Clinical prediction of insufficient vaults after implantable collamer lens implantation

AIM:To determine the factors related to preoperative ocular characters that are predictive of insufficient vault(<250μm)after implantable collamer lens(ICL V4c;STAAR Surgical)implantation.METHODS:The participants underwent ICL surgery and were divided into the low(<250μm)and normal(250-1000μm)vault groups based on the postoperative vault at 3mo.The preoperative biometric parameters and clinical outcomes were compared between the two groups.The relationship between the 3-month vault values and preoperative ocular parameters were evaluated by Generalized estimating equations.RESULTS:Sixteen(23 eyes)and 36 patients(63 eyes)were in the low and normal vault groups,respectively.All implantation procedures were uneventful with no cataract formation in the early postoperative period.The sulcusto-sulcus lens rise(STSL)and iris ciliary angle(ICA)were correlated with vault at 3mo after surgery.Every 0.1 mm increase in STSL was associated with 38.9μm decrease in the postoperative 3-month vault.A rise of 1 degree in ICA is associated with a reduction of 4μm in vault.CONCLUSION:Eyes with a narrow ciliary sulcus are associated with a higher rate of low vault after ICL implantation,suggesting a need for adjustments to the ICL size in these patients.Evaluating the characteristics of the ciliary sulcus contributes valuable information to predict low vault after surgery.

Transcapsular scleral fixation of the standard capsular tension ring and in-the-bag intraocular lens implantation for severely subluxated lenses

AIM:To present a technique of transcapsular scleral fixation of the standard capsular tension ring(CTR)through equatorial capsulotomy and in-the-bag intraocular lens(IOL)implantation in subluxated lenses.METHODS:This retrospective consecutive case series included patients with subluxated lenses by more than 180 degrees who underwent lens extraction,transcapsular scleral fixation of the standard CTR through equatorial capsulotomy,in-the-bag IOL implantation and with at least 6mo follow-up.Preoperative and postoperative best corrected visual acuity(BCVA),intraocular pressure(IOP),complications,and postoperative IOL tilt and decentration were recorded.RESULTS:Nine eyes of 7 patients with a mean followup of 11.0±3.7mo were included in this study.The BCVA was significantly improved from 0.64±0.22 logMAR preoperatively to 0.21±0.19 logMAR postoperatively(P<0.001).The IOP was within the normal range postoperatively.The mean tilt of the IOL was 4.30°±2.31°(range,1.0°to 8.9°)and the mean decentration of the IOL was 0.37±0.12 mm(range,0.14 to 0.50 mm).No visually threatened intraoperative and postoperative complications were detected during the follow-up period.CONCLUSION:This is a safe and effective surgical technique for managing patients with severely subluxated lenses.It has achieved favorable outcomes with fewer surgical manipulations and less need for advanced capsular support devices.

Effect of capsule treatment on visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataract

BACKGROUND Cataracts pose a significant clinical burden due to their complex pathogenesis.In recent years,an increase in cataracts coexisting with myopia has heightened the incidence of retinopathy and posterior vitreous detachment.Additionally,symptoms of ocular axis elongation,lens nucleus hardening,and vitreous liquefaction have become more prevalent.While conventional extracapsular cataract extraction is commonly employed,it often yields suboptimal visual outcomes.Subsequent advancements in cataract phacoemulsification and lens implantation surgeries have gained widespread acceptance for their ability to improve refraction and significantly improve uncorrected visual acuity.AIM To investigate the effect of capsular treatment after phacoemulsification lens implantation in myopic patients with cataract.METHODS We selected 110 patients(with 134 eyes)with myopia and cataracts treated.These patients were categorized into two groups:an observation group(57 patients with 70 eyes)and a control group(53 patients with 64 eyes).The control group underwent cataract phacoemulsification and lens implantation,while the observation group received a refined capsular treatment based on the control group’s procedure.We assessed the differences in visual acuity and quality between the two groups before and after surgery.RESULTS At six months post-operation,the observation group exhibited significantly improved far vision,intermediate vision,near vision,lower objective scattering index,higher Modulation transfer function cut-off frequency,and overall vision metrics at different contrast levels(100%,20%and 9%)compared to the control group(P<0.05).The total score of the National Eye Institute Visual Function Questionnaire in the observation group at 6 months after operation was significantly higher than that in the control group(P<0.05).No significant difference in the incidence of adverse reactions was observed between the observation group and control group(P>0.05).CONCLUSION Capsular treatment demonstrates efficacy in improving visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataracts,warranting its clinical application.

Clinical Effect Analysis of Posterior Chamber Intraocular Lens Implantation for Correcting High Myopia and Astigmatism

Objective:To explore the corrective effect of posterior chamber intraocular lens implantation with phakic eyes in the treatment of high myopia and astigmatism.Methods:From May 2023,the hospital began to collect the case data of diagnosis and treatment of high myopia and astigmatism.By May 2024,310 cases were included,all of which were treated with posterior chamber intraocular lens implantation.The visual acuity,astigmatism and axial position of the intraocular lens were observed before and after treatment.Results:At different time points after the operation,the patient’s vision was significantly improved compared with that before the operation(P<0.05),and the vision level was equal to or greater than the best-corrected vision before the operation.At different time points after the operation,the average rotation of the intraocular lens was less than 5 degrees.Astigmatism was significantly lower than that before the operation(P<0.05).After the operation,the intraocular pressure increased in 11 cases,accounting for 3.55%,with no adverse complications such as lens turbidity,glare and obvious halo occurring.Conclusion:The posterior chamber intraocular lens implantation with phakic eyes has an ideal correction effect in the treatment of high myopia and astigmatism,which can effectively improve the vision level of patients and reduce the degree of astigmatism,and has high effectiveness and safety.

Early clinical outcome with lens position adjustment following implantable collamer lens surgery

AIM:To observe early clinical outcome with lens position adjustment following the implantable collamer lens(ICL)surgery.METHODS:Sixty patients were selected for this retrospective study.One eye from each patient received Toric ICL for astigmatism correction,and the other received non-astigmatic ICL surgery using horizontal position.Patients with higher postoperative arch height were selected,and their non-astigmatic eye clinical outcome were observed after ICL surgery at 1wk,1,and 3mo.The clinical measurements included uncorrected visual acuity(UCVA),intraocular pressure(IOP),refractive state,corneal endothelium cell count,and arch height.Three months later,the ICL in each patient’s non-astigmatic eye was adjusted to the vertical from the horizontal position.The results were compared before and 1wk,1,and 3mo after adjustment.RESULTS:UCVA and IOP were significantly reduced 1wk after position adjustment compared to 1wk after ICL implantation(P<0.05).The patients demonstrated significantly reduced arch height and corneal endothelium cell count 1wk,1,and 3mo after adjusting position compared to 1wk,1,and 3mo after ICL implantation(P<0.05).However,there was no significant difference in refraction between 1wk,1,and 3mo after ICL implantation and position adjustment(P>0.05).CONCLUSION:Early positioning adjustment postphakic ICL implantation can benefit patients with adjusted arch height or higher IOP.Despite the good clinical effects,the doctors should pay attention to the potential for adverse effects on UCVA and corneal endothelium cells following early position adjustment after posterior chamber phakic ICL implantation.

Rhegmatogenous retinal detachment in highly myopic eyes with implantable collamer lens

AIM:To investigate the clinical characteristics,treatment methods and outcomes of rhegmatogenous retinal detachment(RRD)in highly myopic eyes with implantable collamer lens(ICL).METHODS:High myopia patients who received treatment for nontraumatic RRD after ICL implantation surgery at the Retinal Department of Zhongshan Ophthalmic Center from Jan 2018 to Dec 2022 were reviewed.Comprehensive ophthalmologic examinations including visual acuity measurement and digital fundus photography were performed in each patient.RESULTS:A total of nine RRD eyes from nine patients who received V4c-ICL implantation were included.The mean time from ICL implantation surgery to the diagnosis of RRD was 32.44±22.56mo(range,1-60mo).At the initial visit for RRD,giant retinal tear(GRT),horseshoe tear,simple round hole,and horseshoe tear combined with round hole were detected in 3,3,2,and 1 eye(s),respectively,with maculaoff in eyes.Eight patients received surgical treatment,and one patient was treated by retinal laser photocoagulation alone.The ICL was preserved in 7 eyes.At the last followup,the mean best corrected visual acuity(BCVA)improved significantly from 1.76±1.06 logMAR at presentation to 0.81±1.01 logMAR(P=0.035),and no case of recurrent retinal detachment was found.CONCLUSION:The morphological presentation of retinal breaks is diverse in this study.The ICL can be preserved in most cases during the course of retinal detachment repair surgery in our data,companied with acceptable visual and anatomical outcomes.

Posterior chamber phakic intraocular lens implantation for high myopia

AIM:To evaluate the efficacy,safety and stability of posterior chamber phakic intraocular lens implantation for the correction of high myopia.METHODS:Retrospective case review of 82 eyes(43patients)undergoing implantable Coliamer lens(ICL)placement by a single surgeon(Xiao-Wei Gao)to correct preoperative mean spherical equivalents between-9.00diopter(D)and-23.00D.Main outcome measures included uncorrected visual acuity(UCVA),refraction,best spectacle-corrected visual acuity(BSCVA),endothelial cell density(ECD),intraocular pressure(IOP),lens transparency,postoperative uveitis.Visante anterior segment optical coherence tomography(AS-OCT)was used to measure anterior chamber depth(ACD)and the position of ICL.RESULTS:Mean follow-up was 6.54±3.26 months(range 3-12 months).Predictability of the manifest spherical equivalent(SE)refraction to within±1.OOD was achieved in 88%of eyes and±0.50D in 72.5%of eyes.The mean postoperative manifest SE refraction was-1.85±0.72D,with 96.34%of eyes maintaining or gaining≥1 line(s)of BSCVA.The mean 3-month postoperative ECD decreased but had no statistically difference compared with the preoperative ECD.Of the 7 eyes(8.54%)with a mild transient increase in intraocular pressure(up to 30mmHg),none required a second surgical procedure or prolonged topical medication.There was no loss of lens transparency.Pigmented precipitates were observed in 5 eyes(6.09%).The mean preoperative ACD measured with AS-OCT was 3.28±0.14mm,three months after surgery,the mean ACD was2.45±0.22mm.Anterior chamber depth showed astatistically significant reduction.One eye(1.22%)had ICL spontaneous rotation,81 eyes(98.78%)of the lens remained correctly centered.CONCLUSION:The implantation of ICL is an effective surgical option for the management of high myopia.But its long time effect and safety still need more time to prove.

Visual performance after implantation of two types of phakic foldable intraocular lenses for correction of high myopia

AIM: To compare Visian lens(model V4 c) and Artiflex lens regarding quality(contrast sensitivity) and quantity(efficacy, predictability, safety and stability) of vision in correcting high myopia with recording and analysis of complications. METHODS: The comparative prospective study included 39 eyes of 23 patients with high myopia, 19 eyes had Visian lens implantation(model V4 c) and 20 eyes had Artiflex lens implantation. The inclusion criteria were high myopia(higher than 6.0 D) and stable refraction(<0.5 D change over one year). Outcomes included assessment of safety and efficacy indices, predictability, stability, contrast sensitivity and analysis of complications at postoperative 1 d, 1 wk and 1, 3, 6 and 12 mo. Selection of the type of phakic intraocular lens for patients was based on surgeons' preferences, which was no specific selection criteria. RESULTS: After 12 mo of follow up, difference in uncorrected and corrected distant visual acuity(CDVA) between both groups was statistically insignificant(UDVA for VisianV4 c and Artiflex lens were 0.33±0.2 logMAR and 0.37±0.2 logMAR respectively, P=0.59, CDVA for VisianV4 c and Artiflex lens were 0.155±0.1 logMAR and 0.147± 0.1 logMAR respectively, P=0.87). The efficacy index was 1.25 for VisianV4 c lens and 0.8 for Artiflex lens, 78.9% of eyes were within one diopter spherical equivalent in Visian V4 c lens group compared to 70% in the Artiflex lens group. No eye lost lines of CVDA proving a good safety index for both lenses(safety index was 1.67 for VisianV4 c lens and 1.34 for Artiflex lens). Difference in contrast sensitivity between both groups was statistically insignificant(P=0.15, 0.88, 0.27, 0.32 and 0.82 at five spatial frequencies). CONCLUSION: Both Visian ICL V4 c and Artiflex lensesare safe and effective with stable and predictable refraction and they have comparable contrast sensitivity outcomes with no vision threatening complications.

Outcomes of secondary sulcus intraocular lens implantation in unilateral anterior persistent fetal vasculature

AIM: To evaluate the surgical results of sulcus intraocular lens(IOL) implantation in children with unilateral anterior persistent fetal vasculature(PFV) underwent primary vitrectomy combined with lensectomy and preservation of the peripheral anterior capsule.METHODS: Twenty-two eyes of 22 children with unilateral anterior PFV who underwent sulcus secondary IOL implantation were analyzed. Main outcome measures were preoperative and postoperative visual acuity, and complications both intraoperatively and postoperatively. RESULTS: Review of 22 consecutive patients identified best-corrected visual acuity(BCVA) improvement from 1.37±0.84 to 0.73±0.57 logarithm of the minimal angle of resolution(logMAR) after IOL implantation(P<0.001) with a mean follow-up was 16.55±5.86 mo. Average age at secondary IOL implantation was 41.05±15.41 mo. Three eyes(13.64%) achieved BCVA of 0.3 logMAR at the final visit. Transient intraocular pressure rise(4 eyes; 18.18%), postoperative increased inflammation(3 eyes; 13.64%) and postoperative hypotony(2 eyes; 9.09%) were common complications.CONCLUSION: Properly preservation of the anterior lens capsule during the primary surgery facilitated secondary sulcus IOL implantation in pediatric patients with anterior PFV, with favorable postoperative visual outcomes and compatible percentage of complications.

Diffractive multifocal intraocular lens implantation in patients with monofocal intraocular lens in the contralateral eye

AIM:To evaluate clinical outcomes of unilateral implantation of a diffractive multifocal intraocular lens(IOL)in patients with contralateral monofocal IOL.METHODS:Twenty-two patients who already had implantation of a monofocal IOL in unilateral eye underwent implantation of a diffractive multifocal IOL in contralateral eye were enrolled.After 1,6,and 12 mo,uncorrected and distant corrected distant visual acuity(UCDVA and DCDVA),uncorrected and distant corrected intermediate-visual acuity(UCIVA and DCIVA),uncorrected and distant corrected near visual acuity(UCNVA and DCNVA),and contrast sensitivity were obtained.Halo/glare symptoms,spectacle dependence,and patient satisfaction were also evaluated.RESULTS:The mean age was 67.86±7.25 y and the average interval between two IOL implantations was 645.82±878.44 d.At 1 mo,binocular UCDVA was lower than 0.20 logMAR in 76%of patients(mean 0.12±0.13 logMAR),which increased to 90%by 6 and 12 mo.The binocular UCDVA was significantly better than the monocular results(P<0.05)at 1,6,and 12 mo.Additionally,UCNVA was lower than 0.40 logMAR in 82%of patients,increasing to 90%by 6 and 12 mo.Mean UCNVA in the multifocal IOL implanted eye was statistically significantly better than that in the monofocal IOL implanted eye(P<0.05)at 1,6,and 12 mo.About 5%of patients at 1 and 6 mo,reported"severe glare or halo".Patient satisfaction rates were 95%and 91%at 6 and 12 mo,respectively.CONCLUSION:Unilateral implantation of multifocal IOL in patients with a contralateral,monofocal IOL implantation results in high patient satisfaction rate,with low severe glare or halo rate during follow-up.It can represent a good option for patients who have previously had a monofocal IOL implantation regardless of two year interval duration between two IOL implantations.

Comparison of optical quality after implantable collamer lens implantation and wavefront-guided laser in situ keratomileusis

AIM： To compare the optical quality after implantation of implantable collamer lens（ICL） and wavefront-guided laser in situ keratomileusis（WG-LASIK）.METHODS： The study included 40 eyes of 22 patients with myopia who accepted ICL implantation and 40 eyes of 20 patients with myopia who received WG-LASIK. Before surgery and three months after surgery, the objective scattering index（OSI）, the values of modulation transfer function（MTF） cutoff frequency, Strehl ratio, and the Optical Quality Analysis System（OQAS） values（OVs） were accessed. The higher order aberrations（HOAs） data including coma, trefoil, spherical, 2^（nd） astigmatism and tetrafoil were also obtained. For patients with pupil size 〈6 mm, HOAs data were analyzed for 4 mm-pupil diameter. For patients with pupil size ≥6 mm, HOAs data were calculated for 6 mm-pupil diameter. Visual acuity, refraction, pupil size and intraocular pressures were also recorded.RESULTS： In both ICL and WG-LASIK group, significant improvements in visual acuities were found postoperatively, with a significant reduction in spherical equivalent（P〈 0.001）. After the ICL implantation, the OSI decreasedslightly from 2.34±1.92 to 2.24±1.18 with no statistical significance（P=0.62）. While in WG-LASIK group, the OSI significantly increased from 0.68±0.43 preoperatively to 0.91±0.53 postoperatively（Wilcoxon signed ranks test, P=0.000）. None of the mean MTF cutoff frequency, Strehl ratio, OVs showed statistically significant changes in both ICL and WG-LASIK groups. In the ICL group, there were no statistical differences in the total HOAs for either 4 mmpupil or 6 mm-pupil. In the WG-LASIK group, the HOA parameters increased significantly at 4 mm-pupil. The total ocular HOAs, coma, spherical and 2^（nd） astigmatism were 0.12±0.06, 0.06±0.03, 0.00±0.03, 0.02±0.01, respectively. After the operation, these values were increased into 0.16±0.07, 0.08±0.05,-0.04±0.04, 0.03±0.01 respectively（Wilcoxon signed ranks test, all P〈0.05）. At 6 mm-pupil, the induction of total HOAs was not statistically significant in the WG-LASIK group. CONCLUSION： ICL implantation has a less disturbance to optical quality than WG-LASIK. The OQAS is a valuable complementary measurement to the wavefront aberrometers in evaluating the optical quality.

Comparison of choroidal thickness in high myopic eyes after FS-LASIK versus implantable collamer lens implantation with swept-source optical coherence tomography

AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation using swept-source optical coherence tomography(SS-OCT).METHODS:We examined the right eyes of 116 patients with high myopia who were candidates for FS-LASIK surgery and ICL implantation.Sixty eyes underwent ICL V4c implantation and 56 eyes were subjected to FS-LASIK surgery.The CT was measured with SS-OCT.All data were recorded preoperatively and 2 h,1 wk,1 and 3 mo postoperatively.Other demographic information was collected,including age,sex,uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),spherical equivalent(SE),intraocular pressure(IOP)and axial length(AL).RESULTS:The UCVA improved in both groups and showed no significant differences between groups.There also were no significant differences between the two groups in postoperative BCVA and SE(P=0.581 and 0.203,respectively).The foveal CTs,inner nasal and outer nasal CTs were significantly thicker at 2 h postoperatively in both groups(P<0.05)but returned to baseline levels in 1 wk;after 1 mo,no significant differences were found relative to the preoperative values.At 3 mo in each group,nine regions showed variations in the CT as compared with preoperative thickening,but only the foveal and nasal area CTs preoperative differences were statistically significant(P<0.05).In addition,there was no significant difference in 9 regions of CT between the two groups at all follow-up times(P>0.05).CONCLUSION:The CTs after ICL implantation and FSLASIK surgery are significantly thicker than those before operation,especially in the foveal and nasal areas,but there is no significant difference between the two methods.

Postoperative efficacy,safety,predictability,and visual quality of implantable collamer lens implantation versus small incision lenticule extraction in myopic eyes:a Meta-analysis

AIM:To compare the postoperative efficacy,safety,predictability,and visual quality of implantable collamer lens(ICL)implantation versus small incision lenticule extraction(SMILE)in myopia eyes.METHODS:Pub Med,EMBASE,Web of Science,Cochrane Library and several Chinese databases were searched at May 2021 to select relevant studies in comparison of clinical outcomes between ICL implantation and SMILE for myopia.The primary outcomes were efficacy,safety,and predictability.And the secondary outcomes were postoperative higher-order ocular aberrations(HOAs),modulation transfer function cutoff frequency(MTF),objective scatter index(OSI),contrast sensitivity and a quality of vision(Qo V)questionnaire.RESULTS:A total of 1036 eyes from 10 studies,of which 503 eyes underwent ICL implantation and 533 eyes underwent SMILE,were enrolled in this Meta-analysis.Pooled results revealed that ICL group had a better safety index and post-corrected distance visual acuity(CDVA)(P=0.007,<0.00001,respectively),and a lower percentage of eyes with a postoperative CDVA lost 1 line(P=0.007)than the SMILE group.No significant differences were found in comparison of the other primary outcomes.In the longterm follow-up(>6mo),ICL group had a lower total HOA,coma,and spherical aberration than SMILE group(P=0.003,<0.00001,0.04).Yet higher trefoil was found in ICL group at 6mo after surgery(P=0.003).Additionally,ICL group also had a higher MTF value(P=0.02),and a higher contrast sensitivity score for spatial frequencies of 1.5,6,and 12 cpds(P=0.02,0.005,0.02,respectively).And it also had a lower score of bothersome in Qo V questionnaire than SMILE group(P=0.003).CONCLUSION:ICL implantation and SMILE have similar and comparable outcomes in term of the efficacy and predictability for correcting high myopia.However,ICL group is relatively safer and also has better visual quality in comparison of SMILE group.

A case of hypermature cataract formation following implantation of an implantable collamer lens with an Aquaport

To improve humor circulation the latest V4c Visian implantable collamer lens （ICL） was designed with a0.36-ram Aquapon. This design also eliminates the need to perform peripheral iridectomy before ICL implantation. Several authors reported rates of secondary surgical intervention related to insufficient vault in the presence or absence of cataract formation and excessive vault in the presence or absence of elevated intraocular pressure （IOP） after ICL insertion. Here, we report a case of rapid progression of a cataract to a hypermature state after implantation of an ICL with an Aquaport.

Clinical observations of iridociliary cysts and their changes after implantable collamer lens implantation in myopic patients

AIM:To observe the characteristics of iridociliary cysts in myopic patients and evaluate the influences on the position and safety of implantable collamer lens(ICL)after surgery.METHODS:Totally 270 eyes of 135 patients who underwent ICL surgery for the corrections of myopia were included in this study.Preoperative and postoperative morphology of iridociliary cysts were observed in ultrasonic biomicroscopy(UBM)image.RESULTS:A total of 138 iridociliary cysts were found in 88 eyes of 50 patients among 270 eyes of 135 patients before surgery(37%).Twenty-five patients had cysts in one eye(50%)and 25 had cysts in both eyes(50%).The prevalence of iridociliary cysts was negatively correlated with age,but no gender difference(P>0.05).The incidence of iridociliary cysts was much less in eyes with myopia greater than-9.00 D(P<0.05).The diameter of the largest cyst was 1.96 mm and the smallest cyst was 0.24 mm,with a majority within the range of 0.5 to 1.0 mm.Most of the cysts were located in the inferior temporal quadrant.One year after ICL implantation,51 iridociliary cysts(37%)remained unchanged,47 cysts(34%)decreased in size,and 40 cysts(29%)disappeared.Most of cysts that changed after surgery were smaller than 1.0 mm(P<0.05)and located in the nasal and temporal sides around the haptics of implantable lens.All the ICL were in their original position.CONCLUSION:Iridociliary cysts are commonly seen in myopic eyes.The cysts have no impact on the safety of ICL surgery.Some cysts may decrease in size or disappear after ICL implantation.

Long-term observation on safety and visual quality of implantable collamer lens V4c implantation for myopia correction:a 5-year follow-up

AIM:To elucidate the safety and visual quality of implantable collamer lens with central hole(ICL V4c)implantation for correcting moderate and high myopia for at least 5y.METHODS:This retrospective study was conducted on 58 patients(114 eyes)who were followed up for at least 5y after ICL V4c implantation.The observation was done before and on 1d,1mo,1 and 5y or more after the surgical procedure.The visual acuity,subjective refraction,intraocular pressure,vault,axial length,central hole position,pupil diameter,visual quality,and adverse events were analyzed.The visual quality includes aberration,the modulation transfer function cutoff frequency(MTF cutoff),objective scattering index(OSI),Stroller's ratio(SR),and visual quality questionnaire.RESULTS:The average follow-up period was 69.25±3.80mo(range 60–82mo)and the preoperative spherical equivalent(SE)was-8.66±1.97 D.At 5y after operation,the safety index was 1.01±0.02 and the efficacy index was 0.99±0.42 and SE was-0.65±0.63 D.The 59.6%of the eyes achieved an uncorrected distance visual acuity of 20/20,76.3%of the eyes had SE within±1.0 D at the last visit.The axial length increased by 0.29±0.71 mm 5y after the surgery(t=-3.843,P<0.001).The mean vault at the last follow-up was 510.59±245.61μm.The central hole was on the temporal side in 80 eyes(84.2%).The visual quality questionnaire showed that 98.2%patients were satisfied with the surgical procedure.Adverse events occurred in 4 eyes(3.5%),including the posttraumatic toric ICL rotation(2 eyes),iris incarceration(1 eye),and posttraumatic ICL displacement(1 eye)at the last follow-up.CONCLUSION:Long-term ICL V4c implantation is safe,effective,and stable for correcting moderate and to high myopia,and the visual quality with patients is excellent and satisfactory,but the progression of axial length still needs attention after surgery.

Trocar opening: silicone oil removal with phacoemulsification and intraocular lens implantation

AIM: To evaluate the efficacy and safety of a modified technique [trocar opening(TO)] for silicone oil removal(SOR) in combination with phacoemulsification and intraocular lens(IOL) implantation.METHODS: A total of 60 eyes of 60 patients with cataract and silicone oil-filled eyes were enrolled in this study. The patients were divided into two groups: the patients in the control group underwent 23-gauge pars plana active SOR surgery with phacoemulsification and IOL implantation, while the patients in the TO group underwent TO methods during surgery. Best corrected visual acuity(BCVA), surgery time, intraocular pressure, and operative complications were observed 6 mo after surgery.RESULTS: There was no significant difference between the two groups in terms of age, gender, preoperative, intraocular pressure, or time of silicone oil stay. Prior to surgery, the mean BCVA for the control and TO groups was 1.34±0.44 and 1.36±0.42. At 6 mo following surgery, the mean BCVA improved to 0.74±0.36 and 0.77±0.32, respectively(P<0.001). There was no significant difference between the two groups. The mean SOR time was 6.9±2.3 min and 4.8±1.2 min in the control and TO groups(P=0.008). The total operation time was 28.2±8.5 min and 24.6±6.4 min, respectively(P=0.035). Posterior capsule rupture occurred in four eyes of control and none of TO group(P<0.01). Late recurrent retinal detachment occurred in one eye in the control group(2 mo after surgery) and in one eye in the TO group(4 mo after surgery). CONCLUSION: TO is a simple, effective, time-saving, and safe method for SOR combined with phacoemulsification and IOL implantation.

Full-vision maintenance in extra-high myopia from implantable collamer lens to trifocal intraocular lens implantation

Dear Editor,I am Dr.Ye Shen from the Department of Ophthalmology,the First Affiliated Hospital,College of Medicine,Zhejiang University,Hangzhou,China.I write to share my experience of full-vision maintenance in patient with extrahigh myopia from implantable collamer lens （ICL） to trifocal intraocular lens （IOL） implantation.

The effects of implantable collamer lens implantation on higher order aberrations

AIM: To evaluate the changes in higher order aberrations(HOAs) after implantable collamer lens(ICL;Staar Surgical, Nidau, Switzerland) implantation. METHODS: Totally 30 eyes of 18 patients with myopia were included in this study with an average age of 25.77y(min: 21, max: 40). Refraction, uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), HOAs(entire, corneal and internal) were evaluated preoperatively and three months postoperatively. Ocular aberrations were measured by using iT race(Tracey Technology, Houston, Texas, USA). SPSS(IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp) was used for the statistical analysis and the interpretation of the data. P values of less than 0.05 were considered statistically significant. RESULTS: The preoperative mean spherical power was -9.01 D(min:-5.00, max:-13.00) and the mean cylindrical error was -2.40 D(min:-0.50, max:-4.75). The postoperative mean residual spherical power was -0.73 D(min:-0.20, max:-1.75) and the mean cylindrical error was -0.89 D(min:-0.18, max:-2.09). Analyses were made on root mean square(RMS) values of total HOAs(tH OAs), spherical aberration, coma and trefoil as entire, corneal and internal components. The differences in entire t HOAs and in internal t HOAs were significant. There was no significant change found in spherical aberrations. The differences in entire coma and in internal coma were significant. There was no significant change found in corneal coma. With respect to trefoil, the only significant difference was in internal trefoil. CONCLUSION: The ICL implantation corrects the refractive error successfully and changes entire and internal HOAs of the eye.

Vault predicting after implantable collamer lens implantation using random forest network based on different features in ultrasound biomicroscopy images

AIM:To analyze ultrasound biomicroscopy(UBM)images using random forest network to find new features to make predictions about vault after implantable collamer lens(ICL)implantation.METHODS:A total of 450 UBM images were collected from the Lixiang Eye Hospital to provide the patient’s preoperative parameters as well as the vault of the ICL after implantation.The vault was set as the prediction target,and the input elements were mainly ciliary sulcus shape parameters,which included 6 angular parameters,2 area parameters,and 2 parameters,distance between ciliary sulci,and anterior chamber height.A random forest regression model was applied to predict the vault,with the number of base estimators(n_estimators)of 2000,the maximum tree depth(max_depth)of 17,the number of tree features(max_features)of Auto,and the random state(random_state)of 40.0.RESULTS:Among the parameters selected in this study,the distance between ciliary sulci had a greater importance proportion,reaching 52%before parameter optimization is performed,and other features had less influence,with an importance proportion of about 5%.The importance of the distance between the ciliary sulci increased to 53% after parameter optimization,and the importance of angle 3 and area 1 increased to 5% and 8%respectively,while the importance of the other parameters remained unchanged,and the distance between the ciliary sulci was considered the most important feature.Other features,although they accounted for a relatively small proportion,also had an impact on the vault prediction.After parameter optimization,the best prediction results were obtained,with a predicted mean value of 763.688μm and an actual mean value of 776.9304μm.The R²was 0.4456 and the root mean square error was 201.5166.CONCLUSION:A study based on UBM images using random forest network can be performed for prediction of the vault after ICL implantation and can provide some reference for ICL size selection.