METHODS: A total of 2 527 infants were screened for ROP in Suzhou from January 2011 to December 2015 using RetCamII. First examination was performed from 4-6wk after birth. Of all the 2 527 infants, the birth weight was 640-4 200g with an average of 1694.99±370.875g. The gestational age were 24.5-41.1wk with an average of 32.397±2.2171wk. The ocular findings were recorded according to the International Classification of ROP and The Early Treatment for ROP. Only the more aggressive eye of bilateral asymmetrical cases was counted for statistical purpose. And the cases required surgeries(pre-threshold ROP type Ⅰ and threshold ROP)were defined as severe cases.

RESULTS: Of all the 2 527 infants, 408 infants were screened with ROP, in which 30 were severe ROP, the incidence of ROP and severe ROP was 16.15%and 1.19%. The incidence of ROP from 2011 to 2015 were 10.14%, 14.91%, 14.26%, 19.64%, 20.15% respectively, turned out a gradual upward trend(χ²=24.625, P<0.01). The incidence of severe ROP were 1.18%, 0.94%, 0.63%, 0.90%, 2.22%, no significant differences between the groups(P>0.05). The incidence of ROP in the four seasons were 17.62%, 15.20%, 16.12%, 15.82% respectively and no significant differences between the groups(χ²=1.397, P=0.706).

CONCLUSION: The incidence of ROP in Suzhou increased from 2011 to 2015, which was related to the decline of the gestational age and birth weight. The distribution of ROP was not seasonal.