Clinical Investigation Of The Ocular Optical Components In High Myopia

PURPOSE:To investigate the refractive factors of axial length,corneal refractive power and the ratio of axial length:corneal radius (AL/R) in high myopia and emmetropiaMETHODS:Seventy-three highly myopic patients (146 eyes) and 164 emmetropes(328 eyes)were recruited.Corneal refractive powers and the axial length of globe were measured respectively using corneal topography(Germany Carl Zeiss Altas 955) and IOL-Master(Germany Carl Zeiss IOL Master Advanced Technology V.5.02). SPSS software package 16.0 were applied to perform the data analysis.RESULTS:There were statistically significant difference for the axial length and AL/R between highly myopic and emmetropic groups(P<0.0001);whereas corneal refractive powers showed no significant difference between two groups(P> 0.05). There were positive correlation between the axial length and corneal radius in emmetropic(r=0.513,P<0.0001),but no such correlation was observed in high myopia (r=0.037, P>0.05) CONCLUSIONS:â‘ The major change of ocular refractive components in high myopia was the elongation of axis. There was a higher AL/R ratio in high myopia than that in emmetropia.â‘¡The ocular axial length was positively correlated with corneal radius in emmetropia, but was not correlated with corneal radius in high myopia.â‘¢Further investigation is desired to understand the prediction role of AL/R in myopia development and emmetropization for human eye.