Abstract:AIM:To study the distribution of Q-values on corneal anterior surface and analyze its correlation with corneal spherical aberration (C12) and total spherical aberration (C12) respectively. ·METHODS:One hundred myopia eyes were evaluated with TOPOLYSER,Humphrey and WASCA,and the eccentricities (e-value) of corneal surface (20°,25° and 30°),CTS data and total spherical aberration (diameter=6.0mm) were recorded respectively. The e-values were analyzed using formula (Q=-e2) to obtain Q-value. CTS data were analyzed using Matlab software to obtain the spherical aberration of cornea (diameter=6.0mm). ·RESULTS:The Q-values of corneal anterior surface (20°,25° and 30°) were-0.144(M),-0.213±0.110 and-0.277±0.108,respectively. The corneal and total spherical aberrations (diameter=6.0mm) were 0.25712±0.06914μm and 0.06630±0.10823μm,respectively. Q-value of 25° had high correlation (r=0.673,P=0.000) with corneal spherical aberration,but low correlation (r=0.241,P=0.016) with total spherical aberration. ·CONCLUSION:Firstly,corneal surface is much flatter from center to periphery and the absolute values of Q become much larger. Secondly,the Q-value of 25° has high correlation with corneal spherical aberration but low correlation with total spherical aberration.