Intracapsular Intraocular Lens Research Articles

Comparison of IOL power formulas in eyes with a flat cornea

PurposeTo assess and compare accuracy of intraocular lens (IOL) power calculation performed with old generation, new generation and artificial intelligence (AI)-based formulas in eyes with flat corneas. DesignPatients with a tomography-derived mean keratometry <42 D were retrospectively recruited among those who underwent uncomplicated phacoemulsification with intracapsular IOL implantation in two different tertiary care centers. Mean prediction error (ME), mean absolute prediction error (MAE) and incidence of MAE>0.25D were calculated for Barrett Universal II (BUII),EVO 2.0, Hoffer QST, Kane, Olsen-C, Pearl-DGS and SRK/T formulas. Linear correlation between MAE and axial length was also calculated for each formula. ResultsEighty (80) eyes with a mean keratometry of 41.4 ± 0.6 D (range 40.6–41.9 D) were recruited. The SRK/T significantly differed from both the Olsen-C (p = 0.022) and the BUII (p = 0.048) in ME. The EVO 2.0, the Hoffer QST, the Kane and the PEARL-DGS showed a significantly lower MAE compared to all other formulas (p < 0.001) and a significant lower incidence of MAE>0.25D (p < 0.001), MAE>0.50 D (p < 0.001) and MAE>1.0 D (0.002). ConclusionFormulas based on AI and on the theory of vergence show superior accuracy in IOL power calculation in corneas with low mean keratometry; their MAE is not correlated to axial length.

Outcomes of Secondary Intracapsular Intraocular Lens Implantation in Patients following Rhegmatogenous Retinal Detachment.

This study reports the outcomes of a secondary IOL implantation technique in patients that suffered from rhegmatogenous retinal detachment combined with a cataract, which included reopening the capsular bag, enabling secondary intracapsular intraocular lens (IOL) implantation. We included consecutive cases with rhegmatogenous retinal detachment (RRD) treated with vitrectomy and silicone oil tamponade, and subsequent secondary IOL implantation during silicone oil removal between September 2019 and June 2022. Demographics, pre- and postoperative clinical data, and complications were collected. Visual and refractive outcomes and IOL position were evaluated. Thirty eyes were included and followed up for a mean of 24.2 ± 5.06 months. Compared with the preoperative values, no significant changes were observed in the intraocular pressure (p = 0.170) and endothelial cell density (p = 0.336); however, the best-corrected visual acuity (Snellen: 20/83 vs. 20/38; logMAR: 0.66 ± 0.23 vs. 0.37 ± 0.32; p < 0.001) and spherical equivalent (p < 0.001) improved significantly. The mean prediction error (ME) was -0.45 ± 0.68 D (-1.9-0.54 D), and the mean absolute prediction error (MAE) was 0.62 ± 0.52 D (0.01-1.9 D). The macula-on subgroup demonstrated significantly better refractive outcomes than the macula-off subgroup (ME, p = 0.046; MAE, p = 0.008). The IOL was well positioned, with a mean horizontal and vertical tilt and decentration of 0.53 ± 0.49° and 0.21 ± 0.16 mm, and 0.54 ± 0.45° and 0.22 ± 0.16 mm, respectively. Secondary intracapsular IOL implantation provided a good and stable IOL position and satisfactory refractive outcomes, and is a feasible treatment option for patients with RRD.

Phaco surgery in disorders of the capsular-zonular apparatus of the lens

The article presents authors' original methods of phaco surgery that can be used in disorders of the capsular-zonular apparatus of the lens. The cataract surgery techniques for lens subluxation developed and introduced into clinical practice allow using the most physiologically correct intracapsular intraocular lens (IOL) fixation in the vast majority of cases. The introduction of femtosecond laser at key stages of phacoemulsification in complicated clinical situations reduces the dependence of the results on the human factor and allows performing removal of complicated cataracts at a qualitatively new level.

Automated Precision Pulse Capsulotomy Versus Manual Capsulorhexis In White Cataracts: Reduction In Procedural Time And Resource Utilization.

To compare the utility of Precision Pulse Capsulotomy (PPC) with manual capsulorhexis for capsulotomy in white cataracts. Hospital-based academic practice. Retrospective analysis of surgical case records and surgical videos from a single surgeon. Cases involving intumescent and non-intumescent white cataracts were identified. Capsulotomy outcomes, surgical outcomes, procedural time, and resource utilization as well as patient demographic and health data were analyzed and subjected to statistical testing. 15 cases of white cataract (10 Intumescent, 5 non-intumescent) performed using Continuous Curvilinear Capsulorhexis (CCC) were compared to 20 cases (9 Intumescent, 11 non-intumescent) performed using PPC. The cases covered a period of 14 months prior to and 30 months following surgeon adoption of PPC. There were no significant differences between the 2 groups in subject age, sex, ethnicity, ocular history, medical history and medications. PPC resulted in complete capsulotomies without tags or tears and intracapsular IOL implantation with 360-degree capsular overlap in all 20 cases. There was one CCC case resulting in the Argentinian Flag sign. Compared to CCC, PPC white cataract cases also demonstrated significant advantages in capsulotomy time, reduced use of trypan blue and ophthalmic viscosurgical device (OVD), and less overall procedural time. PPC is a safe and highly effective method to create consistent capsulotomies in both intumescent and non-intumescent white cataracts. The use of PPC provides benefits of significant reductions in capsulotomy time, overall procedural time and resource utilization resulting in a streamlined treatment of these complex cataract surgery cases.

Surgical treatment of hypermature cataract in patients with lens subluxation and small pupil

To develop a technique for hybrid (femtosecond laser-assisted) phacoemulsification in patients with a combination of hypermature cataract, small pupil and lens subluxation. Hybrid (femtosecond laser-assisted) phacoemulsification of hypermature cataracts was performed in 36 patients (36 eyes) aged 63 to 78 years with grade I-II lens subluxation in combination with small pupil. The initial circular femtolaser capsulotomy was performed within the small pupil using the VICTUS system (Technolas Perfect Vision, Germany). After dilating the pupil with retractor hooks, the capsulorhexis was manually expanded to the required diameter. In all cases, the resulting capsulorhexis had a regular round shape with a smooth edge, without radial ruptures. This made it possible to apply modern methods of fixation and centration of the capsular bag in case of lens subluxation and to perform intracapsular implantation of an intraocular lens (IOL). Complete intracapsular fixation of the IOL with optics edge fully covered by the edge of the capsulorhexis in the postoperative period was achieved in 34 (94.4%) cases. In 2 (5.6%) cases in the postoperative period, the edge of the capsulorhexis exceeded the edge of the IOL optics. The loss of corneal endothelial cells 3 months after surgery was 8.8±1.9%. The use of the proposed combined technique of capsulorhexis made it possible to perform the most physiologically appropriate intracapsular IOL implantation in all patients with hypermature cataract, small pupil and lens subluxation.

Weighted Comparison of the Corneal Topographic Data in Intracapsular versus Ciliary Sulcus Intraocular Lens Implantation during Phacoemulsification Surgery.

Objectives:This study aimed to evaluate the preoperative and postoperative changes in corneal topography, intraocular pressure (IOP), and visual acuity in patients who developed posterior capsule rupture during phacoemulsification surgery and simultaneously underwent ciliary sulcus intraocular lens (IOL) implantation and in those with intact capsular integrity who simultaneously underwent intracapsular IOL implantation and to compare these changes within and between the two groups.Methods:Among the 855 patients, 92 eyes of 69 patients whose corneal topography, IOP, and best-corrected visual acuity (BCVA) were successfully measured were included in the study. Preliminary chamber parameters [horizontal visible iris diameter (HVID), iridocorneal angle, anterior chamber volume (ACV), and anterior chamber depth (ACD)] were measured before and after surgery using a Sirius corneal topography device.Results:The IOL was implanted in the capsular bag in 58 patients and in the ciliary sulcus between the posterior iris and the capsule in 34 patients. In the sulcus IOL group, both BCVA and IOP measurements statistically significantly increased in the postoperative period compared with the preoperative values (p<0.001). As regards postoperative changes between the intracapsular and sulcus IOL groups, no significant difference was found in the changes in HVID (p=0.584), iridocorneal angle (p=0.282), and ACD (p=0.382), whereas the changes in ACV, IOP, and BCVA were statistically significantly different (p=0.020, p<0.001, and p<0.001, respectively).Conclusion:While the IOP of the sulcus IOL group significantly increased, that of the intracapsular group significantly decreased. Visual acuity increased in both lens implants, but patients with intracapsular lenses had greater improvement in visual acuity; thus, intracapsular IOL implantation was more advantageous than sulcus IOL implantation.

Precision pulse capsulotomy in challenging cataract surgery cases.

PurposeTo evaluate the use of the precision pulse capsulotomy (PPC) device for challenging cataract surgery cases.Patients and methodsThis single-center retrospective case series study comprised of 43 eyes (from 35 patients) that were challenging cataract surgery cases with poorly dilated pupils, anterior subcapsular opacity, white cataract, brunescent cataract, and corneal opacity. This was conducted at the Busan Sungmo Eye Hospital (Busan, Republic of Korea) to assess the performance of the PPC device through a 2.2-mm clear corneal incision width, followed by the phacoemulsification technique and intracapsular intraocular lens fixation. The main outcome measurement was the anterior capsulotomy performance of the PPC device and the development of intraoperative complications. At postoperative 2 months, visual acuity, endothelial cell count, and refractive error were measured.ResultsNo cases of anterior capsule tears or tags occurred. All 43 eyes received circular, 360-degree, free-floating, and appropriately sized anterior capsulotomies. During 2 months of follow up, no postoperative complications occurred in association with the PPC device.ConclusionThe PPC device facilitated the creation of a precise, round, appropriately sized anterior capsulotomy in challenging cataract surgery cases. Further investigations are required to understand the long-term safety and efficacy of the PPC device.

Precision pulse capsulotomy in phacoemulsification: Clinical experience in Indian eyes.

Purpose:To evaluate the surgical outcome of precision pulse capsulotomy (PPC) in phacoemulsification surgery.Methods:One hundred twenty-three eyes of 99 consecutive patients who underwent phacoemulsification with PPC through a 2.8 mm clear corneal incision were prospectively studied at a tertiary care centre. The size, shape of capsulotomy and intraoperative capsulotomy, and surgery-related complications were noted. Visual outcome, IOL stability, and signs of capsular opacification/contraction were evaluated at 3 and 6 months.Results:The mean age of patients was 49.5 ± 7.77 years. Complete, circular capsulotomy averaging 5.5 mm diameter was achieved in 117 of 123 eyes. In seven eyes, we experienced complications like capsulorhexis tear (n = 6) and inadvertent iris capture (n = 1). Probe malfunction occurred in six cases. Stable intracapsular intraocular lens (IOLs) fixation and centration was achieved in all eyes. None of the eyes had any significant posterior capsular opacification or capsular contraction at 3 and 6 months. In one eye anterior capsular opacification at the capsulotomy edge was noted at 6 months.Conclusion:PPC is a useful device for achieving a perfectly round capsulorrhexis. However, it has a learning curve and chances of skip areas in capsulorhexis, capsular tag, and its extension should be kept in mind. Special care should be taken in initial cases and while operating on eyes with poorly dilating pupil and mature cataracts.

Phacoemulsification combined with transpupillary removal of silicone oil and intracapsular intraocular lens implantation

To estimate the effectiveness of phacoemulsification and foldable intraocular lens (IOL) implantation combined with transpupillary silicone oil removal. There were 168 eyes of 168 candidate patients with cataract and silicone oil-filled eyes recruited in our study. All of the patients received the intraocular silicone oil removal surgery by transpupillary drainage and cataract extraction by phacoemulsification. Then the IOL implantation were also performed through corneal incision. The surgery was successfully completed in all eyes. Best corrected visual acuity (BCVA) and postoperative complications were recorded in three months after surgery. There were 143 eyes with BCVA improved, otherwise 25 eyes remained stable at the last follow-up visit. The mean BCVA statistically improved from 20/400±0.02 to 20/100±0.15 (P<0.001) and mean postoperative IOP was 13.85±2.18 mm Hg (P=0.415). No intra-operative complications were reported. Phacoemulsification combined with transpupillary removal of silicone oil is a safe and simple effective method. In general, it enables quick recovery of visual acuity with less complication rate.

Intraocular lens exchange surgery at a tertiary referral center: Indications, complications, and visual outcomes

To identify indications for and visual outcomes of intraocular lens (IOL) exchange to understand recent changes in this surgery. Academic tertiary referral center. Retrospective case series. Cases were identified by searching the institution's electronic medical records from January 2010 to September 2015 for patients treated by 1 staff physician with the American Medical Association's Current Procedural Terminology code for IOL exchange. These cases were reviewed to determine the surgical indication, type of IOL removed, type of IOL implanted, time between surgeries, surgical complications, and visual outcomes. The study comprised medical records of 109 eyes. The mean time between the primary cataract surgery and IOL exchange was 1657days. Dislocation of an in-the-bag posterior chamber IOL (27.5%), intolerance of a multifocal IOL (18.3%), and uveitis-glaucoma-hyphema syndrome (11.9%) were the most frequent indications for IOL exchange. The final IOL position after exchange was most frequently in the capsular bag (43.1%), anterior chamber (25.7%), or sulcus(22%). The final visual acuity at 1month was 20/40 or better in 78.9% of cases. Of those not achieving this level of acuity, pathology not related to exchange surgery was identified in 48% of cases. The most frequent complications after IOL exchange surgery were posterior capsule opacification (13.8%), cystoid macular edema (10.1%), and high astigmatism (>1.5 diopters) (8.3%). The most frequent indication for IOL exchange surgery was dislocated IOLs; the second most frequent indication was patient dissatisfaction after multifocal IOL implantation. The increased ability to place an intracapsular IOL with few intraoperative complications and largely treatable postoperative complications enhances the effectiveness of IOL exchange surgery and patient satisfaction. Neither author has a financial or proprietary interest in any material or method mentioned.

Evaluation of central corneal thickness after cataract surgery, penetrating keratoplasty and long-term soft contact lens wear

The aim of this study was to compare central corneal thickness (CCT) between corneas of normal healthy eyes (cNHE), corneas of eyes that had undergone cataract surgery by clear corneal phacoemulsification with implantation of an intracapsular intraocular lens (cIOL), corneal grafts after penetrating keratoplasty (gPK) and corneas of long-term soft contact lens wearers (cCL). The study design was a consecutive cross-sectional trial. CCT was measured using rotating Scheimpflug camera (Pentacam, software version 1.16r04) in 80 cNHE, 79 cIOL, 46 gPK and 78 cCL. Analysis of variance (one-way ANOVA) was performed to compare differences of mean values between these four groups. Pearson's or Spearman's correlation coefficient (r) was determined between CCT value and age, follow up time after penetrating keratoplasty (timePK) or contact lens wearing time (timeCL). Means of CCT measurements were comparable between cNHE (mean CCT±standard deviation, 554±36μm), cIOL (551±40μm) and gPK (534±52μm) as determined by one-way ANOVA. Mean CCT values in cCL (537±37μm) were statistically significantly lower in comparison to cNHE (p=0.026, 95% CI=1.43-31.44). There was no linear correlation between age and CCT values of cNHE and cIOL (p=0.841, r=-0.031 and p=0.931, r=0.011, respectively). No linear relationship was determined between CCT values of cCL and timeCL (p=0.315, r=-0.125). CCT values of gPK did not correlate with timePK (p=0.738, r=0.054). The data reported here indicate that in the same statistical model among CCT values of cNHE, cIOL and gPK only long-term soft contact lenses (CL) wearer have significantly lower CCT measurements.

Sutureless Phacoemulsification With Transpupillary Removal of Silicone Oil and Intracapsular Intraocular Lens Implantation Using Illuminated 23-Gauge Infusion System

Sutureless Phacoemulsification With Transpupillary Removal of Silicone Oil and Intracapsular Intraocular Lens Implantation Using Illuminated 23-Gauge Infusion System

The preventive effect of capsular tension ring in phacoemulsification of senile cataracts with pseudoexfoliation

We evaluated the preventive role of the capsular tension ring (CTR) in zonular and capsular complications in the phacoemulsification surgery of cataracts with pseudoexfoliation (PEX) in two groups of eyes with senile cataract associated with PEX, with (Group A) or without (Group B) CTR implantation. CTR implantation did not prove as effective as expected in preventing the zonulo-capsular complications. Contradictory to the significant increase of intracapsular intraocular lens (IOL) implantation rate, post-operative visual acuity did not improve in the same value.

Stenotrophomonas maltophilia Endophthalmitis after Cataract Extraction

Purpose: To report the clinical course, treatment response, and prognosis of Stenotrophomonas maltophilia endophthalmitis following cataract extraction. Methods: The clinical records of six cases of S. maltophilia endophthalmitis after cataract extraction were retrospectively reviewed. Data were collected for surgical characteristics, disease course, culture growth, antibiotic sensitivity of the pathogen, response to treatment, and final visual acuity. Results: Four patients underwent uncomplicated cataract extraction with phacoemulsification (PHACO) and intracapsular intraocular lens (IOL) implantation. One case was complicated by inadvertent posterior capsular tear during PHACO and IOL implantation. One patient underwent a combined extracapsular cataract extraction (ECCE) with IOL implantation and trabeculectomy, but vitrectomy was also performed because of cortical material loss into the vitreous cavity after a capsular tear. Symptoms began between postoperative days 1 and 19. All patients underwent a vitreous tap and intravitreal injections of antibiotics. Medical therapy alone was sufficient in five patients to treat the infection. One patient had four episodes of recurrence. Pars plana vitrectomy with subsequent capsulectomy and IOL extraction were performed in this patient to complete remission. Conclusion: S. maltophilia should be considered a pathogenic organism possibly causing endophthalmitis after PHACO+IOL implantation. The clinical picture resembles acute bacterial endophthalmitis. When the pathogen has settled in the capsular bag, the infection may persist and become refractory to medical treatment.

Early postoperative capsular block syndrome related to saccadic-eye-movement-induced fluid flow into the capsular bag

PurposeTo determine the relationship between saccadic eye movements and the development of early postoperative capsular block syndrome. SettingFundacion Oftalmologica, Los Andes, Santiago, Chile. MethodsAn artificial experimental setup was designed to reproduce the anatomical, hydrodynamic, and kinetic conditions of an early postoperative pseudophakic eye with a capsulorhexis and intracapsular intraocular lens (IOL) implantation. An electromechanical transducer driven by a digital-to-analog converter was used to mimic saccadic eye movements at physiological speeds and accelerations. Position information and differential pressure measurements between the intracapsular space and the extracapsular space were digitized. Various anterior capsule–IOL configurations were tested including partial adhesion of the anterior capsule to the lens. ResultsSaccadic movements increased intracapsular pressure by displacing fluid into the capsular bag. This finding was inconstant and only observed when the capsular rim adhered to the IOL optic by more than 70%. Development of positive intracapsular pressure was noted above 4 mm Hg. ConclusionA valve-like mechanism formed by the capsulorhexis rim partially adhered to the IOL optic can occur postoperatively. Under these conditions, saccadic eye movements can increase intracapsular pressure by a unidirectional inertial displacement of fluid into the capsular bag.

Delayed intraocular lens dislocation after neodymium:YAG capsulotomy

A poly(methyl methacrylate) (PMMA) intraocular lens (IOL) disocated into the vitreous cavity in 2 patients after a neodymium:YAG (Nd:YAG) laser posterior capsulotomy. In Case 1, the capsulotomy was performed 19 months after extracapsular cataract extraction (ECCE) and sulcus fixation of an IOL. Six months later the IOL dislocated posteriorly. In Case 2, ECCE with intracapsular IOL implantation was followed 4 years later by an Nd:YAG capsulotomy; 6 months later the IOL dislocated into the vitreous cavity within this intact capsular bag. Different mechanlsms were responsible for the dislocation; in Case 1, radial tearing of the large capsular defect with IOL loosening and dislocation into the vitreous cavity; in Case 2, zonulysis and IOL dislocation within the intact capsular bag. A neodymium:YAG capsulotomy may cause delayed IOL dislocation into the vitreous cavity.

Visual outcome after paediatric cataract surgery: is age a major factor?

AIMSTo determine functional results after unilateral and bilateral cataract surgery in children with different aphakic optical correction.METHODSIn this retrospective study, we evaluated visual acuity and binocular vision in 107 children...

Flare-cell meter measurement of inflammation after uneventful cataract surgery with intraocular lens implantation

Purpose: To determine whether intracapsular intraocular lens (IOL) implantation leads to less anterior chamber inflammation than sulcus implantation in eyes having uneventful extracapsular cataract extraction (ECCE).Setting: Division of Ophthalmology, University of Alicante, Spain.Methods: This study comprised 314 consecutive uneventful ECCEs with implantation of a rigid poly(methyl methacrylate) IOL performed by the same surgeon. Inflammation was assessed by evaluating aqueous flare and cells using a laser flare-cell meter. Flare and cells were measured in both eyes of all patients preoperatively and on postoperative days 1, 2, 3, 4, 5, 7, 10, and 15 and at the end of months 1, 2, and 3. In 131 eyes (41.7%), the haptics were in the bag and in 114 (36.3%), in the sulcus. In 69 eyes (22.0%), implantation was combined sulcus-bag.Results: Flare and cell counts were high on day 1 regardless of the haptic placement. The counts were highest in eyes with sulcus implantation (32.4 ± 3.6 [SD] flare; 31.8 ± 3.2 cells) and lowest in eyes with in-the-bag implantation (27.5 ± 4.7 flare; 22.3 ± 2.8 cells). One day postoperatively, the difference between groups in cell count was statistically significant but not in flare measurements. There were no significant between-group differences on day 2 and thereafter. Thirty days postoperatively, flare and cell counts were similar in all eyes.Conclusion: Inflammation after uneventful ECCE with IOL implantation resolved within about 3 months of surgery, with flare and cell counts similar to those preoperatively. There was a small but detectable difference in flare and cell counts on the first day after surgery based on haptic location.

Goniometry with the Laser Tomographic Scanner (LTS) in ECCE

OBJECTIVES: The Laser Tomographic Scanner (LTS) allows horizontal and frontal section images of the anterior segment to be obtained. Horizontal x/z-section images were used for precision measurement of the chamber angle. The clinical feasibility was studied, using extracapsular cataract extaction (ECCE) + intraocular lens (IOL) implant as a model. DESIGN AND PATIENTS: Reproducibility was assessed by serial measurements (coefficient of variation = 7.5%; mean standard deviation = 2 ° ). Fifty patients were examined before (CA1) and 5-10 days after ECCE (CA2) with intracapsular IOLs. Increase of CA depth (D) postoperatively was determined with regard to CA1 and patient age. RESULTS: The following results were obtained: (i) the smaller CA1 the bigger the increase in D, (ii) in cases with deep CA1, only a moderate increase in D was observed; (iii) CA1 and CA2 are directly proportional; (iv) the older the patient at the time of surgery, the bigger the chamber angle increase in D to be expected. CONCLUSION: In this study, the first clinical approach, LTS-goniometry proved to be clinically feasible—it is a safe, easy to perform, accurate and optically reproducible method.

Mechanics of capsulorhexis

Continuous (central, circular) curvilinear capsulorhexis (CCC), first introduced by Gimbel and Neuhann, has become increasingly popular, especially for endolenticular phacoemulsification with intracapsular intraocular lens implantation. The principles of simple mechanics are used to facilitate teaching the procedure and to reduce the incidence of complications. A safe and simple method of performing CCC based on these principles is described.