ObjectiveTo retrospectively analyze incidence and trends of retinopathy of prematurity (ROP) from 2004 to 2013 in Shenzhen. MethodsA total of 9100 preterm children (5401 males, 3699 females) were screened for ROP in Shenzhen from January 2004 to June 2013 using binocular ophthalmoscope or RetCam Ⅱ. First examination was performed from 4-6 weeks after birth. The birth weight was 520-2990 g with an average of (1710±410) g.The gestational age were 24-36 weeks with an average of (31.57±1.99) weeks. The gestational age of 208 children were <28 weeks, 3608 children were 28-32 weeks, 3553 children was 33-34 weeks, 1731 children was >34 weeks. The ocular findings were recorded according to the International Classification of ROP and The Early Treatment for ROP. Only the more aggressive eye of bilateral asymmetrical cases was counted for statistical purpose, and the cases required surgeries were defined as severe cases. The 10 years period was divided into first phase (2004-2008) and second phase (2009-2013). The incidence of ROP and severe ROP of these two phases was compared and statistics was analyzed. ResultsIn the past 10 years, the overall incidence of ROP and sever ROP in Shenzhen was 12.49% and 4.99% in this screen. The children were divided into 4 groups according to the birth weight, the ROP incidences of birth weight <1000 g, 1000-1499 g, 1500-1999 g and ≥2000 g were 62.62%, 28.40%, 11.34% and 3.63% respectively. The severe ROP incidences were 34.95%, 12.21%, 3.73% and 0.49% respectively in these birth weight groups. The children were divided into 4 groups according to gestational weeks, the ROP incidences of gestational age <28 weeks, 28-32 weeks, 33-34 weeks and >34 weeks were 67.31%, 25.27%, 7.22% and 3.87% respectively. Severe ROP incidences were 37.02%, 10.71%, 1.79% and 0.68% in these gestational age groups respectively. ROP and severe ROP incidences were decreased from 14.64% at first phase to 11.47% at second phase, and from 6.52% at first phase to 4.26% second phase respectively, the differences were statistical significant (χ2=26.96, 26.61; P<0.05). ROP and severe ROP incidence in <1000 g birth weight group at second phase were much less than the first phase (χ2=13.676, 5.271; P<0.05). In <28 weeks gestational age group, the ROP incidence was the same in first phase and second phase (χ2=0.843, P>0.05), but the severe ROP incidence at second phase was much less the first phase (χ2=4.757,P<0.05). ConclusionFrom 2004 to 2013, the incidences of ROP and severe ROP have decreased significantly in Shenzhen.
ObjectiveTo observe the expression of CD147, matrix metalloproteinases-2 (MMP-2) and vascular endothelial growth factor (VEGF) in a rat model of oxygen induced retinopathy (OIR). MethodsEighty-four neonatal Wistar rats were divided into two groups randomly, the hyperoxia group (n=42) and the control group (n=42). Oxygen induced retinopathy was established in the hyperoxia group, the control group was raised in room air. Wholemonts were prepared from postnatal day (p) 7 and 14 rat retina to observe retinal vascular morphology. The number of endothelial cells to break through the internal limiting membrane was counted from p14 retinal paraffin sections. Expression of CD147, MMP-2 and VEGF protein levels was analyzed by immunohistochemistry on p12, p14, and p16 retinal sections. At the meantime, correlation between CD147 and MMP-2, VEGF was analyzed by two-way analysis of variance (ANOVA) test. ResultsAt p7, the retinal vasculature of the control group was radial distributed with large caliber. In OIR group, there were vasoconstriction, large area of avascular zone and a few small areas of vascular network. At p14, the normal untreated rat had interwoven retinal vasculature, but in OIR group, the retinal vasculature was expanded and tortuous, and forming lots of neovascular cluster in the boundary of the perfusion and non-perfusion regions resulting exudation and hemorrhage. At p14, the endothelial cell nuclei breakthrough the internal limiting membrane was (1.30±1.26) and (19.70±3.56) respectively in control and OIR group, the difference was statistically significant (t=21.813, P<0.01). Immunohistochemical staining showed that CD147, MMP-2, VEGF expression was low in control group but high in OIR group. From p12 to p16, CD147, MMP-2 and VEGF protein expression increased in OIR retinas compared with control samples(p12:t=5.612, 4.122, 4.955; P<0.01. p14:t=11.390, 8.047, 12.176; P<0.01. p16:t=6.355, 4.422, 5.110; P<0.01). ConclusionCD147, MMP-2 and VEGF were highly expressed in the rat model of oxygen induced retinopathy.
The exact pathophysiological mechanisms of retinopathy of prematurity (ROP) remain elusive. The risk factors of ROP include excessive oxygen therapy, malnutrition, infection and inflammation. Among the factors above, the effect of inflammation on ROP has received more attention. TNF-α is a biological active protein which is involved in neovascularization and inflammation. It may play a role in the development of ROP. This review summarized the studies on the association between TNF-α and ROP in recent years, so as to provide a new way to further study the pathogenesis and treatment methods of ROP.
ObjectiveTo investigate the clinical risk factors of preterm infants and its severity in premature infants with bronchopulmonary dysplasia (BPD) with retinopathy of prematurity (ROP).MethodsRetrospective clinical study was performed. A total of 126 preterm infants with BPD in the Neonatal Department of the Affiliated Hospital of Qingdao University from January 2016 to December 2018 were enrolled in the study. Among them, 69 were males and 57 were females, whose gestational age＜32 weeks and birth weight＜1500 g. BPD grades Ⅰ, Ⅱ, and Ⅲ were 63, 40, and 23 cases respectively. According to the presence or absence of ROP, children were divided into ROP group and non-ROP group, with 48 (38.1%) and 78 (61.9%) cases respectively. The differences of clinical data between the two groups were compared and analyzed. Quantitative data comparison between groups was performed by t test, and count data comparison was performed by χ2 test. The risk factors of ROP in BPD premature infants were analyzed by multi-factor logistics regression. The correlation between BPD severity and ROP severity was tested by Spearman rank correlation test.ResultsCompared with the non-ROP group, the ROP group had a smaller gestational age (t=5.988), lower birth weight (t=7.371), higher the application rate of oxygen concentration＞30% (duration of service＞24 h), high rate (χ2=17.244) and longer noninvasive ventilation time (t=－7.139), the differences were statistically significant (P＜0.05). In the logistic regression model, the noninvasive ventilation time was the risk factor for ROP in preterm infants with BPD (OR≈1.054, P＜0.05), while gestational age and birth weight were importantly protective factors for ROP in preterm infants with BPD (OR≈0.938, 0.996; P＜0.05). The results of the correlation analysis found that the severity of BPD was significantly positively correlated with the severity of ROP. As the severity of BPD increased, the severity of ROP increased, and the difference was statistically significant (rs=0.306, P＜0.035).ConclusionsFetal gestational age, low birth weight, hyperoxia, and long-term non-invasive mechanical ventilation are the main risk factors for ROP in preterm infants with BPD. The severity of BPD is positively correlated with the incidence and severity of ROP.
ObjectiveTo investigate the incidence and risk factors of retinopathy of prematurity (ROP) in extremely preterm infants (EPI) before 28 weeks of gestation during 8-years period.MethodsA retrospective study. From January 1, 2011 to December 31, 2018, 300 EPI infants with a gestational age of less than 28 weeks admitted to the neonatal intensive care unit (NICU) of Tianjin Central Hospital of Gynecology Obstetrics were included in the study. EPI birth gestational week (GA), birth weight (BW), gender and other basic information, as well as neonatal respiratory distress syndrome, oxygen (≥10 d), bronchopulmonary dysplasia (BPD) and other hospitalizations and complications were recorded. According to ROP international classification standards, ROP was staged. Severe ROP was defined as ROP that requires treatment. The screening start time, screening interval, and intervention time of all children tested were carried out in accordance with the requirements of the “Guidelines for Screening Retinopathy of Prematurity” until the end of follow-up. The most severe ROP during the follow-up of each examined child was recorded as the final screening result of the examined child, and those with asymmetric eyes with the screening results of the severe side of the diseas was recorded. A retrospective analysis of the overall incidence of EPI ROP showed the incidence of severe ROP, and the first and second stages of EPI ROP during the 8 years (from January 1, 2011 to December 31, 2014, and January 1, 2015 to December 31, 2018), changes in the rate of severe illness. Logistic regression analysis was used to screen independent risk factors for severe ROP.ResultsAmong 300 EPI infants, the average GA was (26.7±1.8) weeks; the average BW was (993.3±178.7) g. Two hundred and five infants (68.3%) were diagnosed with ROP, 116 (56.6%), 57 (27.8%), and 32 (15.6%) infants of stage Ⅰ, Ⅱ, and Ⅲ disease, respectively. There were no infants of stage IV and V. There were 30 infants (14.6%) with additional lesions and 59 infants (19.7%) with severe ROP requiring treatment. With the increase of GA (χ2=52.391, 44.521; P=0.000, 0.000) and BW (χ2=43.772, 26.138; P=0.000, 0.000), the incidence of EPI ROP and the incidence of severe ROP decreased significantly. From 2011 to 2018, the number of people surviving EPI obviously increased, especially those with small GA (26 weeks) and low BW (750 g). The average GA of the second stage EPI was lower than that of the first stage, the difference was statistically significant (t=2.243, P=0.026); the average BW of the second stage EPI was lower than the first stage, the difference was not statistically significant (t=1.428, P=0.154). The incidence of ROP in the second stage EPI was slightly higher than that in the first stage, and the incidence of severe ROP was lower than that in the first stage, the difference was not statistically significant (χ2=1.069, 1.723; P=0.301, 0.189). Multivariate logistic regression analysis showed that GA＜27 weeks (β=－2.584, P=0.032), maternal chorioamnionitis (CA) (β=－0.935, P=0.038) and BPD (β=－1.432, P=0.001) was an independent risk factor for severe ROP.ConclusionsThe incidence of EPI ROP and severe ROP are 68.3% and 19.7%, respectively. From 2011 to 2018, the number of survivors of EPI obviously increase, and those with small GA and low BW increase significantly; however, the incidence of ROP and severe ROP remaine stable. GA, CA and BPD are independent risk factors for severe ROP.