Retinopathy of prematurity in multiple-gestation pregnancies

Perinatal and neonatal risk factors for retinopathy of prematurity in very low birthweight, very preterm twins: a population-based study

OBJECTIVE

To determine the effect of perinatal and neonatal risk factors on retinopathy of prematurity (ROP) and to examine the association of fertility treatments on the risk for ROP in very low birth weight (VLBW) preterm twins.

METHODS

The population-based observational study consisted of VLBW twins born at 24-29 weeks gestational age (GA). Data from the Israel national database (1995-2020) were applied. Univariate and multivariable logistic regression using the General Estimating Equation were used for assessment of risk factors.

RESULTS

The study population comprised 4092 infants of whom 2374 (58%) were conceived following fertility treatments. ROP was diagnosed in 851 (20.8%) infants. The odds for ROP approximately doubled with each week decrease in GA: at 24 weeks, Odds Ratio (OR) 58.00 (95% confidence interval (CI) 31.83-105.68); 25 weeks, OR 25.88 (95% CI 16.76-39.96); 26 weeks, OR 12.69 (95% CI 8.84-18.22) compared to 29 weeks GA. Each decrease in one birthweight z-score was associated with 1.82-fold increased risk for ROP (OR, 1.82, 95% CI 1.59-2.08). Infertility treatments were not associated with ROP. Neonatal morbidities significantly associated with ROP were surgical necrotizing enterocolitis (NEC) (OR, 2.04, 95% CI 1.31-3.19); surgically treated patent ductus arteriosus (PDA) (OR, 1.63, 95% CI 1.12-2.37); sepsis (OR, 1.43, 95% CI 1.20-1.71) and bronchopulmonary dysplasia (OR, 1.52, 95% CI 1.22-1.90).

CONCLUSION

Among preterm VLBW twins, poor intrauterine growth and surgical interventions for NEC and PDA were associated with high odds for ROP. This study does not support an association of fertility treatments with increased risk for ROP.

Retrospective Comparative Analysis of Neonatal Mortality and Morbidity in Preterm Singleton and Multiple Births -Single Center Experience

Objective. To compare mortality and major neonatal morbidities between singleton preterm infants and preterm infants of multiple gestations born <33 weeks' gestation. Method. Case-control study of preterm multiples and singletons <33 weeks' born at King Abdul-Aziz Medical City Riyadh (KAMC-R) between January 2017 and December 2020. Out-born infants and infants with lethal congenital abnormalities were excluded from the study. Mortality and major neonatal morbidities including bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), sepsis and surgical necrotizing enterocolitis (NEC) were compared between preterm singletons and multiples. Results. A total of 803 preterm infants were included: 567 (70.6%) were singletons, 158 (19.6%) were twins and 36 (4.5%) infants were higher multiples. Adjusted mortality before hospital discharge was significantly higher among preterm infants of multiple gestations compared to preterm singletons (12.3% vs 7.9%; P = .003; AOR, 2.2; 95% CI, 1.3-3.7). Retinopathy of prematurity (ROP) needing treatment was significantly higher among preterm infants of multiple pregnancies compared to preterm singletons (11% vs 6.5%, P = .033, AOR 1.1, 95% CI, 1.04-2.99). In addition, the incidence of bronchopulmonary dysplasia (BPD) at 36 weeks post menstrual age (PMA) (29.7% vs 20.5%; P = .003; AOR, 1.7; 95% CI, 1.2-2.5) and culture positive sepsis (24.2% vs 17.5%; P = .044; AOR, 1.5; 95% CI, 1.01-2.2) were significantly higher among preterm infants of multiple pregnancy. There were no differences in mortality and adverse neonatal outcomes between twins and higher multiples. Conclusion. Preterm infants of multiple gestations suffered higher mortality and neonatal morbidities compared to preterm singleton infants despite a higher utilization of maternal antenatal steroids and better antenatal care.

Comparative analysis of risk factors for retinopathy of prematurity in single and multiple birth neonates

AIM

To conduct a comparative analysis of risk factors for retinopathy of prematurity (ROP) in single- and multiple-born neonates.

METHODS

In a retrospective evaluation of 521 premature neonates, encompassing singletons, twins, and triplets born at or before 34 weeks of gestational age with a birthweight of less than 2000 g and who completed the ROP screening program, between 2020 and 2023, in outpatient referral ROP screening clinic affiliated by Shiraz University of Medical Sciences, were included. Neonates with the eligibility criteria were enrolled in the screening program from 28 days old age and followed up to discharge or treatment based on national ROP screening guideline. Data on ROP severity, outcome, treatment modality, and risk factors, including gestational age (GA), birth weight (BW), sex, duration of neonatal intensive care unit (NICU) admission, oxygen supplementation, mechanical ventilation, blood transfusion, method of delivery, and maternal and neonatal comorbidities, were extracted and compared between premature neonates from singleton and multiple births.

RESULTS

The analysis of the ROP severity distribution revealed 238 neonates (45.7%) with low-risk (type 2 prethreshold ROP or less severe) ROP and 16 (3.1%) with high-risk (type I prethreshold ROP or more severe) ROP who underwent treatment. According to the comparative analysis of risk factors in neonates with ROP requiring treatment, multiple birth neonates exhibited significantly greater GA (27.50 ± 3.27 vs. 30.00 ± 2.00 vs. 31.14 ± 0.38 weeks, p = 0.032 for singletons, twins and triplets, respectively); greater BW (861.67 ± 274.62 vs. 1233.33 ± 347.75 vs. 1537.14 ± 208.86 g, p = 0.002); and shorter duration of NICU admission (60.17 ± 21.36 vs. 34.00 ± 12.17 vs. 12.00 ± 6.32 days, p = 0.001) and oxygen supplementation (47.33 ± 16.57 vs. 36.00 ± 8.49 vs. 4.60 ± 2.41 days, p = 0.001). There was no significant difference between single-born neonates and multiple-born neonates regarding the prevalence of other risk factors. Multiple-born neonates with no ROP and low risk ROP showed significantly lower GA and BW compared to singletons (p < 0.001).

CONCLUSION

Multiple gestation neonates may develop high-risk ROP requiring treatment at a greater gestational age and birth weight and at a lower duration of oxygen supplementation and NICU admission compared to the single birth neonates. This pattern prompts a reevaluation of screening criteria, suggesting a potential need to consider multiple birth neonates with lower traditional risk factors in screening programs. This pattern should be further evaluated in larger populations of multiple born premature neonates.

Incidence and Risk Factors for Retinopathy of Prematurity in a Tertiary Hospital in China

Purpose

To investigate the incidence and risk factors for the retinopathy of prematurity (ROP) in the neonatal intensive care unit (NICU) of Obstetrics and Gynecology Hospital of Affiliated to Nanjing Medical University, China.

Methods

This retrospective case-control study included 611 preterm infants with birth weight (BW)<1500 grams admitted to the Department of Neonatology, Obstetrics and Gynecology Hospital of Affiliated to Nanjing Medical University between January 2019 and December 2022. The incidence and risk factors for any stage and severe ROP were analyzed.

Results

Within 611 infants, 245(40.1%) developed ROP; 160(26.2%) infants were stage 1, 54(8.8%) were stage 2, and 31(5.1%) were stage 3, no stage 4 and 5. Among them, 22(3.6%) infants needed treatment. Multivariate analysis showed a higher gestational age (GA) was protective, whereas twin birth and moderate-to-severe BPD increased the hazard of any stage ROP; higher BW and male gender were significant risk factors for severe ROP.

Conclusion

Compared to other tertiary hospitals, the incidence of any stage ROP in our NICU was higher, but the rate of ROP needed treatment was lower. A higher GA was protective, whereas twin birth and moderate-to-severe BPD increased the hazard of any stage ROP; higher BW was protective, whereas male gender were risk factors for the development of severe ROP.

Treatment for Retinopathy of Prematurity in Twins: The Small Twin without High Birth Weight Discordant Is Not at Increased Risk

Purpose: As common retinopathy is observed in low-birth infants, the characteristics of ROP in twins are worth exploring. The present study tried to demonstrate the risk factors of treatment for retinopathy of prematurity (ROP) in twins both diagnosed with ROP. Methods: A retrospective, institution-based cohort study of 62 premature ROP twin pairs with a mean gestational age (GA) younger than 35 weeks and a birth weight (BW) lower than 2500 g. Only infants with a follow-up period longer than 6 months and complete treatment records were included. The demographic data, treatment requirements and further rescue treatments were all collected and analyzed for all infants according to whether they accepted treatments. Moreover, all twin infants were divided into small and large twin groups according to birth weight, and they were also categorized as three groups according to the treatment requirement including both twins receiving treatment (BT group), one of the twins receiving treatment (ST group) and none of the twins receiving treatment (NT group). Comparisons of demographic data, treatment requirements and further rescue treatments were all conducted according to the different grouping methods. Results: The mean GA of the enrolled infants was (29.29 ± 2.45) weeks with a mean BW of (1335.77 ± 390.36) grams. Among them, 110 infants were mechanically ventilated. Fifty-one of the infants did not receive any treatment and 73 infants received laser or intravitreal injection of anti-VEGF agents. In total, 64 infants only underwent intravitreal injection of anti-VEGF agents or laser treatment, while the other nine infants received scleral buckling or vitrectomy as a necessary treatment when the retinal detachment was observed. No significantly different mechanical ventilation or treatment requirements could be observed between the small twin group and the large twin group (p = 0.73, 0.94). The twins in the BT groups showed the lowest BW, while the NT group infants had the highest BW. The GA for the BT, ST and NT groups were (27.86 ± 1.87) weeks, (29.60 ± 1.52) weeks and (31.33 ± 2.39) weeks, respectively, and showed significant differences as well (p < 0.001). Conclusion: Being a small twin in twin-paired ROP without a high BW discordant will not increase the risk for treatment requirement or additional surgery necessity with a much more severe stage of ROP.

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.

Perinatal risk factors for development of retinopathy of prematurity in a tertiary neonatal intensive care unit

OBJECTIVE

Retinopathy of prematurity (ROP) is a vasoproliferative disorder that is one of the main preventable causes of blindness among preterm neonates. This study aimed to determine the incidence of ROP and investigate the relationship between perinatal risk factors and ROP development.

METHODS

This retrospective, non-interventional, non-comparative, hospital-based study was conducted at a tertiary-level neonatal intensive care unit. A total of 163 consecutive patients who met the inclusion criteria were recruited in this study.

RESULTS

ROP prevalence was 0.01. During the study period, 44 patients developed ROP (27%), and 119 (73%) did not. Stage I ROP was detected in 8 patients (4.9%); stage II ROP without plus-disease in 26 patients (16%); stage II disease with comorbidities in 1 patient (0.6%); and stage III disease in 9 patients (5.5%). None of the patients showed stage IV and V disease. The mean gestational age was 27.7 ± 2.08 weeks in babies who had ROP and 29.59 ± 1.80 weeks in the other group. Neonates with ROP required more frequent blood transfusion (average, 4.89 ± 3.164 transfusions) compared to their counterparts who received an average of 1.19 ± 1.733 transfusions. Intracranial haemorrhage was identified in 55 (33.7%) patients, of whom 14.1% had ROP. Moreover, neonatal seizures occurred in 23 (14.11%) babies and were more common among babies who had ROP (n = 14).

CONCLUSION

This study identified key factors associated with ROP, such as intracranial haemorrhage with or without neonatal seizures and a high frequency of blood transfusions.

Artificial Reproductive Technology - A Risk Factor for Retinopathy of Prematurity

BACKGROUND:

Retinopathy of Prematurity (ROP) is a potentially blinding vasoproliferative disease in premature babies. The presentation and course of ROP are determined by a complex interaction of a series of risk factors, including artificial reproductive technology (ART).

AIM:

To analyse and combine the information relating ART as an independent risk factor for retinopathy of prematurity.

METHODS AND MATERIAL:

The article is systematic review and meta-analysis using RevMan 5. Pubmed, Scopus and Medline were searched for articles from 1990 to 2018.

RESULTS:

Studies suggest that ROP is observed more frequently in ART children. They are more likely to be premature and of low birth weight than those conceived naturally. Results vary from just a tendency to a five-fold increase in risk to develop ROP in ART babies. At the same time, they might develop ROP later, and more mature newborns might be affected.

CONCLUSION:

The data relating ART as a risk factor for ROP is inconclusive, but most studies show at least a tendency. The ART newborns need to be considered as a risk group for ROP and observed with greater suspicion. Even more mature ART newborns might need to be screened in order not to miss any significant pathology.

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

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Long-term refractive status of preterm infants from singleton and multiple pregnancies. J Matern Fetal Neonatal Med 2016;30:2276-2280. [PMID: 27718778 DOI: 10.1080/14767058.2016.1245719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

OBJECTIVE

To study the effect of plurality on refractive status in former preterm infants at age 8-12 years.

METHODS

Refraction was compared in singletons and multiples, in very low birth weight infants (VLBW, <1500 g) at age 6 months and 8-12 years. Preterm infants were compared with a group of term infants.

RESULTS

Thirty-seven of 104 (36%) VLBW infants were multiples. Comparison of refraction between singletons and multiples revealed no difference at age 6 months, while at age 8-12 years, multiples had significantly more refractive errors (singletons 28% versus multiples 54% p = 0.01), particularly myopia. In preterms, refractive status at age 6 months and multiple birth were significant predictors of refraction at 8-12 years, while birth weight (BW) and retinopathy of prematurity (ROP) were not predictive. Refractive errors were significantly more common in preterms (37%) than in term-born children (14%) (p = 0.0002). Overall, refraction moved from predominantly hyperopic at 6 months to normal or myopic at age 8-12 years in preterm.

CONCLUSIONS

Multiple gestation in preterms is associated with increased risk for refractive errors, particularly myopia in childhood. Refraction in preterms during childhood progresses from hyperopia to myopia. Former preterms have more refractive errors than children born at term-born children.

Is artificial reproductive technology a risk factor for retinopathy of prematurity independent of the generation of multiple births?

PURPOSE

There is some debate regarding whether artificial reproductive technology (ART) constitutes an independent risk factor for retinopathy of prematurity (ROP). We wanted to assess the prevalence of ART in multiple birth infants seen for ROP screening and whether or not ROP was identified or treated, in order to evaluate whether ART contributes a risk factor for ROP independent of the generation of multiple births.

METHODS

A retrospective audit was performed of all multiple birth babies admitted to a tertiary neonatal unit who met the UK ROP screening criteria (<32 weeks gestational age [GA] and/or <1,501 g birthweight [BW]).

RESULTS

A total of 205 babies met our criteria, of whom 87.3% were twins. A total of 39.5% were born following ART. A total of 30.5% of the non-ART group developed ROP vs 34% of the ART group (p = 0.837). Stage 3 ROP developed in 5.1% of non-ART babies and 6% of ART babies. A total of 8.5% of non-ART babies and 10% of ART babies required treatment for ROP. Logistic regression demonstrated that ART was not independently associated with development of ROP.

CONCLUSIONS

Artificial reproductive technology multiple birth babies make up a considerable proportion of the ROP screening burden and their number is likely to increase as ART is increasingly available and utilized. We found no significant difference between the numbers of babies developing ROP in the ART vs non-ART groups, but the numbers are small. The estimated odds of developing ROP are slightly higher in the ART babies, so our data do not rule out a possible association.

Retinopathy of Prematurity in Neonates and its Risk Factors: A Seven Year Study in Northern Iran

Purpose:

An important cause of avoidable childhood blindness is retinopathy of prematurity (ROP) in countries with high human development index and also in some emerging economies countries. To date, no research have been conducted on analyzing data of ROP prevalence in Babol, and this is the first research performed on ROP in this area.

Methods:

All VLBW babies who referred to Babol ophthalmology center over the seven years, from February 2007 to December 2013 were enrolled in this descriptive cross-sectional research. A team of researchers recorded patients’ information completely in check lists. A single experienced ophthalmologist performed ophthalmologic examination of patients.

Result:

The incidence of ROP of any stage in Babol was determined to be 306 (45%) of all babies enrolled in this study. In present study, key risk factors of ROP were low gestational age, oxygen therapy more than five days and low birth weight.

Conclusion:

The findings of current study demonstrate that the main risk factors of developing ROP in newborns are multiple gestation, low birth weight, oxygen therapy for more than five day. Therefore, the progression of ROP to blindness will be prevented by a high index of suspicion, suitable screening, prompt diagnosis, and early treatment.

Incidence and risk factors for retinopathy of prematurity in multiple gestations: a Chinese population study

To determine the incidence and risk factors of retinopathy of prematurity (ROP) among new-born Chinese infants of multiple gestations.A retrospective review of medical records was performed for all neonates of multiple gestations screened for ROP between January 2007 and December 2012 in 2 neonatal intensive care units in Hong Kong. Screening was offered to very low birth weight (VLBW; ≤1500 g) and/or preterm (gestation ≤32 weeks) neonates using the Royal College of Ophthalmologists ROP guideline and the International Classification of ROP by 3 pediatric ophthalmologists. Maternal and neonatal covariates were analyzed using univariate and multivariate regression analyses for both ROP and Type 1 ROP.A total of 153 Chinese infants of multiple gestations were included in the study. The mean gestational age (GA) was 30.8 ± 2.4 weeks and the mean birth weight (BW) was 1284.8 ± 267.4 g. The incidence of ROP and Type 1 ROP was 11.8% and 3.9%, respectively. On univariate analysis, younger GA, lighter birth weight, postnatal hypotension, inotropes use, bronchopulmonary disease, and intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP (all P ≤ 0.04). On multivariate analysis, younger GA, surfactant use, invasive mechanical ventilation, higher mean oxygen concentration, thrombocytopenia, intraventricular hemorrhage, total parental nutrition, and hypoglycemia were significant risk factors for ROP. For Type 1 ROP, there were no significant dependent risk factors.In preterm Chinese infants born from multiple gestations, prematurity, lighter weight, postnatal hypotension, inotropes use, bronchopulmonary dysplasia, and an intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP.

Multiple pregnancies and its relationship with the development of retinopathy of prematurity (ROP)

Background

The influence of multiple gestation on the occurrence of retinopathy of prematurity (ROP) is still not completely understood.

Objectives

To verify the incidence of any stage of ROP and threshold ROP in singletons and in multiple gestation among preterm infants.

Methods

This was an institutional, prospective, and descriptive cohort study, which included preterm newborns with birth weight (BW) of 1500 g or less and/or gestational age (GA) of 32 weeks or less, as admitted to the neonatal units at Laranjeiras and Amparo Hospitals in Rio de Janeiro, Brazil, between January 2001 and July 2005, and whom remained hospitalized for at least 28 days. There were no exclusion criteria. Patients were divided into two groups: Group 1 included multiples; and Group 2 consisted of singletons.

Results

A total of 159 infants that remained in neonatal unit care for at least 28 days were included in this study. Group 1 comprised 56 (35%) multiples; and Group 2 comprised 103 (65%) singletons. Mean BW was 1072 g ± 272 and 1089 g ± 282 in Groups 1 and 2, respectively (analysis of variance [ANOVA] P > 0.05). Mean GA among multiple gestation (Group 1) was 29 weeks ± 2.1; and 29 weeks ± 2.4 among singletons (Group 2) (ANOVA P > 0.05). Days in oxygen therapy ranged from 0 to 188 days. Median among Group 1 was 15 days, while median in Group 2 was 10 days (Kruskal–Wallis P > 0.05). Any stage ROP was detected in 66 (41.5%) of the whole cohort comprising 159 babies. Among the 56 multiples, 30 (53.6%) achieved any stage ROP, and among 103 singletons, 36 (35%) achieved any stage ROP (Chi-square test P < 0.05). Threshold ROP occurred in 12 (7.5%) of the 159 patients included. Three (5.3%) patients from Group 1 and nine (8.7%) patients in Group 2 reached threshold ROP needing laser treatment (Fisher’s exact test P > 0.05).

Conclusion

This study showed higher frequency of any stage of ROP in twins and triplets but not regarding threshold disease. Because of the relatively small number of patients in this sample, other studies are necessary to determine if gemelarity plays a role in the occurrence of ROP.

Association between assisted reproductive technology and advanced retinopathy of prematurity

Purpose

To investigate the associations between assisted reproductive technology (ART) and severe retinopathy of prematurity (ROP) requiring treatment.

Methods

Retrospective analyses of inborn preterm infants screened for severe ROP at the Weill Cornell Medical Center Neonatal Intensive Care Unit at the New York-Presbyterian Hospital by single factor logistic regression and multifactor models.

Results

Of 399 ethnically diverse infants, 253 were conceived naturally and 146 by ART. Eight (3.16%) patients conceived naturally, and 11 (7.53%) with ART required laser treatment. In multifactor analyses, significant risks for severe ROP requiring treatment included both gestational age (odds ratio [OR] 0.34; 95% confidence interval [CI] 0.23–0.52; P < 0.001) and ART ([OR] 4.70; [CI], 1.52–4.57; P = 0.007).

Conclusions

ART is associated with severe ROP requiring treatment in this cohort. This is the first report that demonstrates a statistically significant association between ART and severe ROP requiring treatment in infants in the US.

Profile of asymmetrical retinopathy of prematurity in twins

Background:

In twin births, both babies have the same gestational age and pre-natal conditions. However, twins may develop a varied retinopathy of prematurity (ROP) course depending on birth weight and other systemic factors.

Objective:

To study the profile of asymmetric ROP in twins

Design:

Retrospective study

Setting:

Tertiary ROP referral eye hospital.

Materials and Methods:

The profile of 56 pairs of twins with ROP were studied and analyzed for differences in zone or need for treatment, while studying possible causes for the varied outcome.

Results:

In 45 pairs of twins (80%) the disease progressed identically in both eyes, while in 11 pairs (20%) the ROP showed differences in zone or need for treatment. Four of these pairs were discordant. In 3 of these 4 pairs, the heavier birth weight twin had a more severe ROP course.

Conclusions:

Twins can present with asymmetric ROP course, and it is therefore essential to examine both twins as per screening protocols.

Retinopathy of prematurity in assisted versus natural conception and singleton versus multiple births

OBJECTIVES

To determine whether the incidence and severity of retinopathy of prematurity (ROP) differs between infants conceived naturally and those born after assisted conception, and to analyze the impact of singleton versus multiple gestation on ROP.

DESIGN

Comparative case series.

PARTICIPANTS

The study group consisted of 363 infants with a birth weight (BW) of < or =1500 g who were hospitalized in the neonatal unit of a single tertiary-care center between 1998 and 2000.

METHODS

Data on gestational age (GA), BW, type of pregnancy (singleton/multiple), and type of conception (natural/assisted) were recorded, in addition to the ophthalmological results. Ophthalmological examinations were performed routinely at 4 weeks and repeated later, depending on the severity of the findings.

MAIN OUTCOME MEASURES

Presence and stage of ROP were compared between infants conceived naturally and those conceived by assisted technology, and between singleton and multiple-birth infants.

RESULTS

Mean GA at birth was 29.4 weeks (standard deviation, 2.5; range, 23-36). Two hundred four neonates (56.2%) were conceived naturally and 159 were conceived by assisted conception, either in vitro fertilization (IVF) alone (n = 119 [32.85%]) or IVF combined with drug treatment (n = 40 [11%]). Sixty-four infants in the natural conception group were the product of multiple pregnancies, as were 103 infants in the assisted conception group. Retinopathy of prematurity was noted in 159 of 363 infants (43.8%): 89 conceived naturally (71% singletons, 28% twins, and 17% triplets) and 70 born by assisted conception (70% singletons, 47% twins, and 33% triplets). There was no significant difference in either occurrence or severity of ROP between the natural conception and assisted conception groups. Singletons had a significantly higher rate of advanced ROP (stages II-III) (30.2%) than twins (23.1%), triplets, and quadruplets (10.6%) (P = 0.024). On multiple regression analysis, low GA and BW were the variables most significantly associated with ROP.

CONCLUSIONS

In our sample, assisted conception per se did not appear to be a risk factor for ROP. Singleton babies with a birth weight of < or =1500 g were more prone to develop ROP stages II and III than twins or triplets. Gestational age and BW were the most significant factors associated with ROP.

Eye-hand co-ordination skills in very preterm infants <29 weeks gestation at 3 years: Effects of preterm birth and retinopathy of prematurity

INTRODUCTION

Preterm infants are known to have low gross motor and fine motor skills. We questioned whether poor eye-hand coordination skills are associated with moderate to severe stages of Retinopathy of Prematurity (ROP).

AIMS

The aim of this study was to examine development, with specific reference to eye-hand coordination skills, among preterm infants <29 weeks gestation with different stages of ROP at 3 years of age.

METHODS AND MATERIALS

Fifteen preterm infants (<29 weeks gestation) who developed Stage 3 ROP were matched for gestation, birthweight and gender with infants who developed Stage 2 and Stage 1/no ROP. Developmental (Griffiths Mental Development Scales and Peabody Developmental Motor Scales) and ophthalmic assessments in the 3 matched groups of 15 were performed at 3 years of age.

RESULTS

1) Whilst the eye-hand coordination scores and Peabody fine motor scores were lower in the Stage 3 ROP group, they were not significantly lower than the other ROP groups. 2) Locomotor, Peabody gross motor skills and hearing and speech were significantly lower in the infants with Stage 3 ROP. The other developmental domains were not significantly different to the severe ROP group. 3) All 3 groups (of preterm infants) had lower eye-hand coordination and Peabody fine motor scores compared to test norms. 4) There were 8 of 15 infants with Stage 3 ROP who developed moderate visual problems by 3 years of age.

CONCLUSION

In preterm infants, low eye-hand coordination/fine motor scores are likely to be due to their extreme prematurity.

Assisted conception and retinopathy of prematurity: 8-year follow-up study

AIMS

To assess the effect of assisted conception (AC) on retinopathy of prematurity (ROP) and ROP screening. Follow-up to the study by McKibbin et al.

METHODS

Retrospective study utilising computerised databases of ROP screening, live births, AC and multiple births between 1st April 2000 and 31st August 2003 at St James's Hospital (SJUH) Leeds. chi(2) tests of significance were used.

RESULTS

ROP screening was undertaken in 11/265 (4.2%) of AC births versus 1.6% of all SJUH births. This is significantly less than the 20.3% of AC babies screened in McKibbin et al study (P=<0.01). There was no ROP detected in the 11 AC babies. Of all AC births, 36.9% were one of twins and 1.5% from triplet births compared to 46.0% one of twins and 18.6% one of triplets in McKibbin's study.

CONCLUSIONS

The percentage of AC babies requiring ROP screening has fallen since McKibbin et al study which was performed between August 1991 and December 1994. This appears to be at least partially due to the reduced multiple birth rates. This reduction in the multiple birth rates follows evidence that reducing the number of embryos transferred does not reduce the number of couples taking home a baby and Human Fertility and Embryology Association guidelines recommending 'no more than two embryos should be transferred in an IVF cycle'. Changes in clinical practice at SJUH have significantly reduced the likelihood of AC babies requiring ROP screening and developing ROP.

Ophthalmologic follow-up of premature twins and triplets

PURPOSE

To assess the influence of multiple gestation on the visual apparatus and on the general state of health of premature infants and to investigate the condition of the twin or triplet with the lowest birth weight compared to multiple gestation siblings.

METHODS

Seventy-seven premature twins or triplets (8 to 54 months of age) were monitored at the Verona University Ophthalmology Department from November 1995 to November 1999. In another 12 subjects (younger than 8 months), only the neonatal disease records were examined; these subjects were excluded from the ophthalmologic follow-up because they were too young to be tested reliably. The study sample was compared with 120 premature singletons monitored from January 1996 to March 1998. Visual acuity, ocular motility, strabismus, refraction defects, dioptric media, and fundus oculi were assessed.

RESULTS

The incidence of retinopathy of prematurity, refraction defects, or strabismus was not significantly different between premature twins or triplets and premature singletons. The twin or triplet with the lowest birth weight was more frequently affected by eye morbidity and the diseases typical of prematurity. This difference, however, was not statistically significant.

CONCLUSIONS

Premature infants are at a disadvantage compared to those born at term, irrespective of multiple birth status; multiple gestation adds no risk beyond that due to prematurity.

Retinopathy of prematurity in VLBW and extreme LBW babies

OBJECTIVE

This is a hospital-based, prospective clinical study to determine the incidence, risk factors, and outcome of extreme low birth weight and very low birth weight pre-term babies with retinopathy of prematurity (ROP) at the Sultan Qaboos University Hospital, Oman.

METHODS

All babies with a birth weight =/< 1500 g and gestational age =/< 32 weeks admitted in the Neonatal Unit, were screened for ROP between 4 to 6 weeks of age and staged according to the international classification and were followed up until complete vascularization of the retina. Fifty nine babies formed the study group.

RESULTS

The overall incidence of ROP was 25.4% (15 out of 59), of which 6 babies had severe ROP and underwent cryotherapy/laser. All babies with ROP had a birth weight < 1250 g and were born before 31 weeks of gestation.

CONCLUSION

ROP is a multifactorial disease, the immature retina of the pre-term baby being the primary factor. Incidence and severity was inversely proportional to birth weight and gestational age. Multiple logistic regression analysis showed that sepsis and total parenteral nutrition to be highly significant risk factors. Repeated blood transfusions, hypotension and congenital heart disease with left to right shunt were seen to be considerably associated with the development of ROP. A decrease in overall incidence and severity of ROP was observed in this study.

Retinopathy of prematurity: causation

The incidence of ROP is birth weight dependent and restricting therapeutic oxygen levels has dramatically reduced the incidence of ROP in infants of birth weight >1000 g. However, the incidence of ROP has remained high in very low birth weight (VLBW) infants and this appears to be related to these babies being more ill. Several risk factors have been identified in this group, however oxygen variability, rather than high levels, has been correlated with severity of disease in recent clinical and animal studies. Difficulties in defining 'normal' oxygen in this group has meant the optimal range of oxygen therapy has not yet been defined. Clinical studies are now underway using even lower oxygen therapy ranges. The impact this may have on ROP, neurological and respiratory outcomes will require further study.

The outcome of retinopathy of prematurity: screening for retinopathy of prematurity using an outcome predictive program

PURPOSE

The purpose of this study was to compare the calculated risk of progression to threshold retinopathy of prematurity (ROP) and risk of an unfavorable structural outcome using the computer program, RM-ROP, with the observed incidence for infants born at Jackson Memorial Hospital (JMH) and to determine how many children would have been treated unnecessarily if the threshold criteria for treatment were lowered on the basis of the clinical findings and RM-ROP risk calculations.

DESIGN

Noncomparative interventional case series.

PARTICIPANTS

All 292 surviving premature infants weighing 1250 g or less at birth and born at JMH between January 1, 1997, and December 31, 1998, were included in the study.

METHODS

Baseline demographic factors and data from sequential ophthalmic examinations were entered into the RM-ROP program for risk calculation. Infants reaching threshold disease received diode laser indirect photocoagulation of the avascular retina. Three-month follow-up was obtained for infants receiving laser treatment.

MAIN OUTCOME MEASURES

The development of threshold ROP and an unfavorable structural outcome, defined as a posterior retinal fold or posterior retinal detachment occurring within 3 months of threshold disease.

RESULTS

Thirty-eight eyes were diagnosed with threshold ROP, with 18 of 20 subjects having bilateral disease. Three-month posttreatment follow-up was obtained on all 20 children, with 19 having good structural outcomes. Thirty-two percent of eyes (12 of 38) reaching threshold never had a risk estimate greater than 0.10. However, only 6% of eyes (35 of 546) that did not reach threshold ever had a model predicted risk greater than 0.15. All right eyes with zone 1 prethreshold disease, 60% of those with zone 2 stage 2+ disease, and 23% with zone 2 stage 3 disease progressed to threshold ROP.

CONCLUSIONS

The similarity between the risk distributions for the Miami and the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity study indicates the similarity in the populations with respect to risk factors identified as important by the model. The Miami data validated the model, with eyes reaching threshold having higher risks than eyes that did not. Actual risk estimates for eyes reaching threshold can be small. Changing the threshold criteria for treatment on the basis of various clinical and computer-generated prethreshold risk levels in our population would have resulted in the unnecessary treatment of many infants who never progressed to threshold disease. In the Miami population, if the model were used to manage an individual subject, close attention would have to be paid to small differences in risk. Although the RM-ROP software program may be a useful tool for following premature infants with ROP, the clinical examination remains the "gold standard."

In vitro fertilisation and stage 3 retinopathy of prematurity

PURPOSE

To re-examine the risk of children born by assisted conception developing stage 3 retinopathy of prematurity (ROP) and to define whether the risk of ROP varies with the method of assisted conception.

METHODS

This was a retrospective study carried out between December 1995 and December 1998 of infants in a single neonatal unit serving the Brent and Harrow area of North West Thames requiring screening and treatment of ROP. The infants screened were identified from the ROP screening database. Those conceived by in vitro fertilisation (IVF) and other forms of assisted conception were identified by reviewing the neonatal notes and the maternal obstetric records. Birth weight, gestational age and the type of assisted conception were recorded. The presence or absence of any stage of ROP, its location and severity and the cases requiring treatment were recorded.

RESULTS

One hundred and seventy-nine infants fulfilled the screening criteria during this period. Acute ROP was detected in 32.4% (58 infants) and stage 3 ROP developed in 15.6% (28 infants). Twenty-one infants (11.7%) were born after assisted conception, with 12 (6.7%) being conceived by IVF. The others were conceived on clomiphene (8) or after intrauterine insemination (1). Assisted conception accounted for 21.4% of all those reaching stage 3 disease and 28.6% of those infants requiring treatment. Of the 12 infants conceived by IVF, 41.6% (5 infants) developed acute ROP which progressed to threshold ROP in all infants (100%). Of the assisted conception babies requiring treatment for ROP, 83.3% were conceived by IVF. The other child had been conceived on clomiphene. The gestational age and birth weight of the IVF infants reaching stage 3 ROP were 26.6 +/- 0.89 weeks and 937 +/- 170.2 g. The gestational age and birth weight in the rest of the infants reaching stage 3 ROP were lower than in those conceived by assisted conception (25.739 +/- 1.13 weeks and 735.29 +/- 117.70 g); however, this did not approach statistical significance (p = 0.35 and p = 0.13, respectively).

CONCLUSIONS

In this study 11.7% of the group requiring screening were conceived by assisted conception. Of all babies requiring treatment for ROP, 28.6% were born after assisted conception. Of the assisted conception group, 83.3% were conceived by IVF. Assisted conception using IVF rather than other techniques appears to be the major risk factor for the development of threshold ROP. We would advise increased vigilance when screening babies conceived by the IVF methods of assisted conception.

Threshold stage of retinopathy of prematurity: maternal and neonatal risk factors

BACKGROUND

The aim of this study was to review the maternal and neonatal risk factors associated with retinopathy of prematurity (ROP) and the threshold stage of the disease.

PATIENTS AND METHODS

In this prospective cohort study, all preterm infants of less than 1501 g birth weight were screened for ROP between January 1996 and December 1997 at the neonatal unit of the Maternity Hospital in Kuwait. The rate of the threshold stage of ROP, as well as risk factors associated with the disease, were identified.

RESULTS

A total of 234 babies were screened for ROP, of which 151 (64.5%) developed the disease and 34 (14.5%) had the threshold stage of ROP. Several factors were found to be associated with ROP and threshold ROP. Stepwise regression analysis revealed that low birth weight (P<0.002) and exposure to high oxygen concentration (P<0.0001) were independently associated with ROP. In addition, low birth weight (P<0.006), high oxygen concentration (P<0.003), and culture-proven sepsis (P<0.04) were found to be independent predictors of threshold ROP.

CONCLUSION

Apart from low birth weight and exposure to high oxygen therapy, which are well-documented risk factors of ROP, septicemia was also found to be associated with the threshold stage of ROP.

Results of screening low-birth-weight infants for retinopathy of prematurity

Retinopathy of prematurity (ROP) continues to be an important cause of potentially preventable blindness worldwide. The pattern of visual impairment from ROP in some middle-income countries--high rates affecting larger and more mature infants--resembles that seen in more developed countries two decades ago and has been called a "third epidemic" of the disease. Expert bodies in the United Kingdom and the United States have recently issued new guidelines for screening for ROP that utilize both birth weight and gestational age criteria. Studies in both countries suggest these criteria might be further revised to decrease time spent on screening without missing any significant disease. Population-based follow-up studies of extremely preterm infants suggest that although more preterm infants are surviving, with adequate screening and treatment, rates of blindness from ROP may be declining. Further information on the longer-term impact of ROP comes from a number of studies and particularly the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) study. The risk of both myopia and strabismus is increased with any and each higher stage of ROP. Evidence is emerging that laser therapy for threshold disease may be associated with better visual outcome than cryotherapy, although complications following the former remain a concern. The fight against ROP may be enhanced by new information on the pathogenesis, including possible genetic predisposition and the role of vascular endothelial growth factor.