Retinopathy of prematurity: a review of risk factors and their clinical significance

The possible effect of pentoxifylline on development and severity of retinopathy of prematurity

BACKGROUND AND AIM

Retinopathy of prematurity (ROP) is the major ocular problem of preterm infants that occurs with abnormal proliferation of immature retinal vessels. Although pentoxifylline (PTX) was reported to inhibit vasculogenesis and neovascularization in experimental studies, there is no clinical data about the effects of PTX treatment on the development and severity of ROP. This clinical study aimed to investigate the possible effects of PTX on the development of ROP.

MATERIALS AND METHODS

A single-centre retrospective study was conducted including preterm infants who were hospitalised in the neonatal intensive care unit between 2015-2017 years. Infants were divided into two groups in terms of PTX administration for adjuvant therapy, as PTX and non-PTX groups.

RESULTS

A total of 211 infants were included in the study [gestational age 29 (27-31) weeks, birth weight 1140 (960-1340) g]. From these, 97 infants (46%) were given PTX treatment. The two groups were similar in terms of demographic data and baseline clinical characteristics. Any stage of ROP was detected in 47.4% of infants in the PTX group, which was significantly higher than those in the non-PTX group (27.2%) (p = 0.002). The incidence of advanced-stage ROP in the PTX group (10.3%) was also higher than in the non-PTX group (2.6%) (p = 0.021). Repeated usage of PTX was not found to be related to the development of ROP (p = 0.059). The time of PTX administration was similar between the ROP and no-ROP groups (median; one vs one week, p = 0.825). Surfactant therapy, duration of hospital stay, and PTX treatment were found as significant risk factors for ROP in the logistic regression analysis.

CONCLUSIONS

In contrast to the experimental studies and also promising results of PTX treatment in some neonatal morbidities, it may be associated with increased incidence and stage of ROP.

Study protocol for a multicentre, open-label, single-arm phase I/II trial to evaluate the safety and efficacy of ripasudil 0.4% eye drops for retinopathy of prematurity

INTRODUCTION

Retinopathy of prematurity (ROP) is a vascular proliferative disorder that occurs in preterm infants. Existing treatments are only indicated in severe ROP cases due to the high invasiveness and the potential risk of irreversible side effects. We previously elucidated that ripasudil, a selective inhibitor of the Rho-associated protein kinase, has the ability to inhibit abnormal retinal neovascularisation in animal models. In addition, ripasudil eye drops (Glanatec ophthalmic solution 0.4%) have been already used for the treatment of glaucoma. Since eye drop therapy is less invasive, early intervention for ROP is possible. The purpose of this phase I/II trial is to evaluate the safety and efficacy of ripasudil eye drops for preterm infants with ROP.

METHODS AND ANALYSIS

This is a multicentre, open-label, single-arm phase I/II trial. To evaluate the safety and efficacy of ripasudil as much as possible, ripasudil will be administered to all enrolled preterm infants with zone I/II, stage 1, or worse ROP. The safety and efficacy of ripasudil in treated patients will be assessed in comparison to a historical control group. Because this is the first trial of ripasudil in preterm infants, a dose-escalation study (once daily for 1 week, then two times per day for 2 weeks) will be conducted in phase I. After obtaining approval from the independent data and safety monitoring board to continue the trial after the completion of phase I, phase II will be conducted. In phase II, ripasudil eye drops will be administered two times per day for 12 weeks. The primary endpoint in phase II is also safety. Efficacy and pharmacokinetics will be evaluated as secondary endpoints.

ETHICS AND DISSEMINATION

This study protocol was approved by the institutional review board at each of the participating centres. Data will be presented at international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBERS

NCT04621136 and jRCT2071200047.

Early Postnatal Oxygen Exposure Predicts Choroidal Thinning in Neonates

Purpose

To evaluate whether choroidal thickness (CT) using arm-mounted optical coherence tomography (OCT) in infants screened for retinopathy of prematurity (ROP) correlates with oxygen exposure in neonates.

Methods

OCT images were obtained in infants screened for ROP in a single level IV neonatal intensive care unit. CT was measured at three different locations: the subfoveal center and 1.5 mm from the fovea center in each direction. Correlation and regression analyses were performed to determine the relationship between clinical factors and CT. Clinical factors included gestational age, birth weight, presence of bronchopulmonary dysplasia (BPD), and fraction of inspired oxygen (FiO₂) at defined time points: 30 weeks postmenstrual age (PMA), 36 weeks PMA, and on day of imaging.

Results

Mean subfoveal, nasal, and temporal choroidal thicknesses CT (SFCT, NCT, and TCT, respectively) were 228.0 ± 51.4 µm, 179.7 ± 50.3 µm, and 186.4 ± 43.8 µm, respectively. SFCT was found to be significantly thicker than NCT and TCT (P < 0.0001 and P = 0.0002, respectively), but no significant difference was found between NCT and TCT (P = 0.547). Compared with infants without BPD, infants with BPD had thinner SFCT and NCT (P = 0.01 and P = 0.0008, respectively). Birth weight was positively correlated with SFCT (r = 0.39, P = 0.01) and NCT (r = 0.33, P = 0.045) but not TCT. Gestational age and ROP stage were not significantly associated with CT. SFCT was found to be significantly thinner with higher average FiO₂ supplementation levels at 30 weeks PMA (r = –0.51, P = 0.01) but not at 36 weeks PMA. Regression analysis revealed that FiO₂ at 30 weeks PMA was an independent predictor of SFCT in infants screened for ROP (P = 0.01).

Conclusions

Early postnatal exposure (<32 weeks PMA) to higher oxygen supplementation in premature neonates statistically predicts choroidal thinning.

Retinopathy prematurity: a systematic review and meta-analysis study based on neonatal and maternal risk factors

BACKGROUND

Retinopathy of prematurity is the abnormal development of retinal arteries in preterm neonates less than 32 weeks and weighing 1500 g, and less, which can lead to visual impairment during life and blindness. This study aims to investigate the relationship between some clinical characteristics of neonates and mothers with Retinopathy of prematurity in the world via a systematic review and meta-analysis.

MATERIALS AND METHODS

The present study is a systematic review and meta-analysis on the relationship between maternal and neonatal clinical variables with Retinopathy of prematurity in the world from the beginning of 2000 to the end of 2020. Accordingly, all English articles published on the topic were searched in scientific databases of Web of Science, PubMed, Google Scholar, Science Direct, and Scopus. The articles were searched independently by two researchers. Statistical analysis of data was performed using fixed and random effects model statistical tests in the meta-analysis, Cochran, meta-regression, I² index, Funnel plot, and Begg's by STATA software program, version 14.

RESULT

A total of 191 studies with a sample size of 140,921 persons were including in the meta-analysis. Accordingly, Preterm delivery ≤28 weeks (OR:6.3, 95% CI:4.9-8.1), Birth Weight ≤1000 g (OR:5.8, 95% CI:4.8-6.8), Birth Weight ≤1500 g (OR:4.8, 95% CI:3.8-6.1), PROM (OR:1.2, 95% CI:1.0-1.4), induced fertility (OR:1.9, 95% CI:1.1-3.0) and Chorioamnionitis (OR:1.5, 95% CI:1.0-2.2) There was a statistically significant association with retinopathy.

CONCLUSION

Based on the results of the present meta-analysis, the risk of retinopathy of prematurity in neonates born at 28 weeks and less, LBW (weight 1500 g and less), neonatal hypotension, chorioamnionitis, and induced fertility increases.

Automatic Staging for Retinopathy of Prematurity With Deep Feature Fusion and Ordinal Classification Strategy

Retinopathy of prematurity (ROP) is a retinal disease which frequently occurs in premature babies with low birth weight and is considered as one of the major preventable causes of childhood blindness. Although automatic and semi-automatic diagnoses of ROP based on fundus image have been researched, most of the previous studies focused on plus disease detection and ROP screening. There are few studies focusing on ROP staging, which is important for the severity evaluation of the disease. To be consistent with clinical 5-level ROP staging, a novel and effective deep neural network based 5-level ROP staging network is proposed, which consists of multi-stream based parallel feature extractor, concatenation based deep feature fuser and clinical practice based ordinal classifier. First, the three-stream parallel framework including ResNet18, DenseNet121 and EfficientNetB2 is proposed as the feature extractor, which can extract rich and diverse high-level features. Second, the features from three streams are deeply fused by concatenation and convolution to generate a more effective and comprehensive feature. Finally, in the classification stage, an ordinal classification strategy is adopted, which can effectively improve the ROP staging performance. The proposed ROP staging network was evaluated with per-image and per-examination strategies. For per-image ROP staging, the proposed method was evaluated on 635 retinal fundus images from 196 examinations, including 303 Normal, 26 Stage 1, 127 Stage 2, 106 Stage 3, 61 Stage 4 and 12 Stage 5, which achieves 0.9055 for weighted recall, 0.9092 for weighted precision, 0.9043 for weighted F1 score, 0.9827 for accuracy with 1 (ACC1) and 0.9786 for Kappa, respectively. While for per-examination ROP staging, 1173 examinations with a 4-fold cross validation strategy were used to evaluate the effectiveness of the proposed method, which prove the validity and advantage of the proposed method.

Hyperoxia Inhibits Proliferation of Retinal Endothelial Cells in a Myc-Dependent Manner

Oxygen supplementation is necessary to prevent mortality in severely premature infants. However, the supraphysiological concentration of oxygen utilized in these infants simultaneously creates retinovascular growth attenuation and vasoobliteration that induces the retinopathy of prematurity. Here, we report that hyperoxia regulates the cell cycle and retinal endothelial cell proliferation in a previously unknown Myc-dependent manner, which contributes to oxygen-induced retinopathy.

Association between postnatal weight gain and need for treatment in retinopathy of prematurity

OBJECTIVE

To study the association between gestational age (GA) and weight at birth and the development of retinopathy of prematurity (ROP), and in particular the link between postnatal weight gain during the first 6 weeks and need for ROP treatment.

MATERIAL AND METHODS

Retrospective observational study of premature infants who underwent ophthalmoscopy at Hospital Universitari Vall d'Hebron in Barcelona, Spain, between June 2017 and December 2018. We collected data on obstetric and birth characteristics, comorbidities, GA and weight at birth, and weekly weight for the first 6 weeks.

RESULTS

Ninety patients with a mean ± SD GA of 26.87 ± 1.90 weeks and a mean birth weight of 884.29 ± 227.40 g were studied. The mean weight at 6 weeks was 1656.89 ± 478.51 g, which corresponds to a gain of 776.17 ± 298.12 g. Thirty-seven patients (41.1%) were diagnosed with ROP and nine (10%) needed treatment. Significant predictors of the need for treatment in patients with ROP were GA (p = .018) and weight at 6 weeks (p = .021). Birth weight was not significant (p = .361).

CONCLUSIONS

GA and weight gain during the first 6 weeks of life are significantly associated with the need for treatment in infants with ROP. Sex and birth weight were not significant predictors. Postnatal weight gain at 6 weeks is predictive of the need for ROP treatment.

Clinical features of premature twin babies with intersibling asymmetry of retinopathy of prematurity severity

OBJECTIVE

To report the clinical features of premature twin babies showing intersibling asymmetry in their severity of retinopathy of prematurity (ROP) and analyze risk factors associated with development of severe ROP between twin siblings with discordant ROP severity.

METHODS

A retrospective study of records of 105 premature twin pairs was conducted. The criteria for discordant ROP with an intersibling difference in ROP severity were as follows: (i) two or more stages of difference in ROP between siblings, (ii) one sibling having treatment-requiring ROP and the other having no ROP or ROP that regressed spontaneously, or (iii) one sibling having aggressive posterior ROP and the other having staged or no ROP. Twin siblings were classified into two groups according to the severity of ROP (no or less ROP and more severe ROP). We examined ocular features in twins having intersibling asymmetry of ROP and analyzed perinatal risk factors for ROP.

RESULTS

Of 105 twin pairs, 32 pairs (30.5%) showed intersibling asymmetry of ROP severity, and 15 pairs (14.3%) showed ROP asymmetry in terms of need for ROP treatment. The development of more severe ROP was associated with longer duration of oxygen supplementation and greater frequency of total blood and packed red blood cell transfusion (p = 0.020, p = 0.045, and p = 0.036, respectively). Longer duration of oxygen supplementation remained a statistically independent risk factor of severe ROP using multivariate logistic regression analysis.

CONCLUSIONS

Ophthalmologists caring for premature infants should be aware of the variable courses and progressions of ROP between twin babies. Longer duration of oxygen supplementation and greater frequency of blood transfusions were associated with higher ROP severity in twins.

Severe Retinopathy of Prematurity Is Not Independently Associated With Worse Neurodevelopmental Outcomes in Preterm Neonates

Purpose: To evaluate the relationship between retinopathy of prematurity (ROP) severity and neurodevelopmental outcomes in premature neonates at 0-36 months corrected age. Methods: A retrospective chart review was performed on 228 neonates screened for ROP at the UCLA Mattel Children's Hospital between 2011 and 2018. Demographic information, clinical outcomes, ROP severity (no ROP, type 1 ROP, type 2 ROP), and Bayley-III neurodevelopmental scores were collected. Infants were grouped into corrected age cohorts (0-12, 12-24, and 24-36 months) to assess neurodevelopmental outcomes with increasing age. Within each age cohort, ANOVA and Chi-Square testing were used to detect differences in birth characteristics and neurodevelopmental scores between infants with type 1 ROP, type 2 ROP, or no ROP. Univariable analyses assessed the relationship between ROP severity and neurodevelopmental outcomes within each age cohort. A multivariable analysis was then performed to determine if ROP severity remained significantly associated with worse neurodevelopmental scores after controlling for birth weight (BW), intraventricular hemorrhage grade (IVH), health insurance type, male sex, and age at Bayley testing. Results: Without controlling for factors associated with prematurity, neonates with type 1 ROP had poorer cognition (p = 0.001) and motor (p = 0.006) scores at ages 0-12 months and poorer cognition (p = 0.01), language (p = 0.04) and motor (p = 0.04) scores at ages 12-24 months than infants without ROP, but no significant differences were detected at ages 24-36 months. After adjusting for BW, IVH, insurance type, male sex, and age at Bayley testing, ROP severity was no longer associated with worse neurodevelopmental scores in any domain. Conclusion: This study emphasizes that poorer neurodevelopmental outcomes in preterm neonates are most likely related to lower birthweight, associated co-morbidities of prematurity, and socioeconomic factors such as health insurance, not severity of ROP itself.

Laser photocoagulation for the treatment of bilateral late-onset retinopathy of prematurity-related retinal detachment in an adult male: A case report

RATIONALE

Retinopathy of prematurity (ROP) is one of the major leading causes of childhood visual morbidity worldwide. Retinal break and traction develop in regressed ROP can further result in rhegmatogenous or tractional retinal detachment years or even decades later.

PATIENT CONCERNS

Here, we reported a case of bilateral ROP related late complication in a 36-year-old male with a chief complaint of increased floaters in his left eye.

DIAGNOSES

The fundus examination showed demarcation lines over temporal side in both eyes with tractional retinal detachment and retinal breaks anterior to the lines. A diagnosis of ROP-related late complication of combined tractional and rhegmatogenous retinal detachment was made.

INTERVENTIONS

Peripheral laser photocoagulation along the demarcation lines for confining the detachment area in both eyes was performed with a stable condition during follow up.

OUTCOMES

After laser retinopexy, the patient was followed up at one week and four months later with stable laser scars and without progression of the retinal detachments.

CONCLUSION

Regressed ROP-associated retinal detachment can occur at any time during life. Special care and follow-up may be necessary for these patients.

Noninvasive ventilation for respiratory distress syndrome is a potential risk factor for retinopathy of prematurity : Single Slovenian tertiary center study

Retinopathy of prematurity (nROP) among extremely low gestational age newborns (ELGAN) in Slovenia has increased in recent years. At the same time mortality has further decreased and less invasive approaches for treatment of respiratory distress syndrome have been established. With the aim to study the possible association between the incidence of ROP and the duration of noninvasive ventilation, this retrospective study comprised ELGANs born during the first period (2010/2011), when invasive respiratory support was the prevalent method and in the second period (2015/2016), when noninvasive respiratory support was adopted. The results showed that the duration of noninvasive ventilation is a potential risk factor for ROP. Controlling for known risk factors for ROP and then adjusting for gestational age, number of transfusions and fraction of inspired oxygen (FiO₂), the odds of ROP were 1.22 times greater (95% confidence interval, CI 1.01-1.48) with every additional week of noninvasive ventilation (p = 0.03).

Clinical Characteristics of Preterm Neonates with Aggressive Posterior Retinopathy of Prematurity

Purpose

We aimed to identify the risk factors that may predispose preterm neonates to develop aggressive posterior retinopathy of prematurity (APROP).

Methods

This retrospective case control study included 16 infants with APROP in zone 1 or posterior zone 2. Thirty-four gestational age and birth weight-matched controls with stage 2 or less ROP were included. We reviewed medical records on infant birth and postnatal characteristics.

Results

Patients who developed APROP had a significantly longer duration of caffeine therapy, were significantly more likely to be small for gestational age (SGA), and were more likely to have a positive blood culture than patients who developed less severe ROP. Patients with APROP who required retreatment had received inotropes for a longer duration of time, had received more plasma transfusions, were more likely to have IVH, and had a greater decrease in the serum hemoglobin during hospitalization.

Conclusion

Being SGA, receiving caffeine for a longer duration, and having culture-proven sepsis were associated with APROP. IVH, a low serum hemoglobin, the need for more plasma transfusions, and a longer duration of inotropes were associated with APROP which required retreatment.

Validation of the DIGIROP-birth model in a Chinese cohort

Background

We aimed to validate the predictive performance of the DIGIROP-Birth model for identifying treatment-requiring retinopathy of prematurity (TR-ROP) in Chinese preterm infants to evaluate its generalizability across countries and races.

Methods

We retrospectively reviewed the medical records of preterm infants who were screened for retinopathy of prematurity (ROP) in a single Chinese hospital between June 2015 and August 2020. The predictive performance of the model for TR-ROP was assessed through the construction of a receiver-operating characteristic (ROC) curve and calculating the areas under the ROC curve (AUC), sensitivity, specificity, and positive and negative predictive values.

Results

Four hundred and forty-two infants (mean (SD) gestational age = 28.8 (1.3) weeks; mean (SD) birth weight = 1237.0 (236.9) g; 64.7% males) were included in the study. Analyses showed that the DIGIROP-Birth model demonstrated less satisfactory performance than previously reported in identifying infants with TR-ROP, with an area under the receiver-operating characteristic curve of 0.634 (95% confidence interval = 0.564–0.705). With a cutoff value of 0.0084, the DIGIROP-Birth model showed a sensitivity of 48/93 (51.6%), which increased to 89/93 (95.7%) after modification with the addition of postnatal risk factors. In infants with a gestational age < 28 weeks or birth weight < 1000 g, the DIGIROP-Birth model exhibited sensitivities of 36/39 (92.3%) and 20/23 (87.0%), respectively.

Conclusions

Although the predictive performance was less satisfactory in China than in developed countries, modification of the DIGIROP-Birth model with postnatal risk factors shows promise in improving its efficacy for TR-ROP. The model may also be effective in infants with a younger gestational age or with an extremely low birth weight.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01952-0.

Use of an online screening algorithm - Weight, Insulin-derived growth factor 1, Neonatal Retinopathy of Prematurity (WINROP) for predicting retinopathy of prematurity in Indian preterm babies

Purpose:

Inopathy of prematurity (WINROP) Weight, insulin-derived growth factor 1, neonatal ROP algorithm is an online tool that has been validated as a predictor of retinopathy of prematurity (ROP) in various countries. The current study was designed to evaluate the predictive ability of WINROP algorithm (http://winrop.com) using postnatal weight gain in detecting Type 1 ROP in Indian babies.

Methods:

Prospective single centre observational study of 153 consecutive preterm babies who were eligible for screening for ROP as per the standard guidelines. Sixteen babies were excluded from the study because of various reasons. Thirty-five babies had gestational age ≥32 weeks and were ineligible for WINROP algorithm. Online WINROP algorithm was used for 102 babies with gestation at birth less than 32 weeks. The alarms triggered by WINROP were documented.

Results:

Laser treatment was done in 30 babies who developed Type 1 ROP. Of these, WINROP alarm was signaled in 24 babies and 6 babies developed ROP without any WINROP alarm. These babies had associated comorbidities like respiratory distress syndrome, patent ductus arteriosus, bacterial sepsis, and ventilatory support. WINROP alarm was significantly associated with Type 1 ROP (P < 0.001). The sensitivity of WINROP was 80% and specificity was 80.6% with a positive predictive value of 63.2% and negative predictive value of 90.6% in detecting Type 1 ROP. In the present study, no baby who was ineligible for WINROP developed Type 1 ROP.

Conclusion:

WINROP provides a novel online monitoring screening tool for identifying babies at risk of developing Type 1 ROP. In our cohort, none of the babies whose period of gestation was more than or equal to 32 weeks developed sight threatening Type 1 ROP. WINROP algorithm may also be useful in Indian population.

Incidence and Risk Factors Associated with Retinopathy of Prematurity in Peru

Purpose

The purpose of this research is to determine retinopathy of prematurity (ROP) prevalence and possible risk factors associated with ROP development in newborns admitted to a neonatal unit of a Peruvian National Reference Hospital.

Patients and Methods

This retrospective study included 216 preterm infants. The data were collected between January 2016 and December 2018. All infants were examined according to Peruvian guidelines for screening and treatment of ROP. The association of clinical risk factors and the development of ROP was analyzed and predictive factors were determined.

Results

The study subjects were 216 preterm infants of which 72 had some stage of ROP (32 stage 1; 23 stage 2 and 17 stage 3) and 144 preterm infants without ROP. The incidence of ROP in preterm infants less than 32 weeks was 60.9%, while for those weighing less than 1500 g it was 71.6%. The factors associated with ROP were gestational age below 32 weeks, birth weight below 1500 grams, neonatal sepsis, oxygen therapy, mechanical ventilation, hyaline membrane disease, bronchopulmonary dysplasia, persistence of ductus arteriosus and intraventricular hemorrhage. Exclusive breastfeeding was found to play a protective role against ROP. Binary logistic regression analysis found that only gestational age below 32 weeks (OR, 2.637; 95% CI, 1.04–6.69), weight below 1500 grams (OR, 4.377; 95% CI, 1.75–10.92), neonatal sepsis (OR, 6.517; 95% CI, 2.81–15.14), vaginal delivery (OR, 3.748; 95% CI: 1.54–9.14), and the presence of hyaline membrane disease (OR, 3.58; 95% CI, 1.47–8.74) are predictors of ROP.

Conclusion

The incidence of ROP among very low birth weight infants was 71.6%. Infants with weight below 1500 grams, neonatal sepsis, presence of hyaline membrane disease whose mother had vaginal delivery are at risk for the development of ROP. Thus, preventing premature births and encouraging exclusive breastfeeding are two main ways to prevent ROP.

Congenital ocular toxoplasmosis with torpedo maculopathy and retinopathy of prematurity in a premature baby

Purpose

To report an unusual case of congenital bilateral abnormality due to coexisting ocular toxoplasmosis and retinopathy of prematurity.

Observations

A prematurely born baby with bilateral retinopathy of prematurity (ROP) (one eye treated) was found to have a hyperpigmented torpedo maculopathy lesion in one eye while the other eye presented with microphthalmia, congenital cataract and non-specific pigmentary retinopathy. Following negative TORCH screening, laboratory tests subsequently revealed increased plasma IgG and IgM for toxoplasmosis.

Conclusions

We present an unusual case of coexistence of congenital ocular toxoplasmosis with torpedo maculopathy and retinopathy of prematurity.

Development and validation of a new clinical decision support tool to optimize screening for retinopathy of prematurity

BACKGROUND/AIMS

Prematurely born infants undergo costly, stressful eye examinations to uncover the small fraction with retinopathy of prematurity (ROP) that needs treatment to prevent blindness. The aim was to develop a prediction tool (DIGIROP-Screen) with 100% sensitivity and high specificity to safely reduce screening of those infants not needing treatment. DIGIROP-Screen was compared with four other ROP models based on longitudinal weights.

METHODS

Data, including infants born at 24-30 weeks of gestational age (GA), for DIGIROP-Screen development (DevGroup, N=6991) originate from the Swedish National Registry for ROP. Three international cohorts comprised the external validation groups (ValGroups, N=1241). Multivariable logistic regressions, over postnatal ages (PNAs) 6-14 weeks, were validated. Predictors were birth characteristics, status and age at first diagnosed ROP and essential interactions.

RESULTS

ROP treatment was required in 287 (4.1%)/6991 infants in DevGroup and 49 (3.9%)/1241 in ValGroups. To allow 100% sensitivity in DevGroup, specificity at birth was 53.1% and cumulatively 60.5% at PNA 8 weeks. Applying the same cut-offs in ValGroups, specificities were similar (46.3% and 53.5%). One infant with severe malformations in ValGroups was incorrectly classified as not needing screening. For all other infants, at PNA 6-14 weeks, sensitivity was 100%. In other published models, sensitivity ranged from 88.5% to 100% and specificity ranged from 9.6% to 45.2%.

CONCLUSIONS

DIGIROP-Screen, a clinical decision support tool using readily available birth and ROP screening data for infants born GA 24-30 weeks, in the European and North American populations tested can safely identify infants not needing ROP screening. DIGIROP-Screen had equal or higher sensitivity and specificity compared with other models. DIGIROP-Screen should be tested in any new cohort for validation and if not validated it can be modified using the same statistical approaches applied to a specific clinical setting.

Stable incidence but regional differences in retinopathy of prematurity in Norway from 2009 to 2017

PURPOSE

To explore the changes over time and regional differences in the incidence of retinopathy of prematurity (ROP) in a national cohort of infants born <28 weeks' gestational age (GA).

METHODS

A population-based study of infants with GA <28 weeks in Norway from 2009 to 2017. Prospectively collected data on clinical variables and outcomes were obtained from the Norwegian Neonatal Network.

RESULTS

Of 1499 live-born infants transferred to a neonatal intensive care unit, 1156 were discharged alive. Four-hundred and fifty-eight infants (39.6%) had ROP, 152 (13.1%) had severe ROP, and 110 (9.5%) were treated for ROP. Eleven hundred infants (95.2%) had complete data sets. In a model comprising region of primary care, GA [odds ratios (OR): 0.65; 95% CI: 0.55-0.77], growth velocity (OR: 1.10; 95% CI: 1.00-2.00), medically treated patent ductus arteriosus (OR: 1.80; 95% CI: 1.19-2.72), weeks of supplemental oxygen (OR: 1.07; 95% CI: 1.03 to 1.11) and region of primary care (OR: 4.95; 95% CI: 3.05-8.04 for the pair of regions with the highest estimated OR) were significantly associated with severe ROP. Additionally, institutional differences for severe ROP were found, with ORs from 0.41 (95% CI: 0.05-3.23) to 5.36 (95% CI: 3.05-9.43) using the largest institution as reference. Incidences were stable over time after adjusting for GA. A larger proportion was treated with anti-vascular endothelial growth factor after 2011.

CONCLUSIONS

The incidence of severe ROP was stable between 2009 and 2017 in Norway. Regional and institutional differences need to be explored in future studies.

Risk Factors Associated with Retinopathy of Prematurity in Very and Extremely Preterm Infants

Background and Objectives: Retinopathy of prematurity (ROP) is the leading cause of blindness in preterm infants. We studied the relationship between different perinatal characteristics, i.e., sex; gestational age (GA); birth weight (BW); C-reactive protein (CRP) and lactate dehydrogenase (LDH) concentrations; ventilation, continuous positive airway pressure (CPAP), and surfactant administration; and the incidence of Stage 1–3 ROP. Materials and Methods: This study included 247 preterm infants with gestational age (GA) < 32 weeks that were successfully screened for ROP. Univariate and multivariate binary analyses were performed to find the most significant risk factors for ROP (Stage 1–3), while multivariate multinomial analysis was used to find the most significant risk factors for specific ROP stages, i.e., Stage 1, 2, and 3. Results: The incidence of ROP (Stage 1–3) was 66.40% (164 infants), while that of Stage 1, 2, and 3 ROP was 15.38% (38 infants), 27.53% (68 infants), and 23.48% (58 infants), respectively. Following univariate analysis, multiple perinatal characteristics, i.e., GA; BW; and ventilation, CPAP, and surfactant administration, were found to be statistically significant risk factors for ROP (p < 0.001). However, in a multivariate model using the same characteristics, only BW and ventilation were significant ROP predictors (p < 0.001 and p < 0.05, respectively). Multivariate multinomial analysis revealed that BW was only significantly correlated with Stage 2 and 3 ROP (p < 0.05 and p < 0.001, respectively), while ventilation was only significantly correlated with Stage 2 ROP (p < 0.05). Conclusions: The results indicate that GA; BW; and the use of ventilation, CPAP, and surfactant were all significant risk factors for ROP (Stage 1–3), but only BW and ventilation were significantly correlated with ROP and specific stages of the disease, namely Stage 2 and 3 ROP and Stage 2 ROP, respectively, in multivariate models.

Perinatal events predicting retinopathy of prematurity in extremely pre-term infants

BACKGROUND

Extremely preterm infants are peculiar in regard to their risk of retinopathy of prematurity (ROP). In this study, we aim to study insults that may affect extremely preterm infants, including prenatal, at birth, and postnatal insults and their effect on the development of ROP.

METHODS

This study used the data from Prematurity and Respiratory Outcomes Program (PROP). All included infants with a gestational age of 23 0/7 to 28 6/7 weeks using best obstetrical estimate. We included stressful events and/or modifiable variables that may affect the normal development. We used multiple regression analysis in our statistical analysis.

RESULTS

We included a total of 751 infants in our study. The mean birth weight for the included sample was 915.1 (±232.94) grams. 391 (52.1%) Infants were diagnosed with ROP. We found a significant negative correlation between ROP development and birth weight (p < 0.001), with a correlation coefficient of - 0.374. We found that the need for prophylactic indomethacin (OR 1.67), the occurrence of air leaks (OR: 2.35), ventilator-associated pneumonia (OR: 2.01), isolated bowel perforations (OR: 3.7), blood culture-proven sepsis (OR: 1.5), other infections (OR: 1.44), and receiving ventricular shunt (OR: 2.9) are significantly associated with the development of ROP.

CONCLUSIONS

We believe this study included the largest number of factors studied in the largest sample of extremely premature infants. We recommend a screening program for extremely preterm infants that takes into account a scoring system with higher scores for complicated condition.

Blindness Secondary to Retinopathy of Prematurity in Sub-Saharan Africa

Purpose: Retinopathy of Prematurity (ROP) has been suggested to be increasing in Africa. However, it was only previously documented as a cause of blindness in 8 of 48 (16.7%) sub-Saharan African countries. The purpose of this study was to better understand the magnitude and breadth of blindness from ROP in sub-Saharan Africa.Methods: A questionnaire was sent to 455 ophthalmologists practicing in sub-Saharan Africa; the questionnaire was available in English, French and Portuguese.Results: Responses were received from 132 of 455 (29%) ophthalmologists to whom the survey was sent. Eighty-three respondents were identified as ROP-involved ophthalmologists and were from 26 of 48 (54%) sub-Saharan African countries. Ophthalmologists in 23 countries reported that they examined at least one child who was blind from ROP during the last 5 years. Sixteen of these countries had not previously reported cases of blindness from ROP in the literature. The perceived occurrence of Type 1 or more severe ROP was reported to be increasing by 31 of 77 (40%) ROP-involved ophthalmologists. ROP-involved pediatric ophthalmologists and retinal surgeons reported the number of infants they examined annually with Type 1 or more severe ROP increased from a median of 1 (range: 0-15) to a median of 4 (range: 0-40) from 2015 to 2019. ROP was estimated to be the cause of blindness for 10% of all blind children examined by ROP-involved pediatric ophthalmologists and retinal surgeons during 2019.Conclusions: ROP is becoming a more important and widespread cause of childhood blindness in sub-Saharan Africa.

GLYCEMIC VARIABILITY IS ASSOCIATED WITH TREATMENT REQUIRING RETINOPATHY OF PREMATURITY: A Case-Control Study

PURPOSE

To assess the association between glycemic variability (GV) and Type 1 retinopathy of prematurity (ROP) in infants with birth weights of less than 1,251 g.

METHODS

A case-control study of infants with birth weights of less than 1,251 g who developed Type 1 ROP (n = 20) was conducted. Controls had a less severe ROP or no eye disease and were individually matched for gestational age and birth weight (n = 40). Odds ratios of ROP were calculated based on multiple factors including oxygen exposure, respiratory support, incidence of hyperglycemia, and GV. For glucose measurements, a continuous glucose monitoring system was used.

RESULTS

There were no significant differences in gender, antenatal steroid administration, severity of illness, and Apgar score. Univariate analyses suggest increased risk for the development of Type 1 ROP based on incidence of intraventricular hemorrhage Grade 3 or 4 (P = 0.048), duration of oxygen exposure (P = 0.003), incidence of hyperglycemia over 150 mg/dL (P = 0.01), and GV according to significantly higher SD (P = 0.002), coefficient of variation (P = 0.001), and mean amplitude of glucose excursion (P = 0.008). Using a multiple regression model, increased risk of Type 1 ROP was only found to be associated with duration of oxygen exposure and higher GV.

CONCLUSION

Our study demonstrates a relationship between GV and the development of severe ROP.

Aggressive posterior retinopathy of prematurity: a review on current understanding

A review of literature was performed, focused on the etiopathogenesis of aggressive posterior retinopathy of prematurity (APROP), the characteristic and atypical clinical features, management strategies, anatomical and visual outcomes. Characteristically APROP has zone I/posterior zone II involvement with prominent plus disease, featureless junction, large vascular loops, flat extra-retinal fibrovascular proliferation, and a rapidly progressive course. The risk factors for APROP are extreme prematurity (birth weight ≤1000 gram and/or gestational age ≤28 weeks), dysregulated oxygen supplementation, intrauterine growth retardation, sepsis, and thrombocytopenia. The uncommon presentations include small zone I disease, a hybrid disease with additional ridge tissue, and APROP in bigger babies with birth weight greater than 1500 g. Laser photocoagulation role is limited by the resultant visual field loss and high refractive error. Although anti-vascular endothelial growth factor injection allows peripheral retinal vascularization; reactivation of disease, systemic absorption of the drug and long-term safety are the chief concerns. Early vitrectomy is required when tractional retinal detachment develops. The visual outcome depends upon the morphology and vascular development of the macula. With the limited yet emerging new understanding of the pathophysiology, a multifaceted rational and individualized treatment strategy is suggested for APROP. Best practices in neonatal intensive care may prevent the occurrence of APROP. Further studies need to be performed for the prevention and safe, effective management of APROP.

Incidence and risk factors of retinopathy of prematurity in an Italian cohort of preterm infants

OBJECTIVE

Non-negligible differences in retinopathy of prematurity (ROP) and its risk factors between different neonatal intensive care units (NICUs) are reported. Our aim was to assess the incidence and risk factors for ROP development in a large cohort of very preterm infants who were assisted in two Italian NICUs.

METHODS

Preterm infants with gestational age between 23+ 0 and 29+ 6 weeks were stratified into subgroups of infants who developed ROP and those who did not; their clinical characteristics were compared with univariate and multivariable logistic regression analyses.

RESULTS

We studied a total of 178 infants of whom 67 (38%) developed ROP (stage 1: n = 12; stage 2: n = 41; stage 3: n = 14). Regression analysis demonstrated that maternal milk (OR 0.979, 95% Cl 0.961-0.998) decreased the risk of developing ROP, while intraventricular hemorrhage (IVH) (OR 2.055, 95% Cl 1.120-3.772) increased it. Moreover, maternal milk was found to decrease (OR 0.981, 95% Cl 0.964-0.997) the risk of ROP at discharge, while RBC transfusion increased it (OR 1.522, 95% Cl 1.208-1.916).

CONCLUSIONS

In our cohort the occurrence of ROP was similar to that previously reported. Strategies for promoting the use of mother's own milk, preventing IVH, and standardizing the approach to RBC transfusions could contribute to decreasing the risk of ROP in very preterm infants.

PFKFB3: A Potential Key to Ocular Angiogenesis

The current treatment for ocular pathological angiogenesis mainly focuses on anti-VEGF signals. This treatment has been confirmed as effective despite the unfavorable side effects and unsatisfactory efficiency. Recently, endothelial cell metabolism, especially glycolysis, has been attracting attention as a potential treatment by an increasing number of researchers. Emerging evidence has shown that regulation of endothelial glycolysis can influence vessel sprouting. This new evidence has raised the potential for novel treatment targets that have been overlooked for a long time. In this review, we discuss the process of endothelial glycolysis as a promising target and consider regulation of the enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase as treatment for ocular pathological angiogenesis.

Incidence, Risk Factors and Screening Evaluation of Retinopathy of Prematurity in High Birthweight Infants: A Large Cohort Study in Turkey

Purpose: To report and evaluate the incidence and risk factors of retinopathy of prematurity (ROP) and to assess the sensitivity and specificity of Turkish national screening guideline (NSG) in heavier infants with a birth weight (BW) of >1500 g.Methods: The data of 1784 preterm infants with BW>1500 g, who were screened between 2009 and 2016 in a university hospital in Turkey, were analyzed retrospectively. The rates of any stage and severe (treatment-requiring) ROP incidence were investigated. The possible protective and risk factors were evaluated with univariate analyses and logistic regression analysis.Results: The rate of any stage ROP was 14.1% (n = 251). Severe ROP was observed in 11 infants (0.6%), and 2 of the infants (0.1%) had a gestational age (GA)>32 weeks, which fell outside of the NSG. In logistic regression analysis, BW, GA, O₂ therapy duration, and exchange transfusion were determined to be independent risk factors (respectively, p < .001, p < .001, P = .055, and P = .033). Furthermore, antenatal steroid therapy was determined to have a highly significant protective effect on ROP development (p < .001). The sensitivity of Turkish NSG in identifying severe ROP increased from 82% to 100% with the inclusion of risk factors in addition to GA and BW.Conclusion: This study shows the presence of severe ROP in mature and heavy infants in Turkey. The positive effect of antenatal steroid use and the negative impact of exchange transfusion have been demonstrated for ROP development in mature infants. Possible risk factors should be evaluated with GA and BW to avoid missing severe ROP.

Identification of candidate genes and pathways in retinopathy of prematurity by whole exome sequencing of preterm infants enriched in phenotypic extremes

Retinopathy of prematurity (ROP) is a vasoproliferative retinal disease affecting premature infants. In addition to prematurity itself and oxygen treatment, genetic factors have been suggested to predispose to ROP. We aimed to identify potentially pathogenic genes and biological pathways associated with ROP by analyzing variants from whole exome sequencing (WES) data of premature infants. As part of a multicenter ROP cohort study, 100 non-Hispanic Caucasian preterm infants enriched in phenotypic extremes were subjected to WES. Gene-based testing was done on coding nonsynonymous variants. Genes showing enrichment of qualifying variants in severe ROP compared to mild or no ROP from gene-based tests with adjustment for gestational age and birth weight were selected for gene set enrichment analysis (GSEA). Mean BW of included infants with pre-plus, type-1 or type 2 ROP including aggressive posterior ROP (n = 58) and mild or no ROP (n = 42) were 744 g and 995 g, respectively. No single genes reached genome-wide significance that could account for a severe phenotype. GSEA identified two significantly associated pathways (smooth endoplasmic reticulum and vitamin C metabolism) after correction for multiple tests. WES of premature infants revealed potential pathways that may be important in the pathogenesis of ROP and in further genetic studies.

How to prevent ROP in preterm infants in Indonesia?

BACKGROUND AND AIMS

Retinopathy of prematurity (ROP) is a severe disease in preterm infants. It is seen more frequently in Low-Middle Income Countries (LMIC) like Indonesia compared to High-Income Countries (HIC). Risk factors for ROP development are -extreme- preterm birth, use of oxygen, neonatal infections, respiratory problems, inadequate nutrition, and blood and exchange transfusions. In this paper, we give an overview of steps that can be taken in LMIC to prevent ROP and provide guidelines for screening and treating ROP.

METHODS

Based on the literature search and data obtained by us in Indonesia's studies, we propose guidelines for the prevention, screening, and treatment of ROP in preterm infants in LMIC.

RESULTS

Prevention of ROP starts before birth with preventing preterm labor, transferring a mother who might deliver <32 weeks to a perinatal center and giving corticosteroids to mothers that might deliver <34 weeks. Newborn resuscitation must be done using room air or, in the case of very preterm infants (<29-32 weeks) by using 30% oxygen. Respiratory problems must be prevented by starting continuous positive airway pressure (CPAP) in all preterm infants <32 weeks and in case of respiratory problems in more mature infants. If needed, the surfactant should be given in a minimally invasive manner, as ROP's lower incidence was found using this technique. The use of oxygen must be strictly regulated with a saturation monitor of 91-95%. Infections must be prevented as much as possible. Both oral and parenteral nutrition should be started in all preterm infants on day one of life with preferably mothers' milk. Blood transfusions can be prevented by reducing the amount of blood needed for laboratory analysis.

DISCUSSION

Preterm babies should be born in facilities able to care for them optimally. The use of oxygen must be strictly regulated. ROP screening is mandatory in infants born <34 weeks, and infants who received supplemental oxygen for a prolonged period. In case of progression of ROP, immediate mandatory treatment is required.

CONCLUSION

Concerted action is needed to reduce the incidence of ROP in LMIC. "STOP - R1O2P3" is an acronym that can help implement standard practices in all neonatal intensive care units in LMIC to prevent development and progression.

Tear Fluid Angiogenic Factors: Potential Noninvasive Biomarkers for Retinopathy of Prematurity Screening in Preterm Infants

Purpose

To determine the status of proangiogenic factors in the tear fluid of preterm infants with and without retinopathy of prematurity (ROP).

Methods

Preterm infants (n = 36) undergoing routine ROP screening included in the prospective study were categorized as No-ROP (n = 13, no ROP at any visits), ROP (if ROP was present at first visit; n = 18), or No-ROP to ROP (no disease at first visit, but developed ROP subsequently; n = 5). Infants with ROP were also grouped as progressing (n = 7) and regressing (n = 16) based on ROP evolution between the first and subsequent visits. Schirmer's strips were used to collect tear fluid and proangiogenic factors (VEGF, angiogenin, soluble vascular cell adhesion molecule, and fractalkine) levels (in picograms per milliliter) in tear fluid were measured by multiplex ELISA.

Results

Lower levels of VEGF (135 ± 69; mean ± standard deviation) and higher levels of angiogenin (6568 ± 4975) were observed in infants with ROP compared with infants without ROP (172.5 ± 54.0; 4139 ± 3909) at the first visit. Significantly lower levels of VEGF were observed in the No-ROP to ROP group compared with the No-ROP and ROP groups. The VEGF and angiogenin levels at the first visit were significantly lower in infants with ROP with progressing disease. Angiogenin levels negatively correlated with birth weight and gestational age in ROP. The area under the curve (AUC) and odds ratio (OR) analysis demonstrated that angiogenin/birth weight (AUC = 0.776; OR, 8.6); angiogenin/gestational age (AUC = 0.706; OR, 7.3) and Angiogenin/VEGF (AUC = 0.806; OR, 14.3) ratios were able to differentiated preterm infants with and without ROP.

Conclusions

The association between angiogenin and ROP suggests its possible role in ROP. The ratio of angiogenin level with birth weight, gestational age, and/or VEGF could serve as a potential noninvasive screening biomarker for ROP.

Decreased Platelet Counts and Serum Levels of VEGF-A, PDGF-BB, and BDNF in Extremely Preterm Infants Developing Severe ROP

INTRODUCTION

Thrombocytopenia has been identified as an independent risk factor for retinopathy of prematurity (ROP), although underlying mechanisms are unknown. In this study, the association of platelet count and serum platelet-derived factors with ROP was investigated.

METHODS

Data for 78 infants born at gestational age (GA) <28 weeks were included. Infants were classified as having no/mild ROP or severe ROP. Serum levels of vascular endothelial growth factor A, platelet-derived growth factor BB, and brain-derived neurotrophic factor were measured in serum samples collected from birth until postmenstrual age (PMA) 40 weeks. Platelet counts were obtained from samples taken for clinical indication.

RESULTS

Postnatal platelet counts and serum concentrations of the 3 growth factors followed the same postnatal pattern, with lower levels in infants developing severe ROP at PMA 32 and 36 weeks (p < 0.05-0.001). With adjustment for GA, low platelet counts and low serum concentrations of all 3 factors at PMA 32 weeks were significantly associated with severe ROP. Serum concentrations of all 3 factors also strongly correlated with platelet count (p < 0.001).

CONCLUSION

In this article, we show that ROP, platelet counts, and specific pro-angiogenic factors correlate. These data suggest that platelet-released factors might be involved in the regulation of retinal and systemic angiogenesis after extremely preterm birth. Further investigations are needed.

Readability, understandability, and quality of retinopathy of prematurity information on the web

BACKGROUND

The purpose of this study is to assess the readability, understandability, and quality of information on retinopathy of prematurity presented at websites frequently visited by parents.

METHODS

A total of 220 websites were assessed, which were recruited by searching for "retinopathy of prematurity" at the Google search engine. The readability of each web page was assessed by Flesch Reading Ease Score, Gobbledygook's Gunning Frequency, Flesch Kincaid Grade Level, Coleman Liau score, The Simple Measure of Gobbledygook, Fry Graph Readability Formula, and Automated readability score. The understandability of the web pages included in the study was measured by using the Patient Education Materials Assessment Tool. Quality was evaluated using Health in Net code and JAMA. The ALEXA traffic tool was used to reference the domains' popularity and visibility.

RESULTS

Sixty-four websites were included to the study. The average Flesch Reading Ease Score was 50.1 ± 11.4, Gunning Frequency of Gobbledygook level was 13.4 ± 2.5, The Flesch-Kincaid Grade level was 10.7 ± 2.2, Coleman Liau level was 10.8 ± 1.7, Simple Measure of Gobbledygook level was 10.0 ± 1.9, and Fry Graph Readability Formula 11.9 ± 2.7, Automated readability score 10.4 ± 2.5. The average understandability score for all website-based patient education materials was 76.9 ± 15.2. Total JAMA Benchmark score is 2.27 ± 1.14 (range from 1 to 4). The quality of information at most websites were determined by our chosen assessments to not to be good.

CONCLUSION

Websites addressed to parents for retinopathy of prematurity had found to have high understandability. It was concluded based on this study that readability and quality of presented written materials at online sources need to be improved.

Retinopathy of Prematurity and Assisted Reproductive Technology: Is There an Association?

Purpose

This study aimed to determine the incidence of retinopathy of prematurity (ROP) and to assess whether assisted reproductive technology (ART) is a risk factor for ROP independent of the generation of multiple births by determining the occurrence and severity of ROP and the need for treatment. We will also evaluate other risk factors associated with the development of ROP among preterm infants.

Patients and Methods

We conducted a retrospective chart review for all premature infants who were screened for ROP according to the screening guidelines of the American Academy of Ophthalmology and born at King Abdulaziz University Hospital from 2015 to 2019. In addition to ophthalmological results, data on gestational age (GA), birth weight (BW), type of pregnancy (singleton or multiple), type of conception (natural or ART), infantile factors, and maternal factors were recorded.

Results

A total of 229 preterm babies met our criteria. The mean GA at birth was 29.35 weeks. Notably, 175 neonates were conceived naturally and 54 were conceived by ART. Furthermore, 33 infants in the natural conception group were products of multiple pregnancies, as were 49 infants in the ART group. ROP was noted in 96 of 229 infants (41.92%). No significant difference was found in the occurrence of ROP between multiple neonates in the natural and ART groups. However, ART birth babies in general were significantly associated with the development of ROP (P=0.045). On multiple regression analysis, early GA, low BW, and extended oxygen therapy were the variables most significantly associated with ROP (P≤0.001).

Conclusion

In our sample, ART in multiple birth babies per se did not seem to be a risk factor for ROP. However, ART babies were more prone to develop ROP than natural conception birth babies, which seemed to be more severe.

Potential Effects of Nutraceuticals in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), the most common cause of childhood blindness, is a hypoxia-induced eye disease characterized by retinal neovascularization. In the normal retina, a well-organized vascular network provides oxygen and nutrients as energy sources to maintain a normal visual function; however, it is disrupted when pathological angiogenesis is induced in ROP patients. Under hypoxia, inadequate oxygen and energy supply lead to oxidative stress and stimulate neovasculature formation as well as affecting the function of photoreceptors. In order to meet the metabolic needs in the developing retina, protection against abnormal vascular formation is one way to manage ROP. Although current treatments provide beneficial effects in reducing the severity of ROP, these invasive therapies may also induce life-long consequences such as systemic structural and functional complications as well as neurodevelopment disruption in the developing infants. Nutritional supplements for the newborns are a novel concept for restoring energy supply by protecting the retinal vasculature and may lead to better ROP management. Nutraceuticals are provided in a non-invasive manner without the developmental side effects associated with current treatments. These nutraceuticals have been investigated through various in vitro and in vivo methods and are indicated to protect retinal vasculature. Here, we reviewed and discussed how the use of these nutraceuticals may be beneficial in ROP prevention and management.

Severe retinopathy of prematurity is associated with early post-natal low platelet count

Pathophysiology of retinopathy of prematurity (ROP) still presents a gap. Lately blood tests parameters of premature infants have been measured at different times of ROP, attempting to detect correlations with ROP development and progression. So far, very early post-natal biomarkers, predictive of ROP outcome, have not been detected. Our purpose is to evaluate, in the earliest post birth blood sample, the correlation between routinely dosed blood parameters and ROP outcome. 563 preterm babies, screened according to ROP guidelines, were included and classified in conformity with ET-ROP study in "Group 1" (ROP needing treatment), "Group 2" (ROP spontaneously regressed) and "noROP" group (never developed ROP). The earliest (within an hour after delivery) blood test parameters routinely dosed in each preterm infant were collected. Platelet count was decreased in Group 1 versus noROP group (p = 0.0416) and in Group 2 versus noROP group (p = 0.1093). The difference of thrombocytopenic infants among groups was statistically significant (p = 0.0071). CRP was higher in noROP versus all ROPs (p = 0.0331). First post-natal blood sample revealed a significant thrombocytopenia in ROP needing treatment, suggesting a role of platelets in the pathophysiology and progression of ROP, possibly considering it as a predictive parameter of ROP evolution.

Risk Factors for Retinopathy of Prematurity in the Netherlands: A Comparison of Two Cohorts

INTRODUCTION

Retinopathy of prematurity (ROP) remains an important cause for preventable blindness. Aside from gestational age (GA) and birth weight, risk factor assessment can be important for determination of infants at risk of (severe) ROP.

METHODS

Prospective, multivariable risk-analysis study (NEDROP-2) was conducted, including all infants born in 2017 in the Netherlands considered eligible for ROP screening by pediatricians. Ophthalmologists provided data of screened infants, which were combined with risk factors from the national perinatal database (Perined). Clinical data and potential risk factors were compared to the first national ROP inventory (NEDROP-1, 2009). During the second period, more strict risk factor-based screening inclusion criteria were applied.

RESULTS

Of 1,287 eligible infants, 933 (72.5%) were screened for ROP and matched with the Perined data. Any ROP was found in 264 infants (28.3% of screened population, 2009: 21.9%) and severe ROP (sROP) (stage ≥3) in 41 infants (4.4%, 2009: 2.1%). The risk for any ROP is decreased with a higher GA (odds ratio [OR] 0.59 and 95% confidence interval [CI] 0.54-0.66) and increased for small for GA (SGA) (1.73, 1.11-2.62), mechanical ventilation >7 days (2.13, 1.35-3.37) and postnatal corticosteroids (2.57, 1.44-4.66). For sROP, significant factors were GA (OR 0.37 and CI 0.27-0.50), SGA (OR 5.65 and CI 2.17-14.92), postnatal corticosteroids (OR 3.81 and CI 1.72-8.40), and perforated necrotizing enterocolitis (OR 7.55 and CI 2.29-24.48).

CONCLUSION

In the Netherlands, sROP was diagnosed more frequently since 2009. No new risk factors for ROP were determined in the present study, apart from those already included in the current screening guideline.

Ten-Year Trend of Retinopathy of Prematurity Among Extremely Preterm Infants in One Neonatal Intensive Care Unit in China

Background: Extremely preterm (EP) infants are at the highest risk of retinopathy of prematurity (ROP). With more EP infants survived in China, recent data of ROP is lacking. The aim of the study is to report the trend of incidence of ROP among EP infants in a large neonatal intensive care unit in China over the past 10-year period, in relation with the overall survival rate and the change of oxygen saturation targets. Methods: This retrospective cohort study enrolled all EP infants born before 28 weeks' gestation and admitted to one of the largest tertiary neonatal intensive care units in China from 2010 to 2019. Data were compared between two time periods according to different oxygen saturation targets: 2010-2014 (P1) with low saturation target and 2015-2019 (P2) with higher target. Results: Of 630 EP infants admitted during the 10 years, 447 (71.0%) infants survived to discharge. The survival rate increased significantly from 61.6% in P1 to 75.8% in P2 (P < 0.05). Of the 472 infants who had ROP data, 318 (67.4%) developed ROP of any stage, 67 (14.2%) developed severe ROP, and 44 (9.3%) received treatment. The incidence of any ROP increased significantly from 51.7% in P1 to 74.3% in P2 (P < 0.05). The incidence of severe ROP increased from 11.0% in P1 to 15.6% in P2, and ROP treatment increased from 6.9% in P1 to 10.4% in P2, but neither reached statistical significance (both P > 0.05). Conclusions: We observed an increasing trend in the incidence of ROP across the 10-year period in one of the largest neonatal care units in China. The increased survival rate and the use of high-target oxygen saturation in the later period may partly explain this trend. Further investigations are needed to improve the care practices and to reduce the incidence of severe ROP.

Retinal vascular tortuosity: Mechanisms and measurements

Retinal vessel tortuosity has been used in the diagnosis and management of different clinical situations. Notwithstanding, basic concepts, standards and tools of measurement, reliable normative data and clinical applications have many gaps or points of divergence. In this review we discuss triggering causes of retinal vessel tortuosity and resources used to assess and quantify it, as well as current limitations.

Quantitative Handheld Swept-Source Optical Coherence Tomography Angiography in Awake Preterm and Full-Term Infants

Purpose

To compare retinal vascular parameters acquired by handheld swept-source optical coherence tomography angiography (SS-OCTA) between nonsedated preterm and full-term infants.

Methods

Preterm and full-term infants at the University of Washington Medical Center were enrolled. Retinal angiograms (nominal size ∼7 × 7 mm²) were obtained at each routine retinopathy of prematurity (ROP) screening session for preterms and once during the first 72 hours of life for full-terms. Macular vessel area density and nonperfusion area were evaluated on the binarized vasculature map in both small (1.5 × 1.5 mm) and large (3 × 3 mm) quadrants. Average vessel diameter and tortuosity values were obtained from each large vessel branch (length >200 µm). All vascular analyses used previously published algorithms.

Results

Handheld SS-OCTA captured 31 of 55 (56%) high-quality volumes on 8 awake preterm infants (gestational age 28 ± 4 weeks, birth weight 891 ± 314 g, postmenstrual age at first imaging session 37 ± 2 weeks) and 48 of 54 (89%) volumes on 12 awake full-term infants (gestational age 39 ± 1 weeks, birth weight 3405 ± 329 g). Signal-to-noise ratio was 5.08 ± 1.52 dB in preterm and 4.90 ± 1.12 dB in full-term infants. Preterm infants had higher mean large vessel tortuosity compared to full-term infants (P = 0.004). The large nasal quadrant vessel area density of infants with stage 3 and/or pre-plus or worse ROP was higher than other preterm infants (P = 0.007).

Conclusions

Although inadequate image quality limited usable imaging sessions, handheld SS-OCTA achieved adequate signal-to-noise ratio in nonsedated infants for quantitative retinal vascular parameter analysis.

Translational Relevance

Large- and small-vessel parameters were associated with prematurity and ROP severity, respectively.

Respiratory Monitoring: Current State of the Art and Future Roads

In this article, we present current methodologies, available technologies, and demands for monitoring various respiratory parameters. We discuss the importance of noninvasive techniques for remote and continuous monitoring and challenges involved in the current "smart and connected health" era. We conducted an extensive literature review on the medical significance of monitoring respiratory vital parameters, along with the current methods and solutions with their respective advantages and disadvantages. We discuss the challenges of developing a noninvasive, wearable, wireless system that continuously monitors respiration parameters and opportunities in the field and then determines the requirements of a state-of-the-art system. Noninvasive techniques provide a significant amount of medical information for a continuous patient monitoring system. Contact methods offer more advantages than non-contact methods; however, reducing the size and power of contact methods is critical for enabling a wearable, wireless medical monitoring system. Continuous and accurate remote monitoring, along with other physiological data, can help caregivers improve the quality of care and allow patients greater freedom outside the hospital. Such monitoring systems could lead to highly tailored treatment plans, shorten patient stays at medical facilities, and reduce the cost of treatment.

Prolactin stimulates the vascularisation of the retina in newborn mice under hyperoxia conditions

The hormone prolactin (PRL) is emerging as an important regulator of ocular blood vessels. PRL is pro-angiogenic and acquires anti-angiogenic properties after undergoing proteolytic cleavage to the PRL fragment, vasoinhibin. The vascularisation of the rodent retina develops after birth when it rapidly expands until completion at the end of the first postnatal week. Exposure of newborn mice to high oxygen levels lowers the rate of blood vessel growth. In the present study, we investigated whether PRL treatment modifies the vascularisation of the retina in newborn mice exposed to high oxygen or to normoxia and whether the retinal conversion of PRL to vasoinhibin may be altered in the neonate. Newborn mice and their nursing mothers were subjected to 75% oxygen or to normoxia from postnatal day (P) 6 to P8 (group 1) or from P2 to P5 (group 2). PRL (2 µg g-1 , i.p., twice a day) or vehicle was injected from P5 to P8 in group 1 and from P1 to P5 in group 2. PRL treatment reduced the retinal inhibition of blood vessel growth and the increase in vascular regression induced by hyperoxia as revealed by immunofluorescence staining of blood vessels and the expression of angiogenesis and apoptosis markers. The pro-angiogenic effect may involve a reduced conversion of PRL to vasoinhibin. Incubation of PRL with retinal extracts showed reduced activity of the PRL-cleaving protease, cathepsin D, in the neonate vs the adult retina that was further reduced under hyperoxia. PRL and the PRL receptor mRNA were expressed at higher levels in the retina at P8 than in the adult, whereas endogenous PRL was undetectable in the circulation at P8. We conclude that PRL has a pro-angiogenic effect in the neonate retina as a result of its reduced conversion to vasoinhibin and that PRL produced by the retina may help promote physiological vascularisation after birth.

Comparison of the detection rates for retinopathy of prematurity (ROP) of the 2013 Philippine Academy of Ophthalmology (PAO) Revised Philippine Guidelines and the 2005 PAO-Philippine Pediatric Society (PPS) Guidelines for ROP screening in the Philippine General Hospital: a 5-year review

Objectives

Compare the detection rates of the 2013 Philippine Academy of Ophthalmology (PAO) guidelines for retinopathy of prematurity (ROP) screening and the 2005 PAO-Philippine Pediatric Society guidelines in identifying infants who develop ROP in the 5-year study period in the Philippine General Hospital (PGH). Secondary objectives include determination of ROP prevalence; correlation of gestational age (GA), birth weight (BW) and other risk factors to ROP; and identification of the most common intervention.

Methods and analysis

Retrospective cross-sectional study of ROP records between 1 December 2013 and 30 November 2018 from the Medical Retina Service of the Department of Ophthalmology and Visual Sciences of the institution was studied. Variables with p value <0.05 were considered significant. STATA V.14 was used for all analysis.

Results

Only 851 of 898 infants screened for ROP were included in the study. Of these 698 would have been screened based on 2005 guidelines. All 118 infants with ROP were identified by both guidelines. Detection rate was higher using the 2005 than the 2013 guidelines (16.9% vs 13.3%, p value=0.0496). ROP prevalence was 9.7%. Among those with ROP, 70% have at least one identified risk factor, topped by sepsis, pneumonia, hyaline membrane disease, blood transfusion and oxygen supplementation. Only 8% required intervention consisting of laser, anti-vascular endothelial growth factor injection, surgery or in combination.

Conclusion

In PGH, no infants with ROP were missed using the 2005 recommendations. There was no added benefit of increasing threshold for BW and GA as recommended by the 2013 PAO guidelines. Screening guidelines should, however, be tailored to institutional needs, requirements and experience.

Risk Calculator for Retinopathy of Prematurity Requiring Treatment

Importance: Vascular delay that occurs early in the development of retinopathy of prematurity (ROP) is a risk factor that can be compensated by ensuring a good rate of retinal vascularization to avoid ROP that requires treatment. Background: The objective of the present study was to determine the association between ROP that requires treatment and risk factors such as the extent of the temporal avascular area of the retina and the number of days of mechanical ventilation (MV). Design: Observational retrospective case-control study. Participants: Two hundred and twenty-eight premature newborns included in the screening protocol for retinopathy of prematurity. Methods: Subjects underwent retinal examination in the 4 and 6th postnatal weeks. Main Outcome Measures: The temporal avascular area was measured in disc diameters (DD), while the MV time was measured in days of treatment. Results: Patients with a longer MV time had a higher risk of treatment (R 2: 24.7, p < 0.0001; increase in risk of 8.1% for each additional day), as did those who showed greater avascular area (R 2: 24.7, p < 0.0001; increase in risk of 111% for each additional DD). An online calculator system and a table are presented for calculating the risk of ROP requiring treatment as a function of these two risk factors. Conclusions and Relevance: The temporal avascular area of the retina and MV time must be taken into account in the first examination of the newborn to predict the need for ROP treatment.

Autism risk linked to prematurity is more accentuated in girls

INTRODUCTION

Prematurity has been identified as a risk factor for Autism Spectrum Disorder (ASD). The link between Autism Spectrum Disorder (ASD) and birth-week has not been strongly evidenced. We evaluated the correlation between the degree of prematurity and the incidence of autism in a cohort of 871 children born prematurely and followed from birth. The cohort was reduced to 416 premature infants born between 2011-2017 who were followed for 2-14 years, and analyzed according to birth week (degree of prematurity), and according to gender.

RESULTS

43 children (10.3%) received a definite diagnosis of ASD. There was a significant correlation between birth week and the risk of ASD, with 22.6% of children diagnosed with ASD when born at 25 weeks, versus 6% of ASD diagnoses at 31 weeks of prematurity. For children born after 32 weeks, the incidence decreased to 8-12.5%. A strong link was found between earlier birth week and increased autism risk; the risk remained elevated during near-term prematurity in boys. A correlation between early birth week and an elevated risk for ASD was seen in all children, but accentuated in females, gradually decreasing as birth week progresses; in males the risk for ASD remains elevated for any birth week.

CONCLUSION

A statistically significant increase in rates of autism was found with each additional week of prematurity. Females drove this direct risk related to degree of prematurity, while males had an elevated risk throughout prematurity weeks, even at near-term. We recommend including ASD screening in follow up of infants born prematurely, at all levels of prematurity.

Automated detection of early-stage ROP using a deep convolutional neural network

BACKGROUND/AIM

To automatically detect and classify the early stages of retinopathy of prematurity (ROP) using a deep convolutional neural network (CNN).

METHODS

This retrospective cross-sectional study was conducted in a referral medical centre in Taiwan. Only premature infants with no ROP, stage 1 ROP or stage 2 ROP were enrolled. Overall, 11 372 retinal fundus images were compiled and split into 10 235 images (90%) for training, 1137 (10%) for validation and 244 for testing. A deep CNN was implemented to classify images according to the ROP stage. Data were collected from December 17, 2013 to May 24, 2019 and analysed from December 2018 to January 2020. The metrics of sensitivity, specificity and area under the receiver operating characteristic curve were adopted to evaluate the performance of the algorithm relative to the reference standard diagnosis.

RESULTS

The model was trained using fivefold cross-validation, yielding an average accuracy of 99.93%±0.03 during training and 92.23%±1.39 during testing. The sensitivity and specificity scores of the model were 96.14%±0.87 and 95.95%±0.48, 91.82%±2.03 and 94.50%±0.71, and 89.81%±1.82 and 98.99%±0.40 when predicting no ROP versus ROP, stage 1 ROP versus no ROP and stage 2 ROP, and stage 2 ROP versus no ROP and stage 1 ROP, respectively.

CONCLUSIONS

The proposed system can accurately differentiate among ROP early stages and has the potential to help ophthalmologists classify ROP at an early stage.

Oxidative Stress Markers and the Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is a leading cause of potentially preventable blindness in low birth weight preterm infants. Several perinatal and postnatal factors contribute to the incomplete maturation of retinal vascularization, leading to oxidative stress damage. Literature data suggest that the lack of equilibrium between pro-oxidants and anti-oxidants plays a key role. In the last decade, there has been an increasing interest in identifying the antecedents of ROP and the relevant pathogenic mechanisms involved. In this context, a panel of biomarkers was investigated in order to achieve early detection of oxidative stress occurrence and to prevent retinal damage. Several nutritional elements have been found to play a relevant role in ROP prevention. At this stage, no conclusive data have been shown to support the usefulness of one biomarker over another. Recently, the Food and Drugs Administration, the European Medicine Agency, and the National Institute of Health proposed a series of criteria in order to promote the inclusion of new biomarkers in perinatal clinical guidelines and daily practice. The aim of the present review is to offer an update on a panel of biomarkers, currently investigated as potential predictors of ROP, highlighting their strengths and weaknesses.

Plasma metabolites in treatment-requiring retinopathy of prematurity: Potential biomarkers identified by metabolomics

Retinopathy of prematurity (ROP) is a potentially blinding condition caused by disruption of retinal vascularization and metabolism. This study aims to identify altered metabolites from plasma in patients with treatment-requiring ROP (TR-ROP) compared with controls. An untargeted metabolomics analysis was performed to reveal the metabolomic profiles of the plasma between TR-ROP patients (n = 38) and age-matched infants (n = 23). The Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to explore the potential signaling pathways of the changed metabolites. Under positive ion mode, a total of 29 metabolites were significantly altered in plasma between TR-ROP patients and controls, and 23 altered metabolites were identified under negative ion mode. KEGG analyses indicated that "protein digestion and absorption" and "aminoacyl-tRNA biosynthesis" were the most enriched pathways of the altered metabolites. These results demonstrated that metabolomic profiles changed in plasma of TR-ROP, and the altered metabolites could be served as potential biomarkers for the diagnosis and prognosis of TR-ROP patients. Besides, the metabolomic profiles might provide clues to discover novel therapeutic strategies in ROP treatment.

Maternal diabetes mellitus as an independent risk factor for clinically significant retinopathy of prematurity severity in neonates less than 1500g

Background

Retinopathy of prematurity (ROP) is a significant morbidity in preterm babies. Multiple risk factors for severe ROP have been extensively studied, however, only a few studies have included maternal diabetes mellitus (MDM) in their assessment. ROP and diabetic retinopathy are both retinal vascular diseases in which there is leakage and/or neovascularization from damaged retinal vessels. Diabetes may affect ROP development; however, there are conflicting results on the association between MDM and ROP.

Objective

To determine if MDM is an independent risk factor for clinically significant ROP (ROP > Stage II) in neonates weighing less than 1500g.

Design/Method

We conducted a retrospective cohort study of neonates weighing <1500g who were delivered or transferred into our institution from 2007 through 2017. Logistic regression was used to analyze the association between severe ROP and MDM. The risks for the different stages of ROP from MDM were compared using chi-square linear trend test.

Results

We extracted 883 paired maternal-neonatal data. The mean (standard deviation) gestational age and birthweight were 28.5 (2.9) weeks and 1052.7 (300.9) grams, respectively. Of the 883 mothers, 72 (8.2%) had DM. The incidence of ROP and severe ROP was 42.4% (374/883) and 6.5% (57/883) respectively. The odds ratio comparing MDM and severe ROP was 3.47 [95% CI: 1.51–7.96]; p<0.01). Compared to Stage I, the risk of MDM in infants with ROP increased from 1.49 in Stage II ROP to 2.59 in Stages III&IV. Severe ROP was associated with infant steroid use (OR: 5.92 [95% CI: 2.83–12.38]; p <0.01), sepsis (OR: 2.13 [95% CI: 1.09–4.14]; p = 0.03) chorioamnionitis (OR: 1.90 [95% CI: 1.03–3.50]; p = 0.04), and maternal steroid use (OR: 0.51 [95% CI: 0.32–0.79]; p<0.01).

Conclusion

Maternal diabetes is associated with ROP and the strength of association increased with increasing severity of ROP.