Ankara University Faculty of Medicine neonatal retinopathy of prematurity in the intensive care unit evaluation of screened infants

Objective: Retinopathy of prematurity (ROP) is defined as a retinal vasoproliferative disease that affects premature infants. This study was conducted to investigate the need for retinopathy screening in premature infants aged ≤32-34 weeks in our unit, to compare the results with the determined screening guidelines and to evaluate the possible risk of the screening program. Secondarily, it was aimed to determine the incidence of ROP requiring treatment in screened infants, to examine the relationship of this rate with birth week and birth weight, and to determine the appropriate screening criteria. Materials and Methods: Our study was designed as a retrospective single-center study. The files of 425 infants who were under ≤32-34 weeks of age and who were screened for ROP between 2017 and 2021 in Ankara University Faculty of Medicine Neonatal Intensive Care Unit were evaluated, and ROP examination results with risk factors were recorded. Patients were grouped according to whether they developed ROP or not. The factors that may be associated with ROP were evaluated between groups as belonging to the prenatal, natal, postnatal stage. Multivariate logistic regression analysis was performed for the associated factors. Results: Of the 425 patients included in the study, 42% were female and 58% were male, with a mean gestational week (GH) of 30.71±2.54 weeks and a mean birth weight (BW) of 1550±550 g. ROP of any stage was detected in 90 infants (21.2%) and ROP was not observed in 335 infants (78.8%). The mean GH of the infants with ROP was 28.3±2.4 weeks and the mean DA was 1133±382 g. Of the 90 patients who developed ROP, 90% was under 32 weeks and 10% was between 32 and 34 weeks. Of the 90 patients who developed ROP, 77 (85.5%) had a BW of less than 1500 g and 13 (14.5%) had a BW of more than 1500 g. In patients under 34 weeks of age, when the group with ROP was compared with the group without ROP; BW, GH, birth height and head circumference and APGAR scores were lower in the group with ROP (p<0.001). Oxygen therapy, mechanical ventilation (MV) support, total parenteral nutrition (TPN) need and duration, necrotizing enterocolitis (NEC), prolongation of hospital stay, blood transfusion, respiratory distress syndrome (RDS), intracranial hemorrhage (ICC), patent ductus arteriosus (PDA), inotrope requirement, surfactant administration, sepsis history were statistically significant in patients who developed ROP (p<0.001). In multivariate logistic regression analysis, BW (OR=7.291), PDA (OR=2.619), invasive MV (OR=3.891) were identified as effective independent risk factors for ROP. Of the 90 patients with ROP, 80 (88.9%) had spontaneous regression without any treatment requirement, while 10 (11.1%) had ROP, which was an indication for treatment. All patients with ROP underwent laser photocoagulation therapy, while one patient underwent vitrectomy in addition. The mean GH of the treated infants was 25.50±1.89 weeks (23.1-29.0 weeks) and the mean BW was 747±158 g (range 525-1080 g). All except one (BW of 1080 g) of the patients who developed severe ROP and received treatment had <1000 g BW. All of the ROP patients requiring treatment had < 30 GW. The patient with the largest laser photocoagulation had a delivery week of 29 5/7 weeks and a BW of 1080 g. The oldest patient with ROP was 2170 g with 33 3/7 weeks. There were no serious ROP patients between 32-34 weeks and above ≥1500 g, but 9 (4.9%) patients had any stage ROP by screening. When the group with ROP developed below 32 weeks and the group with ROP developed over 32 weeks were compared, the group with ROP below 32 weeks had lower APGAR scores of 1 and 5 min, longer hospital stay, and higher MV rate (p<0.001). When the group that developed ROP at 32 weeks or more were compared with the ones that did not develop ROP; chorioamnionitis, maternal preeclampsia, PDA and ICC were defined as risk factors. In multivariate logistics regression analysis of patients below 32 weeks; BW (OR=7.727), early membrane rupture (EMR) (OR=6,039), invasive MV (OR=7,757) were identified as independent risk factors for ROP. Discussion and Conclusion: In the last 5 years (2017-2021), the incidence of ROP and the rate of ROP requiring treatment in our Neonatal Intensive Care Unit of Ankara University Faculty of Medicine were observed to be lower than in previous years. In our study, although patients requiring treatment had a smaller GW (<30 weeks) and BW (<1250 g), applying restricted screening criteria below 32 weeks missed patients who developed ROP at any stage. According to these results, screening of infants younger than 34 weeks of GH or 1700 g BW, as shown in the guideline of the TR-ROP screening guideline, does not miss any stage ROP patients, but does not provide any additional gain in our unit in terms of severe ROP. When screening for ROP in older premature babies, presences of PDA, EMR and invasive MV should be considered as risk factors. Key Words: Retinopathy of prematurity, screening criteria, birth weight, gestational week.