Screening for retinopathy of prematurity in a tertiary hospital in Istanbul: incidence and risk factors

Oxygenation Fluctuations Associated with Severe Retinopathy of Prematurity: Insights from a Multimodal Deep Learning Approach

Purpose

Retinopathy of prematurity (ROP) is one of the leading causes of blindness in children. Although the role of oxygen in the pathophysiology of ROP is well established, a precise understanding of the dynamic relationship between oxygen exposure ROP incidence and severity is lacking. The purpose of this study was to evaluate the correlation between time-dependent oxygen variables and the onset of ROP.

Design

Retrospective cohort study.

Participants

Two hundred thirty infants who were born at a single academic center and met the inclusion criteria were included. Infants are mainly born between January 2011 and October 2022.

Methods

Patient data were extracted from electronic health records (EHRs), with sufficient time-dependent oxygen data. Clinical outcomes for ROP were recorded as none/mild or moderate/severe (defined as type II or worse). Mixed-effects linear models were used to compare the 2 groups in terms of dynamic oxygen variables, such as daily average and the coefficient of variation (COV) fraction of inspired oxygen (FiO2). Support vector machine (SVM) and long-short-term memory (LSTM)-based multimodal models were trained with fivefold cross-validation to predict which infants would develop moderate/severe ROP. Gestational age (GA), birth weight, and time-dependent oxygen variables were used to develop predictive models.

Main Outcome Measures

Model cross-validation performance was evaluated by computing the mean area under the receiver operating characteristic (AUROC) curve, precision, recall, and F1 score.

Results

We found that both daily average and COV of FiO2 were associated with more severe ROP (adjusted P < 0.001). With fivefold cross-validation, the multimodal LSTM models had higher performance than the best static models (SVM using GA and 3 average FiO2 features) and SVM models trained on GA alone (mean AUROC = 0.89 ± 0.04 vs. 0.86 ± 0.05 vs. 0.83 ± 0.04).

Conclusions

The development of severe ROP might not only be influenced by oxygen exposure but also by its fluctuation, which provides direction for future study of pathophysiological factors associated with severe ROP development. Additionally, we demonstrated that multimodal neural networks can be a method to extract useful information from time-series data, which may be a valuable methodology for the investigation of other diseases using EHR data.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Risk factors in the development of retinopathy of prematurity: A 10-year retrospective study

OBJECTIVE

To evaluate Retinopathy of Prematurity (ROP) rate and risk factors in a large cohort of preterm newborns.

METHODS

Single center retrospective study. All preterm inborn hospitalized at the Neonatal Intensive Care Unit of the Policlinico of Catania from January 1, 2009 till December 31, 2018, were included. ROP stage and location, treatments required, maternal and infant risk factors were evaluated.

RESULTS

Medical records of 898 preterms were retrospectively examined (mean gestational age 32.9 ± 2.3 weeks). Of them 149 (16.6 %) developed bilateral ROP (92 stage 1, 44 stage 2 and 13 stage 3); 66 (7.3 %) received bilateral laser treatment. Six eyes of three patients affected by zone I ROP 1, with plus persistence 15 days after an optimal laser treatment, also received intravitreal ranibizumab injection. Risk factors for ROP development were gestational age (GA) (p < 0.001), birthweight (p < 0.001), assisted ventilation duration (p < 0.001), multiple birth (p = 0.003), erythropoietin (EPO) administration (p = 0.005) and persistence of tunica vasculosa lentis. The decision-tree analysis showed gestational age as the most significant predictive factor (P < 0.001); secondary predictive factors were EPO administration (p = 0.001) in newborns 29-31 weeks GA and birthweight lower than 2090 g (p < 0.001) in 32-34 weeks GA; in this latter group patent ductus arteriosus (PDA) was a tertiary predictive factor (p = 0.043).

CONCLUSIONS

In our study ROP incidence was 16,6 %; 7.3 % of the patients required laser treatment. Besides well-known factors, such as GA and birthweight, other factors like duration of assisted ventilation, EPO, multiple births, PDA, tunica vasculosa lentis persistence should be considered to tailor ophthalmic evaluation and follow-up.

Factors associated with refractive outcome in children treated with bevacizumab for retinopathy of prematurity: the importance of retinal vascularization

PURPOSE

To evaluate the factors that may be associated with refractive outcome in eyes treated with intravitreal bevacizumab (IVB) injection for retinopathy of prematurity (ROP).

METHODS

Retrospective case series. Refractive outcomes of 181 infants who were treated with primary IVB for Type I ROP or aggressive ROP, were retrospectively evaluated. According to the pretreatment retinal vascularization, eyes were classified into zone I, zone I-zone II, and zone II groups. The first year, third year, and final refractive error were analyzed. Univariate logistic regression test was performed to evaluate the effect of factors on the development of ≥ 1 diopter (D) myopia.

RESULTS

At the final examination, the mean age was 22.9 ± 10.9 months. The zone II group was more hyperopic than the zone I-zone II and zone I zone groups (P = 0.001). Of the 331 eyes, 17 eyes (5.1%) had high myopia, 50 eyes (15.1%) had low myopia, and 83 eyes (25.1%) had emmetropia. During follow-up, 110 (33.2%) eyes underwent laser treatment. Gestational age, birth weight, neonatal intensive care unit type, the presence of additional laser treatment, number of injections, the type of ROP, and the dose of IVB were not associated with the development of ≥ 1 D myopia. The pretreatment and prelaser retinal zones were associated with the development of ≥ 1 D myopia.

CONCLUSION

The most important factors affecting the refractive outcome in infants who underwent primary IVB treatment was the extent of pretreatment and prelaser retinal vascularization.

Quantification of Early Neonatal Oxygen Exposure as a Risk Factor for Retinopathy of Prematurity Requiring Treatment

Purpose

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness related to oxygen exposure in premature infants. Since oxygen monitoring protocols have reduced the incidence of treatment-requiring ROP (TR-ROP), it remains unclear whether oxygen exposure remains a relevant risk factor for incident TR-ROP and aggressive ROP (A-ROP), a severe, rapidly progressing form of ROP. The purpose of this proof-of-concept study was to use electronic health record (EHR) data to evaluate early oxygen exposure as a predictive variable for developing TR-ROP and A-ROP.

Design

Retrospective cohort study.

Participants

Two hundred forty-four infants screened for ROP at a single academic center.

Methods

For each infant, oxygen saturations and fraction of inspired oxygen (FiO₂) were extracted manually from the EHR until 31 weeks postmenstrual age (PMA). Cumulative minimum, maximum, and mean oxygen saturation and FiO₂ were calculated on a weekly basis. Random forest models were trained with 5-fold cross-validation using gestational age (GA) and cumulative minimum FiO₂ at 30 weeks PMA to identify infants who developed TR-ROP. Secondary receiver operating characteristic (ROC) curve analysis of infants with or without A-ROP was performed without cross-validation because of small numbers.

Main Outcome Measures

For each model, cross-validation performance for incident TR-ROP was assessed using area under the ROC curve (AUC) and area under the precision-recall curve (AUPRC) scores. For A-ROP, we calculated AUC and evaluated sensitivity and specificity at a high-sensitivity operating point.

Results

Of the 244 infants included, 33 developed TR-ROP, of which 5 developed A-ROP. For incident TR-ROP, random forest models trained on GA plus cumulative minimum FiO₂ (AUC = 0.93 ± 0.06; AUPRC = 0.76 ± 0.08) were not significantly better than models trained on GA alone (AUC = 0.92 ± 0.06 [P = 0.59]; AUPRC = 0.74 ± 0.12 [P = 0.32]). Models using oxygen alone showed an AUC of 0.80 ± 0.09. ROC analysis for A-ROP found an AUC of 0.92 (95% confidence interval, 0.87–0.96).

Conclusions

Oxygen exposure can be extracted from the EHR and quantified as a risk factor for incident TR-ROP and A-ROP. Extracting quantifiable clinical features from the EHR may be useful for building risk models for multiple diseases and evaluating the complex relationships among oxygen exposure, ROP, and other sequelae of prematurity.

Effect of red blood cell transfusion on the development of retinopathy of prematurity: A systematic review and meta-analysis

BACKGROUND

The effect of red blood cell (RBC) transfusion on retinopathy of prematurity (ROP) is difficult to establish, because ROP may also be influenced by other factors. Therefore, we carried out a systematic review and meta-analysis to explore the relationship between RBC transfusion and the development of ROP.

METHODS

The PubMed, Embase, Cochrane Library and Web of Science databases were searched from their inception to September 1, 2019. Observational studies that reported the relationship between RBC transfusion and ROP after adjusting for other potential risk factors were included. The combined result was analyzed by a random effect model. Heterogeneity and publication bias were tested, and sensitivity analysis was performed.

RESULTS

Of the 2628 identified records, 18 studies including 15072 preterm infants and 5620 cases of ROP were included. A random effect model was used and revealed that RBC transfusion was significantly associated with ROP (pooled OR = 1.50, 95% CI: 1.27-1.76), with moderate heterogeneity among the included studies (I2 = 44.2%). Subgroup analysis indicated that RBC transfusion was more closely related to ROP in the group with a gestational age (GA) ≤32 weeks (OR = 1.77, 95% CI: 1.29-2.43) but not in the groups with a GA ≤34 weeks (OR = 1.36, 95% CI: 0.85-2.18) or a GA <37 weeks (OR = 1.25, 95% CI: 0.86-1.82). No obvious publication bias was found based on the funnel plot and Egger's test. Removing any single study did not significantly alter the combined result in the sensitivity analysis.

CONCLUSIONS

Our study revealed that RBC transfusion is an independent risk factor for the development of ROP, especially in younger preterm infants. However, there seemed to be no evidence to support an effect of RBC transfusion on ROP in older groups. Further studies addressing this issue in older preterm neonates are warranted.

Aggressive Posterior Retinopathy of Prematurity Treated with Intravitreal Bevacizumab: Late Period Fluorescein Angiographic Findings

OBJECTIVE

To evaluate vascularization end limit of the peripheral retina and describe vascular development patterns of patients at the late period with aggressive posterior retinopathy of prematurity (APROP) who were treated with a single intravitreal injection of bevacizumab.

METHODS

All patients were examined with RetCam III and fluorescein angiography (FA) within 90-100 gestational week. The vascularization end limit according to the zones and vascular structural abnormalities were noted.

RESULTS

A total of 116 eyes of 58 patients were included. The mean gestational age and birth weight were 28.31 ± 2.5 (23-33) weeks and 1156.29 ± 386.38 (360-2300) g, respectively. The mean age at the time of FA was 95.09 ± 3.8 (90-100) weeks. According to the vascular termini, four eyes (3.4%) were in zone II posterior, 30 eyes (25.8%) were in zone II anterior, 22 eyes (18.9%) were in zone III with a distance of > 2 disc diameter (DD) from ora serrata, and 60 eyes (51.7%) were in zone III with a distance of < 2 DD from temporal ora serrata. Abnormal vascular findings were detected in 86.2% of patients (100/116 eyes) including circumferential vessels (43.1%), abnormal vascular branching (25.9%), closely packed vascular shunts (6.8%), and vascular leakage (10.3%).

CONCLUSION

FA gives us quantitative data for treatment decision at late period of APROP patients treated with bevacizumab. Fluorescein leakage and persistent avascular areas still detected at FA at 90-100 gestational weeks increase the risk for late complications. FA can detect the abnormalities that can not be detected via indirect ophthalmoscope and be useful for follow-up and further treatments of APROP.

Retinopathy of prematurity in Africa: a systematic review

Purpose: Retinopathy of prematurity (ROP) is widely regarded worldwide as a major cause of childhood blindness, however until recently the disease has not been recognized in most of the African continent. As a result of changing economic conditions, there is growing evidence that the population at risk for ROP in Africa is increasing. This report aims to summarize the published literature on ROP from Africa. Methods: We performed a systematic literature review of the English and French online literature databases by applying a general search strategy initially on May 1, 2017 with repeat inquiry on May 20, 2018. Search phrases included multiple variants of terms including "ROP", "retinopathy of prematurity", in conjunction with each of the individual 54 recognized sovereign African states. Findings: A total of 25 individual studies from six African nations were identified: South Africa (10), Egypt (7), Nigeria (4), with the nations of Sudan, Rwanda, and Kenya each having one respective study. Two countries (South Africa and Kenya) have developed national ROP policies for primary and secondary prevention. Summary: Review of the published literature suggests that ROP is emerging in Africa, however, there are published data from 6/54 (11%) African nations. Blindness from ROP is often preventable with appropriate primary and secondary prevention. This report provides compelling evidence that these efforts should be undertaken to implement and evaluate regionally appropriate ROP prevention programs in a growing number of African countries.

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.

Clinical Outcomes of High-Risk Infant Follow-Up Program in a Tertiary Care Centre

BACKGROUND

High-risk infant follow-up (HRIF) program is necessary for early detection, timely intervention, and promotion of health outcomes in vulnerable infants, ethically. The present study was carried out to assess the clinical outcomes of the HRIF Program in Alzahra hospital as a tertiary care centre, in Iran.

MATERIALS AND METHODS

In this cohort study, 5840 neonates were born at Alzahra hospital, from June 1, 2011 to 30th February 2012. Among those who were admitted to neonatal intensive care unit (NICU), 253 infants were recruited by census according to HRIs criteria. After doing necessary measurements and family education, information was recorded in HRI health certificate and then entered in the access database for analysis.

RESULTS

From 253 eligible HRIs registered, 241 (95%) infants attended the follow-up clinic after discharge. A total of180 cases were recalled for further visits, 110 of which attended the clinic. Anthropometric indices had an increasing trend in the first 6 months of life. There was no significant relation between ages and stages questionnaire (ASQ) results and infant birth weight, height, and head circumference. The ratios of intraventricular hemorrhage (IVH) and retinopathy of prematurity (ROP) were 8.7% and 3.1%, respectively. The incidence of congenital hypothyroidism was 2:341 in HRIs.

CONCLUSIONS

Although some outcomes, such as ROP, improved in our study compared to similar studies, the findings indicate an impairment of the current follow-up processes and highlight the necessity to modify the current HRIF program. Ethically, we insist on integrating HRIF program in child health services to promote early childhood development.

Characteristics of Severe Retinopathy of Prematurity in Infants with Birth Weight above 1500 Grams at a Referral Center in Turkey

PURPOSE

To demonstrate the clinical characteristics and treatment outcomes of severe retinopathy of prematurity (ROP) in preterm infants with birth weight (BW) above 1500 g in Turkey.

METHODS

A retrospective review of 5920 ROP records was performed in Zeynep Kamil Maternity and Children's Diseases Training and Research Hospital. The records were obtained from ROP treatment center of the same institute between 2011 and 2016. The data comprised the demographic and clinical characteristics including, gestational age, BW, systemic risk factors, zone and stage of ROP, ROP type, treatment modality, treatment outcomes and inborn/outborn status of the babies.

RESULTS

A total of 36 infants (71 eyes) with severe ROP and BW> 1500 g were retrieved. There were 30 infants (83.3%) with type 1 ROP and 6 infants (16.7%) with aggressive posterior ROP (APROP). 3 infants (8.3%) were born at our hospital whereas 33 (91.7%) were referred from outer private neonatal intensive care unit (NICU) centers. Zone I APROP was detected during the initial screening. 21 infants (58.3%) underwent laser treatment while 15 (41.7%) received intravitreal bevacizumab (IVB) injections. No unfavorable structural outcome was observed following either treatment modality.

CONCLUSION

Severe ROP may occur in heavier preterm infants. Laser treatment and IVB injections were useful in selected cases. Presence of APROP at first examination suggests an earlier screening in heavier babies. Standardization of private NICU centers as well as establishing a national ROP protocol is necessary in Turkey.

Retinopathy of prematurity screening criteria in Iran: new screening guidelines

OBJECTIVE

To test the applicability of existing retinopathy of prematurity (ROP) guidelines on Iranian patients and to develop novel ROP screening criteria in Iran.

METHODS

Both eyes of 1932 infants born ≤37 weeks of gestation and/or weighting ≤3000 g were included in this prospective cohort study that was conducted across nine neonatal intensive care units and a tertiary eye hospital ROP clinic. The patients were examined for ROP and the need for treatment (type 1 ROP or worse). All the patients were screened 4 weeks after birth or at 31 weeks of postmenstrual age, whichever was later. The patients were followed until retinal vascularisation was completed or the patients reached 50 weeks of gestational age (GA) without prethreshold ROP. A receiver operating characteristic curve was used to determine the best screening criteria for ROP. Screening criteria from other countries were applied to our patient data to determine their ability to appropriately detect ROP.

MAIN OUTCOME MEASURE

Patients with ROP requiring treatment.

RESULTS

The mean GA±SD and birth weight (BW)±SD of the screened patients were 32±2.7 weeks and 1713±516 g, respectively. Using criteria of GA≤32 weeks or BW ≤2000 yielded sensitivity and specificity of 100% and 26.7%, respectively, for treatment requiring ROP regardless of clinical comorbidities. Using screening recommendations of American Academy of Pediatrics would miss 25.4% of ROP and 8.4%ROP requiring treatment in our cohort.

CONCLUSIONS

Other countries screening recommendations would result in a significant amount of missed cases of treatment requiring ROP when applied to Iran. As a result, we have proposed new guidelines for premature babies in Iran.

Retinopathy of prematurity: incidence, risk factors, and evaluation of screening criteria

BACKGROUND/AIM

The goal of this study was to investigate the incidence of retinopathy of prematurity (ROP) and the relationship between risk factors and disease in premature newborns in our neonatal intensive care unit.

MATERIALS AND METHODS

A total of 219 premature subjects were retrospectively evaluated for retinopathy. Demographic information, clinical data, and risk factors were reviewed.

RESULTS

The gestational ages of the infants included in the study ranged between 25 and 36 weeks, and the birth weights ranged between 670 and 4460 g. In this study, the incidence of ROP was 20.1% (44) in preterm infants: 16 had stage 1 (36.4%), 15 had stage 2 (34.1%), 11 had stage 3 (25%), 1 had stage 4 (2.3%), 1 had stage 5 (2.3%), and 6 had plus (+) disease (7.2%). The risk factors associated with the development of ROP included low birth weight, ventilation treatment, bronchopulmonary dysplasia, and maternal preeclampsia. The risk factors were analyzed with logistic regression analysis. The odds ratios were 5.952 (95% confidence interval [CI]: 2.030-17.447), 20.070 (95% CI: 4.213-95.600), 5.879 (1.916-18.037), and 3.200 (95% CI: 1.002-11.535), respectively.

CONCLUSION

In this study, birth weight, ventilation treatment, bronchopulmonary dysplasia, and maternal preeclampsia were the most important risk factors for the development of ROP.

Clinical features of infants treated for severe retinopathy of prematurity: 8-yearstudy from a large tertiary neonatal intensive care unit in Turkey

BACKGROUND/AIM

The aim of this study was to report the gestational age (GA) and birth weight (BW) distribution of premature babies who needed treatment for retinopathy of prematurity (ROP) and to assess the timing of the treatment.

MATERIALS AND METHODS

The records of 9008 infants who were screened for ROP were examined and 556 infants who underwent laser therapy for ROP were reviewed. Sex, GA, BW, postnatal age, and postmenstrual (PM) age at the time of laser therapy were recorded. The babies were classified as in-born (Group 1) and out-born infants (Group 2).

RESULTS

The mean GA was 27.3 weeks (range: 22-33 weeks) and the mean BW was 991.1 g (range: 520-2160 g). Of the treated infants, 7.0% were born later than 32 weeks and 8.3% were born over 1500 g. The mean postnatal age was 9.48 weeks (range: 5-22 weeks) and the mean PM age was 36.72 weeks (range: 29-48 weeks) at the time of treatment. Mean BWs and GAs were significantly higher and the mean postnatal age at the time of laser therapy was significantly earlier in Group 2.

CONCLUSION

Infants with severe ROP had a wider range of BWs and GAs compared to those from developed countries and earlier treatment was needed for out-born infants.

Natural history of retinopathy of prematurity: two-year outcomes of a prospective study

PURPOSE

To investigate the 2-year outcomes of the natural history of retinopathy of prematurity (ROP) in Taiwan.

METHODS

A prospective study was conducted at two tertiary medical centers. Premature infants were screened and examined for ROP. The postmenstrual ages of developing each stage of ROP and the associated risk factors were recorded.

RESULTS

A total of 698 infants were included. The incidences of ROP and treatment-requiring ROP in all patients with ROP were 29.7% and 37.2%. When only including patients with birth weight of 1,250 g or less, the incidences were 62.2% and 39.1%, respectively. In patients with ROP with birth weight over 1,250 g, 25% of them developed treatment-requiring ROP. The median postmenstrual ages for the development of Stage 1, Stage 2, and Type 1 ROP were 33.0, 34.0, and 34.7 weeks, respectively. Gestational age at birth and birth weight were the most important factors associated with treatment-requiring ROP (hazard ratios of 0.3 and 0.6).

CONCLUSION

Our hospital-based study reveals an earlier postmenstrual age of developing ROP in this Asian population than in the Early Treatment for ROP study. Infants with birth weight over 1,250 g could still develop treatment-requiring ROP. Suboptimal oxygen control, different genetic dispositions among different races, inconsistencies in ROP diagnosis, and earlier screening might account for such a phenomenon.

Incidence and severity of retinopathy of prematurity in Turkey

BACKGROUND

The purpose of this study was to estimate the current incidence of retinopathy of prematurity (ROP) and the need for treatment in preterm infants in Turkey.

METHODS

The study included preterm infants who had been screened for ROP between 2011 and 2013 in 49 neonatal intensive care units. Infants with birth weight (BW) ≤1500 g or ≤32 weeks' gestational age and those with BW >1500 g or >32 weeks' GA with an unstable clinical course were included. The incidence of any ROP or severe ROP and treatment modalities were determined.

RESULTS

The study population included 15 745 preterm infants: 11 803 (75%) with GA ≤32 weeks, and 3942 (25%) with GA >32 weeks. Overall, 30% were found to have any stage of ROP, and 5% had severe ROP. Severe ROP was diagnosed in 8.2% of infants with BW ≤1500 g and 0.6% of infants with BW >1500 g. Of all infants diagnosed with ROP, 16.5% needed laser photocoagulation, and 20 patients born at >32 weeks' GA required this treatment modality. Vitroretinal surgery was performed in 28 infants with severe ROP: 23 with GA ≤28 weeks and 5 with GA 29-32 weeks.

CONCLUSIONS

The findings of our study have the important implication that more mature babies are at risk of severe ROP requiring treatment. An effective programme for detecting and treating ROP should be established in Turkey.

TRIAL REGISTRATION NUMBER

orcid.org/0000-0002-1329-2167.

Retinopathy of prematurity: a study of prevalence and risk factors

Background:

Retinopathy of prematurity (ROP) is a serious complication of prematurity treatment and can lead to blindness unless recognized and treated early.

Objective:

The objective was to estimate the prevalence of ROP in preterm infants in the Neonatal Intensive Care Unit (NICU), to identify the risk factors which predispose to ROP, and to assess the outcome of these cases.

Materials and Methods:

A ROP prospective screening survey was performed enrolling all prematures admitted to the NICU from January 2009 to December 2010, with a gestational age of 32 weeks or less at birth and a birth weight of 1500 g or less. Infants whose gestational age was >32 weeks or birth weight was >1500 g were included if they were exposed to oxygen therapy for more than 7 days. A total of 172 infants (84 males and 88 females) had retinal evaluation by indirect ophthalmoscopy from the fourth postnatal week and followed up periodically. Perinatal risk factors for ROP were assessed using univariate and multivariate analysis. Infants who progressed to stage 3 ROP were given laser therapy.

Results:

Out of the studied 172 infants, 33 infants (19.2%) developed ROP in one or both eyes; 18 (54.5%) cases stage 1, 9 (27.3%) cases stage 2, and 6 (18.2%) cases stage 3. None of the studied neonates presented ROP at stages 4 or 5. The six cases diagnosed as ROP stage 3 underwent laser ablative therapy. Univariate analysis showed that there was a significant relationship between the occurrence of ROP and gestational age (P = 0.000), sepsis (P = 0.004), oxygen therapy (P = 0.018), and frequency of blood transfusions (P = 0.030). However, an insignificant relationship was found between the occurrence of ROP and sex, mode of delivery, birth weight, respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, hypotension, phototherapy, duration of oxygen therapy, mechanical ventilation, and CPAP (all P > 0.05). Gestational age, sepsis, oxygen therapy, and frequency of blood transfusions remained significant variables after logistic regression analysis.

Conclusion:

The prevalence of ROP in this study was 19.2%; low gestational age, sepsis, oxygen therapy, and frequent blood transfusions were significant risk factors for ROP. Laser was effective in treatment and decreasing the progression of ROP. As this is a unit-based study, a comprehensive countrywide survey on ROP in Egypt is recommended to determine any regional differences in disease prevalence.

The Association between Serum Homocysteine Levels and Retinopathy of Prematurity

Objective:

To evaluate the relationship between serum total homocysteine levels and retinopathy of prematurity (ROP).

Methods:

This prospective case-control study involved premature infants diagnosed with ROP 4 weeks after birth (cases); controls were premature infants not developing ROP during follow-up. Fasting serum total homocysteine concentrations were determined in all participants 4 weeks after birth, using high performance liquid chromatography.

Results:

A total of 45 and 35 infants were included in the case and control groups, respectively. The mean ± SD (range) serum total homocysteine levels were 10.36 ± 1.72 μmol/l (7.45 - 14.84) in infants with ROP and 8.41 ± 2.12 μmol/l (5.56 - 13.90) in controls. This difference was statistically significant. Mean ± SD total homocysteine levels were higher in infants with more severe ROP (11.45 ± 1.76 μmol/l) compared with mild ROP (9.92 ± 1.56 μmol/l).

Conclusions:

Elevated serum total homocysteine levels are associated with the development of ROP in premature infants. Further studies with larger patient populations are required, to improve understanding of the relationship between homocysteine and ROP development.