Vincent Daien

Les vaisseaux rétiniens sont accessibles par la visualisation du fond d'œil grâce notamment aux rétinophotographies. Cette visualisation donne donc un accès direct à l'étude de la microcirculation humaine. Depuis 1999, le logiciel IVAN® permet une analyse «semi-automatique» du calibre vasculaire rétinien. L'analyse de la littérature retrouve que les variations du calibre vasculaire rétinien sont le reflet cumulatif du poids de naissance, de facteurs génétiques, de l'âge, des facteurs de risques cardiovasculaires, de la fonction rénale et de l'inflammation. Les méta-analyses d'études épidémiologiques suggèrent un rôle prédictif des calibres vasculaires rétiniens sur les évènements cardiovasculaires : un calibre artériel rétinien étroit serait prédictif de maladie coronaire chez les femmes et augmenterait la mortalité cardiovasculaire globale ; un large calibre veineux serait prédictif d'accident vasculaire cérébral. Cette thèse a pour objectif d'approfondir les connaissances sur les déterminants des calibres vasculaires rétiniens chez les sujets indemnes d'athérosclérose clinique (antécédent de maladie coronaire, d'accident vasculaire cérébral, d'artériopathie des membres inférieurs). Depuis 2007, en partenariat avec l'université de Melbourne, nous avons acquis le logiciel IVAN® et l'agrément permettant son utilisation en recherche clinique et épidémiologique a été obtenu en 2008. Dans un premier article, nous avons mis en évidence une relation linéaire entre calibre artériel et veineux et fonction rénale mesurée par des méthodes gold standard (filtration glomérulaire mesurée par la clairance de 99mTc-DTPA et ratio albuminurie/créatinurie) sur 80 sujets de la cohorte de médecine interne-hypertension artérielle de l'hôpital Lapeyronie, suggérant des déterminants communs de ces lésions précoces d'organes cibles. Dans un deuxième article, nous avons tout d'abord confirmé le lien entre dilatation veineuse rétinienne et inflammation systémique, puis observé une relation entre calibre artériel étroit et stress oxydatif sur les participants de la cohorte POLA (pathologies oculaires liées à l'âge). Cela est d'une importance particulière car cela suggère que la microcirculation rétinienne, dont des associations avec la macrocirculation carotidienne et cardiaque ont été retrouvées, serait particulièrement sensible au stress oxydatif et à l'inflammation, de façon indépendante des facteurs de risques cardiovasculaires. Dans un troisième article, nous avons retrouvé une relation entre malnutrition biologique et dilatation veineuse rétinienne sur les participants de la cohorte POLA. Cela suggère que des remaniements microcirculatoires précoces pourraient être un mécanisme associé à l'augmentation du risque cardiovasculaire observé chez les sujets âgés souffrants de malnutrition. Les caractéristiques techniques du logiciel IVAN® limitent sa généralisation en médecine, mais son utilisation permet d'approfondir les connaissances sur les déterminants des variations de calibre des vaisseaux de la rétine. Le futur challenge des études sur la vascularisation rétinienne utilisera probablement l'étude de la géométrie vasculaire rétinienne afin d'améliorer la compréhension de microcirculation humaine.

To map time-resolved tear proteome changes during corneal epithelial wound healing after photorefractive keratectomy (PRK) and nominate tear-based biomarker panels with translational potential. Tears from 10 healthy adults were collected before PRK (Pre), ∼30-60 minutes after PRK (D0), and day 3 (D3) using Schirmer strips. Proteins were extracted (SP3), trypsin-digested, and analyzed by DIA on an Evosep One-timsTOF HT platform. DIA-NN (1% FDR) provided identification/quantification. Paired contrasts (Pre vs. D0; Pre vs. D3) defined differentially abundant proteins (adjusted P < 0.05; |fold change|≥2) for pathway enrichment. A stringent screen (adjusted P < 0.001; FC>2.5) and UniProt-based annotation distinguished secreted versus intracellular candidates. Across 2025 identified proteins, 909 (∼45%) were significantly modulated. D0 tears showed an "injury/ECM" program (e.g., TGFBI, lumican, keratocan, fibrinogen chains, complement C8B, APOA1), whereas D3 shifted toward remodeling and epithelial polarity with regulated proteolysis (e.g., SERPINA3, MMP7, THBS1, MUC5B, CXCL17). A subset persisted across time points (e.g., A2M, haptoglobin, OLFML3). Intracellular signatures paralleled phase transitions: D0 was enriched for chromatin/DNA-repair and RNA-binding proteins (histones, XRCC5/Ku80, HNRNPs), whereas D3 highlighted transport/cytoskeletal factors linked to apical remodeling and fluid/ion handling (AQP5, NHERF1/EBP50, ANO1/TMEM16A, ACTN1, RDX). H6PD was elevated at both D0 and D3. Time-stamped, tear-accessible biomarker panels emerge from this analysis: early-injury (TGFBI, lumican/keratocan, fibrinogen/complement), sustained (A2M, haptoglobin, OLFML3), and late-remodeling/epithelial (SERPINA3, MMP7, THBS1, MUC5B, CXCL17), with complementary intracellular markers (AQP5/NHERF1/ANO1). These candidates may support perioperative monitoring, risk stratification (delayed closure, stromal haze), and phase-adapted therapy after PRK, warranting prospective clinical validation.

Introduction: The aim of the study was to evaluate clinical and biometric factors leading to a prediction error related to lens position in pars plana vitrectomy. Methods: This study was conducted as a consecutive retrospective case series at the Department of Ophthalmology, Montpellier University Hospital. All medical files and PCI biometrical reports from a single surgeon were reviewed from 2017 to 2019. Patients who had phacoemulsification with the ASPHINA 509 MP® intraocular lens were selected and stratified into 3 groups: phacoemulsification alone (group 1), phacoemulsification and vitrectomy with gas tamponade (group 2), and phacoemulsification and vitrectomy without tamponade (group 3). Clinical factors and biometry factors from initial and final biometry were collected. Refractive error, actual lens position, C constant, axial length delta, and pre-operative and post-operative anterior and posterior segment variation parameters were calculated. Results: A total of 140 eyes were analyzed, 90 in group 1, and 25 in group 2 and 3. The mean prediction error was 0.10 ± 0.55 D (group 1); −0.36 ± 0.74 D (group 2); and −0.12 ± 0.54 D (group 3) with p < 0.05 for group 1 vs. group 2. The mean actual lens position was 5.25 ± 0.29 mm; 5.66 ± 0.60 mm; and 5.50 ± 0.43 mm for the 3 groups, respectively (p < 0.001). Axial length delta was −0.10 ± 0.13 mm in group 1, −0.062 ± 0.20 mm in group 2, and −0.022 ± 0.17 mm in group 3 (p = 0.015). Multilinear regression analysis found a significant and independent influence of vitrectomy and gas tamponade on prediction error. Conclusion: Myopic shift in the case of vitrectomy is multifactorial, effective lens position is modified by vitrectomy and vitreous refractive index is changing. The integration of these data in formulas may improve refractive outcome after cataract and vitrectomy surgery.

Introduction Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for diabetic macular edema (DME). We investigated the effect of initial glycosylated hemoglobin (HbA1c) level and glomerular filtration rate (GFR) on treatment outcomes in patients with DME receiving anti-VEGF injections in routine clinical practice. Methods A retrospective analysis of data from the prospective, multi-center, observational Fight Retinal Blindness! registry was performed. A total of 178 eyes with DME treated with anti-VEGF agents (ranibizumab or aflibercept) from 1 January 2010 to 31 March 2019 were enrolled in the analysis, with the long study period to allow for up to 24 months of follow-up. Data for eyes were tracked in the Fight Retinal Blindness! registry, and clinical parameters were collected by using local software. Changes in visual (best-corrected visual acuity [BCVA], in letters) and anatomic outcomes (central subfield thickness [CST], in microns) between subgroups of patients according to baseline HbA1c level (≤ 7% vs. > 7%) and GFR (> vs. ≤ 60 ml/min/m² at 24 months were assessed. Results The multivariate adjusted mean improvement in BCVA at 24 months of treatment was + 5.2 and + 6.8 letters in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.541), and + 6.9 and + 6.4 letters in subgroups with GFR > 60 and < 60 ml/min/1.73 m², respectively (p = 0.852). The multivariate adjusted mean CST reduction was − 89.9 and − 76.4 µm in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.505), and − 85 and − 115 µm in subgroups with baseline GFR > 60 and ≤ 60 ml/min/1.73 m², respectively (p = 0.130). Conclusion These results seem to indicate that visual and anatomical improvement in patients receiving intravitreal VEGF inhibitors for DME are independent of baseline HbA1c level and GFR, leading to the conclusion that high HbA1c levels or low GFR should not dictate injection timing in routine clinical practice. This study offers valuable insights for ophthalmologists, enabling a personalized treatment approach and optimizing DME patient outcomes.

Background/aims To investigate the association of commonly used systemic medications with prevalent age-related macular degeneration (AMD) in the general population. Methods We included 38 694 adults from 14 population-based and hospital-based studies from the European Eye Epidemiology consortium. We examined associations between the use of systemic medications and any prevalent AMD as well as any late AMD using multivariable logistic regression modelling per study and pooled results using random effects meta-analysis. Results Between studies, mean age ranged from 61.5±7.1 to 82.6±3.8 years and prevalence ranged from 12.1% to 64.5% and from 0.5% to 35.5% for any and late AMD, respectively. In the meta-analysis of fully adjusted multivariable models, lipid-lowering drugs (LLD) and antidiabetic drugs were associated with lower prevalent any AMD (OR 0.85, 95% CI=0.79 to 0.91 and OR 0.78, 95% CI=0.66 to 0.91). We found no association with late AMD or with any other medication. Conclusion Our study indicates a potential beneficial effect of LLD and antidiabetic drug use on prevalence of AMD across multiple European cohorts. Our findings support the importance of metabolic processes in the multifactorial aetiology of AMD.

Background: The dramatic increase in intravitreal injections (IVTs) has been accompanied by a greater need for safer procedures. The ongoing debate about topical antibiotic prophylaxis after IVTs emphasizes the importance of large-scale studies. We aimed to study the role of topical antibiotic prophylaxis in reducing the risk of acute endophthalmitis after IVTs. Methods: Population-based cohort study, in France, from 2009 to 2018, including all French patients receiving IVTs of corticosteroids or anti-VEGF agents. Results: A total of 5,291,420 IVTs were performed on 605,434 patients. The rate of topical antibiotic prophylaxis after IVTs progressively decreased during the study period, with a sharp drop in 2014 (from 84.6% in 2009 to 27.4% in 2018). Acute endophthalmitis occurred in 1274 cases (incidence rate = 0.0241%). Although antibiotic prophylaxis did not alter the risk of endophthalmitis (p = 0.06), univariate analysis showed an increased risk after fluoroquinolone and aminoglycoside prophylaxis. This increased risk was not found in multivariate analysis. However, we observed an increased risk related to the use of fixed combinations of fluoroquinolones and aminoglycosides with corticosteroids (IRR = 1.89; 95% CI = 1.57–2.27%, antibiotics combined with corticosteroids). Conclusion: These results are consistent with the literature. Endophthalmitis rates after IVTs did not decrease with topical antibiotic prophylaxis. The use of a combination of antibiotics and corticosteroids doubles the risk of endophthalmitis and should be avoided. Avoiding antibiotic prophylaxis would reduce the costs and the potential risks of antibiotic resistance.

Purpose. To evaluate risk factors associated with keratoconus in a monocentric cross-sectional case-control study. Methods. This observational study occurred from June 2019 to February 2021 in a university hospital (France). The case group consisted of 195 patients with keratoconus in at least one eye who were followed up by a corneal specialist. The control group consisted of 195 patients without any evidence of keratoconus on slit-lamp examination and corneal topography, who were matched 1 : 1 to controls by age and sex. Data were collected by a self-completed paper questionnaire before the consultation, and a multivariate logistic regression was performed. Results. Multivariate analysis revealed significant associations of keratoconus with family history (odds ratio [OR] = 22.2, ), rubbing eyes (OR = 10.9, ), allergy (any kind) (OR = 3.80, ), smoking exposure (OR = 2.08, ), and dry eyes (OR = 1.77, f). The worst eye was associated with the more rubbed eye ( ) and the more pressed eye during the night according to sleeping position ( ). Conclusion. This study confirmed the association between keratoconus and eye rubbing, family history, and allergy. It highlighted the role of pressure on the eyes during sleep. Other less known risk factors such as dry eyes and smoking exposure should be explored in future studies.

We aimed to compare measurements from three of the most widely used software packages in the literature and to generate conversion algorithms for measurement of the central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) between SIVA and IVAN and between SIVA and VAMPIRE. We analyzed 223 retinal photographs from 133 human participants using both SIVA, VAMPIRE and IVAN independently for computing CRAE and CRVE. Agreement between measurements was assessed using Bland–Altman plots and intra-class correlation coefficients. A conversion algorithm between measurements was carried out using linear regression, and validated using bootstrapping and root-mean-square error. The agreement between VAMPIRE and IVAN was poor to moderate: The mean difference was 20.2 µm (95% limits of agreement, LOA, −12.2–52.6 µm) for CRAE and 21.0 µm (95% LOA, −17.5–59.5 µm) for CRVE. The agreement between VAMPIRE and SIVA was also poor to moderate: the mean difference was 36.6 µm (95% LOA, −12.8–60.4 µm) for CRAE, and 40.3 µm (95% LOA, 5.6–75.0 µm) for CRVE. The agreement between IVAN and SIVA was good to excellent: the mean difference was 16.4 µm (95% LOA, −4.25–37.0 µm) for CRAE, and 19.3 µm (95% LOA, 0.09–38.6 µm) for CRVE. We propose an algorithm converting IVAN and VAMPIRE measurements into SIVA-estimated measurements, which could be used to homogenize sets of vessel measurements obtained with different software packages.