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AIM: To compare the postoperative efficacy of corneal wavefront-guided femtosecond laser-assisted excimer in situ keratomileusis(FS-LASIK)in the treatment of myopia patients with different degrees of astigmatism and the changes of corneal higher order aberration.METHODS: A total of 133 patients(265 eyes)with myopia and astigmatism were enrolled in this retrospective study. All of them underwent corneal wavefront-guided FS-LASIK surgery for the first time in Aier Eye Hospital(Kunming)from April to October 2020. The patients were divided into three groups according to the different astigmatism: Low astigmatism group: astigmatism ≤1.0D, 62 cases(124 eyes), medium astigmatism group: a total of 54 cases(107 eyes)with astigmatism was 1.25-2.0D, high astigmatism group: a total of 17 cases(34 eyes)with astigmatism ≥2.25D. Visual acuity and refraction were recorded before surgery and 3mo after the surgery and the cornea of the patients was measured by Pentacam three-dimensional corneal topography. Record total higher order aberrations(root mean square), spherical aberration, horizontal coma, vertical coma, horizontal clover and oblique clover in the 6mm diameter range of the cornea. The postoperative effects of the three groups of patients were observed and the changes of corneal high order aberration before and after surgery were compared. RESULTS: The validity index of visual acuity in the three groups of patients was all greater than 1.1 and the residual diopter was all within ±0.30D. The residual diopter in the low astigmatism group was the least than that of the other two groups(P<0.05). At 3mo after surgery, the corneal total higher order aberration, spherical aberration and vertical coma of the three groups were all increased compared with those before surgery(P<0.05). The spherical aberration increase in the high astigmatism group was less than that in the other two groups(P<0.05).CONCLUSION: Corneal wavefront-guided FS-LASIK surgery is safe and effective in the treatment of myopia with different degrees of astigmatism, and the effect is also accurate for patients with high astigmatism. The degree of of preoperative astigmatism is not responsible for increased corneal higher order aberration after the surgery.
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Objective:To compare the changes of corneal asphericity and higher-order aberrations after smart pulse technology-assisted transepithelial photorefractive keratectomy (Smart) for low and moderate myopia and to investigate the changes in the shape of the front corneal surface in patients with different diopters.Methods:A non-randomized controlled study design was used.Ninety-eight eyes of 54 patients with moderate or low myopia who underwent Smart surgery in Tianjin Medical University Eye Hospital from November 2018 to March 2019 were included.The 41 eyes of 23 patients with low myopia were set as the low-myopia group, and 57 eyes of 31 patients with moderate myopia were assigned as the moderate-myopia group.The Pentacam anterior segment analysis system was used to measure Q value, index of surface variance (ISV), corneal higher-order aberration (HOA), corneal vertical coma (Z 3-1), corneal horizontal coma (Z 31) and spherical aberration (Z 40) before surgery, 1 month and 3 months after surgery.The anterior surface morphology was compared between the low-myopia and moderate-myopia group.Pearson correlation analysis was used to analyze the correlations between measurement parameters.The study protocol was approved by an Ethics Committee of Tianjin Medical University Eye Hospital (No.2019KY-17). Written informed consent was obtained from each patient before surgery. Results:Corneal Q value, ISV, HOA and Z 40 were 0.445±0.191, 26.973±5.611, 0.671±0.142 and 0.384±0.188, respectively, in the low-myopia group at one month after surgery, which were significantly increased than corresponding preoperative values of -0.273±0.817, 13.784±2.376, 0.433±0.687 and 0.231±0.062 (all at P<0.05). Corneal Q value, ISV, HOA and Z 40 were 0.693±0.203, 34.038±5.773, 0.874±0.216 and 0.520±0.129, respectively, in the moderate-myopia group at one month after surgery, which were significantly increased than corresponding preoperative values of -0.309±0.104, 14.838±3.992, 0.409±0.081 and 0.228±0.089 (all at P<0.05). Corneal Q values, ISV, HOA and Z 40 in the moderate-myopia group were higher than those in the low-myopia group at different time points after surgery, showing significant differences between the two groups (all at P<0.05). There was no significant difference in postoperative 1-month and 3-month corneal Z 3-1 and Z 31 between the two groups (both at P>0.05). The results of correlation analysis showed that there were no significant differences in ΔQ value and ΔISV between the two groups, both of which were negatively correlated with spherical equivalent (ΔQ value: low-myopia group: r=-0.364, P=0.044; moderate-myopia group: r=-0.589, P<0.01; ΔISV: low-myopia group: r=-0.298, P=0.039; moderate-myopia group: r=-0.409, P=0.022). ΔQ value and ΔZ 40 were positively correlated in the moderate-myopia group ( r=0.348, P=0.009); there was no significant correlation between ΔQ value and ΔZ 40 in the low-myopia group ( r=0.180, P=0.266). Conclusions:The corneal high-order aberrations and ISV after Smart are increased in comparison with preoperative values in the low-myopia and moderate-myopia eyes, and the corneal Q values change from negative to positive.The effect of Smart on corneal asphericity is less in the low-myopia eyes.
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@#AIM: To study the efficacy and safety of accelerated collagen cross-linking in keratoconus.<p>METHODS: Medical records of keratoconic corneas underwent accelerated collagen cross-linking at King Chulalongkorn Memorial Hospital, Thailand between April 2015 and August 2018 were reviewed. Preoperative and postoperative data at 1a of visual acuity, auto-refraction, corneal topography, higher-order aberrations(HOA), topometric indices and corneal densitometry were evaluated. Age of 24 and 30 years old, maximum keratometry value(Kmax)of 55 D, and baseline best corrected visual acuity(BCVA)of 20/40(or 0.3 in LogMAR unit)were used as cut-off values to highlight the cross-linking effects. The effect of age, preoperative Kmax and BCVA were analyzed. The association between the change of corneal densitometry and other factors including preoperative Kmax, Kmean, manifest refraction spherical equivalent(MRSE), visual acuity, thinnest pachymetry, the change in Kmax, and the change of those parameters were also analyzed. <i>P</i><0.05 was considered statistically significant.<p>RESULTS: One hundred and fifty-five patients(185 eyes)were included. One hundred and nineteen patients were male and thirty-six patients were female. According to Amsler-Krumeich classification, stages 1 and 2 were dominant(37.84% and 35.14% respectively). At 1a, mean LogMAR uncorrected visual acuity(UCVA)improved by 0.1(<i>P</i><0.05). The number of eyes of which postoperative BCVA improved more than 0.2 LogMAR was higher in the worse baseline BCVA group(preoperative BCVA ≥0.3)compared to the better baseline BCVA group(preoperative BCVA < 0.3)(78.26% <i>vs</i> 21.74%, <i>P</i><0.05). Mean Kmax decreased from baseline by 2.36 diopters(D)(<i>P</i><0.05). Seventy-three percent of the eyes of which Kmax reduced more than 2.0 D had preoperative Kmax ≥55 D. Corneal HOA at 6 mm from corneal apex decreased by 0.40(<i>P</i><0.05). Corneal densitometry at 0-6 mm zone increased at 1mo and persisted 1a postoperatively(<i>P</i><0.05). The relationship of the increase in densitometric value and the decrease of thinnest pachymetry at 1a were in linear fashion. Index of surface variance, index of vertical asymmetry, keratoconus index, index of height decentration decreased at 1a(<i>P</i><0.05). Success rate at 1a was 90.24%. Postoperative corneal haze was found 11.35%, 30.27%, 15.67%, 10.27% and 2.16% at 1wk, 1, 3, 6mo and 1a respectively. No eyes developed corneal edema. There was one case of sterile keratitis.<p>CONCLUSION: Accelerated collagen cross-linking in keratoconus was effective to flatten, reshape the cornea, improved visual acuity, HOA and topometric indices. Great Kmax reduction was found in advanced keratoconus. The magnitude of Kmax reduction is also greatest among previous reports.
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@#AIM: To observe the changes of the vault height and the correlation analysis of visual quality under different pupil diameters after ICL surgery.<p>METHODS: Retrospective case study. Selected 43 patients(86 eyes)who implanted V4c ICL surgery successfully at Shanghai Aier Eye Hospital and followed up regularly to meet the measurement requirements from January 2018 to January 2019, Routine parameters and iTrace were checked before and 1wk, 1mo, and 3mo after surgery. Visante-OCT was used to measure the vault height under the pupils of 3mm and 5mm. <p>RESULTS: The vault height under the 3mm pupil at 1wk, 1mo and 3mo after surgery were(586.06±24.49, 560.16±21.31, 508.19±21.17)μm, the values under the 5mm pupil were(698.13±20.98, 667.69±20.16, 613.28±19.79)μm(<i>F</i><sub>Time</sub>=40.160,<i>P</i><sub>Time</sub><0.001; <i>F</i><sub>Groups</sub>=56.835,<i>P</i><sub>Groups</sub><0.001). The wave of vaule under the different pupils was(112.06±8.91, 107.53±6.94,101.01±10.64)μm(<i>F</i>=16.875, <i>P</i>>0.05). The total high-order aberration(HOA)and RMS of the whole eye after ICL were significantly reduced(<i>F</i>=29.847, 85.019; <i>P</i><0.001). The MTF and SR value were significantly higher than before surgery(<i>F</i>=47.653, 33.264; <i>P</i><0.001), and there was no statistical difference after ICL. At 3mo after surgery, the RMS and MTF values at 3mm and 5mm pupils were compared. The RMS value of the total HOA under the pupil of 5mm is significantly higher than that at 3mm, and the increase of spherical and trefoil aberration is significant(<i>t</i>=21.812, 17.136; <i>P</i><0.001). No significant difference in coma value(<i>t</i>=2.028, <i>P</i>>0.05). The MTF at 5mm pupils were significantly lower than those at 3mm at spatial frequencies of 5, 10, 15, 20, 25, 30c/d(<i>t</i>=15.138, 9.147, 7.018, 4.693, 3.814 and 3.075, all <i>P</i><0.05).<p>CONCLUSION: The impact of pupil movement on vault height fluctuation is about 110μm. It is recommended that the minimum vault height should be above 300μm. It can significantly reduce the root mean square value of total high-order aberration and aberration of the whole eye, and significantly increase the MTF and SR values after ICL surgery. The pupil size has a significant effect on visual quality after ICL. The spherical aberration and trefoil aberration increase under the condition of large pupil, and the MTF value generally decreases.
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@#The effectiveness, safety, stability and predictability ofsmall incision lenticule extraction(SMILE)have been proven by numerous studies. The postoperative visual quality has aroused more and more concern from the public. Recently, the influencing factors of visual quality after SMILE have been continuously reported, which offer further support for improving postoperative visual quality. This review mainly demonstrates the factors related to perioperative period that influence visual quality after SMILE performed on eyes of myopia or myopia astigmatism.
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@#AIM: To investigate the refractive outcomes and changes of corneal astigmatism and higher-order aberrations(HOAs)after Toric implantable Collamer lens implantation(Toric ICL).<p>METHODS: Prospective nonrandomized clinical trial studies. This study included 102 eyes of 57 patients underwent Toric ICL for myopic astigmatism correction. Uncorrected visual acuity(UCVA), manifest refraction, best spectacle-corrected visual acuity(BSCVA), manifest refractive cylinder, the corneal astigmatism and HOAs were measured preoperatively and up to 6mo after surgery. The vectors were measured using corneal topography, the Pentacam HR system and Wavefront analyzer.<p>RESULTS:Postoperative, the percentage of eyes had a spherical equivalent refraction within -1.00 D were 93.80%. The percentage of eyes within -0.50 D of emmetropia were 85.30%. The percentage of eyes which postoperative UCVA ≥20/25 was 66.30% and the percentage of eyes which postoperative UCVA ≥20/20 was 65.50%. The corneal astigmatism and aberrations preoperatively showed no statistical significance compared with postoperative. The total eyes aberrations and coma resulted in slight changes and had no statistically significant.<p>CONCLUSION:The corneal incision of Toric ICL implantation caused no changes in astigmatism and higher-order wavefront aberrations of cornea.
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@#AIM: To present the visual quality and refractive outcomes obtained in small incision lenticule extraction(SMILE)refractive surgeries, and observe the follow-up of patients over 1a period.<p>METHODS: Retrospective comparative analysis of 85 patients(85 eyes)were treated with SMILE between July and December 2019. Pre- and postoperative uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), spherical equivalent refraction(SE)were all observed, to evaluate the efficacy, safety and predictability after SMILE refractive surgery. Total corneal higher-order aberrations(HOAs), modulation transfer function cut-off(MTF<sub>cutoff</sub>), strehl ratio(SR), and objective scattering index(OSI)were evaluated. <p>RESULTS: One year after SMILE refractive surgery, the efficacy index was 1.08, 84 eyes(99%)reached an UDVA as or over CDVA preoperatively, 22 eyes(26%)gained one line of CDVA than preoperatively. The safety index was 1.04, 59 eyes(69%)of the treated eyes had an unchanged CDVA postoperatively, 24 eyes(28%)gained one line of CDVA, 2 eyes(2%)gained two lines of CDVA. 85 eyes(100%)were all within ±0.50D. The pre-correction is highly related with the actual correction of SE(<i>Y</i>=0.9949<i>X</i>-0.0033; <i>R</i><sup>2</sup>=0.9977). HOA, spherical aberration and coma were increased under pupil diameters of 6mm(all <i>P</i><0.001). Both MTF<sub>cutoff</sub> and SR were higher than that of SMILE preoperatively(<i>P</i><0.05).<p>CONCLUSION: SMILE demonstrated to be safe, effective, and predictable in the treatment of myopia and myopic astigmatism, and good accuracy in correcting medium and low astigmatism. The post-quality of retinal image is better than that of SMILE preoperatively.
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Objective To evaluate the relationship between the offset of a laser-assisted flap using the WaveLight FS200 femtosecond laser and the clinical results after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK).Methods In this prospective cohort study,125 patients who underwent FS-LASIK for myopia by WaveLight FS200 femtosecond laser from June 2017 to July 2018 at the Tungwah Ophthalmic Center were divided into two groups according to the offset of the corneal flap from the pupil center:the no-offset group (57 eyes) and the certain-offset group (68 eyes);the baseline data,including age,sex,uncorrected visual acuity (UCVA),spherical degree,and central corneal thickness were matched in the two groups.UCVA,residual astigmatism,spherical degree,corneal curvature and aberration were observed 1 week and 1 month after surgery.The study protocol was approved by the Ethics Committee of Tungwah Hospital of Sun Yat-Sen University (No.2017DHLL004).Written informed consent was obtained from each subject prior to entering the study cohort.Results UCVA,corneal curvature,spherical degree,spherical and corneal aberration between the two groups were not significantly different (all at P＞0.05).One week after surgery,the residual astigmatism was ≤-0.50 D in 50 eyes (87.7％,50/57) and ＞ -0.50 D in 7 eyes (12.3％,7/57) in the no-offset group;the residual astigmatism was ≤-0.50 D in 50 eyes (73.5％,50/68) and ＞-0.50 D in 18 eyes (26.5％,18/68) in the no-offset group.The residual astigmatism between the two groups 1 week after surgery was significantly different (x2 =3.902,P =0.048),and there was no significant difference in residual astigmatism 1 month after surgery (x2 =2.031,P =0.068).The trefoil of the no-offset group was statistically less than of the certain-offset group at 1 week and 1 month after surgery (0.05 [0.04,0.08] vs.0.06[0.04,0.10];0.05[0.03,0.07] vs.0.06[0.05,0.09]) (Z=-2.245,P--0.022;Z=-2.370,P=0.018).The spherical aberration and coma were not significantly different between the two groups at 1 week and 1 month after surgery (both at P＞0.05).Conclusions The offset from femtosecond laser-assisted flap by WaveLight FS200 has no effect on long-term visual acuity or residual astigmatism.Some patients may have different visual experiences because of the residual astigmatism and higher order aberration during the early postoperative stage.
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Objective@#To evaluate the relationship between the offset of a laser-assisted flap using the WaveLight FS200 femtosecond laser and the clinical results after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK).@*Methods@#In this prospective cohort study, 125 patients who underwent FS-LASIK for myopia by WaveLight FS200 femtosecond laser from June 2017 to July 2018 at the Tungwah Ophthalmic Center were divided into two groups according to the offset of the corneal flap from the pupil center: the no-offset group (57 eyes) and the certain-offset group (68 eyes); the baseline data, including age, sex, uncorrected visual acuity(UCVA), spherical degree, and central corneal thickness were matched in the two groups.UCVA, residual astigmatism, spherical degree, corneal curvature and aberration were observed 1 week and 1 month after surgery.The study protocol was approved by the Ethics Committee of Tungwah Hospital of Sun Yat-Sen University (No.2017DHLL004). Written informed consent was obtained from each subject prior to entering the study cohort.@*Results@#UCVA, corneal curvature, spherical degree, spherical and corneal aberration between the two groups were not significantly different (all at P>0.05). One week after surgery, the residual astigmatism was ≤-0.50 D in 50 eyes (87.7%, 50/57)and >-0.50 D in 7 eyes (12.3%, 7/57) in the no-offset group; the residual astigmatism was ≤-0.50 D in 50 eyes (73.5%, 50/68) and >-0.50 D in 18 eyes (26.5%, 18/68) in the no-offset group.The residual astigmatism between the two groups 1 week after surgery was significantly different (χ2=3.902, P=0.048), and there was no significant difference in residual astigmatism 1 month after surgery (χ2=2.031, P=0.068). The trefoil of the no-offset group was statistically less than of the certain-offset group at 1 week and 1 month after surgery (0.05[0.04, 0.08]vs.0.06[0.04, 0.10]; 0.05[0.03, 0.07]vs.0.06[0.05, 0.09])(Z=-2.245, P=0.022; Z=-2.370, P=0.018). The spherical aberration and coma were not significantly different between the two groups at 1 week and 1 month after surgery (both at P>0.05).@*Conclusions@#The offset from femtosecond laser-assisted flap by WaveLight FS200 has no effect on long-term visual acuity or residual astigmatism.Some patients may have different visual experiences because of the residual astigmatism and higher order aberration during the early postoperative stage.
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@#AIM: To observe the dry eye and high-order aberrations(HOAs)before and after laser <i>in situ</i> keratomileusis(LASIK)and to evaluate their effects on visual quality.<p>METHODS: Totally 58 myopia patients(116 eyes)were enrolled from June 2008 to June 2010, who were interviewed before and on 1a, 3a, 5a after operation. Their total HOAs, third-order coma, third-order trefoil and fourth-order spherical aberration of the corneal surface 0s and 10s after blinking were measured, and uncorrected visual acuity(UCVA), spherical equivalent(SE), corneal fluorescent staining, S I t were taken. OSDI questionnaire was scored, dry eye was diagnosed and graded. <p>RESULTS: Five years after LASIK, OSDI scores gradually increased from 10.003±1.462 to 20.252±2.540, BUT decreased from 8.402±2.640s to 6.897±3.408s and S I t decreased from preoperative level 14.382±6.241mm/5min, but recovered to preoperative level of 13.432±4.206mm/5min. The HOAs obtained 10s after blink were higher than 0s, and the augment of spherical aberration was the most significant. As to the same time point, the post operative HOAs were higher than that before operation, and the elevation of spherical aberration was still the most significant. 5a after operation, there was no difference between dry eye and non-dry eye patients on HOAs obtained 0s after blinking(all <i>P</i>>0.05). There was no significant difference between mild dry eye and preoperative HOAs 10s after blink 5a after operation(all <i>P</i>>0.05). However, the HOAs of moderate and severe dry eye patients were higher than non-dry eye patients(all <i>P</i><0.05). 5a after surgery, the HOAs differences between two time points of dry eye patients had positively correlated with OSDI scores. <p>CONCLUSION: The instability of tear film caused by dry eye in patients long-term after LASIK increases patient's HOAs and ultimately impair patient's visual quality, which mainly owe to the significant increase of spherical aberration.
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·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.
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AIM:To assess the changes in higher order aberrations after wavefront guided femtosecond laser assisted laser in situ keratomileusis ( FS-LASIK ) for moderate to high astigmatism.?METHODS: Eighty-eight eyes of 50 myopia patients with moderate to high astigmatism were included in this prospective study. There were 51 eyes with moderate astigmatism (≥-1. 50D and <-3. 00D) and 37 eyes with high astigmatism (≥-3. 00D). All patients underwent wavefront guided FS-LASIK. Uncorrected distance visual acuity ( UDVA ) , corrected distance visual acuity (CDVA), keratometry, central corneal thickness ( CCT)and higher order aberrations ( HOAs ) were evaluated before operation and 3mo postoperatively.?RESULTS:At the 3mo after operation, the mean UDVA of all eyes was above 20/20, better than before operation (P<0. 05), but CDVA remained unchanged (P=0. 36) and no eyes lost ≥2 lines of CDVA. Mean astigmstism of 85 eyes ( 97％) was reduced below - 1. 00D, mean astigmatism of 70 eyes ( 80％) was reduced below-0.50D(P<0. 05). The average corneal curvature was flatter by 3. 81 ± 1. 97D and CCT was reduced by 78. 66 ± 37. 22μm, postoperatively (P<0. 05). Coma and trefoil aberrations remained unchanged(P=0. 078, 0. 065). The spherical aberration, secondary astigmatism and the HOA root mean square ( RMS ) increased from 0. 19 ± 0. 06, 0.05±0. 02 and 0. 42±0. 12, preoperatively to 0. 32± 0. 17, 0. 26 ± 0. 08 and 0. 78 ± 0. 28 ( P < 0. 05 ), postoperatively.?CONCLUSION: Wavefront-guided FS-LASIK is a safe and effective option for the patients with moderate to high astigmstism although parts of HOAs increased.
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PURPOSE: The purpose of this study was to compare changes in higher-order aberrations after superior-incision cataract surgery between eyes with a within-the-rule (WTR) astigmatism and an against-the-rule (ATR) astigmatism in patients with positive vertical coma. METHODS: This study included patients who presented with positive vertical coma and who underwent cataract surgery through a 2.5 mm superior clear corneal incision. The eyes included in this study were divided into two groups (37 eyes with WTR astigmatism and 33 eyes with ATR astigmatism), and uncorrected visual acuity, best corrected visual acuity, and corneal astigmatism were measured before and after surgery. In addition, anterior, posterior, and total aberrations (i.e., oblique trefoil, horizontal trefoil, vertical coma, horizontal coma, spherical aberration, and total higher-order aberrations) were measured using a Pentacam. RESULTS: In the WTR astigmatism group, anterior/posterior corneal aberrations and total aberrations were significantly decreased after surgery (p < 0.05). However, in the ATR astigmatism group, a significant decrease in the posterior vertical coma (p = 0.008) was observed, although there was no change in total vertical coma. A significant increase in oblique trefoil was observed in both groups, while a significant decrease in horizontal trefoil was found in the ATR astigmatism group (all p < 0.05). For spherical aberration, the ATR astigmatism group showed a significant decrease in anterior cornea aberrations (p < 0.001). For total higher-order aberrations, the WTR astigmatism group showed a significant increase in anterior and posterior aberrations, while the ATR astigmatism group showed a significant increase in posterior aberrations (p < 0.05, p = 0.001, respectively). In the case of horizontal coma and corneal astigmatism, both groups exhibited no significant changes after surgery. CONCLUSIONS: When superior-incision cataract surgery was performed, vertical coma was affected by the axis of astigmatism, resulting in a significant decrease in the WTR astigmatism group. However, no significant changes in corneal astigmatism were observed before and after surgery.
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Humans , Astigmatism , Cataract , Coma , Cornea , Lotus , Visual AcuityABSTRACT
PURPOSE: To investigate the types of corneal higher-order aberration (HOA) induced by pterygium, residual corneal HOA after pterygium surgery, and correlations between corneal HOA and the length of the pterygium. METHODS: Fifty-three patients who underwent pterygium excision with conjunctival autograft were enrolled. Corneal HOA was measured by Pentacam® (Oculus Inc., Wetzlar, Germany) preoperatively and 3 months postoperatively in the 6-mm optical zone. Preoperative and postoperative HOAs of eyes with pterygium were compared with HOAs of the fellow eye to evaluate HOAs induced by pterygium and residual HOAs after pterygium surgery. Partial correlation analysis was performed to investigate the relationship between HOAs and the length of pterygium. A postoperative HOA less than 0.35 µm in size was defined as a favorable surgical outcome and the surgical indications were estimated using receiver operator characteristic (ROC) curve. RESULTS: Horizontal coma, root mean square (RMS) of coma, oblique trefoil, horizontal trefoil, RMS of trefoil, and total HOA were significantly greater in the eye with preoperative pterygium. Three months after pterygium excision, only RMS of coma and total HOA remained significantly greater in eyes with pterygium. Vertical coma, horizontal coma, RMS of coma, and oblique tetrafoil were correlated with pterygium length. Pterygium excision when pterygium length was less than 1.6 mm led to favorable surgical outcomes. CONCLUSION: Pterygium induced greater than third-order corneal HOAs and these HOAs were corrected via pterygium surgery. Longer pterygium length was associated with larger RMS of coma and larger coma RMS persisted after pterygium surgery. A pterygium length of 1.6 mm should be considered the cutoff for pterygium excision for reducing postoperative corneal HOA.
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Humans , Autografts , Coma , Lotus , PterygiumABSTRACT
Aim of study: The aim of this study is to assess wavefront aberration and contrast sensitivity (CS) after implantation of foldable iris claw – artiflex‑ and rigid iris claw – artisan‑ phakic intraocular lenses (pIOLs). Materials and Methods: A nonrandomized prospective comparative case study was performed on 57 eyes; of which, 54 were myopia and 3 were hyperopia. Twenty‑four patients had artisan pIOL implantation and 33 had artiflex pIOL implantation. Higher‑order aberration (HOA) and CS were obtained 1 year after surgery. Results: Total HOA in artisan group was greater than artiflex group (P = 0.044) with a mean HOA of 0.44 ± 0.15 root mean square (RMS) for artisan and 0.35 ± 0.15 RMS for artiflex. Although, there were no significant differences in the vertical trefoil, vertical coma, horizontal trefoil, horizontal coma, secondary astigmatism, quatrefoil, and fourth order spherical aberration in two groups. CS in mesopic conditions was better in artiflex‑treated eyes at three spatial frequencies of 6, 12, and 18 cycles per degree (cpd) (P = 0.003, P = 0.007, and P = 0.00, respectively), and no significant difference was seen between two lenses at 3 cpd. Conclusion: Although the components of HOA were not significantly different between two groups, total HOA was higher in artisan group, which may be due to the slight differences in each component, increasing the HOA as a total. CS was significantly better in artiflex group.
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PURPOSE: To analyze the changes of higher order aberration (HOA) measured serially by KR-1W(R) wavefront at every second for 10 seconds between, before, and after phacoemulsification and to evaluate the relationships between HOA and the ocular surface indicators (Schirmer test, tear break-up time, superficial punctate keratitis). METHODS: Corneal HOA was measured in 47 eyes of 30 patients pre- and postoperatively at 2, 4, 6, and 8 weeks by KR-1W(R) using the continuous measurement mode. The patients were divided into 2 groups according to their Schirmer test (above 10 mm or under 10 mm), tear break-up time (above 5 seconds or less than 5 seconds), and superficial punctate keratitis (any keratitis, none) for analysis of relationships between HOA and ocular surface indicators, and we also analyzed the correlation coefficient. RESULTS: Short-term follow up after phacoemulsification revealed that corneal HOA rapidly increased at 2 weeks and recovered to the preoperative level 8 weeks after surgery. Corneal HOA values showed increasing tendency depending on time at preop and 8 weeks after phacoemulsification, and the differences were statistically significant (preop: p < 0.001, 8 weeks: p = 0.027). There were no significant differences of HOA between the 2 groups divided according to their ocular surface indicators, and there were no significant correlations between HOA and ocular surface indicators at any time point. CONCLUSIONS: The HOA of the cornea was restored to its preoperative values at 8 weeks after surgery. Preoperative ocular surface indicators are not significantly influenced on postoperative corneal HOA. The surgical factors are more significant in postoperative corneal HOA than preoperative ocular surface indicators.
Subject(s)
Humans , Cornea , Follow-Up Studies , Keratitis , Phacoemulsification , TearsABSTRACT
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.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Amblyopia/complications , Anisometropia/complications , Cornea/pathology , Eyeglasses , Follow-Up Studies , Hyperopia/complications , Refraction, Ocular/physiology , Retrospective Studies , Treatment Outcome , Visual AcuityABSTRACT
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.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Amblyopia/complications , Anisometropia/complications , Cornea/pathology , Eyeglasses , Follow-Up Studies , Hyperopia/complications , Refraction, Ocular/physiology , Retrospective Studies , Treatment Outcome , Visual AcuityABSTRACT
PURPOSE: To evaluate the changes of higher order aberrations (HOAs) before and after laser subepithelial keratomileusis (LASEK) and to analyze the influence of tear film instability on HOAs of the corneal surface after LASEK. METHODS: In this cross-sectional study, 31 patients who underwent LASEK were divided into dry eye (16 patients, 32 eyes) and non-dry eye groups (15 patients, 30 eyes). Uncorrected distance visual acuity, spherical equivalent refraction, ablation depth, tear film parameters and Ocular Surface Disease Index (OSDI) questionnaire scores were evaluated in both groups. Total HOA root mean square (RMS), third-order coma, third-order trefoil and fourth-order spherical aberration (SA) of the corneal surface immediately and at 10 seconds after blinking were measured before and after surgery. RESULTS: The total HOA RMS, coma, trefoil and SA significantly increased after LASEK compared with preoperative values in both groups. In the dry eye group, total HOA RMS, coma and trefoil significantly increased except for SA at 10 seconds after blinking compared with those measured immediately after blinking. In addition, the changes of total HOA RMS, coma and trefoil were negatively correlated with tear film break-up time (R = -0.420, -0.473 and -0.439, respectively), but positively correlated with OSDI score (R = 0.433, 0.499 and 0.532, respectively). In the non-dry eye group, there were no significant differences between HOAs measured at 10 seconds after blinking and those measured immediately after blinking. CONCLUSIONS: The HOAs including coma, trefoil and SA significantly increased after LASEK. The tear film instability in the dry eye can be associated with more deterioration of the optical quality after LASEK, due to more significant increase of total HOA RMS, coma and trefoil.
Subject(s)
Adult , Female , Humans , Male , Young Adult , Cornea/physiopathology , Corneal Wavefront Aberration/etiology , Cross-Sectional Studies , Dry Eye Syndromes/physiopathology , Keratectomy, Subepithelial, Laser-Assisted/adverse effects , Lasers, Excimer/therapeutic use , Surveys and Questionnaires , Tears/physiology , Visual Acuity/physiologyABSTRACT
PURPOSE: To evaluate the visual outcome and optical quality in eyes with diffractive multifocal intraocular lens (DMIOL) implantation after myopic refractive surgery. METHODS: Nineteen eyes (15 patients) were implanted with AcriSof ReSTOR(R) SN6AD1, the aspheric DMIOL after myopic refractive surgery (laser-assisted in situ keratomileusis [LASIK] 14 eyes, photorefractive keratectomy [PRK] 4 eyes, laser-assisted subepithelial keratomileusis [LASEK] 1 eye). Preoperative and postoperative visual acuities and manifest refraction were measured. Preoperative corneal higher-order aberrations (HOAs) were measured using Hartmann-Shack (H-S) aberrometer in dilated pupils, and optical qualities were measured 1 month postoperatively using H-S aberrometer and a double-pass system under mesopic conditions. Patient satisfaction was investigated using a questionnaire at 2 months postoperatively. RESULTS: Uncorrected distant and near visual acuities at postoperative 2 months were 0.11 +/- 0.19, and 0.19 +/- 0.12 (log MAR), respectively. Postoperative spherical equivalent (SE) of 16 eyes (84.2%) was within +/-0.50 diopters (D) and all eyes were within +/-1.00 D from emmetropia. Preoperative corneal and postoperative ocular spherical aberrations in a 4.0 mm pupil diameter were 0.08 +/- 0.08 and 0.07 +/- 0.07 (microm), respectively. Objective scatter index was 3.42 +/- 1.71 and modulation transfer function (MTF) cut-off value was 21.03 +/- 12.37 cpd. General satisfaction score was 3.52 +/- 0.96 points out of 5, and 8 patients (11 eyes) were not satisfied with DMIOL implantation. CONCLUSIONS: After DMIOL implantation in the eyes with previous myopic refractive surgery, postoperative SE was close to the target D, but optical qualities and patient satisfaction were poor.