METformin for the MINimization of Geographic Atrophy Progression (METforMIN): A Randomized Trial

Purpose

Metformin use has been associated with a decreased risk of age-related macular degeneration (AMD) progression in observational studies. We aimed to evaluate the efficacy of oral metformin for slowing geographic atrophy (GA) progression.

Design

Parallel-group, multicenter, randomized phase II clinical trial.

Participants

Participants aged ≥ 55 years without diabetes who had GA from atrophic AMD in ≥ 1 eye.

Methods

We enrolled participants across 12 clinical centers and randomized participants in a 1:1 ratio to receive oral metformin (2000 mg daily) or observation for 18 months. Fundus autofluorescence imaging was obtained at baseline and every 6 months.

Main Outcome Measures

The primary efficacy endpoint was the annualized enlargement rate of the square root-transformed GA area. Secondary endpoints included best-corrected visual acuity (BCVA) and low luminance visual acuity (LLVA) at each visit.

Results

Of 66 enrolled participants, 34 (57 eyes) were randomized to the observation group and 32 (53 eyes) were randomized to the treatment group. The median follow-up duration was 13.9 and 12.6 months in the observation and metformin groups, respectively. The mean ± standard error annualized enlargement rate of square root transformed GA area was 0.35 ± 0.04 mm/year in the observation group and 0.42 ± 0.04 mm/year in the treatment group (risk difference = 0.07 mm/year, 95% confidence interval = -0.05 to 0.18 mm/year; P = 0.26). The mean ± standard error decline in BCVA was 4.8 ± 1.7 letters/year in the observation group and 3.4 ± 1.1 letters/year in the treatment group (P = 0.56). The mean ± standard error decline in LLVA was 7.3 ± 2.5 letters/year in the observation group and 0.8 ± 2.2 letters/year in the treatment group (P = 0.06). Fourteen participants in the metformin group experienced nonserious adverse events related to metformin, with gastrointestinal side effects as the most common. No serious adverse events were attributed to metformin.

Conclusions

The results of this trial as conducted do not support oral metformin having effects on reducing the progression of GA. Additional placebo-controlled trials are needed to explore the role of metformin for AMD, especially for earlier stages of the disease.

Financial Disclosures

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

Bilaterally subluxed diffractive intraocular lenses: big expectations and even bigger comorbidities

A 78-year-old woman with an ocular history of cataract surgery with a diffractive intraocular lens (IOL) in each eye has developed fluctuating vision, greater in the right eye than the left eye, after 4 years. She has a history of inactive central serous retinopathy and a vision potential of 20/25 + 2 in the right eye and 20/25 in the left eye. She has well-controlled diabetes, hypertension, and hypercholesterolemia. She has enjoyed her spectacle independence for some time and wishes to have her vision restored. On examination, her uncorrected distance visual acuity (UDVA) was 20/50 in the right eye and 20/25 in the left eye and her uncorrected near visual acuity (UNVA) was J3 in the right eye and J1 in the left eye. Intraocular pressures (IOPs) measured 22 mm Hg in the right eye and 18 mm Hg in the left eye. Pupils had limited reactivity with irregularity in the right eye but no obvious relative afferent pupillary defect. Motility and confrontation visual fields were unremarkable in both eyes. Retinal acuity meter was 20/20 in both eyes, and manifest refraction was plano -1.25 × 105 20/40, J3 in the right eye and +0.50 × 20/25, J1 in the left eye. Pertinent findings on slitlamp examination included temporal iris atrophy and transillumination defects greater in the right eye than the left eye, peripupillary pseudoexfoliative changes in both eyes, significant inferior subluxation of a diffractive 3-piece posterior chamber IOL in the capsular bag with lens-pitting peripherally and few central, moderate pseudophacodonesis, and an open posterior capsule in the right eye. In the left eye, she had mild inferior subluxation of a single-piece acrylic diffractive IOL in the capsular bag with moderate pseudophacodonesis and an open posterior capsule (Figure 1JOURNAL/jcrs/04.03/02158034-202403000-00019/figure1/v/2024-02-20T193212Z/r/image-tiff). All other anterior segment findings were unremarkable. On dilated posterior examination, she had a cup-to-disc ratio of 0.50 in the right eye and 0.65 in the left eye without edema hemorrhage or pallor. There were attenuated vessels in both eyes, posterior vitreous detachment in both eyes, and a few small drusen peripherally in both eyes. There was retinal pigment epithelium irregularity and dropout parafoveal in the right eye and subfoveal in the left eye (Figure 2). There was no evidence of macular edema, subretinal fluid, choroidal thickening, or neovascular membranes. The periphery was unremarkable in both eyes.JOURNAL/jcrs/04.03/02158034-202403000-00019/figure2/v/2024-02-20T193212Z/r/image-tiff What testing would you obtain preoperatively to help guide your decision-making? How would you counsel the patient regarding comorbid conditions and expectations?

Microvascular disease not type 2 diabetes is associated with increased cortical porosity: A study of cortical bone microstructure and intracortical vessel characteristics

Introduction

Fracture risk is elevated in type 2 diabetes (T2D) despite normal or even high bone mineral density (BMD). Microvascular disease (MVD) is a diabetic complication, but also associated with other diseases, for example chronic kidney disease. We hypothesize that increased fracture risk in T2D could be due to increased cortical porosity (Ct.Po) driven by expansion of the vascular network in MVD. The purpose of this study was to investigate associations of T2D and MVD with cortical microstructure and intracortical vessel parameters.

Methods

The study group consisted of 75 participants (38 with T2D and 37 without T2D). High-resolution peripheral quantitative CT (HR-pQCT) and dynamic contrast-enhanced MRI (DCE-MRI) of the ultra-distal tibia were performed to assess cortical bone and intracortical vessels (outcomes). MVD was defined as ≥1 manifestation including neuropathy, nephropathy, or retinopathy based on clinical exams in all participants. Adjusted means of outcomes were compared between groups with/without T2D or between participants with/without MVD in both groups using linear regression models adjusting for age, sex, BMI, and T2D as applicable.

Results

MVD was found in 21 (55 %) participants with T2D and in 9 (24 %) participants without T2D. In T2D, cortical pore diameter (Ct.Po.Dm) and diameter distribution (Ct.Po.Dm.SD) were significantly higher by 14.6 μm (3.6 %, 95 % confidence interval [CI]: 2.70, 26.5 μm, p = 0.017) and by 8.73 μm (4.8 %, CI: 0.79, 16.7 μm, p = 0.032), respectively. In MVD, but not in T2D, cortical porosity was significantly higher by 2.25 % (relative increase = 12.9 %, CI: 0.53, 3.97 %, p = 0.011) and cortical BMD (Ct.BMD) was significantly lower by -43.6 mg/cm3 (2.6 %, CI: -77.4, -9.81 mg/cm3, p = 0.012). In T2D, vessel volume and vessel diameter were significantly higher by 0.02 mm3 (13.3 %, CI: 0.004, 0.04 mm3, p = 0.017) and 15.4 μm (2.9 %, CI: 0.42, 30.4 μm, p = 0.044), respectively. In MVD, vessel density was significantly higher by 0.11 mm-3 (17.8 %, CI: 0.01, 0.21 mm-3, p = 0.033) and vessel volume and diameter were significantly lower by -0.02 mm3 (13.7 %, CI: -0.04, -0.004 mm3, p = 0.015) and - 14.6 μm (2.8 %, CI: -29.1, -0.11 μm, p = 0.048), respectively.

Conclusions

The presence of MVD, rather than T2D, was associated with increased cortical porosity. Increased porosity in MVD was coupled with a larger number of smaller vessels, which could indicate upregulation of neovascularization triggered by ischemia. It is unclear why higher variability and average diameters of pores in T2D were accompanied by larger vessels.

Feasibility demonstration of a device for vitreous liquid biopsy incidental to intravitreal injection

PURPOSE

VitreoDx is an experimental device enabling push-button collection of a neat vitreous liquid biopsy incidental to an intravitreal injection. We explored the ability of the device to collect a sample usable for proteomic biomarker discovery and testing.

DESIGN

Pilot study using ex vivo human eyes.

METHODS

Non-vitrectomized, human eyes from nine donors 75-91 years of age were refrigerated in BSS and used within 5 days of death. Four VitreoDx devices fitted with 25G needles, and four staked needle insulin syringes with 30G needles, were inserted at equal intervals through the pars plana of each eye and held in place by a fixture. The sampling mode of each VitreoDx device was triggered to attempt to acquire a liquid biopsy up to 70 μL. The plunger of each insulin syringe was retracted to attempt to obtain a liquid biopsy with a maximum volume of 50 μL. Samples acquired with the VitreoDx were extracted to polypropylene cryovials, refrigerated to -80 ºC, and sent for offsite proteomic analysis by proximity extension assay with a focus on panels containing approved and pipelined drug targets for neovascular disease and inflammatory factors.

RESULTS

Of the attempted liquid biopsies with the novel 25G VitreoDx, 92% (66 of 72) resulted in successful acquisition (>25 μL) while 89% (64 of 72) attempted by a traditional 30G needle resulted in a successful acquisition. Sample volume sufficient for proteomics array analysis was acquired by the VitreoDx for every eye. Detectable protein was found for 151 of 166 unique proteins assayed in at least 25% of eyes sampled by VitreoDx.

CONCLUSIONS

The high acquisition rate achieved by the prototype was similar to that achieved in previous clinical studies where a standard syringe was used with a 25G needle to biopsy vitreous fluid directly prior to standard intravitreal injection. Successful aspiration rates were likewise high for 30G needles. Together, these suggest that it is possible to routinely acquire liquid vitreous biopsies from patients who typically receive intravitreal injections with an injection device using a standard size needle without a vitreous cutter. Protein analysis shows that proteins of interest survive the sampling mechanism and may have potential to direct care in the future.

Vitreous Biomarkers for Proliferative Vitreoretinopathy Prognostication in Patients Undergoing Primary Retinal Detachment Repair

Purpose

To compare baseline levels of exploratory biomarkers in the vitreous fluid of patients with primary retinal detachment who subsequently develop proliferative vitreoretinopathy (PVR) versus those who do not.

Methods

In this exploratory case-control study, we evaluated the baseline protein biomarker levels from a biobank containing the vitreous fluid of patients who had undergone primary pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment. Undiluted samples were collected at the time of PPV and stored at -80°C. Samples from 13 patients who developed PVR within 6 months (PVR group) and 13 age- and gender-matched controls who did not develop PVR (control group) were included. Protein abundance levels were evaluated using a proximity extension assay, and a confirmatory enzyme-linked immunosorbent assay (ELISA) was used to measure the concentration of vimentin.

Results

Baseline vimentin (Normalized Protein eXpression [NPX], 8.6 vs. 6.4, P < 0.0001) and heme oxygenase 1 (NPX 8.9 vs. 7.0, P < 0.001) levels were found to be elevated in vitreous fluid of patients who subsequently developed PVR compared to those who did not. Confirmatory analysis using ELISA demonstrated mean vimentin concentrations of 7254 vs. 2727 ng/mL in the PVR versus control groups (P = 0.0152). The odds ratio for developing PVR was 14 (confidence interval, 1.4-168; P = 0.03), assuming a baseline vimentin threshold of 7500 ng/mL.

Conclusions

Vimentin is an intermediate filament protein expressed by retinal glial cells, and our data combined with prior evidence suggest that it may serve as an early vitreous biomarker for subsequent PVR formation and reactive gliosis. Furthermore, we found, for the first time, elevated baseline levels of heme oxygenase 1, a measurable indicator of oxidative stress.

Translational Relevance

Our positive findings could impact clinical care for retinal detachment patients by facilitating risk stratification for targeted interventions or closer monitoring in those at the highest risk of developing PVR.

Individual and Systems-Based Risk Factors for Diabetic Vitrectomy in an Urban Safety-Net Hospital

OBJECTIVE

To identify individual and systems-focused risk factors for pars plana vitrectomy among patients with proliferative diabetic retinopathy (PDR) in a diverse, urban, safety-net hospital setting.

DESIGN

Single-center, retrospective, observational, case-control study at Zuckerberg San Francisco General Hospital and Trauma Center between 2017 and 2022.

SUBJECTS

Two hundred twenty-two patients with PDR over a 5-year span (2017-2022), consisting of 111 cases who underwent vitrectomy for vision-threatening complications (tractional retinal detachment, nonclearing vitreous hemorrhage, and neovascular glaucoma) and 111 controls with PDR with no history of vitrectomy or vision-threatening complications. Controls were matched 1:1 through incidence density sampling.

METHODS

Medical records were reviewed from time of entry into hospital system to vitrectomy date (or date-matched clinic visit for controls). Individual-focused exposures included age, gender, ethnicity, language, homelessness, incarceration, smoking status, area deprivation index, insurance status, baseline retinopathy stage, baseline visual acuity, baseline hemoglobin A1c, panretinal photocoagulation status, and cumulative anti-VEGF treatments. System-focused exposures included external department involvement, referral route, time within hospital and ophthalmology systems, interval between screening and ophthalmology appointment, interval between conversion to proliferative disease and panretinal photocoagulation or first treatment, and loss-to-follow-up in intervals of active proliferative disease.

MAIN OUTCOME MEASURES

Odds ratios (ORs) for each exposure on vision-threatening diabetic complications requiring vitrectomy.

RESULTS

The absence of panretinal photocoagulation was the primary significant individual-focused risk factor for vitrectomy in the multivariable analysis (OR, 4.78; P = 0.011). Systems-focused risk factors included longer interval between PDR diagnosis and initial treatment (weeks; OR, 1.06; P = 0.024) and greater cumulative duration of loss-to-follow-up during intervals of active PDR (months; OR, 1.10; P = 0.002). Greater duration in the ophthalmology system was the primary systems-focused protective factor against vitrectomy (years; OR, 0.75; P = 0.035).

CONCLUSIONS

Largely modifiable variables modulate risk of complications requiring diabetic vitrectomy. Each additional month of loss-to-follow-up for patients with active proliferative disease increased odds of vitrectomy by 10%. Optimizing modifiable factors to promote earlier treatment and maintain critical follow-up in proliferative disease may reduce vision-threatening complications requiring vitrectomy in a safety-net hospital setting.

FINANCIAL DISCLOSURE(S)

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

Association of Male Sex and Microvascular Alterations on Optical Coherence Tomography Angiography in Diabetes

Purpose

Epidemiologically, men have a higher incidence, severity, and progression of diabetic retinopathy (DR) than women. We investigated microvascular differences between men and women with diabetes on optical coherence tomography angiography (OCTA).

Methods

Three × 3 mm OCTA macula scans of non-diabetic and patients with diabetes were obtained. Vascular parameters included parafoveal vessel density (VD), vessel length density (VLD), and flow index (FI) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) as well as foveal avascular zone (FAZ) area and perimeter. Multivariable linear regression was used for statistical analysis.

Results

There were 1809 patients with diabetes and 217 non-diabetic participants that were included in this study. Diabetic individuals included those with no DR (n = 1356), mild non-proliferative DR (NPDR; n = 286), moderate NPDR (n = 126), and severe NPDR/proliferative DR (PDR; n = 41). Male sex was significantly associated with smaller FAZ area/perimeter and lower DCP VLD in both non-diabetic subjects and patients with diabetes. Male sex in the diabetic group was additionally associated with lower SCP VD/VLD and DCP VD. Addition of an interaction between male sex and diabetes status in the interaction analysis showed that being male and diabetic conferred increased reduction in DCP VD and VLD compared to sex-based changes in non-diabetics. Larger FAZ perimeter, lower SCP VD/VLD, and lower DCP VLD were associated with poorer visual acuity in diabetics.

Conclusions

On OCTA, male patients with diabetes may have more severe microvascular disease especially in the DCP compared to women.

Translational Evidence

Sex-based alterations in diabetic microvascular disease has the potential to influence future basic and clinical studies as well as the implementation of OCTA disease markers.

Ultra-Widefield Imaging as a Teleophthalmology Screening Tool for Ocular Pathology

Background

Prior studies have validated ultra-widefield imaging as a remote screening tool for diabetic retinopathy. The aim of this study was to determine its use in screening for any fundus pathology in a routine patient population.

Methods

In this prospective randomized study, patients underwent both slit lamp indirect ophthalmoscopy and ultra-widefield imaging. Ultra-widefield images were independently reviewed by two optometrists, and discrepancies were adjudicated by a retina specialist. Clinical findings from slit-lamp examiners and image-reviewers were coded into themes and clinically meaningful findings were extracted. Cohen's kappa was used to estimate agreement for these findings between the two image-reviewers and between the image-reviewers and slit-lamp examiners.

Results

Nine-hundred eyes of 450 patients were examined and imaged, of which 616 eyes were analyzed. At least one abnormal fundus finding was present on ophthalmoscopy in 71 eyes (11%) and on adjudicated image interpretation in 166 eyes (27%). Agreement between the two image-reviewers was moderate to substantial for most clinically meaningful findings, including optic disc hemorrhage (κ = 0.8), macular exudates (κ = 0.7), and macular pigmentary changes (κ = 0.7). Agreement between examiners and image-reviewers was moderate to substantial for optic disc hemorrhage (κ = 1), indistinct optic disc margins (κ = 0.5), drusen (κ = 0.4), pigmentary changes (κ = 0.4), and hemorrhage (κ = 0.8). A total of 187 findings were detected by imaging but not examination, compared with 42 that were detected on examination but not imaging.

Conclusion

In a routine patient population, ultra-widefield imaging agreed with standard-of-care slit-lamp examinations and detected more fundus findings.

Efficacy of the Fluocinolone Acetonide (Yutiq) Intravitreal Implant as Monotherapy for Uveitis

PURPOSE

To evaluate the efficacy of the fluocinolone acetonide intravitreal implant (Yutiq) as monotherapy for uveitis.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients at a single academic health-care institution.

METHODS

Medical record review of patients with non-infectious uveitis actively suppressed on an alternative anti-inflammatory regimen who received a fluocinolone acetonide implant. The primary outcome was continued control of inflammation based on clinical examination, optical coherence tomography, and fluorescein angiography.

RESULTS

Thirteen patients (19 eyes) received an implant. Median follow-up was 6 months. Uveitis control was achieved in 14 eyes (74%), though three (21%) required a topical steroid after insertion. The remaining five eyes (26%) required additional intraocular treatments.

CONCLUSION

The fluocinolone acetonide implant may not suffice as monotherapy for all patients with uveitis, but it may be effective as an adjunctive treatment. We propose a clinical workflow for the selection and treatment of patients who may benefit from it.

Modified intrascleral haptic fixation of the light adjustable lens in a case of spontaneous adult-onset bilateral lens subluxation

Purpose

To describe the application of the light adjustable lens (LAL) using an intrascleral haptic fixation (ISHF) technique for the correction of aphakia and post-operative refractive error.

Observation

The LAL was placed using a modified trocar-based ISHF technique for visual rehabilitation following removal of bilateral cataracts in a patient with ectopia lentis. She ultimately obtained an excellent refractive outcome after adjustment with micro-monovision.

Conclusions and Importance

Secondary intraocular lens placement has a much higher risk of residual ametropia than traditional in-the-bag lens placement. The ISHF technique with the LAL presents a solution for eliminating postoperative refractive error in patients requiring scleral-fixated lenses.

Aqueous Fluid Transcriptome Profiling Differentiates Between Non-Neovascular and Neovascular AMD

Purpose

Early and intermediate non-neovascular AMD (NN-AMD) has the potential to progress to either advanced NN-AMD with geographic atrophy, or to neovascular AMD (N-AMD) with CNV. This exploratory study performed an unbiased analysis of aqueous humor transcriptome in patients with early or intermediate NN-AMD vs. treatment-naïve N-AMD to determine the feasibility of using this method in future studies investigating pathways and triggers for conversion from one form to another.

Methods

Aqueous humor samples were obtained from 20 patients with early or intermediate NN-AMD and 20 patients with untreated N-AMD, graded on clinical examination and optical coherence tomography. Transcriptome profiles were generated using next-generation sequencing methods optimized for ocular samples. Top-ranked transcripts were compared between groups, and pathway enrichment analysis was performed.

Results

Seventy-eight differentially expressed transcripts were identified. Unsupervised clustering of differentially expressed transcripts was able to successfully differentiate between the two groups based on aqueous transcriptome alone. Pathway analysis highlighted changes in expression of genes associated with mitochondrial respiration, oxidative stress, ubiquitination, and neurogenesis between the two groups.

Conclusions

This pilot study compared the aqueous fluid transcriptome of patients with early or intermediate NN-AMD and untreated N-AMD. Differences in transcripts and transcriptome pathways identified in the aqueous of patients with early or intermediate NN-AMD compared with patients with N-AMD are consistent with those previously implicated in the pathogenesis of these distinct AMD subtypes. The findings from this exploratory study warrant further investigation using a larger, prospective study design, with the inclusion of a control group of eyes without AMD.

Right versus left eye asymmetry of microvasculature in diabetes revealed by optical coherence tomography angiography

In this study, we explored inter-ocular asymmetry (between the two eyes of the same patient) using optical coherence tomography angiography (OCTA) in patients with diabetes mellitus (DM) at different retinopathy stages. A total of 258 patients were divided into four groups: no DM, DM without diabetic retinopathy (DR), non-proliferative DR (NPDR), and proliferative DR (PDR). Superficial and deep vessel density (SVD, DVD), superficial and deep perfusion density (SPD, DPD), foveal avascular zone (FAZ) area, perimeter and circularity were calculated, and asymmetry index (AI) was used to evaluate the asymmetry of two eyes of the same subject. AIs of SPD, SVD, FAZ area and FAZ perimeter in the PDR group were larger than all other 3 groups (all p < 0.05). The AIs of DPD, DVD, FAZ area and FAZ perimeter in males were larger than in females (p = 0.015, p = 0.023, p = 0.006 and p = 0.017). Hemoglobin A1c (HbA1c) was positively correlated with AI of FAZ perimeter (p = 0.02) and circularity (p = 0.022). In conclusion, PDR patients' eyes were significantly asymmetric in both vascular density and FAZ metrics. Male sex and HbA1c are risk factors that influenced symmetry. This study highlights that right-left asymmetry should be taken into account in DR-related studies, particularly those analyzing microvascular changes with OCTA.

Developing and Validating Models to Predict Progression to Proliferative Diabetic Retinopathy

Purpose

To develop models for progression of nonproliferative diabetic retinopathy (NPDR) to proliferative diabetic retinopathy (PDR) and determine if incorporating updated information improves model performance.

Design

Retrospective cohort study.

Participants

Electronic health record (EHR) data from a tertiary academic center, University of California San Francisco (UCSF), and a safety-net hospital, Zuckerberg San Francisco General (ZSFG) Hospital were used to identify patients with a diagnosis of NPDR, age ≥ 18 years, a diagnosis of type 1 or 2 diabetes mellitus, ≥ 6 months of ophthalmology follow-up, and no prior diagnosis of PDR before the index date (date of first NPDR diagnosis in the EHR).

Methods

Four survival models were developed: Cox proportional hazards, Cox with backward selection, Cox with LASSO regression and Random Survival Forest. For each model, three variable sets were compared to determine the impact of including updated clinical information: Static₀ (data up to the index date), Static_6m (data updated 6 months after the index date), and Dynamic (data in Static₀ plus data change during the 6-month period). The UCSF data were split into 80% training and 20% testing (internal validation). The ZSFG data were used for external validation. Model performance was evaluated by the Harrell's concordance index (C-Index).

Main Outcome Measures

Time to PDR.

Results

The UCSF cohort included 1130 patients and 92 (8.1%) patients progressed to PDR. The ZSFG cohort included 687 patients and 30 (4.4%) patients progressed to PDR. All models performed similarly (C-indices ∼ 0.70) in internal validation. The random survival forest with Static_6m set performed best in external validation (C-index 0.76). Insurance and age were selected or ranked as highly important by all models. Other key predictors were NPDR severity, diabetic neuropathy, number of strokes, mean Hemoglobin A1c, and number of hospital admissions.

Conclusions

Our models for progression of NPDR to PDR achieved acceptable predictive performance and validated well in an external setting. Updating the baseline variables with new clinical information did not consistently improve the predictive performance.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Longitudinal fundus imaging and its genome-wide association analysis provide evidence for a human retinal aging clock

Biological age, distinct from an individual's chronological age, has been studied extensively through predictive aging clocks. However, these clocks have limited accuracy in short time-scales. Here we trained deep learning models on fundus images from the EyePACS dataset to predict individuals' chronological age. Our retinal aging clocking, 'eyeAge', predicted chronological age more accurately than other aging clocks (mean absolute error of 2.86 and 3.30 years on quality-filtered data from EyePACS and UK Biobank, respectively). Additionally, eyeAge was independent of blood marker-based measures of biological age, maintaining an all-cause mortality hazard ratio of 1.026 even when adjusted for phenotypic age. The individual-specific nature of eyeAge was reinforced via multiple GWAS hits in the UK Biobank cohort. The top GWAS locus was further validated via knockdown of the fly homolog, Alk, which slowed age-related decline in vision in flies. This study demonstrates the potential utility of a retinal aging clock for studying aging and age-related diseases and quantitatively measuring aging on very short time-scales, opening avenues for quick and actionable evaluation of gero-protective therapeutics.

Proximity Extension Assay (PEA) Platform to Detect Vitreous Biomarkers of Diabetic Retinopathy

Diabetic retinopathy (DR) is one of the leading causes of blindness, affecting more than 100 million people worldwide. Currently, DR prognosis and management are based mainly on biomarkers identified by direct retinal fundus observation or by imaging devices. The use of molecular biology to discover biomarkers of DR has great potential to impact the standard of care, and the vitreous humor can serve as an indirect source for those molecular biomarkers because it is rich in proteins secreted by the retina. Proximity extension assay (PEA) is a technology that combines antibody-based immunoassays with DNA-coupled methodology to obtain information on the abundance of multiple proteins while using minimal sample volume, with high specificity and sensitivity. Matched antibodies labelled with a complementary sequence of oligonucleotides are used to simultaneously bind a target protein in solution, and when in proximity, the complementary sequences on each antibody hybridize, serving as template for DNA polymerase-dependent extension and the generation of a unique double-stranded DNA "barcode." PEA works well with vitreous matrix and has great potential to support the identification of novel predictive and prognostic biomarkers of DR.

Rapid pre-retinal ossification presenting as a vascularized lesion over an area of chronic retinal detachment

Purpose

To describe the clinical, optical coherence tomography (OCT), and histopathological findings of a patient who was found to have ossification of a pre-retinal membrane after multiple surgical repairs for retinal detachment.

Methods

The patient had comprehensive ophthalmic examinations during seven years of follow-up and underwent surgical removal of her pre-retinal membrane.

Results

A 24-year-old woman with a history of retinal detachment and multiple retina surgeries presented with baseline vision of 20/200 and refractory glaucoma in the left eye (right eye with no light perception due to prior failed retinal detachment repair). OCT showed a thick epiretinal membrane with hypo-reflective intraretinal spaces in the macula, and exam revealed a chronic retinal detachment superotemporally surrounded by laser barricade. She was stable for six years and then experienced vision loss and decreasing eye pressure, concurrent with rapid evolution of pre-retinal fibrosis, leading to a vascularized consolidation in the mid-periphery, for which she underwent vitrectomy and membrane peel. The vascularized lesion over the area of detachment in the superotemporal retina was removed en bloc through the anterior chamber. Pathological findings revealed woven bone formation anterior to the internal limiting membrane, and the tissue was GFAP negative.

Conclusions

Our case adds to the limited knowledge of the chronology, presentation, and surgical management of intraocular ossification, especially of the rarer pre-retinal type. Our patient highlights that development of ossification can happen more quickly than previously thought (year or years rather than decades), can be hidden under vascularized lesions, and is dynamic, with simultaneous release of traction in one area and increased traction in another. Diligent follow-up is indicated even in cases of vitreous membranes from retinal detachment that otherwise appear to have been stable for years.

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.

Late-onset Etanercept-associated Ocular Sarcoidosis with Profound Vision Loss

INTRODUCTION

Etanercept is a tumor necrosis factor-alpha-blocking immunosuppressive agent and carries the risk of paradoxical induction of sarcoidosis. We present a case of a 75-year-old woman with rheumatoid arthritis treated with etanercept who developed etanercept-associated ocular sarcoidosis after 4 years of therapy.

CASE REPORT

The patient presented to clinic with visual acuity of light perception in the right eye and hand motions in the left eye. Examination revealed optic disc edema in both eyes with serous retinal detachment in the right eye. Work-up revealed an elevated serum angiotensin-converting enzyme level, and computed tomographic scan of the chest revealed innumerable bilateral peribronchial pulmonary nodules with calcifications. A diagnosis of presumed ocular sarcoidosis was made. Etanercept was stopped, and the patient was treated with oral prednisone and subcutaneous methotrexate, with clinical and visual recovery.

CONCLUSIONS

Etanercept-associated sarcoidosis can occur at any time after initiating therapy and should be considered in patients on etanercept with ocular inflammation.

The Port Delivery System with ranibizumab: a new paradigm for long-acting retinal drug delivery

The Port Delivery System with ranibizumab (PDS) is an innovative intraocular drug delivery system designed for the continuous delivery of ranibizumab into the vitreous for 6 months and beyond. The PDS includes an ocular implant, a customized formulation of ranibizumab, and four dedicated ancillary devices for initial fill, surgical implantation, refill-exchange, and explantation, if clinically indicated. Ranibizumab is an ideal candidate for the PDS on account of its unique physicochemical stability and high solubility. Controlled release is achieved via passive diffusion through the porous release control element, which is tuned to specific drug characteristics to accomplish a therapeutic level of ranibizumab in the vitreous. To characterize drug release from the implant, release rate was measured in vitro with starting concentrations of ranibizumab 10, 40, and 100 mg/mL, with release of ranibizumab 40 and 100 mg/mL found to remain quantifiable after 6 months. Using a starting concentration of 100 mg/mL, active release rate at approximately 6 months was consistent after the initial fill and first, second, and third refills, demonstrating reproducibility between implants and between multiple refill-exchanges of the same implant. A refill-exchange performed with a single 100-µL stroke using the refill needle was shown to replace over 95% of the implant contents with fresh drug. In vitro data support the use of the PDS with fixed refill-exchange intervals of at least 6 months in clinical trials.

Implant Insertion Procedure of the Port Delivery System With Ranibizumab: Overview and Clinical Pearls

OBJECTIVE

To describe the Port Delivery System with ranibizumab implant insertion procedure.

METHODS

A surgical procedure based on the clinical trial program in patients with retinal diseases.

RESULTS

An infusion line is placed in the infero-temporal quadrant; a superotemporal quadrant corneal traction suture is recommended. The superotemporal quadrant peritomy of 6 × 6 mm is executed with gentle, purposeful tissue handling. Generous posterior and lateral sub-Tenon's capsule dissection creates laxity for the subsequent closure. Adequate scleral hemostasis is achieved with wet-field cautery to maintain a clean field. The implant is filled under magnification with a customized formulation of ranibizumab. A precise 3.5-mm-long scleral incision (4 mm posterior and parallel to the limbus) is created to ensure proper implant fit. The exposed pars plana undergoes laser ablation to reduce vitreous hemorrhage risk. A pars plana incision is made, and the implant is inserted perpendicular to the globe and seated flush against the sclera. Complete closure of both the conjunctiva and Tenon's capsule with scleral anchoring and mild tissue overhang at the anterior limbus is performed to reduce conjunctival erosion and retraction risks.

CONCLUSION

The procedure is straightforward yet requires precise preoperative and intraoperative preparation and standardized surgical techniques. [Ophthalmic Surg Lasers Imaging Retina. 2022;53:249-256.].

Keratoprosthesis, silicone oil placement, and fluocinolone acetonide implant for treatment of uveitis-associated hypotony and keratopathy

Purpose

To describe a case series of combined Boston Type 1 Keratoprosthesis with pars plana vitrectomy, silicone oil placement, and fluocinolone acetonide intravitreal 0.59 mg implant (RETISERT®), and report its safety and efficacy in preventing phthisis bulbi in patients with uveitis-associated hypotony and concurrent corneal edema.

Findings

A retrospective review of patients with chronic uveitis, corneal decompensation and concurrent hypotony who underwent the combined approach described here between 2015 and 2020 was conducted. Three patients were treated using the combined approach. Post-operative recovery was unremarkable in all cases and the patients’ corneal condition remained stable on follow up. No patient developed phthisis, retroprosthetic membrane, or infectious endophthalmitis. Average intraocular pressure one year after intervention was 2.7 to 6.4 mmHg higher compared to a year prior.

Conclusions

The approach described is potentially safe and effective in preventing phthisis and membrane formation in uveitis-associated hypotony and keratopathy.

Factors associated with the development of blepharoptosis after pars plana vitrectomy surgery

PURPOSE

To determine the incidence and risk factors for developing blepharoptosis after vitrectomy surgery.

METHODS

This prospective observational study conducted in patients who had vitrectomy surgery at the University of California, San Francisco. The patients' eyelids were photographed before, surgery and follow-up visits at 1 day, 1 week, 1 month, 3 months, and 6 months after surgery. Levator excursion (LE), palpebral fissure (PF) height and marginal reflex distance 1 (MRD1) changes from baseline were evaluated. Operative parameters associated with lid parameter changes were analyzed.

RESULTS

Thirty-eight eyes were enrolled in the study. Multivariate analysis performed for PF changes from pre-operative were -0.47 mm, 0.33 mm, and 0.09 mm at 1 week, 1 month and 6 months after surgery, respectively (p-value 0.1, 0.2, and 0.8). The mean change of LE from preoperative was -0.44 mm, -0.15 mm, and 0.35 mm at 1 week, 1 month and 6 months after surgery, respectively (p-value 0.3, 0.7 and 0.4). The reduction of MRD1 at 1 week, 1 month and 6 months after surgery were -0.08 mm, -0.13 mm and -0.01 mm, respectively (p = .003, p = .6 and 0.9). Triamcinolone usage was associated with reduction of MRD1 and LE.

CONCLUSION

Blepharoptosis presents most during the first week after surgery. The possibility of developing transient changes in eyelid position after vitrectomy surgery should be discussed with patients.

TRANSIENT PARADOXICAL WORSENING OF VISION DUE TO GRAVITATIONAL SHIFT OF SUBRETINAL FLUID AFTER PHOTODYNAMIC THERAPY FOR CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To report an atypical treatment-related complication from photodynamic therapy in central serous chorioretinopathy patient and explain its mechanism.

METHODS

History, physical examination, and imaging data were retrospectively reviewed and obtained from the electronic medical records of the patient.

RESULTS

A central serous chorioretinopathy patient with several focal leakage spots near the superotemporal arcade was treated with half-fluence verteporfin photodynamic therapy. The patient complained of worse vision after the treatment. Examination showed relocation of subretinal fluid from the superior macula to the central and submacular area, explained by a gravitational shift of subretinal fluid and the predisposing factor of a previously weakened junction between the retinal pigment epithelium and neurosensory retina. Without further treatment, the fluid reabsorbed, and the patient's vision returned to normal.

CONCLUSION

This is the first report to describe this transient atypical adverse visual outcome early after photodynamic therapy in a central serous chorioretinopathy patient, caused by a gravitational shift of viscous subretinal fluid.

Racial and ethnic differences in foveal avascular zone in diabetic and nondiabetic eyes revealed by optical coherence tomography angiography

Purpose

The purpose of this study was to examine whether racial and ethnic differences in retinal microvasculature are detectable with quantitative measures derived from optical coherence tomography angiography (OCTA).

Methods

OCTA scans and fundus photography were obtained in 447 eyes from 271 patients with and without diabetes between April and October 2018. Fundus photos were graded by the hospital reading center for diabetic retinopathy (DR) severity. Eight OCTA parameters relating to the foveal avascular zone (FAZ), superficial vascular perfusion, and deep vascular perfusion were analyzed for significant differences between race and ethnicity groups, self-reported by patients and organized according to National Center for Health Statistics groupings. Multiple regression was then used to adjust estimates for possible confounding by age, gender, hypertension, and last hemoglobin A1c level.

Results

Significant differences in FAZ area were found between white and non-white patients. After adjustment, the differences between white and all non-white groups were statistically significant (p<0.05) among patients with mild to moderate DR. In those without diabetes, the Hispanic and Asian groups had significantly larger FAZ areas (p<0.005) than NH white patients. In those with mild to moderate non-proliferative diabetic retinopathy (NPDR), NH Black, Hispanic, and Asian patients also had significantly larger FAZ areas than NH white patients (p<0.005).

Conclusion

Significant differences in FAZ area exist among different racial and ethnic groups. These results highlight the importance of considering and further studying race and ethnicity in OCTA analyses of the retinal microvasculature.

Association between smoking history and optical coherence tomography angiography findings in diabetic patients without diabetic retinopathy

Purpose

To investigate any associations between cigarette smoking and retinal microvascular changes in diabetic patients without visible retinopathy.

Design

Retrospective, cross-sectional study.

Participants

1099 eyes from 1099 diabetic patients with no clinical evidence of diabetic retinopathy (DR) were included in this study.

Methods

Diabetic patients underwent optical coherence tomography angiography (OCTA) scanning at Zuckerberg San Francisco General Hospital and Trauma Center between April 2018 and September 2019. Patient demographic and clinical information was collected. Standard bivariate statistics and multivariate linear regression were performed.

Main outcome measures

OCTA parameters included metrics related to the foveal avascular zone (FAZ; area, perimeter, circularity), perfusion density (PD; full, center, inner), and vessel length density (VLD; full, center, inner).

Results

The study population included 750 non-smokers and 349 smokers. FAZ perimeter was the only OCTA parameter that was significantly different between the two groups on uncontrolled analysis (P = 0.033). Multivariate regression analyses revealed significant associations between lower VLD full (β = -0.31, P = 0.048), lower VLD inner (β = -0.35, P = 0.046) and a history of smoking. No significant associations between cigarette smoking and either FAZ or PD were detected.

Conclusions

Our results suggest that smoking is likely associated with deleterious changes in the retinal microvasculature of patients with a history of diabetes and no visible DR. Based on these findings, diabetic patients with a history of smoking may benefit from higher prioritization in terms of ophthalmic screening.

Sex-Based Analysis of Potential Inflammation-Related Protein Biomarkers in the Aqueous Humor of Patients With Diabetes Mellitus

Purpose

To investigate whether men have higher inflammatory protein biomarker concentrations in their aqueous humor (AH) compared with women in groups of patients with varying levels of diabetic disease.

Methods

This cross-sectional study included AH specimens from 59 adult patients comprised of three groups: no diabetes mellitus (DM), DM without diabetic retinopathy (DR), and DM with proliferative diabetic retinopathy (PDR). Protein biomarker concentration values were quantified using a commercial proximity extension assay-based technique.

Results

Intersex comparisons of concentration values for each protein biomarker revealed no discoveries in patients with no DM or with PDR. In contrast, 24 discoveries were detected in patients with DM without DR. The mean concentration value for all 24 protein biomarkers was higher in men compared with women. Of these 24 proteins, 12 demonstrated a significant association with sex on multivariate linear regression analysis. The β coefficient results demonstrated a positive association between male sex and concentration value for all 12 of these proteins.

Conclusions

Higher AH concentration levels of several potential biomarkers, including chemokines, proteases, proteins involved in programmed cell death, and a T-cell surface protein, were detected in men with DM with no DR. These findings suggest that men may have a more inflammatory disease phenotype compared with women in this group of patients.

Translational Relevance

The findings of this study help explain differences in epidemiologic patterns of diabetic retinopathy development between men and women.

Modified technique for trocar-based sutureless scleral fixation of intraocular lenses: A new approach to haptic externalization

Purpose

To describe a modified technique of haptic externalization for trocar-based sutureless scleral fixation of intraocular lenses, in order to avoid working with forceps in the iris plane in a manner that may be unfamiliar to the vitreoretinal surgeon.

Methods

This prospective, interventional case series included four eyes of four patients with dislocated intraocular lens (IOL). The modified haptic externalization technique avoids the pitfalls of iris-plane maneuvers by intentionally dropping the IOL onto the retina and using the forceps to grasp the tips of the haptics prior to direct externalization from the same grab.

Results

Four patients underwent scleral fixation of IOL using modified haptic externalization technique. One patient was lost to follow up after postoperative day 1. At the last follow up, all eyes demonstrated stability and good centration of scleral fixated IOL. All three patients achieved a best corrected visual acuity same or better compared to before the operation. One patient developed vitreous hemorrhage which later spontaneously resolved.

Conclusions

The modified haptic externalization technique is a simple and quick modification using maneuvers familiar to vitreoretinal surgeons. It has demonstrated safety among a small pilot group of patients.

Corneal Toxicity of Intravitreal Methotrexate Used for the Treatment of Proliferative Vitreoretinopathy in Silicone Oil-Filled Eyes: A Case Series

PURPOSE

The purpose of this study was to evaluate the corneal toxicity of intravitreal methotrexate used for the prevention of proliferative vitreoretinopathy (PVR).

METHODS

In this retrospective case series, eyes with recurrent retinal detachment secondary to PVR were treated with intravitreal injections of 400 μg methotrexate at an average frequency of every 7 days after vitrectomy with silicone oil tamponade. Corneas were examined for corneal epitheliopathy by slit-lamp biomicroscopy before each injection.

RESULTS

Thirteen eyes of 12 patients were reviewed. All had a history of recurrent retinal detachment secondary to PVR treated with vitrectomy and silicone oil. The median age was 35 years (range: 9-83). Four patients (33%) were female. The median follow-up duration was 8 weeks (range: 5-10). The median BCVA (logMAR notation) was 2.00 preoperatively, 2.00 at 1 month postoperatively, and 2.00 at the most recent follow-up (P = 0.969). Ten eyes (77%) were pseudophakic. Nine eyes (69%) had a preexisting ocular comorbidity. The median number of injections was 8 (range: 5-10). The median interval time between each injection was 7.0 days (range: 5.8-10.5), and the median follow-up period beyond last injection was 16 weeks (range: 8-28). Two eyes (15.4%) developed mild corneal epitheliopathy during the course of the treatment.

CONCLUSIONS

Most eyes in this small series tolerated methotrexate injections without corneal toxicity. In eyes that developed epitheliopathy, the findings were mild and not treatment-limiting.

Optical Coherence Tomography Angiography Assessment of Macular Choriocapillaris and Choroid Following Panretinal Photocoagulation in a Diverse Population With Advanced Diabetic Retinopathy

PURPOSE

The aim of this study was to evaluate choroidal and retinal microvasculature with optical coherence tomography angiography (OCTA) after panretinal photocoagulation (PRP) for diabetic retinopathy in a primarily Hispanic and Asian population.

DESIGN

Retrospective study.

METHODS

Eyes were examined by OCTA in the macula (3 × 3 mm) just before PRP treatment and 1 to 3 months afterwards. Choroidal thickness (CT) and central retinal thickness (CRT) were measured. Choroidal flow signal voids (CFSV) and choriocapillaris flow signal voids (CCFSV) were acquired. Retinal microvasculature parameters, including superficial and deep vessel density, superficial and deeper perfusion density, foveal avascular zone area, perimeter and circularity, were calculated. Ocular examinations and demographic information were analyzed.

RESULTS

CT at a location 1000 μm temporal to the fovea increased significantly after PRP (from 278.64 μm to 313.44 μm, P = 0.026). CCFSV increased slightly from (46.72 ± 8.52)% to (47.07 ± 10.77)%, but the difference was not statistically significant (P = 0.782). A similar finding was observed in CFSV (increase from 35.81% to 36.64%, P = 0.165). The change in all retinal microvasculature parameters was also not significant. Best-corrected visual acuity (BCVA) decreased from 0.218 ± 0.153 to 0.262 ± 0.147 (P = 0.034). Increased CRT (from 245.41 ± 33.18 μm to 251.14 ± 38.97 μm, P = 0.007) was observed. The change in CRT positively correlated with pre-PRP CRT (r = 0.434, P = 0.019) and BCVA reduction (r = 0.418, P = 0.024). Neither BCVA reduction nor CRT increase correlated with OCTA metrics.

CONCLUSIONS

OCTA demonstrates redistribution of choroidal circulation from the periphery to the macula after PRP, with increased macular CT and stable choroidal blood flow density. Eyes with greater macular thickness are more likely to experience an increase in CRT.

Comparative Analysis of Multiplex Platforms for Detecting Vitreous Biomarkers in Diabetic Retinopathy

Purpose

To evaluate the feasibility of using the Proximity Extension Assay (PEA) platform to detect biomarkers in vitreous and to compare the findings with results obtained with an electrochemiluminescent (ECL) sandwich immunoassay.

Methods

Vitreous samples from patients with proliferative diabetic retinopathy (PDR) and non-diabetic controls were tested using two different proteomics platforms. Forty-one assays were completed with the ECL platform and 459 with the PEA platform. Spearman's rank correlation coefficient (r_s) was used to determine the direction and strength of the relationship between protein levels detected by both platforms.

Results

Three hundred sixty-six PEA assays detected the tested protein in at least 25% of samples, and the difference in protein abundance between PDR and controls was statistically significant for 262 assays. Seventeen ECL assays yielded a detection rate ≥ 25%, and the difference in protein concentration between PDR and controls was statistically significant for 13 proteins. There was a subset of proteins that were detected by both platforms, and for those the Spearman's correlation coefficient was higher than 0.8.

Conclusions

PEA is suitable for the analysis of vitreous samples, showing a strong correlation with the ECL platform. The detection rate of PEA panels was higher than the panels tested with ECL. The levels of several proinflammatory and angiogenic cytokines were significantly higher in PDR vitreous compared to controls.

Translational Relevance

This study provides new information on the yields of small-volume assays that can detect proteins of interest in ocular specimens, and it identifies patterns of cytokine dysregulation in PDR.

Delayed Acute Granulomatous Anterior Uveitis after Inadvertent Intraocular Injection of Tattoo Ink from a Scleral Tattoo Procedure

PURPOSE

To improve awareness of delayed onset uveitis in patients with a history of intraocular tattoo ink injection.

RESULTS

A 47-year-old man underwent a scleral tattoo procedure during which there was inadvertent intraocular injection of tattoo ink into his right eye. He subsequently developed endophthalmitis, retinal detachment, and retinal necrosis. He was treated with intravitreal and oral antibiotics and underwent vitreoretinal surgical intervention. A vitreous specimen was obtained and demonstrated significantly elevated levels of several heavy metals. One month later, he developed an acute granulomatous anterior uveitis in the same eye that was managed with a combination of topical and perioperative intravitreal, intravenous, and oral corticosteroids.

CONCLUSION

This case highlights the importance of monitoring patients with a history of intraocular tattoo ink injection for delayed onset uveitis in addition to retinal toxicity.

Discordant vascular parameter measurements in diabetic and non-diabetic eyes detected by different optical coherence tomography angiography devices

PURPOSE

To compare quantitative changes in macular parameters in diabetic patients detected by two optical coherence tomography angiography (OCTA) instruments.

METHODS

80 phakic eyes were classified as no diabetes, diabetes without diabetic retinopathy (DR), mild non-proliferative diabetic retinopathy (NPDR), and severe NPDR or proliferative DR (PDR). OCTA was performed using devices from two manufacturers (Zeiss and Heidelberg). Superficial and deeper vascular skeleton density (SVSD, DVSD), superficial and deeper vessel area density (SVAD, DVAD), choriocapillaris flow voids (CCFV), and choroidal flow voids (CFV) were calculated. Inter-device comparisons were performed using the size comparison index (SCI) and the discrepancy index (DI).

RESULTS

The two devices were inconsistent in SVSD, DVSD, DVAD, CCFV and CFV parameters (all P < 0.05). In addition, the SCI was positive for DVAD (all P < 0.001) and negative for SVSD, DVSD, CCFV and CFV in all groups (all P <0.001), except for DVSD in severe NPDR or PDR. The discrepancy index was not significantly different among groups for SVD, SPD, DVD, DPD and CFV (all P> 0.05). The mean DI of CCFV was statistically different between the four groups (P < 0.001).

CONCLUSIONS

The two instruments were largely inconsistent in the measurement of macular parameters relevant to DR. The choice of imaging device can impact OCTA analytics and should be taken into account when drawing conclusions about DR-related changes.

Three-year outcomes of macular buckling for macular holes and foveoschisis in highly myopic eyes

BACKGROUND

To assess the functional and structural outcomes of macular buckling using a silicone sponge-titanium exoplant for the treatment of foveoschisis (FS) and full-thickness macular holes (FTMHs) in highly myopic eyes.

METHODS

Forty-nine consecutive patients with high myopia who underwent macular buckling for the treatment of FS and FTMHs were included. The outcomes measured included the anatomical success rate with FS resolution, retinal reattachment, MH closure, best corrected visual acuity (BCVA), axial length (AL) and complications of surgery. Moreover, the correlations between the BCVA at year three and series of factors, including age, duration of symptoms, baseline BCVA, AL, surgical type, preoperative macular status and severity of myopic maculopathy, were analysed.

RESULTS

This study involved 28 patients (28 eyes) with FS and 21 patients (21 eyes) with FTMHs with macular detachment. Retinal reattachment was achieved in 100% of cases, while MH closure was achieved in 76.19% of cases. The BCVA significantly improved one year after macular buckling in the FS cases and two years after macular buckling in the FTMH cases, and it remained stable throughout the rest of the follow-up period. The mean AL decreased by 2.09 mm postoperatively. No major perioperative complications were observed, although one patient needed to explant the buckling device due to intolerable diplopia.

CONCLUSION

Macular buckling with a silicone sponge-titanium exoplant may represent a safe and effective surgical option for the treatment of FS and FTMH in highly myopic eyes. Macular buckling showed a high closure rate and virtually no tendency to recur.

Correlation of Aqueous, Vitreous, and Plasma Cytokine Levels in Patients With Proliferative Diabetic Retinopathy

Purpose

To investigate the relationship between proangiogenic and inflammatory cytokines in concurrent vitreous, aqueous, and plasma samples from patients with proliferative diabetic retinopathy (PDR).

Methods

Vitreous, aqueous, and plasma samples were analyzed using multiplex immunoassay for 10 PDR-related cytokines (IL-6, IL-8, TNF-α, monocyte chemoattractant protein-1 [MCP-1], macrophage inflammatory protein-1β [MIP-1β], VEGF receptor 1 [Flt-1], placental growth factor [PlGF], VEGF-A, VEGF-C, VEGF-D). A total of 17 patients with PDR and 7 controls were included. The primary outcome was correlation of cytokines in vitreous, aqueous, and plasma. The secondary outcome was the comparison of cytokine levels in controls and diabetics with and without recent anti-VEGF injection.

Results

The following factors were elevated in diabetics compared with controls: vitreous IL-6, IL-8, TNF-α, MCP-1, MIP-1β, PlGF, and VEGF-A; and aqueous IL-6, IL-8, PlGF, and VEGF-C (all P < 0.05). Vitreous and aqueous IL-8, PlGF, and VEGF-A were significantly correlated in patients with PDR (all P < 0.05). Plasma cytokines were not correlated with those in vitreous and aqueous (all P > 0.05). Vitreous and aqueous IL-6, IL-8, TNF-α, PlGF, and VEGF-A differed among controls and diabetics with and without recent anti-VEGF injection (all P < 0.05). In one-to-one comparisons, aqueous VEGF-A levels were lower in diabetic patients who had recent anti-VEGF injection compared with those who did not (P = 0.01).

Conclusions

In this proof-of-concept study, IL-8, VEGF-A, and PlGF demonstrated a strong correlation in vitreous and aqueous of patients with PDR. The aqueous may serve as a proxy for vitreous for some cytokines involved in PDR. Recent anti-VEGF injections decreased VEGF-A levels in aqueous, but did not significantly affect other cytokines, suggesting a role for other targeted therapies in PDR management.

Effect of hypothermic perfusion on phacoemulsification in eyes with hard nuclear cataract: randomized trial

PURPOSE

To evaluate the effectiveness and safety of hypothermic perfusion in the phacoemulsification of hard nuclear cataract.

SETTING

Tertiary opthalmology center, China.

DESIGN

Laboratory study and prospective randomized clinical trial.

METHODS

Rabbits and patients with hard nuclear cataract underwent phacoemulsification with perfusion temperatures at 4°C or 24°C. Anterior segment optical coherence tomography (AS-OCT), corneal endothelial cell count (ECC), and cornea sections were observed before the rabbits' operation and 1 day and 7 days postoperatively. AS-OCT, corneal ECC, and anterior chamber (AC) inflammation were observed before the patients' operation and 1 day, 7 days, and 30 days postoperatively.

RESULTS

The study comprised 40 rabbits and 80 patients. In the animal models, the mean central corneal thickness (CCT) in the 4°C group (370.4 μm ± 45.5 [SD]) was thinner than in the 24°C group (496.7 ± 121.5 μm) 1 day postoperatively (P < .001). The mean AC inflammation reaction grade in the 4°C group (1.1 ± 0.9) was lower than in the 24°C group (2.2 ± 0.8) (P = .0333). In clinical trials, the mean CCT and incisional corneal thicknesses in the 4°C group (600.7 ± 51.8 μm and 859.2 ± 177.8 μm, respectively) were thinner than in the 24°C group (655.3 ± 85.0 μm and 955.9 ± 196.7 μm, respectively) (P < .001). The endothelial cell density (P = .036) and hexagonality (P = .001) were higher in the 4°C group. The mean AC inflammation reaction grade in the 4°C group (0.6 ± 0.6) was lower than in the 24°C group (1.3 ± 1.0) 1 day postoperatively (P = .004).

CONCLUSIONS

Hypothermic perfusion in phacoemulsification of hard nuclear cataract is safe and it can effectively protect corneal endothelium, decrease corneal edema, and reduce AC inflammation in the early postoperative stage.

OCT Angiography Assessment of Retinal Microvascular Changes in Diabetic Eyes in an Urban Safety-Net Hospital

PURPOSE

To determine whether quantitative OCT angiography (OCTA) parameters can be used to distinguish among eyes at various stages of diabetic retinopathy (DR) in an urban safety-net hospital population.

DESIGN

Prospective cross-sectional study.

PARTICIPANTS

Three hundred twenty-nine eyes from 329 patients were included in this study: 90 nondiabetic patients, 170 diabetic patients without DR, 57 diabetic patients with mild to moderate nonproliferative DR (NPDR), and 12 diabetic patients with severe NPDR to proliferative DR.

METHODS

Patients underwent OCTA imaging and ultra-widefield fundus photography at Zuckerberg San Francisco General Hospital and Trauma Center between April and October 2018. For participants with diabetes, imaging was classified according to DR severity by a telemedicine reading center. Eight OCTA parameters were analyzed. Perfusion density and vessel length density (VD) were examined from both the superficial capillary plexus (SCP) and deep capillary plexus. The other 4 parameters were examined only from the SCP. Total extrafoveal avascular area (tEAA) was based on the area of absent capillary vessels. Foveal avascular zone (FAZ)-related metrics consisted of FAZ area, FAZ circularity index, and FAZ acircularity index.

MAIN OUTCOME MEASURES

Area under the receiver operating characteristic curve (AUC) for OCTA parameters to distinguish among groups according to DR severity.

RESULTS

All OCTA parameters demonstrated a significant relationship with DR severity (P < 0.05). No significant difference was found when comparing nondiabetic participants versus diabetic participants without retinopathy. The FAZ area was the only metric that demonstrated a significant difference between genders: mean of 0.29±0.12 mm² in men and 0.34±0.13 mm² in women (P < 0.001). Receiver operating characteristic curve analyses showed that tEAA had the highest AUC when comparing various stages of the disease.

CONCLUSIONS

In this urban, public hospital population, quantification of retinal vascular findings with OCTA imaging was a useful means of distinguishing patients according to DR severity. Because these results were similar to those of other tertiary referral centers, it would be reasonable to perform further DR-related OCTA studies in this population and expect generalizable results.

Dexamethasone Intravitreal Implant Injection in Eyes with Comorbid Hypotony

PURPOSE

To evaluate outcomes in patients with hypotony treated with intravitreal dexamethasone implant (Ozurdex).

DESIGN

Retrospective cohort study.

PARTICIPANTS

Thirteen patients (15 eyes) that received a total of 99 dexamethasone implant injections on occasions at which the intraocular pressure was low, meeting the definition of statistical hypotony.

METHODS

The medical records of 13 patients (15 consecutive eyes) receiving 1 or more intravitreal dexamethasone implants between December 2014 and April 2017 were reviewed retrospectively. Hypotony was defined as intraocular pressure less than 6.5 mmHg. The indications for intravitreal dexamethasone implant injection were intermediate or posterior uveitis (86.7%), diabetic macular edema (13.3%), and/or cystoid macular edema (6.7%).

MAIN OUTCOME MEASURES

The primary outcome measures were safety outcomes and best visual acuity within 6 months of the final intravitreal dexamethasone implant injection in a hypotonous eye.

RESULTS

In 15 eyes (13 patients), 99 injections were administered to eyes under circumstances of hypotony. Uveitic cystoid macular edema or diabetic macular edema was reduced after treatment in all cases. No complications were noted during the injection procedure. Three complications were noted in 2 patients after injection. Pseudophakodonesis and mild vitreous hemorrhage immediately after injection were noted in 1 patient, and a case of delayed-onset vitreous hemorrhage with pigment release was noted in another. All 3 complications resolved without intervention. The primary end point of this study-mean visual acuity-was stable over the follow-up period. In patients with hypotony whose intraocular pressure normalized during the follow-up period, this was attributable to management of glaucoma surgery-related complications rather than an effect of the intravitreal dexamethasone implant.

CONCLUSIONS

Intravitreal dexamethasone implant injection is a reasonable treatment option for patients with comorbid hypotony in whom clinical findings warrant treatment with a sustained-delivery intravitreal steroid implant. Further studies, including imaging of zonules before and after intravitreal dexamethasone implant injection in a hypotonous eye, could help define risks to intraocular lens stability with this procedure.

Improved Outcomes in Patients with Retinal Detachment after Implementation of a Silicone Oil Registry and Phone Call Reminder System

PURPOSE

This retrospective study was performed to assess the clinical impact in reducing silicone oil (SO)-related complications such as keratopathy of a registry and appointment reminder system for patients with complicated retinal detachment (RD) who underwent pars plana vitrectomy (PPV) with SO tamponade.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 87 eyes of 87 patients who received SO tamponade were included.

METHODS

The study was carried out at Zuckerberg San Francisco General Hospital and Trauma Center (ZSFG). Patients were divided into those who received SO before (control group, n = 48) or after (treatment group, n = 39) implementation of an SO registry and patient reminder system in 2014. Patient records were reviewed to identify clinical characteristics and outcomes.

MAIN OUTCOME MEASURES

The primary outcome measure was the difference in the rate of loss to follow-up before versus after the implementation of the registry and reminder system. Secondary outcomes were the duration of SO tamponade, keratopathy rate, and intraocular pressure (IOP) at the last visit before SO removal.

RESULTS

Forty-eight patients were included in the control group, and 39 patients were included in the treatment group. The number of patients lost to follow-up was 23 (47.9%) in the control group versus 6 (15.4%) in the treatment group (P = 0.0015). The mean duration before SO removal was 79.6±91.7 weeks in the control group and 36.3±31.5 weeks in the treatment group (mean±standard deviation [SD]) (P = 0.015). Keratopathy developed in 33.3% of patients in the control group and 12.8% of patients in the treatment group (P = 0.0425). Mean IOP at the last visit before SO removal was 13.0±5.2 mmHg (mean±SD) in the control group and 13.3±7 mmHg (mean±SD) in the treatment group (P > 0.05).

CONCLUSIONS

A phone call appointment reminder system for patients with complicated RD who underwent PPV and SO tamponade reduced the rate of loss to follow-up and the duration of SO tamponade, correlating with a reduction in the rate of keratopathy.

A Novel Hybrid Fixed and Mobile Ultra-Widefield Imaging Program for Diabetic Teleretinopathy Screening

PURPOSE

To describe a new approach for telemedicine screening of diabetic retinopathy (DR) using a combination of a mobile ultra-widefield camera, mounted in a van and able to travel to areas of need, and several fixed-location cameras in high-volume clinics and to report predictors of DR in a diverse urban population of 2788 patients.

DESIGN

Cross-sectional study.

PARTICIPANTS

Two thousand seven hundred eighty-eight patients enrolled in the San Francisco Health Network who underwent DR screening using the novel hybrid telemedicine system.

METHODS

The study was carried out at Zuckerberg San Francisco General Hospital in the San Francisco Health Network. A van was specially equipped to allow an ultra-widefield fundus camera to be mounted inside, and the van was sent with a technician to primary care clinics throughout the city on a rotation schedule determined according to clinical need. Additional fundus cameras were placed in several high-volume clinic locations. Patient demographic and clinical information was collected at the time of screening. Photographs were transmitted to a reading center and were graded for DR and other findings by trained readers.

MAIN OUTCOME MEASURES

Prevalence of DR subtypes and odds ratios for development of DR and proliferative DR (PDR).

RESULTS

The hybrid mobile and fixed-location ultra-widefield camera screening system was able to be deployed to carry out the telemedicine screening program for diabetic patients throughout the city of San Francisco referred for screening during the period of the study. Of 2788 patients screened, 736 (27%) were found to have DR. Of these, 34 (5%) had PDR, and 702 (95%) had nonproliferative DR. In multivariate analysis, factors found to be associated with development of any DR were diabetes duration, hemoglobin A1C level, insulin use, and end-organ damage. Diabetes duration was the only factor associated with PDR.

CONCLUSIONS

Diabetic retinopathy screening can be accomplished in an urban setting using a combination of fixed-location and mobile ultra-widefield cameras to extend the reach of the screening opportunity throughout a health network. In a diverse group of patients, factors associated with DR and PDR were identified and support ongoing efforts to screen for retinopathy and maintain diabetic control.

Engineering immunomodulatory biomaterials for type 1 diabetes

A cure for type 1 diabetes (T1D) would help millions of people worldwide, but remains elusive thus far. Tolerogenic vaccines and beta cell replacement therapy are complementary therapies that seek to address aberrant T1D autoimmune attack and subsequent beta cell loss. However, both approaches require some form of systematic immunosuppression, imparting risks to the patient. Biomaterials-based tools enable localized and targeted immunomodulation, and biomaterial properties can be designed and combined with immunomodulatory agents to locally instruct specific immune responses. In this Review, we discuss immunomodulatory biomaterial platforms for the development of T1D tolerogenic vaccines and beta cell replacement devices. We investigate nano- and microparticles for the delivery of tolerogenic agents and autoantigens, and as artificial antigen presenting cells, and highlight how bulk biomaterials can be used to provide immune tolerance. We examine biomaterials for drug delivery and as immunoisolation devices for cell therapy and islet transplantation, and explore synergies with other fields for the development of new T1D treatment strategies.