Corneal reshaping: an experiment with a type I collagen-based vitrigel for remodeling porcine corneas / Remodelamento corneano: relato de um experimento com um vitrigel a base de colágeno tipo I para remodelamento de córneas porcinas

ABSTRACT Purpose: This study aimed to report an experiment designed to determine anatomical changes in porcine corneas following placement of a novel polymer implant into the cornea. Methods: An ex vivo porcine eye model was used. A novel type I collagen-based vitrigel implant (6 mm in diameter) was shaped with an excimer laser on the posterior surface to create three planoconcave shapes. Implants were inserted into a manually dissected stromal pocket at a depth of approximately 200 μm. Three treatment groups were defined: group A (n=3), maximal ablation depth 70 μm; Group B (n=3), maximal ablation depth 64 μm; and group C (n=3), maximal ablation depth 104 μm, with a central hole. A control group (D, n=3) was included, in which a stromal pocket was created but biomaterial was not inserted. Eyes were evaluated by optical coherence tomography (OCT) and corneal tomography. Results: Corneal tomography showed a trend for a decreased mean keratometry in all four groups. Optical coherence tomography showed corneas with implants placed within the anterior stroma and visible flattening, whereas the corneas in the control group did not qualitatively change shape. Conclusions: The novel planoconcave biomaterial implant described herein could reshape the cornea in an ex vivo model, resulting in the flattening of the cornea. Further studies are needed using in vivo animal models to confirm such findings.

RESUMO Objetivo: Relatar um experimento projetado para determinar alterações anatômicas em córneas porcinas após a colocação de um novo implante de polímero na córnea. Métodos: Foi utilizado olho de porco ex vivo. Um novo agente modelador biocompatível, de colágeno tipo 1, com 6mm de diâmetro foi moldado com excimer laser em sua face posterior, para criar três formatos planocôncavos. Os implantes foram inseridos dentro de um bolsão, dissecado manualmente, a 200 micrômetros (μm). Foram definidos três grupos de tratamento: grupo A (n=3), teve a profundidade máxima de ablação de 70 μm; o grupo B (n=3), profundidade máxima de ablação de 64 μm; e o grupo C (n=3), profundidade máxima de ablação de 104 μm, com buraco central. O grupo controle, D (n=3), foi incluído, com a criação do bolsão estromal, porém sem inserir o material. A avaliação desses olhos foi realizada por tomografia de coerência óptica (OCT) e por tomografia corneana. Resultados: A tomografia corneana mostrou uma tendência para diminuição da ceratometria média em todos os 4 grupos. A tomografia de coerência óptica mostrou córneas com implantes localizados no estroma anterior e aplanamento visível, enquanto as córneas não mudaram qualitativamente o formato no grupo controle. Conclusões: O novo implante de biomaterial planocôncavo descrito aqui foi capaz de remodelar a córnea em modelo de animal ex vivo, resultando no aplanamento corneano. Novos estudos são necessários usando modelos animais in vivo para confirmar tais achados.

Effects of femtosecond laser assistcataract extraction on the levels of inflammatory factors in aqueous humor, corneal perception and high order aberration / 中国医师进修杂志

Objective:To investigate the effects of femtosecond laser assistcataract extraction on the levels of inflammatory factors in aqueous humor, corneal perception and high order aberration.Methods:Forty-eight patients (56 eyes) undergoing cataract surgery in the Shouguang People′s Hospital from June 2018 to February 2020 were enrolled in this study, and they were divided into observation group (24 patients and 27 eyes, femtosecond laser cataract phacoemulsification) and control group (24 patients and 29 eyes, coaxial microincision phacoemulsification) by random number table method. The levels of prostglndin E2 (PGE2), interleukin (IL)-6 and IL-1β in aqueous humor were detected before and after operation. Upper corneal and central corneal perception thresholds were recorded before surgery, 7 d after surgery, 1 month after surgery and 3 months after surgery. High order aberrations of the whole eye and cornea at 4mm pupil diameter before and after operation were recorded.Results:After operation, the levels of PGE2, IL-6 and IL-1β in aqueous humor in the observation group were lower than those in the control group: (45.62 ± 5.71) ng/L vs. (63.65 ± 5.62) ng/L, (15.25 ± 3.21) ng/L vs. (24.59 ± 6.13) ng/L, (17.16 ± 1.28) ng/L vs. (25.74 ± 4.62) ng/L, the differences were statistically significant ( P<0.05). The upper and central corneal perception threshold of observation group after operation for 7 d were higher than those in the control group: 4.55 ± 0.50 vs. 4.20 ± 0.33, 5.68 ± 0.49 vs. 5.52 ± 0.45, the differences were statistically significant ( P<0.05). The indexes of high order aberration of the whole eye decreased in the two groups ( P<0.05), while the indexes of cornea did not change significantly. The indexes of high order aberration of the whole eye and cornea between before and after surgery between the two groups had no significant differences ( P>0.05). Conclusions:Femtosecond laser assist cataractextraction can relieve inflammation, reduce the whole eye high order aberration, but not affect the cornea, and can improve corneal perception.

Comparison of corneal epithelial remodeling and corneal aberration changes after FS-LASIK and FS-LASIK Xtra / 中华实验眼科杂志

Objective:To investigate the status of corneal epithelial remodeling and changes in corneal aberration after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and FS-LASIK combined with corneal collagen cross-linking (FS-LASIK Xtra), and to analyze the relationship between corneal epithelial thickness (CET) and corneal aberration.Methods:A cohort study was conducted.A total of 172 patients (172 eyes) who underwent FS-LASIK at Yinhai Eye Hospital of Chengdu University of Traditional Chinese Medicine were enrolled from June 2021 to February 2022.The 172 eyes were divided into FS-LASIK group (94 eyes) and FS-LASIK Xtra group (78 eyes) according to the surgical procedure, with a total follow-up of 6 months.The cornea was divided into a central 2-mm ring and a ring of 2-5 mm centered on the central cornea.CET at 9 regions in the central 0-5 mm area was measured by OCT before and at 1, 3 and 6 months after surgery, and the corneal higher-order aberration (HOA) was measured by the iTrace visual function analyzer.The main outcomes were the increase in CET (ΔCET), and corneal HOA at 6 months after surgery.The relationship between central corneal ΔCET and corneal aberration was analyzed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Yinhai Eye Hospital of Chengdu University of Traditional Chinese Medicine (No.2021yh-009). Written informed consent was obtained from each subject.Results:At 1, 3 and 6 months after surgery, the central, superior, superior nasal, nasal, inferior nasal, inferior, inferior temporal, temporal and superior temporal ΔCET were significantly smaller in FS-LASIK Xtra group than in FS-LASIK group (all at P<0.05). In FS-LASIK Xtra group, 6-month postoperative central, superior, superior nasal, inferior and inferior temporal ΔCET were significantly larger than those at 1 month after surgery, and 3- and 6-month postoperative temporal ΔCET were significantly larger than that at 1 month after surgery, and 6-month postoperative superior temporal ΔCET was significantly larger than those at 1 and 3 months after surgery (all at P<0.05). In FS-LASIK group, 3- and 6-month postoperative central, superior, inferior and inferior temporal ΔCET were significantly larger than those at 1 month after surgery, and 6-month postoperative superior nasal ΔCET was significantly larger than that at 3 months after surgery, and 6-month postoperative nasal, inferior nasal, temporal, superior temporal ΔCET were significantly larger than those at 1 and 3 months after surgery (all at P<0.05). There was no significant difference in vertical trefoil, vertical and horizontal coma changes at different time points after surgery between both groups (vertical trefoil: χ2group=4.27, P=0.118; χ2time=0.01, P>0.05.vertical coma: χ2group=5.74, P=0.057; χ2time=0.08, P=0.957.horizontal coma: χ2group=3.97, P=0.137; χ2time=0.51, P=0.773). The tilted trefoil changes at 1, 3 and 6 months after surgery of FS-LASIK Xtra group were significantly larger than those of FS-LASIK group (all at P<0.05). The 6-month spherical aberration change in FS-LASIK Xtra group was significantly higher than that at 1 month after surgery, and the 6-month spherical aberration change in FS-LASIK group was significantly higher than that at 1 and 3 months after surgery (all at P<0.05). The 6-month total HOA change in FS-LASIK group was significantly lower than that at 1 and 3 months after surgery (all at P<0.05). In FS-LASIK group, central corneal ΔCET was weakly positively correlated with spherical aberration at 1 and 6 months after surgery ( rs=0.257, P=0.008; rs=0.244, P=0.012), and was weakly positively correlated with total HOA ( rs=0.253, P=0.009; rs=0.279, P=0.004). Conclusions:The postoperative ΔCET after FS-LASIK Xtra is smaller than that after FS-LASIK, but the homogeneity of ΔCET in each region is similar between the two groups.The changes in corneal HOA after surgery are similar in both groups, and there is a certain association between the overall epithelial distribution and corneal aberration.

Comparison of early postoperative visual quality between SMILE and SPT-TransPRK / 中华实验眼科杂志

Objective:To investigate the differences and changes in early postoperative visual quality after small incision lenticule extraction (SMILE) and smart pulse technology-assisted transepithelial photorefractive keratectomy (SPT-TransPRK).Methods:A cohort study was performed.A total of 92 patients (92 eyes) who underwent corneal laser refractive surgery were enrolled in Dalian Third People's Hospital Affiliated to Dalian Medical University from February 2021 to May 2021.The data from the right eye were collected for analysis.The patients were divided into SMILE group (40 patients, 40 eyes) and SPT-TransPRK group (52 patients, 52 eyes). Preoperative, 1- and 3-month postoperative visual acuity were measured to calculate the effectiveness, which was defined as the ratio of postoperative uncorrected visual acuity (UCVA) to preoperative best corrected visual acuity.Refraction was measured by an AR-1 autorefractor.Corneal higher-order aberration (HOA) including total HOA, spherical aberration and coma was measured by Sirius corneal topographer.Objective scatter index (OSI), modulation transfer function cut-off frequency (MTF cut-off), Strehl ratio (SR), simulated contrast visual acuity VA100 (day), VA20 (dusk) and VA9 (night) were measured via OQAS II visual quality analysis system.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the Dalian Third People's Hospital Affiliated to Dalian Medical University (No.2019-KT-010). Written informed consent was obtained from each subject.Results:There was no significant difference in 3-month postoperative UCVA and effectiveness between the two groups ( Z=0.880, P=0.380; t=0.920, P=0.058). Patients in SPT-TransPRK group showed mild hyperopia 3 months after surgery.Preoperative, 1- and 3-month postoperative total corneal HOA was (0.47±0.18), (0.70±0.22) and (0.74±0.19)μm in SMILE group, and (0.40±0.14), (0.98±0.35) and (0.94±0.22)μm in SPT-TransPRK group respectively, showing statistically significant differences ( Fgroup=13.851, P=0.001; Ftime=29.960, P<0.001). Preoperative, 1- and 3-month postoperative spherical aberration was (-0.20±0.09), (-0.44±0.14) and (-0.44±0.15)μm in SMILE group, and (-0.20±0.10), (-0.71±0.23) and (-0.75±0.20)μm in SPT-TransPRK group respectively, showing statistically significant differences ( Fgroup=31.037, P<0.001; Ftime=48.005, P<0.001). The postoperative total corneal HOA and spherical aberration were increased in both groups compared with before surgery, with statistically significant differences (all at P<0.05). The 1- and 3-month postoperative total corneal HOA and spherical aberrations were smaller in SMILE group than in SPT-TransPRK group, and the differences were statistically significant (all at P<0.05). The 1- and 3-month postoperative coma were increased in both groups compared with before surgery, showing statistically significant differences (all at P<0.05). In SMILE group, 1-month postoperative OSI was higher and 1-month postoperative MTF cut-off, SR, and VA9 were lower than those before surgery, and 3-month postoperative OSI was higher and 3-month postoperative SR and VA9 were lower than those before surgery, showing statistically significant differences (all at P<0.05). In SPT-TransPRK group, 1-month postoperative OSI was higher and 1-month postoperative MTF cut-off, SR, VA100, VA20, and VA9 were lower than those before surgery, showing statistically significant differences (all at P<0.05). There was no significant difference in OSI, MTF cut-off, SR, VA100, VA20, and VA9 between 3 months postoperatively and before surgery in the SPT-TransPRK group (all at P>0.05). There was no significant difference in coma, OSI, MTF cut-off, SR, VA100, VA20, and VA9 between two groups (all at P>0.05). Conclusions:Both SMILE and SPT-TransPRK are effective methods for correcting myopia and they have comparable visual quality.Compared with SPT-TransPRK, corneal total HOA and spherical aberration are smaller after SMILE.

Application of spherical lens with 0.05 D intervals in optometry for small incision lenticule extraction in myopic eyes / 中华实验眼科杂志

Objective:To investigate the clinical value of spherical lens with 0.05 D intervals in optometry for small incision lenticule extraction (SMILE) in myopic eyes.Methods:A randomized controlled clinical study was conducted.Sixty patients (120 eyes) with low to moderate myopia and myopic astigmatism who underwent SMILE in the 989th Hospital of the PLA from June 2021 to February 2022 were enrolled.The patients were randomly divided into 0.05 D interval group (optometry with spherical lens at 0.05 D interval) and 0.25 D interval group (optometry with spherical lens at 0.25 D interval), with 30 cases (60 eyes) in each group.There was no significant difference in matched age, sphericity, cylindricity, and best corrected visual acuity (BCVA) (all at P>0.05). The preoperative monocular red-green balance, 1- and 3-month postoperative monocular red-green balance, uncorrected visual acuity and spherical equivalent of both groups were compared.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the 989th Hospital of the PLA (No.WZLL-2021-034). Written informed consent was obtained from each subject before any medical examination. Results:The preoperative red-green balance rate in 0.05 D interval group was 95.00%(57/60), which was higher than 35.00%(21/60) in 0.25 D interval group, showing a statistically significant difference ( Wald χ2=17.642, P<0.001). The 1- and 3-month postoperative red-green balance rates in 0.05 D interval group were 63.33%(38/60) and 56.67%(34/60), which were higher than 23.33%(14/60) and 21.67%(13/60) in 0.25 D interval group respectively, showing statistically significant differences ( Wald χ2=9.137, P=0.003; Wald χ2=7.483, P=0.006). The 1- and 3-month postoperative visual acuity in 0.05 D interval group were -0.1(-0.1, -0.1) and -0.1(-0.1, -0.1), which were higher than 0.0(-0.1, 0.0) and -0.1(-0.1, 0.0) in 0.25 D interval group respectively, showing statistically significant differences ( Wald χ2=11.624, P=0.001; Wald χ2=12.841, P<0.001). The 1- and 3-month postoperative spherical equivalent were -0.07(-0.25, 0.13)D and -0.13(-0.25, 0.13)D in 0.05 D interval group, which were higher than -0.13(-0.38, 0.25)D and -0.13(-0.38, 0.25)D in 0.25 D interval group respectively, showing no statistically significant difference between the two groups ( Wald χ2=0.029, P=0.866; Wald χ2=0.189, P=0.664). Conclusions:Compared with spherical lens at 0.25 D interval, 0.05 D interval can improve the accuracy of preoperative and postoperative red-green balance rate and postoperative visual acuity in patients with low to moderate myopia who undergo SMILE.

Comparison of corneal higher order aberration after femtosecond laser-assisted laser in situ keratomileusis and small incision lenticule extraction / 中华实验眼科杂志

Objective:To analyze and compare the corneal higher order aberration (HOA) after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE).Methods:A non-randomized controlled study was conducted.Sixty myopic patients (60 eyes) who underwent FS-LASIK or SMILE correction at Shandong Eye Hospital from April 2018 to January 2020 were enrolled and the data from the right eye were collected for analysis.Thirty cases (30 eyes) who received FS-LASIK in FS-LASIK group and 30 cases (30 eyes) who received SMILE in SMILE group had a preoperative equivalent spherical diopter of (-5.36±1.11)D and (-4.93±1.03)D, respectively.The HOA of the 6-mm anterior surface, posterior surface, and whole cornea were measured before surgery and at 1, 3, 6, and 12 months after surgery using Pentacam.The root mean square values (μm) of total corneal HOA, spherical aberration, coma and trefoil were obtained.Differences in the above root mean square values at different time points were compared between the two groups.The study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Shandong Eye Hospital (No.SDSYKYY20180306). Written informed consent was obtained from each subject.Results:The preoperative and 1-, 3-, 6-, 12-month postoperative total HOA of the anterior corneal surface were (0.428±0.126), (0.775±0.169), (0.811±0.194), (0.759±0.214), (0.704±0.199)μm in the FS-LASIK group and (0.409±0.094), (0.656±0.148), (0.681±0.161), (0.668±0.175), (0.648±0.160)μm in the SMILE group, with a significant overall difference ( Fgroup=5.652, P=0.024; Ftime=107.169, P<0.01). Compared with SMILE group, the postoperative total HOA of anterior corneal surface and spherical aberration at different time points were increased in FS-LASIK group, showing statistically significant differences (all at P<0.05). Compared with before surgery, the postoperative total HOA of the anterior corneal surface and spherical aberration at different time points were increased in both groups, showing statistically significant differences (all at P<0.05). In the two groups, the 6- and 12-month postoperative total HOA of the anterior corneal surface were reduced in comparison with the 3-month postoperative ones of the anterior corneal surface, and the 12-month postoperative spherical aberrations of the anterior corneal surface were significantly reduced in comparison with the 1- and 3-month postoperative ones of the anterior corneal surface, showing statistically significant differences (all at P<0.05). There were significant differences in the coma and trefoil of the anterior corneal surface between before and after the operation (coma: Ftime=47.848, P<0.01; trefoil: Ftime=2.497, P=0.046). Compared with before surgery, the postoperative coma was significantly increased in the two groups (all at P<0.05). There were significant differences in total corneal HOA and spherical aberration at different postoperative time points between the two groups (total HOA: Fgroup=8.093, P=0.008; Ftime=125.019, P<0.01.spherical aberration: Fgroup=4.771, P=0.037; Ftime=34.033, P<0.01). Compared with SMILE group, the total corneal HOA and spherical aberration were significantly increased in FS-LASIK group at different postoperative time points (all at P<0.05). Compared with before surgery, postoperative total HOA of the anterior corneal surface and spherical aberration at different postoperative time points were significantly increased in both groups (all at P<0.05). In both groups, the 12-month postoperative corneal spherical aberration was significantly reduced in comparison with the 1- and 3-month postoperative ones (all at P<0.05). There was a significant difference in coma between before and after surgery ( Ftime=30.829, P<0.01). Compared with before surgery, the postoperative coma was significantly increased at different time points in both groups (all at P<0.05). Conclusions:Both FS-LASIK and SMILE increase the HOA of the anterior corneal surface and the whole cornea.Compared with FS-LASIK, SMILE introduces less HOA of the anterior corneal surface and the whole cornea as well as spherical aberrations.

Application of nomogram in corneal refractive surgery / 中华实验眼科杂志

Corneal refractive surgery is widely used to correct myopia and astigmatism because of its safety, effectiveness and stability.Precision medicine is the future direction of development, and the demands for accuracy in corneal refractive surgery are also increasing, which has a direct impact on patient satisfaction.Nomogram, as a key design in refractive surgery, needs to be combined with several important predictors to quantify individual risk.Different surgical methods need different nomograms.In this paper, the effects of corneal surface surgery, lamellar surgery, modeling algorithm and possible factors such as patient's sex, age, expected correction, corneal curvature, preoperative spherical equivalent, etc.on the predicted values were discussed.At the same time, the application of nomograms in corneal refractive surgery at home and abroad in recent years and the research progress of nomogram influencing factors were explored, in order to provide more and more accurate reference for clinical practice, to improve the accuracy of corneal refractive surgery and help patients achieve satisfactory postoperative visual quality.

Avaliação do conhecimento sobre cirurgia refrativa por meio de questionário eletrônico / Evaluation of knowledge in refractive surgery using an on-line questionnaire

RESUMO Objetivo: Desenvolver e aplicar um questionário eletrônico para avaliação do conhecimento em cirurgia refrativa na população analisada. Métodos: Foi aplicado um questionário eletrônico a uma população composta de 840 participantes voluntários maiores de 18 anos. Resultados: A média da idade dos participantes foi 37,85 anos, sendo 60,1% do feminino. Dentre os participantes, 20,95% reportaram ter sido submetidos a alguma cirurgia ocular prévia, sendo 73,86% com objetivo refrativo. Entre estes, 73,08% mostraram-se satisfeitos/muito satisfeitos com o resultado. O critério mais importante na escolha de um cirurgião refrativo foi a indicação por um conhecido que realizara a cirurgia (43,81%). Destaca-se que os participantes submetidos à cirurgia refrativa discordaram que "a cirurgia é um procedimento simples e isento de riscos" mais do que as demais pessoas (p=0,0045) e também que "o objetivo principal da cirurgia é 'zerar' o grau" (p=0,0252). Conclusão: Nota-se a necessidade de melhorar o conhecimento pré-operatório da população sobre cirurgia refrativa e também de educação continuada para os oftalmologistas. Este estudo fomenta o desenvolvimento de novas ferramentas de educação com informações claras e de fácil acesso, que tenham caráter informativo, e não de convencimento.

ABSTRACT Objective: The purpose of this study was to develop and apply an online questionnaire to assess knowledge in Refractive Surgery in the analyzed population. Methods: An online questionnaire was applied to a population composed of 840 volunteer participants over 18 years of age. Results: The mean age of population was 37.85 years, of whom 60.1% were female. 20.95% of the participants reported having undergone previous eye surgery, 73.86% of which had a refractive objective. Among these, 73.08% were satisfied / very satisfied with the result. The most important criterion when choosing a refractive surgeon was the indication by a friend who underwent the procedure (43.81%). It is noteworthy that the participants who underwent refractive surgery disagreed more than the other people that "the surgery is a simple and risk-free procedure" (p = 0.0045) and that "the main objective of the surgery is to "zero" the diopter" (p = 0.0252). Conclusion: It is essential to improve population's preoperative knowledge about Refractive Surgery, as well as continuing education for ophthalmologists. Therefore, this study encourages the development of new education tools with clear and easily accessible information, which should be informative, and not convincing.

Influence and significance of angle Kappa on total ocular aberrations before and after SMILE surgery / 中华实验眼科杂志

Objective:To investigate the influence of angle Kappa on total high-order aberration (HOA) before and after small incision lenticule extraction (SMILE).Methods:An observational case series study was conducted.Right eyes of 98 patients with myopia and myopic astigmatism who underwent SMILE surgery at Tianjin Eye Hospital from April 2015 to May 2016 were selected.Uncorrected visual acuity (UCVA), spherical diopter and cylindrical diopter under cycloplegic condition were examined before the surgery and at l and 3 months postoperatively.The chord distance of angle Kappa was measured by Pentacam topography.Wavefront aberrations were measured by WaveScan aberrometer.Pre- and postoperative UCVA, refractive status and each HOA were analyzed.The relationship between angle Kappa and each HOA was analyzed by Pearson correlation.This study adhered to the Declaration of Helsinki.The study protocol was approved by an Ethics Committee of Tianjin Eye Hospital (No.TJYYLL-2017-17). Written informed consent was obtained from each subject.Results:The preoperative, postoperative 1-month and postoperative 3-month UCVA (LogMAR) were 0.06±0.23, -0.03±0.07 and -0.05±0.07, respectively, showing a statistically significant difference ( F=779.330, P<0.001). There were statistically significant differences in spherical diopter, cylinder diopter and spherical equivalent (SE) between before and after operation ( F=1 107.811, 127.786, 1 191.266; all at P<0.001), and the postoperative spherical diopter, cylinder diopter and SE were significantly lower than those before surgery (all at P<0.001). At 6-mm pupil diameter, significant differences were found between postoperative total HOA, spherical aberration, coma, the third-order aberration (S3), fourth-order aberration (S4), fifth-order aberration (S5) and sixth-order aberration (S6) and the preoperative values ( F=75.915, 78.231, 66.186, 64.521, 97.161, 36.623, 28.852; all at P<0.001). The postoperative 1- and 3-month total HOA, spherical aberration, coma, S3, S4, S5 and S6 were significantly increased in comparison with those before surgery (all at P<0.05). There was a positive correlation between angle Kappa and total HOA, coma and S3 at 1 and 3 months after surgery (total HOA: r=0.357, 0.363; both at P<0.001.coma: r=0.310, 0.341; both at P<0.01.S3∶ r=0.343, 0.371; both at P<0.01). Significant differences were found in preoperative, postoperative 1-month and 3-month total HOA, coma and S3 between groups with different angle Kappa ( Fgroup=3.363, 4.277, 4.029; all at P<0.05). The postoperative total HOA, coma and S3 of the larger angle Kappa group were greater than those of the smaller angle Kappa group, with statistically significant differences between them (all at P<0.05). Conclusions:A larger angle Kappa may induce HOAs in SMILE surgery.

Comparison of the preservation effect of DX solution and glycerin preservation solution on corneal stromal lens / 中华实验眼科杂志

Objective:To compare the preservation effect of DX preservation solution and glycerin preservation solution on the corneal stromal lens.Methods:Sixty intact corneal stromal lens samples were collected during femtosecond small incision lenticule extraction (SMILE) from 60 myopic eyes of 30 subjects at Qingdao Eye Hospital of Shandong First Medical University from February 2019 to May 2019.The samples were randomized into DX preserved 1-day group, DX preserved 1-week group, glycerin preserved 1-day group, glycerin preserved 1-week group and glycerin preserved 2-week group according to the different preservation methods, with 10 samples in each group.No intervention was done in the samples of the normal control group.Trypan blue staining was used to count the number of dead cells in the corneal stromal lens.The morphological structure of the corneal stromal lens was examined with an optical microscope, and its ultrastructure was observed under the transmission electron microscope.This study adhered to the Declaration of Helsinki.Written informed consent was obtained from each patient prior to any medical intervention.The study protocol was approved by an Ethics Committee of Qingdao Eye Hospital of Shandong First Medical University (No.2019-30).Results:The number of dead cells was (53.1±14.2), (50.8±9.8), (70.4±13.6) and (172.8±31.7) and (182.8±14.2) cells/field in the DX preserved 1-day group, DX preserved 1-week group, glycerin preserved 1-day group, glycerin preserved 1-week group and glycerin preserved 2-week group, respectively, showing a significant difference among the five groups ( F=16.37, P<0.05). There was no significant difference between the DX preserved 1-day group and 1-week group ( P>0.05). The number of dead cells was significantly less in the glycerin preserved 1-day group than that of the glycerin preserved 1-week group and glycerin preserved 2-week group, and the number of dead cells was significantly increased in the glycerin preserved 1-week group compared with the DX preserved 1-week group (all at P<0.05). The arrangement of collagen fibers of the corneal stromal lens was regular and the cells were intact in the normal control group, DX preserved 1-day group and DX preserved 1-week group.The tissue edema, bare cell nuclei and loose collagen fibers were found in the samples in the glycerin preserved 1-day group.The corneal stromal lens was compact and the collagen fibers were dense and the nuclei were intact in the DX preserved 1-day group and DX preserved 1-week group.The distribution of the cells was sparse and the cell structure was abnormal under the transmission electron microscope in various glycerin preserved groups. Conclusions:The structure of corneal stromal lens can be well preserved for one week by DX storage solution.The preservation effect of DX solution is better for fresh human corneal stromal lens than glycerin solution.

Treatment strategy for bilateral severe subepithelial fibrosis after photorefractive keratectomy enhancement / Estratégia de tratamento para fibrose subepitelial grave bilateral após aprimoramento com ceratectomia fotorrefrativa

ABSTRACT A 27-year-old healthy man with a history of bilateral photorefractive keratectomy (PRK) enhancement after femtosecond laser in situ keratomileusis (LASIK) presented with decreased uncorrected distance visual acuity (UDVA) of 20/125 in the right eye (OD) and 20/300 in the left eye (OS) six months after PRK. Examination revealed bilateral dense subepithelial opacities. Both eyes (OU) were treated with superficial keratectomy combined with phototherapeutic keratectomy (PTK) and adjunctive application of mitomycin C 0.02%. At three months follow up UDVA was 20/30 OD and 20/25 OS. Superficial keratectomy combined with PTK seems to be a safe and efficient technique for treatment of dense subepithelial scar formation following PRK enhancement after LASIK.

RESUMO Um homem saudável de 27 anos de idade com história de aprimoramento com ceratectomia fotorrefrativa (PRK) bilateral, após Ceratomileuse Assistida por Excimer Laser In Situ (LASIK) com laser de femtossegundos, apresentou diminuição da acuidade visual à distância não corrigida (AVNC) de 20/125 no olho direito (OD) e 20/300 no olho esquerdo (OE) seis meses após PRK. O exame revelou opacidades subepiteliais densas bilaterais. Ambos os olhos (AO) foram tratados com queratectomia superficial combinada com ceratectomia fototerapêutica (PTK) e aplicação adjuvante de mitomicina C a 0,02%. Aos três meses de acompanhamento, o AVNC foi de 20/30 OD e 20/25 OE. A ceratectomia superficial combinada com PTK parece ser uma técnica segura e eficiente para o tratamento da formação densa de cicatrizes subepiteliais após o aprimoramento com PRK pós-LASIK.

Intraoperative complications and treatment in femtosecond laser small incision lenticule extraction / 中华实验眼科杂志

As a relatively new procedure, femtosecond laser small incision lenticule extraction (SMIIE) is still in its initial stage.Despite the safety, efficacy, predictability and stability it has showed in refractive error correction, there are still reports of intraoperative complications resulting in different clinical outcomes in SMILE.SMILE includes the production of lenticule by femtosecond laser, the separation and extraction of lenticule, and intraoperative complications may occur in every step.The production of the lenticule is completely dependent on the femtosecond laser, so complications related to femtosecond lasers are inevitable, such as suction loss, opaque bubble layer and black spots.Separation and extraction of the lenticule relies on the experience and surgical skills of surgeon, during which, torn corneal cap, difficult lenticule extraction, lenticule remnants, bleeding and lenticule decentration may occur.In this article, the categories, reasons, management and effects of intraoperative complications on outcome in SMILE were summarized to improve the ability of ophthalmologists to handle intraoperative incidents and enhance surgical safety.

Femtosecond laser-assisted anterior lamellar keratoplasty with suboptimal outcomes: a case series / Ceratoplastia lamelar anterior assistida por laser de femtosegundo com resultados subótimos: uma série de casos

ABSTRACT Objective To identify preoperative clinical characteristics of patients undergoing femtosecond laser-assisted anterior lamellar keratoplasty who failed to achieve optimal postoperative visual outcomes. Methods In this single-center, retrospective case series, patients who underwent femtosecond laser-assisted anterior lamellar keratoplasty between 2013 and 2018 were included if they required graft revision, subsequent corneal procedure, or additional postoperative visits for a femtosecond laser-assisted anterior lamellar keratoplasty-related issue. Visual outcomes assessed included best-corrected visual acuities and postoperative corneal astigmatism. Results Eight eyes of eight patients meeting the above criteria were included. Mean patient age was 64.5 years (range, 21 to 89 years). Mean included preoperative best-corrected visual acuities was one logarithm of the minimum angle of resolution (range, 0.3 logarithm of the minimum angle of resolution to counting fingers). Indications for femtosecond laser-assisted anterior lamellar keratoplasty included anterior stromal scarring due to viral keratitis (two cases), bacterial keratitis (one case), chronic epithelial defect (one case), Avellino dystrophy (one case), trauma (one case), and chronic endothelial failure (two cases). Six patients had history of prior intraocular surgeries including phacoemulsification (four cases), pars plana vitrectomy (one case), endothelial keratoplasty (two cases), and trabeculectomy (one case). Mean included best-corrected visual acuities at most recent follow-up was one logarithm of the minimum angle of resolution (range zero logarithm of the minimum angle of resolution to hand movements) representing improvement or stability in six of eight patients. Visually significant corneal astigmatism was present in four of eight patients. Post-femtosecond laser-assisted anterior lamellar keratoplasty procedures included graft repositioning, arcuate keratotomy, phacoemulsification, and regraft. Conclusion While femtosecond laser-assisted anterior lamellar keratoplasty offers a less-invasive treatment option compared to penetrating keratoplasty, intraoperative and postoperative management can be complex. Femtosecond laser-assisted anterior lamellar keratoplasty in patients with history of prior endothelial keratoplasty or ongoing ocular comorbidities should be pursued with caution.

RESUMO Objetivo Identificar as características clínicas pré-operatórias de pacientes submetidos à ceratoplastia lamelar anterior assistida por laser de femtossegundo que não alcançaram resultados visuais pós-operatórios ideais. Métodos Nesta série de casos retrospectiva em um único centro, os pacientes submetidos à ceratoplastia lamelar anterior assistida por laser de femtossegundo entre 2013 e 2018 foram incluídos se precisassem de revisão do enxerto, procedimento corneano subsequente ou visitas pós-operatórias adicionais por uma intercorrência relacionada à ceratoplastia lamelar anterior assistida por laser de femtossegundo. Os resultados visuais avaliados incluíram melhor acuidade visual corrigida e astigmatismo pós-operatório da córnea. Resultados Oito olhos de oito pacientes que atenderam aos critérios descritos foram incluídos. A idade média dos pacientes foi de 64,5 anos (variação de 21 a 89). A melhor acuidade visual corrigida pré-operatória média foi de um logaritmo do mínimo ângulo de resolução (variação de 0,3 logaritmo do mínimo ângulo de resolução para contagem de dedos). As indicações para ceratoplastia lamelar anterior assistida por laser de femtossegundo incluíram cicatriz do estroma anterior devido à ceratite viral (dois casos), ceratite bacteriana (um caso), defeito epitelial crônico (um caso), distrofia de Avellino (um caso), trauma (um caso) e insuficiência endotelial crônica (dois casos). Seis pacientes tinham história de cirurgias intraoculares anteriores, incluindo facoemulsificação (quatro casos), vitrectomia via pars plana (um caso), ceratoplastia endotelial (dois casos) e trabeculectomia (um caso). O mínimo ângulo de resolução médio no acompanhamento mais recente foi de um logaritmo do mínimo ângulo de resolução (variação de zero logaritmo do mínimo ângulo de resolução para movimentos das mãos), representando melhora ou estabilidade em seis de oito pacientes. Astigmatismo corneano visualmente significativo estava presente em quatro de oito pacientes. Os procedimentos pós-ceratoplastia lamelar anterior assistida por laser de femtossegundo incluíram reposicionamento do enxerto, ceratotomia arqueada, facoemulsificação e enxerto. Conclusão Embora a ceratoplastia lamelar anterior assistida por laser de femtossegundo ofereça uma opção de tratamento menos invasiva em comparação com a ceratoplastia penetrante, o manejo intra e pós-operatório pode ser complexo. A ceratoplastia lamelar anterior assistida por laser de femtossegundo em pacientes com história de ceratoplastia endotelial anterior ou comorbidades oculares correntes deve ser avaliada com cautela.

Depósitos corneales producidos probablemente por ciprofloxacino tópico luego de entrecruzamiento o Cross-Linking corneal / Corneal deposits likely caused by topical ciprofloxacin after corneal cross-linking

Resumen Hay medicamentos de uso tópico ocular como las fluoroquinolonas, que cuando son utilizadas en forma aislada o asociadas a otros fármacos pueden producir depósitos corneales en pacientes posoperados durante el período de desepitelización corneal. Presentamos el primer caso nacional reportado de una paciente con queratocono que presentó depósitos corneales luego de realizarse entrecruzamiento del colágeno corneal (CXL) probablemente debido al uso de ciprofloxacino y su evolución.

Summary There are ocular topical medicines like ciprofloxacin that when used alone or in combination can deposit on the cornea after surgical procedures during the period of cornel de-epithelization. We present here the first case reported in the country of a patient with keratoconus who presented corneal deposits after undergoing corneal cross-linking likely due to the use of topical ciprofloxacin.

Refractive and visual outcomes after Ferrara corneal ring segment implantation at a 60% depth in keratoconic eyes: case series / Resultados refrativos e visuais após a inserção do anel de Ferrara a uma profundidade de 60% em olhos com ceratocone: série de casos

ABSTRACT Purpose: This report addresses refractive, topographic, visual acuity, and optical coherence tomography outcomes 12 months after femtosecond, laser-assisted insertion of Ferrara intrastromal corneal ring segments in keratoconic eyes at a depth of 60%. Methods: Interventional, prospective, non-comparative case series. We performed femtosecond, laser-assisted insertion of Ferrara intrastromal corneal ring segments in 15 keratoconic eyes. We included patients with documented keratoconus who voluntarily signed informed consents if they had best spectacle-corrected visual acuity ≥0.30 logMAR and corneal thickness ≥400 μm. We excluded patients with previous ocular surgery or corneal curvatures >65 diopters (D). Our main outcome measures were best spectacle-corrected visual acuity and corneal topographic parameters (flattest, steepest and average keratometry [K]), evaluated at baseline and at 1-,3-,6-, and 12-month follow-ups. Results: The mean ± standard deviation baseline uncorrected visual acuity and best spectacle-corrected visual acuity were 1.03 ± 0.46 and 0.42 ± 0.13, respectively; the 12-month mean standard deviation uncorrected visual acuity and best spectacle-corrected visual acuity were 0.72 ± 0.37 and 0.31 ± 0.16, respectively, without significant differences (p=0.05 for both). The mean best spectacle-corrected visual acuity improvements were statistically significant after 3- (p=0.02) and after 6-months (p=0.02). The mean baseline flattest (K1), steepest (K2), and overall keratometries (mean power) were 48.35 ± 3.65 D, 53.67 ± 3.38 D, and 50.84 ± 3.36 D, respectively. The 12-month mean ± standard deviations for flattest-K1, steepest-K2, and overall K were 46.53 ± 3.70 D, 49.83 ± 3.50 D, and 48.12 ± 3.49 D respectively, with statistically significant differences for all three topographic parameters (p=0.01). Conclusions: Ferrara intrastromal corneal ring segment insertions at a depth of 60% yield satisfactory visual, refractive, and keratometric results in keratoconic eyes.

RESUMO Objetivos: Este estudo aborda os resultados refrativos, topográficos, acuidade visual e tomografia de coerência óptica, 12 meses após a inserção do segmento de Anel de Ferrara em túnel corneano a 60% de profundidade com o laser de femtosegundo, em pacientes com ceratocone. Métodos: Série de casos não comparativos, prospectivos e intervencionistas. Realizamos a inserção do Anel de Ferrara através de incisão com o laser de femtosegundo em 15 olhos ceratocônicos. Foram incluídos pacientes com ceratocone documentado que voluntariamente assinaram consentimentos informados que tivessem melhor acuidade visual corrigida ≥0.30 tabela logMAR, espessura corneana ≥400µm. Foram excluídos pacientes com cirurgia ocular prévia ou curvatura corneana > 65 dioptrias (D). As principais variáveis medidas foram acuidade visual corrigida e os parâmetros topográficos da córnea (ceratometria mais plana (K1), mais curva (K2) e ceratometria média (K médio), avaliadas no pré-operatório e com 1, 3, 6 e 12 meses de seguimento. Resultados: A média ± desvio padrão da acuidade visual sem correção e acuidade visual corrigida foi 1.03 ± 0.46 e 0.42 ± 0.13, respectivamente; o desvio padrão médio de 12 meses, a acuidade visual sem correção e acuidade visual corrigida foram de 0.72 ± 0.37 e 0.31 ± 0.16, respectivamente, sem diferenças significativas (p=0,05 para ambos). A melhora da acuidade visual corrigida foi estatisticamente significante após 3 meses (p=0,02), e após 6 meses (p=0,02). Os valores médios da linha de base K1, K2, e média (K médio) foram 48,35 ± 3,65D, 53,67 ± 3,38D, e 50,84 ± 3,36D, respectivamente. A média de 12 meses ± desvio padrão para K1, K2, e K médio foi 46,53 ± 3,70D, 49,83 ± 3,50 D, e 48,12 ± 3,49D respectivamente, com diferença estatisticamente significativas para todos os 3 parâmetros topográficos (p=0,01). Conclusões: A inserção do Anel de Ferrara a uma profundidade de 60% no estroma corneano produz resultados visuais, refracionais e ceratométricos satisfatórios em olhos com ceratocone.

Clinical efficacy of SMILE in patients with different curvatures myopia and analysis of influencing factors / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To analyze the efficacy and influencing factors of femtosecond laser small incision lenticule extraction(SMILE)in the treatment of different curvature myopia.<p>METHODS: Totally 72 patients(144 eyes)with myopia who underwent SMILE were prospectively included. According to the preoperative corneal curvature, they were divided into low curvature group(<41D, <i>n</i>=21 cases, 42 eyes), middle curvature group(41-46D, <i>n</i>=26 cases, 52 eyes)and high curvature group(>46D, <i>n</i>=25 cases, 50 eyes). The refraction state, uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA)and corneal optical quality were compared among the groups before operation and at 1wk after operation and at 3mo after operation, and the influencing factors of SMILE visual acuity recovery in patients with myopia were screened out.<p>RESULTS: There were significant differences in UCVA and BCVA at different time points before and after operation within the three groups(<i>P</i><0.05), and there were no significant differences at different time points among groups(<i>P</i>>0.05). There were no significant differences in the spherical degree, cylindrical degree and spherical equivalent degree among the three groups at different time points(<i>P</i>>0.05). There was a statistically significant difference in the vector change value of subjective optometry refractive power(<i>P</i><0.05), and the value in low curvature group was lower than that in middle curvature group and high curvature group(<i>P</i><0.05). Multivariate Logistic regression analysis showed age, ocular axial length and preoperative spherical equivalent were related factors affecting the efficacy of SMILE surgery(<i>P</i><0.05).<p>CONCLUSION: SMILE can better improve the visual acuity of patients with different curvature myopia, and it is safe and effective, but age, ocular axial length and preoperative spherical equivalent are related factors affecting the visual acuity after SMILE.

Corneoscleral contact lenses fitting on irregular corneas after laser-assisted in situ keratomileusis / Lentes de contato corneoesclerais adaptadas em córneas irregulares após cirurgia LASIK

ABSTRACT Purpose: We aimed to describe the outcomes of corneoscleral contact lens fitting with multi-aspherical geometry designs in patients with irregular corneas after laser-assisted in situ keratomileusis (LASIK). Methods: This was a retrospective series of 18 patients (age, 26-38 years) selected from an eye clinic database. Participants were required to have unsatisfactory visual acuity with their current contact lenses or spectacles after LASIK for myopia correction. All patients were fitted with corneoscleral contact lenses designed to correct corneal surface irregularities. A diagnostic trial set was used for fitting, and assessments were performed according to a standardized methodology. Subjective comfort, visual acuity, central corneal thickness, endothelial cell count, and corneal-compensated intraocular pressure were evaluated. The follow-up period was one year. Results: Contact lens use was discontinued in 3 patients, thus leaving 24 eyes from 8 females and 7 males for analysis. The fitting characteristics were optimal in terms of lens position and movement. Statistically significant improvements were found in the best spectacle-corrected vision from before fitting to the visual acuity after fitting (p<0.001). Moreover, the patients reported high subjective comfort ratings and usage times (12.98 ± 2.3 hours/day). After one year of wear, visual acuity, subjective comfort, and usage time were maintained. No statistically significant adverse changes developed in the corneas over this period. Conclusion: Corneoscleral contact lenses with a multi-aspherical geometry design provide optimal visual acuity, improved comfort, and prolonged usage times in patients with irregular corneas after LASIK.

RESUMO Objetivo: Descrever os resultados do ajuste de lentes de contato corneoesclerais com geometria multiasférica em pacientes com córneas irregulares após cirurgia de ceratomileuse in situ assistida por laser (LASIK). Métodos: Esta foi uma série retrospectiva de 18 pacientes (idade, 26-38 anos) selecionados a partir de um banco de dados de uma clínica oftalmológica. Os participantes foram escolhidos ao manifestaram acuidade visual insatisfatória com suas lentes de contato ou óculos atuais depois de terem sido submetidos à LASIK para correção de miopia. Todos os pacientes receberam lentes de contato corneoesclerais projetadas para corrigir irregularidades na superficie da córnea. Um conjunto diagnóstico de prova foi usado para a adaptação e as avaliações foram feitas de acordo com uma metodologia padronizada. O conforto subjetivo, a acuidade visual, a espessura central da córnea, a contagem de células endoteliais e a pressão intraocular compensada da córnea foram avaliados. O período de acompanhamento foi de um ano. Resultados: O uso de lentes de contato foi descontinuado em 3 pacientes, deixando 24 olhos de 8 mulheres e 7 homens para análise. As características de adaptação foram ótimas em termos de posição e movimento da lente. Melhorias estatisticamente significativas foram encontradas na melhoria da visão corrigida por óculos antes de se ajustar a acuidade visual após a adaptação (p<0,001). Além disso, os pacientes relataram altos índices subjetivos de conforto e tempo de uso (12,98 ± 2,3 horas/dia). Após um ano de uso, a acuidade visual, o conforto subjetivo e o tempo de uso foram mantidos. Não houve alterações adversas estatisti­camente significativas nas córneas ao longo deste período. Conclusão: As lentes de contato corneoesclerais com projeto geométrico multiasférico proporcionam acuidade visual ideal, maior conforto e tempo de uso prolongado em pacientes com córneas irregulares após o LASIK.

Focal phototherapeutic keratectomy for the treatment of apical leucoma syndrome / PTK focal para o tratamento da síndrome do leucoma apical

ABSTRACT The following report describes a case of apical leucoma syndrome after hyperopic photorefractive keratectomy following hyperopic laser in situ keratomileusis and the subsequent treatment of this complication with focal phototherapeutic keratectomy. The patient underwent focal transepithelial phototherapeutic keratectomy of 70 mm ablation and 1.5 mm diameter after pupil and ablation offset correction. After 1 year, significant improvement in vision was observed and only slight residual opacity remained on biomicroscopy and optical coherence tomography. Focal phototherapeutic keratectomy was effective and safe for the treatment of this complication.

RESUMO O relato a seguir descreve um caso da síndrome do Leucoma Apical após cirurgia ceratorrefrativa hipermetrópica depois de Laser hiperópico in situ keratomileusis, e o subsequente tratamento desta complicação com ceratectomia fototerapêutica focal. O paciente foi submetido à ceratectomia fototerapêutica focal transepitelial com ablação de 70 mm e diâmetro de 1,5 mm, após correção de offset pupilar. Depois de um ano, foi observada uma melhora significativa da acuidade visual permanecendo apenas leve opacidade residual na biomicroscopia e tomografia de coerência óptica. A ceratectomia fototerapêutica focal foi efetiva e segura para o tratamento desta complicação.

Pellucid marginal degeneration: postponing penetrating keratoplasty for over a decade / Degeneração marginal pelúcida: postergando o transplante de córnea em mais de uma década

Abstract Pellucid marginal degeneration (PMD) treatment can be challenging in moderate to advanced cases and penetrating keratoplasty should be avoided due to high risk of complications, such as graft rejection. We report a case of a 30-year-old female patient with PMD that was referred to our service with bilateral low visual acuity, worse in her right eye and contact lenses intolerance. We performed a corneal crescentic lamellar wedge resection that resulted in good useful vision and postponed the keratoplasty for eighteen years.

Resumo A degeneração marginal pelúcida (DMP) é uma ectasia corneana de difícil manejo em casos moderados e avançados. O transplante de córnea penetrante nesses pacientes deve ser evitado ao máximo tendo em vista que a descentração necessária do botão aumenta o risco de vascularização e consequentemente rejeição, além das dificuldades técnicas e possibilidade de deiscência de sutura devido ao afinamento corneano pronunciado característico desta ectasia. Nós relatamos o caso de uma paciente de 30 anos com DMP com queixa de baixa visual bilateral, pior no olho direito e intolerância a lentes de contato. Foi realizada ressecção lamelar em crescente neste olho, com excelente resultado, concedendo visão útil a paciente e postergando o transplante penetrante por dezoito anos.

Efficacy at early stage after FS-LASIK with accelerated corneal collagen cross-linking / 国际眼科杂志(Guoji Yanke Zazhi)

· AIM:To evaluate the safety and efficacy at early stage after femtosecond laser-assisted excimer laser in situ keratomileusis (FS-LASIK) combined with collagen cross-linking.· METHODS:Totally 30 myopia patients (60 eyes) received FS-LASIK combined with collagen cross-linking from July 2016 to August 2017 in our hospital were tested the uncorrected visual acuity (UCVA),Ks,Kf,surface regular index (SRI),surface asymmetry index (SAI) by corneal topography (TMS) preoperatively,1,3mo after operation.The corneal compensated intraocular pressure (IOPcc),Goldmann correlated IOP value (IOPg),corneal resistance factor (CRF),corneal hysteresis (CH) tested by ocular response analyzer (ORA) were also observed.Ziemer Galilei Dual Scheimpflug Analyzer detected the anterior diopter and the corneal thickness.Endothelial cell density were examined.· RESULTS:The postoperative UCVA remained beyond 0.8 including 26 eyes (43％) of 1d,55 eyes (92％) of 1mo,50 eyes (83％) of 3mo.IOPcc,IOPg,CRF,CH at postoperative 1mo significantly decreased comparing with preoperative (P＜0.01).IOPcc,IOPg,CRF,CH at postoperative 3mo did not change significantly comparing with 1mo (P＞0.05).The corneal topographic map parameters of Ks and Kf significantly decreased at postoperative 1mo (P ＜ 0.01),while SRI and SAI increased significantly (P＜0.01) on comparison of 1mo and preoperative.Ks of postoperative 3mo was significantly higher than that of 1 mo (P＜0.05),while Kf did not change significantly (P＞ 0.05).There was a significant decrease in SRI and SAI between 3mo and 1mo after operation (P＜ 0.05).In Galileo analysis on comparison of 3mo and 1mo,Sim Ks,Sim Kf had 0.94D,0.95D growth and the front and back surface value of Kf increased more at 3mo postoperative (P＜0.01),while Ks was no significant difference (P＞ 0.05).There was no statistically significant difference in corneal thickness between the central point and the thinnest point (P＞ 0.05).There was no significant endothelial cell loss throughout follow up (3059.95±247.87/mm2 vs 3052.87± 267.71/mm2;t=0.279,P＞0.05).· CONCLUSION:Refractive corneal surgery combined with collagen cross linking for high degree,thin cornea,uneven thickness of the cornea,topographic anomalies except for the patients with keratoconus,play a role in stabilizing corneal shape and increasing corneal biomechanics early.