Abstract:

BACKGROUND: High order aberrations (HOA) are a key factor that influences vision quality following low order aberrations rectification. As a rectification of ametropia, corneal contact lens corrects low order aberrations, but the changes in HOA require exploration.
OBJECTIVE: To evaluate the influence of hydrogel soft contact lenses (SCL) for correction of myopia on HOA. 
METHODS: Monochromatic aberrations of the whole eye were measured with a COAS Shack-Hartmann wavefront analyzer before and after wearing SCL for myopia correction with a natural pupil. The fitted Zernike coefficients were calculated for each eye including 47 myopic eyes with fixed optical zones of 6.0 mm. Each order aberrations and total high order aberrations from 3rd to 6th before and after correcting the lower order aberrations in myopia were compared, and the relationship of changes in refraction, C20 and C40 was analyzed respectively.
RESULTS AND CONCLUSION: SCL yielded larger high order aberrations (t =2.125, P=0.039) including more coma (t =3.843, P=0.000) and less spherical aberration (t =–8.319, P=0.000). The change in spherical aberration was highly positively correlated with the changes in negative power of the contact lens (r=0.536, P=0.000). Correcting myopia defocus affects HOA. SCL for myopia induced a significant increase in total HOA. The spherical aberration of myopia subject changes statistically with sphere trial SCL.