[Effects of three madriatics on the human ocular aberrations]

To evaluate the effects of three common madriatics-phenylephrine, tropicamide and Mydrin-P on aberrations in human eye.

General aberrations, lower- and higher-order aberrations (HOA) were measured at the pupil diameter 4.0 mm and 7.0 mm with Allegretto Wave Analyzer on 37 eyes of 19 young volunteers whose spherical equivalence (SE) ranged from -0.25 D to -6.00 D. Four measured conditions were used for each subject. (1) Topical installation of 3 drops 5.0% phenylephrine hydrochloride. (2) Topical installation of 3 drops 0.5% tropicamide. (3) Topical installation of 3 drops Mydrin-P. (4) Topical installation of 3 drops 0.3% Tarivid, prior to aberometry measurements. The differences were analyzed on the values of the root-mean-square (RMS) of general (RMSg) and higher-order aberrations (RMSh), coefficient of defocus, astigmatism, the third aberrations, primary spherical aberration and the dominating type of HOA among three madriatics or between the madriatics and Tarivid solution respectively.

There was no significant difference among the three madriatics in the average value of RMSg, RMSh, C3-C9 and C12 (P > 0.05). However, small but statistically significant difference was found in the disparity between any madriatic and Tarivid at the condition of 4.0 mm diameter of pupil. The disparity of 5% phenylephrine over RMSg and C4 was the smallest, and showed significant difference (P < 0.05). The third order aberration was more frequent dominating type of HOA over a 4.0 mm and 7.0 mm pupil for 4 eye drops, and C7 was the most frequent one among all the volunteers; there were 28 eyes (75.7%), 20 eyes (54.1%) which dominating type of HOA changed.

All the three madriatics can be used to measure the higher-order aberrations, spherical aberration and coma in the young myopic persons. However, phenylephrine measurement may be the choice for lower-order aberrations.