Objective To determine the incidence of and risk fact ors for retino pathy of prematurity (ROP) among preterm infants in Beijing after implementation of the ROP guidelines. Methods The preterm infants with birth weight le; 2000 g or gestational age le; 3 4 weeks who were admitted to the neonatal intensive care units in 6 hospitals in Beijing from Jan. 1, 2005 to Dec. 31, 2005 were screened. Ophthalmologic examin ations started 3-4 weeks after birth and ROP was classified by the revised Inte r national Classification. Maternal and perinatal risk factors of occurrence of R OP were analyzed. Results In the 639 infants who had been scre ened in the 6 ho spitals, ROP was detected in 69 (10.8%), in whom 23 infants (39 eyes) (3.6%) had type 1 ROP and underwent photocoagulation. The lower the birth weight and small er the gestational age was, the higher the incidence of ROP was. Logistic regres sion analysis indicated that low birth weight, apnea gt;20 seconds, anemia, hypoxic-ischemic encephalopathy and placenta abruption were the high risk factor of R O P.Conclusion In Beijing the incidence of ROP is 10.8% after i mplementation of the ROP guidelines. Low birth weight, apnea gt;20 seconds, anemia, hypoxicischem ic encephalopathy and placenta abruption were the high risk factor of ROP.
Objective To investigate the degree of retinal development in preterm infants.MethodsFlash electroretinography (ERG) was performed on 25 healthy preterm infants and 25 full-term ones, and the response of rod cells and cone cells and maximal mixed responses were recorded. The delitescence and amplitudes of a-and b-waves and the ratio of amplitudes of b-/a-wave of maximal responses were analyzed. ResultsCompared with the full-term infants, The delitescence of responses of rod cells in preterm infants was statistically longer（t=11.007，P=0.000）but without any significant changes of amplitudes （t=1.836，P=0.069）; statistically longer delitescence (t=2.44, P=0.010; t=10.800, P=0.000) and lower amplitude (t=5804，P=0.000; t=5.809,P=0.000) of a-and b-wave of maximal response were found in preterm infants group. In the response of cone cells, there were significant differences of the delitescence （t=4.444，P=0.000）and amplitude （t=3.819，P=0.000）of a-wave and delitescence of b-wave（t=2.850，P=0.005） between the two groups, and no statistical difference of amplitude of b-wave （t=0.486，P=0.628） between the two groups. The ratio of amplitudes of b-/a-wave of the maximal mixed response was not significantly different between the two groups （t=1.142，P=0.256）.ConclusionsThe development of retinal function is slower in preterm infants than that in full-term ones.(Chin J Ocul Fundus Dis, 2005,21:285-287)
Objective To observe the characteristics of morphological development of premature retina at 33-46 weeks of gestational corrected age (GCA). Methods A total of 268 premature infants were divided into 7 groups according to the GCA (33-34，35-36，37-38，39-40，41-42，43-44 and 45-46 weeks). The ocular fundus of those infants were recorded and analyzed by an indirect ophthalmoscopelinked imaging system. Results As GCA increases, noticeable macular morphological changes occurred and recorded in 96% of infant at 45-46 weeks of GCA. Retinas were gradually vascularized at 41-42 weeks (nasal retina) or 43-44 weeks (area Ⅲ,temporal retina), and pigmented in 84% of infant at 45-46 weeks of GCA. Conclusion Macular morphological patterns, retinal blood vessels and pigments continue to develop in postnatal premature infants.
Objective To investigate the incidence of retinopathy of prematuri ty (ROP) in the area of Shanghai, and to provide the preliminary data for the ev aluation of present criteria for ROP screening. Methods Record s of 289 prematur e infants who had undergone ROP screening from the four NICU in Shanghai between February 2004 and January 2005 were analyzed. Screening criteria included prete rm infants or low birth weight (LBW) infants with BW of 2000g or less. The first examination starts at 4 to 6 weeks chronologic age or 32 weeks post conceptual age. Results In the 289 screened infants, 19 had developed acu te ROP. There we re 3 threshold ROP, 7 prethreshold ROP and 9 developed ROP less than prethreshol d. The incidence of ROP was 6.6%. According to the British recommended guideline s（BWle;1500 g or GAle;31 weeks）, only 119 out of 289 needed screening and one ca se of stage 1 ROP was missed; the incidence of ROP was 15.1% (18/119). When lowered sc reening criteria to the American guidelines（BWle;1500g or GAle;28 weeks）, t here were only 83 infants needed screening, and we missed 2 stage 1 and 1 prethreshold ROP and the incidence of ROP was 19.3% (16/83). Conclusions The i ncidence of ROP i s 6.6% according to our study. It is lower than other reports and it has somethi ng to do with our present screening guideline. Further epidemiological data are needed to modify the guideline accordingly.