Abstract: Objective To investigate the biometry data of eyes with congenital cataract (CC) in North China. Design Retrospective case series. Participants 117 CC patients under 18 years old in Beijing Tongren Hospital from 2010 to 2018. Methods The medical records of CC patients were reviewed. All patients underwent A-scan, keratometry examination or IOL-Master 500 examination. CC patients were grouped according to their age (1~24 months, 25~72 months, and 73~216 months), gender (male or female) and whether both eyes were affected (monocular or binocular), and the ocular biometrics between different groups were compared. For patients with monocular CC, the differences between cataract eyes and contralateral eyes were also analyzed.  Main Outcome Measures axial length, keratometry and corneal astigmatism. Results The average axial length, keratometry and corneal astigmatism of 117 CC patients were 21.92±1.76 mm, 43.78±1.81 D, and 2.03±1.10 D respectively. The axial length of CC patients in 1~24 months group, 25~72 months group and 73~216 months group were 20.59±1.31 mm, 22.00±1.70 mm and 22.60±1.65 mm respectively (F=11.99, P<0.001). There was no significant difference in keratometry and corneal astigmatism among different age groups (F=0.330, P=0.720 and F=0.625, P=0.537). There was no significant difference in axial length and keratometry between different gender groups (t=-1.862, P=0.065 and t=1.709, P=0.090). There was no difference in axial length and keratometry between monocular and binocular CC patients (t=1.272, P=0.206 and t=-0.145, P=0.885). There was no significant difference in axial length and keratometry between cataract eyes and contralateral eyes in monocular CC patients (t=-0.624, P=0.536 and t=-0.201, P=0.842), but the corneal astigmatism of cataract eyes was larger (2.05±1.00 D vs 1.38±0.83 D, P<0.001). Conclusion CC may defer the physiological decrease of corneal astigmatism. The axial length of CC patients increased rapidly before 2 years old, and slowly after 2 years old, which provided a reference for the selection of appropriate time for intraocular lens implantation in CC patients. (Ophthalmol CHN, 2021, 30: 36-41)

Key words: congenital cataract, axial length, keratometry, corneal astigmatism