Effect of intraocular lens material and haptic design on anterior capsule contraction after cataract surgery: A systematic review and meta-analysis.

PURPOSE: To compare anterior capsule contraction (ACC) after cataract surgery with implantation of intraocular lens (IOLs) of different materials and designs. METHODS: We searched three electronic databases for relevant studies published up to January 1, 2023. Five randomized controlled trails (RCTs) and three cohort studies involving 1,221 eyes were included in quantitative synthesis. We extracted data, assessed their quality independently, and calculated standard mean difference (SMD) using a random-effects model. Six RCTs and one retrospective cohort were included in information summary. RESULTS: The contraction of the anterior capsule opening area in the hydrophilic group was larger than that of the hydrophobic group from one month to one year postoperatively (P < 0.001 and P < 0.001, respectively). Specifically, the hydrophilic group showed greater contraction of the anterior capsule opening area at one month postoperatively (Standardized mean difference [SMD] = -0.73, 95% confidence interval [CI] = -0.93 to -0.52), three months (SMD = -1.04, 95% CI = -1.32 to -0.75), six months (SMD = -0.99, 95% CI = -1.24 to -0.74) and one year (SMD = -1.33, 95% CI = -2.50 to -0.16). As of one year postoperatively, the anterior capsular opening area showed a trend of decreasing over time in both groups (P = 0.046 and P = 0.050, respectively). In information summary, three studies indicated no relationship between haptic design and ACC, while the other four studies reported that the number and shape of haptic would affect ACC. CONCLUSION: This meta-analysis suggested that the postoperative ACC after the implantation of hydrophobic IOLs was less than that induced by hydrophilic IOLs. Haptic design may also affect the degree of ACC.

RNF217 regulates iron homeostasis through its E3 ubiquitin ligase activity by modulating ferroportin degradation.

Ferroportin (FPN), the body's sole iron exporter, is essential for maintaining systemic iron homeostasis. In response to either increased iron or inflammation, hepatocyte-secreted hepcidin binds to FPN, inducing its internalization and subsequent degradation. However, the E3 ubiquitin ligase that underlies FPN degradation has not been identified. Here, we report the identification and characterization of a novel mechanism involving the RNF217-mediated degradation of FPN. A combination of 2 different E3 screens revealed that the Rnf217 gene is a target of Tet1, mediating the ubiquitination and subsequent degradation of FPN. Interestingly, loss of Tet1 expression causes an accumulation of FPN and an impaired response to iron overload, manifested by increased iron accumulation in the liver together with decreased iron in the spleen and duodenum. Moreover, we found that the degradation and ubiquitination of FPN could be attenuated by mutating RNF217. Finally, using 2 conditional knockout mouse lines, we found that knocking out Rnf217 in macrophages increases splenic iron export by stabilizing FPN, whereas knocking out Rnf217 in intestinal cells appears to increase iron absorption. These findings suggest that the Tet1-RNF217-FPN axis regulates iron homeostasis, revealing new therapeutic targets for FPN-related diseases.

Femtosecond laser-assisted cataract surgery versus conventional phacoemulsification: comparison of internal aberrations and visual quality.

PURPOSE: To compare the internal aberrations and optical quality after femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification cataract surgery (CPCS). METHODS: This study included patients who received FLACS or CPCS from January 2016 to July 2019. Postoperative examinations included wavefront measurements under pupil diameters of 3.0 mm and 5.0 mm, intraocular lens (IOL) decentration, visual acuity (VA), and refractive outcomes. Visual quality was measured with Strehl ratio and modulation transfer function (MTF). Subgroup analyses were conducted based on monofocal or multifocal-extended depth of focus (EDOF) IOL. RESULTS: The study consisted of 221 eyes (105 eyes in FLACS and 116 eyes in CPCS). With a pupil diameter of 5.0 mm, FLACS demonstrated a significantly lower root mean square of total internal aberration (P = 0.004), higher order aberrations (HOAs) (P = 0.034), tilt (P = 0.049), coma (P = 0.004), and spherical aberration (P = 0.014). IOL tilt was found to be positively correlated with total internal aberration (P < 0.001), HOAs (P < 0.001), and coma (P < 0.001). The FLACS group presented significantly smaller IOL decentration than the CPCS group (P < 0.001), but there were no significant differences in terms of VA and refractive outcomes between groups. In the multifocal-EDOF subgroup, Strehl ratio and MTF values were significantly higher in the femtosecond group with a 3.0-mm pupil. CONCLUSION: FLACS induced significantly lower values of IOL tilt, decentration, and internal aberrations compared with the CPCS group with a pupil diameter of 5.0 mm, while no significant differences were found in the VA or optical quality over long-term observation. TRIAL REGISTRATION: This trial was registered at www.chictr.org.cn (registration number ChiCTR2000038965).

Dietary fatty acid intake, plasma fatty acid levels, and the risk of age-related macular degeneration (AMD): a dose-response meta-analysis of prospective cohort studies.

PURPOSE: Previous population studies on the associations between dietary fatty acids (FAs), plasma FAs levels, and the risk of age-related macular degeneration (AMD) have yielded inconclusive results. Herein, we conducted a dose-response meta-analysis to quantitatively evaluate the associations between specific type of dietary FAs, plasma FAs on early and advanced AMD risk. METHODS: PubMed, Web of Science, and EMBASE were systematically searched for observational cohort studies published through May 2020. For highest versus lowest comparison and dose-response analyses, the relative risk (RR) estimates with a 95% confidence interval (CI) were analyzed using random effects model. RESULTS: 11 studies with 167,581 participants were included in the meta-analysis. During the follow-up periods (ranging from 3 to 28 years), 6,318 cases of AMD were recorded. Dietary intake of docosahexaenoic acid (DHA) and eicosatetraenoic acid (EPA) combined (per 1 g/day increment) were found to be negatively associated with early AMD (RR: 0.67, 95% CI [0.51, 0.88]). Each 1 g/day increment of DHA (RR: 0.50, 95% CI [0.32, 0.78]) and EPA (RR: 0.40, 95% CI [0.18, 0.87]) was associated with a 50% and 60% reduction of early AMD risk, respectively. Plasma DHA (RR: 0.72, 95% CI [0.55, 0.95]) and EPA (RR: 0.57, 95% CI [0.40, 0.81]) indicated significant negative relationship with advanced AMD. CONCLUSION: Increasing dietary intake of ω-3 polyunsaturated fatty acids (PUFAs), specifically DHA and EPA, were associated with a reduced risk of early subtype of AMD, while other types of FAs did not present significant results. Further research is warranted to explore the potential association between dietary FA, plasma FA levels, and advanced subtype of AMD.

Collisional and Coulombic unfolding of gas-phase proteins: high correlation to their domain structures in solution.

The three-dimensional structures adopted by proteins are predicated by their many biological functions. Mass spectrometry has played a rapidly expanding role in protein structure discovery, enabling the generation of models for both proteins and their higher-order assemblies. While important coursed-grained insights have been generated, relatively few examples exist where mass spectrometry has been successfully applied to the characterization of protein tertiary structure. Here, we demonstrate that gas-phase unfolding can be used to determine the number of autonomously folded domains within monomeric proteins. Our ion mobility-mass spectrometry data highlight a strong, positive correlation between the number of protein unfolding transitions observed in the gas phase and the number of known domains within a group of sixteen proteins ranging from 8-78 kDa. This correlation and its potential uses for structural biology is discussed.

Subacute-onset cataract in a 29-year-old man with mitochondrial encephalomyopathy: A case report.

This case report aims to emphasize that subacute occurrence of nuclear cataract might be one of the underestimated manifestations of mitochondrial encephalomyopathy, thus periodical ophthalmologic examinations are recommended.

Robotically assisted titration coupled to ion mobility-mass spectrometry reveals the interface structures and analysis parameters critical for multiprotein topology mapping.

Multiprotein complexes have three-dimensional shapes and dynamic functions that impact almost every aspect of biochemistry. Despite this, our ability to rapidly assess the structures of such macromolecules lags significantly behind high-throughput efforts to identify their function, especially in the context of human disease. Here, we describe results obtained by coupling ion mobility-mass spectrometry with automated robotic sampling of different solvent compositions. This combination of technologies has allowed us to explore an extensive set of solution conditions for a group of eight protein homotetramers, representing a broad sample of protein structure and stability space. We find that altering solution ionic strength in concert with dimethylsulfoxide content is sufficient to disrupt the protein-protein interfaces of all of the complexes studied here. Ion mobility measurements captured for both intact assemblies and subcomplexes match expected values from available X-ray structures in all cases save two. For these exceptions, we find that distorted subcomplexes result from extreme disruption conditions, and are accompanied by small shifts in intact tetramers size, thus enabling the removal of distorted subcomplex data in downstream models. Furthermore, we find strong correlations between the relative intensities of disrupted protein tetramers and the relative number and type of interactions present at interfaces as a function of disrupting agent added. In most cases, this correlation appears strong enough to quantify various types of protein interfacial interactions within unknown proteins following appropriate calibration.

Comparative visual outcomes of EDOF intraocular lens with FLACS vs conventional phacoemulsification.

PURPOSE: To investigate the visual quality after femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS) with the implantation of an extended depth-of-focus (EDOF) intraocular lens (IOL) TECNIS Symfony. SETTING: Eye Center, the Second Affiliated Hospital of Zhejiang University, Zhejiang, China. DESIGN: Prospective cohort study. METHODS: Patients were given the option to choose FLACS or CPS and were implanted with a TECNIS Symfony. Main outcome measures were postoperative examinations that included defocus curves, contrast sensitivity (CS), optic path difference aberrometry scan, anterior segment photography, and questionnaires. RESULTS: 261 patients (261 eyes) were enrolled. The circularity index of FLACS was more precise than that of CPS ( P = .001). FLACS demonstrated a significantly lower IOL decentration ( P = .011) and IOL tilt ( P = .009). FLACS presented a significantly lower total aberration ( P < .001), higher-order aberrations (HOAs) ( P = .001), coma ( P = .001), and spherical aberration ( P < .001). With IOL decentration of more than 0.40 mm, total internal aberration ( P = .023) and HOAs ( P = .045) were significantly deteriorated. As for defocus curve, FLACS was better at -1.00 diopter ( P < .01). The FLACS group achieved higher CS at 6 to 18 cycles per degree under glare condition ( P < .05). With regard to photic phenomena, the FLACS group received better outcomes ( P < .05). CONCLUSIONS: With the implantation of an EDOF IOL, FLACS could precisely control the shape and size of the capsulotomy and induce a significantly better-centered IOL, leading to higher visual performance compared with CPS.

Polymer- and lipid-based nanocarriers for ocular drug delivery: Current status and future perspectives.

Ocular diseases seriously affect patients' vision and life quality, with a global morbidity of over 43 million blindness. However, efficient drug delivery to treat ocular diseases, particularly intraocular disorders, remains a huge challenge due to multiple ocular barriers that significantly affect the ultimate therapeutic efficacy of drugs. Recent advances in nanocarrier technology offer a promising opportunity to overcome these barriers by providing enhanced penetration, increased retention, improved solubility, reduced toxicity, prolonged release, and targeted delivery of the loaded drug to the eyes. This review primarily provides an overview of the progress and contemporary applications of nanocarriers, mainly polymer- and lipid-based nanocarriers, in treating various eye diseases, highlighting their value in achieving efficient ocular drug delivery. Additionally, the review covers the ocular barriers and administration routes, as well as the prospective future developments and challenges in the field of nanocarriers for treating ocular diseases.

Ion mobility-mass spectrometry for structural proteomics.

Ion mobility coupled to mass spectrometry has been an important tool in the fields of chemical physics and analytical chemistry for decades, but its potential for interrogating the structure of proteins and multiprotein complexes has only recently begun to be realized. Today, ion mobility-mass spectrometry is often applied to the structural elucidation of protein assemblies that have failed high-throughput crystallization or NMR spectroscopy screens. Here, we highlight the technology, approaches and data that have led to this dramatic shift in use, including emerging trends such as the integration of ion mobility-mass spectrometry data with more classical (e.g., 'bottom-up') proteomics approaches for the rapid structural characterization of protein networks.

The effects of premium intraocular lenses on presbyopia treatments.

Background: Presbyopia has become a global disease affecting the world's aging population. Among various treatments, cataract extraction and intraocular lens (IOL) implantation have become the most popular and common methods of presbyopia correction. During the twentieth century, IOLs have underwent significant innovation and advancements to meet the patients' high demands for functional vision at all distances. Main Text: To meet the increasing needs for excellent near and intermediate vision for daily activities, some premium IOLs with more than one focus have been developed, for example, the refractive MfIOLs, diffractive MfIOLs, extended depth of field (EDOF) IOLs, and accommodating IOLs (AIOLs) were introduced to meet this need. In addition, the add-on MfIOLs have been explored as promising supplementary IOLs for pseudophakic presbyopia. When selecting the MfIOLs, the IOLs' features, patients' characteristics, preoperative eye conditions, and treatment expectations should be considered. Conclusions: In this review, we focus on the multifocal IOLs (MfIOLs) commonly used for presbyopia correction and systematically summarized their optical designs and clinical outcomes. More evidence-based studies are required to provide guidelines for MfIOL selection, provide maximum visual benefits, and develop personalized visual solutions in the future.

Emerging pro-drug and nano-drug strategies for gemcitabine-based cancer therapy.

Gemcitabine has been extensively applied in treating various solid tumors. Nonetheless, the clinical performance of gemcitabine is severely restricted by its unsatisfactory pharmacokinetic parameters and easy deactivation mainly because of its rapid deamination, deficiencies in deoxycytidine kinase (DCK), and alterations in nucleoside transporter. On this account, repeated injections with a high concentration of gemcitabine are adopted, leading to severe systemic toxicity to healthy cells. Accordingly, it is highly crucial to fabricate efficient gemcitabine delivery systems to obtain improved therapeutic efficacy of gemcitabine. A large number of gemcitabine pro-drugs were synthesized by chemical modification of gemcitabine to improve its biostability and bioavailability. Besides, gemcitabine-loaded nano-drugs were prepared to improve the delivery efficiency. In this review article, we introduced different strategies for improving the therapeutic performance of gemcitabine by the fabrication of pro-drugs and nano-drugs. We hope this review will provide new insight into the rational design of gemcitabine-based delivery strategies for enhanced cancer therapy.

Ferrostatin-1-loaded liposome for treatment of corneal alkali burn via targeting ferroptosis.

Alkali burn is a potentially blinding corneal injury. During the progression of alkali burn-induced injury, overwhelmed oxidative stress in the cornea triggers cell damage, including oxidative changes in cellular macromolecules and lipid peroxidation in membranes, leading to impaired corneal transparency, decreased vision, or even blindness. In this study, we identified that ferroptosis, a type of lipid peroxidation-dependent cell death, mediated alkali burn-induced corneal injury. Ferroptosis-targeting therapy protected the cornea from cell damage and neovascularization. However, the specific ferroptosis inhibitor ferrostatin-1 (Fer-1) is hydrophobic and cannot be directly applied in the clinic. Therefore, we developed Fer-1-loaded liposomes (Fer-1-NPs) to improve the bioavailability of Fer-1. Our study demonstrated that Fer-1-NPs exerted remarkable curative effects regarding corneal opacity and neovascularization in vivo. The efficacy was comparable to that of dexamethasone, but without appreciable side effects. The significant suppression of ferroptosis (induced by lipid peroxidation and mitochondria disruption), inflammation, and neovascularization might be the mechanisms underlying the therapeutic effect of Fer-1-NPs. Moreover, the Fer-1-NPs treatment showed no signs of cytotoxicity, hematologic toxicity, or visceral organ damage, which further confirmed the biocompatibility. Overall, Fer-1-NPs provide a new prospect for safe and effective therapy for corneal alkali burn.

Design, synthesis, and biological functionality of a dendrimer-based modular drug delivery platform.

A modular dendrimer-based drug delivery platform was designed to improve upon existing limitations in single dendrimer systems. Using this modular strategy, a biologically active platform containing receptor mediated targeting and fluorescence imaging modules was synthesized by coupling a folic acid (FA) conjugated dendrimer with a fluorescein isothiocyanate (FITC) conjugated dendrimer. The two different dendrimer modules were coupled via the 1,3-dipolar cycloaddition reaction ("click" chemistry) between an alkyne moiety on the surface of the first dendrimer and an azide moiety on the second dendrimer. Two simplified model systems were also synthesized to develop appropriate "click" reaction conditions and aid in spectroscopic assignments. Conjugates were characterized by (1)H NMR spectroscopy and NOESY. The FA-FITC modular platform was evaluated in vitro with a human epithelial cancer cell line (KB) and found to specifically target the overexpressed folic acid receptor.

Characterizing the resolution and accuracy of a second-generation traveling-wave ion mobility separator for biomolecular ions.

High-accuracy, high-resolution ion mobility measurements enable a vast array of important contemporary applications in biological chemistry. With the recent advent of both new, widely available commercial instrumentation and also new calibration datasets tailored for the aforementioned commercial instrumentation, the possibilities for extending such high performance measurements to a diverse set of applications have never been greater. Here, we assess the performance characteristics of a second-generation traveling-wave ion mobility separator, focusing on those figures of merit that lead to making measurements of collision cross-section having both high precision and high accuracy. Through performing a comprehensive survey of instrument parameters and settings, we find instrument conditions for optimized drift time resolution, cross-section resolution, and cross-section accuracy for a range of peptide, protein and multi-protein complex ions. Moreover, the conditions for high accuracy IM results are significantly different from those optimized for separation resolution, indicating that a balance between these two metrics must be attained for traveling wave IM separations of biomolecules. We also assess the effect of ion heating during IM separation on instrument performance.

Comparison of trifocal or hybrid multifocal-extended depth of focus intraocular lenses: a systematic review and meta-analysis.

This meta-analysis aimed to evaluate the clinical outcomes following implantation of trifocal intraocular lenses (IOLs) or a hybrid multifocal-extended depth of focus (EDOF) IOL in cataract or refractive lens exchange surgeries. We examined 13 comparative studies with bilateral implantation of trifocal (898 eyes) or hybrid multifocal-EDOF (624 eyes) IOLs published through 1 March 2020. Better uncorrected and corrected near visual acuity (VA) were observed in the trifocal group (MD: - 0.143, 95% CI: - 0.192 to - 0.010, P < 0.001 and MD: - 0.149, 95% CI: - 0.217 to - 0.082, P < 0.001, respectively), while the hybrid multifocal-EDOF group presented better uncorrected intermediate VA (MD: 0.055, 95% CI: 0.016 to 0.093, P = 0.005). Trifocal IOLs were more likely to achieve spectacle independence at near distance (RR: 1.103, 95% CI: 1.036 to 1.152, P = 0.002). The halo photic effect was generated more frequently by the trifocal IOLs (RR: 1.318, 95% CI: 1.025 to 1.696, P = 0.031). Contrast sensitivity and subjective visual quality yielded comparable results between groups. Trifocal IOLs demonstrated better performance at near distance but apparently led to more photic disturbances. Our findings provided the most up-to-date and comprehensive evidence by comparing the benefits of advanced IOLs in clinical practice.

Outcomes and Prognostic Factors of Posttraumatic Endophthalmitis: A Three-Year Retrospective Study.

PURPOSE: To describe the clinical features, management, and outcomes of patients with posttraumatic endophthalmitis (PTE) and to determine risk factors for poor visual prognosis. METHODS: We retrospectively reviewed the medical records of 42 consecutive patients presenting with PTE who were treated at our institution between 2017 and 2019. Each patient's data, including demographic characteristics, ocular injury details, surgical records, patient outcomes, and laboratory results, were collected and analyzed. Multivariate analysis was conducted to determine the factors associated with poor visual outcomes. RESULTS: In our series, male (n = 36, 85.7%) and patients below 60 years of age (20-40 years, 23.8%; 40-60 years, 57.14%) comprised most of the total cohort. On presentation, 39 (92.8%) of the 42 PTE patients presented best-corrected visual acuity (BCVA) worse than counting fingers. Pars plana vitrectomy (PPV) was performed in all the patients. 59.5% (n = 25) of the patients' BCVA improved after surgery and 33.3% (n = 14) achieved BCVA of 20/200 or better. The rate of evisceration was 7.1% (n = 3). Of the 42 specimens, the culture was positive in 10 (23.8%) eyes. By univariate analysis, factors including sex, occupation, systemic disease, source of trauma, lens injury, silicone oil tamponade, usage of intravitreal antibiotics, BCVA at presentation, and culture positive for any organism did not affect the final visual outcome. The features associated with poor BCVA (grouped as < 20/200 and ≥ 20/200) included older age (P=0.035), corneal-sclera wound (versus sclera wound) (P=0.047), retained intraocular foreign bodies (IOFBs) (P=0.006), treatment > 3 days (versus < 1 day) (P=0.033), and more times of surgeries (P=0.033). CONCLUSIONS: PTE is a severe complication of penetrating globe injuries associated with irreversible visual loss. Our results highlighted the importance of conducting early therapeutic PPV and IOFB removal to achieve better visual outcomes.

Accuracy of Intraocular Lens Power Calculation Formulas in Pediatric Cataract Patients: A Systematic Review and Meta-Analysis.

Background: Among the various intraocular lens (IOL) power calculation formulas available in clinical settings, which one can yield more accurate results is still inconclusive. We performed a meta-analysis to compare the accuracy of the IOL power calculation formulas used for pediatric cataract patients. Methods: Observational cohort studies published through April 2021 were systematically searched in PubMed, Web of Science, and EMBASE databases. For each included study, the mean differences of the mean prediction error and mean absolute prediction error (APE) were analyzed and compared using the random-effects model. Results: Twelve studies involving 1,647 eyes were enrolled in the meta-analysis, and five formulas were compared: Holladay 1, Holladay 2, Hoffer Q, SRK/T, and SRK II. Holladay 1 exhibited the smallest APE (0.97; 95% confidence interval [CI]: 0.92-1.03). For the patients with an axial length (AL) less than 22 mm, SRK/T showed a significantly smaller APE than SRK II (mean difference [MD]: -0.37; 95% CI: -0.63 to -0.12). For the patients younger than 24 months, SRK/T had a significantly smaller APE than Hoffer Q (MD: -0.28; 95% CI: -0.51 to -0.06). For the patients aged 24-60 months, SRK/T presented a significantly smaller APE than Holladay 2 (MD: -0.60; 95% CI: -0.93 to -0.26). Conclusion: Due to the rapid growth and high variability of pediatric eyes, the formulas for IOL calculation should be considered according to clinical parameters such as age and AL. The evidence obtained supported the accuracy and reliability of SRK/T under certain conditions. Systematic Review Registration: PROSPERO, identifier: INPLASY202190077.

Three-Dimensional Heads-up Cataract Surgery Using Femtosecond Laser: Efficiency, Efficacy, Safety, and Medical Education-A Randomized Clinical Trial.

Purpose: To compare the efficiency, efficacy, and safety, as well as the educational value, of heads-up (three-dimensional visualization system-assisted) and traditional microscopic cataract surgery. Methods: This randomized noninferiority trial enrolled 242 eyes of 201 patients who received femtosecond laser-assisted cataract surgery. The questionnaire study enrolled 26 medical interns and 39 medical students. Patients received surgery under either a three-dimensional visualization system (3D group, 117 eyes) or traditional microscope (TM group, 125 eyes) after random allocation. The primary outcome was surgical time. The noninferiority margin of surgical time was 60 seconds. Secondary outcomes included ultrasound power, phacoemulsification time, visual acuity, intraocular pressure, endothelial cell density, central corneal thickness, complications, and observer satisfaction scores for surgical procedures. Results: Surgical time was 462.03 ± 80.36 seconds in the 3D group and 452.13 ± 76.63 seconds in the TM group (difference 9.90 seconds; 95% CI, -9.98 to 29.78; P = 0.365). Visual acuity and other perioperative parameters were comparable between the 3D group and the TM group (all P > 0.05). Incidences of both intraoperative and postoperative complications were low and not statistically different between groups (all P > 0.05). Across all observers, 3D surgery was superior to TM surgery for improving the degree of satisfaction (all P < 0.001). Conclusions: The surgical efficiency of heads-up cataract surgery is not inferior to traditional microscopic surgery. Both methods achieved similar efficacy and safety outcomes. Moreover, heads-up cataract surgery showed a significant advantage in medical education. Translational Relevance: Our findings show that heads-up cataract surgery has comparable efficiency, efficacy, and safety, as well as superior medical educational value, to TM surgery, which lays the foundation for promoting and popularizing this technology.

Ocular manifestations in COVID-19 patients: A systematic review and meta-analysis.

INTRODUCTION: With the accumulating evidence of ocular manifestations of the 2019 novel coronavirus disease (COVID-19), the study aimed to systematically summarize the ocular manifestations in COVID-19 patients. METHODS: The PubMed, EMBASE, Web of Science databases were searched through June 2021. Studies that provided clinical characteristics and outcomes and reported on the ocular manifestations or conjunctival swab RT-PCR tests among COVID-19 patients were included. RESULTS: A total of 30 studies involving 5,717 patients were identified. Ocular manifestations including conjunctival hyperemia (7.6%, 95% confidence interval [CI] 1.8-8.9%), conjunctival discharge (4.8%, 95% CI 1.8-8.9%), epiphora (6.9%, 95% CI 2.8-12.8%), and foreign body sensation (6.9%, 95% CI 2.4-13.0%) were observed. The positive rate of conjunctival swab tests was 3.9% (95% CI 0.2-6.4%). Severe cases of COVID-19 were associated with an increased risk of developing ocular complications (odds ratio [OR] = 2.77, 95% CI 1.75-4.40). CONCLUSIONS: Despite their relatively low incidence rate in COVID-19 patients, ocular manifestations may be non-specific and present as the initial symptoms of infection. The presence of SARS-CoV-2 in the conjunctival swabs implicates the eye as a potential source of infection. Early diagnosis and proper eye protection would help prevent viral transmission.