The Study Of Retinal Function Development Between Normal Premature Infants And Infants With Laser Treatment Due To Retinopathy Of Prematurity

Objective:To investigate the frequency of retinal development in Preterm newboms who are 6 to 18 monthes;and To assess the functional and structural outcomes of premature babies who received diode laser photocoagulation for threshold retinopathy of prematurity.compare the electroretinograms between Preterm infants and premature babies who received diode laser photocoagulation for threshold retinopathy of prematurity.MeanWhile to determine electroretinographie Parameters according to the standard Protoeol from the International Society for clinical ElectroPhysiology of Vision (ISCEV) in laser treated eyes.Methods:1.100 preterm infants with no sign of ROP and all with normal fundus,were recruited and divided in five groups.20 preterm babies (40 eyes)with gestation age=32.4±1.32w and and adjusted age at test=6m: 20 preterm babies (40eyes) with gestation age=31.77±2.13w and and adjusted age at test=9m: 20 preterm babies (40eyes) with gestation age=32.48±3.18w and and adjusted age at test=12m: 20 preterm babies (40eyes) with gestation age=32.84±2.3w and and adjusted age at test=15m: 20 preterm babies (40eyes) with gestation age=31.96±3.11w and and adjusted age at test=18m.2. 30 patients (60 eyes) were treated with laser and 30 preterm infants (60 eyes) who have no ROP recalled for assessment at a mean follow up of 1 year. All children underwent Flash electroretinogram .including the response of rod cells and cone cells and maximal mixed responses. Oscillatory Potentials and 30Hz flicker responses and the ratio of amplitudes of b/a wave of maximal responses were analyzed.Results:1. The F-ERG waveform of 6 months, 9 months, 12 months, 15 months and 18 months preterm infants show that: the infant's age is elder, The amplitudes of the rod-ERG is significant higher , The amplitudes of the cone-ERG,the max-ERG,Ops and 30HZflicker are significant higher.Max-ERG is no correlation with the infant's age.the infant's age is elder,the latent period of b-wave of the F-ERG is more shorter.2.Compared with the healthy preterm infants, statistically longer latent period (P=0.006) and lower amplitude (P=0.019) of rod cells response were found in laser treated eyes. The amplitudes of a-and b-wave of maximal response in laser treated eyes were statistically lower(P=0.004; P=0.000) but without any significant changes of latent period (P=0.104; P=0.643). The ratio of amplitudes of b-/a-wave of the maximal mixed response was not significantly different between the two groups (P=0.163). In the response of cone cells, there were no significant differences of the latent period (P=0.224) of a-wave and amplitude (P=0.526) of a-wave and b-wave (P=0.056) between the two groups. The latent period of b-wave (P=0.023) of cone cells was longer in laser treated eyes. Lower amplitude (P=0.015) of oscillatory potentials response was found in laser treated eyes.Conclusions:1. The development of all kinds of retina cells can be demonstrated by F-ERG records. Through these records, we found the amplitudes of F-ERG was positively correlated with the infant's age and the latent period of F-ERG was negatively correlated with the infant's age. The function of retina developed better when premature infants got elder.2. The functional outcomes of the cone photoreceptors of premature babies who received diode laser photocoagulation for threshold retinopathy of prematurity is close to the preterm infants without ROP. but the development of the laser treated rod photoreceptors is weaker than the normal eyes.