Effect of misalignment of analytical centers on higher-order aberration

• Published in: JAPANESE ORTHOPTIC JOURNAL Vol. 35; pp. 69 - 76
• Main Authors: Kuraoka, Sachiko, Suto, Chikako, Shimamura, Emiko, Sato, Chiaki, Takahashi, Midori
• Format: Journal Article
• Language: English
• Published: JAPANESE ASSOCIATION OF CERTIFIED ORTHOPTISTS 2006
• Subjects: analysis at the center of corneal reflex; analysis at the center of pupil; Hartmann-Shack wavefront sensor; higher-order aberration; misalignment of the analytical centers
• DOI: 10.4263/jorthoptic.35.69
• ISSN: 0387-5172

[Purpose] Effect of misalignment of the analytical centers on higher-order aberration was examined. [Cases and Methods] The subjects were divided into a group of phakia; 23 eyes in 23 subjects with no disorder other than ametropia, and an IOL group; 23 eyes in 23 subjects implanted with intraocular lens were evaluated with using a Hartmann-Shack wavefront sensor (KR-9000PW™; Topcon). Analysis was performed at the center of pupil and the center of corneal reflex in order to obtain the corneal aberration and the total ocular aberration (comalike aberration, spherical-like aberration and total higher-order aberration) at pupil diameter of 4mm. (1) Misalignment of the analytical centers (distance between the center of pupil and the center of corneal reflex) (2) aberration amount in analysis at the center of pupil and the center of corneal reflex (3) change quantity of aberration (absolute value of the difference between the center of pupil and the center of corneal reflex) (4) correlation between the misalignment of the analytical centers and the change quantity of aberration were examined. [Results] (1) Misalignment of the analytical centers did not present significant difference between the two groups. (2) Corneal aberration presented significant difference in both groups for comalike aberration and total higher-order aberration, while total ocular aberration presented significant difference in the IOL group for all aberrations. (3) In change quantity of aberration, corneal aberration did not present significant difference between the two groups, while total ocular aberration were significantly larger in the IOL group than in the group of phakia for comalike aberration and total higher-order aberration. (4) Corneal aberration increased in the change quantity of aberration as the misalignment in the centers of analysis intensified, in both groups. Total ocular aberration did not indicate relation with misalignment of the analytical centers in the group of phakia, while positive correlation with the misalignment of the analytical centers was observed in IOL group. [Conclusion] Misalignment of the analytical centers has greater influence on eyes with IOL than on the phakic eyes. Lack of mydriasis or concentrical mydriasis may alter the center of pupil, thus resulting in misalignment of the analytical centers; the measurements should be taken with the pupil uniformly open.