[Retinopathy of prematurity: from prevention to treatment]

Global Prevalence and Severity of Retinopathy of Prematurity over the Last Four Decades (1985-2021): A Systematic Review and Meta-Analysis

BACKGROUND

Retinopathy of prematurity (ROP) is a vasoproliferative disease of the retina that occurs in premature infants. The prevalence of ROP reported so far is inconsistent.

AIM

To conduct a systematic review to describe the trend of ROP prevalence between 1985 and 2021, and to determine the influence of countries' economic conditions on ROP prevalence.

METHODS

We searched PubMed, Embase, and Google Scholar for studies published between January 1985 and December 2021 using the following MeSH terms: "retinopathy of prematurity", "ROP", "incidence", and "prevalence". Two independent reviewers examined the articles to select studies that met the selection criteria and performed data extraction and study quality assessment. For the meta-analysis, the pooled prevalence was calculated using a random-effects model and R software.

RESULTS

Of 5,250 titles and abstracts, 139 original studies met the inclusion criteria; a total of 121,618 premature infants were included in these studies. The pooled prevalence of ROP was 31.9% (95% confidence interval [CI] 29.0-34.8) and that of severe ROP was 7.5% (6.5-8.7). In general, no significant differences in prevalence were found over the four decades; however, we found a higher prevalence in premature infants ≤28 weeks of gestational age. In addition, the highest ROP prevalence was found in lower-middle-income countries with high mortality rates. In contrast, the highest severe ROP prevalence was found in high-income countries.

CONCLUSION

ROP remains a common cause of morbidity in premature infants worldwide. Therefore, it seems necessary to maintain early identification strategies for patients at higher risk, particularly in low- and middle-income countries.

Insulin-like growth factor-1 and retinopathy of prematurity: A systemic review and meta-analysis

The prevalence of retinopathy of prematurity (ROP) is rapidly increasing worldwide. Many researchers have explored the relationship between insulin-like growth factor-1 (IGF-1) and ROP; however, the results are controversial. This meta-analysis evaluates the correlation between IGF-1 and ROP systematically. We searched for PubMed, Web of Science, Embase, the Cochrane Central Register of Controlled Trials, Ovid MEDLINE, SinoMed, ClinicalTrials.gov, and 3 Chinese databases up to June 2022. Then, the meta-regression and subgroup analysis were carried out. Twelve articles with 912 neonates were included in this meta-analysis. The results revealed that 4 of 7 covariates account for significant heterogeneity: location, measurement method of IGF-1 levels, collection time of blood sample, and the severity of ROP. The pooled analysis showed that low IGF-1 levels could serve as a risk factor associated with the development and severity of ROP. Serum IGF-1 monitoring in preterm infants after birth will be helpful in the diagnosis and treatment of ROP, and the reference value of IGF-1 should be standardized according to the measurement of IGF-1 and the region, as well as the postmenstrual age of prematurity.

[Comparison of the impact of different fat emulsions on clinical outcomes in preterm infants with varying duration of parenteral nutrition: a randomized controlled multicenter study]

OBJECTIVES

To compare the impact of two types of fat emulsion on clinical outcomes in preterm infants with varying duration of parenteral nutrition (PN).

METHODS

Preterm infants meeting the inclusion criteria were randomly assigned to two groups: medium/long-chain triglyceride fat emulsion (referred to as MCT/LCT) group or multi-oil fat emulsion (containing soybean oil, medium-chain triglycerides, olive oil, and fish oil; referred to as SMOF) group. The infants were stratified into groups based on the duration of PN (15-21 days, 22-28 days, and ≥29 days). Clinical characteristics, nutritional status, biochemical indicators, and clinical outcomes were compared between the two groups.

RESULTS

Compared with the MCT/LCT group, the SMOF group had lower peak levels of triglyceride during the hospital stay in preterm infants with PN of 15-21 days, 22-28 days, and ≥29 days, respectively (P<0.05). Logistic regression trend analysis showed that with a longer duration of PN, the risk of parenteral nutrition-associated cholestasis (PNAC) and bronchopulmonary dysplasia (BPD) significantly increased in the MCT/LCT group (P<0.05), while the risk of brain injury did not significantly change (P>0.05). In the SMOF group, the risks of PNAC and BPD did not significantly change with a longer duration of PN (P>0.05), but the risk of brain injury significantly decreased (P=0.006).

CONCLUSIONS

Compared to MCT/LCT, SMOF have better lipid tolerance. With a longer duration of PN, SMOF does not increase the risks of PNAC and BPD and had a protective effect against brain injury. This suggests that in preterm infants requiring long-term PN, the use of SMOF is superior to MCT/LCT.

Bibliometric Analysis of the Top 100 Cited Articles in Pediatric Ophthalmology

PURPOSE

To determine and analyze the 100 most cited articles in pediatric ophthalmology.

METHODS

A literature search was conducted using the ISI Web of Science database on the top 100 most cited articles in pediatric ophthalmology.

RESULTS

The 100 most cited articles were published between 1941 and 2018, with the greatest number published in both 2005 and 2012. A total of 29,731 citations were generated during the study period. There has been a significant increase in citations annually since 1941, with a peak number of citations in 2021 with 2,629 citations. Myopia, retinopathy of prematurity, and other forms of refractive error were the topics most studied and cited in these articles. Most of the articles were classified as either large cohort prospective/retrospective studies (34) or randomized clinical trials (19), with case reports/series being the least frequent (7). Investigative Ophthalmology & Visual Science (23), JAMA Ophthalmology (22), and Ophthalmology (22) published the majority of the articles. Institutions that conducted the majority of the studies presented include the National Eye Institute (10), the Ohio State University College of Optometry (9), and the Oregon Health & Science University (6).

CONCLUSIONS

This bibliometric analysis provides a unique historical perspective of the literature in the field of pediatric ophthalmology that has not been studied before. The research in the field of pediatric ophthalmology is advancing quickly, with most articles and citations occurring within the past 15 years. The strong focus on prospective cohort studies and clinical trials reveals the importance of advancing the treatment of critical disease within the field of pediatric ophthalmology. [J Pediatr Ophthalmol Strabismus. 2023;60(5):330-336.].

Identifying novel candidate compounds for therapeutic strategies in retinopathy of prematurity via computational drug-gene association analysis

Purpose

Retinopathy of prematurity (ROP) is the leading cause of preventable childhood blindness worldwide. Although interventions such as anti-VEGF and laser have high success rates in treating severe ROP, current treatment and preventative strategies still have their limitations. Thus, we aim to identify drugs and chemicals for ROP with comprehensive safety profiles and tolerability using a computational bioinformatics approach.

Methods

We generated a list of genes associated with ROP to date by querying PubMed Gene which draws from animal models, human studies, and genomic studies in the NCBI database. Gene enrichment analysis was performed on the ROP gene list with the ToppGene program which draws from multiple drug-gene interaction databases to predict compounds with significant associations to the ROP gene list. Compounds with significant toxicities or without known clinical indications were filtered out from the final drug list.

Results

The NCBI query identified 47 ROP genes with pharmacologic annotations present in ToppGene. Enrichment analysis revealed multiple drugs and chemical compounds related to the ROP gene list. The top ten most significant compounds associated with ROP include ascorbic acid, simvastatin, acetylcysteine, niacin, castor oil, penicillamine, curcumin, losartan, capsaicin, and metformin. Antioxidants, NSAIDs, antihypertensives, and anti-diabetics are the most common top drug classes derived from this analysis, and many of these compounds have potential to be readily repurposed for ROP as new prevention and treatment strategies.

Conclusion

This bioinformatics analysis creates an unbiased approach for drug discovery by identifying compounds associated to the known genes and pathways of ROP. While predictions from bioinformatic studies require preclinical/clinical studies to validate their results, this technique could certainly guide future investigations for pathologies like ROP.

VEGF Expression in Umbilical Cord MSC Depends on the Patient's Health, the Week of Pregnancy in Which the Delivery Took Place, and the Body Weight of the Newborn - Preliminary Report

Introduction

Cells collected from Wharton's jelly are a rich source of mesenchymal stem cells. They can be easily obtained and grown using the adhesive method. They produce many types of proteins, including VEGF. Their role is to participate in angiogenesis, vasodilation, stimulation of cells to migrate, and chemotactic activity. The aim of this study was to evaluate expression of genes from the vascular endothelial growth factor family: VEGFA, VEGFB and VEGFC in MSC and the analysis of dependence of the expression of the studied genes on clinical factors related to the course of pregnancy and childbirth, and health of mother and child.

Material and Methods

The research material was an umbilical cord obtained from 40 patients hospitalized in the Department of Obstetrics and Pathology of Pregnancy of the Independent Public Clinical Hospital No.1 in Lublin. The age of the women was 21-46, all gave birth by cesarean section. Some of the patients suffered from hypertension and hypothyroidism. Material collected from patients immediately after delivery was subjected to enzymatic digestion with type I collagenase. The isolated cells were then cultured in adherent conditions, and then gene expression was assessed using qPCR and the immunophenotype of the cells was assessed cytometrically.

Results

Conducted studies have shown significant differences in expression of VEGF family genes depending on clinical condition of mother and child. Significant differences in VEGF-family gene expression level in umbilical cord MSC collected from women with hypothyroidism, hypertension, time of labor and birth weight of the baby were shown.

Conclusion

Probably due to hypoxia (caused, for example, by hypothyroidism or hypertension), the MSCs found in the umbilical cord may react with an increased expression of VEGF and a compensatory increase in the amount of secreted factor, the aim of which is, i.a., vasodilation and increase of blood supply to the fetus through the umbilical vessels.

Refractive Changes among Diode Laser-treated Retinopathy of Prematurity Patients: A Retrospective Study

PURPOSE

The purpose of this study was to assess the refractive outcomes of patients who underwent indirect laser photocoagulation for prethreshold type 1 retinopathy of prematurity (ROP) and high-risk type 2 prethreshold ROP in comparison to conservatively managed low-risk prethreshold type 2 ROP.

METHODS

A retrospective analysis was carried out on infants screened for ROP between the years 2015 and 2020. Surviving children who had developed ROP in one or both eyes and received diode laser photocoagulation and those with conservatively managed regressed type 2 ROP who underwent at least one cycloplegic retinoscopy were included in the study.

RESULTS

A total of 144 patients were screened for ROP between 2015 and 2020 at our institution. One hundred and thirty patients (260 eyes) fulfilled the study criteria and were included in this study. The treated group consisted of 132 eyes of 66 infants, of which 38 (14.6%) eyes had prethreshold type 1 ROP while 94 (36.2%) eyes had high-risk prethreshold type 2. The nontreated control group consisted of 128 (49.2%) eyes of 64 infants with low-risk type 2 prethreshold ROP. Earlier prematurity was found to be a significant determinant of the mean change in spherical equivalent among different gestational age groups (P = 0.035). In our cohort, we found that myopia is significantly related to Zone II ROP in comparison to Zone III ROP in the treated eyes (22% vs. 9%) (P = 0.002). No statistically significant difference was found in the final refraction among the treated eyes in relation to the birth weight or stage of prematurity.

CONCLUSION

In the present study, the majority of patients who were treated with diode laser for ROP had favorable anatomical and refractive outcomes. In contrast to previous studies that had suggested a trend toward myopia in laser-treated patients, in our study, the majority (71%) were hyperopes. This study suggests that other factors such as the stage and zone of ROP possibly contribute more to the development of myopia than the laser photocoagulation itself.

Oxidative Stress Implication in Retinal Diseases-A Review

Oxidative stress (OS) refers to an imbalance between free radicals (FRs), namely highly reactive molecules normally generated in our body by several pathways, and intrinsic antioxidant capacity. When FR levels overwhelm intrinsic antioxidant defenses, OS occurs, inducing a series of downstream chemical reactions. Both reactive oxygen species (ROS) and reactive nitrogen species (RNS) are produced by numerous chemical reactions that take place in tissues and organs and are then eliminated by antioxidant molecules. In particular, the scientific literature focuses more on ROS participation in the pathogenesis of diseases than on the role played by RNS. By its very nature, the eye is highly exposed to ultraviolet radiation (UVR), which is directly responsible for increased OS. In this review, we aimed to focus on the retinal damage caused by ROS/RNS and the related retinal pathologies. A deeper understanding of the role of oxidative and nitrosative stress in retinal damage is needed in order to develop targeted therapeutic interventions to slow these pathologies.

Applications and Current Medico-Legal Challenges of Telemedicine in Ophthalmology

BACKGROUND

The digital revolution is redesigning the healthcare model, and telemedicine offers a good example of the best cost-effectiveness ratio. The COVID-19 pandemic has catalysed the use of the telemedicine. The aim of this review is to describe and discuss the role and the main applications of telemedicine in the ophthalmic clinical practice as well as the related medico-legal aspects.

METHODS

45 original articles and 5 reviews focused on this topic and published in English language from 1997 and 2021 were searched on the online databases of Pubmed, Scopus, Web of Sciences and Embase, by using the following key words: "telemedicine", "privacy", "ophthalmology", "COVID-19" and "informed consent".

RESULTS

Telemedicine is able to guarantee patient care using information and communication technologies. Technology creates an opportunity to link doctors with the aim of assessing clinical cases and maintaining high standards of care while performing and saving time as well. Ophthalmology is one of the fields in which telemedicine is most commonly used for patient management.

CONCLUSIONS

Telemedicine offers benefits to patients in terms of saving time and costs and avoiding physical contact; however, it is necessary to point out significant limitations such as the absence of physical examinations, the possibility of transmission failure and potential violations of privacy and confidentiality.

Novel Potential Biomarkers for Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is the main risk factor for vision-threatening disease in premature infants with low birth weight. An accumulating number of independent studies have focused on ROP pathogenesis and have demonstrated that laser photocoagulation therapy and/or anti-VEGF treatment are effective. However, early diagnosis of ROP is still critical. At present, the main method of ROP screening is based on binocular indirect ophthalmoscopy. However, the judgment of whether ROP occurs and whether treatment is necessary depends largely on ophthalmologists with a great deal of experience. Therefore, it is essential to develop a simple, accurate and effective diagnostic method. This review describes recent findings on novel biomarkers for the prediction, diagnosis and prognosis of ROP patients. The novel biomarkers were separated into the following categories: metabolites, cytokines and growth factors, non-coding RNAs, iconography, gut microbiota, oxidative stress biomarkers, and others. Biomarkers with high sensitivity and specificity are urgently needed for the clinical applications of ROP. In addition, using non-invasive or minimally invasive methods to obtain samples is also important. Our review provides an overview of potential biomarkers of ROP.

Cytochrome P450 2J2 inhibits the proliferation and angiogenesis of retinal vascular endothelial cells by regulating the Notch signaling pathway in a hypoxia-induced retinopathy model

Retinopathy of Prematurity (ROP), a type of retinal neovascularization in premature infants, has become a serious problem that drastically affects the quality of life of premature infants. ROP is associated with angiogenesis and neovascularization. Here, we aimed to explain the function and latent roles of Cytochrome P450 2J2 (CYP2J2) in hypoxia-induced retinopathy in retinal vascular endothelial cells (HRVECs). HRVECs were stimulated with hypoxia for 24 h to establish an in vitro retinopathy model. Cell viability and migration were evaluated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and Transwell assays, respectively. Protein and gene expression was determined by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot analysis. We observed that pcDNA3.1(+)-CYP2J2 promoted CYP2J2 and Jagged1 expression, while Dll4 was down-regulated in hypoxia-stimulated HRVECs. Additionally, pcDNA3.1(+)-CYP2J2 inhibited HRVEC viability, reduced PCNA expression, and inhibited the migration of HRVECs. Further, the Notch pathway was inhibited in the Hypoxia+pcDNA3.1(+)-CYP2J2 group. Opposite results were observed upon Terfenadone treatment in hypoxia induced HRVECs. Finally, our findings further verified that DAPT promotes the effects of CYP2J2 on cell viability, migration, and Notch signaling in hypoxia-induced HRVECs, while EDTA reversed the inhibitory effects of CYP2J2 on hypoxia-induced HRVECs. In conclusions, CYP2J2 was found to inhibit the viability and angiogenesis of HRVECs by inhibiting Notch signaling in a hypoxia-induced retinopathy model.