Cerebral Oximetry Monitoring in Extremely Preterm Infants.

BACKGROUND: The use of cerebral oximetry monitoring in the care of extremely preterm infants is increasing. However, evidence that its use improves clinical outcomes is lacking. METHODS: In this randomized, phase 3 trial conducted at 70 sites in 17 countries, we assigned extremely preterm infants (gestational age, <28 weeks), within 6 hours after birth, to receive treatment guided by cerebral oximetry monitoring for the first 72 hours after birth or to receive usual care. The primary outcome was a composite of death or severe brain injury on cerebral ultrasonography at 36 weeks' postmenstrual age. Serious adverse events that were assessed were death, severe brain injury, bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and late-onset sepsis. RESULTS: A total of 1601 infants underwent randomization and 1579 (98.6%) were evaluated for the primary outcome. At 36 weeks' postmenstrual age, death or severe brain injury had occurred in 272 of 772 infants (35.2%) in the cerebral oximetry group, as compared with 274 of 807 infants (34.0%) in the usual-care group (relative risk with cerebral oximetry, 1.03; 95% confidence interval, 0.90 to 1.18; P = 0.64). The incidence of serious adverse events did not differ between the two groups. CONCLUSIONS: In extremely preterm infants, treatment guided by cerebral oximetry monitoring for the first 72 hours after birth was not associated with a lower incidence of death or severe brain injury at 36 weeks' postmenstrual age than usual care. (Funded by the Elsass Foundation and others; SafeBoosC-III ClinicalTrials.gov number, NCT03770741.).

Gut Microbiome and Retinopathy of Prematurity.

Retinopathy of prematurity (ROP), a leading cause of childhood blindness worldwide, is strongly associated with gestational age and weight at birth. Yet, many extremely preterm infants never develop ROP or develop only mild ROP with spontaneous regression. In addition, a myriad of other factors play a role in the retinal pathology, one of which may include the early gut microbiome. The complications associated with early gestational age include dysbiosis of the dynamic neonatal gut microbiome, as evidenced by the development of often concomitant conditions, such as necrotizing enterocolitis. Given this, alongside growing evidence for a gut-retina axis, there is an increasing interest in how the early intestinal environment may play a role in the pathophysiology of ROP. Potential mechanisms include dysregulation of vascular endothelial growth factor and insulin-like growth factor 1. Furthermore, the gut microbiome may be impacted by other known risk factors for ROP, such as intermittent hypoxia and sepsis treated with antibiotics. This mini-review summarizes the literature supporting these proposed avenues, establishing a foundation to guide future studies.

Hyperbilirubinemia and retinopathy of prematurity: a retrospective cohort study.

Retinopathy of prematurity (ROP) is a vasoproliferative retinal disease in preterm infants. Oxidative stress plays a key role in the pathogenesis of ROP. Due to its antioxidant effects, bilirubin has been proposed to be protective against ROP. This study explored the association between hyperbilirubinemia and ROP. We analyzed a 10-year cohort from a neonatal intensive care unit in Milan, Italy, including 1606 infants born under 32 weeks and/or < 1500 g. Data from 1606 infants meeting specific inclusion criteria were reviewed. Eighty infants were excluded due to lack of data, 1526 were deemed eligible for analysis, and 1269 had hyperbilirubinemia requiring phototherapy. There was a higher incidence of ROP among infants with hyperbilirubinemia (13.8%) versus those without (7.8%, p<0.01). Infants with any ROP, non-severe or severe ROP, were exposed to hyperbilirubinemia for a significantly higher number of days compared with those without ROP. Each additional day of exposure increases the risk of developing any ROP by 5%, non-severe ROP by 4%, and severe ROP by 6%. However, this correlation was not observed in infants with gestational age less than 27 weeks and/or body weight less than 1000 g.    Conclusion: Our data show that hyperbilirubinemia requiring phototherapy is associated with an increased risk of developing ROP. However, severe hyperbilirubinemia and ROP share many of their risk factors. Therefore, rather than being a risk factor itself, hyperbilirubinemia may be a surrogate for other risk factors for ROP.    Clinical Trial Registration: NCT05806684. What is Known: • The development of retinopathy of prematurity (ROP) is influenced by several critical risk factors, including low gestational age, low birth weight, supplemental oxygen use, and increased oxidative stress. • In vitro, unconjugated bilirubin is an effective scavenger of harmful oxygen species and a reducing agent, highlighting its potential protective role against oxidative stress. What is New: • Hyperbilirubinemia requiring phototherapy was associated with an increased risk of developing ROP, but this association was not observed in the most vulnerable population of extremely preterm infants. • Every additional day of phototherapy for hyperbilirubinemia increases the risk of ROP by 5% for any ROP, 4% for non-severe ROP, and 6% for severe ROP.

The impact of blood lactic acid levels on retinopathy of prematurity morbidity.

BACKGROUND: Retinopathy of prematurity (ROP) is a common disease in premature infants. In recent years, most researchers have used lactic acid as poor prognosis marker in premature infants. This study aims to explore investigate the impact of blood lactic acid levels on ROP. METHODS: A retrospective case-control study was conducted, and infants with severe ROP born with birth weight (BW) ≤ 1500 g and gestational age (GA) ≤ 32 weeks were enrolled from November 2016 to November 2021. Infants without any stage ROP were included as controls and were matched with ROP infants (1:2) by GA and BW. All selected preterm infants were tested for heel terminal trace blood gas analysis within two weeks of life. Changes in blood lactic acid levels in the two groups were compared and analyzed by using multivariate logistic regression analysis. Sensitivity and specificity were analyzed by receiver operating characteristic (ROC) curve. RESULTS: There were 79 infants in ROP group, and 158 infants in control group. The levels of blood lactic acid were significantly higher in the ROP group on days 1, 3, 5, and 7 compared with control group (all p < 0.05). The blood lactic acid levels on day 5 was an independent risk factor for ROP (p = 0.017). The area under the curve (AUC), sensitivity and specificity were highest on day 5 (AUC 0.716, sensitivity 77.2% and specificity 62.0%, respectively, p < 0.001), and higher on days 1, 3, and 7. CONCLUSION: A high blood lactic acid level in the first seven days of life may be associated with increases ROP occurrence in very preterm infants, and suggest blood lactic acid level may impact the occurrence of ROP.

Insights into Risk: Exploring Retinopathy of Prematurity and Short-term Comorbidities in Moderate-to-Late Preterm Infants.

BACKGROUND: Retinopathy of prematurity (ROP) and short-term comorbidity data moderate-to-late preterm (MLP) infants in Saudi Arabia are limited. AIM: The present study mainly aimed to identify ROP incidence and severity in MLP infants. The secondary objective was to explore whether moderate preterm infants are more prone to systemic short-term comorbidities compared to late preterm infants. MATERIALS AND METHODS: This retrospective study was conducted at King Abdulaziz University Hospital, a tertiary center in Jeddah, Saudi Arabia. Two-hundred and sixty-eight MLP infants born with gestational ages (GAs) of 32 to 36 + 6 weeks were included. Births were classified as moderate preterm (GA 32 to 33 + 6 weeks) and late preterm (GA 34 to 36 + 6 weeks) and the two groups were compared with an independent t-test. RESULTS: ROP incidence was 1.5%; all cases were stage 1 and involved zone II or III. No patient had type 1 ROP requiring treatment. The short-term comorbidity incidence was high (76.1%) and included hyperbilirubinemia (n = 206, 76.7%), respiratory distress syndrome (n = 178, 66.4%), hypoglycemia (n = 32, 11.9%,), and transient tachypnea of newborn (n = 25, 9.3%). Moderate preterm infants were more likely to have lower birth weight (P < 0.001), any-stage ROP (P = 0.032), respiratory distress syndrome (P = 0.031), intraventricular hemorrhage (P = 0.038), and hyperbilirubinemia (P < 0.001) compared to the late preterm infants. CONCLUSIONS: Any-stage ROP incidence among MLP infants was low, with no type 1 ROP cases requiring treatment. Short-term comorbidity incidence was relatively high among the moderate preterm infants. Despite the low non-type 1 ROP incidence at our center, MLP infants require proper surveillance of systemic short-term comorbidities.

Retinopathy of prematurity.

Retinopathy of prematurity (ROP) is a devastating neurovascular disease of the retina in newborn infants that can lead to vision deficits or even blindness. In this concise review we discuss our current knowledge about diagnosis, etiology, pathogenesis, intervention, and outcomes of the disease. Major advancements have been made both in categorizing the disease in the new International Classification of Retinopathy of Prematurity, Third Edition classification and in treating severe ROP with anti-vascular endothelial growth factor (VEGF) agents. New development always creates new questions and opens up new areas of research. We will discuss in this review both the benefits and downsides of the new anti-VEGF treatment approaches in ROP, especially in light of our improved understanding of the underlying ROP pathophysiology. We also offer pointers to areas where more research is needed. WHAT THIS PAPER ADDS: Concise update on all aspects of retinopathy of prematurity (ROP), including advances in understanding and treatment. Benefits and risks of the new treatment method of anti-vascular endothelial growth factor injections in ROP are discussed. New research areas that deserve attention in the coming years are identified.

Prevalence and pattern of retinopathy of prematurity at two national referral hospitals in Uganda: a cross-sectional study.

BACKGROUND: Retinopathy of prematurity (ROP) is a leading cause of blindness in children and an ROP epidemic is predicted this decade in sub-Saharan Africa. With the increasing survival rate of preterm babies in Uganda, and no data on ROP prevalence, there is a need to assess the burden of ROP to inform preventive strategies and targeted screening. METHODS: We conducted a two-center cross-sectional study of preterm (< 37 weeks gestational age) infants from the neonatal units of Kawempe National Referral Hospital (KNRH) and Mulago Specialised Women and Neonatal Hospital (MSWNH) from August 2022 to October 2022. An ophthalmologist examined all participants using an indirect ophthalmoscope with a + 20D convex lens and captured digital images using a Volk iNview™ Fundus Camera. The collected data were entered into Epidata 4.2 and exported to Stata 14.0 for analysis. RESULTS: 331 preterm infants enrolled in this study. The oxygen received was unblended. The mean gestational age was 30.4 ± 2.7 weeks, and the mean birth weight was 1597 ± 509 g. 18/101 (17.8%) were found to have any ROP amongst the preterm infants recruited from MSWNH, 1/230 (0.4%) from KNRH [95% CI] had any stage of ROP (i.e. stage 5). Of these, 8 (42.1%) had stage 2 ROP. Infants with a birth weight below 1500 g were 10 times more likely to have ROP than those among infants with a birth weight more than 1500 g [AOR: 10.07 (2.71-37.44)]. Infants who were not fed exclusively on breast milk had higher odds of having ROP than those exclusively fed on breast milk [AOR: 7.82(1.92-31.82)]. CONCLUSION: 6% of preterm infants born in two tertiary hospitals in Uganda were found to have ROP. Lack of exclusive feeding on breast milk and birth weight of less than 1500 g were strong predictors of ROP. The higher prevalence of ROP in MSWNH calls for cautious use of oxygen among preterms. We recommend targeted ROP screening for those at risk.

Oxygen saturation levels and retinopathy of prematurity in extremely preterm infants - a case control study.

PURPOSE: To investigate the association of risk factors, including oxygen exposure, for developing retinopathy of prematurity (ROP) in preterm infants at increased risk of ROP. METHODS: A case-control study was conducted where each infant born at < 28 weeks gestation with ROP was matched with another without ROP over five years (July 2015 - June 2020). Clinical information about the infants was collected from electronic medical records, including method of oxygen delivery, oxygen saturation (SpO2), fraction of inspired oxygen (FiO2) and mean airway pressure (MAP) measurements. MATLAB was used for a time-averaged analysis. Stata/SE 16.0 was used for statistical analysis. RESULTS: 123 ROP/non-ROP pairs were included in this study. The time-averaged SpO2 analysis showed non-ROP group spent more time in hyperoxia than the ROP group (p < 0.001). The non-ROP group had lower respiratory severity scores and analysis when FiO2 > 21% showed that were was no difference in SpO2 between the two groups when the infants were receiving oxygen support. Conditional logistic regressions showed neonatal surgery significantly increased the risk of ROP (OR = 1.4347, p = 0.010), while the influence of birthweight (odds ratio of 0.9965, p = 0.001) and oxygen exposure (OR = 0.9983, p = 0.012) on ROP outcome was found to be negligible as their odds ratios indicated no influence. CONCLUSIONS: At times when infants were receiving respiratory support (FiO2 > 21%) the SpO2 data indicated no difference in SpO2 between the ROP and non-ROP groups. Analysis of clinical variables found that neonatal surgery increased the odds of developing ROP.

Erythrocyte transfusions are associated with retinopathy of prematurity in extremely low gestational age newborns.

AIM: Retinopathy of prematurity (ROP) is a major morbidity in preterm infants causing visual impairment including blindness. Prevention and timely treatment are critical. We investigated the potential role of red blood cell (RBC) transfusions as risk factor for ROP development. METHODS: Retrospective cohort study of data from 68 tertiary level neonatal intensive care units in Germany. Preterm infants born at 22 + 0 to 28 + 6 weeks of gestation between January 2009 and December 2021 were enrolled. RESULTS: We included n = 12 565 infants. Prevalence of any ROP was 49.2% with most infants being diagnosed with stage 1 (21.5%) and 2 disease (17.2%). ROP stage 3 was present in 10.2%, stage 4 in 0.3%, and ROP requiring treatment in 6.6%. Infants with ROP had significantly more frequently a history of RBC transfusions. Adjusting for confounders, RBC transfusions were associated with increased odds of ROP (OR 1.4, p < 0.001), ROP progression (OR 2.1, p < 0.01) and ROP requiring treatment (OR 3.6, p < 0.001). Restrictive transfusion approaches correlated with decreased (OR 0.7, p < 0.001), liberal regimes with increased odds (OR 1.2, p = 0.001). CONCLUSION: The present study confirmed an association of RBC transfusions and ROP. Our findings emphasise the need for anaemia prevention and critical re-evaluation of transfusion practices in preterm infants.

Increased risk of retinopathy of prematurity since increased O2 saturation targets: A multi-centre study.

BACKGROUND/AIMS: Retinopathy of prematurity (ROP) is a leading cause of visual impairment in premature neonates. The BOOST II, SUPPORT and COT trials recommended increasing O2 saturation targets for pre-term neonates to reduce mortality; however, this is a risk factor for ROP. We aimed to determine whether these targets increased prevalence of ROP among pre-term neonates and higher risk groups. METHODS: Retrospective cohort study conducted using data from the Australian and New Zealand Neonatal Network. 17 298 neonate cohort born 2012-2018 at <32 weeks' GA and/or <1500 g BW was analysed. Adjusted odds ratios (aORs) were calculated for post-2015 risk of: any ROP; ROP ≥ Stage 2; and treated ROP. Sub-analysis stratified at <28 GA, < 26 weeks' GA, <1500 g BW and <1000 g BW was performed. RESULTS: Risk of any ROP increased in the post-2015 group (aOR = 1.23, 95% confidence interval (CI) = 1.14-1.32), <28 weeks' GA (aOR = 1.31, 95% CI = 1.17-1.46), <26 weeks (aOR = 1.57, 95% CI = 1.28-1.91), <1500 g (aOR = 1.24, 95% CI = 1.14-1.34) and <1000 g (aOR = 1.34, 95% CI = 1.20-1.50). ROP ≥ Stage 2 increased at <28 weeks (aOR = 1.30, 95% CI = 1.16-1.46), <26 weeks (aOR = 1.57, 95% CI = 1.28-1.91), <1500 g (aOR = 1.18, 95% CI = 1.08-1.30), and <1000 g (aOR = 1.26, 95% CI = 1.13-1.42). CONCLUSION: O2 therapy guidelines since 2015 have resulted in decreased mortality but increased risk of ROP. Individualised NICU adjustments of ROP screening/follow-up methods are necessary to address the clinical burden.

Increased Risk of Retinopathy of Prematurity in Donors with Twin-to-Twin Transfusion Syndrome: A Cohort Study.

INTRODUCTION: The purpose of this study was to evaluate the within-pair difference in retinopathy of prematurity (ROP) between donors and recipients with twin-to-twin transfusion syndrome (TTTS) and to identify risk factors for ROP development. METHODS: This retrospective cohort study included 147 TTTS twin pairs managed between 2002 and 2022 and eligible for ROP screening. Primary outcomes were any stage ROP and severe ROP. Secondary outcomes were hemoglobin at birth, red blood cell transfusions, mechanical ventilation days, postnatal steroids, and neonatal morbidity. Donor status was defined as having polyhydramnios pre-laser. RESULTS: Rates of any stage ROP (23% vs. 14%) and severe ROP (8% vs. 3%) were significantly higher in donors compared to recipients. Donors received a higher number of blood transfusions (1 [±1.9] versus 0.7 [±1.5]). Five factors were univariately associated with any stage ROP: donor status (odds ratio [OR] 1.9; 95% CI 1.3-2.9), lower gestational age (GA) at birth (OR 1.7; 95% CI 1.4-2.1), small for GA (OR 2.1; 95% CI 1.3-3.5), mechanical ventilation days (OR 1.1; 95% CI 1.1-1.2), and blood transfusions in phase 1 (OR 2.3; 95% CI 1.2-4.3). Three factors were independently associated with any stage ROP: donor status (OR 1.8; 95% CI 1.1-2.9), lower GA at birth (OR 1.6; 95% CI 1.2-2.1), and mechanical ventilation days (OR 1.1, 95% CI 1.0-1.1). Donor status was univariately associated with severe ROP (OR 2.3, 95% CI 1.1-5.0). CONCLUSION: Any stage ROP and severe ROP are detected twice as frequently in donors compared to recipients. Increased awareness for ROP is needed in donors, especially those with lower GA at birth and longer duration of mechanical ventilation.

The role of hepatic and renal functions in the development of retinopathy of prematurity: Is proteinuria a new risk factor?

PURPOSE: To investigate the association of hepatic and renal parameters with the development of retinopathy of prematurity (ROP) in premature infants with a gestational age ≤ 32 weeks. METHODS: Medical records of 240 preterm infants were reviewed retrospectively, 85 of them were grouped as type 1, type 2 ROP, and control group. The 4th week hepatic and renal function test results of the groups, on the day of their first ROP examinations, were compared for the risk of development of ROP and the development of type 1 ROP. RESULTS: In this study, 12, 35, and 38 infants were enrolled in the type 1, type 2 ROP, and control group, respectively. The average gestational age and birth weight were higher; however, the duration of oxygen treatment was lower in the control group (p < 0.001). The blood glucose level was significantly higher in the type 1 ROP group than in the other groups (p = 0.023). The mean of total serum bilirubin of the type 1 ROP group was significantly lower than those of the type 2 ROP and control group (p = 0.032). Proteinuria was present in 85.7% of preterms with treatment-requiring ROP and proteinuria increased the risk of ROP by 3.9 times (OR with 95% CI 3.9 (1.19-12.75), p = 0.042). CONCLUSION: We found significantly higher blood glucose and lower total bilirubin level in the type 1 ROP group. Moreover, our findings suggest that proteinuria may not be only a comorbidity factor but also related to a higher frequency of ROP and type 1 ROP in preterm infants.

Oxygenation Factors Associated with Retinopathy of Prematurity in Infants of Extremely Low Birth Weight.

OBJECTIVE: To study characteristics of oxygenation during the first 2 postnatal months and correlation with the occurrence and severity of retinopathy of prematurity (ROP) among infants of extremely low birth weight. STUDY DESIGN: This retrospective study analyzed the incidence and severity of hyperoxemia and hypoxemia while on respiratory support with or without supplemental oxygen among infants of extremely low birth weight (birth weight <1000 g) admitted to the neonatal intensive care unit during 2016-2020. The findings were correlated with the occurrence and severity of ROP after adjusting for baseline covariates. RESULTS: After adjusting for differences in baseline demographic and clinical features, the group with severe ROP was exposed to greater fraction of inspired oxygen (FiO2) (P = .001) and experienced more frequent FiO2 titration adjustments (P = .001) compared with the group without ROP. Ambient air hyperoxemia occurred more frequently in the group without ROP (P = .003), and iatrogenic hyperoxemia occurred more frequently in the group with severe ROP (P = .046). There were no differences in the severity of ambient and iatrogenic hyperoxemia in the study population. The group with severe ROP demonstrated more hypoxemic episodes (P = .01) and longer time spent in the severe hypoxemic range (P = .005) compared with the group without ROP. CONCLUSIONS: Severe ROP is associated with greater FiO2 exposure, increased iatrogenic hyperoxemia, decreased ambient air hyperoxemia, and increased hypoxemia in infants of extremely low birth weight despite a greater frequency of FiO2 titration. This study illustrates the need for automated closed loop FiO2 delivery systems to further optimize oxygen saturation targeting in this high-risk population.

Lymphocytic microparticles suppress retinal angiogenesis via targeting Müller cells in the ischemic retinopathy mouse model.

Retinopathy of prematurity (ROP) is the primary cause of visual impairment and vision loss in premature infants, which results from the formation of aberrant retinal neovascularization (NV). An emerging body of evidence has shown that Müller cells are the predominant source of vascular endothelial growth factor (VEGF), which also serves as a chemoattractant for monocyte/macrophage lineage. The recruitment of macrophages is increased during retinal NV, and they exert a pro-angiogenic role in ROP. We have shown that lymphocytic microparticles (microvesicles; LMPs) derived from apoptotic human T lymphocytes possess strong angiogenesis-inhibiting properties. Here, we investigated the effect of LMPs on the chemotactic capacity of Müller cells in vitro using rat Müller cell rMC-1 and mouse macrophage RAW 264.7. In addition, the impact of LMPs was determined in vivo using a mouse model of oxygen-induced ischemic retinopathy (OIR). The results revealed that LMPs were internalized by rMC-1 and reduced their cell proliferation dose-dependently without inducing cell apoptosis. LMPs inhibited the chemotactic capacity of rMC-1 on RAW 264.7 via reducing the expression of VEGF. Moreover, LMPs attenuated pathological retinal NV and the infiltration of macrophages in vivo. LMPs downregulated ERK1/2 and HIF-1α both in vitro and in vivo. These findings expand our understanding of the effects of LMPs, providing evidence of LMPs as a promising therapeutic approach for the treatment of retinal NV diseases.

Incidence and risk factors for retinopathy of prematurity in premature, extremely low birth weight and extremely low gestational age infants.

BACKGROUND: The aim of the study was to determine the incidence and risk factors of retinopathy of prematurity (ROP) in premature, extremely low birth weight (BW, ELBW) and extremely low gestational age (GA, ELGA) infants. METHODS: The medical records of preterm infants who were screened for ROP between January 2012 and December 2020 were retrospectively reviewed. Only one eye of each infant with higher grade ROP was included in the study. BW; GA; medical characteristics; the presence, severity, and need for treatment of ROP were recorded. Infants were divided into groups according to BW (≤1000 g, 1001-1750 g, > 1750 g) and GA (≤25w, 26-28w, 29-31w, 32-34w, ≥35w) and data were analyzed. RESULTS: Data of 2186 infants were evaluated. The overall incidences of any stage ROP and ROP requiring treatment were 43.5 and 8.0%, respectively. These rates were 81.1 and 23.9% in ELBW (≤1000 g) infants and were 92.9 and 64.3% in ELGA (≤25w) infants, respectively. The rates of ROP, the median duration of oxygen therapy and systemic diseases increased significantly as BW and GA decreased. The median duration of oxygen therapy and the rates of sepsis, pulmonary dysplasia (BPD), and intraventricular hemorrhage (IVH) were statistically higher in infants with ROP compared to those without ROP (p < 0.001). Multivariate regression analysis demonstrated that low BW and GA; prolonged duration of oxygen therapy; presence of PDA and necrotizing enterocolitis (NEC) were important risk factors for ROP. CONCLUSIONS: ELBW and ELGA infants develop higher rates of ROP and severe ROP. Prolonged duration of oxygen therapy, the presence of concomitant neonatal sepsis, BPD, IVH, PDA, and NEC further increases the risk of ROP.

The Role of Thrombocyte Parameters in Retinopathy of Prematurity Development.

Purpose: To investigate the role of thrombocyte parameters in retinopathy of prematurity (ROP) development. Materials and Methods: This retrospective study included 120 preterm infants in total. Group 1 was formed by infants who developed type-1 ROP and received treatment. Group 2 was formed by infants who developed ROP and were not treated for ROP. Infants who did not develop ROP and whose retinal vascularization was completed in their follow-up formed Group 3. Gestational age, birth weight, and genders of groups were recorded. Platelet (PLT) count, mean platelet volume (MPV), and platelet distribution width (PDW) values were obtained from complete blood count. Platelet mass index (PMI) was calculated by multiplying the PLT count by MPV value. Thrombocytopenia was defined as PLT count <150 × 1000/µL. All parameters were compared between the groups. Results: There were 40 preterm infants in each group. The mean PLT count was 272.43 ± 122.67 in Group 1, 333.32 ± 133.06 in Group 2, and 310.03 ± 119.41 in Group 3. The difference in PLT count between the groups was not significant (p=0.094). Thrombocytopenia was observed in 25% of Group 1, 10% of Group 2, and 10% of Group 3 (p=0.095). No statistically significant difference was found in terms of MPV, PDW, and PMI values between the groups (p=0.102, p=0.097, and p=0.298, respectively). Conclusions: Although PLT count was lower and thrombocytopenia rate was higher in the type-1 ROP group, the differences were not found to be significant. Further prospective studies are required to evaluate the role of thrombocytes in ROP pathogenesis.

New Aspects on the Treatment of Retinopathy of Prematurity: Currently Available Therapies and Emerging Novel Therapeutics.

Retinopathy of prematurity (ROP) is a rare proliferative ocular disorder in preterm infants. Because of the advancements in neonatal care, the incidence of ROP has increased gradually. Now, ROP is one of the leading causes of blindness in children. Preterm infants with immature retinal development are exposed to supplemental oxygen inside an incubator until their cardiopulmonary system is adequately developed. Once they are returned to room air, the relatively low oxygen level stimulates various angiogenesis factors initiating retinal neovascularization. If patients with ROP are not offered adequate and timely treatment, they can experience vision loss that may ultimately lead to permanent blindness. Although laser therapy and anti-vascular endothelial growth factor agents are widely used to treat ROP, they have limitations. Thus, it is important to identify novel therapeutics with minimal adverse effects for the treatment of ROP. To date, various pharmacologic and non-pharmacologic therapies have been assessed as treatments for ROP. In this review, the major molecular factors involved in the pathogenesis of ROP, currently offered therapies, therapies under investigation, and emerging novel therapeutics of ROP are discussed.

Lung and Eye Disease Develop Concurrently in Supplemental Oxygen-Exposed Neonatal Mice.

Bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) are two debilitating disorders that develop in preterm infants exposed to supplemental oxygen to prevent respiratory failure. Both can lead to lifelong disabilities, such as chronic obstructive pulmonary disease and vision loss. Due to the lack of a standard experimental model of coincident disease, the underlying associations between BPD and ROP are not well characterized. To address this gap, we used the robust mouse model of oxygen-induced retinopathy exposing C57BL/6 mice to 75% oxygen from postnatal day 7 to 12. The cardinal features of ROP were replicated by this strategy, and the lungs of the same mice were simultaneously examined for evidence of BPD-like lung injury, investigating both the short- and long-term effects of early-life supplemental oxygen exposure. At postnatal days 12 and 18, mild lung disease was evident by histopathologic analysis together with the expected vasculopathy in the inner retina. At later time points, the lung lesion had progressed to severe airspace enlargement and alveolar simplification, with concurrent thinning in the outer layer of the retina. In addition, critical angiogenic oxidative stress and inflammatory factors reported to be dysregulated in ROP were similarly impaired in the lungs. These data shed new light on the interconnectedness of these two neonatal disorders, holding potential for the discovery of novel targets to treat BPD and ROP.

Effect of a Novel Oxygen Saturation Targeting Strategy on Mortality, Retinopathy of Prematurity, and Bronchopulmonary Dysplasia in Neonates Born Extremely Preterm.

OBJECTIVE: To study the impact of an oxygen management strategy incorporating oxygen saturation (SpO2) targeting and fraction of inspired oxygen monitoring on the incidence of retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), and mortality. STUDY DESIGN: This retrospective cohort study analyzed the incidence of any ROP, severe ROP, ROP requiring treatment (surgery and/or bevacizumab), BPD, and mortality among 23-28 weeks of gestational age infants admitted to the neonatal intensive care unit in 3 epochs: Epoch 1 (2007-2010) before implementation of SpO2 histograms; Epoch 2 (2012-2014), with development of a software tool capable of generating automatic bedside SpO2 histograms; and Epoch 3 (2016-2019), with further software enhancements, incorporating simultaneous SpO2 and fraction of inspired oxygen measurements. RESULTS: During Epochs 1, 2, and 3, there were 601, 381, and 550 eligible infants, respectively, for a total of 1532 eligible infants. Mortality, any ROP, severe ROP, ROP needing treatment, and BPD all showed significant downward trends across the 3 epochs. The aOR of mortality was significantly lower in Epoch 3 compared with Epoch 1 (aOR 0.48). The aORs of any ROP and of BPD were significantly lower in Epochs 2 and 3 compared with Epoch 1 (respectively, ROP aORs 0.53 and 0.38; BPD aOR 0.43 and 0.43). The aOR of ROP needing treatment was significantly lower in Epoch 3 compared with Epoch 1 (aOR 0.43). CONCLUSIONS: We have demonstrated improvement in rates of mortality, any ROP, ROP requiring treatment, and BPD after implementation of a novel oxygen management strategy.

CM082, a novel VEGF receptor tyrosine kinase inhibitor, can inhibit angiogenesis in vitro and in vivo.

The goal of this study was to evaluate the effects of CM082, a novel vascular endothelial growth factor (VEGF) receptor-2 tyrosine kinase inhibitor, on human umbilical vein endothelial cells (HUVECs), and oxygen-induced retinopathy (OIR) mice. HUVECs were stimulated with rHuVEGF165 and then treated with CM082 to assess the antiangiogenic effects of CM082; subsequently, proliferation, wound-healing migration, Transwell invasion, tube formation assays, and Western blotting were performed in vitro. Retinal neovascularization tufts, avascular area, and TUNEL assays were estimated for OIR mice after intraperitoneal injection with CM082. CM082 significantly inhibited proliferation, migration, invasion, and tube formation induced by stimulation of HUVECs with rHuVEGF165; this inhibitory effect was mediated by blocking VEGFR2 activation. CM082 significantly inhibited retinal neovascularization and avascular area and did not increase apoptosis in the retina of OIR mice. The findings demonstrated that CM082 exhibits highly antiangiogenic effects in HUVECs and OIR mice. Thus, it may serve as an alternative treatment for neovascular eye disease in the future.