A prospective, case controlled study of the natural history of diabetic retinopathy and maculopathy after uncomplicated phacoemulsification cataract surgery in patients with type 2 diabetes

AIM

To determine if uncomplicated phacoemulsification cataract surgery is associated with an accelerated rate of progression of diabetic retinopathy or maculopathy postoperatively.

METHODS

A prospective trial of 50 type 2 diabetics undergoing monocular phacoemulsification cataract surgery by a single consultant surgeon. The grade of diabetic retinopathy and diabetic maculopathy in the operated and non-operated fellow eye was assessed preoperatively and for 12 months postoperatively.

RESULTS

Overall, retinopathy progression was observed in 11 patients. In seven the retinopathy progressed in both eyes, in three it progressed in the operated eye alone, and in one it progressed in the fellow eye alone. Macular oedema was observed in 13 eyes postoperatively. Four had transient pseudophakic cystoid macular oedema and nine true diabetic maculopathy. Where maculopathy progressed it did so symmetrically in five patients, it progressed in the operated eye alone in four patients, and the fellow eye alone in two patients. There was no significant difference in the number of operated and fellow eyes whose retinopathy or maculopathy progressed postoperatively. In both the operated (OE) and non-operated (NoE) eyes retinopathy progression was associated with a higher mean HbA(1)C (OE p=0.003; NoE p=0.001) and insulin treatment (OE p=0.008, NoE p=0.04).

CONCLUSION

Uncomplicated phacoemulsification cataract surgery does not cause acceleration of diabetic retinopathy postoperatively and any progression that is observed probably represents the natural history of the disease. Although macular oedema is common after cataract surgery it may follow a benign course and in many patients the development of clinically significant macular oedema postoperatively probably represents natural disease progression rather than being a direct effect of surgery.

Ten-Year Treatment Outcomes of Neovascular Age-Related Macular Degeneration from Two Regions

PURPOSE

To report and compare 10-year treatment outcomes of vascular endothelial growth factor (VEGF) inhibitors for neovascular age-related macular degeneration (nAMD) from Australia and New Zealand (ANZ) and Switzerland.

DESIGN

Retrospective, comparative, interventional case series.

METHODS

We analyzed 712 treatment-naive eyes (ANZ, n = 474; Switzerland, n = 321) starting anti-VEGF for nAMD in routine clinical practice between January 1, 2006, and December 31, 2008, tracked in the prospectively designed observational database, the Fight Retinal Blindness! registry. The primary outcome was mean change in visual acuity (VA [in logMAR letters]) in eyes that completed 10 years of treatment.

RESULTS

The mean VA in 132 eyes (28%) from ANZ patients who completed 10 years of treatment dropped by 0.9 letters from baseline (95% confidence interval [CI], -4.9 to 3.1; P = 0.7) with 42% achieving ≥20/40, whereas the 37 eyes (12%) from Swiss subjects lost 14.9 letters (95% CI, -24 to -5.7; P < 0.001) with 35% achieving ≥20/40. Eyes from ANZ patients received more injections than eyes from Swiss subjects over 10 years (a median of 53 vs 42, respectively) from fewer visits with better disease control (proportion of visits with active disease: 38% vs 69%, respectively), suggesting a treat-and-extend regimen versus a pro re nata regimen (treatment given only when the lesion is active). Macular atrophy and subretinal fibrosis were the main reasons for 10 letter loss in the subset of eyes analyzed retrospectively. The mean VA of eyes from both regions that discontinued treatment within 10 years had fallen below the baseline at their final visit.

CONCLUSIONS

Eyes with nAMD may achieve satisfactory long-term visual outcomes if they receive adequate treatment. Central macular atrophy does not develop universally in eyes receiving long-term treatment with VEGF inhibitors as previously feared. Visual outcomes were better in eyes from ANZ patients, likely because they received more injections.

Cystoid macular oedema following cataract surgery: A review

Pseudophakic cystoid macular oedema (PCMO) remains a significant cause of compromised postoperative vision in contemporary cataract surgery. Well-established risk factors include intraoperative complications such as posterior capsule rupture and preoperative factors including: diabetes mellitus, uveitis, retinal vein occlusion, epiretinal membrane. The role of topical glaucoma medications in PCMO continues to be debated. Current treatment strategies largely target suppression of inflammation. Topical NSAIDs remain the mainstay in prophylaxis and treatment of PCMO. Topical corticosteroids are commonly used as monotherapy or in combination with NSAIDs. Unfortunately, high-quality trials are notably lacking for other PCMO treatment modalities such as: periocular corticosteroids, orbital floor triamcinolone, intravitreal triamcinolone, corticosteroid implants, intravitreal bevacizumab and pars-plana vitrectomy. A lack of consistency in defining PCMO and resolution of PCMO explains why even large systematic reviews may come to contradictory conclusions. This review explores the varied contemporary evidence-base in relation to the aetiology, diagnosis, prophylaxis and treatment of PCMO.

Visual function following photodynamic therapy for central serous chorioretinopathy: a comparison of automated macular microperimetry versus best-corrected visual acuity

BACKGROUND

The study compares the change in best-corrected visual acuity with the change in central retinal sensitivity before treatment and 6 months after treatment with photodynamic therapy in patients with symptomatic central serous chorio retinopathy.

DESIGN

Prospective, single-centre, interventional case series.

PARTICIPANTS

Eleven consecutive patients with previously untreated central serous chorio retinopathy.

METHODS

Patients had microperimetry and best-corrected visual acuity recorded before and 6 months after treatment with photodynamic therapy. Refracted best-corrected visual acuity was assessed at 2 m and adjusted to give the number of letters read at 1 m. Threshold microperimetry was performed by presenting a Goldman III stimulus to 29 points over the central 12° around fixation. Significant visual improvement at 6 months was defined as a best-corrected visual acuity ≥10 letters or, microperimetry change in mean retinal sensitivity ≥2 decibels (dB).

MAIN OUTCOME MEASURES

Improvement in best-corrected visual acuity compared with microperimetry following photodynamic therapy treatment in patients with central serous chorio retinopathy.

RESULTS

All patients reported a subjective improvement in vision and had complete resolution of subretinal fluid at 6 months. Two patients had a significant improvement in best-corrected visual acuity (mean ± SD +4.2 ± 5.8 letters), compared with all 11 patients who recorded a significant improvement in mean retinal sensitivity (mean ± SD 4.6 ± 1.9 dB) (P < 0.001).

CONCLUSIONS

These data suggest that compared with microperimetry, best-corrected visual acuity is underestimating the effectiveness of photodynamic therapy in the treatment of central serous chorio retinopathy.

Detection of smoking status from retinal images; a Convolutional Neural Network study

Cardiovascular diseases are directly linked to smoking habits, which has both physiological and anatomical effects on the systemic and retinal circulations, and these changes can be detected with fundus photographs. Here, we aimed to 1- design a Convolutional Neural Network (CNN), using retinal photographs, to differentiate between smokers and non-smokers; and 2- use the attention maps to better understand the physiological changes that occur in the retina in smokers. 165,104 retinal images were obtained from a diabetes screening programme, labelled with self-reported "smoking" or "non-smoking" status. The images were pre-processed in one of two ways, either "contrast-enhanced" or "skeletonized". Experiments were run on an Intel Xeon Gold 6128 CPU @ 3.40 GHz with 16 GB of RAM memory and a NVIDIA GeForce TiTan V VOLTA 12 GB, for 20 epochs. The dataset was split 80/20 for training and testing sets, respectively. The overall validation outcomes for the contrast-enhanced model were accuracy 88.88%, specificity 93.87%. In contrast, the outcomes of the skeletonized model were accuracy 63.63%, specificity 65.60%. The "attention maps" that were generated of the contrast-enhanced model highlighted the retinal vasculature, perivascular region and the fovea most prominently. We trained a customized CNN to accurately determine smoking status. The retinal vasculature, the perivascular region and the fovea appear to be important predictive features in the determination of smoking status. Despite a high degree of accuracy, the sensitivity of our CNN was low. Further research is required to establish whether the frequency, duration, and dosage (quantity) of smoking would improve the sensitivity of the CNN.

Patients Perceptions of Artificial Intelligence in Diabetic Eye Screening

PURPOSE

Artificial intelligence (AI) technology is poised to revolutionize modern delivery of health care services. We set to evaluate the patient perspective of AI use in diabetic retinal screening.

DESIGN

Survey.

METHODS

Four hundred thirty-eight patients undergoing diabetic retinal screening across New Zealand participated in a survey about their opinion of AI technology in retinal screening. The survey consisted of 13 questions covering topics of awareness, trust, and receptivity toward AI systems.

RESULTS

The mean age was 59 years. The majority of participants identified as New Zealand European (50%), followed by Asian (31%), Pacific Islander (10%), and Maori (5%). Whilst 73% of participants were aware of AI, only 58% have heard of it being implemented in health care. Overall, 78% of respondents were comfortable with AI use in their care, with 53% saying they would trust an AI-assisted screening program as much as a health professional. Despite having a higher awareness of AI, younger participants had lower trust in AI systems. A higher proportion of Maori and Pacific participants indicated a preference toward human-led screening. The main perceived benefits of AI included faster diagnostic speeds and greater accuracy.

CONCLUSIONS

There is low awareness of clinical AI applications among our participants. Despite this, most are receptive toward the implementation of AI in diabetic eye screening. Overall, there was a strong preference toward continual involvement of clinicians in the screening process. There are key recommendations to enhance the receptivity of the public toward incorporation of AI into retinal screening programs.

Oral fluorescein angiography with the scanning laser ophthalmoscope in diabetic retinopathy: a case controlled comparison with intravenous fluorescein angiography

AIM

To compare the performance of oral fundus fluorescein angiography with a confocal scanning laser ophthalmoscope (SLO) with intravenous fundus fluorescein angiography (IVFFA) with a fundus camera in the assessment of sight-threatening diabetic retinopathy.

PATIENTS AND METHODS

A total of 25 patients undergoing IVFFA to investigate their diabetic retinopathy were recruited. Participants returned 1 week later and an oral angiogram with the SLO was performed. Six facets of the oral and intravenous angiograms were scored and compared: visualization of the foveal avascular zone (FAZ); branch retinal identification; macular leakage; identification of microaneurysms in areas of macular leakage; peripheral nonperfusion, and leakage from neovascular complexes.

RESULTS

Compared to IVFFA, the FAZ was unreliably visualized with oral angiography (Kappa 0.1, 95% CI 0-0.3). In contrast, macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), identification of microaneurysms in areas of macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), and neovascular complexes (Kappa 1.0) were reliably seen. Analysis of the visualization of peripheral nonperfusion was complicated by the finding that profuse dye leakage from neovascular complexes obscured the view of the peripheral retina. If the five angiograms in which this occurred were excluded, oral angiography identified 23 of the 24 eyes in which significant nonperfusion was found on IVFFA.

CONCLUSION

Oral angiography with the SLO can provide high-quality angiograms that allow judgments to be made about the presence of treatable diabetic maculopathy, proliferative diabetic retinopathy, and peripheral nonperfusion. In the presence of coexisting macular oedema, it proved to be an unreliable technique with which to investigate foveal ischaemia.

Towards implementation of AI in New Zealand national diabetic screening program: Cloud-based, robust, and bespoke

Convolutional Neural Networks (CNNs) have become a prominent method of AI implementation in medical classification tasks. Grading Diabetic Retinopathy (DR) has been at the forefront of the development of AI for ophthalmology. However, major obstacles remain in the generalization of these CNNs onto real-world DR screening programs. We believe these difficulties are due to use of 1) small training datasets (<5,000 images), 2) private and 'curated' repositories, 3) locally implemented CNN implementation methods, while 4) relying on measured Area Under the Curve (AUC) as the sole measure of CNN performance. To address these issues, the public EyePACS Kaggle Diabetic Retinopathy dataset was uploaded onto Microsoft Azure™ cloud platform. Two CNNs were trained; 1 a "Quality Assurance", and 2. a "Classifier". The Diabetic Retinopathy classifier CNN (DRCNN) performance was then tested both on 'un-curated' as well as the 'curated' test set created by the "Quality Assessment" CNN model. Finally, the sensitivity of the DRCNNs was boosted using two post-training techniques. Our DRCNN proved to be robust, as its performance was similar on 'curated' and 'un-curated' test sets. The implementation of 'cascading thresholds' and 'max margin' techniques led to significant improvements in the DRCNN's sensitivity, while also enhancing the specificity of other grades.

Incidence, risk factors and outcomes of submacular haemorrhage with loss of vision in neovascular age-related macular degeneration in daily clinical practice: data from the FRB! registry

PURPOSE

The main purpose of the study was to report the estimated incidence, cumulative rate, risk factors and outcomes of submacular haemorrhage (SMH) with loss of vision in neovascular age-related macular degeneration (nAMD) receiving intravitreal injections (IVT) of vascular endothelial growth factor (VEGF) inhibitor in routine clinical practice.

METHODS

Retrospective analysis of treatment-naïve eyes receiving IVTs of VEGF inhibitors (ranibizumab, aflibercept or bevacizumab) for nAMD from 1 January 2010 to 31 December 2020 that were tracked the Fight Retinal Blindness! registry. Estimated incidence, cumulative rate and hazard ratios (HR) of SMH with loss of vision during treatment were measured using the Poisson regression, Kaplan-Meier survival curves and Cox proportional hazard models.

RESULTS

We identified 7642 eyes (6425 patients) with a total of 135 095 IVT over a 10-year period. One hundred five eyes developed SMH with loss of vision with a rate of 1 per 1283 injections (0.08% 95% confidence interval [95% CI] [0.06; 0.09]). The estimated incidence [95% CI] was 4.6 [3.8; 5.7] SMH with loss of vision per year per 1000 treated patients during the study. The cumulative [95% CI] rate of SMH per patient did not increase significantly with each successive injection (p = 0.947). SMH cases had a mean VA drop of around 6 lines at diagnosis, which then improved moderately to a 4-line loss at 1 year.

CONCLUSIONS

Submacular haemorrhage (SMH) with loss of vision is an uncommon complication that can occur at any time in eyes treated for nAMD in routine clinical practice, with only limited recovery of vision 1 year later.

Outcomes of cataract surgery in eyes with diabetic macular oedema: Data from the Fight Retinal Blindness! Registry

IMPORTANCE

There are limited data on real-world outcomes of cataract surgery in eyes receiving intravitreal treatments for diabetic macular oedema (DMO).

BACKGROUND

Cataract surgery may exacerbate oedema in some eyes with DMO resulting in inferior outcomes.

DESIGN

Matched, case-controlled retrospective study of observational data in routine clinical practice.

PARTICIPANTS

Eyes receiving intravitreal treatments for DMO tracked in the Fight Retinal Blindness! Registry.

METHODS

Eyes that underwent cataract surgery were identified and matched 1:1 with phakic controls also receiving intravitreal injections for DMO. We also assessed potential factors that were associated with better visual acuity (VA) outcomes.

MAIN OUTCOME MEASURES

Change in VA 6 months after cataract surgery.

RESULTS

Cataract surgery was identified in 208 eyes of 156 patients of which 147 eyes had 6 months of observations before and after surgery. The mean VA 6 months after surgery improved by 10.6 letters and was similar to their matched phakic controls (68.8 vs 69.2 letters; P = 0.8). Mean CST both 6 months before (341 μm) and after (360 μm) surgery were similar (P = 0.08). However, these eyes had thicker maculae and they received more injections than their matched phakic controls both before and after surgery. Eyes with worse VA before surgery and those that had received intravitreal treatment in the 4 weeks preceding surgery were more likely to gain vision.

CONCLUSIONS AND RELEVANCE

Visual outcomes of cataract surgery in eyes receiving intravitreal therapy for DMO were reasonably better. Their maculae were thicker and required more injections in the 6 months before and after surgery than their phakic controls.

Type 3 neovascularisation (retinal angiomatous proliferation) treated with antivascular endothelial growth factor: real-world outcomes at 24 months

Aims

To compare 24 months outcomes of eyes with retinal angiomatous proliferations (RAPs) treated with antivascular endothelial growth factor (anti-VEGF) with a group of controls diagnosed with other neovascular age-related macular degeneration (nAMD) subtypes in a real-world setting.

Methods

Treatment-naïve nAMD eyes that commenced anti-VEGF between January 2006 and November 2015 were identified from a registry of nAMD treatment outcomes. Cases were defined as eyes diagnosed with RAP. Three controls per case were selected among nAMD eyes with non-RAP lesions and matched on baseline visual acuity (VA), year of treatment initiation, anti-VEGF agent first injected and follow-up. Baseline VA was compared with 12 and 24 months VA. Change in VA, number of injections received, proportion of visits with active nAMD and time to first inactivation were compared between RAPs and controls.

Results

157 RAPs and 469 controls were included. Baseline VA (mean (SD)) increased at 12 months (61.4 (15.5) vs 68.7 (14.7) letters, p<0.001) and remained higher (66.6 (17.3) letters) at 24 months (p<0.001) in RAPs. The change from baseline VA (mean(95% CI)) was significantly higher in RAPs than in controls at 12 months (7.3 (5.4 to 9.1) vs 4.1 (2.8 to 5.4) letters, p=0.01) and at 24 months (5.1 (2.8 to 7.3) vs 2.5 (1 to 4) letters, p=0.056). Both groups received a median of 13 injections. RAPs inactivated earlier and were less active than controls (both p<0.001).

Conclusions

RAPs responded well to anti-VEGF, with a significant improvement in VA persisting at 24 months. RAPs had better visual outcomes than controls at 12 and 24 months, tended to inactivate earlier and were less active throughout 2 years follow-up.

Hyper-reflective dots in optical coherence tomography imaging and inflammation markers in diabetic retinopathy

The aim of this study is to correlate small dot hyper-reflective foci (HRF) observed in spectral domain optical coherence tomography (SD-OCT) scans of an animal model of hyperglycaemia with focal electroretinography (fERG) response and immunolabelling of retinal markers. The eyes of an animal model of hyperglycaemia showing signs of diabetic retinopathy (DR) were imaged using SD-OCT. Areas showing dot HRF were further evaluated using fERG. Retinal areas enclosing the HRF were dissected and serially sectioned, stained and labelled for glial fibrillary acidic protein (GFAP) and a microglial marker (Iba-1). Small dot HRF were frequently seen in OCT scans in all retinal quadrants in the inner nuclear layer or outer nuclear layer in the DR rat model. Retinal function in the HRF and adjacent areas was reduced compared with normal control rats. Microglial activation was detected by Iba-1 labelling and retinal stress identified by GFAP expression in Müller cells observed in discrete areas around small dot HRF. Small dot HRF seen in OCT images of the retina are associated with a local microglial response. This study provides the first evidence of dot HRF correlating with microglial activation, which may allow clinicians to better evaluate the microglia-mediated inflammatory component of progressive diseases showing HRF.

Retinal pigment epithelial changes and choroidal neovascularisation at the edge of posterior staphylomas; a case series and review of the literature

PURPOSE

To report five myopic patients who presented with a variety of changes at the edge of posterior staphyloma.

METHODS

Retrospective, observational case series. The clinical and angiographic records of five patients who showed changes at the edge of posterior staphyloma were reviewed. One of these patients had been referred querying macular dystrophy.

RESULTS

On fundus examination, three patients showed retinal pigment epithelial (RPE) changes at the edge of the staphyloma and two showed RPE atrophy with surrounding haemorrhages. Fluorescein angiography revealed areas of hyperfluorescence at the point of change of curvature of the staphyloma suggestive of RPE atrophy in all patients. In two patients, a choroidal neovascular membrane was seen. Indocyanine green angiogram carried out in one patient showed the presence of an occult choroidal neovascular membrane with preservation of the adjacent choriocapillaris.

CONCLUSION

This case series illustrates the variety of changes that can occur at the edge of posterior staphylomas, which ranged from RPE disturbance to choroidal neovascular membrane formation. In one of the patients, these changes were mistaken for macular dystrophy. Our observations also support the hypothesis that chorioretinal changes occur at the edge of staphylomas and may predispose to choroidal neovasularisation.

Evaluation of the prevalence of non-diabetic eye disease detected at first screen from a single region diabetic retinopathy screening program: a cross-sectional cohort study in Auckland, New Zealand

OBJECTIVES

To evaluate the prevalence of incidental non-diabetic ocular comorbidities detected at first screen in a large diabetic retinopathy (DR) screening programme.

DESIGN

Cross-sectional cohort study.

SETTING

Single large metropolitan diabetic eye screening programme in Auckland, New Zealand.

PARTICIPANTS

Twenty-two thousand seven hundred and seventy-one participants who attended screening from September 2008 to August 2018.

RESULTS

Hypertensive retinopathy (HTR) was observed in 14.2% (3236/22 771) participants. Drusen were present in 14.0% participants under the age of 55 years, increasing to 20.5% in those 55 years and older. The prevalence of neovascular age-related macular degeneration (AMD) was 0.5% in participants aged<55 years, 2.4% in participants aged 55-75 years and 16% in participants aged>75 years. Retinal vein occlusion and retinal arterial embolus were prevalent in 0.7% and 0.02%, respectively, in participants aged<55 years, increasing to 2.2% and 0.4%, respectively, in those >75 years. Cataracts were common being present in 37.1% of participants over the age of 75 years. Only 386 individuals (1.7%) were labelled as glaucoma suspects. Geographic atrophy, epiretinal membrane, choroidal nevi and posterior capsular opacification had an increased prevalence in older individuals.

CONCLUSIONS

Our data suggest that AMD, HTR and cataracts are routinely detected during DR screening. The incorporation of the detection of these ocular comorbidities during DR screening provide opportunities for patients to modify risk factors (smoking cessation and diet for AMD, blood pressure for HTR) and allow access to cataract surgery.

Application of Arterial Spin Labelling in Detecting Retinal Ischemia

Purpose

Here, we have tried to quantify the chorioretinal blood perfusion in patients who are clinically identified to be suffering from retinal ischemia using arterial spin labelling (ASL) MRI.

Method

Four participants, diagnosed with retinal ischemia based on their structural OCT and angiography test, were then scanned using anatomical MRI as well as ASL. We optimized MR parameters to maximize resolution and target fixation, blinking, and breathing ques to minimize motion artifacts.

Results

Participants had a maximum of ∼50 mL/100 mL/min of blood perfusion, which is below the normal values of ∼200 mL/100 mL/min. It also appeared that thinning of the choroid contributes more to the measured decreased chorioretinal perfusion, compared to slowed arterial filling time.

Conclusion

Decreased chorioretinal perfusion is a multifactorial event and has been implicated in several posterior eye pathologies. Based on our current results, it seems that ischemia of the eye could be due to anatomy (tissue volume) and/or functionality (arterial flow).

Quantification of Optical Coherence Tomography Angiography in Age and Age-Related Macular Degeneration Using Vessel Density Analysis

PURPOSE

The aim of this study was to determine whether vessel density (VD) as measured by optical coherence tomography (OCT) angiography provided insights into retinal and choriocapillaris vascular changes with aging and intermediate dry age-related macular degeneration (AMD).

DESIGN

Non-randomized observational study.

METHODS

Seventy-five participants were recruited into 3 cohorts: young healthy group, old healthy, and those at high-risk for exudative AMD. Raw OCT and OCT angiography data from TOPCON DRI OCT Triton were exported using Topcon IMAGENET 6.0 software, and 3D datasets were analysed to determine retinal thickness and VD.

RESULTS

Central macular thickness measurements revealed a trend of overall retinal thinning with increasing age. VD through the full thickness of the retina was highest in Early Treatment Diabetic Retinopathy Study (ETDRS) sector 4 (the inferior macula) in all the cohorts. Mean VD was significantly higher in the deep capillary plexus than the superficial capillary plexus in all ETDRS sectors in all cohorts, but there was no significant difference noted between groups. Choriocapillaris VD was significantly lower in all ETDRS sectors in the AMD group compared with the young healthy and the old healthy groups.

CONCLUSIONS

Retinal VD maps, derived from the retinal plexi, are not reliable biomarkers for assessing the aging macular. Our nonproprietary analysis of the vascular density of the choriocapillaris revealed a significant drop off of VD with age and disease, but further work is required to corroborate this finding. If repeatable, choriocapillaris VD may provide a noninvasive biomarker of healthy aging and disease.

THEIA™ development, and testing of artificial intelligence-based primary triage of diabetic retinopathy screening images in New Zealand

AIM

To develop and evaluate an artificial intelligence triage system with high sensitivity for detecting referable diabetic retinopathy and maculopathy, while maintaining high specificity for non-referable disease, for clinical implementation within the New Zealand national diabetic retinopathy screening programme.

METHODS

The THEIA™ artificial intelligence system for retinopathy and maculopathy screening, was developed at Toku Eyes using routinely collected retinal screening datasets from two of the largest district health boards in Auckland, New Zealand: the Auckland District Health Board and the Counties Manukau District Health Board. All retinal images from consecutive individuals receiving retinal screening between January 2009 and December 2018 were used. Images were labelled as non-sight-threatening, potentially referable or sight-threatening for New Zealand implementation, or as referable (potentially referable + sight-threatening)/non-referable (non-sight-threatening) for global comparison.

RESULTS

Data from 32 354 unique people with diabetes (63 843 when including multiple visits) were available, of which 95-97%, 0.9-2.4% and 1.1-3.1% were categorized as non-sight-threatening, potentially referable and sight-threatening, respectively. Using the referable/non-referable categories, THEIA achieved overall sensitivity of 94% (95% CI 92-95) in the Auckland District Health Board and 95% (95% CI 92-97) in the Counties Manukau District Health Board datasets, while preserving specificity of 63% (95% CI 62-64) for the Auckland District Health Board and 61% (95% CI 60-62) for the Counties Manukau District Health Board. Implementing THEIA into a New Zealand national diabetic screening programme could significantly reduce the manual grading load.

CONCLUSION

THEIA, an artificial intelligence tool to assist in clinical decision-making, tailored to the needs of the New Zealand national diabetic screening programme, delivered high sensitivity for detecting referable retinopathy within the multi-ethnic New Zealand population with diabetes.

Combined strabismus and phacoemulsification cataract surgery: a useful option in selected patients

PURPOSE

To evaluate the role of combined strabismus and phacoemulsification cataract extraction in patients with symptomatic cataract and strabismus.

METHODS

Four procedures of combined strabismus and cataract surgery are described in 3 elderly patients with strabismus of differing aetiologies. Two patients underwent one procedure; the other patient underwent two combined procedures, one to each eye.

RESULTS

The visual acuity improved in all 3 patients. Post-operative alignment of the visual axis was achieved which allowed resolution of symptomatic diplopia in patient 1, functional binocular single vision in patient 2 and a noticeably reduced compensatory head posture in patient 3.

CONCLUSIONS

Combined strabismus and cataract surgery is a safe procedure that can optimise visual alignment and improve visual acuity with a minimum number of operations.

Use of public sector diabetes eye services in New Zealand 2006-2019: Analysis of national routinely collected datasets

OBJECTIVE

To assess diabetes eye service use in New Zealand among people aged ≥15 years by estimating service attendance, biennial screening rate, and disparities in the use of screening and treatment services.

METHODS

We obtained Ministry of Health data from the National Non-Admitted Patient Collection on diabetes eye service events between 1 July 2006 and 31 December 2019 and sociodemographic and mortality data from the Virtual Diabetes Register and linked these using a unique patient identifier (encrypted National Health Index). We 1) summarized attendance at retinal screening and ophthalmology services, 2) calculated biennial and triennial screening rate, 3) summarized treatment with laser and anti-VEGF and used log-binomial regression to examine associations of all of these with age group, ethnicity, and area-level deprivation.

RESULTS

In total, 245,844 people aged ≥15 years had at least one diabetes eye service appointment attended or scheduled; half of these (n = 125,821, 51.2%) attended only retinal screening, one-sixth attended only ophthalmology (n = 35,883, 14.6%) and one-third attended both (n = 78,300, 31.8%). The biennial retinal screening rate was 62.1%, with large regional variation (73.9% in Southern District to 29.2% in West Coast). Compared with NZ Europeans, Māori were approximately twice as likely to never receive diabetes eye care or to access ophthalmology when referred from retinal screening, 9% relatively less likely to receive biennial screening and received the fewest anti-VEGF injections when treatment was commenced. Disparities in service access were also present for Pacific Peoples compared to NZ Europeans, younger and older age groups compared to those aged 50-59 years and those living in areas with higher deprivation.

CONCLUSIONS

Access to diabetes eye care is suboptimal, with substantial disparity between age groups, ethnicity groups, area level deprivation quintile and across districts. Efforts to improve access to and quality of diabetes eye care services must include strengthening data collection and monitoring.

Development and validation of a deep-learning model to predict 10-year atherosclerotic cardiovascular disease risk from retinal images using the UK Biobank and EyePACS 10K datasets

Background

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of death globally, and early detection of high-risk individuals is essential for initiating timely interventions. The authors aimed to develop and validate a deep learning (DL) model to predict an individual's elevated 10-year ASCVD risk score based on retinal images and limited demographic data.

Methods

The study used 89,894 retinal fundus images from 44,176 UK Biobank participants (96% non-Hispanic White, 5% diabetic) to train and test the DL model. The DL model was developed using retinal images plus age, race/ethnicity, and sex at birth to predict an individual's 10-year ASCVD risk score using the pooled cohort equation (PCE) as the ground truth. This model was then tested on the US EyePACS 10K dataset (5.8% non-Hispanic White, 99.9% diabetic), composed of 18,900 images from 8969 diabetic individuals. Elevated ASCVD risk was defined as a PCE score of ≥7.5%.

Results

In the UK Biobank internal validation dataset, the DL model achieved an area under the receiver operating characteristic curve of 0.89, sensitivity 84%, and specificity 90%, for detecting individuals with elevated ASCVD risk scores. In the EyePACS 10K and with the addition of a regression-derived diabetes modifier, it achieved sensitivity 94%, specificity 72%, mean error -0.2%, and mean absolute error 3.1%.

Conclusion

This study demonstrates that DL models using retinal images can provide an additional approach to estimating ASCVD risk, as well as the value of applying DL models to different external datasets and opportunities about ASCVD risk assessment in patients living with diabetes.