Evaluation of intravitreal injections as a risk factor for capsular rupture during cataract surgery.

OBJECTIVE: To determine whether previous intravitreal injections are an independent risk factor for posterior capsular rupture (PCR) during cataract surgery after adjusting for known risk factors. DESIGN: Single-centre medical records analysis of a population-based cohort at a university-based referral centre. A retrospective cohort study has been conducted with inclusion of cataract surgeries done from January 1, 2005 to December 31, 2020 at the Department of Ophthalmology, Medical University of Graz, Austria. PARTICIPANTS: All consecutive cataract surgeries done in patients of at least 18 years of age from January 1, 2005 to December 31, 2020 have been included. METHODS: Association between previous intravitreal injections and PCR rates has been analysed through univariable and multivariable generalized estimating equations (GEE). Other investigated risk factors were age, combined surgery, pseudoexfoliation, surgeon's experience, and type of cataract surgery. RESULTS: A statistically significant higher rate of posterior capsular rupture during cataract surgery has been found in patients with previous intravitreal therapy compared with patients with no history of intravitreal therapy (OR 1.27, 95% CI 1.10-1.46, p = 0.008). However, after adjusting for confounding risk factors, no statistically significant effect was seen (OR 1.04, 95% CI 0.89-1.21, p = 0.664). CONCLUSION: We found no association between history of intravitreal injections and PCR during cataract surgery after adjusting for known risk factors. Further studies upon interactions between history of intravitreal injections and known risk factors for PCR, especially pseudoexfoliation, are needed.

Automated Measurement and Three-Dimensional Fitting of Corneal Ulcerations and Erosions via AI-Based Image Analysis.

PURPOSE: Artificial intelligence (AI)-tools hold great potential to compensate for missing resources in health-care systems but often fail to be implemented in clinical routine. Intriguingly, no-code and low-code technologies allow clinicians to develop Artificial intelligence (AI)-tools without requiring in-depth programming knowledge. Clinician-driven projects allow to adequately identify and address real clinical needs and, therefore, hold superior potential for clinical implementation. In this light, this study aimed for the clinician-driven development of a tool capable of measuring corneal lesions relative to total corneal surface area and eliminating inaccuracies in two-dimensional measurements by three-dimensional fitting of the corneal surface. METHODS: Standard slit-lamp photographs using a blue-light filter after fluorescein instillation taken during clinical routine were used to train a fully convolutional network to automatically detect the corneal white-to-white distance, the total fluorescent area and the total erosive area. Based on these values, the algorithm calculates the affected area relative to total corneal surface area and fits the area on a three-dimensional representation of the corneal surface. RESULTS: The developed algorithm reached dice scores >0.9 for an automated measurement of the relative lesion size. Furthermore, only 25% of conventional manual measurements were within a ± 10% range of the ground truth. CONCLUSIONS: The developed algorithm is capable of reliably providing exact values for corneal lesion sizes. Additionally, three-dimensional modeling of the corneal surface is essential for an accurate measurement of lesion sizes. Besides telemedicine applications, this approach harbors great potential for clinical trials where exact quantitative and observer-independent measurements are essential.

Measuring patient activation: the utility of the Patient Activation Measure administered in an interview setting.

BACKGROUND: Patient activation is an emerging field in healthcare research concerning knowledge, skills, and confidence of patients in managing their health. This is particularly important for patients with chronic diseases, who often require more complex care management and self-care skills. However, due to temporary or longer-lasting visual impairments, certain patient groups cannot answer a questionnaire independently. The main objective is to investigate the psychometric properties of the German Patient Activation Measure® (PAM) survey in an everyday clinical setting where it has to be read aloud. METHODS: Outpatients with macular edema participated in this questionnaire-based cross-sectional study. The study assessed patient activation by the PAM® survey, self-rated health, self-efficacy, quality of life, and general mood. Interviewers read questionnaires aloud to patients. Psychometric properties of the PAM® survey were investigated by item response theory (IRT), Cronbach's α and trait-trait correlations. RESULTS: The analysis included N = 554 patients. Median age was 69 (IQR 62.0-76.0) years and mean overall activation score 74.1 (SD 13.7). All items showed ceiling effects. Empirical reliability from the IRT model and Cronbach's α were 0.75. The PAM® survey showed a Spearman correlation of 0.54 with self-efficacy, 0.51 with quality of life and 0.34 with general mood. CONCLUSION: The read-aloud PAM® survey has been shown to provide to adequate measurement precision and convergent validity to be used as a screening tool in an everyday clinical setting. Objective assessment in an interview setting with the PAM® survey is possible. PAM® items are good in distinguishing lower to middle activated patients, but not patients with high activation. Further, issues with structural validity need more investigation.

Protective Effect of Amblyopia on Age-Related Macular Degeneration.

PURPOSE: Our aim was to evaluate whether patients with age-related macular degeneration (AMD) and cooccurrent amblyopia are more likely to have diseases diagnosed on both the ipsilateral and the contralateral side in a large Austrian database. DESIGN: Retrospective cross-sectional study. METHODS: Setting: Institutional practice. PATIENT POPULATION: Medical records of all patients who visited the Department of Ophthalmology of the Medical University of Graz between December 1996 and June 2021 were searched for the co-occurrence of AMD and amblyopia. MAIN OUTCOME MEASURES: Data from patients with AMD diagnosed on 1 eye side were used for further analysis. Spectral-domain optical coherence tomography images were analyzed to confirm the lateral asymmetry of AMD. RESULTS: A total of 327,443 patients were screened for the co-occurrence of AMD and amblyopia. Of them, 8742 patients had AMD diagnosed on 1 eye side and 5051 patients had unilateral amblyopia. In total, 163 patients were found to have AMD diagnosed on 1 side and unilateral amblyopia in combination. Of these, 126 patients had AMD and amblyopia on contralateral sides and 37 had AMD and amblyopia on the ipsilateral side (P < .001). CONCLUSIONS: Less amblyopic patients had AMD diagnosed on the amblyopic eye compared with the nonamblyopic eye. In cases of lateral asymmetry, the nonamblyopic eye is more likely to have the more advanced form of AMD.

Deep phenotyping of PROM1-associated retinal degeneration.

BACKGROUND/AIMS: The purpose of this study was to investigate retinal structure in detail of subjects with autosomal-dominant (AD) and autosomal-recessive (AR) PROM1-associated retinal degeneration (PROM1-RD), study design: institutional, cross-sectional study. METHODS: Four eyes from four subjects (three with AD and one with AR) PROM1-RD were investigated by ophthalmic examination including best-corrected visual acuity (BCVA) and multimodal retinal imaging: fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT) and adaptive optics scanning light ophthalmoscopy. Quantitative assessment of atrophic lesions determined by FAF, thickness of individual retinal layers and cone photoreceptor quantification was performed. RESULTS: BCVA ranged from 20/16 to 20/200. Initial pathological changes included the presence of hyperautofluorescent spots on FAF imaging, while later stages demonstrated discrete areas of atrophy. In all patients, thinning of the outer retinal layers on SD-OCT with varying degrees of atrophy could be detected depending on disease-causing variants and age. Cone density was quantified both in central and/or at different eccentricities from the fovea. Longitudinal assessments were possible in two patients. CONCLUSIONS: PROM1-RD comprises a wide range of clinical phenotypes. Depending on the stage of disease, the cone mosaic in PROM1-RD is relatively preserved and can potentially be targeted by cone-directed interventions.

Progression of PROM1-Associated Retinal Degeneration as Determined by Spectral-Domain Optical Coherence Tomography Over a 24-Month Period.

PURPOSE: To evaluate the progression of atrophy as determined by spectral-domain optical coherence tomography (SD-OCT) in patients with molecularly confirmed PROM1-associated retinal degeneration (RD) over a 24-month period. DESIGN: International, multicenter, prospective case series. METHODS: A total of 13 eyes (13 patients) affected with PROM1-associated RD were enrolled at 5 sites and SD-OCT images were obtained at baseline and after 24 months. Loss of mean thickness (MT) and intact area were estimated after semi-automated segmentation for the following individual retinal layers in the central subfield (CS), inner ring, and outer ring of the ETDRS grid: retinal pigment epithelium (RPE), outer segments (OS), inner segments (IS), outer nuclear layer (ONL), inner retina (IR), and total retina (TR). RESULTS: Statistically significant losses of thickness of RPE and TR were detected in the CS and inner ring and of ONL and IS in the outer ring (all P < .05); a statistically significant decrease in the intact area of RPE and IS was observed in the inner ring, and of ONL in the outer ring (all P < .05); the change in MT and the intact area of the other layers showed a trend of decline over an observational period of 24 months. CONCLUSIONS: Significant thickness losses could be detected in outer retinal layers by SD-OCT over a 24-month period in patients with PROM1-associated retinal degeneration. Loss of thickness and/or intact area of such layers may serve as potential endpoints for clinical trials that aim to slow down the disease progression of PROM1-associated retinal degeneration.

Idebenone Treatment in Patients with OPA1-Dominant Optic Atrophy: A Prospective Phase 2 Trial.

The aim of this study was to evaluate the therapeutic effect of idebenone in patients with OPA1-dominant optic atrophy (DOA). Sixteen patients with genetically confirmed OPA1-DOA were treated with 900 mg idebenone daily for 12 months. The primary endpoint was the best recovery/least deterioration of visual acuity. Secondary endpoints were the changes of visual acuity, colour vision, contrast sensitivity, visual field, peripapillary retinal nerve fibre layer thickness (pRNFLT), and visual-related quality of life. For the primary endpoint, a significant increase was observed for the right eye (p = .0027), for the left eye (p = .0111) and for the better-seeing eye (p = .0152). For visual fields, a significant improvement was observed for the left eye between baseline and 9 months (p = .0038). Regarding pRNFLT, a significant decrease was found for the left eye between baseline and 3 months (p = .0413) and between baseline and 6 months (p = .0448). In the visual function questionnaire, a significant improvement was observed in the subscale general vision (p = .0156) and in the composite score (p = .0256). In conclusion, best recovery of visual acuity improved, even though the amount of improvement was small. Furthermore, a maintenance of visual function after 12 months of idebenone intake could be observed as well as a significant improvement in vision-related quality of life.Whether this effect is due to idebenone treatment, the placebo effect, or is explainable by the natural progression of DOA, remains unclear. Trial registration: EU Clinical Trials Register, EudraCT Number: 2019-001493-28.

Treatment of myopic choroidal neovascularization: a network meta-analysis and review.

PURPOSE: This is, to our knowledge, the first network meta-analysis aiming to compare all treatment modalities for myopic choroidal neovascularization (CNV). METHODS: After the electronic databases were searched, two independent reviewers screened titles, abstracts, full-texts, and extracted information. Primary endpoints were change in visual outcome and central retinal thickness. We used a network meta-analysis to compare treatment outcomes in the early (≤ 6 months) and late (> 6 months) phase. RESULTS: We included 34 studies (2,098 eyes) in our network meta-analysis. In the early phase, the use of anti-VEGF led to a gain of 14.1 letters (95% CI, 10.8-17.4) compared to untreated patients (p < 0.0001), 12.1 letters (95% CI, 8.3-15.8) to photodynamic therapy (PDT) (p < 0.0001), 7.5 (95% CI, 1.2-13.8) letters to intravitreal triamcinolone acetonide (TCA) (p = 0.019), and - 2.9 letters (95% CI, - 6.0-0.2) to the combination of anti-VEGF and PDT (p = 0.065). In the later phase, these results were largely maintained. There were no significant differences in visual outcomes between patients treated with 1 + PRN and 3 + PRN. However, the 1 + PRN group received 1.8 (SD 1.3), while the 3 + PRN group received 3.2 (SD 0.9) injections within 12 months (p < 0.0001). CONCLUSION: This network meta-analysis confirms that anti-VEGF is the most effective treatment for myopic CNV using the 1 + PRN treatment strategy.

Perioperative Insulin Regimens in Patients With Insulin-Treated Type 2 Diabetes Mellitus Hospitalized for a Short Time for Minor Eye Surgery.

BACKGROUND: Elective surgery in patients with insulin-treated type 2 diabetes mellitus (T2D) and the admission period in the hospital, comprise a distinctive and challenging situation for physicians, nurses, as well as for the patients themselves. There is a lack of widely accepted evidence-based and standardized approach of care in regard to perioperative management of patients with insulin-treated T2D. METHODS: The main purpose of this proof-of-concept study was to investigate whether a standardized insulin and meal regimen on the day of surgery leads to a better management of diabetes in terms of blood glucose (BG) levels. Two different insulin and meal regimens-group A with half of insulin dose given with a standardized postoperative meal and group B with a custom preoperative breakfast and full insulin dose-were compared with Group C with routine care (no meal and no insulin injection on the day of surgery). Each group consisted of 12 to 15 patients. BG measurements were performed pre- and immediately postoperatively, before meals and at bedtime. RESULTS: Both standardized and well-defined insulin and meal regimens resulted in better average BG levels in the perioperative period, especially in the morning after the surgery. CONCLUSIONS: In this study, we observed that a standardized perioperative insulin regimen efficiently lowered postoperative BG levels. Providing a custom breakfast and a full insulin dose resulted in lower postoperative BG levels. These approaches were not associated with an increase in hypoglycemic events. Physicians and nursing staff gave positive feedback to the structured and well-defined approaches.

[Diagnosis, treatment and monitoring of diabetic eye disease (Update 2023)]. / Diagnostik, Therapie und Verlaufskontrolle der diabetischen Augenerkrankung (Update 2023).

Diabetes mellitus can cause diabetic retinopathy, diabetic macular edema, optic neuropathy, cataract or dysfunction of the eye muscles. The incidence of these disorders correlates with disease duration and quality of metabolic control. Regular ophthalmological examinations are needed to prevent sight-threatening advanced stages of diabetic eye diseases.

Common Benign Melanocytic and Non-Melanocytic Skin Tumors among the Elderly: Results of the Graz Study on Health and Aging.

BACKGROUND AND OBJECTIVES: Benign skin tumors are the most common skin findings and contribute to the major reasons for consulting a dermatologist. However, the frequency of benign skin tumors concerning different body areas and their relationship with sun-related behavior have not been sufficiently characterized. We aimed to improve knowledge about the anatomic distribution of the most frequently occurring benign skin tumors among a healthy predominant elderly population. Furthermore, we investigated associations with sun-related habits. METHODS: In total, 100 participants, 37 men, and 63 women (mean age: 67.2 years; range: 46-86 years) were enrolled in the Graz Study on Health and Aging (GSHA) cohort. Full body images were investigated for melanocytic nevi, seborrheic keratoses, hemangiomas, dermatofibromas, and lentigines. Information on the phenotypic trait, sun exposure, use of sun-protective measures, and history of sunburns was collected in a questionnaire. RESULTS: Common melanocytic nevi were the most frequently encountered skin lesions. Male sex was associated with multiple common nevi on the abdomen and the presence of atypical nevi. High sun exposure in central European latitudes during adolescence was positively associated with multiple common nevi on the total body. Multiple common nevi and atypical nevi on the back correlated with frequent use of sunscreens with SPF during young adulthood and adolescence, respectively. CONCLUSION: Our study adds new knowledge about the most frequently occurring benign skin tumors, considering all visible body areas. This research may serve as a reference basis for following epidemiological studies.

The impact of surgeon's experience and sex on the incidence of cystoid macular edema after uneventful cataract surgery.

PURPOSE: To assess the rate of pseudophakic cystoid macular edema (pCME) in uneventful cataract surgery in surgeons in training vs experienced surgeons and to analyze the rate of pCME according to surgeon's sex. METHODS: Medical reports post phacoemulsification between 2010 and 2018 at the Department of Ophthalmology, Medical University of Graz, Austria, were reviewed for pCME. A running lifetime number of preceding cataract surgeries was used to express hands-on experience. A cut-off number of 300 surgeries was defined to distinguish between surgeons in training and experienced surgeons. Outcome parameters were incidence of pCME, patient's sex and age, laterality of eye, coexistence of pseudoexfoliation syndrome (PEX), duration of surgery and surgeon's sex. RESULTS: 25.422 surgeries on 18.266 patients were included. The majority was performed by experienced surgeons (23.139, 91.0%) vs 2.283 (9.0%) by surgeons in training (25 surgeons, 9 (36%) female and 16 (64%) male). pCME occurred in 32 eyes (1.4%) following surgery by surgeons in training and in 152 eyes (0.7%) following surgery by experienced surgeons. Chance for pCME was 1.57 higher in training surgeries (95% CI 1.03-2.41, p = 0.034) and longer duration (OR = 1.04; 95% CI 1.02-1.07, p = 0.001). After excluding the first 100 surgeries for every surgeon in training similar results were observed. No difference in risk for pCME was found between female and male surgeons in both groups (training and experienced surgeons). CONCLUSION: In conclusion, the rate for pCME after uneventful cataract surgery is significantly higher for surgeons in training but steadily decreasing and associated to surgical time. No difference in the risk for pCME was found between female and male surgeons.

Determining the center of a keratoconus: Comparison of different tomographic parameters and impact of disease severity.

Purpose: There exists remarkable variation in definitions for the location of the center of a keratoconus. The objective of this study was to analyze deviations between locations obtained by different tomographic maps for that purpose. Furthermore, it was investigated whether these deviations are influenced by disease severity. Methods: In 162 eyes with keratoconus, corneal tomographic maps derived by Scheimpflug technology were retrospectively analyzed to determine the cone location with 5 different methods: maximum axial curvature of the front surface (Kmax), maximum tangential curvature of the front surface (tKmax), minimum pachymetry (Pachymin), maximum elevation of the front surface (ELEF), and maximum elevation of the back surface (ELEB). Distances between the locations were calculated and tested for a correlation with keratoconus severity and distance between cone and corneal vertex. Results: Cone locations derived from the curvature maps (Kmax, tKmax) showed the lowest agreement with the locations determined by pachymetry or elevation maps. The largest distances were found between Kmax and Pachymin [Median and Interquartile range: 1.19 mm (0.87, 1.60)], Kmax and ELEB [1.12 mm (0.79, 1.41)], and Kmax and ELEF [0.97 mm (0.64, 1.27)]. Low distances (<0.5 mm) were calculated between ELEB and ELEF, and ELEB and Pachymin. All of the calculated distances between the locations showed a significant negative correlation with keratoconus severity and most of them increased significantly with a more peripheral position of the cone (p < 0.05). Conclusions: There was low consistency between different methods for describing the location of a keratoconus. Curvature-based determinations of the cone center (Kmax, tKmax) showed the highest deviations and should not be used for that purpose. However, the discrepancies between different cone location methods diminished with increasing disease severity and more central position of the cone.

CHANGES OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY PARAMETERS AFTER INTERNAL LIMITING MEMBRANE PEELING COMPARED WITH NONPEELING IN EPIRETINAL MEMBRANE SURGERY.

PURPOSE: To prospectively compare microvascular changes of internal limiting membrane (ILM) peeled and nonpeeled eyes in patients with idiopathic epiretinal membranes using optical coherence tomography angiography. METHODS: Forty-two patients with epiretinal membranes underwent vitrectomy with (n = 22) or without ILM peeling (n = 20). The mean superficial capillary plexus foveal avascular zone area change between preoperative and three-month postoperative readings served as the main outcome measure. Secondary outcome parameters included mean changes in superficial capillary plexus parafoveal vessel density, central foveal thickness, retinal volume, and best-corrected visual acuity. RESULTS: Mean superficial capillary plexus foveal avascular zone area change (µm 2 ) was 59 ± 74 in the ILM nonpeeling group compared with -12 ± 86 in the ILM peeling group ( P = 0.007). Similarly, mean superficial capillary plexus parafoveal vessel density change (%) was higher in the ILM nonpeeling group (ILM nonpeeling 4 ± 4, ILM peeling -2 ± 6, P = 0.003). The mean retinal volume reduction was higher in the ILM peeling group, and this difference also reached statistical significance ( P = 0.036). There were no intergroup differences in mean central foveal thickness change and mean best-corrected visual acuity change ( P = 0.409 and P = 0.440, respectively). Epiretinal membrane/ILM separation was achieved in 23 of 51 patients. CONCLUSION: The macular microvasculature demonstrated more remodeling in the ILM nonpeeling group after three months.

Cohort profile: 'Biomarkers of Personalised Medicine' (BioPersMed): a single-centre prospective observational cohort study in Graz/Austria to evaluate novel biomarkers in cardiovascular and metabolic diseases.

PURPOSE: Accumulating evidence points towards a close relationship between cardiovascular, endocrine and metabolic diseases. The BioPersMed Study (Biomarkers of Personalised Medicine) is a single-centre prospective observational cohort study with repetitive examination of participants in 2-year intervals. The aim is to evaluate the predictive impact of various traditional and novel biomarkers of cardiovascular, endocrine and metabolic pathways in asymptomatic individuals at risk for cardiovascular and/or metabolic disease. PARTICIPANTS: Between 2010 and 2016, we recruited 1022 regional individuals into the study. Subjects aged 45 years or older presenting with at least one traditional cardiovascular risk factor or manifest type 2 diabetes mellitus (T2DM) were enrolled. The mean age of the participants was 57±8 years, 55% were female, 18% had T2DM, 33% suffered from arterial hypertension, 15% were smokers, 42% had hyperlipidaemia, and only 26% were at low cardiovascular risk according to the Framingham 'Systematic COronary Risk Evaluation'. FINDINGS TO DATE: Study procedures during screening and follow-up visits included a physical examination and comprehensive cardiovascular, endocrine, metabolic, ocular and laboratory workup with biobanking of blood and urine samples. The variety of assessed biomarkers allows a full phenotyping of individuals at cardiovascular and metabolic risk. Preliminary data from the cohort and relevant biomarker analyses were already used as control population for genomic studies in local and international research cooperation. FUTURE PLANS: Participants will undergo comprehensive cardiovascular, endocrine and metabolic examinations for the next decades and clinical outcomes will be adjudicated prospectively.

Blindness and visual impairment in Central Europe.

PURPOSE: To assess the prevalence and causes of visual impairment and blindness in a Central European country. The findings may have implications for the planning of further research and development of therapies in order to prevent blindness. SETTING: Department of Ophthalmology, Medical University of Graz, Austria. DESIGN: Retrospective, epidemiological study. METHODS: The database of the Main Confederation of Austrian Social Insurances was searched for patients with visual impairment, legal blindness or deaf-blindness. This database gathers data from patients of all insurance providers in the country who receive care due to visual impairment and blindness. To determine the prevalence of these conditions, the number of all entries recorded in February 2019 was evaluated. Additionally, all new entries between (January 1st,) 2017, and (December 31st,) 2018, were analysed for distinct characteristics, such as sex, the cause of blindness/visual impairment, and age. Since health care allowances can provide a considerable source of income (459.90€-936.90€ per month), good coverage of practically all patients who are blind and visually impaired in the country can be assumed. RESULTS: On February 2nd, 2019, 17,730 patients with visual impairments, blindness or deaf-blindness were registered in Austria, resulting in a prevalence of these diagnoses of 0.2% in the country. During the observational period from 2017 to 2018, 4040 persons met the inclusion criteria. Of these, 2877 were female (65.3%), and 1527 were male (34.7%). The mean age was 75.7 ± 18.0 years (median 82). Most patients (n = 3675, 83.4%) were of retirement age, while 729 (16.6%) were working-age adults or minors. In total, an incidence of 25.0 (95% confidence limit (CL) 24.3-25.8) per 100,000 person-years was observed from 2017 to 2018. A higher incidence was observed for females (32.2, 95% CL 31.0-33.3) than for males (17.7, 95% CL 16.8-18.5). Incidences where higher for males in lower age groups (e.g. 10-14 years: rate ratio RR = 2.7, 95% CL 1.1-6.8), and higher for females in higher age groups (e.g. 70-74 years: RR = 0.6, 95% CL 0.5-0.8). In total, the most frequent diagnoses were macular degeneration (1075 persons, 24.4%), other retinal disorders (493 persons, 11.2%) and inherited retinal and choroidal diseases (IRDs) (186 persons, 4.2%). Persons with IRDs were significantly younger compared to persons with macular degeneration or retinal disorders (IRDs: median 57, range 2-96 vs 83, 5-98 and 82, 1-98 years, p<0.001). For persons of retirement age, macular degeneration, other retinal disorders and glaucoma were the three most frequent diagnoses. In contrast, among working-aged adults and children, IRDs were the leading cause of visual impairment and blindness (103 persons, 14.1%). CONCLUSION: These data show that IRDs are the leading cause of blindness and visual impairment in working-aged persons and children in Austria. Thus, these findings suggest to draw attention to enhance further research in the fields of emerging therapies for IRDs.

ENDOTHELIN-1 AS A RISK FACTOR IN RETINAL VEIN OCCLUSION.

PURPOSE: Retinal vein occlusion (RVO) risk factors largely coincide with cardiovascular risk factors. Endothelin-1 (ET-1), the most potent vasoconstrictor with proinflammatory properties, is a known cardiovascular risk factor. In this study, we explore the role of serum ET-1 as a potential risk factor for RVO. METHODS: Endothelin-1 serum levels were measured in patients with RVO and control subjects. Samples were measured using the sandwich enzyme-linked immunosorbent assay for the quantitative determination of human big endothelin-1 (Biomedica Group, Austria). RESULTS: The study consisted of 147 RVO patients and 150 control subjects. Median serum ET-1 was significantly higher in RVO patients (0.26 pmol/L; range, 0.19-0.37 pmol/L) compared with control subjects (0.10 pmol/L; range, 0.05-0.22 pmol/L) (P < 0.0001) independent of the occlusion site. The difference remained significant after adjusting for arterial hypertension, diabetes mellitus, history of stroke, history of myocardial infarction, history of venous thromboembolism, glomerular filtration rate, and c-reactive protein. CONCLUSION: In conclusion, our results suggest that ET-1 is a potential risk factor for all types of RVO.