Impact of treat and extend criteria on proportions that can be extended after loading phase of 2 mg aflibercept therapy for neovascular age related macular degeneration: PRECISE Report 5.

OBJECTIVE: To study the impact of definitions of various treatment extension criteria on the proportion of patients who could be extended at their first visit after the loading phase of 2 mg aflibercept therapy for neovascular age related macular degeneration (nAMD). METHODS: Patients with nAMD initiated on the loading phase of three intravitreal doses of 2 mg aflibercept in routine clinical practice were recruited from December 2019 to August 2021. The response to the loading phase was assessed at approximately 8 weeks post-loading (up to 140 days from first injection) based on different definitions of response. The proportion of patients that qualify for interval extension based on different clinical trial criteria was also evaluated. RESULTS: A total of 722 patients with visual acuity (VA) and optical coherence tomography (OCT) scans done at all 4 visits were included. Of these 32.4% of eyes responded with complete macular fluid resolution after the first injection with no recurrence through the loading phase (super-responders) while 26.9% had persistent macular fluid in all 4 visits (true non-responders). The rest were considered suboptimal responders. Change in VA showed marked variations within each of these categories of fluid resolution. For extension of next treatment interval, if presence of any macular fluid at the post-loading visit is the only criteria considered, about 50% could be extended to 8 weeks. If both VA worsening by ≥5 letters and a > 25 µm increase in central sub-field thickness (CST) are considered, 90% will be eligible for interval extension. CONCLUSION: Clinical trial designs and pre-defined treatment extension/shortening criteria determine the proportion of patients requiring treatment in the post-loading visit. The short and long-term impact of interval extension immediate post-loading on visual outcome in clinical practice is unknown.

A Multi-Modal AI-Driven Cohort Selection Tool to Predict Suboptimal Non-Responders to Aflibercept Loading-Phase for Neovascular Age-Related Macular Degeneration: PRECISE Study Report 1.

Patients diagnosed with exudative neovascular age-related macular degeneration are commonly treated with anti-vascular endothelial growth factor (anti-VEGF) agents. However, response to treatment is heterogeneous, without a clinical explanation. Predicting suboptimal response at baseline will enable more efficient clinical trial designs for novel, future interventions and facilitate individualised therapies. In this multicentre study, we trained a multi-modal artificial intelligence (AI) system to identify suboptimal responders to the loading-phase of the anti-VEGF agent aflibercept from baseline characteristics. We collected clinical features and optical coherence tomography scans from 1720 eyes of 1612 patients between 2019 and 2021. We evaluated our AI system as a patient selection method by emulating hypothetical clinical trials of different sizes based on our test set. Our method detected up to 57.6% more suboptimal responders than random selection, and up to 24.2% more than any alternative selection criteria tested. Applying this method to the entry process of candidates into randomised controlled trials may contribute to the success of such trials and further inform personalised care.

Multicenter Evaluation of Diagnostic Circulating Biomarkers to Detect Sight-Threatening Diabetic Retinopathy.

Importance: It is a global challenge to provide regular retinal screening for all people with diabetes to detect sight-threatening diabetic retinopathy (STDR). Objective: To determine if circulating biomarkers could be used to prioritize people with type 2 diabetes for retinal screening to detect STDR. Design, Setting, and Participants: This cross-sectional study collected data from October 22, 2018, to December 31, 2021. All laboratory staff were masked to the clinical diagnosis, assigned a study cohort, and provided with the database containing the clinical data. This was a multicenter study conducted in parallel in 3 outpatient ophthalmology clinics in the UK and 2 centers in India. Adults 40 years and older were categorized into 4 groups: (1) no history of diabetes, (2) type 2 diabetes of at least 5 years' duration with no evidence of DR, (3) nonproliferative DR with diabetic macular edema (DME), or (4) proliferative DR. STDR comprised groups 3 and 4. Exposures: Thirteen previously verified biomarkers were measured using enzyme-linked immunosorbent assay. Main Outcomes and Measures: Severity of DR and presence of DME were diagnosed using fundus photographs and optical coherence tomography. Weighted logistic regression and receiver operating characteristic curve analysis (ROC) were performed to identify biomarkers that discriminate STDR from no DR beyond the standard clinical parameters of age, disease duration, ethnicity (in the UK) and hemoglobin A1c. Results: A total of 538 participants (mean [SD] age, 60.8 [9.8] years; 319 men [59.3%]) were recruited into the study. A total of 264 participants (49.1%) were from India (group 1, 54 [20.5%]; group 2, 53 [20.1%]; group 3, 52 [19.7%]; group 4, 105 [39.8%]), and 274 participants (50.9%) were from the UK (group 1, 50 [18.2%]; group 2, 70 [25.5%]; group 3, 55 [20.1%]; group 4, 99 [36.1%]). ROC analysis (no DR vs STDR) showed that in addition to age, disease duration, ethnicity (in the UK) and hemoglobin A1c, inclusion of cystatin C had near-acceptable discrimination power in both countries (area under the receiver operating characteristic curve [AUC], 0.779; 95% CI, 0.700-0.857 in 215 patients in the UK with complete data; AUC, 0.696; 95% CI, 0.602-0.791 in 208 patients in India with complete data). Conclusions and Relevance: Results of this cross-sectional study suggest that serum cystatin C had good discrimination power in the UK and India. Circulating cystatin-C levels may be considered as a test to identify those who require prioritization for retinal screening for STDR.

AMP-activated protein kinase is a key regulator of acute neurovascular permeability.

Many neuronal and retinal disorders are associated with pathological hyperpermeability of the microvasculature. We have used explants of rodent retinae to study acute neurovascular permeability, signal transduction and the role of AMP-activated protein kinase (AMPK). Following stimulation with either vascular endothelial growth factor (VEGF-A) or bradykinin (BK), AMPK was rapidly and strongly phosphorylated and acted as a key mediator of permeability downstream of Ca2+. Accordingly, AMPK agonists potently induced acute retinal vascular leakage. AMPK activation led to phosphorylation of endothelial nitric oxide synthase (eNOS, also known as NOS3), which in turn increased VE-cadherin (CDH5) phosphorylation on Y685. In parallel, AMPK also mediated phosphorylation of p38 MAP kinases (hereafter p38) and HSP27 (HSPB1), indicating that it regulated paracellular junctions and cellular contractility, both previously associated with endothelial permeability. Endothelial AMPK provided a missing link in neurovascular permeability, connecting Ca2+ transients to the activation of eNOS and p38, irrespective of the permeability-inducing factor used. Collectively, we find that, due to its compatibility with small molecule antagonists and agonists, as well as siRNA, the ex vivo retina model constitutes a reliable tool to identify and study regulators and mechanisms of acute neurovascular permeability.

Low Luminance Visual Acuity and Low Luminance Deficit in Proliferative Diabetic Retinopathy.

This study aimed to determine the relation of best corrected visual acuity (BCVA) and low luminance visual acuity (LLVA) in proliferative diabetic retinopathy (PDR) following treatment with either aflibercept or pan-retinal photocoagulation (PRP). The study was conducted as a post-hoc analysis of the CLARITY trial in which naïve and PRP treated PDR patients were randomised to receive either aflibercept or PRP. BCVA and LLVA were assessed at baseline and at week 52. Our analyses showed that the BCVA and LLVA correlate well in treatment naïve PDR with an average low luminance deficit of 11.79 Early Treatment Diabetic Retinopathy Score (ETDRS) letters. However, LLVA at lower levels of BCVA showed more variance. Post aflibercept therapy, the mean change in BCVA and LLVA at 52 weeks after aflibercept was +2.1 (SD 6.05) letters and +0.39 (SD 5.6) letters, respectively. Similarly, after PRP, it was -2.5 (SD 4.9) letters and -1.9 (SD 8.7) letters, respectively. When comparing treatment arms, BCVA change was found to be statistically significant (p < 0.001) whereas LLVA was not (p = 0.11). These findings show that LLVA does not respond as well as BCVA following any treatment for PDR, even though BCVA and LLVA both test foveal function.

Outcomes Associated With Sustained-Release Intraocular Fluocinolone Implants in a Case of Melanoma-Associated Retinopathy Treated Without Systemic Immunosuppression.

Importance: Melanoma-associated retinopathy (MAR) is a paraneoplastic syndrome in which antiretinal antibodies crossreact with retinal ON-bipolar cells, resulting in night blindness and progressive visual field loss. Current therapeutic options include cytoreductive surgery in combination with immunoglobulin, corticosteroids, or plasmapheresis, but their effectiveness is limited and may be contraindicated, given the possible protective role of circulating autoantibodies against metastatic spread. We report 3-year follow-up of the first case (to our knowledge) of MAR treated with intravitreal long-acting steroid implants. Objective: To report on a patient with MAR who was treated with intravitreal fluocinolone acetonide implants in the absence of systemic immunosuppression. Design, Setting, and Participants: This is a 3-year follow-up of a 73-year-old woman with a history of surgical excision of a malignant melanoma of the left pinna who presented with visual symptoms of shimmering and nyctalopia. Fundus examination, fundus autofluorescence, and optical coherence tomography were normal, with no evidence of cystoid macular edema. Automated perimetry showed a reduction in visual field and full-field electroretinography (ERG) demonstrated findings consistent with generalized ON-bipolar cell dysfunction, typical of MAR. The patient was treated with bilateral fluocinolone acetonide intravitreal implants. Main Outcomes and Measures: Visual acuity, visual field, and electroretinography testing for 3 years after treatment. Results: Visual fields improved in this 73-year-old patient from 20/30 (Snellen measured as 6/9) OD and 20/16 (6/5) OS at baseline to 20/20 OU within 1 week of treatment. Detailed electroretinography monitoring indicated characteristic abnormalities that partly resolved after treatment, consistent with improved inner retinal ON-bipolar cell function. Bilateral cataracts developed approximately 2 years after injection; cataract surgery was performed uneventfully. At 3 years posttreatment, the patient remained visually stable and in systemic disease remission, with best-corrected visual acuity remaining at 20/20 OU. Conclusions and Relevance: We report what is, to our knowledge, the first case of MAR treated with intravitreal slow-release corticosteroid implants, which shows improvements in visual symptoms, visual fields, and retinal function. Sustained-release intraocular steroid implants may offer an effective and safe alternative to systemic immunosuppression in MAR, although results from 1 case should be generalized with abundant caution.

NHS litigation in bariatric surgery over a ten year period.

Negligence claims in the UK NHS has increased over the last 30 years. The aim of this present study was determine the number of claims and the cost of litigation in Bariatric Surgery and compare it to similar other specialties. Data was received from NHS Litigation Authority (NHSLA) in response to Freedom of Information data request. There was a total of 7 claims, of which 4 were successful. The total pay out sum was £210,000 in 10 years. This is a very low amount compared to other surgical specialties. This low level of litigation probably indicates that the current bariatric surgical services in the NHS are delivering safe care with good patient satisfaction. This needs to be carefully considered prior to changing the payment tariffs for bariatric surgery.