ABSTRACT
Objective:To explore the pupil size distribution of the Chinese myopic population under different mesopic conditions, and to analyze the possible influencing factors.Methods:A cross-sectional study was conducted.Two hundred and fourteen myopic patients (428 eyes) who underwent refractive surgery in Tianjin Eye Hospital from December 2018 to April 2019 were randomly selected.The patients were 17 to 45 years old, with an average age of (22.62±4.88) years old.The patients were divided into astigmatism <-1.5 D group (372 eyes) and astigmatism ≥-1.5 D group (56 eyes) according to their astigmatism measurements.The low mesopic pupil size (LMPS) (0.2 lx) was measured with the infrared Colvard pupillometer, and the high mesopic pupil size (HMPS) (6-12 lx) was obtained through the anterior Pentacam segment analyzer.The pupil size was compared between both eyes, different sexes and different astigmatism measurements.The relationship between pupil size and possible influencing factors, such as age, sex, spherical equivalent, spherical diopter, cylinder diopter, axis, mean keratometry(Km), and central cornea thickness was analyzed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Eye Hospital (No.201912). Written informed consent was obtained from each subject or their guardians.Results:The pupil sizes measured by the Colvard pupillometer and Pentacam were (6.806±0.776)mm and (3.312±0.540)mm, respectively.The pupil size of male subjects was (6.692±0.754)mm, which was larger than (6.668±0.792)mm of females, showing a statistically significant difference ( t=2.935, P=0.004). Under the high mesopic condition, the pupil size of astigmatism ≥-1.5 D group was lower than that of astigmatism <-1.5 D group, with a statistically significant difference ( t=2.611, P=0.009). Under the low mesopic condition, pupil size was negatively correlated with age and Km ( r=-0.213, -0.210; both at P<0.001). Under the high mesopic condition, pupil size was weakly positively correlated with cylinder power ( r=0.124, P=0.010) and was weakly negatively correlated with Km ( r=-0.142, P=0.003). The multiple linear regression analysis revealed that the LMPS=0.659×HMPS-0.019×age-0.084×Km+ 8.662.About 28% of pupil size under low mesopic conditions could be predicted by Pentacam.LMPS of ≤7 mm could be better predicted when the results were below 3.6 mm. Conclusions:Age and corneal curvature are influencing factors of mesopic pupil size.Older people with steep curvature have a smaller pupil.At high mesopic conditions, astigmatism affects pupil size.Pentacam measurements can predict LMPS to some degree but are not a substitute for dark-adapted pupil diameter.
ABSTRACT
Wavefront aberration is an evaluation index of objective visual quality.In recent years, the relationship between the wavefront aberration compensation in human eyes and the visual quality has been paid more and more attention.There is a mutual compensation relationship between various aberration terms, between corneal aberration and intraocular aberration, and between the anterior and posterior corneal surfaces, and the visual nervous system compensates human eye aberrations.The characteristics of aberration compensation change with age, and are different in analysis of different regions.Vision correction methods, such as refractive surgery and contact lenses, will change the aberration compensation relationship in human eyes, and the changes caused may have an impact on visual quality.It is important to understand the relationship between the aberration compensation characteristics in human eyes and the visual quality.Therefore, not only the existing aberrations should be taken into consideration, but also the compensation characteristics of human eye aberrations must be elucidated to make personalized correction for the aberrations and improve the visual quality after correction.The research progress and significance on the relationship between human eye aberration compensation characteristics and visual quality were reviewed in this article.