Time to glaucoma progression detection by optical coherence tomography and visual field in glaucoma individuals of African descent.

PURPOSE: To examine the time to glaucoma progression detection by retinal nerve fiber layer thickness (RNFLT) and visual field (VF) among African descent (AD) individuals. DESIGN: Retrospective cohort study. METHODS: Setting: Multi-center. STUDY POPULATION: We included AD glaucoma eyes from DIGS/ADAGES with ≥2-year/5-visits of optic nerve head RNFLT and 24-2 VF examinations. Intervention or Observation Procedure: Rates of VF mean deviation (MD) and RNFLT worsening were analyzed using linear mixed-effects models, and longitudinal data was simulated using the variability estimates. MAIN OUTCOME MEASURE: The simulated time to detect trend-based glaucoma progression was assessed with assumed rates of VF MD and RNFLT change derived from the cohort (25th, 50th, 75th percentile [p25, median, p75] slopes and mean slopes). Severity-stratified analyses were also performed. RESULTS: We included 184 eyes from 128 AD subjects (mean baseline age: 63.4 years; VF MD: -4.2 dB, RNFLT: 80.2 µm). The p25, median, mean and p75 rates of change were -0.43, -1.01, -1.15 and -1.64 µm/year for RNFLT, and 0.00, -0.21, -0.30 and -0.51 dB/year for VF MD, respectively. Compared to VF MD, RNFLT showed an overall shorter mean time to progression detection (time difference: 0.4-1.7 years), with the mean rates showing the largest difference (RNFLT: 5.2 years vs. VF MD: 6.9 years). Similarly, we found an overall shorter time to detect RNFLT progression, compared to that of VF MD progression, in mild glaucoma eyes (≥1 year earlier) and in moderate-advanced glaucoma eyes (∼0.5 year earlier). CONCLUSIONS: Computer simulation showed potentially shorter time to detect RNFLT progression than VF MD progression in AD eyes. Our findings support the importance of using RNFLT to detect progressive glaucoma in AD individuals.

Corneal Epithelial Thickness in Sjogren's Disease: A Pilot Study.

Purpose: This study was to assess corneal epithelial thickness (CET) in patients with Sjogren's disease (SjD). Methods: A retrospective chart review was conducted of SjD patients from September 2021 to January 2022. Patient demographics, unanesthetized Schirmer's test, serologic markers, and symptoms as measured by the Ocular Surface Disease Index (OSDI) were reviewed. Epithelial thickness from both eyes was measured using anterior segment OCT at the central 3mm and concentric 5mm, 7mm, and 9mm zones for the superior, temporal, inferior, and nasal corneal quadrants. Associations between corneal epithelial thickness with patient demographics, clinical characteristics, and symptoms were evaluated using regression models. Results: Fifteen SjD patients (100% female) were included with a mean age of 58.4 years. Patients with Sjogren's disease had a significantly thinner superior corneal epithelium compared to the inferior epithelium (mean 47.7mm vs 53.1mm, p = 0.001). The epithelial thickness mean standard deviation (MSD) was significantly inversely correlated with the unanesthetized Schirmer test (r=-0.39, p = 0.005), suggesting that an overall variability of CET correlates with decreased aqueous tear production. SS-A, SS-B, ANA, and RF positivity were not associated with any measures of CET. Conclusion: This pilot study suggests that there is significant superior versus inferior thinning of corneal epithelium in Sjogren's patients. There was a significant correlation between variability of corneal epithelial thickness and decreased tear production in Sjogren's patients. Further larger studies are needed to understand the relationship of CET with objective and subjective measurements of ocular surface disease.

Retinal layer thinning for monitoring disease-modifying treatment in relapsing multiple sclerosis-Evidence for applying a rebaselining concept.

BACKGROUND: Employing a rebaselining concept may reduce noise in retinal layer thinning measured by optical coherence tomography (OCT). METHODS: From an ongoing prospective observational study, we included patients with relapsing multiple sclerosis (RMS), who had OCT scans at disease-modifying treatment (DMT) start (baseline), 6-12 months after baseline (rebaseline), and ⩾12 months after rebaseline. Mean annualized percent loss (aL) rates (%/year) were calculated both from baseline and rebaseline for peripapillary-retinal-nerve-fiber-layer (aLpRNFLbaseline/aLpRNFLrebaseline) and macular-ganglion-cell-plus-inner-plexiform-layer (aLGCIPLbaseline/aLGCIPLrebaseline) by mixed-effects linear regression models. RESULTS: We included 173 RMS patients (mean age 31.7 years (SD 8.8), 72.8% female, median disease duration 15 months (12-94) median baseline-to-last-follow-up-interval 37 months (18-71); 56.6% moderately effective DMT (M-DMT), 43.4% highly effective DMT (HE-DMT)). Both mean aLpRNFLbaseline and aLGCIPLbaseline significantly increased in association with relapse (0.51% and 0.26% per relapse, p < 0.001, respectively) and disability worsening (1.10% and 0.48%, p < 0.001, respectively) before baseline, but not with DMT class. Contrarily, neither aLpRNFLrebaseline nor aLGCIPLrebaseline was dependent on relapse or disability worsening before baseline, while HE-DMT significantly lowered aLpRNFLrebaseline (by 0.31%, p < 0.001) and aLGCIPLrebaseline (0.25%, p < 0.001) compared with M-DMT. CONCLUSIONS: Applying a rebaselining concept significantly improves differentiation of DMT effects on retinal layer thinning by avoiding carry-over confounding from previous disease activity.

Line-field confocal optical coherence tomography: Characteristic hints for the diagnosis of scarring alopecia due to lupus erythematodes: A preliminary study.

INTRODUCTION: Lupus erythematosus (LE) is an inflammatory autoimmune disease, that can affect the skin to varying degree. In particular, discoid LE (DLE) and the rare form of lupus panniculitis/profundus are associated with scarring alopecia. The heterogeneity of the clinical, dermatoscopic, and histologic presentation poses a major challenge to the clinician in the diagnosis and differential diagnosis of other forms of scarring alopecia. OBJECTIVE: While noninvasive imaging techniques using optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) have proven to be helpful in the diagnosis of scarring alopecia in the context of LE, this study aimed to investigate line-field confocal OCT (LC-OCT) to identify characteristic features of cicatricial alopecia in LE. METHODS: Fifteen patients with cicatricial alopecia in LE were included and the most affected/inflamed areas of the scalp were prospectively examined. In analogy to histopathology and previously reported criteria in RCM, all images were evaluated according to seven established criteria and underwent descriptive analyses. RESULTS: LC-OCT revealed characteristic features of cicatricial alopecia, such as lymphocytic interface dermatitis (14/15; 93.3%) and basal cell vacuolization (13/15; 86.7%). The most impressive feature was the occurrence of prominent hyperreflective fibers in 14/15 patients (93.3%). CONCLUSION: LC-OCT imaging can noninvasively detect morphologic criteria such as lymphocytic and vacuolar interface dermatitis of cicatricial alopecia due to LE. In particular, the presence of hyperreflective collagen fibers appears to be a characteristic easily recognizable feature that may facilitate differential diagnosis with other forms of cicatricial alopecia. Further studies are mandatory to differentiate other forms of scarring alopecia.

Characterization and protein engineering of a novel UDP-glycosyltransferase involved in pseudoginsenoside Rt5 biosynthesis from Panax japonicus.

As one of rare high-value ocotillol (OCT)-type ginsenosides, pseudoginsenoside Rt5 has been identified with significant pharmacological activities. UDP-glycosyltransferases (UGTs) play pivotal roles in catalyzing the transfer of a glycosyl moiety from a donor to an acceptor. In this study, the novel UGT, PjUGT10, was screened from the transcriptome database of Panax japonicus and identified with the enzymatic activity of transferring a glucosyl group on OCT to produce Rt5. The catalytic efficiency of PjUGT10 was further enhanced by employing site-directed mutation. Notably, the variant M7 exhibited a remarkable 6.16 × 103-fold increase in kcat/Km towards 20S,24R-ocotillol and a significant 2.02 × 103-fold increase to UDP-glucose, respectively. Moreover, molecular dynamics simulations illustrated a reduced distance between 20S,24R-ocotillol and the catalytic residue His15 or UDP-glucose, favoring conformation interactions between the enzyme and substrates. Subsequently, Rt5 was synthesized in an engineered Escherichia coli strain M7 coupled with a UDP-glucose synthetic system. This study not only shed light on the protein engineering that can enhance the catalytic activity of PjUGT10, but also established a whole-cell approach for the production of Rt5.

Exploring Publicly Accessible Optical Coherence Tomography Datasets: A Comprehensive Overview.

Artificial intelligence has transformed medical diagnostic capabilities, particularly through medical image analysis. AI algorithms perform well in detecting abnormalities with a strong performance, enabling computer-aided diagnosis by analyzing the extensive amounts of patient data. The data serve as a foundation upon which algorithms learn and make predictions. Thus, the importance of data cannot be underestimated, and clinically corresponding datasets are required. Many researchers face a lack of medical data due to limited access, privacy concerns, or the absence of available annotations. One of the most widely used diagnostic tools in ophthalmology is Optical Coherence Tomography (OCT). Addressing the data availability issue is crucial for enhancing AI applications in the field of OCT diagnostics. This review aims to provide a comprehensive analysis of all publicly accessible retinal OCT datasets. Our main objective is to compile a list of OCT datasets and their properties, which can serve as an accessible reference, facilitating data curation for medical image analysis tasks. For this review, we searched through the Zenodo repository, Mendeley Data repository, MEDLINE database, and Google Dataset search engine. We systematically evaluated all the identified datasets and found 23 open-access datasets containing OCT images, which significantly vary in terms of size, scope, and ground-truth labels. Our findings indicate the need for improvement in data-sharing practices and standardized documentation. Enhancing the availability and quality of OCT datasets will support the development of AI algorithms and ultimately improve diagnostic capabilities in ophthalmology. By providing a comprehensive list of accessible OCT datasets, this review aims to facilitate better utilization and development of AI in medical image analysis.

Risk Factors for Focal Choroidal Excavation Concurrent with Chorioretinal Disease: Evaluated by Spectral-Domain OCT.

Purpose: To investigate the risk factors for patients with focal choroidal excavation (FCE) and their correlation with chorioretinal diseases. Design: Retrospective cross-sectional study. Subjects: Patients with FCE were enrolled, while healthy subjects were recruited for the control group. Methods: The study collected demographic information, clinical features, and multimodal images. Parameters of FCE identified using spectral-domain OCT (SD-OCT) were manually measured using built-in software and subsequently analyzed statistically. Main Outcome Measures: Subfoveal choroidal thickness (SFCT), subexcavation choroidal thickness (SECT), and the greatest depth and width of each excavation were manually measured using built-in calipers in OCT software. Results: Twenty-one patients (13/8, male/female) with FCE were included in this study. The average age was 45.2 years, and their best-corrected visual acuity (BCVA) was 0.4 logarithm of the minimum angle of resolution (Snellen equivalent, 20/50). Focal choroidal excavation was present in 28 eyes of 21 patients, including isolated FCE (12 eyes) and complicated FCE (16 eyes) with choroidal neovascularization (sCNV), central serous chorioretinopathy, and other conditions. Patients with complicated FCE were significantly older than those isolated FCE (P = 0.015). The SFCT of the healthy subjects was significantly less than that of the fellow eyes of the patients with FCE (P < 0.01), as was that of the eyes with isolated FCE (P < 0.001) and complicated FCE (P < 0.001). The width of excavation was wider in eyes with complicated FCE than in those with isolated FCE (P = 0.001). Hypertransmission defect (HD) was found beneath 15 excavations and was more prevalent in the complicated FCE group than the isolated FCE group (P = 0.023). Conclusions: Focal choroidal excavation appears to be closely related to chorioretinal disorders, and the width of the excavation is a significant indicator for evaluating the risk of chorioretinal diseases. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Author Reply to Letter to the Editor: In Response to: Comment on Fonollosa et al.'s "Hyper-Reflective Outer Nuclear Layer (HONL) in Vogt-Koyanagi-Harada Disease and Sympathetic Ophthalmia".

We have recently described an OCT sign in two patients (one with Vogt-Koyanagi-Harada (VKH) and the other with Sympathetic Ophthalmia) consisting of hyperreflectivity of the outer nuclear layer (HONL) that subsequently evolved into outer retina atrophy and associated with poor functional outcomes. Ali et al. have published a comment on our letter regarding HONL. They have evaluated it in 90 eyes of VKH patients. It was observed in 37 eyes (41.1%) and no associations were found between HONL and structural outcomes or final visual acuity, and no cases of retinal atrophy were described. In the present author's reply, we point out two reasons for these contradictory observations. First, we considered HONL a full thickness hyperreflectivity of the outer nuclear layer, whereas they included cases with partial thickness hyperreflectivity, hence probably milder cases. Second: they have assessed visual function by means of visual acuity, so cases with extrafoveal involvement whose functional deficiency might only be measured by other tests (i.e. visual field) might have been missed.

[Endocoronary imaging contribution in iatrogenic dissection management]. / Apport de l'imagerie endocoronaire dans la prise en charge d'une dissection iatrogène.

Iatrogenic coronary dissections are rare but potentially serious. Their management is complex, particularly if the dissection occurs without an angioplasty guide in the arterial lumen. In this context, angiography alone is insufficient, and endocoronary imaging is essential (using optical coherence or IVUS) to guide angioplasty when necessary (guide in the true lumen, coverage of the tear). We report here the case of an iatrogenic dissection of the right coronary artery treated with OFDI guiding.

Cross-sectional Analysis of Outer Retinal Tubulation in Inherited Retinal Diseases: A Multicenter Study.

PURPOSE: This study aims to explore genetic variants that potentially lead to outer retinal tubulation (ORT), estimate the prevalence of ORT in these candidate genes, and investigate the clinical etiology of ORT in patients with inherited retinal diseases (IRDs), with respect to each gene. DESIGN: Retrospective cohort study. METHODS: A retrospective cross-sectional review was conducted on 565 patients with molecular diagnoses of IRD, confirming the presence of ORT as noted in each patient's respective spectral-domain optical coherence tomography (SD-OCT) imaging. Using SD-OCT imaging, the presence of ORT was analyzed in relation to specific genetic variants and phenotypic characteristics. Outcomes included the observed ORT frequencies across two gene-specific cohorts: non- retinal pigment epithelium (RPE)-specific genes, and RPE-specific genes; and to investigate the analogous characteristics caused by variants in these genes. RESULTS: Among the 565 patients included in this study, 104 exhibited ORT on SD-OCT. We observed ORT frequencies among the following genes from our patient cohort: 100% (23/23) forCHM, 100%(2/2) forPNPLA6, 100% (4/4) forRCBTB1, 100% formtDNA[100% (4/4) forMT-TL1and 100% (1/1) formtDNAdeletion], 100% (1/1) forOAT, 95.2% (20/21) forCYP4V2, 72.7% (8/11) forCHMfemale carriers, 66.7% (2/3) forC1QTNF5, 57.1% (8/14) forPROM1, 53.8% (7/13) forPRPH2, 42.9% (3/7) forCERKL, 28.6% (2/7) forCDHR1, 20% (1/5) forRPE65, 4% (18/445) forABCA4.In contrast, ORT was not observed in any patients with photoreceptor-specific gene variants, such asRHO(n=13),USH2A(n=118),EYS(n=70),PDE6B(n=10),PDE6A(n=4),and others. CONCLUSION: These results illustrate a compelling association between the presence of ORT and IRDs caused by variants in RPE-specific genes, as well as non-RPE-specific genes. In contrast, IRDs caused by photoreceptor-specific genes are typically not associated with ORT occurrence. Further analysis revealed that ORT tends to manifest in IRDs with milder intraretinal pigment migration (IPM), a finding that is typically associated with RPE-specific genes. These findings regarding ORT, genetic factors, atrophic patterns in the fundus, and IPM provide valuable insight into the complex etiology of IRDs. Future prospective studies are needed to further explore the association and underlying mechanisms of ORT in these contexts.

Clinical value of optical coherence tomography in the early diagnosis of cervical cancer and precancerous lesions: a cross-sectional study.

Background: This study aimed to measure the accuracy of optical coherence tomography (OCT) in the early diagnosis of high-grade cervical lesions and assess its diagnostic value in the triage of high-risk HPV infection. Method: From Jan 2019 to Jan 2021, women who visited the gynecology clinics of 2 hospitals for colposcopy were invited to participate in this study. Women aged 35 to 64 years old who were sexually active and had an intact cervix with a diameter of more than or equal to 2 cm were included in this study. Additionally, individuals with abnormal cytology, positive HPV test results, or other clinically suspicious symptoms or signs were referred. All participants were examined before colposcopy using OCT. Biopsy and/or ECC were conducted under colposcopy. We used the results of histopathology as the gold standard and assessed the accuracy of OCT. Results: Overall, 883 women were included in the analysis. Approximately 13.25% of women were ASCUS+ in cytological assessments, and 22.31% were positive for high-risk HPV. Nearly 15.18% of women were positive in OCT. Of them, 27 women were diagnosed with CIN2, and 33 were diagnosed with CIN3+ lesions. Among HPV-positive women, the detection rates for CIN2+ and CIN3+ were much lower for those who were negative in OCT, compared with NILM cytology (CIN2+: 20.0% vs. 30.0%, P=0.002, and CIN3+: 18.2% vs. 27.3%, P=0.013). Among women who were positive for HPV16/18, the detection rate for CIN2+ was much lower for negative OCT, compared with NILM cytology (8.3% vs.15.0%, P=0.005). Compared to HPV and cytological tests, HPV combined with OCT had higher specificity for detecting CIN2+ and CIN3+ (96.1% vs. 93.2%, P=0.002; 93.8% vs. 91.3%, P=0.013). OCT triage after HPV genotyping had the highest AUC for detecting CIN2+ and CIN3+ cases among patients with high-risk HPV infection (0.921, 0.920). Conclusion: OCT is an accurate test for the early diagnosis of high-grade cervical lesions and has great diagnostic value in the triage of patients with high-risk HPV infection.

Comparison of Retinal Nerve Fiber Layer and Ganglion Cell Complex Rates of Change in Patients with Moderate to Advanced Glaucoma.

PURPOSE: To compare ganglion cell complex (GCC) and retinal nerve fiber layer (RNFL) rates of change (RoC) in eyes with central or moderate to advanced glaucoma. DESIGN: Prospective cohort study. PARTICIPANTS: 918 matched macular and RNFL OCT scan pairs from 109 eyes (109 patients) enrolled in the Advanced Glaucoma Progression Study with ≥2 years of follow-up and ≥4 OCT scans. METHODS: We exported GCC and RNFL thickness measurements in 49 central macular superpixels and 12 RNFL clock-hour sectors, respectively. We applied our latest Bayesian hierarchical longitudinal model to estimate population and subject-specific baseline thickness (intercepts) and rates of change (RoC) in macular superpixels and RNFL sectors. Global RNFL and GCC RoC were analyzed in a single bivariate longitudinal model to properly compare them accounting for the correlation between their RoC. MAIN OUTCOME MEASURES: Proportion of significant negative (deteriorating) and positive (improving) RoC expressed in µm/year. Standardized RoC were calculated by dividing RoC by the corresponding population SD. Analyses were repeated in eyes with visual field mean deviation (MD) ≤-6 and >-6 dB. RESULTS: Average (SD) 24-2 visual field MD and follow-up length were -8.6 (6.3) dB and 4.2 (0.5) years, respectively. Global RNFL RoC (-0.70 µm/year) were faster than GCC (-0.44 µm/year) (p<.001); corresponding normalized RoC were not significantly different (p=0.052). In bivariate analysis, patients with a significant negative global RNFL RoC (n=63, 57%) or GCC (n=56, 51%) frequently did so for both outcomes (n=49, 45%). The average proportion of significantly decreasing RNFL sectors within an eye was 30.7% in eyes with MD >-6 dB compared to 20.5% in those with MD ≤-6 dB (p=0.014); the proportions for GCC superpixels were 21.1% vs. 18.7%, respectively (p=0.63). CONCLUSIONS: Both GCC and RNFL measures can detect structural progression in glaucoma patients with central damage or moderate to advanced glaucoma. The clinical utility of RNFL imaging decreases with worsening severity of glaucoma.

A simple computational model for scleral stiffness assessments via air-puff deformation OCT.

Introduction: The mechanical properties of the sclera are related to its structural function, and changes to these properties are believed to contribute to pathologies such as myopia. Air-puff deformation imaging is a tool that uses an imaging system coupled with an air-puff excitation source to induce and measure deformation in a tissue in vivo. Typically used for the study of the cornea's mechanical properties and IOP, this tool has been proposed as a method to evaluate scleral stiffness. Methods: In this work, we present a computational model of the rabbit eye to assess scleral deformation under air-puff. Parametric studies were conducted to evaluate the effects of material properties, intraocular pressure, and other parameters on the deformation response. Output from the model was also compared to experimental measurements of air-puff deformation in rabbit eyes under varying IOP. Results: Central deformation response was found to be most influenced by material properties of the sclera (at site of air-puff and posterior), thickness, and IOP, whereas deformation profile was most influenced by material properties. Experimental and simulated IOP dependence were found to be similar (RMSE = 0.13 mm). Discussion: Scleral APDI could be a useful tool for quick in vivo assessment of scleral stiffness.

Assessment of Effectiveness of the Algorithm for Automated Quantitative Analysis of Metallic Strut Tissue Short-Term Coverage with Intravascular Optical Coherence Tomography.

Background: Due to its high resolution, optical coherence tomography (OCT) is the most suitable modality for neointimal coverage assessments. Evaluation of stent healing seems crucial to accurately define their safety profile since delayed healing is connected with stent thrombosis. This study aimed to present an algorithm for automated quantitative analysis of stent strut coverage at the early stages of vessel healing in intravascular OCT. Methods: A set of 592 OCT frames from 24 patients one month following drug-eluting stent implantation was used to assess the algorithm's effectiveness. Struts not covered on any side or covered but only on one side were categorized as uncovered. The algorithm consists of several key steps: preprocessing, vessel lumen segmentation, automatic strut detection, and measurement of neointimal thickness. Results: The proposed algorithm proved its efficiency in lumen and stent area estimation versus manual reference. It showed a high positive predictive value (PPV) (89.7%) and true positive rate (TPR) (91.4%) in detecting struts. A qualitative assessment for covered and uncovered struts was characterized by high TPR (99.1% and 80%, respectively, for uncovered and covered struts) and PPV (77.3% and 87%). Conclusions: The proposed algorithm demonstrated good agreement with manual measurements. Automating the stent coverage assessment might facilitate imaging analysis, which might be beneficial in experimental and clinical settings.

Evaluation of Anatomical and Tomographic Biomarkers as Predictive Visual Acuity Factors in Eyes with Retinal Vein Occlusion Treated with Dexamethasone Implant.

Background: This prospective study evaluated the impact of anatomical and tomographic biomarkers on clinical outcomes of intravitreal dexamethasone implants in patients with macular edema secondary to retinal vein occlusion (RVO). Methods: The study included 46 patients (28 with branch RVO (BRVO) and 18 with central RVO (CRVO)). Best corrected visual acuity (BCVA) significantly improved from a mean baseline of 0.817 ± 0.220 logMAR to 0.663 ± 0.267 logMAR at six months and 0.639 ± 0.321 logMAR at twelve months (p < 0.05). Central retinal thickness (CRT) showed a significant reduction from 666.2 ± 212.2 µm to 471.1 ± 215.6 µm at six months and 467 ± 175.7 µm at twelve months (p < 0.05). No significant differences were found in OCT biomarkers between baseline and follow-ups. Results: The study analysed improvements in visual acuity relative to baseline biomarkers. At six months, ellipsoid zone disruption (EZD) was significant for all subgroups. Disorganization of retinal inner layers (DRIL), external limiting membrane (ELM) disruption, macular ischemia (MI), CRT, and BRVO showed significance for any improvement, while DRIL and ELM were significant for changes greater than 0.3 logMAR (p < 0.05). At twelve months, EZD remained significant for all subgroups. ELM, MI, CRT, and BRVO were significant for any improvement, while MI and BRVO were significant for changes greater than 0.3 logMAR (p < 0.05). Hyperreflective foci were not statistically significant at either time point (p > 0.05). Conclusions: The regression model suggested that MI and CRVO could be negative predictive factors for visual outcomes, while ELM and EZD were associated with BCVA improvement one-year post-treatment.

Age-Related Retinal Layer Thickness Changes Measured by OCT in APPNL-F/NL-F Mice: Implications for Alzheimer's Disease.

In Alzheimer's disease (AD), transgenic mouse models have established links between abnormalities in the retina and those in the brain. APPNL-F/NL-F is a murine, humanized AD model that replicates several pathological features observed in patients with AD. Research has focused on obtaining quantitative parameters from optical coherence tomography (OCT) in AD. The aim of this study was to analyze, in a transversal case-control study using manual retinal segmentation via SD-OCT, the changes occurring in the retinal layers of the APPNL/F-NF/L AD model in comparison to C57BL/6J mice (WT) at 6, 9, 12, 15, 17, and 20 months of age. The analysis focused on retinal thickness in RNFL-GCL, IPL, INL, OPL, and ONL based on the Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. Both APPNL-F/NL-F-model and WT animals exhibited thickness changes at the time points studied. While WT showed significant changes in INL, OPL, and ONL, the AD model showed changes in all retinal layers analyzed. The APPNL-F/NL-F displayed significant thickness variations in the analyzed layers except for the IPL compared to related WT. These thickness changes closely resembled those found in humans during preclinical stages, as well as during mild and moderate AD stages, making this AD model behave more similarly to the disease in humans.

Factors Affecting Disease Stability After Intravitreal Brolucizumab Injection for Refractory Neovascular Age-Related Macular Degeneration.

INTRODUCTION: The purpose of this study is to identify the factors affecting neovascular age-related macular degeneration (nAMD) disease stability after brolucizumab treatment. METHODS: We retrospectively analyzed the medical records of 31 patients (31 eyes) with recalcitrant nAMD who were switched to brolucizumab after conventional anti-vascular endothelial growth factor (VEGF) treatment. We divided patients into two groups by treatment extension (TE) period: group 1 with TE < 12 weeks (N = 16) and group 2 with TE ≥ 12 weeks (N = 15). We compared outcomes between the groups at 2, 4, 8, and 12 weeks, including morphological characteristics of choroidal neovascularization (CNV). Logistic regression analysis identified factors associated with TE ≥ 12 weeks. RESULTS: Group 2 had a significantly greater proportion of patients with dry macula (subretinal and intraretinal fluids absent) than group 1 (60 vs. 12.5%) at 2 weeks (P < 0.05). Best-corrected visual acuity (BCVA) and subfoveal choroidal thickness (SFCT) did not differ significantly between groups at all timepoints. Central subfield retinal thickness (CST) was significantly lower in group 2 at 2 (237.1 vs. 280.8 µm; P < 0.05), 4 (224.0 vs. 262.9 µm; P < 0.05), and 8 weeks (216.8 vs. 331.1 µm; P < 0.05). Group 2 had less vessel area (0.63 vs. 1.27 mm2; P < 0.05) and total vessel length (0.22 vs. 0.42 mm; P < 0.05). Choriocapillaris flow deficit (CCFd) was significantly lower in group 2 (42.7 vs. 48.2%; P < 0.05). Dry macula at 2 weeks (odds ratio [OR] = 8.3; P < 0.05) and a lower CCFd (OR = 0.73; P < 0.05) were associated with TE ≥ 12 weeks. CONCLUSIONS: Early fluid-free status after switching to brolucizumab and choriocapillary function around CNV were prognostic factors for disease stability in nAMD refractory to anti-VEGF treatment.

PCSK9 and Coronary Artery Plaque-New Opportunity or Red Herring?

PURPOSE OF REVIEW: Although the clinical benefit of reducing low-density lipoprotein cholesterol (LDLc) in patients with coronary artery disease (CAD) is well-established, the impact on plaque composition and stability is less clear. Our narrative review aimed to assess the clinical effects of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on coronary plaque characteristics specifically focusing from atheroma progression to regression and stabilization. RECENT FINDINGS: The combination of statin therapy and PCSK9 inhibitors (evolocumab and alirocumab) promotes plaque stability in patients following an acute coronary syndrome. The GLAGOV study highlighted the relationship between achieved LDLc levels and changes in percentage atheroma volume. Similarly, the PACMAN-AMI study concluded that the qualitative and quantitative changes in coronary plaque were associated with the levels of LDLc. Assessing the severity of coronary artery stenosis and the extent of atherosclerotic burden by means of imaging techniques (e.g., IVUS, OCT and near-infrared spectroscopic) have significantly advanced our understanding of the benefits from promoting plaque regression and achieving to features of plaque stabilization through increasingly intensive lipid-lowering strategies.

Deep Learning-Based Clustering of OCT Images for Biomarker Discovery in Age-Related Macular Degeneration (PINNACLE Study Report 4).

Purpose: We introduce a deep learning-based biomarker proposal system for the purpose of accelerating biomarker discovery in age-related macular degeneration (AMD). Design: Retrospective analysis of a large data set of retinal OCT images. Participants: A total of 3456 adults aged between 51 and 102 years whose OCT images were collected under the PINNACLE project. Methods: Our system proposes candidates for novel AMD imaging biomarkers in OCT. It works by first training a neural network using self-supervised contrastive learning to discover, without any clinical annotations, features relating to both known and unknown AMD biomarkers present in 46 496 retinal OCT images. To interpret the learned biomarkers, we partition the images into 30 subsets, termed clusters, that contain similar features. We conduct 2 parallel 1.5-hour semistructured interviews with 2 independent teams of retinal specialists to assign descriptions in clinical language to each cluster. Descriptions of clusters achieving consensus can potentially inform new biomarker candidates. Main Outcome Measures: We checked if each cluster showed clear features comprehensible to retinal specialists, if they related to AMD, and how many described established biomarkers used in grading systems as opposed to recently proposed or potentially new biomarkers. We also compared their prognostic value for late-stage wet and dry AMD against an established clinical grading system and a demographic baseline model. Results: Overall, both teams independently identified clearly distinct characteristics in 27 of 30 clusters, of which 23 were related to AMD. Seven were recognized as known biomarkers used in established grading systems, and 16 depicted biomarker combinations or subtypes that are either not yet used in grading systems, were only recently proposed, or were unknown. Clusters separated incomplete from complete retinal atrophy, intraretinal from subretinal fluid, and thick from thin choroids, and, in simulation, outperformed clinically used grading systems in prognostic value. Conclusions: Using self-supervised deep learning, we were able to automatically propose AMD biomarkers going beyond the set used in clinically established grading systems. Without any clinical annotations, contrastive learning discovered subtle differences between fine-grained biomarkers. Ultimately, we envision that equipping clinicians with discovery-oriented deep learning tools can accelerate the discovery of novel prognostic biomarkers. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.