Congenital cataract is the main cause of form deprivation amblyopia in children. Current studies confirm that form deprivation amblyopia affects the retinal nerve fiber layer. However, there are different opinions about the effect of amblyopia on the optic nerve fiber thickness around the optic disc at home and abroad. Investigators have performed "cataract extraction with IOL implantation" on children with bilateral and unilateral congenital cataract. Investigators used OCT biometry to measure children's the retinal nerve fiber layer (RNFLT) and macular thickness (CMT) before and after surgery. Investigators dynamically observed changes in RNFL and CMT to explore the retinal mechanism of form deprivation amblyopia and help guide the clinical correct understanding of postoperative follow-up time.

This prospective study reviewed children with CC who were undergoing cataract extraction with IOL implantation at the Eye Hospital of Wenzhou Medical University, Hangzhou, China. bilateral and unilateral CC children were placed in Study group, while age-matched normal children were included as controls. Children who were uncooperative to complete the preoperative and postoperative examinations were excluded.

All eyes were divided into 4 groups. Group 1: form deprivation amblyopia of unilateral CC, Group 2: unaffected eyes of unilateral CC, Group 3: form deprivation amblyopia of bilateral CC, Group 4: normal eyes of normal children. The preoperative and postoperative data including sex, age at surgery, 7 position of RNFLT and CMT were collected.

All surgeries were performed by the same surgeon (Y.E.Z.) under general anesthesia. Investigators used OCT biometry to measure participants' the retinal nerve fiber layer (RNFLT) and macular thickness (CMT) before surgery and 1 week, 1 month, 3 months, and 6 months and 1 year after surgery, and compared with age-matched normal children.

Inclusion Criteria:

• congenital cataract

Exclusion Criteria:

• incooperative to complete the preoperative and postoperative examinations