Congenital cataracts (CC) are the leading cause of childhood visual disabilities and treatable childhood blindness worldwide1. CC patients have a wide range of presentations of lens opacities and are generally categorized into several groups based on the etiologies, anatomical positions, or shapes of lens opacities. Cataractous eyes of CC patients are also frequently complicated with other anterior segment abnormalities due to their close anatomical relationships and similar developmental origins. Lens opacities in different positions may be related to specific anterior segment abnormalities; for example, anterior polar cataracts are associated with greater corneal astigmatism (CA). However, no studies have systematically related the position of lens opacities to specific anterior segment abnormities, mainly due to the small number of CC patients, a lack of proper equipment, and a lack of awareness of these important relationships.

Congenital cataracts (CC) are the leading cause of childhood visual disabilities and treatable childhood blindness worldwide1. CC patients have a wide range of presentations of lens opacities and are generally categorized into several groups based on the etiologies, anatomical positions, or shapes of lens opacities. Cataractous eyes of CC patients are also frequently complicated with other anterior segment abnormalities due to their close anatomical relationships and similar developmental origins. Lens opacities in different positions may be related to specific anterior segment abnormalities; for example, anterior polar cataracts are associated with greater corneal astigmatism (CA). However, no studies have systematically related the position of lens opacities to specific anterior segment abnormities, mainly due to the small number of CC patients, a lack of proper equipment, and a lack of awareness of these important relationships.

Using the largest CC database in the Zhongshan Ophthalmic Center (ZOC), the current study compared the anterior segment characteristics of CC patients with lens opacities in different positions and further proposed a modified CC category system based on the specific relationships between the position of lens opacities and anterior segment characteristics. Knowledge of these relationships is beneficial for further understanding of CC occurrence and development and has clinical significance for CC diagnosis and treatment.

Inclusion Criteria:

• Diagnosis of congenital cataract
• less than 18 years old

Exclusion Criteria:

• With other ocular abnormalities including severe corneal diseases, lens luxation, glaucoma, retinal diseases, nystagmus, nanophthalmos, and strabismus.

This was a prospective study and was included in our series of ongoing studies at the Childhood Cataract Program of the Chinese Ministry of Health (CCPMOH), a national project for congenital cataract (CC) treatment and research. CC patients less than 18 years old and seeking treatment at the ZOC, one of the best eye care facilities in China, from February 2011 to December 2015 were candidates for this study. All included participants were diagnosed with CC before surgery and lacked other ocular abnormalities, such as severe corneal diseases, lens luxation, glaucoma, retinal diseases, nystagmus, nanophthalmos, and strabismus. A total of 428 CC patients were included.