Preliminary Research On Retinal Function Of Preterm Infants With FERG

ObjectiveTo investigate the degree of retinal development in preterm newborns and compare the electroretinograms between preterm and full-term newborns.Meanwhile to determine electroretinographic parameters according to the standard protocol from the International Society for Clinical Electrophysiology of Vision (ISCEV) in healthy preterm infants with normal fundus.Methods20 full-term infants and 30 preterm infants with no sign of ROP and 10 adults,all with normal fundus,were recruited and divided in six groups:full-term 40-week group,ten newborns with gestation age=40w and adjusted age at test＜1 week;full-term 44-week group,ten newborns with gestation age=40w and adjusted age at test=1 month;preterm 35-week group,ten newborns with gestation age=35w and adjusted age at test＜1 week;preterm 37-week group,ten newborns with gestation age=40w and adjusted age at test=2-3 weeks;preterm 40-week group,ten newborns with gestation age=40w and adjusted age at test=1 month and adult group.Full-field ERGs were obtained with contact lens electrode from the anesthetized cornea in one eye.The standard ISCEV protocol was used and the following responses were recorded:rod,maximal,oscillatory potentials,cone and 30Hz flicker.Then compare the FERGs of full-term 40w group,full-term 44w and adult group;preterm 35w group with full-term 40w group;preterm 40w group with full-term 40w group;preterm 35w group,37w group and 40w group.Results1.To compare full-term 40w group,full-term 44w and adult group,we find similar FERG can be recorded in full-term newborns to adult,only with lower amplitudes and larger implicit time. 2.To compare preterm 35w group with full-term 40w group,we find statistically smaller amplitudes in preterm 35w group for rod,maximal,cone and 30Hz filcker and no statistical differences in implicit time between the two groups except b wave in rod response.3.To compare preterm 40w group with full-term 40w group,we find smaller implict time in preterm 40w group for a wave in max response and a wave and b wave in cone response and no statistical differences in amplitudes between the two groups.4.To compare b wave in rod and cone responses between preterm 35w group, 37w group and 40w group,we find there is similarity in implicit time between rod and cone response while the amplitude of rod response rises rapidly in early stage,that of cone response rising rapidly in late stage.Conclusions1.The retina has developed in a certain degree at birth,but there exist obvious differences compared to adults.2.The development of retinal function is slower in preterm infants than that in full-term ones.3.The retinal development of preterm infants with adjusted age=40w has reach the degree of that in full-term ones at birth.