Clinical Analysis of Pathogenic Factors and Screening Strategy for Retinopathy of Prematurity
|Keywords||Retinopathy of prematurity Screening criteria Screening|
Objective:To investigate retinopathy of prematurity (ROP) detection in this region, discuss clinical features and relevant risk factors of ROP in premature babies, and to explore screening standards suitable for local neonatal intensive care unit (NICU).Methods:Premature infants with birth weight≤2000 grams or gestational age≤34 weeks came to Jinan Maternity and Child Care Hospital from January 2007 to December 2010 were screened. The first screening was made at 4-6 weeks after birth or corrected gestational age 32 weeks. All infants were examined by indirect ophthalmoscopy after mydriasis with 0.5% tropicamide and 0.5% epinephrine eye drops (Mydrin). The peripheral retina was observed under local anaesthesia with 0.4% Oxybuprocaine Hydrochloride Eye Drops and compressing with a sclera compressor. Gestational age, birth weight, oxygen inhalation mode, corrected gestational age, and fundus situation of all infants were recorded. All infants were divided into normal fundus group and ROP group according to their fundus status. Datum of both groups were analyzed with t test of measurement data orχ2 test of enumeration data. The detection of ROP was supposed to be a dependent variable (ROP=1, normal=0); and birth weight, gestational age, oxygen inhalation, multiparity, hyperbilirubinemia, surfactant, intrauterine hypoxia, anemia, respiratory distress, acidosis, preeclampsia during pregnancy and placental abruption were supposed to be independent variables, and were analyzed with Multivariable Logistic Regression method. The difference was considered to be statistical significant if P< 0.05. In the end, we compared the screening outcomes with American standard (birth weight< 1500 grams or gestational age< 28 weeks), English standard (birth weight <1500 grams or gestational age< 31 weeks), German, French, Dutch, and Swedish standard (birth weight<1500 grams or gestational age< 32 weeks) separately.Outcomes:There were 688 infants received screening. Among them,364 (52.92 %) were boys, and 324 (47.09%) were girls; birth weight ranged from 870～2100 grams, with an average of (1605.64±296.32) grams; gestational age ranged from 26.5～34.8 weeks, with an average of (32.36±2.08) weeks.521 (75.73%) cases were single pregnancy,159 (23.11%) cases were twins,5 (0.73%) cases were triplets, and 3 (0.44%)cases were quadruplets. Normal fundus was detected in 610 (88.66%) of 688 infants and ROP was detected in 78 (11.34%) of 688 infants. Among 78 cases,49 (7.22%) cases were at stage 1,25 (3.63%) cases were at stageⅡ,2 (0.29%) cases were at stagesⅢandⅣseparately. Among 78 cases, 28 cases (4.07%of 688 cases and 35.9% of 78 cases) with threshold diseases and pre-threshold type 1 received photocoagulation; 7 cases (1.02% of 688 cases and 8.97% of 78 cases) abandoned theory or lost of contact in follow-up; and other 43 cases (6.25% of 688 cases and 55.13% of 78 cases) were found regression of ROP in follow-up. All threshold and pre-threshold disease appeared 4-8 weeks after birth, with a corrected gestational age of (37.1±1.8) weeks. In the Multivariable Logistic Regression analysis, placental abruption and hypoxic-ischemic encephalopathy were statistic significant and were higher risks of ROP. In our research, there would be 20, 15 and 2 cases missed diagnosis if using American, English and European standard separately.Conclusions:Low birth weigh, low gestational age, long time of oxygen therapy, hypoxic-ischemic encephalopathy and placental abruption were higher risks of ROP. Standards recommended for ROP screening in NICU were infants with birth weight less than 1500 grams or gestational age less than 32 weeks. Age after birth/corrected gestational age was considered as a double standard for the first screening time, and the early one of them was selected.