Acta Ophthalmologica最新文献

Age-related macular degeneration (AMD) is an emerging cause of blindness in aged people worldwide. One of the key signs of AMD is the degeneration of the retinal pigment epithelium (RPE), which is indispensable for the maintenance of the adjacent photoreceptors. Because of impaired energy metabolism resulting from constant light exposure, hypoxia, and oxidative stress, accumulation of drusen in AMD-affected eyes is observed. Drusen contain damaged cellular proteins, lipoprotein particles, lipids and carbohydrates and they are related to impaired protein clearance, inflammation, and extracellular matrix modification. When autophagy, a major cellular proteostasis pathway, is impaired, the accumulations of intracellular lipofuscin and extracellular drusen are detected. As these aggregates grow over time, they finally cause the disorganisation and destruction of the RPE and photoreceptors leading to visual loss. In this review, the role of autophagy in drusen biogenesis is discussed since impairment in removing cellular waste in RPE cells plays a key role in AMD progression. In the future, means which improve intracellular clearance might be of use in AMD therapy to slow the progression of drusen formation.

Purpose: The purpose of this study is to compare the reconstructed corneal power (RCP) by working backwards from the post-implantation spectacle refraction and toric intraocular lens power and to develop the models for mapping preoperative keratometry and total corneal power to RCP.

Methods: Retrospective single-centre study involving 442 eyes treated with a monofocal and trifocal toric IOL (Zeiss TORBI and LISA). Keratometry and total corneal power were measured preoperatively and postoperatively using IOLMaster 700. Feedforward neural network and multilinear regression models were derived to map keratometry and total corneal power vector components (equivalent power EQ and astigmatism components C0 and C45) to the respective RCP components.

Results: Mean preoperative/postoperative C0 for keratometry and total corneal power was -0.14/-0.08 dioptres and -0.30/-0.24 dioptres. All mean C45 components ranged between -0.11 and -0.20 dioptres. With crossvalidation, the neural network and regression models showed comparable results on the test data with a mean squared prediction error of 0.20/0.18 and 0.22/0.22 dioptres² and on the training data the neural network models outperformed the regression models with 0.11/0.12 and 0.22/0.22 dioptres² for predicting RCP from preoperative keratometry/total corneal power.

Conclusions: Based on our dataset, both the feedforward neural network and multilinear regression models showed good precision in predicting the power vector components of RCP from preoperative keratometry or total corneal power. With a similar performance in crossvalidation and a simple implementation in consumer software, we recommend implementation of regression models in clinical practice.

Purpose: To estimate the prevalence of amblyopia and refractive errors among 6-year-old children in Greenland and to assess the impact of incorporating autorefraction, stereoacuity and near visual acuity testing into vision screening.

Methods: In this cross-sectional study, 517 children (238 girls and 279 boys) from 21 locations in Greenland were screened using HOTV charts for distance and near visual acuity (VA), stereoacuity test and non-cycloplegic autorefraction. Referral criteria for further ophthalmological examination included a VA of ≥0.2 logMAR on the worse-seeing eye or an interocular VA difference of ≥2 lines.

Results: Initial screening identified amblyopia (defined as VA of ≥0.3 logMAR) in 7% (unilateral) and 3% (bilateral) of children. However, subsequent ophthalmological examinations confirmed amblyopia in under 40% of referrals. Significant interocular VA differences were found in 9%. The prevalence of refractive errors at the screening was 3% for myopia (≤-0.5 dioptres), 10% for hyperopia (>+2.0 dioptres) and 14% for astigmatism (≤-1.00 dioptres), while the corresponding prevalences at the ophthalmological examination were 4% for myopia, 8% for hyperopia and 6% for astigmatism. Combining screening measurements increased the positive predictive values, thereby enhancing screening accuracy. Specifically, the incorporation of autorefraction or stereoacuity with distance VA demonstrated to be the most effective combination. Six percent of the children were prescribed glasses after the screening procedure.

Conclusion: This study provides the first visual profile of Greenlandic schoolchildren. Incorporating autorefraction, stereoacuity and near visual acuity in vision screenings enhanced the efficacy of detection of vision anomalies. Although this may lead to more false positives, accurate screening is crucial in regions with limited ophthalmological resources.

Purpose: To evaluate whether the intraocular lens (IOL) calculation of the fellow eye (FE) can be used in eyes undergoing combined phacovitrectomy.

Methods: In this retrospective, consecutive case series, we enrolled patients who underwent combined phacovitrectomy with silicone oil removal and IOL implantation at the Goethe-University. Preoperative examinations included biometry (IOLMaster 700; Carl Zeiss). We used the IOL calculation of the FE (FE group) to calculate the prediction error compared with the IOL calculation using only the axial length (AL) of the FE (AL-FE group), as well as using the AL of the operated eye (OE group) in addition to the measurable biometric parameters. IOL calculation was performed using the Barrett Universal II formula. We compared the mean (MAE) and median absolute prediction error (MedAE) with each other. Furthermore, the number of eyes with ±0.50, ±1.00 and ±2.00 dioptres (D) deviation from the target refraction was compared.

Results: In total, 79 eyes of 79 patients were included. MedAE was lowest in the OE group (0.41 D), followed by FE group (1.00 D) and AL-FE group (1.02 D). Comparison between the AL-FE and FE groups showed no statistically significant difference (p = 0.712). Comparing eyes within ±0.50 D of the target refraction, the OE group (63.3%) performed best, followed by the AL-FE group (27.8%) and the FE group (26.6%).

Conclusion: Our results indicate no clinically relevant difference between using the IOL calculation of the FE versus using only the AL of the FE in addition to the measurable parameters for the IOL calculation. A two-step procedure should always be strived for.

Identifying macular neovascularization (MNV) in eyes with central serous chorioretinopathy (CSC) has important implications for its management. Optical coherence tomography angiography (OCTA) is increasingly used for this purpose. Here, we systematically reviewed the literature and conducted meta-analysis to determine the diagnostic accuracy of OCTA for detecting MNV in eyes with CSC. We systematically searched the literature in 12 databases for relevant studies from database inception until 18 November 2023. Eligible studies had eyes with CSC with MNV and CSC without MNV. Index test was OCTA. Reference test was retinal dye angiography. Study selection and data extraction were performed in duplicate, and study was evaluated using the Quality Assessment of Diagnostic Accuracy Studies 2. Our main outcome of interest was the sensitivity and specificity of OCTA for detecting MNV in CSC. Pooled diagnostic test accuracy estimates were computed using MetaDTA. Of 177 records screened, seven fulfilled the eligibility criteria for our study. These studies summarized data from a total of 1061 eyes. Summary estimate sensitivity and specificity to diagnose MNV in eyes with CSC using OCTA was 92.9% (95% CI: 81.7%–97.5%) and 99.4% (95% CI: 84.1%–100.0%), respectively. The main source of bias across studies was the reference standard, as four studies used multimodal imaging including OCTA for the reference standard. OCTA alone is excellent for detecting MNV in CSC compared to retinal dye angiography or multimodal imaging. Using OCTA first before considering retinal dye angiography could potentially save an important number of retinal dye angiographies.

Purpose: To present baseline characteristics and to present the perioperative corneal thickness during corneal crosslinking (CXL) treatment for progressive keratoconus and to describe how the addition of sterile water (SW) efficaciously can maintain the corneal thickness. The treatment efficacy will be evaluated when the 1-year follow-up is complete.

Methods: A randomised clinical study using epithelium-off CXL with continuous UVA irradiation (9 mW/cm²) and two kinds of riboflavin solutions: (i) isoosmolar dextran-based riboflavin (n = 27) and (ii) hypoosmolar dextran-free riboflavin (n = 27).

Inclusion criteria: progressive keratoconus with an increase in maximum keratometry value (Kmax) of 1.0 dioptre (12 months) or 0.5 dioptres (6 months). Corneae thinner than 400 μm were also included.

Outcome parameters: Perioperative corneal thickness and the effect of adding SW.

Results: Seventy-four per cent of the patients in the isoosmolar group and 15% in the hypoosmolar group required the addition of SW, which effectively maintained a corneal thickness of 400 μm in all cases during CXL. The addition of SW was primarily needed during the irradiation procedure and not the preoperative soaking period.

Conclusions: Especially during the CXL irradiation phase, isoosmolar riboflavin causes a significant dehydrating effect leading to corneal thinning during CXL. The customised addition of SW is efficacious in maintaining the corneal thickness during CXL and could increase the safety of the procedure.

Purpose: To evaluate possible risk factors for uveitis among Finnish sarcoidosis patients.

Methods: Patient charts of patients with sarcoidosis, with (n = 97) or without (n = 255) uveitis, and with a comprehensive eye examination from January 2014 to January 2021 at Tays Eye Centre, Tampere University Hospital, Finland were studied.

Results: Sarcoidosis patients with uveitis had higher rate of lymphocytopenia (43% vs. 29%, p = 0.041) and lower serum lysozyme levels (2.0 mg/L vs. 2.3 mg/L, p = 0.049; 95% CI, -0.692 to -0.002). Lysozyme level or lymphocytopenia did not have a statistically significant effect on the probability of uveitis in a binary logistic regression analysis. No other differences in the potential risk factors with p-values ≤0.05 were found, including bilateral hilar lymphadenopathy, serum angiotensin-converting enzyme (ACE) levels, sex, age and history of smoking.

Conclusion: Lymphocytopenia and lower serum lysozyme levels present as possible risk factors for uveitis among patients with sarcoidosis. Systematic measurement of lymphocyte and lysozyme levels in sarcoidosis is needed to further understand their role as potential risk factors.

Purpose: To characterise the retinal vasculometry of a Danish eye and vision cohort and examine associations with systolic blood pressure (BP), diastolic BP, mean arterial BP, and intraocular pressure (IOP).

Design: Longitudinal study.

Methods: The retinal vasculature of fundus images from the FOREVER (Finding Ophthalmic Risks and Evaluating the Value of Eye exams and their predictive Reliability) cohort was analysed using a fully automated image analysis program. Longitudinal associations of retinal vessel morphology at follow-up visit with IOP (baseline and follow-up) and BP (follow-up) were examined using multilevel linear regression models adjusting for age, sex and retinal vasculometry at baseline as fixed effects and person as random effect. Width measurements were additionally adjusted for the spherical equivalent.

Results: A total of 2089 subjects (62% female) with a mean age of 61 (standard deviation 8) years and a mean follow-up period of 4.1 years (SD 0.6 years) were included. The mean arteriolar diameter was approximately 20% thinner than the mean venular diameter, and venules were about 21%-23% less tortuous than arterioles. BP at follow-up was associated with decreased arteriolar diameter from baseline to follow-up. After adjusting for baseline IOP, IOP at follow-up was associated with increased arteriolar tortuosity above baseline (0.59%, 95% CI 0.08-1.10, p-value 0.024).

Conclusion: In a Danish eye and vision cohort, variations in BP and alterations in IOP over time were associated with changes in the width and tortuosity of retinal vessels. Our findings contribute novel insights into retinal vascular alterations over time.

Purpose: To develop and evaluate a photovoltaic, wireless wide-field epiretinal prosthesis for the treatment of retinitis pigmentosa.

Methods: A mosaic array of thinned silicon-based photodiodes with integrated thin-film stimulation electrodes was fabricated with a flexible polyimide substrate film to form a film-based miniaturized electronic system with wireless optical power and signal transmission and integrated electrostimulation. Manufactured implants were characterized with respect to their optoelectronic performance and biocompatibility following DIN EN ISO 10993.

Results: A 14 mm diameter prosthesis containing 1276 pixels with a maximum sensitivity at a near infrared wavelength of 905 nm and maximized stimulation current density 30-50 μm below the electrodes was developed for direct activation of retinal ganglion cells during epiretinal stimulation. Fabricated prostheses demonstrated mucosal tolerance and the preservation of both metabolic activity, proliferation and membrane integrity of human fibroblasts as well as the retinal functions of bovine retinas. Illumination of the prosthesis, which was placed epiretinally on an isolated perfused bovine retina, with infrared light resulted in electrophysiological recordings reminiscent of an a-wave (hyperpolarization) and b-wave (depolarization).

Conclusions: A photovoltaic, wireless wide-field epiretinal prosthesis for the treatment of retinitis pigmentosa using near infrared light for signal transmission was designed, manufactured and its biocompatibility and functionality demonstrated in vitro and ex vivo.