Abstract
Purpose: To evaluate the association among age, gender, central corneal thickness (CCT), anterior chamber depth (ACD) and higher-order aberrations (HOAs) of cornea in Chinese people with emmetropia by Pentacam. Methods: Prospective, a non-randomized population-based study. All subjects came spontaneously for consultation and were subdivided into six age-groups. One thousand two hundred and six candidates (605 male, 601 female) were tested and underwent Anterior segment examination by Pentacam. These parameters were measured: 1) root mean square-HOA (RMS-HOA) from anterior and posterior cornea, 2) RMS of coma, secondary astigmatism and spherical aberration (SA) from anterior and posterior cornea, 3) CCT and ACD. Results: For analysis of variance (ANOVA) between genders, there were statistical differences on: 1) anterior corneal HOAs of x-coma, y-coma and SA (F=5.643, P=0.018; F= 16.971, P=0.000; F=23.443, P=0.000); 2) total corneal HOAs of y-coma and SA (F=12.906, P=0.000; F=111.590, P=0.000). There was significant different between y-second astigmatism of anterior corneal surface and age (r2 =0.023, p<0.000), that of posterior corneal surface and age (r2 =0.021, p=0.001), between RMS-HOAs of anterior corneal surface and age (r2 =0.259, p<0.000), that of posterior corneal surface and age (r2 =0.055, p=0.001), that of total corneal surface and age (r2 =0.359, p<0.000). Conclusion: a) For the ethnic, there was a significant difference on magnitude of corneal HOAs between Chinese people and the other people. b) Pentacam can provide a more precise data of posterior cornea HOAs which seldom reported before.
Highlights
Aberration as an element of vision quality assessment is defined as the difference between a real image and an ideal image and if it occurs, the quality of vision becomes poorer
Compared with posterior and total corneal surface, a curve fitting relationship was found in anterior corneal surface for x-coma; linear regression showed statistic differences between x-coma of posterior corneal surface (y=0.250-0.329x, r2 =0.108, p
As is known, posterior corneal surface plays an important role in cornea and may be the first abnormal in some corneal diseases
Summary
Aberration as an element of vision quality assessment is defined as the difference between a real image and an ideal image and if it occurs, the quality of vision becomes poorer. We are usually interested in the total wavefront aberration of the eye (ocular wavefront aberration), it is sometimes valuable to know the contribution that the cornea (or more strictly the anterior air–tear film interface; posterior corneal surface and total cornea surface) makes to the total aberration This can be estimated from the surface height data provided by corneal topographers. Pentacam Instruments are beginning to become available which combine an aberrometer with a corneal topographer and can yield the wavefront aberrations of both the whole cornea alone and anterior or posterior corneal aberration, respectively [1] (Figure 1) Another fact is that corneal and ocular HOAs have been studied for many years; it is only relatively recently that the aberrational characteristics of large populations of normal subjects have been analyzed in Zernike terms [2,3,4].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Clinical & Experimental Ophthalmology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
