Role of spherical aberration and coma in orthokeratology for myopia control / 国际眼科杂志(Guoji Yanke Zazhi)

As a highly prevalent global condition, myopia significantly impacts the ocular health of young individuals in China. Orthokeratology lens, as a rigid corneal contact lens, has demonstrated effective control over the progression of myopia; however, its mechanism of action remains incompletely elucidated. As one of the factors influencing visual acuity, higher-order aberrations will undergo marked changes after orthokeratology, with particular emphasis on the alterations in spherical aberrations and coma. The changes in corneal morphology induced by orthokeratology lead to significant positive increase in both spherical aberration and coma. Furthermore, the elevation of spherical aberration and coma demonstrates a negative correlation with the rate of axial length growth following orthokeratology. The interplay among spherical aberration, coma, defocus, accommodation, astigmatism, and pseudo-accommodation may constitute the underlying mechanism governing the control of myopia through orthokeratology.

Comparison of effective optical zone and corneal high order aberration following small incision lenticule extraction for different degrees of myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the effective optical zone(EOZ)and corneal high order aberrations(HOAs)after small incision lenticule extraction(SMILE)among low, moderate, and high myopic patients.METHODS:A total of 134 patients who had undergone SMILE at the Second People's Hospital of Foshan from February 2019 to February 2021 were recruited, with all right eyes enrolled. The patients were divided into low myopia group(SE >-3.00 D), moderate myopia group(-6.00 D< SE ≤-3.00 D), and high myopia group(SE ≤-6.00 D)according to the spherical equivalent(SE). The total HOA(tHOA), spherical aberration, coma, and EOZ were measured by Pentacam preoperatively and 1 mo postoperatively, and differences in tHOA, spherical aberration, coma, and EOZ among the three groups were analyzed.RESULTS: EOZ was smaller than programmed EOZ in all groups at 1 mo after SMILE. With the increase in corrected refractive error, the EOZ decreased further(P<0.05); The tHOA, spherical aberration, and coma were significantly higher than their corresponding preoperative values in all groups at 1 mo after surgery, and there were statistical differences in the spherical aberration of all the groups at 1 mo after surgery(P<0.05), except for that of the mild myopia group(P>0.05). The tHOA, spherical aberration and coma increased with corrected refractive errors; the difference in tHOA and spherical aberration was statistically significant among the three groups(all P<0.05). Coma in the high myopia group was significantly greater than that in the moderate myopia group and the mild myopia group(P<0.05). In addition, the coma in the moderate myopia group and the mild myopia group was not statistically significant(P>0.05).CONCLUSION: With the increase of the refractive power corrected by surgery, the postoperative EOZ reduced more after surgery, and the HOA of the cornea is increased; corneal HOA increases at 1 mo after SMILE.

The Effect of Monochromatic Aberrations of the Cornea on Contrast Sensitivity under Photopic and Mesopic Conditions

Purpose: Vision is one of the most important senses. The first stage of vision is the creation of the observed object抯 image on the retina. The quality of the retinal image is affected by several factors, such as diffraction, sampling on the retina, chromatic aberration, scattering and higher order aberrations. The measurement of the quality is achieved both with subjective (visual acuity, contrast sensitivity) and objective methods (PSF, MTF, Strehl ratio, RMS). The purpose of this project is the measurement of higher order aberrations of the anterior corneal surface (with a Placido corneal topographer) and of the contrast sensitivity (with a Pelli Robson optotype). Then, we will try to find if there is a correlation between them.Methods and Materials: 20 persons participated in this survey, divided in two groups of 10 persons each. The first group (group 1) included subjects up to 39 years old and the second group (group 2) from 40 years and up. The participants didn抰 have any pathological problems, except lower order refractive errors. Both eyes of each individual were included in the procedure. First, the higher order aberrations of the anterior corneal surface were measured, with the implementation of a Placido corneal topographer. This was followed by a measurement of the contrast sensitivity. The whole procedure took place under two lighting conditions, both photopic and mesopic. The examination presentation of the higher order aberrations is performed with the use of Zernike polynomials.Results: The results of the measuring procedure showed that for the first group, under photopic conditions (luminance 32.70 cd/m2) the mean value (� standard deviation) for the higher order aberrations RMS and decimal logarithm contrast sensitivity was 0.073 � 0.018?m and 1.54 � 0,16 (contrast 2.88 � 1.24%) respectively. For the second group the corresponding values were 0.080 � 0.036?m and 1.59 � 0.16 (contrast 2.57 � 1.24%). Accordingly, under mesopic conditions (luminance 1.14 cd/m2) the values for the first group were 0.252 � 0.064 ?m and 1.27 � 0.15 (contrast 5.37 � 2.06%), while for the second were 0.253 � 0.069?m and 1.32 � 0.12 (contrast 4.79 � 1.35%). Spherical aberration and coma (horizontal and vertical) were also measured for both groups under photopic and mesopic conditions. The results showed that for the first group, under photopic conditions, RMS for coma and spherical aberration is 0.033 � 0.014 ?m and 0.022 � 0.011 ?m respectively, while for the second group 0.041 � 0.027 ?m and 0.024 � 0.008 ?m. Under mesopic conditions, the relevant results are 0.139 � 0.065 ?m and 0.124 � 0.035?m for the first group and 0.149 � 0.066 ?m and 0.107 � 0.038 ?m for the second group.Finally, we should mention here that the equivalent defocus error corresponding to the higher order aberration RMS was estimated. The results for all the participants (without age separation), are 0.23 � 0.09D (photopic conditions) and 0.28 � 0.07D (mesopic conditions).Conclusions: From the statistical analysis of the results we conclude that there exists a symmetry between left and right eyes regarding higher order aberrations. Furthermore, it seems that age is not a significant factor for differences on the magnitude of higher order aberrations both under photopic and mesopic conditions as well. Similar conclusions are also reached for the contrast sensitivity measurements. In addition, we have observed that a correlation exists between the higher order aberrations of the anterior corneal surface and the contrast sensitivity, for both photopic and mesopic conditions. Correlation also exists between coma and contrast only under photopic conditions. But there is no significant correlation between spherical aberration and contrast. The age difference of these two groups has not an effect on the results. Finally, the equivalent defocus is too small, both for photopic and mesopic conditions and between each other, in order to be clinically significant.

Comparison of visual performance of monofocal intraocular lenses with different asphericities

Objective@#To compare the visual performance and patient-reported outcomes of three types of monofocal intraocular lenses (IOL) with different asphericities.@*Methods@#This cross-sectional, comparative study comprised of 62 pseudophakic eyes divided into three groups corresponding to the IOL that they were previously implanted with (Tecnis ZCB00 negative aspheric IOL, EnVista MX60 neutral aspheric IOL and Akreos Adapt spheric IOL). Mean refractive spherical equivalent (MRSE), best-corrected far visual acuity (BCVA), spherical aberration (SA), contrast sensitivity (SC), halo and starburst, and responses to a qualitative questionnaire (NEI-RQL) were measured.@*Results@#There was no significant difference in MRSE (P=0.74) and BCVA (P=0.52) among the three groups. There was a statistically significant difference (P=0.00) in mean internal (lens) SA, measured through a 5mm pupil, among Tecnis (-0.150 μm), EnVista (+0.022 μm) and Akreos Adapt (+0.094 μm). Compared to the Akreos Adapt, the Tecnis and EnVista groups had significantly better CS at 6 CPD and 12 CPD under mesopic testing without glare (P= 0.01) and at 6 CPD mesopic testing with glare (P=0.04). Halo scores were insignificant among the three groups. However, starburst scores were significantly worse in the Akreos Adapt IOL than the Tecnis and EnVista (P=0.01). There was no difference in questionnaire responses among the three groups.@*Conclusion@#The negative aspheric and neutral aspheric lenses showed significantly lower SA resulting in better CS in mesopic conditions and better starburst scores. MRSE, BCVA and subjective satisfaction were statistically similar regardless of the type of monofocal intraocular lens

Effect of eccentricity of overnight orthokeratology lenses on axial growth and visual quality / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To explore the effect of eccentricity of overnight orthokeratology(OK)lenses on 2-year eye axial growth and visual quality.<p>METHODS:Based on the degree of eccentricity of OK lenses, patients were divided into three groups: a low degree of eccentricity group(degree of eccentricity ≤0.5 mm), a group of moderate eccentricity(eccentric degree >0.5-≤1.0 mm)and a group with a high degree of eccentricity(eccentric degree >1-≤1.5 mm). The degree of eccentricity of the OK lens, spherical equivalent(SE), the uncorrected visual acuity after wearing OK lenses(UCVA), axial length before and after wearing OK lenses(AL), total higher-order aberrations(HOA), comas, and spherical aberrations(SA)for 3 mm pupils were analyzed. The difference among the three groups for all parameters was compared using the Kruskal-Wallis H Rank-Sum test.<p>RESULTS:The study retrospectively analyzed 75 cases(139 eyes). In the low eccentricity group(53 eyes), the mean age was 11.4±2.4 years, SE was -3.24±1.48 D, and AL was 24.85±1.01 mm. In the moderate eccentricity group(53 eyes), the mean age was 11.4±2.2 years, SE was -3.22±1.29 D, and AL was 25.15±0.92 mm. In the high eccentricity group(31 eyes), the mean age was 11.5±1.9 years, SE was -3.54±1.43 D, and AL was 24.95±0.84mm. After two years, there was no significant difference in the changes of the axis among the three groups(<i>P</i>=0.089). The HOA, SA, and coma in the high eccentric group were significantly higher than in the middle eccentric group(<i>P</i><0.05). The HOA, SA, and coma in the high eccentric group were also significantly higher than those in the low eccentric group(<i>P</i><0.05).<p>CONCLUSION:For OK lenses, it is unnecessary to strictly require the absolute centralization of the lens position. An unnecessary change of the lenses may delay the eye-axis control. However, the balance between axial control and visual quality should be assessed.

Analysis of corneal spherical aberration in age-related cataract / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To investigate the distribution of corneal spherical aberration in age-related cataract.<p>METHODS: Retrospective study. Totally 217 cases of age related cataract(217 eyes)were collected in the Central Hospital of Kaifeng from August 2017 to August 2018. Patients were divided into 3 groups according to age: 50-60 years(63 eyes)in group Ⅰ, 61-70 years(107 eyes)in group Ⅱ, 71-80 years(47 eyes)in group Ⅲ. Pentacam anterior segment analysis was used to measure the anterior and posterior corneal K-readings. The corneal spherical aberration of anterior, posterior and total were calculated on an area of 6mm diameter by Zernike analysis and a descriptive study was used.<p>RESULTS:The Mean±SD of total corneal spherical aberration was 0.311±0.098μm for all the patients. Statically significant were found for the anterior and total corneal spherical aberration(<i>F</i>=34.434, 32.896; <i>P</i><0.05). The anterior, posterior corneal K-readings and posterior corneal spherical aberration had no correlation with age(<i>r</i>=0.040, 0.066, 0.097, <i>P</i>>0.05). The anterior and total corneal spherical aberration were positively correlated with age(<i>r</i>=0.506, 0.509, <i>P</i><0.05).<p>CONCLUSION:The total corneal spherical aberration in age-related cataract was slightly higher than that before. The anterior and total corneal spherical aberration increased with age, and then the posterior corneal spherical aberration was not.

Comparative study of corneal spherical aberration and curvature measured by iTrace and Pentacam / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the difference and consistency between iTrace and Pentacam in measuring corneal spherical aberration(SphA)and curvature.<p>METHODS: The corneal spherical aberration and curvature were measured by iTrace and Pentacam in 63 cases(125 eyes)separately, and the SphA, the minimum corneal curvature(K1), maximum corneal curvature(K2)and corneal astigmatism(CA)were recorded respectively. Paired <i>t</i>-test was used for statistical analysis of econometric data, Bland-Altman analysis was used to evaluate the consistency of measurement results(SphA and curvature)measured by iTrace and Pentacam.<p>RESULTS: The measurement result of SphA, K1, K2 and CA were(0.230±0.086)μm,(43.01±2.38)D,(44.08±2.48)D and(1.03±0.57)D measured by iTrace, and(0.247±0.114)μm,(42.88±1.44)D,(43.86±1.51)D and(1.07±0.62)D measured by Pentacam, there was no significant difference of the measurement result of SphA, K1, K2 and CA between iTrace and Pentacam(<i>P</i>>0.05). The difference of SphA, K1, K2 and CA between iTrace and Pentacam was close to 0, the consistency was good because of the narrow 95% confidence interval.<p>CONCLUSION:There is no significant difference of the measurement result between iTrace and Pentacam, the consistency is good, and both can be used as a mutual reference in clinical.

Effects of SMILE and Trans-PRK on corneal higher order aberrations after myopic correction / 国际眼科杂志(Guoji Yanke Zazhi)

·AIM:To observe the effects of small incision lenticule extraction (SMILE) and trans-epithelial photorefractive keratectomy (Trans-PRK) on corneal horizontal coma, vertical coma, and spherical aberration and total higher order aberrations after refractive correction for myopia. ·METHODS: This was a prospective non-randomized cohort study. The cohort included 40 patients (80 eyes) with myopia, who received refraction correction surgery from December 2016 to February 2017 in Leshan Ophthalmic Center. Twenty patients (40 eyes) received SMILE surgery and the other 20 patients (40 eyes) received Trans-PRK surgery. Corneal aberrations were determined by a high-resolution Pentacam Scheimpflug camera before the surgery and at 1 and 3mo after the operation. Statistical analyses were performed using analysis of variance of repeated measures. · RESULTS: At 1 and 3mo post - operation, the uncorrected visual acuity in both groups was better than or equal to the preoperative best corrected visual acuity. The preoperative corneal aberrations showed no significant difference between the two groups (P>0.05). Significantly higher aberration was found after the surgery in both groups (P < 0. 05), however, no significant difference in higher aberration was found between 1 and 3mo post - operation (P > 0. 05). Post - operation, horizontal and vertical coma had no significant difference between the two groups (P>0.05), while SMILE group showed lower spherical aberration and lower total higher order aberration than Trans-PRK group (P<0.05). ·CONCLUSION: Both SMILE and Trans-PRK increase corneal aberration and their effects on horizontal and vertical coma are similar. However, SMILE has a minor influence on spherical aberration and total high order aberration than Trans-PRK.

Clinical study inpatient-reported outcomes after binocular implantation of aspheric intraocular lens of different negative spherical aberrations

Objective To compare patient-reported outcomes after implantation of the ZA9003 intraocular lens (IOLs), or the MCX11 ASP IOLs or the spherical IOLs (HQ-201HEP). Methods Prospective nonrandomized controlled trial was used. A total of 105 patients (210 eyes) were divided into three groups according to the type of IOLs: ZA9003 (35 patients, 70 eyes), MCX11 ASP (35 patients, 70 eyes) or HQ-201HEP (35 patients, 70 eyes). The main outcome was scores of Catquest nine-item short-form questionnaire. Additional outcome was best corrected visual acuities, spherical aberration (SA) and total higher-order aberrations (HOAs). Results The global score was significantly lower in the spherical IOL group than the aspherical IOL group of −020 μm SA (P 0.05). Significant differences were also found in question 2, question 5, question 6 and question 8 between the spherical IOLs and the aspherical IOLs. Conclusion Implantation of an aspherical IOL could improve vision-related quality of life compared with a spherical IOL. However, there were no statistically significant differences in vision-related quality of life between aspheric IOLs with different negative spherical aberrations.

Clinical study inpatient-reported outcomes after binocular implantation of aspheric intraocular lens of different negative spherical aberrations

OBJECTIVE@#To compare patient-reported outcomes after implantation of the ZA9003 intraocular lens (IOLs), or the MCX11 ASP IOLs or the spherical IOLs (HQ-201HEP).@*METHODS@#Prospective nonrandomized controlled trial was used. A total of 105 patients (210 eyes) were divided into three groups according to the type of IOLs: ZA9003 (35 patients, 70 eyes), MCX11 ASP (35 patients, 70 eyes) or HQ-201HEP (35 patients, 70 eyes). The main outcome was scores of Catquest nine-item short-form questionnaire. Additional outcome was best corrected visual acuities, spherical aberration (SA) and total higher-order aberrations (HOAs).@*RESULTS@#The global score was significantly lower in the spherical IOL group than the aspherical IOL group of -020 μm SA (P  0.05). Significant differences were also found in question 2, question 5, question 6 and question 8 between the spherical IOLs and the aspherical IOLs.@*CONCLUSION@#Implantation of an aspherical IOL could improve vision-related quality of life compared with a spherical IOL. However, there were no statistically significant differences in vision-related quality of life between aspheric IOLs with different negative spherical aberrations.

Analysis on corneal spherical aberration in patients with cataract in Kaifeng area / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To find out the mean corneal spherical aberration and its changes with age in Kaifeng population. METHODS: A total of 466 eyes of 427 Kaifeng subjects with cataract, whose age ranged from 52 to 75 years old, were divided into three groups according to the age. All the subjects were included in measuring K-readings of cornea, the corneal anterior and posterior surfaces of the spherical aberration and the total corneal spherical aberration using Pentacam(Oculus, Germany) at the 6-mm optical zone. RESULTS:The mean corneal spherical aberration( CSA) of the whole groups was 0. 339±0. 153μm. Patients from 50 to 60 years old had CSA of 0. 322±0. 137μm, 0. 326±0.157μm was the CSA of the patients from 60 to 70 years old, while those from 70 to 80 years old have a CSA of 0.401 ± 0. 182μm. The corneal K - readings had no correlation with the total corneal spherical aberration ( r=0. 034, P>0. 05), anterior surfaces CSA, posterior surfaces and total CSA were positively correlated with age ( r =0.253, 0. 327, 0. 233, all P CONCLUSION:CSA is varied among the population and CSA of elderly in Kaifeng area are slightly higher than white people, and positively correlated with age.

Predictibilidad en la inducción de aberración esférica basada en la asfericidad corneal post LASIK en miopes / Predictability of spherical aberration based on corneal asphericity after myopic laser customized corneal ablation

Purpose: To determine the predictability of postoperative ocular spherical aberration (Z 4,0) based on postoperative corneal asphericity (Q value) in patients with myopic astigmatism. Design: Case series, retrospective. Methods: Wavefront-guided laser in situ keratomileusis (LASIK) was performed in 40 eyes of 23 patients using the Schwind Esiris Excimer Laser. Patients were evaluated preoperatively and 3 months postoperatively. Spherical aberration was measured with a COAS Shack-Hartmann wavefront sensor, and determined for a 6 mm analysis diameter zone. Corneal asphericity was measured with the Orbscan II topographer. Correlation and linear regression analysis was performed. A P value less than 0.05 was considered statistically significant. Results: Treated eyes had a mean manifest spherical error of ­2.98 + 1.36 Diopters (D), and a mean manifest astigmatic error of 0.52 + 0.46 D. The mean Q was -0.30 + 0.13 preoperatively and +0.03 + 0.22 postoperatively. The mean spherical aberration was 0.054 + 0.109 microns preoperatively and 0.262 + 0.135 microns postoperatively. We found a positive statistically signifi cant correlation between postoperative Q value and postoperative spherical aberration (r=0.367) (P=0.02). The postoperative Q value showed a low correlation with postoperative spherical aberration (R2=0.14). Conclusions: There was an increase in corneal asphericity and spherical aberration after surgery. Postoperative corneal asphericity is mildly associated with postoperative spherical aberration. Predictability of postoperative spherical aberration in terms of correlation with postoperative Q value was poor, suggesting that corneal asphericity is not a major predictor of spherical aberration induction.

Clinical Results and Optical Quality of Diffractive Multifocal Intraocular Lens

PURPOSE: To compare postoperative clinical outcomes, optical quality, and patient satisfaction between two types of diffractive multifocal intraocular lens (IOL, Acri Lisa 366D and Acrysof ReSTOR +3.00 D). METHODS: In a total of 68 eyes, one of two diffractive multifocal IOL (Acri Lisa 366D and Acrysof ReSTOR +3.00 D) was implanted after cataract extraction. Visual acuity was measured postoperatively at one week, 1 month, and 6 months. Contrast sensitivity, wavefront aberration, and visual function were determined via questionnaire at postoperative 1 month. RESULTS: Intermediate visual acuity of Acri Lisa 366D and Acrysof ReSTOR at 6 months were 0.31 +/- 0.14, and 0.24 +/- 0.11 (log MAR), respectively. At 6 months, near and distant visual acuity results showed no significant differences between the two groups. The photopic contrast sensitivity of Acri Lisa 366D at 6 cycles/degree was 55.36 +/- 7.40 and showed significant differences with Acrysof ReSTOR (47.25 +/- 9.67). The mesopic contrast sensitivity values of Acri Lisa 366D and Acrysof ReSTOR were 40.26 +/- 11.38 and 28.97 +/- 10.45, respectively, and the spherical aberration values were 0.037 +/- 0.039 microm and 0.105 +/- 0.066 microm. The spherical aberration of Acri Lisa 366D was significantly lower than that of Acrysof ReSTOR. Total and high order aberration, coma, and trefoil show no significant differences between the two groups. CONCLUSIONS: The Acri Lisa 366D multifocal IOL showed better contrast sensitivity and spherical aberration compared to Acrysof ReSTOR multifocal IOL, which had an effective intermediate visual acuity.

The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia

PURPOSE: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. METHODS: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. RESULTS: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. CONCLUSIONS: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.

The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia

PURPOSE: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. METHODS: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. RESULTS: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. CONCLUSIONS: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.

Comparison of Keratometry and Corneal Higher Order Aberrations between Scout Videokeratoscope and Pentacam Scheimpflug Camera

PURPOSE: To investigate the correlations of keratometry and corneal high order aberrations (HOAs) between the Keratron Scout videokeratoscope and the Pentacam HR Scheimpflug camera. METHODS: From December 2012 to February 2013, keratometry and corneal HOAs were determined using the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera in 23 healthy individuals (46 eyes). RESULTS: Average keratometry showed high correlation with 95% confidence interval -0.155 +/- 0.37 between the Keratron Scout and Pentacam HR. When comparing HOAs of the Keratron Scout and total corneal HOAs of Pentacam HR, total root-mean-square (RMS), and spherical aberration were positively correlated between the 2 devices (r = 0.67, p < 0.001 and r = 0.74, p < 0.001, respectively). When comparing HOAs of Keratron Scout and anterior corneal HOAs of Pentacam HR, total RMS, spherical aberration and coma were positively correlated between the 2 devices (r = 0.62, p < 0.001, r = 0.81, p < 0.001, and r = 0.52, p = 0.047, respectively). CONCLUSIONS: Although the 2 devices are based upon different principles, the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera showed positive correlations in keratometry, total RMS, spherical aberration, and coma. Both devices may be useful for clinical applications.

Comparison of Keratometry and Corneal Higher Order Aberrations between Scout Videokeratoscope and Pentacam Scheimpflug Camera

PURPOSE: To investigate the correlations of keratometry and corneal high order aberrations (HOAs) between the Keratron Scout videokeratoscope and the Pentacam HR Scheimpflug camera. METHODS: From December 2012 to February 2013, keratometry and corneal HOAs were determined using the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera in 23 healthy individuals (46 eyes). RESULTS: Average keratometry showed high correlation with 95% confidence interval -0.155 +/- 0.37 between the Keratron Scout and Pentacam HR. When comparing HOAs of the Keratron Scout and total corneal HOAs of Pentacam HR, total root-mean-square (RMS), and spherical aberration were positively correlated between the 2 devices (r = 0.67, p < 0.001 and r = 0.74, p < 0.001, respectively). When comparing HOAs of Keratron Scout and anterior corneal HOAs of Pentacam HR, total RMS, spherical aberration and coma were positively correlated between the 2 devices (r = 0.62, p < 0.001, r = 0.81, p < 0.001, and r = 0.52, p = 0.047, respectively). CONCLUSIONS: Although the 2 devices are based upon different principles, the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera showed positive correlations in keratometry, total RMS, spherical aberration, and coma. Both devices may be useful for clinical applications.

Clinical Outcomes of Cataract Surgery with Correction of Corneal Spherical Aberration

PURPOSE: To evaluate preoperative and postoperative spherical aberrations after cataract surgery based on selecting spherical or aspheric intraocular lens (IOL) according to preoperative corneal aberration. METHODS: The medical records of patients who underwent phacoemulsification and IOL implantation in the posterior chamber by a surgeon (H.J.C) were reviewed (68 patients, 97 eyes). IOL was selected based on preoperative corneal spherical aberration measured by corneal topography (ATLAS 9000, Carl Zeiss). The target postoperative total ocular spherical aberration was set to zero (0) and one of the following lenses was chosen: Acrysof SA60AT (n = 25), Acrysof IQ (n = 36) or Tecnis(R) ZCB00 (n = 36). The Wavescan aberrometer and the corneal topography were obtained postoperatively. Absolute prediction errors of postoperative total ocular spherical aberration were analyzed. RESULTS: Preoperative corneal spherical aberration was 0.241 microm; total postoperative ocular spherical aberration was 0.0509 microm (Acrysof SA60AT: 0.0954 microm, Tecnis(R) ZCB00: 0.0374 microm, Acrysof IQ: 0.0335 microm). Postoperative corneal spherical aberration was 0.232 microm, which was not significantly different from the preoperative value (p = 0.199). Postoperative ocular spherical aberration was 0.051 microm; 0.095 microm (Acrysof SA60AT), 0.034 microm (Acrysof IQ), and 0.037 microm (ZCB00). The reducing amounts of spherical aberration were 0.185 microm (Acrysof IQ) and 0.311 microm (ZCB00). The overall absolute prediction error was 0.068 microm. The absolute prediction error of the Acrysof SA60AT group was 0.092 microm, Tecnis(R) ZCB00 group was 0.067 microm and Acrysof IQ group was 0.054 microm. There was no significant difference among the 3 groups (p = 0.089). CONCLUSIONS: Aspheric IOLs can efficiently reduce total ocular spherical aberrations according to preoperative corneal spherical aberrations.

Effect of different ocular spherical aberration on visual performance after phacoemulsification / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the visual acuity and contrast sensitivity of eyes with different corneal spherical aberration implanted with the same aspherical IOL and evaluate the effect of different ocular spherical aberration on visual performance after phacoemulsification. METHODS:It was a prospective case series study. Forty-six eyes of thirty-nine age-related cataract patients in our department were included. The patients were divided into 3 groups according to the value of preoperative corneal spherical aberration. Eyes with corneal spherical aberration≤0. 2μm were assigned to group A, those with corneal spherical aberration >0. 2μm and ≤0. 3μm to group B, and those with corneal spherical aberration≥ 0. 3μm to group C. All patients underwent phacoemulcification and recieved AcrySof IQ aspheric IOL. Uncorrected visual acuity ( UCVA ) , best-corrected visual acuity( BCVA) , contrast sensitivity, and total ocular higher - order aberrations for a 6. 0mm pupil were recorded 3mo postoperatively. ANOVA were used to analyze the data. RESULTS: There were no significant differences in UCVA and BCVA between the 3 groups (P=0. 287, 0. 115). Contrast sensitivity was no statistically significant difference between the 3 groups at any spatial frequency under photopic、 mesopic, and mesopic with glare conditions (P>0. 05). With a 6. 0mm pupil diameter, root mean square values for total ocular higher - order aberrations were lower in groups A and B than that in group C (P=0. 000). The difference of total ocular spherical aberration was statistically significant between the 3 groups (P=0. 000). Coma and trefoil were similar between the groups (P=0. 788,0. 590), with no statistically significant differences.CONCLUSION:Implantation of the same aspherical IOL in eyes with different corneal spherical aberration results in similar visual acuity and contrast sensitivity. Small differences of ocular spherical aberration after phacoemulsification have no effect on visual performance.

Comparisons of Clinical Results after Implantation of Three Aspheric Intraocular Lenses

PURPOSE: To compare the clinical 3 months postoperative results of three different 1-piece aspheric intraocular lenses (IOLs): AcrySof IQ SN60WF (Alcon Laboratories, INC, Fort Worth, TX), TECNIS 1-piece ZCB00 (AMO Inc., Santa Ana, CA) and the newly developed enVista MX60 (Bausch & Lomb, Rochester, NY). METHODS: In a total of 62 eyes, 1 of the 3 1-piece aspheric IOLs, AcrySof IQ SN60WF, TECNIS 1-piece ZCB00 or enVista MX60 was implanted after cataract extraction. Best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), and spherical equivalent were assessed 3 months postoperatively. Total spherical aberration, high order aberration, and modulation transfer function were analyzed. RESULTS: There were no significant differences of UCVA, BCVA, the accuracy of postoperative refractive power, and modulation transfer function among the 3 IOLs. Higher order aberrations of the entire eye and internal optics showed almost no significant differences. CONCLUSIONS: The newly developed IOL, enVista MX60, showed equivalent clinical outcomes as both AcrySof IQ SN60WF and TECNIS 1-piece ZCB00.