Comparison of Artisan iris-claw intraocular lens implantation and posterior chamber intraocular lens sulcus fixation for aphakic eyes

AIM:To compare the efficacy and complications of Artisan iris-claw intraocular lens(IOL)implantation and posterior chamber IOL sulcus fixation for the treatment of aphakic eyes without capsular support after vitrectomy.METHODS:A prospective study of 45 cases was conducted.Forty-five eyes without sufficient lens capsule support following pars plana vitrectomy(PPV)combined lens extraction were divided into two groups.Group A:25 eyes received Artisan iris-claw IOL implantation.Group B:20 eyes received posterior chamber IOL sulcus fixation.The corrected distance visual acuity(CDVA)and intraocular pressure(IOP),corneal endothelial cell loss rate,surgical time and complications were compared between the two groups.Pigment changes of trabecular meshwork and anterior chamber depths were measured at each time point in Artisan group.RESULTS:The mean surgical time of Artisan group was significantly shorter(P【0.05).No statistically significant difference in endothelial cell loss rate was noted between two groups at any time point(P】0.05).CDVA of Artian group was better than that of the sulcus fixation group 1d after surgery(P【0.05)and there was no statistically significant difference 1 and 3mo after surgery(P】0.05).Mean IOP showed no significant differences between groups before and after surgery.The postoperative complications of Artisan group were anterior uveitis,iris depigmentation,pupillary distortion and spontaneous lens dislocation.The complications of sulcus fixation group include choroidal detachment,intraocular haemorrhage,tilt of IOL optic part and retinal detachment.CONCLUSION:Secondary Artisan IOL implantation canbe performed less invasively and in a shorter surgical time period with earlier visual recovery after surgery compared to transscleral suturing fixation of an IOL.This technique is an effective and safe procedure.It is a promising option for the treatment of aphakic eyes without capsular support after vitrectomy.

Sutured scleral fixation of existing subluxated/dislocated acrylic one-piece intraocular lenses

AIM:To evaluate the visual and refractive outcomes in cases after sutured scleral fixation of existing subluxated or dislocated acrylic one-piece intraocular lenses(IOLs).METHODS:This study retrospectively enrolled a consecutive series of patients who underwent a surgery of sutured existing subluxated or dislocated IOLs from October 2018 to June 2020.All patients underwent comprehensive preoperative and postoperative ophthalmologic examination,and data were collected including age,sex,surgical indications,best-corrected visual acuity,refractive error,intraocular pressure.Presence of intraoperative and postoperative surgical complications was documented.RESULTS:A total of 20 consecutive cases were enrolled for analysis with mean final follow-up period 9.8±5.3mo.Visual acuity improved from a mean of 0.35(0.46±0.32 logMAR)preoperatively to 0.61(0.21±0.18 logMAR)at the 3-month follow-up(P=0.002).The mean amount of preoperative keratometric astigmatism and total postoperative refractive astigmatism was-1.24±0.80 diopters(D)and-1.42±0.97 D,respectively.There was no statistically significant difference between preoperative and postoperative astigmatism(P=0.156).The mean IOL-induced astigmatism was-0.23±0.53 D.The mean spherical equivalent at the 3-month follow-up was-0.1±0.94 D.No major complications were noted during the follow-up period.CONCLUSION:Surgical techniques using sutured scleral fixation of existing subluxated or dislocated acrylic one-piece IOLs result in favorable visual and refractive outcomes without major complications.

Modeling monocular form deprivation in rabbits using a simulated-cataract intraocular lens

AIM:To establish an animal model of form deprivation amblyopia based on a simulated cataract intraocular lens(IOLs).METHODS:Poly(dimethyl siloxane)-SiO_(2) thin films(PSF)with different degrees of opacity as IOL materials were prepared.The light transmission of the PSF-IOL was measured,and its in vitro biosafety was determined by cell counting kit(CCK)-8 assay using the HLEC-B3 cell line and ARPE-19 cell line.Subsequently,the in vivo safety was determined by implanting the PSF-IOL with 10%wt SiO_(2) into the right eyes of New Zealand white rabbits(PSF-IOL group),and compared with two control groups:contralateral comparison group and normal control(NC)group(Contralateral comparison group:the fellow eye;NC group:a group of binocular normal rabbits without intervention).The flash visual-evoked potentials(F-VEPs)were measured to verify amblyopia.RESULTS:PSFs containing 0,2%,and 10%wt SiO_(2) were successfully constructed.The 0 SiO_(2) PSF was transparent,while the 10%wt SiO_(2) PSF was completely opaque.It was found that PSF did not induce unwanted cytotoxicity in HLECs and ARPE19 cells in vitro.In vitro,PSF-IOL with 10%wt SiO_(2) was also non-toxic,and no significant inflammation or structural changes occurred after four weeks of PSF-IOL implantation.Finally,our IOL-simulated congenital cataract rabbit detected by F-VEPs suggested tentative amblyopia.CONCLUSION:A PSF-IOL that mimics cataracts is created.A novel form deprivation model is created by the IOL-simulated congenital cataract rabbit.It can be developed fast and stable and holds great potential for future study.

Biocompatibility of light responsive materials prepared for accommodative intraocular lenses manufacturing

AIM:To investigate the biocompatibility and bacterial adhesion properties of light responsive materials(LRM)and analyze the feasibility and biosafety of employing LRM in the preparation of accommodative intraocular lenses(AIOLs).METHODS:Employing fundamental experimental research techniques,LRM with human lens epithelial cells(hLECs)and human retinal pigment epithelium cells(ARPE-19 cells)were co-cultured.Commercially available intraocular lenses(IOLs)were used as controls to perform cell counting kit-8(CCK-8),cell staining under varying light intensities,cell adhesion and bacterial adhesion experiments.RESULTS:LRM exhibited a stronger inhibitory effect on the proliferation of ARPE19 cells than commercially available IOLs when co-cultured with the undiluted extract for 96h(P<0.05).Under other culturing conditions,the effects on the proliferation of hLECs and ARPE-19 cells were not significantly different between the two materials.Under the influence of light irradiation at intensities of 200 and 300 mW/cm^(2),LRM demonstrated a markedly higher inhibitory effect on the survival of hLECs compared to commercially available IOLs(P<0.0001).They also showed a stronger suppressive effect on the survival rate of ARPE-19 cells,with significant differences observed at 200 mW/cm^(2)(P<0.001)and extremely significant differences at 300 mW/cm^(2)(P<0.0001).Additionally,compared to commercially available IOLs,LRM had a higher number of cells adhering to their surface(P<0.05),as well as a significantly greater number of adherent bacterium(P<0.0001).CONCLUSION:LRM,characterized by their excellent non-contact tunable deformability and low cytotoxicity to ocular tissues,show considerable potential for use in the fabrication of AIOLs.These materials demonstrate strong cell adhesion;however,during photothermal conversion processes involving shape deformation under various light intensities,the resultant temperature rise may harm surrounding cells.These factors suggest that while the material plays a positive role in reducing the incidence of posterior capsule opacification(PCO),it also poses potential risks for retinal damage.Additionally,the strong bacterial adhesion of these materials indicates an increased risk of endophthalmitis.

Intraocular lens selection in diabetic patients:How to increase the odds for success

The incidence of cataracts is significantly higher in diabetic individuals,particularly in younger age groups,with rates quadrupled in those under 65 and doubled in those over 65 compared to non-diabetics.Cataract surgery in diabetic patients poses many challenges:Poor epithelial healing,decreased corneal sensitivity,increased central corneal thickness,decreased endothelial cell count,variable topography,poor pupillary dilatation,anterior capsular phimosis,posterior capsular opacification(PCO),chances of progression of diabetic retinopathy(DR),zonular weakness,and vitreous prolapse and diabetic macular edema.Selection of an appropriate intraocular lens(IOL)is crucial for visual rehabilitation and monitoring DR.The choice of IOL in diabetic cataract patients is a challenging scenario.Square-edge IOLs are favored for their capacity to mitigate PCO,whereas hydrophilic counterparts may incur calcification in the setting of proliferative DR.The advisability of premium IOLs for achieving spectacle independence warrants judicious evaluation,particularly in the presence of advanced retinopathy.Optimal IOL placement within the capsular bag is advocated to minimize postoperative complications.Rigorous preoperative assessment and informed patient counseling regarding IOL options are indispensable for optimizing surgical outcomes.This review article covers various aspects regarding the choice of IOLs in different case scenarios and complications in the diabetic population.

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.

Optical biometry intraocular lens power calculation using different formulas in patients with different axial lengths

AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were included who underwent uneventful phacoemulsification with IOL implantation in the Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan, China from February 2007 to January 2009. Preoperative AL and keratometric values (Ks) were measured by IOLMaster optical biometry. Patients were divided into 3 groups based on AL less than 22mm (Group 1), 22-26mm (Group 2), and more than 26mm (Group 3). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: the Haigis, Hoffer Q, Holladay 1, and SRK/T. The predictive accuracy of each formula was analyzed by comparing the difference between the actual and predicted postoperative SE (MedAE, median absolute error). All the patients had follow-up periods exceeding 3 months. RESULTS: Totally, there were 200 eyes (33 eyes in Group 1, 92 eyes in Group 2, 75 eyes in Group 3). In all patients, the Haigis had the significantly lower MedAE generated by the other formulas (P【0.05). In Group 1 to 3, the MedAE calculated by the Haigis was either significantly lower or comparable to those calculated by the other formulas.CONCLUSION: Compared with other formulas using IOLMaster biometric data, the Haigis formula yields superior refractive results in eyes with various AL.

Long-term vision-threatening complications of phakic intraocular lens implantation for high myopia

AIMTo report the long-term vision-threatening complications in patients who underwent phakic intraocular lens (pIOLs) implantation for high myopia.

High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric,aberration correcting monofocal intraocular lens

·AIM: To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting,monofocal intraocular lens(IOL).·METHODS: Twenty-one patients(34 eyes) aged 50 to83 y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL(Tecnis ZCB00,Abbott Medical Optics). Three months after surgery they were examined for uncorrected(UDVA) and corrected distance visual acuity(CDVA), contrast sensitivity(CS)under photopic and mesopic conditions with and without glare source, ocular high order aberrations(HOA, Zywave II) and retinal straylight(C-Quant).· RESULTS: Postoperatively, patients achieved a postoperative CDVA of 0.0 log MAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27(primary coma components) and-0.04 ±0.16(spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed(P ≥0.28).· CONCLUSION: The implantation of an aspherical aberration correcting monofocal IOL after cataractsurgery resulted in very low residual higher order aberration(HOA) and normal straylight.

Predictive factors for photic phenomena after refractive,rotationally asymmetric,multifocal intraocular lens implantation

AIM： To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses（MIOLs）.METHODS： Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS： The distance from the photopic to the mesopic pupil center（pupil center shift） was significantly associated with glare/halo symptoms [odds ratio（OR）=2.065,95% confidence interval（CI）=0.916-4.679,P=0.006] and night vision problems（OR=1.832,95% CI=0.721-2.158,P=0.007）.The preoperative photopic angle kappa was significantly associated with glare/halo symptoms（OR=2.155,95% CI=1.065-4.362,P=0.041）.The photopic angle kappa was also significantly associated with glare/halo symptoms（OR=2.155,95% CI=1.065-4.362,P=0.041） and with night vision problems（OR=1.832,95% CI=0.721-2.158,P=0.007） in patients implanted with rotationally asymmetric MIOLs.CONCLUSION： A large pupil center shift and misalignment between the visual and pupillary axis（angle kappa）may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs.

Effect of lens constants optimization on the accuracy of intraocular lens power calculation formulas for highly myopic eyes

AIM: To evaluate the effect of different lens constant optimization methods on the accuracy of intraocular lens(IOL) power calculation formulas for highly myopic eyes.METHODS: This study comprised 108 eyes of 94 consecutive patients with axial length(AL) over 26 mm undergoing phacoemulsification and implantation of a Rayner(Hove, UK) 920H IOL. Formulas were evaluated using the following lens constants: manufacturer’s lens constant, User Group for Laser Interference Biometry(ULIB) constant, and optimized constant for long eyes. Results were compared with Barrett Universal II formula, original Wang-Koch AL adjustment method, and modified Wang-Koch AL adjustment method. The outcomes assessed were mean absolute error(MAE) and percentage of eyes with IOL prediction errors within ±0.25, ±0.50, and ±1.0 diopter(D). The nonparametric method, Friedman test, was used to compare MAE performance among constants.RESULTS: Optimized constants could significantly reduce the MAE of SRK/T, Hoffer Q, and Holladay 1 formulas compared with manufacturer’s lens constant, whereas the percentage of eyes with IOL prediction errors within ±0.25, ±0.50, and ±1.0 D had no statistically significant differences. Optimized lens constant for long eyes alone showed non-significant refractive advantages over the ULIB constant. Barrett Universal II formula and formulas with AL adjustment showed significantly higher accuracy in highly myopic eyes(P<0.001). CONCLUSION: Lens constant optimization for the subset of long eyes reduces the refractive error only to a limited extent for highly myopic eyes.

Clinical study of customized aspherical intraocular lens implants

AIM:To compare if there is an improvement in visual functions with age-related cataracts between patients receiving a aspherical intraocular lens(IOL) based on corneal wavefront aberration and patients randomly assigned lenses.METHODS:A total of 124 eyes of 124 patients with age-related cataracts were placed in experimental group and a group receiving randomly assigned(RA) lenses.The experimental group was undergone Pentacam corneal spherical aberration measurement before surgery; the targeted range for residual total spherical aberration after surgery was set to 0-0.3 μm. Patients with a corneal spherical aberration 【0.3 μm were implanted with a zero-spherical aberration advanced optics(AO) aspherical IOL and patients with an aberration ≥0.3 μm received a Tecnis Z9003 aspherical lens in experimental group. RA patients were randomly implanted with an AO lens or a Tecnis Z9003 lens. Three months after surgery total spherical aberration, photopic/mesopic contrast sensitivities, photopic/mesopic with glare contrast sensitivities, and logMAR vision were measured.RESULTS:Statistical analysis on logMAR vision showed no significant difference between two groups(P =0.413). The post-surgical total spherical aberration was 0.126 ±0.097 μm and 0.152 ±0.151 μm in the experimental and RA groups, respectively(P =0.12). The mesopic contrast sensitivities at spatial frequencies of 6,12 and 18 c/d in the experimental group were significantly higher than of the RA group(P =0.00; P =0.04;P =0.02). The mesopic with glare contrast sensitivity in the experimental group at a spatial frequency of 18 c/d was also significantly higher vs the RA group(P =0.01).CONCLUSION:Pre-surgical corneal spherical aberration measurement in cataract patients followed bycustomized selection of aspherical IOL implants improved mesopic contrast sensitivities at high spatial frequencies, and thus is a superior strategy compared to the random selection of aspherical intraocular lens implants.

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.

Postoperative visual performance with a bifocal and trifocal diffractive intraocular lens during a 1-year follow-up

AIM：To evaluate and compare the clinical outcomes with a diffractive bifocal and trifocal intraocular lens（IOL）during a 12-month follow-up.METHODS：Prospective comparative study including75 eyes of 38 patients（44-70y）undergoing uneventful cataract surgery.Each patient was randomly assigned to one type of IOL,bifocal（35 eyes）or trifocal（40 eyes）.Visual,refractive,and contrast sensitivity changes were evaluated in a 12-month follow-up.The binocular defocus curve was also measured at 12mo postoperatively.RESULTS：No statistically significant differences between groups were found in postoperative uncorrected and corrected distance visual acuities（P≥0.276）.Postoperative corrected near visual acuity（33 cm）was significantly better in the trifocal group during all follow-up（P≤0.004）as well as 6-month uncorrected near（P=0.008）and distancecorrected near visual acuities（P=0.016）（33/40 cm）.Significantly better uncorrected intermediate and distance corrected-intermediate visual acuity were found during all follow-up in the trifocal group（P〈0.001）,which was consistent with differences among groups in binocular defocus curve.Differences among groups in contrast sensitivity were minimal,being only significant at 6 months for some low to medium spatial frequencies（P≤0.006）.CONCLUSION：Bifocal and trifocal diffractive IOLs are able to provide an effective visual restoration which is maintained during a 12-month follow-up,with a clear benefit of the trifocal IOL for the intermediate vision.

Comparison of visual outcomes with implantation of trifocal versus bifocal intraocular lens after phacoemulsification: a Meta-analysis

AIM： To compare a trifocal intraocular lens （IOL） and a bifocal IOL implantation in improving visual function after cataract surgery. METHODS： Eligible literatures were systematically searched through EMBASE and PubMed databases. The inclusion criteria were prospective comparative clinical trials on cataract surgery comparing trifocal IOL with bifocal IOL implantation that assessed visual acuity, contrast sensitivity and subjective vision quality. The effects were computed as standardized mean differences and pooled using fixed-effect or random-effect models. RESULTS： Four prospective randomized controlled trials （RCTs） and five cohorts provided data were included by a systematic review, comprising 265 eyes implanted with trifocal IOLs and 264 eyes implanted with bifocal IOLs. Monocular distance visual acuity （VA） showed a statistically significant but small difference that favored trifocal IOLs （MD=.0.06; 95%CI, -0.10 to -0.02; Z=2.90, P=0.004 for uncorrected distance VA, and MD- -0.02; 95%CI, -0.03 to .0.00; Z=2.02, P=0.04 for corrected distance VA）, but the data did not suggest that the effect of trifocal IOL implantation would clinically outperform bifocal IOL implantation. There was no significant difference in monocular near VA （MD=.0.01; 95%CI, -0.07 to 0.04; Z=0.42, P=-0.68 for distance-corrected near VA, and MD=-0.01; 95%CI, -0.06 to 0.03; Z=0.55, P=0.58 for corrected near VA） or refraction between two groups. Contrast sensitivity and subjective visual quality had no conclusive results. CONCLUSION： All results indicate that trifocal IOL and bifocal IOL had similar levels of monocular distance and near VA.

Visual function and higher order aberration after implantation of aspheric and spherical multifocal intraocular lenses:a meta-analysis

AIMTo assess the visual outcomes of aspheric multifocal intraocular lenses (IOLs) compared with spherical multifocal IOL after cataract surgery.

Visual and optical performance of eyes with different corneal spherical aberration implanted with aspheric intraocular lens

AIM: To compare the visual and optical performance of eyes with different corneal spherical aberration (SA) implanted with spherical aberration-free intraocular lens (IOLs). METHODS: Thirty-six patients with different corneal SA had phacoemulsification with implantation of spherical aberration-free IOLs. Patients were divided into 3 groups according to the value of preoperative corneal SA. Eyes with corneal SA <0.10 mu m were assigned to group A, those with 0.10 <= corneal SA <0.20 mu m to Group B, and those with 0.20 <= corneal SA <0.35 mu m to Group C. Best-corrected visual acuity (BCVA), contrast sensitivity, corneal SA, total ocular aberrations, and depth of focus were recorded 3 months postoperatively. Distance-corrected near and intermediate visual acuity was studied to measure depth of focus. RESULTS: BCVA and contrast sensitivity were similar between groups. There were no significant differences in distance-corrected near or intermediate visual acuity. Corneal SA was similar before and 3 months after surgery in the 3 groups. With a 5.0mm pupil diameter, root mean square values for total ocular higher-order aberrations (HOAs) were lower in groups A and B than in group C. Total ocular SA was lower in group A than in groups B and C. SA was also lower in group B than in group C. Coma and trefoil were similar between the groups. CONCLUSION: Implantation of spherical aberration-free IOLs in eyes with different corneal SA results in similar visual performance at BCVA, contrast sensitivity and depth of focus.

Optical quality of toric intraocular lens implantation in cataract surgery

AIM: To analyze the optical quality after implantation of toric intraocular lens with optical quality analysis system.METHODS: Fifty-two eyes of forty-four patients with regular corneal astigmatism of at least 1.00 D underwent implantation of Acry Sof toric intraocular lens, including T3 group 19 eyes, T4 group 18 eyes, T5 group 10 eyes,T6 group 5 eyes. Main outcomes evaluated at 3mo of follow-up, included uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), residual refractive cylinder and intraocular lens(IOL) axis rotation.Objective optical quality were measured using optical quality analysis system(OQAS Ⅱ, Visiometrics, Spain),included the cutoff frequency of modulation transfer function(MTFcutoff), objective scattering index(OSI),Strehl ratio, optical quality analysis system value(OV)100%, OV 20% and OV 9% [the optical quality analysis system(OQAS) values at contrasts of 100%, 20%, and 9%].RESULTS: At 3mo postoperative, the mean UDVA and CDVA was 0.18 ±0.11 and 0.07 ±0.08 log MAR; the mean residual refractive cylinder was 0.50 ±0.29 D; the mean toric IOL axis rotation was 3.62 ±1.76 degrees, the mean MTFcutoff, OSI, Strehl ratio, OV 100%, OV 20% and OV9% were 22.862 ±5.584, 1.80 ±0.84, 0.155 ±0.038, 0.76 ±0.18,0.77±0.19 and 0.78±0.21. The values of UDVA, CDVA, IOL axis rotation, MTFcutoff, OSI, Strehl ratio, OV100%,OV20% and OV9% depending on the power of the cylinder of the implantation were not significantly different(P 】0.05), except the residual refractive cylinder(P 【0.05).CONCLUSION: The optical quality analysis system was useful for characterizing the optical quality of Acry Sof toric IOL implantation. Implantation of an Acry Sof toric IOL is an effective and safe method to correct corneal astigmatism during cataract surgery.

Intraocular lens optic capture in pediatric cataract surgery

Posterior capsule opacification（PCO） remains the most common complication of pediatric cataract surgery despite continuous efforts to reduce its incidence. For this reason, pediatric cataract surgeons have expended considerable effort into preventing and mitigating PCO. The intraocular lens（IOL） optic capture technique has been used for the prevention of PCO after pediatric cataract surgery for more than 20 y, but there is still no professional consensus. However, recent research has shown encouraging results. The IOL optic capture technique can be performed without anterior vitrectomy to prevent PCO, even in younger children. The type and characteristics of IOLs used for optic capture technique, the location of IOL and the complications of IOL optic capture in children are here reviewed.

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.