Focusing on preoperative evaluation for cataractous eyes after implantable collamer lens / 中华实验眼科杂志

With increasing age, more and more patients with posterior chamber intraocular lens (ICL) implantation are facing the threat of cataracts to their visual acuity.When examining the eyes of cataract patients after ICL surgery, attention should be paid to whether the density of corneal endothelial cells is greater than 2 000 cells/mm 2, the state of the anterior chamber angle, and whether there are fundus abnormalities such as retinal detachment and choroidal neovascularization.When conducting eye biometry measurement, attention should be paid to the measurement starting and ending lines of anterior chamber depth and lens thickness.If patients undergo ICL combined with corneal refractive surgery, they should be examined with two or more devices to obtain corneal refractive power according to the examination requirements after corneal laser vision correction.When selecting the type of intraocular lens, consideration should be given to the histological characteristics of high myopia.Compared to C- and L- loops, plate-haptic is relatively more stable in patients with high myopia accompanied by large capsules and larger diameters of continuous curvilinear capsulorhexis.Kane, Barrett Universal Ⅱ, Olsen, Hill-RBF formulas for calculating the refractive power of intraocular lenses are more accurate in people with long axial length.It is recommended to perform ICL removal simultaneously with phacoemulsification and intraocular lens implantation, preferably with a surgical incision greater than 2.6 mm.Femtosecond laser assisted cataract extraction surgery, although superior to traditional phacoemulsification in reducing corneal endothelial cell loss, reducing corneal edema, and high-quality capsulorhexis, can cause incomplete capsulorhexis and fragmentation due to the cavitation bubbles, manual adjustment of location, and the impact of lower vault.It is recommended to use it with caution.Ophthalmologists should fully understand and pay attention to the characteristics and difficulties of cataract surgery after ICL surgery, communicate fully with patients, and make personalized surgery to achieve better visual outcomes.

Comparison of vault measurements by Scansys, Pentacam, CASIA and Arcscan after ICL implantation / 中华实验眼科杂志

Objective:To evaluate the consistency of the Chinese three-dimensional anterior visual field analysis system (Scansys), the anterior segment analyzer (Pentacam), the frequency-domain anterior segment optical coherence tomography system (CASIA SS-1000), and a new ultra-high frequency digital ultrasound scanning system (Arcscan Insight100) to measure central vault after implantable collamer lens (ICL) implantation in myopic eyes with crystalline lenses.Methods:A diagnostic test study was conducted.Fifty-six myopic patients (56 eyes) who underwent ICL V4c implantation from June to December 2019 were included.Scansys, Pentacam, CASIA and Arcscan were used to measure the central vault after surgery.The vault measurements were compared.Correlations between the measurements of the four instruments were analyzed using Pearson correlation analysis, and consistency comparisons were analyzed using the Bland-Altman method.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Henan Eye Hospital (No.HNEECKY-2021[13]). Written informed consent was obtained from each subject.Results:The central vault measurements by Scansys, Pentacam, CASIA and Arcscan were (481.8±191.6), (476.4±190.6), (619.3±207.5) and (534.0±221.2)μm, respectively, with a statistically significant overall difference ( F=143.301, P<0.001). The vault measurements by Scansys and Pentacam were significantly lower than CASIA and Arcscan, and Arcscan was lower than CASIA, with statistically significant differences (all at P<0.001). There were strong positive correlations in vault measurements between Arcscan and CASIA, Arcscan and Pentacam, Arcscan and Scansys, CASIA and Pentacam, CASIA and Scansys, Pentacam and Scansys ( r=0.982, 0.933, 0.931, 0.942, 0.941, 0.989; all at P<0.001). Intraclass correlation coefficients of vault measurements by Scansys, Pentacam, CASIA and Arcscan were 0.985, 0.975, 0.998, 0.992, respectively.The 95% limits of agreement of vault measurements differences were -170 to 0, 0 to 280, 0 to 280, -110 to 210, -100 to 220 μm, between CASIA and Arcscan, CASIA and Scansys, CASIA and Pentacam, Arcscan and Scansys, Arcscan and Pentacam, respectively, and the maximum absolute value of the difference was beyond the clinically acceptable range, showing poor agreement.The 95% limits of agreement of vault measurement difference was -60 to 50 μm between Scansys and Pentacam, showing a good agreement. Conclusions:The repeatability of the vault after ICL V4c implantation in myopic eyes measured by the four instruments is good.Among them, the vault measurements of Scansys and Pentacam are smaller, showing good consistency, and their results could be substituted for each other.The measurement of CASIA is the largest, followed by Arcscan, which have a large difference from each other, and their results can not be substituted for each other, which should be comprehensively analyzed with the actual situation in clinical work.

Relationship between lens parameters and ocular anatomical characteristics in myopia patients / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the relationship among lens parameters and their correlation with ocular anatomic characteristics in myopia patients implanted with posterior-chamber phakic implantable collamer lens(Phakic-ICL).METHODS:Retrospective study. A total of 46 myopia patients(46 eyes)who underwent Phakic-ICL implantation were collected in the Wuxi Huaxia Eye Hospital from June 2022 to June 2023. Preoperative evaluation of ocular anatomical characteristics included corneal central thickness(CCT), anterior chamber depth(ACD), axial length(AL), white-to-white(WTW), horizontal sulcus to sulcus(STSH), horizontal angle to angle(ATAH), and vertical sulcus to sulcus(STSV), vertical angle to angle(ATAV). Furthermore, lens parameters included horizontal crystalline lens rise(CLRH), vertical CLR(CLRV)and vertical lens thickness(LTV). The difference, consistency and correlation of the above parameters were analyzed.RESULTS:Except for differences between WTW and STSV, STSH and ATAV, which were not statistically significant(all P&#x003E;0.05), the other horizontal and vertical ocular anatomical characteristics were statistically significant(P&#x003C;0.05). CLRH and CLRV had statistically significant difference(P&#x003C;0.01), while LTH and LTV were not statistically significant difference(P&#x003E;0.05). Bland-Altman results revealed that the anatomical characteristics in the horizontal or vertical diameters showed poor consistency. The consistency between CLRH and CLRV was poor. There was consistency between LTH and LTV, with the 95% limits of agreement(LoA)between the differences ranging from -0.21 to 0.28 mm, and the proportion of out-of-line points off the 95% LoA was 4.35%. Pearson correlation analysis revealed that there were correlations between the anatomical characteristics of the horizontal and vertical diameters(P&#x003C;0.01). Meanwhile, there was no correlation between the anteroposterior diameters(P&#x003E;0.05). There were correlations between the lens parameters(P&#x003C;0.05), excepted for the CLRH, LTH and LTV, which had no correlation. AL correlated with the anatomical characteristics of the horizontal and vertical diameters(P&#x003C;0.05), but it had no correlation with lens parameters(P&#x003E;0.05). Multiple linear regression analysis revealed that LT=0.419+0.017×age-0.548×ACD+0.371×ATAH+0.884×CLRV, CLRH=-0.443+0.809×CLRV, CLRV=-0.092-0.200×ATAH+0.560×CLRH(corrected R2=0.458, 0.482, 0.589, respectively).CONCLUSION:Horizontal and vertical diameters were not interchangeable. CLRH and CLRV were not interchangeable, while LTH and LTV were interchangeable. Partial lens parameters, WTW, STS, and ATA were correlated with ACD. Finally, age, ACD, ATAH, and CLRV influenced LT.

Comparison of clinical efficacy and stability of Toric implantable collamer lens implantation in different orientations / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the clinical efficacy, vault, and rotational stability of horizontal, oblique, and vertical implantation of Toric implantable collamer lens(TICL).METHODS: Retrospective cohort study. A total of 92 cases(120 eyes)who underwent TICL implantation from July 2018 to March 2022 and had regular follow-up for at least 1 a postoperatively(1 d, 1 wk, 1, 3, 6 mo, and 1 a)at Wuhan Bright Eye Hospital were collected. The patients were divided into three groups, with 34 cases(45 eyes)in horizontal implantation group, 25 cases(29 eyes)in oblique implantation group(29 cases), and 33 cases(46 eyes)in vertical implantation group. Uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), diopters, vault, and rotation angle(deviation of the actual axis of TICL from the expected axis).RESULTS: All surgeries were uneventful, and there were no complications such as infection, secondary glaucoma, or cataract opacity. Safety and efficacy of the surgery: the CDVA of the three groups of patients was better than or equal to the preoperative CDVA at 1 a postoperatively, and there was no statistically significant differences in postoperative UDVA and CDVA of the three groups(P&#x0026;#x003E;0.05). The safety index at 1a postoperatively was 1.34±0.21, 1.34±0.17, and 1.31±0.18 for the horizontal, oblique, and vertical groups, respectively. The efficacy index was 1.26±0.21, 1.33±0.18, and 1.27±0.16 for the three groups, respectively, both with no statistically significant differences(P&#x0026;#x003E;0.05). Vault: there was a significant difference in postoperative vault among the three groups(P=0.003), with the vertical group having the lowest vault, followed by the horizontal group and the oblique group. The vaults at different follow-up time points within each group showed significant differences(P&#x0026;#x003C;0.001), and all decreased over time. Residual astigmatism: there was no significant difference in residual astigmatism among the three groups(P=0.130), but there were differences at different follow-up time points within each group(P&#x0026;#x003C;0.001). Rotation angle: no significant differences in rotation angle were observed among the three groups(P=0.135), but there were differences at different follow-up time points within each group(P&#x0026;#x003C;0.001).CONCLUSION: The implantation of TICL in different orientations has good safety and efficacy, the postoperative rotational stability is good, and the appropriate angle can be selected to implant TICL according to the clinical situation.

Research progress of long-term efficacy after implantation of implantable collamer lens V4c / 国际眼科杂志(Guoji Yanke Zazhi)

With the rapid development of science and technology and the wide application of electronic products, the number of patients with high myopia is gradually increasing. Meanwhile, owing to the continuous optimization of surgical skils and the continuous advancement in materials of posterior chamber intraocular lens and manufacturing processes, implantable collamer lens(ICL)V4c implantation has gradually become one of the main surgeries for the treatment of high myopia. In the rapid era of social information, people pay more attention to the long-term efficacy after ICL V4c implantation, they not only want clear vision, but also the pursuit of visual comfort and durability. Therefore, this paper will specifically discuss the research progress of the post-implantation efficacy of ICL V4c with at least 2 a of follow-up observation within 3 a, aiming to review the latest research progress on the long-term efficacy of ICL V4c implantation from the three dimensions of visual quality, safety, efficacy and stability and possible surgical complications after ICL V4c implantation.

Evaluation of early binocular visual function after implantable collamer lens V4c implantation in patients with high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the binocular visual function in high myopia patients after the implantation of implantable collamer lens(ICL)V4c.METHODS: A total of 35 cases(70 eyes)that received binocular ICL implantation at our hospital from May 2019 to May 2021 were enrolled in this prospective study. Binocular full-range visual acuity, contrast sensitivity, stereopsis, mesopic vision and glare sensitivity, and monocular wavefront and the quality of vision questionnaire were assessed before the surgery and at 1 mo postoperatively.RESULTS: At 1 mo postoperatively, 35 cases(100%)had binocular uncorrected distance visual acuity(UDVA)≤0.00(LogMAR), 16 cases(46%)had binocular UDVA≥preoperative corrected distance visual acuity(CDVA). Binocular UDVA and uncorrected intermediate visual acuity(UIVA,80 cm)were improved compared to preoperative CDVA and distance-corrected intermediate visual acuity(DCIVA,80 cm)(all P&#x003C;0.05).While there were no differences in the binocular postoperative UIVA(60 cm)and preoperative DCIVA(60 cm),and uncorrected near visual acuity(UNVA,40 cm)and preoperative distance-corrected near visual acuity(DCNVA,40 cm)(all P&#x003E;0.05). The binocular contrast sensitivity was significantly improved postoperatively(P=0.001), and the postoperative binocular mesopic vision, glare sensitivity(no glare/glare)and binocular stereopsis(5 m/40 cm)had no differences(all P&#x003E;0.05). The postoperative total higher-order aberration, trefoil aberration, coma and spherical aberration were increased, besides the median of total coma in the right eye with a pupil diameter of 3.0 mm was decreased after surgery. The mean total score of quality of vision questionnaire was significantly increased from 54.87 preoperatively to 80.92 after implantation(P&#x003C;0.05), with high satisfaction and no obvious visual disturbance in patients.CONCLUSION: Although the monocular high-order aberrations increased in the early stage after ICL V4c binocular implantation in patients with high myopia, the binocular visual function was improved.

Vector analysis of toric implantable collamer lens V4c implantation in correcting moderate to high myopia with high astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the clinical effect of toric implantable collamer lens(TICL)V4c for correcting moderate to high myopia with high astigmatism using vector analysis and quality of life impact of refractive correction(QIRC).METHODS: Retrospective case series. A total of 55 patients(90 eyes)with moderate to high myopia and high astigmatism who received TICL V4c implantation in the refraction surgery center of ophthalmology department in our hospital from January 2019 to December 2022 were collected. Followed-up for 1 a, the uncorrected distance visual acuity(UDVA), best corrected visual acuity(BCVA)and diopters were observed. Alpins vector analysis was used to evaluate the effect of astigmatism correction, and QIRC scale was used to evaluate patients' quality of life.RESULTS: At 1 a postoperatively, the UDVA of 98% eyes was the same or better than pre-operative BCVA, the safety index was 1.11±0.14, and the efficacy index was 1.11±0.15. The angle of error of 97% of the astigmatic eyes was within ±15°. The results of vector analysis showed that correction index was 0.83±0.13, angle of error was 1.00±4.49°, and index of success was 0.21±0.15. The total higher order aberrations under a pupil diameter of 6 mm was significantly increased compared with preoperatively(P&#x003C;0.05), the QIRC score was significantly better than that before surgery(P&#x003C;0.001), and the increase of total QIRC scores was positively correlated with preoperative spherical equivalent(rs=0.215, P&#x003C;0.05), indicating that the higher degree of myopia before surgery the patients, the better the quality of life after TICL implantation.CONCLUSION: TICL V4c implantation for the correction of moderate to high myopia with high astigmatism is safe and effective, and the patients' quality of life significantly improved after surgery.

Early outcomes of anterior segment parameters in patients with high myopia after implantable collamer lens V4c implantation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To study the early outcomes of anterior segment parameters after implantation of an implantable collamer lens with a central hole(ICL V4c)in patients with high myopia.METHODS:A total of 82 cases(160 eyes)with high myopia, including 42 males(82 eyes)and 40 females(78 eyes), aged 26.0±4.6(21 to 37)years, who underwent ICL V4c implantation at our institution from February 2019 to September 2022 and were followed up for 1 a, were included. The general characteristics of the anterior segment of the eye were measured preoperatively: spherical equivalent, mean horizontal corneal curvature, white-to-white(WTW), and axial length(AL); intraocular pressure(IOP), endothelial cell density(ECD), central anterior chamber depth(CACD), anterior chamber volume(ACV)and anterior chamber angle(ACA)were measured preoperatively and at 1 d, 1 wk, 1, 3 and 6 mo postoperatively. Furthermore, the distance from the centre of the posterior surface of the ICL V4c optical zone to the anterior surface of the lens(vault)was measured at 1 d, 1 wk, 1, 6 mo, and 1 a after surgery.RESULTS: The mean preoperative spherical equivalent of the patients was -7.56±2.55 D, mean horizontal corneal curvature was 42.89±1.47 D, WTW was 11.64±0.37 mm, and AL was 26.64±0.93 mm. The baseline IOP was 15.97±2.13 mmHg, and the differences in IOP at each time point after ICL V4c implantation compared to preoperative were not statistically significant(F=0.875, P=0.504); ECD was 2 989.30±140.78 cells/mm2 at baseline, and ECD at 6 mo after ICL V4c implantation was not statistically significant compared with preoperative ECD(t=1.475, P=0.142); CACD was 3.19±0.21 mm at baseline, and ACV was 210.30±27.7 mm3, and CACD and ACV were significantly lower than preoperative at all postoperative time points(F=111.10, 288.38, all P&#x003C;0.001). The baseline ACA was 35.44°±11.27°, and the ACA at each time point after ICL V4c implantation was significantly lower than preoperatively(F=21.23, P&#x003C;0.001). The vault was 665.32±184.03 μm at 1 d postoperatively, and continued to be significantly reduced at 1 wk, 1, 6 mo, and 1 a postoperatively compared with 1 d(F=52.10, P&#x003C;0.001). However, it remained stable at 6 mo and 1 a postoperatively, and the difference was not statistically significant compared with vault at 1 mo postoperatively(P&#x003E;0.05).CONCLUSION: ICL V4c has certain safety and efficiency in 1 a postoperative follow-up, and the parameters of the anterior segment of the eye stabilized in the early period.

Refractive reconstruction of keratoconus / 国际眼科杂志(Guoji Yanke Zazhi)

Keratoconus is a progressive disease that seriously affects the eyesight of young people. Keratoconus often causes high myopia, irregular astigmatism, and some patients with advanced corneal scar, visual acuity significantly decreased. In the course of diagnosis and treatment of keratoconus, refractive reconstruction of keratoconus is the focus of clinical attention. After years of research and exploration, a variety of treatment methods in different stages of disease(non-progressive, progressive, advanced)for keratoconus patients refractive reconstruction, so that they can obtain good visual function. This paper mainly reviews the refractive reconstruction schemes of keratoconus in different periods, analyzes the advantages and disadvantages of various treatment schemes at home and abroad, and summarizes the characteristics of different treatment methods, with a view to providing theoretical reference and new treatment ideas for the diagnosis and treatment of keratoconus.

Research progress in optimizing implantable collamer lens V4c implantation / 国际眼科杂志(Guoji Yanke Zazhi)

With the development of posterior chamber phakic intraocular lenses implantation and the constant improvement of the implantable collamer lens(ICL), ICL V4c implantation has become one of the main methods for correcting moderate and high myopia. Vault is an important indicator to evaluate the security of posterior chamber intraocular lens implantation. In recent years, optimizing surgical procedures to obtain the ideal vault in ICL V4c implantation surgery has become a research hotspot. This paper aims to provide help for improving surgical safety by summarizing and analyzing the optimized programs of ICL V4c implantation surgery. The focus will be on preoperative examination, intraoperative surgical design, and postoperative follow-up.

Research advances in the size selection of implantable collamer lens / 国际眼科杂志(Guoji Yanke Zazhi)

The implantable collamer lens(ICL)is a widely popular option for the correction of refractive errors. ICL implantation brings a whole new dimension to the vision, from the anterior chamber phakic ICL to the posterior and central hole ICL. Even though there are fewer reported complications, ICL size selection remains challenging due to the differences in device measurements and ICL sizing formulas. With the widening comprehensiveness of ICL implantation and the ongoing development of ophthalmic devices and technologies, particularly the advent of artificial intelligence, more and more indicators such as sulcus-to-sulcus(STS), crystalline lens rise(CLR), angle-to-angle(ATA), the iris pigment end to the iris pigment end(PTP), anterior chamber width(ACW), and anterior chamber angle(ACA)are providing references in the selection of ICL size, this article provides a review of ICL size selection.

Efficacy of implantable collamer lens V4c implantation in the treatment of high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe the effect of implantable collamer lens V4c(ICL V4c)implantation on high myopia, and the changes in anterior segment morphology.METHODS:A prospective study was conducted on 100 patients(200 eyes)with high myopia who were treated with ICL V4c implantation in the hospital from February 2018 to March 2021. The best corrected visual acuity(BCVA), uncorrected visual acuity(UCVA), intraocular pressure, higher-order aberration, anterior segment morphology [iridocorneal angle(ICA), central anterior chamber depth(ACD), anterior chamber volume(ACV), central corneal thickness(CCT)and K-value(K)], photopic and scotopic contrast sensitivity before operation and 6 and 12mo after operation were comparatively analyzed.RESULTS:All patients were followed-up. UCVA and BCVA were significantly improved at 6 and 12mo after operation(P&#x003C;0.05). Total higher-order aberration, horizontal coma and vertical coma showed no significant difference before and after operation(P&#x003E;0.05). Spherical aberration, ICA, ACD and ACV at 6 and 12mo after operation were significantly smaller than those before operation(P&#x003C;0.05). Under photopic state, the contrast sensitivity of 3.0 and 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P&#x003C;0.05). Under scotopic state, the contrast sensitivity of 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P&#x003C;0.05); there was no significant difference in CCT, K, or intraocular pressure before and after operation(P&#x003E;0.05).CONCLUSION:Although ICA, ACD and ACV in patients with high myopia are reduced after ICL V4c implantation, the operation can effectively improve visual acuity and visual quality.

Research progress on visual quality and complications after implantable collamer lens implantation / 国际眼科杂志(Guoji Yanke Zazhi)

Corneal refractive surgery and intraocular collamer lens(ICL)implantation are the mainstream refractive surgery methods at present. Many studies have proved that ICL implantation can effectively improve the postoperative visual acuity of patients. ICL implantation has gained favor among refractive doctors and patients because of its multiple advantages. Excellent postoperative visual acuity and visual quality are the key factors to improve patients' satisfaction. In order to evaluate the subjective and objective visual quality of patients after operation and avoid complications, this article reviews the visual quality and postoperative complications after ICL implantation.

Research progress on position stability and visual quality changes in the eye after implantable collamer lens implantation / 国际眼科杂志(Guoji Yanke Zazhi)

Implantable collamer lens(ICL)and toric ICL(TICL)are clinically common types of posterior chamber phakic intraocular lenses, they are mainly used to correct high myopia and low-to-moderate myopia of eyes whose corneal conditions are not suitable for corneal laser surgery. Accurate preoperative measurement, safe intraoperative implantation and appropriate postoperative location of lenses are critical to ensure the outcome of ICL implantable, and the appearance of V4c ICL with a central hole ensures the safety of this surgery to a greater extent. However, the intraocular position of both ICL and TICL is not invariable. Some studies have shown that the vault has a trend of decreasing year by year after ICL surgery, but its reason is unknown. And spontaneous rotation may occur after the TICL surgery, thereby causing visual loss, which is one of the main causes of TICL replacement. And postoperative changes in the position of the central hole also need attention. In addition, the visual quality of the operated eye will change after ICL/TICL implantation, but whether the change of intraocular positions of implanted lenses will affect the postoperative visual quality is also a problem that needs to be paid attention to and explored. Therefore, this paper reviewed the postoperative changes in vault, TICL axis, position of the central hole and their causes, as well as the effects of these changes on postoperative visual quality, offering valuable clinical guidance for accurate preoperative selection of ICL/TICL and surgical design, so as to improve the effectiveness and stability of ICL implantation in correction of myopic refractive error.

Short-term visual quality observation of femtosecond laser small incision lenticule extraction and evolution implantable collamer lens implantation in the correction of moderate myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the short-term visual quality outcomes after femtosecond laser small incision lenticule extraction(SMILE)and evolution implantable collamer lens(EVO-ICL)implantation for the correction of moderate myopia.METHODS: Prospective control study. A total of 51 cases(51 eyes)with moderate myopia who underwent SMILE or EVO-ICL implantation surgery at Weifang Eye Hospital from April 2021 to February 2022 were selected. They were divided into SMILE group(30 patients, 30 eyes)and EVO-ICL group(21 patients, 21 eyes)according to the surgical methods. The changes of visual acuity [uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA)], diopter [spherical equivalent(SE)] and related parameters of optical quality analysis system(OQAS Ⅱ)were observed before surgery and at 1wk, 1 and 3mo after surgery, and the quality of vision(QoV)questionnaire was completed.RESULTS: At 3mo after surgery, the safety index(postoperative CDVA/preoperative CDVA)of SMILE gruop and EVO-ICL group were 1.20(1.00, 1.20)and 1.20(1.00, 1.38), respectively, the efficacy index(postoperative UDVA/preoperative CDVA)were 1.00(1.00, 1.20)and 1.00(1.00, 1.20), respectively, and the percentage of SE within ±0.50D was 87% and 100%, respectively. In SMILE group, the objective scattering index(OSI)was increased after surgery, while modulation transfer function cutoff frequency(MTF cutoff), contrast visual acuity(VA)100%, and VA20% at 1wk and 1mo after surgery, and Strehl ratio(SR)and VA9% at each time point after surgery were all decreased compared with those before surgery(all P&#x0026;#x003C;0.05). The OSI, MTF cutoff, SR and VA of EVO-ICL group showed no difference at each time point after surgery compared with those before surgery(all P&#x0026;#x003E;0.05). The most common visual symptoms after SMILE and EVO-ICL implantation were visual haze and halos, respectively.CONCLUSION: Both SMILE and EVO-ICL implantation have good safety, efficacy and predictability in the short term after the correction of moderate myopia. Both groups had visual symptoms after surgery, but the overall satisfaction of patients was high. Furthermore, EVO-ICL implantation has better objective visual quality performance.

Influencing factors of the early vault after phakic posterior chamber implantable collamer lens implantation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe the early variation trend of the vault after phakic posterior chamber implantable collamer lens/toric implantable collamer lens(ICL/TICL V4c)implantation and analyze the related influencing factors.METHODS:In this retrospective study, a total of 49 patients(98 eyes)who underwent ICL/TICL V4c implantation in the Lanzhou Huaxia Eye Hospital from October 2020 to March 2021 were enrolled. Preoperative ocular biometric parameters were collected, including spherical equivalent(SE), intraocular pressure, axial length, anterior chamber depth(ACD), lens thickness(LT), central corneal thickness, anterior chamber angle(ACA), anterior chamber volume(ACV), white to white corneal diameter(WTW), mean keratometry K1 and K2, and intraoperative implantation size of ICL. The vault was measured by anterior segment optical coherence tomography(AS-OCT)at 1, 3d, 1wk and 1mo after surgery. The patients were divided into insufficient vault group(&#x003C;250μm, 12 eyes), normal vault group(250-750μm, 62 eyes)and excessive vault group(&#x003E;750μm, 24 eyes)according to the vault at 1mo after surgery. The factors affecting the postoperative vault were analyzed.RESULTS:The mean vault values at 1 and 3d, 1wk and 1mo after surgery were 591.05±293.44, 599.62±309.78, 592.22±301.49 and 586.69±285.63μm, respectively. There were significant differences in WTW, ACA, ACV, ACD, ICL size and LT at 1mo after surgery(all P&#x003C;0.05). The regression equation of vault at 1mo after surgery was as follows: vault(μm)=-3142.19+388.25×WTW+10.40×ACA-301.63×LT(R=0.674, R2=0.454, adjusted R2=0.436). WTW had the greatest influence on vault at 1mo after surgery(β=0.47, P&#x003C;0.001), followed by LT(β=-0.34, P&#x003C;0.001)and ACA(β=0.17, P=0.047).CONCLUSION:WTW, ACA and LT were the main factors that affected and predicted the vault at 1mo after ICL/TICL V4c implantation.

Comparison of clinical effects of corneal topography-guided FS-LASIK and TICL implantation for myopia with moderate to high astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the clinical efficacy of the myopic with moderate to high astigmatism correction between corneal topography-guided femtosecond laser in situ keratomileusis(FS-LAISK)and Toric implantable collamer lens(TICL).METHODS: A total of 60 patients(115 eyes)with moderate to high astigmatism in myopia(115 eyes)from June 2019 to June 2021 and treated in the refractive center of Heyuan Aier Eye Hospital were enrolled in the study, then were divided into Group A and Group B according to the operations they would accept. There were 32 patients(62 eyes)in the Group A treated with corneal topography-guided FS-LASIK and 28 patients(53 eyes)in the Group B treated with TICL implantation. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), spherical diopter and residual astigmatism were recorded preoperatively and postoperatively at 3mo, surgical safety and efficacy were evaluated, and the Alpins vector analysis was used to evaluate the astigmatism.RESULTS: The postoperative at 3mo, there were no differences in the safety index(1.163±0.167 vs 1.136±0.194)and the efficacy index(1.145±0.159 vs 1.123±0.196)between the patients of the two groups(P&#x003E;0.05). However, the astigmatism vector analysis showed that there were statistically differences in the index of success index [0.125(0.091, 0.200)vs 0.200(0.167, 0.250)], the correction index [1.000(0.902, 1.066)vs 0.834(0.783, 0.869)] and the flattening index [1.000(0.922, 1.079)vs 0.835(0.795, 0.870)](P&#x003C;0.01).CONCLUSION:Corneal topography-guided FS-LASIK and TICL implantation were effective and safe in correcting myopia with moderate to high astigmatism, and corneal topography-guided FS-LASIK perform better than TICL implantation for the astigmatism correction.

Clinical efficacy of Toric ICL implantation and its effect on corneal astigmatism and aberration / 国际眼科杂志(Guoji Yanke Zazhi)

@#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.

Effect of crystalline lens rise on the vault after implantation of phakic posterior chamber implantable collamer lens / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To investigate the relationship between crystalline lens rise(CLR)measured by anterior segment-optical coherence tomography(AS-OCT)and parameters of the anterior segment. And also measure the effects of CLR on the vault after phakic posterior chamber implantable collamer lens(PPC-ICL)implantation.<p>METHODS:The study included 80 eyes of 40 patients who underwent PPC-ICL implantation at the Department of Ophthalmology, the Second Affiliated Hospital of Anhui Medical University, from July 2017 to July 2018, to measure the sulcus-to-sulcus(hSTS)distance of the eyes using a Compact Touch STS ultrasound biomicroscope and lens curvature(LC), Pentacam was used to measure horizontal-white-to-white(hWTW), anterior chamber depth(ACD)and the vault one year after the operation. Moreover, AS-OCT was used to measure the CLR and horizontal iridocorneal angle-to-iridocorneal angle diameter(ATA).<p>RESULTS:CLR was negatively correlated with ACD(<i>r</i>= -0.706, <i>P</i><0.01)and vault one year after the operation(<i>r</i>= -0.509, <i>P</i><0.01); however, it was positively correlated with LC(<i>r</i>=0.667, <i>P</i><0.01). There was no correlation between CLR and hWTW(<i>r</i>=0.123, <i>P</i>=0.275), ATA(<i>r</i>=0.208, <i>P</i>=0.065)and hSTS(<i>r</i>=0.147, <i>P</i>=0.194). One year after the operation, there was a positive correlation between the vault and ACD(<i>r</i>=0.680, <i>P</i><0.01).<p>CONCLUSION:CLR has obvious correlation with ACD and LC, arch height after PPC-ICL and has a specific effect on the prediction of the vault after PPC-ICL implantation.

Progress of posterior chamber implantable collamer lens implantation for the treatment of refractive errors / 国际眼科杂志(Guoji Yanke Zazhi)

@#Refractive errors are a common ophthalmic disease, which can be corrected by wearing glasses, laser refractive surgery and so on. However, there are some limitations of these methods for treating high myopia, keratoconus, <i>etc</i>. The implantation of the posterior chamber implantable collamer lens(ICL)is one of the most common surgry for correcting refractive errors(mainly apply to high myopia and astigmatism). This study aim to explore the safety and effectiveness of implanting ICL to correct low to moderate and high myopia or hyperopia. This review will summarize the research progress of implanting ICL to correct refractive errors.