Abstract: Objective To observ the normal intraocular pressure (IOP) of infants under 1 year old and to analyze the effect of retinal examination with wide field digital fundus imaging system (RetCam3) on their IOP. Design Prospective case series. Participants 285 cases (570 eyes) of ≤1 year old infants born at 24~40 weeks of pregnancy, wherein 176 were males, and 102 adult cases (204 eyes) with normal IOP, in Guangdong Women and Children Hospital between 2019 to 2020. Methods IOPs before and after RetCam3 retinal examinations in infacts as well as adults were measured by the ICare hand-held rebound tonometer. The differences of IOP between before and after RetCam3 retinal examinations and between infacts and adults were compared. Main Outcome Measures IOPs. Results The mean IOP of both eyes of infants was (13.04±3.04) mmHg, there was no significant difference between left and right IOP (t=-1.68，P=0.10). The both eyes mean IOP of adults was (16.82±2.36) mmHg. The IOP of infants was lower than that of adults (t=-18.14，P＜0.01). There was no statistical difference of IOP between different genders for infants (t=0.20，P=0.85). The IOP after RetCam3 examination was (13.93±3.20) mmHg, which was higher than that before examination (12.88±3.12 mmHg) (t=5.09，P＜0.01). The difference of IOP before and after fundus examination was more higher in <32 weeks group (1.64±3.76 mmHg) than ≥32 weeks group (0.75±3.22 mmHg) (t=2.12，P=0.04).  Conclusion The mean IOP of infants ≤1 year old is lower than adults. RetCam3 retinal examinationcan cause mild IOP increase in infants, and the effect is more obvious in the infants with smaller gestational age. (Ophthalmol CHN, 2022, 31: 345-348)

Key words: infants, intraocular pressure, RetCam