Figure 1. Relationship between the severity of diabetic retinopathy (DR) and the aqueous interleukin-1β level. The results by measuring cytokines in the aqueous humor samples shows that the interleukin-1β (IL-1β) level in aqueous humor increased with increasing severity of DR, and this correlation was significant (r=0.298, p<0.001). Table 3 shows the sampling sizes for each group according to the ETDRS retinopathy severity scale.