were noted between groups after 7 days of exposure. However, after 20 days of exposure to Form, vertical activity was significantly elevated at both early and late withdrawal times. These studies demonstrate that behavioral sensitization occurs after long-term, but not short-term, low-level exposure to Form, and lends support to the limbic system sensitization hypothesis of sensitivity to chemicals in humans.

Enteroscopy-enteroclysis: experience with a combined endoscopic-radiographic technique

BACKGROUND

Video enteroscopy provides high-quality diagnostic and therapeutic capabilities in the proximal small bowel. Enteroclysis remains an essential diagnostic technique in the distal small bowel. We report our experience with the combination of these techniques.

METHODS

Seventy-one patients with obscure gastrointestinal bleeding (group A, 54 patients) or abnormal radiologic studies (group B, 17 patients) were evaluated with enteroscopy. Enteroclysis via a tube inserted on withdrawal of the enteroscope was performed in all patients with nondiagnostic enteroscopy.

RESULTS

Enteroscopy identified bleeding sites in 29 of 54 (54%) group A patients (12 angiodysplasia, 10 ulcers, 7 gastric erosions, 1 vessel, 1 aortoenteric fistula), and lesions in 11 of 17 (65%) group B patients (7 ulcers, 3 benign strictures, 2 radiation enteritis, 1 mass). In group A, 13 (24%) patients had findings detectable by standard esophagogastroduodenoscopy. Enteroclysis identified masses in 2 of 24 (8%) group A patients, and lesions in 5 of 10 (50%) group B patients (3 strictures, 1 mass, 1 large diverticulum). No complications occurred.

CONCLUSIONS

The combination of enteroscopy and enteroclysis is safe and offers quality small bowel examinations in more comfortable and convenient single diagnostic sittings. This combination detected bleeding sources in 57% and lesions in 70% of patients. Though enteroclysis identified bleeding sources in only 8% of patients, this study excluded lesions other than angiodysplasia.

Enteroscopy with enteroclysis

The authors conclude that their experiences support the conclusion that the combination of enteroscopy and enterocysis is safe and offers quality small bowel examinations in a more comfortable and convenient single diagnostic setting. Although enteroclysis has identified bleeding sources in only 8% of patients who underwent this study, other lesions than angiodysplasia were confidently excluded in the remainder of patients. The combined procedure is well tolerated in the outpatient setting, more comfortable, and safer by decreasing radiation exposures than enteroclysis alone. Use of small bowel enteroscopy at an earlier stage in the evaluation of patients with obscure gastrointestinal bleeding increases cost effectiveness without compromising quality.

Proposed animal neurosensitization model for multiple chemical sensitivity in studies with formalin

A potentially promising line of animal research relevant to multiple chemical sensitivity (MCS) is that of sensitization in the central nervous system (CNS), particularly limbic pathways in the brain. Sensitization is the progressive and enduring enhancement in behavioral and neurochemical responses that occurs after repeated exposure to psychostimulants or environmental stressors. Since the onset and progression of sensitization has many parallels with that of MCS, it has been proposed that MCS may be initiated through a mechanism similar to the sensitization of CNS components occurring in the rodent. To test this hypothesis, female Sprague-Dawley rats were exposed to formalin vapors (FORM, 11 ppm) or water vapor (control) 1 h/day for 7 days. The next day, a saline injection was given followed by a cocaine injection (15 mg/kg, i.p.) 24 h later, and locomotor activity was monitored. Animals pretreated with repeated FORM inhalation demonstrated a significantly enhanced locomotor response to cocaine compared to controls, an indicator that specific limbic pathways may have been sensitized. At 4 weeks of withdrawal from FORM exposure, a subset of animals remained sensitized to a cocaine challenge. No differences were found between groups after a saline injection. In a second experiment, animals were screened prior to FORM or water exposure for their response to a novel situation, a measure believed to reflect an animal's general responsiveness to stimuli. Rats were divided into high responders (HR) or low responders (LR), based on their locomotion in a novel cage. Results from three behavioral tests demonstrated that HR and LR were differentially affected by exposure to FORM. In a passive avoidance test, HR and LR appeared to be different in their distribution of responses, while HR and LR responses in the FORM group were nearly identical. On the elevated plus maze test of anxiety, HR spent more time on the open arms than LR in both treatment groups, with significant differences between HR and LR in the FORM, but not water, treated group. On a hot plate test to measure nociceptive levels, no differences occurred between HR and LR in the control group, whereas nociception of LR tended toward an increase compared to HR in the FORM-exposed group. Results from the second experiment suggest that the effects of FORM exposure may be obscured by examining behavior in a heterogeneous population (HR and LR). This approach using animal models may help define neural substrates that mediate the amplification of responses of a subpopulation of individuals to chemicals in the environment.