Abstract
Purpose: :
To study the effects of phenylephrine 5% topical administration on accommodative response and optical aberrations variation in young healthy subjects.
Methods: :
The research followed the tenets of the Declaration of Helsinki . 28 eyes from 14 volunteers with spherical equivalent defocus error between -2D and +1D, no eye disease history and between 20 to 25 years of age, underwent wavefront measurements with an Imagine Eyes® IRX3 Shack-Hartmann wavefront aberrometer which included a movable accommodative target. Wavefront data was acquired while applying 6 different increasing accommodative stimuli, from 0 D to 5 D by steps of 1 D, before and after pupil dilation with Phenylephrine 5%.
Results: :
The dilation using Phenylephrine 5% was found to larger lag errors in the accommodative response of about half of the subjects. The total RMS amount of aberrations above defocus remained stable during accommodation with and without dilation. Spherical aberration was positive in average in the non accommodated eye and changed toward negative values with increasing accommodation (p<0.05). Cylinder axis came closer to 90° as accommodation increased (p<0.05). Although vertical coma did not significantly vary with accommodation, horizontal coma increased significantly with accommodation (p<0.05). These changes in aberrations with increasing accommodation were similar on average in both pupil conditions.
Conclusions: :
Phenylephrine 5% modifies the accommodative focus response of a significant proportion of young adult eyes. Wavefront aberrations above defocus undergo similar variations in both natural and dilated pupil conditions. However the total RMS error of aberrations above defocus remains relatively constant when the eye accommodates.
Keywords: accomodation • aberrations • optical properties