屈光手术前个体眼高阶像差与中间视觉状态下瞳孔大小

目的:研究眼高阶像差的分布(HOAs)和mesopic瞳孔的大小在个体中筛选的屈光手术。 方法:我们采用Zywave像差分析仪（博士伦）分别对患有近视、近视散光和复性近视散光患者1240例2458眼和患有远视、远视散光和复性远视散光患者110例215眼的高阶像差和瞳孔大小进行检测。所有患者屈光不正均可矫正,无屈光手术史或潜在疾病。HOAs的均方根值、总球面像差、总斜射球面像差和中间视觉状态下瞳孔的大小进行了分析,眼高阶像差测量均在瞳孔≥6.0mm,且瞳孔大小的测量均为在中间视觉状态下进行。 结果:HOAs均方根值、总球面像差和总斜射球面像差在近视眼组与远视眼组分别为0.369±0.233μm、0.133±0.112μm、0.330±0.188μm;0.418±0.214μm、0.202±0.209μm、0.343±0201μm。与近视患者相比,远视患者的总HOAs和总球面像差更大(P均＜0.01)。年龄匹配分析显示在远视眼组只有总球面像差较高（P=0.05）。近视眼组的中间视觉状态下瞳孔大小较大（P≤0.05）。 结论:实验结果表明两组的HOAs的水平有显著差异,这对于将行屈光手术的伊朗人很重要。远视眼组的总球面像差显著高于近视眼组,中间视觉状态下瞳孔大小在近视眼组较大。     

Myopic versus hyperopic eyes: axial length, corneal shape and optical aberrations

This study investigated differences in geometrical properties and optical aberrations between a group of hyperopes and myopes (age-matched 30.3+/-5.2 and 30.5+/-3.8 years old, respectively, and with similar absolute refractive error 3.0+/-2.0 and -3.3+/-2.0, respectively). Axial length (AL) was measured by means of optical biometry, and corneal apical radius of curvature (CR) and asphericity (Q) were measured by fitting corneal topography data to biconic surfaces. Corneal aberrations were estimated from corneal topography by means of virtual ray tracing, and total aberrations were measured using a laser ray tracing technique. Internal aberrations were estimated by subtracting corneal from total aberrations. AL was significantly higher in myopes than in hyperopes and AL/CR was highly correlated with spherical equivalent. Hyperopic eyes tended to have higher (less negative) Q and higher total and corneal spherical aberration than myopic eyes. RMS for third-order aberrations was also significantly higher for the hyperopic eyes. Internal aberrations were not significantly different between the myopic and hyperopic groups, although internal spherical aberration showed a significant age-related shift toward less negative values in the hyperopic group. For these age and refraction ranges, our cross-sectional results do not support evidence of relationships between emmetropization and ocular aberrations. Our results may be indicative of presbyopic changes occurring earlier in hyperopes than in myopes.     

Characteristics of higher-order aberrations and anterior segment tomography in patients with pathologic myopia

Purpose

To investigate prospectively the characteristics in the higher-order aberrations and anterior segment tomography in patients with pathologic myopia.

Methods

One hundred and twelve consecutive highly myopic patients (mean age 43.4 ± 9.3 years, spherical equivalent of refractive error ≥8 D and an axial length ≥26.5 mm) were studied. Thirty-seven emmetropic individuals (mean age 37.0 ± 14.5 years, spherical equivalent of refractive error ≤ ±1 D) were analyzed as controls. The ocular and cornea higher-order aberrations were measured using a Hartmann–Shack wavefront sensor (KR-1W; Topcon Corporation, Tokyo, Japan). The crystalline lens rise, the angle-to-angle, and the white-to-white values were measured using anterior segment OCT (SS-1000; Tomey Corporation, Nagoya, Japan). The mean curvature of the anterior corneal surface, the thickness at the thinnest central corneal point, the location of the central corneal point, the corneal volume, the anterior chamber volume, and the anterior chamber depth were measured using the Pentacam HR (Oculus, Inc., Wetzlar, Germany).

Results

The ocular total higher-order aberration for 4-mm pupil, the ocular spherical aberrations, and internal spherical aberration for 6-mm pupil were significantly higher in highly myopic eyes than in the emmetropic controls. The crystalline lens rise was significantly smaller in highly myopic eyes than in the emmetropic controls. The anterior chamber depth and the anterior chamber volume were significantly larger in highly myopic eyes than in the emmetropic controls.

Conclusion

Highly myopic eyes had higher-order aberrations than emmetropic eyes because of the increasing internal aberrations.

     

Spectacle lens compensation in the pigmented guinea pig

When a young growing eye wears a negative or positive spectacle lens, the eye compensates for the imposed defocus by accelerating or slowing its elongation rate so that the eye becomes emmetropic with the lens in place. Such spectacle lens compensation has been shown in chicks, tree-shrews, marmosets and rhesus monkeys. We have developed a model of emmetropisation using the guinea pig in order to establish a rapid and easy mammalian model. Guinea pigs were raised with a +4D, +2D, 0D (plano), −2D or −4D lens worn in front of one eye for 10 days or a +4D on one eye and a 0D on the fellow eye for 5 days or no lens on either eye (littermate controls). Refractive error and ocular distances were measured at the end of these periods. The difference in refractive error between the eyes was linearly related to the lens-power worn. A significant compensatory response to a +4D lens occurred after only 5 days and near full compensation occurred after 10 days when the effective imposed refractive error was between 0D and 8D of hyperopia. Eyes wearing plano lenses were slightly more myopic than their fellow eyes (−1.7D) but showed no difference in ocular length. Relative to the plano group, plus and minus lenses induced relative hyperopic or myopic differences between the two eyes, inhibited or accelerated their ocular growth, and expanded or decreased the relative thickness of the choroid, respectively. In individual animals, the difference between the eyes in vitreous chamber depth and choroid thickness reached ±100 and ±40 μm, respectively, and was significantly correlated with the induced refractive differences. Although eyes responded differentially to plus and minus lenses, the plus lenses generally corrected the hyperopia present in these young animals. The effective refractive error induced by the lenses ranged between −2D of myopic defocus to +10D of hyperopic defocus with the lens in place, and compensation was highly linear between 0D and 8D of effective hyperopic defocus, beyond which the compensation was reduced. We conclude that in the guinea pig, ocular growth and refractive error are visually regulated in a bidirectional manner to plus and minus lenses, but that the eye responds in a graded manner to imposed effective hyperopic defocus.     

Binocular lens treatment in tree shrews: Effect of age and comparison of plus lens wear with recovery from minus lens-induced myopia

We examined normal emmetropization and the refractive responses to binocular plus or minus lenses in young (late infantile) and juvenile tree shrews. In addition, recovery from lens-induced myopia was compared with the response to a similar amount of myopia produced with plus lenses in age-matched juvenile animals. Normal emmetropization was examined with daily noncycloplegic autorefractor measures from 11 days after natural eye-opening (days of visual experience [VE]) when the eyes were in the infantile, rapid growth phase and their refractions were substantially hyperopic, to 35 days of VE when the eyes had entered the juvenile, slower growth phase and the refractions were near emmetropia. Starting at 11 days of VE, two groups of young tree shrews wore binocular +4 D lenses (n = 6) or −5 D lenses (n = 5). Starting at 24 days of VE, four groups of juvenile tree shrews (n = 5 each) wore binocular +3 D, +5 D, −3 D, or −5 D lenses. Non-cycloplegic measures of refractive state were made frequently while the animals wore the assigned lenses. The refractive response of the juvenile plus-lens wearing animals was compared with the refractive recovery of an age-matched group of animals (n = 5) that were myopic after wearing a −5 D lens from 11 to 24 days of VE. In normal tree shrews, refractions (corrected for the small eye artifact) declined rapidly from (mean ± SEM) 6.6 ± 0.6 D of hyperopia at 11 VE to 1.4 ± 0.2 D at 24 VE and 0.8 ± 0.4 D at 35 VE. Plus 4 D lens treatment applied at 11 days of VE initially corrected or over-corrected the young animals’ hyperopia and produced a compensatory response in most animals; the eyes became nearly emmetropic while wearing the +4 D lenses. In contrast, plus-lens treatment starting at 24 days of VE initially made the juvenile eyes myopic (over-correction) and, on average, was less effective. The response ranged from no change in refractive state (eye continued to experience myopia) to full compensation (emmetropic with the lens in place). Minus-lens wear in both the young and juvenile groups, which initially made eyes more hyperopic, consistently produced compensation to the minus lens so that eyes reached age-appropriate refractions while wearing the lenses. When the minus lenses were removed, the eyes recovered quickly to age-matched normal values. The consistent recovery response from myopia in juvenile eyes after minus-lens compensation, compared with the highly variable response to plus lens wear in age-matched juvenile animals suggests that eyes retain the ability to detect the myopic refractive state, but there is an age-related decrease in the ability of normal eyes to use myopia to slow their elongation rate below normal. If juvenile human eyes, compared with infants, have a similar difficulty in using myopia to slow axial elongation, this may contribute to myopia development, especially in eyes with a genetic pre-disposition to elongate.     

Total and corneal optical aberrations induced by laser in situ keratomileusis for hyperopia

PURPOSE: To evaluate changes induced by standard laser in situ keratomileusis (LASIK) for hyperopia on total and corneal optical quality. METHODS: Total and corneal aberrations were measured before and after standard hyperopic LASIK in 13 eyes (preoperative spherical equivalent refractive error +3.17 +/- 1.10 D). The Chiron Technolas 217C laser with PlanoScan was used. Total aberrations (measured using laser ray tracing) and corneal aberrations (estimated from a videokeratoscope) were described using Zernike terms. Root-mean-square wavefront error for both total and corneal aberrations, and through-focus Strehl ratio for the point spread function of the whole eye were used to assess optical changes induced by surgery. RESULTS: Third and higher order aberrations increased significantly after hyperopic LASIK (by a factor of 2.20 for total and 1.78 for corneal aberrations, for a 6.5-mm pupil). Spherical aberration changed to negative values (corneal average decreased by -0.85 +/- 0.48 microm and total average by -0.70 +/- 0.30 microm). Best Strehl ratio for the whole eye decreased by a factor of 1.84. Hyperopic LASIK induced larger changes than myopic LASIK, compared to an equivalent group of myopic eyes from a previous study. Induced corneal spherical aberration was six times larger after hyperopic LASIK, for a similar range of correction, and of opposite sign. As with myopic LASIK, changes in internal spherical aberration are of opposite sign to those induced on the corneal anterior surface. CONCLUSIONS: Hyperopic LASIK induced significant amounts of aberrations. The largest increase occurred in spherical aberration, which showed a shift (toward negative values) of opposite sign; increase was greater than for myopic LASIK.     

Ocular higher-order aberrations and mesopic pupil size in individuals screened for refractive surgery

AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥ 6.0 mm pupil, and pupil size measurements were performed under the mesopic condition. RESULTS: The mean values of HOAs, total spherical aberration and total coma in the myopic group were 0.369μm, ±0.233, 0.133± 0.112μm and 0.330±0.188μm, respectively. In the hyperopic group the mean values of HOAs, total spherical aberration and total coma were 0.418μm ±0.214, 0.202±0.209μm and 0.343±0.201μm, respectively. Hyperopes showed greater total HOAs (P<0.01) and total spherical aberration (P<0.01) compared to myopes. In age-matched analysis, only the amount of total spherical aberration was higher in the hyperopic group (P=0.05). Mesopic pupil size in the myopic group was larger (P≤0.05). CONCLUSION: The results suggested that significant levels of HOAs were found in both groups which are important for planning refractive surgeries on Iranians. There were significantly higher levels of total spherical aberration in hyperopes compared to myopes. Mesopic pupil size was larger in myopic group.     

Chick eyes compensate for chromatic simulations of hyperopic and myopic defocus: Evidence that the eye uses longitudinal chromatic aberration to guide eye-growth

Longitudinal chromatic aberration (LCA) causes short wavelengths to be focused in front of long wavelengths. This chromatic signal is evidently used to guide ocular accommodation. We asked whether chick eyes exposed to static gratings simulating the chromatic effects of myopic or hyperopic defocus would “compensate” for the simulated defocus.We alternately exposed one eye of each chick to a sine-wave grating (5 or 2 cycle/deg) simulating myopic defocus (“MY defocus”: image focused in front of retina; hence, red contrast higher than blue) and the other eye to a grating of the same spatial frequency simulating hyperopic defocus (“HY defocus”: blue contrast higher than red). The chicks were placed in a drum with one eye covered with one grating, and then switched to another drum with the other grating with the other eye covered. To minimize the effects of altered eye-growth on image contrast, we studied only the earliest responses: first, we measured changes in choroidal thickness 45 min to 1 h after one 15-min episode in the drum, then we measured glycosaminoglycans (GAG) synthesis in sclera and choroid (by the incorporation of labeled sulfate in tissue culture) after a day of four 30-min episodes in the drum.The eyes compensated in the appropriate directions: The choroids of the eyes exposed to the HY simulation showed significantly more thinning (less thickening) over the course of the experiment than the choroids of the eyes exposed to the MY simulation (all groups mean:−17 μm; 5 c/d groups: −24 μm; paired t-test (one-tailed): p = 0.0006). The rate of scleral GAG synthesis in the eye exposed to the HY simulation was significantly greater than in the eye exposed to the MY simulation (HY/MY ratio = 1.20; one sample t-test (one-tailed): p = 0.015). There was no significant interaction between the sign of the simulated defocus and either the spatial frequency or the presence of a +3 D lens used to compensate for the 33 cm distance of the drum.Although previous work has shown that chromatic cues to defocus are not essential for lens-compensation, in that chicks can compensate in monochromatic light, our evidence implies that the eye may be able to infer whether the eye is myopic or hyperopic from the different chromatic contrasts that result from different signs of defocus.     

Off-axis refraction and aberrations following conventional laser in situ keratomileusis

PURPOSE: To investigate off-axis refraction and aberrations following conventional laser in situ keratomileusis (LASIK) for myopia and hypermetropia. SETTING: School of Optometry, Queensland University of Technology, Australia. METHODS: Using an autorefractor, off-axis refractions were analyzed along the horizontal visual field between 35 degrees nasally and 35 degrees temporally in 1 eye each of 15 emmetropic subjects (-0.50 to +0.50 diopters [D]), 6 myopic subjects (-2.25 to -6.50 D), 6 hyperopic subjects (+1.50 to +3.00 D), 6 myopic LASIK patients (presurgical refraction -2.75 to -9.00 D), and 6 hyperopic LASIK patients (presurgical refraction +0.75 to +2.00 D). Wavefront sensing measured off-axis higher-order aberrations in 2 myopic LASIK patients. RESULTS: In myopic LASIK, the mean spherical components of refraction M became highly myopic away from the center of the visual field; in emmetropic and untreated myopic eyes, there were relatively small myopic shifts and hyperopic shifts, respectively. Off-axis 90-degree to 180-degree astigmatisms J180 in myopic LASIK subjects were greater than in untreated subjects. In hyperopic LASIK, there were mainly hyperopic shifts in M, opposite the direction in emmetropic and untreated hyperopic subjects. Off-axis J180 was less than in emmetropic and untreated hyperopic subjects. Some hyperopic LASIK patients had greater off-axis 45-degree to 135-degree astigmatisms J45 than patients in the other groups. In 2 myopic LASIK patients, Zernike root-mean-square 4th-order aberrations were higher than in the near-emmetropia group because of higher levels of positive spherical aberration. CONCLUSIONS: Off-axis aberrations can be dramatically affected by conventional myopic and hyperopic LASIK. In myopic LASIK, the increased off-axis refractive errors may have adverse effects on peripheral visual tasks that are dependent on off-axis refractive errors. The relatively low off-axis refractive errors in hyperopic LASIK patients may improve peripheral visual tasks.     

Optical quality of hyperopic and myopic phakic intraocular lenses

Aims:

To assess and compare the optical quality of the myopic and hyperopic implantable collamer lens (ICL) from its wavefront aberrations for different powers and pupil diameters.

Settings and Design:

Prospective study.

Material and Methods:

The wavefront aberrations of two myopic (−3 and −6 diopters (D)) and two hyperopic V4b ICLs (+3 and +6D) were measured in vitro. To assess and compare the optical quality of different powers of ICLs, we analyzed the root mean square (RMS) of total higher order aberrations (HOAs), trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration at 3- and 4.5-mm pupil. In addition, the point spread functions (PSFs) of each ICL evaluated were calculated from the wavefront aberrations at 3- and 4.5-mm pupil.

Statistical Analysis:

A Student''s t-test for unpaired data was used for comparison between myopic and hyperopic ICLs.

Results:

Myopic ICLs showed negative spherical aberration, in contrast hyperopic ICLs showed positive spherical aberration, which increases when the ICL power increases, due to the innate optical properties of the lens. All ICLs evaluated had negligible amounts of other aberrations. We did not find statistical significant differences in any Zernike coefficient RMS values analyzed between myopic and hyperopic ICLs at 3- and 4.5-mm pupil (P > 0.05).

Conclusions:

Myopic and hyperopic ICLs provide good and comparable optical quality for low to moderate refractive error. The ICLs evaluated showed values of wavefront aberrations clinically negligible to affect the visual quality after implantation.     

FS-LASIK与SMILE矫正近视术后角膜高阶像差的变化

目的　比较飞秒激光制瓣准分子激光原位角膜磨镶术（femtosecond-assisted laser in situ keratomileusis，FS-LASIK）与小切口飞秒激光基质透镜切除术（small incision lenticule extraction，SMILE）术后角膜高阶像差的变化。方法　选取行FS-LASIK患者22例（22眼）及行SMILE患者30例（30眼）作为研究对象，测量并对比2种术式患者术前及术后1周、1个月的角膜波前像差。结果　FS-LASIK术后1周球差、倾斜三叶草分别为(0.517±0.193)μm、(0.096±0.146)μm，与术前相比均增大，差异均有统计学意义（均为P<0.05）。FS-LASIK术后1个月球差、水平彗差、倾斜三叶草分别为（0.534±0.178)μm、（0.151±0.263)μm、（0.088±0.152)μm，与术前相比均增大，差异均有统计学意义（均为P<0.05）。SMILE术后1周球差、倾斜三叶草分别为（0.361±0.189)μm、（0.017±0.147)μm，与术前相比均增大，差异均有统计学意义（均为P<0.05）。SMILE术后1个月球差为（0.382±0.178)μm，与术前相比增大，差异有统计学意义（P<0.05）。术后1个月2组间球差、倾斜三叶草、总高阶像差均方根值差异均有统计学意义（t=3.043、2.647、2.391，均为P<0.05）。结论　FS-LASIK术后早期角膜高阶像差改变以球差、彗差、倾斜三叶草为主；SMILE术后早期角膜高阶像差改变以球差为主。FS-LASIK和SMILE术后早期球差、倾斜三叶草、总高阶像差有显著差异。     

角膜前表面高阶像差与年龄的相关性变化

目的 探讨和分析国人无器质性疾病眼角膜前表面高阶像差与年龄的相关性.方法 前瞻性临床研究.序贯选取年龄为11～50周岁、屈光度数为+0.50～-3.00 D且散光＜1.00 D的受检者201例,平均年龄(29.9±11.5)岁.根据受检者的年龄分为4组:11～20岁组、21～30岁组、31～40岁组和41～50岁组.采用鹰视角膜地形图仪测量角膜前表面像差,应用抛硬币法随机选取每名受检者一眼的数据.应用单因素方差分析比较各组角膜中央4、6和8 mm区域的彗差、三叶草像差、球差、二次散光和四叶草像差.结果 4、6、8 mm角膜区域的三叶草像差组间差异均有统计学意义(F=3.526、2.800、2.888,P均＜0.05),41～50岁组[(0.10±0.05)、(0.17±0.08)、(0.30±0.13)μm]明显大于21～30岁组[(0.08±0.04)、(0.13±0.06)、(0.22±0.11)μm,P均＜0.05].4 mm区二次散光41～50岁组[(0.03±0.02)μm]明显高于其余三组(P均＜0.05),6 mm区41～50岁组[(0.08±0.08)μm]与21～30岁组[(0.05±0.03)μm]之间差异有统计学意义(P＜0.05).8 mm区彗差和球差各年龄组间差异存在统计学意义(F=4.796、3.165,P均＜0.05),41～50岁组角膜彗差[(0.58±0.24)μm]、21～30岁组角膜球差[(0.63+0.16)μm]大于其他各组(P＜0.05).各组间四叶草像差差异无统计学意义.结论 不同年龄段的角膜前表面高阶像差存在着一定的差异,随着年龄的增大,球差逐渐减小而彗差逐渐增大.     

Einfluss des Alters auf die optischen Aberrationen des menschlichen Auges

BACKGROUND: Currently the influence of age on corneal and ocular aberrations is still insufficiently known. The aim of this clinical study was to compare age-related aberrations of human eyes. METHODS: In a prospective study 98 eyes of 49 healthy patients ranging from 17 to 65 years of age (38.6+/-10.0 years) were consecutively examined. The best corrected visual acuity ranged from 0.8 to 1.6; 48 eyes were emmetropic (SE+/-0.5 D), 42 eyes myopic (SE <-0.5 to -6.75 D), and 8 eyes hyperopic (SE >+0.5 to +3.88 D). The corneal aberrations were derived from corneal topography (Keratron Scout, Optikon). The measurement of ocular aberrations was performed with a Tscherning wavefront aberrometer (ORK, Schwind). The aberrations of the Zernike coefficients and RMS values (1st to 4th order) were determined. RESULTS: The mean corneal and ocular Zernike coefficients of higher order were smaller than 0.2 microm. There was an evident decrease of wavefront aberrations with increasing order. Higher order corneal aberrations were larger than the corresponding ocular aberrations. With increasing age higher optical errors increased in complexity, and the correlation of corneal and ocular aberrations decreased with significant differences. Although the corneal ocular RMS value of the 3rd and 4th order correlated in the younger group (r=0.51, p=0.0001), there was no correlation in the older group (r=-0.48, p=0.832). The influence of age caused a significant increase of ocular aberrations of the 3rd and 4th order, in particular a tenfold extension of coma (C07) (p=0.002), a twofold extension of spherical aberration (C12) (p=0.0001), and an increase of the 3rd and 4th order RMS values (p=0.001). CONCLUSIONS: Increased age induced an increase in optical aberrations of the eye, which demonstrates the influence of the lens on ocular aberrations. The combination of corneal and ocular diagnostic methods is recommendable for a better understanding of visual performance.     

Wave aberrations in rhesus monkeys with vision-induced ametropias

The purpose of this study was to investigate the relationship between refractive errors and high-order aberrations in infant rhesus monkeys. Specifically, we compared the monochromatic wave aberrations measured with a Shack-Hartman wavefront sensor between normal monkeys and monkeys with vision-induced refractive errors. Shortly after birth, both normal monkeys and treated monkeys reared with optically induced defocus or form deprivation showed a decrease in the magnitude of high-order aberrations with age. However, the decrease in aberrations was typically smaller in the treated animals. Thus, at the end of the lens-rearing period, higher than normal amounts of aberrations were observed in treated eyes, both hyperopic and myopic eyes and treated eyes that developed astigmatism, but not spherical ametropias. The total RMS wavefront error increased with the degree of spherical refractive error, but was not correlated with the degree of astigmatism. Both myopic and hyperopic treated eyes showed elevated amounts of coma and trefoil and the degree of trefoil increased with the degree of spherical ametropia. Myopic eyes also exhibited a much higher prevalence of positive spherical aberration than normal or treated hyperopic eyes. Following the onset of unrestricted vision, the amount of high-order aberrations decreased in the treated monkeys that also recovered from the experimentally induced refractive errors. Our results demonstrate that high-order aberrations are influenced by visual experience in young primates and that the increase in high-order aberrations in our treated monkeys appears to be an optical byproduct of the vision-induced alterations in ocular growth that underlie changes in refractive error. The results from our study suggest that the higher amounts of wave aberrations observed in ametropic humans are likely to be a consequence, rather than a cause, of abnormal refractive development.     

亚临床期圆锥角膜的高阶波前像差表现

目的:了解亚临床期圆锥角膜(subclinical keratoconus,SKC)患者的高阶波前像差的表现。方法:采用病例对照研究,收集20例32眼SKC患者作为SKC组,选取同时期20例40眼近视患者作为对照组,分别测量两组的波前像差,用t检验比较两组间的总高阶像差、球差和彗差的RMS值,用χ2检验比较两组间负性球差所占的比例。结果:SKC组的总高阶像差、球差和彗差的RMS值分别为0.637±0.488μm,0.276±0.135μm,0.364±0.205μm,对照组为0.394±0.282μm,0.113±0.084μm,0.148±0.079μm,两组间的差异有统计学意义(t=2.160,2.341,3.679;P<0.05);SKC组共有19眼表现为负性球差,对照组有9眼为负性球差,两组间的差异有统计学意义(χ2=10.17,P=0.001)。结论:亚临床期圆锥角膜患者的高阶像差明显增加,波前像差检查有助于亚临床期圆锥角膜的辅助诊断。     

近视散光眼角膜像差的特征及其影响因素分析

目的 研究近视散光眼角膜像差与屈光度、年龄的关系以及左右眼的对称关系,为眼部疾病的临床诊断和治疗提供客观依据.方法 随机选择大连医科大学附属第一医院眼科屈光中心欲行近视眼准分子激光手术的患者96例192只眼,术前进行眼科常规检查以及角膜波阵面像差检查.年龄18～48岁,平均(25.8±4.0)岁;包括男性54例108只眼,女性42例84只眼;球镜为-2.59～-10.74D,平均(-3.82±2.21)D;柱镜为-0.05～-2.44D,平均(-0.71±0.51)D.分析角膜像差与年龄、屈光度的关系以及角膜像差在左右眼之间的关系.结果 (1)Z13 RMS3项角膜像差随年龄增长而增加.(2)角膜球差和球镜屈光度呈正相关(r = 0.375,P < 0.01),角膜彗差和柱镜屈光度呈负相关(r = -0.335,P < 0.05),高度近视组角膜彗差和球镜屈光度呈负相关(r = -0.468,P < 0.01).(3)左右眼角膜像差呈对称关系.结论 角膜前表面波前像差分析,彗差与年龄呈正相关,球差和彗差分别与球镜度数和柱镜度数呈负相关,高度近视患者彗差与球镜屈光度呈负相关,双眼角膜像差有明显对称性.     

近视眼角膜高阶像差特征及与全眼高阶像差的关系

目的 探讨近视患者角膜高阶像差的特点及与全眼高阶像差的相关关系。方法 横断面研究。随机选取拟行角膜屈光手术的近视散光患者216例（216眼）,应用角膜波前像差分析仪与全眼波前像差分析仪（Schwind）在4 mm与6 mm瞳孔直径下分别对角膜与全眼进行波前像差测量。采用独立样本t检验比较分析角膜与全眼各主要高阶像差项的差异,采用Pearson直线相关分析患者角膜主要高阶像差项与球镜度、柱镜度、年龄的相关性,采用单因素方差分析比较散光顺规组与逆规组组间角膜高阶像差对比情况。结果 4 mm和6 mm瞳孔直径下,总高阶像差、总球差、水平彗差（C3+1）、球差（C40）在角膜与全眼之间差异均有统计学意义（4 mm：t=-2.364、-7.587、-2.197、-6.320,P＜0.05;6 mm：t=-4.794、-7.631、-7.945、-7.413,P＜0.01）。4、6 mm的角膜C40（顺规组与逆规组）与球镜度呈明显正相关（顺规组：r=0.211、0.255,P＜0.01;逆规组：r=0.697、0.562,P＜0.01）;逆规组各瞳孔直径角膜C3+1与柱镜度呈正相关（r=0.470、0.429,P＜0.05）。6 mm的顺规组与逆规组间的垂直彗差（C3-1）差异有统计学意义（P＜0.05）。结论 同一直径范围下角膜高阶像差各Zernike项均值从高到低依次为球差、垂直彗差、水平彗差、斜向三叶草、水平三叶草,与全眼像差排列顺序不甚相同。角膜与眼内像差可能存在补偿或迭加作用。顺规组与逆规组角膜高阶像差值略有不同,即使全眼散光表现为逆规,但角膜散光多为顺规,且与像差之间具有一定特异性关系。     

Characteristics of peripheral refractive errors of myopic and non-myopic Chinese eyes

Interest in peripheral refractive errors has increased as it was hypothesized that peripheral hypermetropia might provide a stimulus for axial elongation (Smith et al., 2005), this study was to determine relative peripheral refractive errors (RPRE) of the eyes of a group of Chinese children and adults. Central and peripheral (20°, 30°, 40° at nasal, temporal, superior and inferior meridians of retina) refractive errors were obtained from cyclopleged eyes of 40 children and 42 adults with a Shin-Nippon auto-refractor. Only right eyes were considered. Central spherical equivalent (M) was used to classify the eyes as Moderate Myopia (MM, −3.00 < M ? −6.00 D), Low Myopia (LM, −0.50 ? M ? −3.00 D), Emmetropia (E, −0.50 < M < +0.50 D) and Low Hypermetropia (LH, +0.50 < M ? +2.00 D). RPRE was calculated as the difference in M between the central and peripheral positions. The results showed that in both children and adults, horizontally, the RPRE profile for the MM group had a relative hypermetropic shift and in contrast, the profile for LH demonstrated a relative myopic shift. The difference in the profile between the MM and LH group was significant (p < 0.05). Also, the RPRE profile for MM group was different between adults and children with adult eyes showing greater amount of hypermetropic shift. Vertically, the RPRE profile of all the refractive error groups showed a myopic shift. Off-axis astigmatism increased and horizontally a shift from ‘with the rule’ to ‘against the rule’ astigmatism was observed for all groups. Our observations demonstrated that in Chinese eyes, the myopic group present a hyperopic shift in the periphery, the hypermetropic eye present a myopic shift and the emmetropic eyes present no differences to the fovea, which are similar to those reports in Caucasian eyes. The variations in the RPRE between various refractive error groups can be explained on the basis of eye shape.     

中度曲率性近视与轴性近视的高阶像差比较研究

目的：针对不同类型中度近视眼高阶像差的分析,探讨中度近视眼中曲率性近视与轴性近视高阶像差的差异。方法：采用前瞻性研究,选取单纯性中度近视眼患者39例56眼,将其分为两组：A组为中度曲率性近视眼组（11例/16眼）,平均年龄22±2岁,平均眼轴长度23.89±0.13mm,平均角膜曲率45.56±0.95D,平均屈光度4.58±0.82D;B组为轴性近视眼组共28例40眼,平均年龄22±3岁,平均眼轴长度25.82±0.44mm,平均角膜曲率41.93±0.85D,平均屈光度4.50±0.78D。利用波前像差仪获取入选患眼瞳孔分别为4,5,6mm时高阶像差值,进行分组比较。结果：A,B两组平均年龄与平均屈光度比较,差异无显著性（P〉0.05）;两组平均角膜曲率与平均眼轴长比较,差异有显著性（P〈0.05）。A组与B组在瞳孔为6mm时RMS3,RMS4,RMS6,RMSh,C12值比较,A组/B组分别为：0.165±0.064/0.098±0.045,0.127±0.034/0.059±0.025,0.040±0.014/0.028±0.010,0.218±0.059/0.129±0.040,0.137±0.057/0.048±0.037,差异有显著性（P〈0.05）。其余不同直径瞳孔下的高阶像差各值比较,前者均高于后者,差异均有显著性（P〈0.05）。结论：在正常及中度散大瞳孔下,中度近视眼中曲率性近视的彗差、球差、次级球差及总高阶像差均较轴性近视眼为大。     

Wavefront analysis of higher-order aberrations in patients with cataract

PURPOSE: To determine local refractive changes and higher-order aberrations in patients with nuclear or cortical cataract. SETTING: Osaka University Medical School, Osaka, Japan. METHODS: Wavefront analysis of both ocular and corneal aberrations was performed with the Hartmann-Shack aberrometer in 2 patients, a 22-year-old woman with bilateral developmental nuclear cataract and a 68-year-old woman with mild bilateral cortical cataract. RESULTS: Case 1 showed a delay in the wavefront that caused a myopic shift in the central pupillary area in both eyes, associated with the nuclear cataract. The spherical-like aberration (right eye, 36%; left eye, 21%) was greater than the coma-like aberration in both eyes. Case 2 showed an advancement of the wavefront that caused a hyperopic shift, especially in the lower temporal pupillary area, that was associated with the cortical cataract. The coma-like aberration (right eye, 63%; left eye, 52%) was greater than the spherical-like aberration in both eyes. The polarity of the third-order spherical aberration was negative in Case 1 and positive in Case 2. Corneal higher-order aberrations were small and had a different distribution than ocular higher-order aberrations in both patients. CONCLUSIONS: The Hartmann-Shack aberrometer was useful in detecting local refractive changes and higher-order aberrations in patients with mild cataract. The polarity and the absolute value of ocular higher-order aberrations may be useful parameters to characterize eyes with cataract.