Complications of foldable intraocular lenses requiring explantation or secondary intervention--2007 survey update

Evaluation of Selected Biometric Parameters in Cataract Patients-A Comparison between Argos® and IOLMaster 700®: Two Swept-Source Optical Coherence Tomography-Based Biometers

Background and Objectives: To compare the biometry of eyes obtained with two swept-source optical coherence tomography-based biometers-Argos (A), using an individual refractive index, and IOLMaster 700 (IM), using an equivalent refractive index-for all structures. Materials and Methods: The biometry of 105 eyes of 105 patients before cataracts were analyzed in this study. Parameters such as axial length (AL), anterior chamber depth (ACD), and lens thickness (LT) were compared from both devices. According to the axial length measurements, patients were divided into three groups, as follows: group 1-short eyes (AL < 22.5 mm), group 2-average eyes (22.5 ≤ AL ≤ 26.0 mm), and group 3-long eyes (AL > 26.0 mm). Results: The correlation coefficiency among all compared parameters varies from R = 0.92 to R = 1.00, indicating excellent reliability of IM and A. A statistical significance in axial length was indicated in the group of short eyes (n = 26)-mean AL (A) 21.90 mm (±0.59 mm) vs. AL (IM) 21.8 mm ± (0.61 mm) (p < 0.001)-and in the group of long eyes (n = 5)-mean AL (A) 27.95 mm (±2.62 mm) vs. mean AL (IM) 28.10 mm (±2.64) (p < 0.05). In the group of average eyes (n = 74), outcomes were similar-mean AL (A) 23.56 mm (±0.70 mm) vs. mean AL (IM) 23,56 mm (±0.71 mm) (p > 0.05). The anterior chamber depth measurements were higher when obtained with Argos than with IOLMaster 700-mean ACD (A) 3.06 mm (±0.48 mm) vs. mean ACD (IM) 2.92 mm (±0.46) p < 0.001. There was no statistical significance in mean LT-mean LT (A) 4.75 mm (±0.46 mm) vs. mean LT (IM) 4.72 mm (±0.44 mm) (p = 0.054). The biometry of one eye with dense cataracts could be measured only with Argos, using the Enhanced Retinal Visualization mode. Conclusions: Axial length measurements from both devices were different in the groups of short and long eyes, but were comparable in the group of average eyes. The anterior chamber depth values obtained with Argos were higher than the measurements acquired with IOLMaster 700. These differences may be particularly important when selecting IOLs for patients with extreme AL values.

Indications and Outcomes of Intraocular Lens Explantation in a Tertiary Eyecare Center in Hungary between 2006 and 2020

Purpose

Our study aimed to evaluate the indications and outcomes of intraocular lens (IOL) explantation surgeries in a tertiary eyecare center in Hungary.

Materials and Methods

This retrospective study included all IOL explantation surgeries performed between 2006 and 2020 at the Department of Ophthalmology of Semmelweis University, Budapest, Hungary. There were no exclusion criteria for this study. For each patient, the demographics, clinical history, preoperative status, indications for IOL explantation, and operative and postoperative details were reviewed. Primary outcomes included explantation indications and the type of secondary implanted IOL.

Results

A total of 161 eyes from 153 patients were included (96 males; 62.7%); age at the time of the IOL explantation was 65.0 ± 17.4 years. The mean time between primary cataract surgery and IOL explantation was 8.5 ± 7.7 years. In total, 139 (86.3%) PCIOLs and 22 (13.7%) ACIOLs were explanted. The main indications for IOL explantation were dislocation (n = 133; 95.7%) and refractive cause (n = 2; 1.4%) in the PCIOL group. Among ACIOL explantations, the main reasons were pseudophakic bullous keratopathy (n = 14; 63.6%), dislocation (n = 4; 18.2%), and refractive cause (n = 2; 9.1%). In the PCIOL group, 115 (82.7%) primary IOLs were implanted in the capsular bag, 16 (11.5%) were sulcus fixated, and 8 (5.8%) were scleral fixated. The most frequent ocular comorbidities were previous vitrectomy (n = 50, 31.1%), previous ocular trauma (n = 45, 28.0%), glaucoma (n = 16, 9.9%), pseudoexfoliation syndrome (n = 15, 9.3%), and high axial myopia (n = 14, 8.7%). The most commonly used secondary IOL implant was the prepupillary iris-claw IOL (n = 115, 73.7%), followed by the retropupillary iris-claw IOL (n = 32, 20.5%). Uncorrected visual acuity (UCVA) was significantly better following IOL exchange in the entire sample (1.57 ± 0.61 (range: 2.40-0.05) vs. 0.77 ± 0.56 (range: 2.40-0.00); p < 0.001). Best-corrected visual acuity (BCVA) was maintained or improved in 80.7% of cases after IOL explantation.

Conclusions

The most common indication for IOL explantation at a tertiary eyecare center in Hungary is IOL dislocation, followed by pseudophakic bullous keratopathy. Prepupillary and retropupillary iris-claw IOL are the most frequently used secondary implants and their use resulted in a significant UCVA improvement following IOL exchange.

Managing dissatisfaction after multifocal intraocular lens implantation through lens exchange using monofocal or alternative multifocal IOLs

PURPOSE

To manage patient dissatisfaction following multifocal intraocular lens (MF-IOL) implantation by IOL exchange with either a monofocal or an alternative MF-IOL, and to compare outcomes in these two groups.

METHODS

MF-IOL exchange was performed in 32 patients (64 eyes) with neuroadaptation failure. The MF-to-MF group involved patients who had a MF-IOL exchanged with another MF-IOL of a different optical profile and the MF-to-MO group involved patients who had a MF-IOL exchanged to a monofocal IOL. Visual outcomes and complications were analysed. The Quality of Vision (QoV) questionnaire, Visual Function Index (VF-14) and its Rasch-revised version (VF-8R) were also used to assess outcomes.

RESULTS

There were no significant differences (p > 0.05) in the QoV scores between the two groups, both preoperatively and postoperatively. Preoperatively, there were no significant differences in VF-14 scores between both groups (p > 0.05). Postoperatively, there were statistically significant differences in VF-14 (total score, intermediate vision and near vision) in favour of the MF-to-MF group (p < 0.05). The postoperative VF-8R score in the MF-to-MF group was significantly better than the MF-to-MO group (p ≤ 0.001). Uncorrected and corrected near as well as corrected distance visual acuities were significantly better (p < 0.05) in the MF-to-MF group compared to the MF-to-MO group at 3 months.

CONCLUSION

Patient dissatisfaction and neuroadaptation failure following MF-IOL implantation can be managed by an IOL exchange with an alternative optical design of MF-IOL or a monofocal IOL. Although, in the current study, the MF-to-MF group showed some better postoperative results, both options are feasible solutions.

Direct Intraocular Lens Extraction Using a Newly Developed Lens-Grabbing Forceps

Background: Due to lower age thresholds for cataract surgery and increased longevity, cases with intraocular lens (IOL) dislocation requiring removal have increased. Traditional methods, such as cutting or folding the IOL within the eye, pose a high risk of complications, including corneal endothelial and iris damage. Methods: We developed a new minimally invasive technique for direct IOL removal using specially designed lens-grabbing forceps. These forceps can grasp and remove the IOL through a small incision in a single motion, significantly reducing intraocular manipulations compared to conventional methods. Results: In our test cases, IOL removal through a 2.2 mm corneal incision was completed in approximately 95 s, with minimal incision enlargement (about 0.16 mm) and a slight decrease in corneal endothelial cells. Conclusions: Our findings suggest that this technique is minimally invasive and safe for IOL removal, offering a promising alternative to existing methods.

Complications of foldable intraocular lenses requiring explantation or secondary intervention: 2022 survey with update of long-term trends

PURPOSE

To assess the complications that resulted in the explantation or secondary intervention with foldable intraocular lenses (IOLs).

SETTING

University setting, Salt Lake City, Utah.

DESIGN

Survey study.

METHODS

For the 25th consecutive year, surgeons were surveyed regarding complications associated with foldable IOLs requiring explantation or secondary intervention over the 2022 calendar year. These forms were made available online using the ASCRS and ESCRS websites and a fax-on-demand service. Surgeons completed 1 survey for each foldable IOL requiring explantation or secondary intervention. Further analysis determined complication trends related to specific IOL styles, materials, and types over the past 16 years (2007 to 2022).

RESULTS

103 completed surveys were returned in 2022 contributing to a total of 1627 tabulated surveys since 2007. In the 2022 survey, dislocation/decentration continued to be the most common complication overall. Glare/optical aberrations was a common complication associated with multifocal IOLs continuing a 16-year trend. In addition, hydrophilic acrylic IOLs as well as some silicone lenses in eyes with asteroid hyalosis demonstrated calcification as the most common complication necessitating explantation.

CONCLUSIONS

Dislocation/decentration remains the leading cause of explantation in most IOL types. Glare/optical aberrations continue to be an associated complication of multifocal IOLs suggesting this ongoing issue has yet to be resolved with this type of IOL. In addition, calcification of hydrophilic acrylic lenses and silicone lenses is a rare event but continues to occur.

Reversible Multifocality Achieved Through Polypseudophakia

Simultaneous implantation of a monofocal or monofocal toric intraocular lens (IOL) into the capsular bag and a multifocal IOL into the ciliary sulcus, referred to as duet procedure, allows us to create multifocality that is more easily reversible than the implantation of a capsular bag-fixated multifocal IOL. The optical quality and results after the duet procedure are equivalent to those of a capsular bag-fixated multifocal IOL. Patients who cannot tolerate the side effects of multifocal optics or who develop an ocular condition leading to loss of function such as age-related macular degeneration (AMD) or glaucoma in the course of their lives may benefit from the reversibility of the procedure.

Influence of decentration and tilt of Tecnis ZCB00 on visual acuity and higher order aberrations

BACKGROUND/OBJECTIVES

To determine the influence of decentration and tilt of a pseudophakic aspheric intraocular lens (IOL) on visual acuity (VA) and higher-order aberrations (HOAs), and to analyze the agreement between pupil center/axis and iridocorneal angles center/axis when assessing IOL decentration and tilt.

SUBJECTS/METHODS

A prospective interventional case series study including thirty-three patients undergoing Tecnis ZCB00 (Abbott Medical Optics) implantation. IOL decentration and tilt with respect to two reference systems (pupil and iridocorneal angles centers/axes), in cartesian (X,Y) and polar (radius/tilt, polar angle/azimuth) coordinates, were assessed with optical coherence tomography. VA and internal and ocular HOAs were evaluated. Multiple linear regression models and intraclass correlation coefficient (ICC) were computed.

RESULTS

IOL decentration only showed a significant effect on internal HOAs for [Formula: see text] (R2 = 0.20, P = 0.04). IOL decentration with respect to the pupil center showed a significant effect on ocular [Formula: see text] (R2 = 0.18, P = 0.05), [Formula: see text] (R2 = 0.36, P = 0.001) and [Formula: see text] (R2 = 0.24, P = 0.02); and with respect to the center of iridocorneal angles, on ocular [Formula: see text] (R2 = 0.21, P = 0.03), [Formula: see text] (R2 = 0.32, P = 0.003), primary coma (R2 = 0.41, P < 0.001), and coma-like (R2 = 0.40, P = 0.001). Poor agreement between both reference systems was found for IOL decentration measurements (ICC ≤ 0.41), except for the polar angle coordinate (ICC = 0.83). Tilt measurements showed good agreement (ICC ≥ 0.75).

CONCLUSIONS

Tecnis ZCB00 decentration and tilt values after uneventful implantation appear not to have influence on VA, and their effect on HOAs are not high enough to clinically affect quality of vision. Pupil and iridocorneal angles used as reference systems may be interchangeable for IOL tilt measurements, but not for decentration.

Indications and outcomes of intraocular Lens Exchange among pseudophakic eyes in a Tertiary Referral Center

PURPOSE

To determine the indications and surgical outcomes of intraocular lens (IOL) exchange in pseudophakic patients at Labbafinejad Tertiary Referral Center between 2014 and 2019.

METHODS

In this retrospective interventional case series, the medical records of 193 patients with a history of IOL exchange were reviewed. Preoperative data, including clinical characteristics, indications of the first and second IOL implantation, intra- and postoperative complications due to IOL exchange, and the pre-and postoperative refractive error and best-corrected visual acuity (BCVA) were considered the outcome measures in this study. All postoperative data were analyzed at least six months after follow-up.

RESULTS

The mean age of our participants was 59.13 ± 20.97 years old at the time of the IOL exchange, with a male percentage of 63.2%. The mean follow-up after the IOL exchange was 15.72 ± 16.28 months. The main indications of IOL exchange were IOL decentration (50.3%), corneal decompensation (30.6%), and residual refractive errors (8.3%). 57.10% of patients with the postoperative spherical equivalent at -2.00 diopter (D) to + 2.00D. The mean best-corrected visual acuity was 0.82 ± 0.76 LogMAR before the IOL exchange and was improved to 0.73 ± 0.79 LogMAR after the surgery. Corneal decompensation (6.2%), glaucoma (4.7%), retinal detachment (4.1%), cystoid macular edema (2.1%), and uveitis (1%) were found as the postoperative complications. There was only one case with suprachoroidal hemorrhage during IOL exchange.

CONCLUSIONS

IOL decentration followed by corneal decompensation was the most common indication of IOL exchange. After IOL exchange, the most complications during follow-up were corneal decompensation, glaucoma, retinal detachment, and cystoid macular edema.

Cataract surgery in Keratoconus revisited - An update on preoperative and intraoperative considerations and postoperative outcomes

PURPOSE

This review aims to evaluate and simplify the recent literature on preoperative surgical planning, intraoperative considerations, postoperative surprises, and their management in patients with keratoconus undergoing cataract surgery.

METHODS

A review of the literature was done to analyze all the pertinent articles on Keratoconus and cataract surgery.

RESULTS

The surgical planning of cataracts in eyes with keratoconus needs a multifaceted approach. Preoperatively, techniques such as cross-linking or the use of intra-corneal rings help stabilize the progression. Unreliable biometric measurements are a significant problem in keratoconus patients, especially in an advanced stage of the disease. It is better to consider actual K readings if the K value is less than 55D but for a K value, more than 55D using standard K values will prevent postoperative refractive surprises. For calculation of K values, an elevation-based device like pentacam gives better repeatability in mild to moderate cases whereas for advanced keratoconus none of the keratometers is reliable. Recently, the Kane keratoconus formula performed better in all stages of disease whereas previous studies showed good results with SRK/T formula is a mild and moderate disease. Monofocal intraocular lenses are a better choice in these patients. Toric lenses can be used in mild and stable keratoconus. Intraoperatively, the use of a customized RGP lens can overcome the challenge of image distortion and loss of visual perspective. Despite taking necessary measures, postoperative refractive surprise can occur and can be managed with IOL exchange or Secondary IOLs.

CONCLUSION

There is a spectrum of challenges in managing cataracts in keratoconus which makes thorough preoperative planning important for good surgical outcomes. Despite the measures, there might be post-operative surprises and the patients need to be informed regarding the same.

Patients’ dissatisfaction with multifocal intraocular lenses managed by exchange with other multifocal lenses of different optical profiles

Background

The aim of the study was to evaluate the outcomes of dissatisfied patients reporting poor visual quality following implantation of multifocal intraocular lenses (MF-IOLs), managed by IOL exchange with another multifocal optical profile.

Methods

This is a retrospective series of cases. MF-IOL exchange was done in 15 dissatisfied patients (30 eyes) with the perception of poor visual quality for far distance affected by neuroadaptation failure. Patients underwent a bilateral exchange of a MF-IOL with another MF-IOL of a different optical profile. Visual outcomes and complications were analyzed. Questionnaires including Quality of Vision (QoV), Visual Function Index-14 (VF-14) and its Rasch-revised version (VF-8R) and a satisfaction questionnaire were also used for outcome evaluation.

Results

The mean elapsed time from implantation to explantation-reimplantation was 11.8 months. The QoV scores improved significantly across all the three subscales. Visual function improved with a change in VF-14 score from 60.41 ± 24.81 to 90.16 ± 10.91 (P < 0.001). The VF-8R score improved as well. The uncorrected distance visual acuity improved from 0.24 to 0.12 logMAR after exchange (P < 0.001) and corrected distance visual acuity improved from 0.15 to 0.04 logMAR (P < 0.001). Safety and efficacy indexes reached 1.46 and 1.16, respectively. Concerning patients’ satisfaction following MF-IOL exchange, 80% of the patients reported they would have the MF-IOL reimplantation procedure again.

Conclusions

Patient dissatisfaction with neuroadaptation failure following MF-IOL implantation can be managed in 80% of our cases by MF-IOL exchange with a different MF-IOL optical profile.

Multifocal intraocular lens exchange to monofocal for the management of neuroadaptation failure

BACKGROUND

The aim of this study was to evaluate visual, refractive, quality of vision, visual function and satisfaction of multifocal intraocular lens (MF-IOL) exchange with a monofocal IOL (MNF-IOL) in dissatisfied patients following MF-IOL implantation.

METHODS

This was a retrospective case series. Bilateral IOL exchange (MF-IOL to MNF-IOL) was performed in 13 patients (26 eyes) with neuroadaptation failure. Questionnaires including the Quality of Vision (QoV), Visual Function Index (VF-14 and Rasch-revised VF-8R version), and a satisfaction questionnaire were used.

RESULTS

The mean time for IOL exchange was 15 months. The corrected distance visual acuity (CDVA) improved from 20/26 to 20/23 (P = 0.028). The uncorrected near visual acuity (UNVA) worsened after exchange from 20/47 to 20/62 (P = 0.024). QoV scores improved significantly across all three subscales after exchange. Visual function for far distance improved with a change in VF-14 score from 74.2 ± 24.8 to 90.9 ± 9.1 (P = 0.03). The VF-8R score showed worsening although not statistically significant. Near vision spectacle independence was totally or partially lost in all cases. Ten patients (77%) reported they would not repeat the lens exchange. Safety and efficacy indices changed from 1.23 to 0.85, respectively, at three months to 1.24 (P = 0.871) and 0.89 (P = 0.568), respectively, at one year.

CONCLUSION

IOL exchange (multifocal to monofocal) to solve neuroadaptation failure in this case series resulted in significant improvements in dysphotopsia and improved distance visual function. However, UNVA worsened and patient satisfaction after exchange remained suboptimal with 77% claiming they would not repeat the lens exchange, suggesting the value of near vision spectacle independence for these patients.

Monofocal intraocular lens with enhanced intermediate function as substitute for multifocal intraocular lens in positive dysphotopsia

Purpose

To present a case of a 62-year-old patient implanted with multifocal intraocular lenses (IOLs) who underwent a bilateral IOL exchange due to positive dysphotopsia. In an attempt to reduce the symptoms and compensate for the loss of multifocality, we implanted an aspheric monofocal IOL with enhanced intermediate function in one eye and a spherical monofocal IOL in the other eye.

Observations

The patient presented with complaints of halo and glare, measured with a simulator, following the implantation of segmented multifocal IOLs two years earlier. The uncorrected distance visual acuity (UDVA) was 20/20 in both eyes. Before presentation at our clinic, a laser capsulotomy had been performed on the right eye. We proceeded with a bilateral IOL exchange. Because of capsular insufficiency in the right eye, we implanted a spherical monofocal three-piece IOL in the ciliary sulcus with optic capture. In the left eye, we used a monofocal IOL with an enhanced intermediate function. Two weeks postoperatively, UDVA (monocularly) was 20/20 in OD and OS, the uncorrected intermediate visual acuity (UIVA) was 20/32, and the uncorrected near visual acuity (UNVA) was 20/50. Binocularly, UDVA was 20/20, UIVA was 20/25 and UNVA was 20/25. The patient reported a marked decrease in halos and glare.

Conclusions and importance

When planning IOL exchange surgery, in cases of intolerance to multifocal IOLs, the clinician should consider the dilemma of loss of multifocality. Recent developments in monofocal IOL technology present new options to improve visual function in cases of multifocal IOL explantation.

Intraoperative and Postoperative Intraocular Lens Opacifications: Analysis of 42545 Cases

Purpose

To assess the types and causes of intraocular lens (IOL) turbidity in a tertiary eye center. Setting. Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.

Design

Retrospective case series.

Methods

Patients who underwent uncomplicated phacoemulsification and IOL implantation for cataract between January 2015 and December 2019 were included. Medical records were reviewed of participants with intraoperative or postoperative IOL opacification for clinical data, artificial crystal materials, and causes of the opacification.

Results

A total of 42545 IOLs were implanted in the five years, comprising 25471 (66.0%) hydrophilic IOLs, 11881 (27.9%) hydrophobic IOLs, and 2601 (6.1%) hydrophilic-hydrophobic acrylic IOLs. Among the operated eyes, 14 eyes (13 patients) experienced IOL opacification, which was permanent for 10 IOLs, including 7 (0.6%) hydrophilic IOLs (860UV) and 3 (0.2%) hydrophilic-hydrophobic acrylic IOLs (L-312). The mean interval between surgery and diagnosis of permanent opacification was 34.4 ± 18.4 (SD) months (range, 12 to 59 months). Permanent IOL clouding led to a statistically significant reduction in best corrected visual acuity (mean, 0.64 ± 0.4 logMAR; P < 0.004). Acute IOL clouding occurred in four eyes during the implantation of a hydrophilic-hydrophobic acrylic IOL of L-312, 809M, or 839M and returned to transparency several hours later. All four procedures were performed in winter, with the mean outside temperature being −5.75°C.

Conclusions

The rate of IOL opacification was 0.03%. Both delayed postoperative and acute intraoperative opacifications occurred with various characteristics in IOLs made of different materials and designs. Clinicians should be aware of this risk for cataract surgery.

Cataract: Advances in surgery and whether surgery remains the only treatment in future

Background

Cataract is the world's leading eye disease that causes blindness. The prevalence of cataract aged 40 years and older is approximately 11.8%-18.8%. Currently, surgery is the only way to treat cataracts.

Main Text

From early intracapsular cataract extraction to extracapsular cataract extraction, to current phacoemulsification cataract surgery, the incision ranges from 12 to 3 ​mm, and sometimes to even 1.8 ​mm or less, and the revolution in cataract surgery is ongoing. Cataract surgery has transformed from vision recovery to refractive surgery, leading to the era of refractive cataract surgery, and premium intraocular lenses (IOLs) such as toric IOLs, multifocal IOLs, and extended depth-of-focus IOLs are being increasingly used to meet the individual needs of patients. With its advantages of providing better visual acuity and causing fewer complications, phacoemulsification is currently the mainstream cataract surgery technique worldwide. However, patient expectations for the safety and accuracy of the operation are continually increasing. Femtosecond laser-assisted cataract surgery (FLACS) has entered the public's field of vision. FLACS is a combination of new laser technology and artificial intelligence to replace fine manual clear corneal incision, capsulorhexis, and nuclear pre-fragmentation, providing new alternative technologies for patients and ophthalmologists. As FLACS matures, it is being increasingly applied in complex cases; however, some think it is not cost-effective. Although more than 26 million cataract surgeries are performed each year, there is still a gap in the prevalence of cataracts, especially in developing countries. Although cataract surgery is a nearly ideal procedure and complications are manageable, both patients and doctors dream of using drugs to cure cataracts. Is surgery really the only way to treat cataracts in the future? It has been verified by animal experiments that lanosterol therapy in rabbits and dogs could make cataract severity alleviated and lens transparency partially recovered. Although there is still much to learn about cataract reversal, this groundbreaking work provided a new strategy for the prevention and treatment of cataracts.

Conclusions

Although cataract surgery is nearly ideal, it is still insufficient, we expect the prospects for cataract drugs to be bright.

Visual outcomes after optic exchange of a modular intraocular lens

PURPOSE

To evaluate the effectiveness of the Harmoni Modular IOL (HMIOL).

SETTING

3 study sites.

DESIGN

Prospective, multicenter clinical study.

METHODS

HMIOL is a foldable, posterior chamber lens with separate base and exchangeable optic components. Eligible adults undergoing cataract surgery received HMIOL in the study eye (monovision target -1.50 diopters [D]) and standard monofocal IOL in contralateral eye (control). After 3 months, subjects could undergo optic exchange based on visual outcomes. End points included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refractive spherical equivalent (MRSE). Follow-up was 12 months or greater postoperatively.

RESULTS

114 subjects had successful HMIOL implantation in study eye and control IOL in contralateral eye. At 3 months, subjects could undergo optic exchange if unsatisfied with monovision; 65 eyes had optic exchange (exchange cohort), and 49 eyes had no exchange (no exchange cohort). In exchange cohort, the proportion of eyes with UDVA of 20/40 or greater and of 20/20 or greater increased 3 months after optic exchange vs preexchange levels by 23% (97% vs 74%) and 40% (49% vs 9%), respectively. In all cohorts, 95% of subjects or greater achieved UDVA of 20/40 or greater after 12 months or greater. Control and no exchange cohorts achieved CDVA of 20/40 or greater by 3 months; 97% of eyes or greater had CDVA of 20/40 or greater at 12 months after optic exchange. In exchange cohort, the proportion of eyes with MRSE within ±0.50 D and ±1.00 D of target changed by 57% and 36%, respectively, from preexchange (20% and 59%, respectively) to 12 months postexchange (77% and 95%, respectively), reaching levels similar to control subjects (72% and 97%, respectively).

CONCLUSIONS

HMIOL provided visual outcomes comparable with standard monofocal IOLs.

Multifocal IOL explantation in patients with opaque lentis after refractive lens exchange

PURPOSE

We describe the outcomes of intraocular lens (IOL) explantation in a cluster of opaque multifocal Lentis LS-313 following refractive lens exchange (RLE).

METHODS

Single-centre, single-surgeon, retrospective case series.

RESULTS

The study enrolled 10 eyes of 10 patients, 6 male and 4 female. All patients had uneventful RLE with multifocal IOL implantation. The mean patient age at the time of RLE was 53 years ± 2.52 (SD). Two eyes had YAG laser capsulotomy prior to explantation. The mean interval between the initial RLE and IOL explantation was 5.4 years ± 1.4 (SD). IOL exchange was performed in all eyes in one procedure. Five eyes had in the bag hydrophobic acrylic IOL (3 multifocal and 2 monofocal), three eyes had 3-piece hydrophobic acrylic IOL in the ciliary sulcus and two had an anterior chamber IOL. Intraoperatively one patient had weak zonules and two patients had zonular dehiscence and required anterior vitrectomy. The mean preoperative CDVA was 0.25 ± 0.15 (SD) logMAR and at the final follow-up, improved to 0.00 ± 0.07 (SD) logMAR (p < 0.01). Light microscopy with von Kossa stain confirmed IOL calcification. No postoperative complications were recorded.

CONCLUSIONS

IOL exchange appears to be a feasible and safe surgical option for multifocal IOL opacification. However, patients must be warned of additional intraoperative risks including zonular dialysis, vitreous loss, retinal detachment and need for potential scleral or iris fixated IOL or anterior chamber IOL (ACIOL) with its associated sequel of complications. Moreover, YAG laser capsulotomy should be considered carefully as it increases the chances of intraoperative complications and restricts the surgical options of secondary IOL insertion such as in-the-bag IOL exchange with MFIOL.

Microscopic Characteristics of Late Intraocular Lens Opacifications

CONTEXT.—

The increases in overall life expectancy and in lens surgeries performed on younger patients have resulted in a significant increase in the anticipated duration of artificial intraocular lenses (IOLs) in the eye. Thus, the physicochemical properties of the IOL become a critical issue, and several types of postoperative IOL opacifications have been reported.

OBJECTIVE.—

To describe the microscopic characteristics of opacified IOLs. Glistenings and subsurface nanoglistenings are fluid-related phenomena developing mainly in hydrophobic acrylic IOLs and are associated with aqueous influx into the IOL matrix. Calcification presents in hydrophilic acrylic or silicone IOLs as deposits of hydroxyapatite or other phases of calcium. Snowflake degeneration is less common, and it manifests in older polymethyl methacrylate IOLs.

DATA SOURCES.—

PubMed and ScienceDirect databases were searched for the following keywords: intraocular lens, IOL, cataract surgery, phacoemulsification, opacification, glistening, subsurface nanoglistenings, calcification, snowflake degeneration. English-language articles published up to October 15, 2019 were included in the study. The manuscript contains mainly a literature review; however, it was supplemented with original investigations from the David J. Apple International Laboratory for Ocular Pathology.

CONCLUSIONS.—

Glistenings and subsurface nanoglistenings should be evaluated in a hydrated state and at room temperature; they manifest as microvacuoles sized from 1.0 to greater than 25.0 μm and less than 200 nm, respectively. Calcification deposits are situated on or underneath the surface of the IOL and can be stained with a 1% alizarin red solution or with the von Kossa method. Snowflake degeneration manifests as "particles" or "crystals," causing whitish IOL discoloration. Scanning electron microscopy or energy dispersive X-ray spectroscopy may improve the diagnostic accuracy.

Explantation/exchange of the components of a new fluid-filled, modular, accommodating IOL

PURPOSE

To evaluate the ease of replacement and capsular stability of a new fluid-filled, modular, accommodating intraocular lens (IOL) system composed of a monofocal base lens with a fluid lens clipped inside of it.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Experimental study.

METHODS

Five New Zealand rabbits underwent bilateral phacoemulsification with implantation of the test lens (Juvene, LensGen, Inc.) in both eyes (4 rabbits), or a control IOL in 1 eye (AcrySof, Alcon Laboratories, Inc.) and the test IOL in the other (1 rabbit). At 2 weeks, the 4 rabbits with bilateral Juvene IOLs had the clipped-in fluid lens exchanged for a new fluid lens in 1 eye, and the base and fluid lenses exchanged for a control lens in the contralateral eye. Slitlamp examinations were performed weekly for 4 weeks. The globes were enucleated and evaluated with ultrasound biomicroscopy, grossly from the posterior Miyake-Apple view, and histopathologically.

RESULTS

Explantation/exchange of the fluid lens was considered straightforward by the surgeon. Explantation of the base lens (4) was also safely performed, albeit more demanding, without any signs of damage to the capsular bag under clinical, ultrasound biomicroscopy, and pathological examination in the exchanged eyes. Less capsular bag opacification was observed with the Juvene lens system.

CONCLUSIONS

Explantation/exchange of the fluid lens component, or both fluid and base lenses, of this new lens system can be safely accomplished if necessary, because of its modular design and the relative lack of postoperative capsular bag opacification associated with it.

Analysis of opacification patterns in intraocular lenses (IOL)

Objective

Intraocular lens (IOL) opacification may cause severe visual impairment. The pathogenesis remains unclear. The aim of this study was to analyse opacification patterns in different IOLs. Therefore, this multicentre, retrospective, observational study was conducted at Ludwig-Maximilians-University, Munich, Germany and University-Hospital Basel, Switzerland.

Methods and analysis

In this study, 75 opacified IOLs were identified and classified after extraction. Macroscopical photo documentation, light and electron microscopic analysis were done.

Results

68 acrylic-hydrophilic single-piece-IOLs, 1 acrylic-hydrophilic 3-piece-IOL, 6 acrylic-hydrophobic 3-piece-IOLs were extracted. The dataset comprised IOLs known for opacification and IOLs not having been reported yet. 67 IOLs showed a fine-granular and 8 IOLs a crust-like opacification pattern. According to literature, 62 of the fine-granular opacified IOLs were graded into type 1 (processing/packaging-induced primary opacification) and 13 into type 2 (secondary opacification of unknown aetiology). The anterior surface of the IOLs was affected in all 75 IOLs, the posterior surface only in 23 cases. Of all 67 fine-granular IOLs, 43 had a central defect and 21 had a zone without opacification (clear islet).

Conclusion

In our series, the morphology of IOL opacification did not follow the existing pathogenetic classification that strictly discriminates between primary and secondary causes. Fine-granular IOL opacification occurs with similar patterns in both type 1 and type 2 IOL opacification, while a crust-like pattern was only detected in type 2 IOL opacifications. Consequently, susceptibility of an IOL to opacification is caused by a multifactorial combination of material and processing properties as well as individual (pathological) conditions of the patient.

Evaluation of Safety Following Optic Exchange of a Modular Intraocular Lens

PURPOSE

To characterize safety of optic exchange using a modular lens.

SETTING

3 study sites (New Zealand, Philippines).

DESIGN

Prospective clinical study.

METHODS

Harmoni modular intraocular lens (HMIOL) with separate base and optic components was implanted in the study eye (monovision target -1.5 D). Contralateral eyes received standard monofocal lenses. Subjects could elect optic exchange 3 months after primary implantation. Adverse events (AEs) and endothelial cell loss (ECL) were assessed through 12-months follow-up.

RESULTS

114 subjects successfully received HMIOL and 114 received control lens in contralateral eye. At month 3, 65 HMIOL eyes had optic exchange due to unsatisfactory visual outcome from high monovision (Exchange cohort); 49 eyes received no exchange (No Exchange cohort). Exchange, No Exchange, and Control cohorts reported ocular AEs in 10 (15%), 6 (12%), and 14 (12%) eyes. No posterior capsular rupture occurred during optic exchange procedures. Short-term (12-month) posterior capsule opacification (PCO) evaluation showed all eyes had PCO grade ≤1 at month 12; no YAG capsulotomy was performed in the Exchange cohort. No Exchange and Exchange cohorts had similar ECL at 3 months versus preoperative baseline (-4.5%, n=48 and -4.0%, n=65). In the Exchange cohort, additional 2.7% ECL occurred 3 months after optic exchange compared with pre-exchange baseline; ECL was significantly below the 14% threshold (P<0.001) and was 5.8% at 12 months.

CONCLUSIONS

HMIOL safety outcomes were comparable with standard monofocal lenses; HMIOL may provide an effective method for correcting postoperative refractive errors.

[Functional rehabilitation of a patient with central opacification of the intraocular lens optic (clinical case)]

The authors present a clinical case of central opacification of the intraocular lens (IOL) optic associated with a significant uncorrectable visual acuity decrease. Due to high surgical risks of IOL exchange, corectopia was achieved through sectoral laser photomydriasis. Stable dilation of the lower nasal sector of the pupil enabled the optical zone to be shifted outside the opaque area of the IOL. As shown by the perimetry results, the visual field borders enlarged through sectoral laser photomydriasis were comparable with the topography of the asymmetrically dilated pupil.

Comparison of three different presbyopia-correcting intraocular lenses

Objective (aim): to test the refractive and visual outcomes and the quality of vision after the bilateral implantation of three different multifocal intraocular lenses (MIOLs) in patients with age-related cataract. Methods: In this retrospective, comparative study including 90 eyes of 45 cataract patients, bilateral implantation of either the hydrophilic trifocal Liberty® 677MY capsular bag IOL, the hydrophilic AT LISA® tri 839M lens, or the hydrophobic AcrySof® IQ PanOptix® IOL was performed during routine cataract surgery. Refractive outcomes, visual acuities (VA) for far, intermediate and near distances, as well as visual quality, dysphotopic events and spectacle use were evaluated six months postoperatively. Results: VA curves were similar for the three MIOLs, however the Liberty lens seemed to be superior for far and near, while AT LISA tri provided somewhat better VA in the intermediate range. Refractive correction was the most effective with the Liberty IOL (p=0.0131). Dysphotopic phenomena were usually perceived in low light conditions. Their frequency was lower with the AT LISA tri and Liberty lenses. Symptoms were significantly less disturbing for patients implanted with the Liberty lens, two-thirds of AT LISA tri and Liberty patients, while only 57% of PanOptix patients achieved spectacle independence. Conclusions: All examined MIOLs were found to be safe and efficient in presbyopia-correction of cataract patients, however different models had different advantages. The vision preferences of each patient should always be taken into consideration when choosing a MIOL, and the possible occurrence of dysphotopic events should be also clearly communicated in each case. Abbreviations: ACD = Anterior chamber depth, ANOVA = Analysis of variance, AXL = Axial length, CDVA = Corrected distance visual acuity, CYL = Cylinder; Cylindric refraction, D = Diopter, IOL = Intraocular lens, K1; K2 = Keratometry values, MIOL = Multifocal intraocular lens, n = Number of cases, n.a. = Not applicable, Postop = Postoperative, QoV = Quality of Vision, SD = Standard deviation, SEQ = Spherical equivalent, SPH = Sphere; Spherical refraction, UDVA = Uncorrected distance visual acuity, UIVA = Uncorrected intermediate visual acuity, UNVA = Uncorrected near visual acuity, VA = Visual acuity.

[Current Review: Multifocal Intraocular Lenses and Extended Depth of Focus Intraocular Lenses]

Presbyopia and cataract patients' wish to be increasingly independent of spectacles after surgery and this is one of the main drivers for the development of multifocal intraocular lenses (MIOL) and extended depth of focus (EDOF) intraocular lenses (IOL). As education, biometry, diagnostics, surgical techniques, and MIOL/EDOF IOL designs have improved over the past decade, an increasing number of cataract surgeons have become cataract refractive surgeons to help address this need. There is not one single MIOL/EDOF IOL, however, that suits all patients' needs. The wide variety of MIOL and EDOF IOL, their optics, and their impact on our patients' quality of vision have to be fully understood if we have to choose the appropriate IOL for each individual; MIOL/EDOF IOL surgery has to be customized. This review article looks at the different optical aspects and clinical consequences of MIOL/EDOF IOL, in order to help surgeons find an appropriate solution for each of their individual patients.

Intraocular Lenses: Overview of Designs, Materials, and Pathophysiologic Features

This article provides an overview of intraocular lenses (IOLs) currently used in cataract surgery. Aspects presented include design features related to IOL construction and sites of fixation; optic, filter, and haptic materials; as well as pathophysiologic features of uveal biocompatibility, capsular biocompatibility, and postoperative IOL opacification. This overview also includes supplementary (add-on; piggyback) lenses implanted in eyes that are already pseudophakic and considerations on IOLs used in the pediatric population. Different IOLs are made available to surgeons each year, including lenses with increasingly complex design characteristics owing to advancements in manufacturing and surgical techniques.

An evaluation of glistening and stability of intraocular lens material manufactured by different methods

PURPOSE

To evaluate glistening and long-term stability of five commercially available intraocular lenses.

METHODS

This experimental study evaluated the SN60WF (Alcon), XY1 (Hoya), NS-60YG (NIDEK), ZCB00V (Johnson & Johnson Vision) and AN6KA (Kowa) intraocular lenses. To generate glistenings, intraocular lenses were immersed in physiological saline at 50°C for 2 h, then left in situ at 35°C and removed at regular intervals over 24 h. Stability of the intraocular lens material was assessed by immersing intraocular lenses into vials of purified water placed at 100°C for 115 days, which simulated 20-year ageing. Gas chromatography-mass spectrometry was used to detect leached compounds.

RESULTS

Almost no glistenings were observed for the AN6KA. Glistenings were observed in the remaining intraocular lenses after 3 h. The number of glistenings gradually disappeared by 6 h for all intraocular lenses except SN60WF (12 h). Only the NS-60YG and ZCB00V intraocular lenses had no changes in weight or dimensions. Gas chromatography-mass spectrometry detected phenethyl alcohol in XY1 and SN60WF, 2-phenoxyethanol in AN6K and no compounds in the remaining intraocular lenses. A peak shift due to the carbonyl group between 1600 and 1700 cm^-1 was detected for the SN60WF and AN6K intraocular lenses only.

CONCLUSION

SN60WF had the most numerous glistenings that resolved over a longer duration. The long-term stability test confirmed elution of the intraocular lens material-derived compounds and signs of degradation for the XY1, SN60WF and AN6K intraocular lenses. NS-60YG and ZCB00V showed no signs of deterioration due to ageing. Differing manufacturing methods likely play a role in the stability of intraocular lenses.

Biocompatibility of intraocular lens power adjustment using a femtosecond laser in a rabbit model

PURPOSE

To evaluate the biocompatibility (uveal and capsular) of intraocular lens (IOL) power adjustment by a femtosecond laser obtained through increased hydrophilicity of targeted areas within the optic, creating the ability to build a refractive-index shaping lens within an existing IOL.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Experimental study.

METHODS

Six rabbits had phacoemulsification with bilateral implantation of a commercially available hydrophobic acrylic IOL. The postoperative power adjustment was performed 2 weeks after implantation in 1 eye of each rabbit. The animals were followed clinically for an additional 2 weeks and then killed humanely. Their globes were enucleated and bisected coronally just anterior to the equator for gross examination from the Miyake-Apple view to assess capsular bag opacification. After IOL explantation for power measurements, the globes were sectioned and processed for standard histopathology.

RESULTS

Slitlamp examinations performed after the laser treatments showed the formation of small gas bubbles behind the lenses that disappeared within a few hours. No postoperative inflammation or toxicity was observed in the treated eyes, and postoperative outcomes and histopathological examination results were similar to those in untreated eyes. The power measurements showed that the change in power obtained was consistent and within ±0.1 diopter of the target.

CONCLUSIONS

Consistent and precise power changes can be induced in the optic of commercially available IOLs in vivo by using a femtosecond laser to create a refractive-index shaping lens. The laser treatment of the IOLs was biocompatible.

Functional magnetic resonance imaging to assess neuroadaptation to multifocal intraocular lenses

PURPOSE

To evaluate the use of functional magnetic resonance imaging (MRI) to assess neuroadaptation to multifocal intraocular lenses (IOLs).

SETTING

Faculty of Medicine, University of Coimbra, Coimbra, Portugal.

DESIGN

Prospective case study.

METHODS

Patients with bilateral diffractive IOL implantation after cataract surgery had functional MRI at postoperative intervals of 3 weeks and 6 months. A nonintervention control group was included as proof of concept. Functional stimuli consisted of sinusoidal gratings with threshold contrast and a light source to induce disability glare. Subjective quality of vision and reading performance were assessed and wavefront analyses were performed.

RESULTS

The study comprised 30 patients in the study group and 15 in the control group. Glare decreased the functional MRI signal measured for sinusoidal gratings initially (3 weeks) but not at 6 months (P = .04), which was confirmed by contrast detection under glare improvement (P = .002). Patients showed increased activity of cortical areas involved in visual attention, procedural learning, effortful cognitive control, and goal-oriented behavior in the early postoperative period, which normalized at 6 months. There were no differences in aberrations, Strehl ratio, or modulation transfer function despite significant decreases in questionnaire symptom scores and visual acuity and reading performance improvements. The control group remained unchanged.

CONCLUSIONS

Neuroadaptation to multifocal IOLs took place initially through recruitment of visual attentional and procedural learning networks. Thereafter, a form of long-term adaptation/functional plasticity occurred, leading to brain activity regularization toward a non-effort pattern. These findings, which reinforce the crucial role of higher-level brain regions in the perceptual construction of vision, were consistent with functional and questionnaire outcomes and were unrelated to optical properties.

Transection and explantation of intraocular lenses using femtosecond lasers

We present 2 cases in which a femtosecond laser was used in vitro to transect hydrophilic acrylic intraocular lenses (IOLs). At 8 μJ with 3 μm spot separation and 6 μm line separation, no charring occurred and there was no increase in total organic carbon. In vivo, the IOLs were successfully transected in the capsular bag (Case 1, opaque IOL) and the sulcus (Case 2, subluxated IOL post-pneumatic displacement of submacular hemorrhage) and explanted through a clear corneal incision (∼3.0 mm). At 3 months, in Case 1, the corrected distance visual acuity (CDVA) improved from 6/24 to 6/5, astigmatism improved by 0.23 diopters, and endothelial cell density (ECD) remained unchanged (1935 to 2210 cells/mm²); in Case 2, the CDVA was hand motion, astigmatism remained unchanged, and ECD decreased (1960 to 1600 cells/mm²), possibly as a result of complex surgery. Femtosecond IOL transection and explantation may be a clinically safe and feasible option for surgeons.

Surgical removal of dystrophic calcification on a silicone intraocular lens in association with asteroid hyalosis

We present a case of successful removal of late calcium deposition on the posterior surface of a silicone intraocular lens (IOL) optic in association with asteroid hyalosis using a surgical technique that included pars plana vitrectomy, a lighted pick, and a modified silicone-tipped cannula. The lighted pick provided the most efficient and complete removal of calcium deposits. Postoperatively, the dystrophic calcification was removed and the IOL optic was clear at 6 months follow-up. The patient's symptoms resolved and uncorrected distance visual acuity returned to 20/20. This method can be considered in patients with dystrophic calcification of a silicone IOL in association with asteroid hyalosis and might avoid the need for IOL exchange and its associated complications and uncertain refractive outcomes.

Intraocular lens explantation in Spain: indications and outcomes at a tertiary referral center from 2010 to 2018

PURPOSE

To evaluate the causes of IOL explantation, techniques for secondary IOL implantation, visual outcomes and complications.

METHODS

Setting: Department of Ophthalmology Complexo Hospitalario Universitario A Coruña, Spain.

DESIGN

Retrospective study. All explanted IOLs from January 2010 to June 2018 were included. Medical records were reviewed to determine the surgical indication for IOL explantation, type of IOL implanted, time between surgeries, visual outcomes and surgical complications.

RESULTS

One hundred forty-one IOLs were explanted (134 patients). Mean time from original surgery to IOL explantation was 7.89 ± 5.81 years. Causes of IOL explantation were IOL dislocation (81.56%)-in-the-bag IOL dislocation (71.63%), out-of-the-bag IOL dislocation (9.9%)-corneal decompensation (12.05%), refractive surprise (3.5%), uveitis-glaucoma-hyphema syndrome (1.4%), IOL opacification (1.4%). Procedures for secondary IOL implantation were retropupillar iris-claw IOL (63.8%), flanged scleral fixated IOL (9.2%), three-piece IOL in ciliary sulcus (8.5%), angle-supported anterior chamber IOL (7.1%), in-the-bag IOL (3.5%), scleral fixated IOL with sutures (0.7%). Ten cases (7.1%) were left aphakic. Mean preoperative and postoperative logMAR CDVA were 1.34 ± 0.87 and 0.63 ± 0.69, respectively (p = 0.000). Mean preoperative IOP and postoperative IOP were 16.78 ± 4.49 and 15.53 ± 3.476 mmHg, respectively (p = 0.005). Complications include cystoid macular edema (7.8%), glaucoma (7.1%), IOL luxation (2.1%), retinal detachment (1.4%), trophic ulcer and leucoma (1.4%), corneal decompensation (1.4%).

CONCLUSIONS

In-the-bag IOL dislocation was the most frequent indication for IOL explantation, followed by pseudophakic bullous keratopathy. Simultaneous IOL exchange for a retropupillar iris-claw IOL was the most frequent procedure for secondary IOL implantation. Mean CDVA improved significantly and IOP decreased significantly after IOL explantation. The most frequent postoperative complication was cystoid macular edema.

A new device for intraocular lenses explantation

Intraocular lenses (IOLs) used in cataract surgery sometimes have to be explanted because of eventual complications like incorrect power, dysphotopsia, opacification, or rupture during implantation. However, current explantation procedures present several shortcomings related to the need for incision enlargement and/or potential damage to ocular structures. We present a new device which increases safety while cutting the lens, allowing the explantation through the original incision, and applicable to any type of IOL.

Laser treatment of silicone intraocular lens opacification associated with asteroid hyalosis

An 86-year-old Asian man with asteroid hyalosis presented with decreased vision in the left eye. He underwent phacoemulsification and implantation of silicone intraocular lens (IOL) in the left eye 18 years ago, and also received neodymium:yttrium–aluminum–garnet (Nd:YAG) laser 3 years ago. At presentation, his corrected visual acuity (CVA) was 20/1000 in the left eye. Slit-lamp examination showed white-gray membranous deposits on the posterior IOL surface. The deposits were removed using Nd:YAG laser treatment. One week later, his CVA improved to 20/30, and opacity of the posterior IOL surface was removed. Six months later, his CVA was 20/30, and visual axis was clear. This case suggests that Nd:YAG laser treatment can be a viable option in some patients with posterior surface opacification of silicone IOL associated with asteroid hyalosis, especially in those who are a poor candidate for IOL exchange due to old age or compromised general condition.

Frequency of Intraocular Lens Dislocation and Pseudophacodonesis, 20 Years After Cataract Surgery - A Prospective Study

PURPOSE

To examine the incidence and trends of late intraocular lens (IOL) dislocation/decentration and the frequency of pseudophakodonesis.

DESIGN

Prospective, population-based cohort study.

METHODS

A total of 800 patients were examined before cataract surgery in 1997-1998. Twenty years later, 100 of 133 survivors (75%) participated in the follow-up. An eye examination was performed including assessment for pseudophakodonesis and dislocation of the IOL. The medical records of all included patients at baseline were studied. Main outcome measures were previous IOL exchange or repositioning surgery, significant IOL dislocation, degree of pseudophakodonesis, and visual acuity.

RESULTS

Twenty years after the original cataract surgery, 10 of the 800 patients at risk (1.2%) had needed dislocation surgery. Before cataract surgery, 39% of all patients had pseudoexfoliations (PXF). Mean time from cataract surgery to dislocation surgery was 12 years 6 months (range 3 years 9 months to 19 years 3 months). The cumulative incidence over 20 years was 6% in patients with PXF and 2% without PXF at surgery (P = .035). Mean age at cataract surgery in the 10 dislocated cases was 68.3 years (range 58-80). Twenty years after surgery, 5 of 98 (5%) patients had moderate/pronounced pseudophakodonesis.

CONCLUSIONS

In this population-based cohort, the 20-year cumulative incidence of IOL dislocation needing surgical attention was significantly higher in patients with PXF than without PXF before surgery. The individual patient seems to have a low risk of being affected by this complication, but dislocated IOLs may cause a relatively large public health care burden, because of the large number of people in society with previous cataract surgery.

Secondary intraocular lens implantation: a large retrospective analysis

PURPOSE

To investigate preoperative ocular risk factors and indications for secondary intraocular lens (IOL) implantation and compare postoperative complications, visual and refractive outcomes in a tertiary referral center.

METHODS

Patients older than 14 years that underwent secondary IOL implantation and had a minimum follow-up of 3 months were enrolled in this retrospective case series. Preoperative ocular risk factors, indications for surgery, postoperative complications, and visual and refractive outcomes including prediction error (PE) and absolute error (AE) were evaluated. IOLs were fixated in following positions: anterior chamber (AC), retropupillary iris-claw (IC), sulcus, and capsular bag or sclera.

RESULTS

One-hundred eighty-two eyes of 174 patients with mean follow-up of 17 ± 13.6 months were evaluated. Leading cause for surgery was IOL dislocation (75%), followed by secondary aphakia (19%) and IOL opacifications (6%). Previous vitrectomy was the major preoperative ocular risk factor (43%). Mean corrected distance visual acuity improved from preoperative 0.68 ± 0.55 to 0.42 ± 0.31LogMAR by the last follow-up (p = 0.001). PE and AE differed highly depending on the indication for surgery (p = 0.041 and p = 0.008, respectively) and the IOL fixation (p = 0.011 and p = 0.028, respectively), with IC-IOLs showing the lowest PE and AE. Postoperative AC-hemorrhage occurred mainly after IC-IOLs (p = 0.003), and postoperative hypotony was significantly higher in eyes with previous uveitis (p = 0.026).

CONCLUSIONS

Previous vitrectomy seems to be a major underreported risk factor in eyes that undergo secondary IOL implantation. Refractive outcomes depend on indication for surgery and fixation type, with retropupillary IC-IOLs providing the best refractive results, though not statistically significant compared to other IOL positions.

Intraocular lens correction of presbyopia

The continued development of intraocular lens (IOL) technology has led to a dramatic improvement in refractive outcomes. New and innovative ways of achieving the desired postoperative refractive goals continue to be developed. This article aims to review the currently available IOL modalities for correction of presbyopia at the time of cataract surgery, including reference to high-quality comparative studies, where available, and discussion of strengths as well as limitations of the currently available IOL technologies. It has been shown that multifocal compared to monofocal IOL was associated with higher rates of spectacle independence, but higher rates and severity of symptomatic glare as well as reduced contrast sensitivity. Within multifocal IOLs, diffractive compared to refractive IOLs tended to have better near vision and a lower rate of symptomatic glare. Extended depth-of-focus IOLs compared to diffractive multifocal IOL demonstrated equal or superior intermediate visual acuity, with less than or equal rates of glare. Accommodative IOLs represent a broad range of technologies that continue to develop, and new technologies offering opportunities for postoperative adjustment of refractive outcome are emerging.

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

PURPOSE

To identify indications for and visual outcomes of intraocular lens (IOL) exchange to understand recent changes in this surgery.

SETTING

Academic tertiary referral center.

DESIGN

Retrospective case series.

METHODS

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.

RESULTS

The study comprised medical records of 109 eyes. The mean time between the primary cataract surgery and IOL exchange was 1657 days. 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 1 month 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%).

CONCLUSIONS

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.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Late postoperative opacification of a hydrophilic-hydrophobic acrylic intraocular lens

PURPOSE

To report late postoperative opacification of a model of hydrophilic-hydrophobic acrylic intraocular lens (IOL) as well as the clinical consequences and laboratory characteristics.

SETTING

Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.

DESIGN

Retrospective case series.

METHODS

Medical records were reviewed of patients with Lentis LS-502-1 IOL opacification reporting visual loss who had IOL explantation between November 2013 and March 2015. Patients were identified in the emergency room or during regular follow-up visits. Explanted IOLs were analyzed at the Ophthalmic Explants Biobank, Vissum, Spain, or at the John A. Moran Eye Center, University of Utah, USA.

RESULTS

Twenty opacified IOLs were explanted from 19 patients. The mean interval between cataract surgery and diagnosis of opacification was 29.15 months ± 9.57 (SD) (range 6 to 45 months). Opacification led to a statistically significant reduction in corrected distance visual acuity (mean 0.86 ± 0.76 logMAR; P < .001) and occurred in 5.1% of the hydrophilic-hydrophobic acrylic IOLs implanted at the department. The most frequently associated medical conditions were arterial hypertension, diabetes, and glaucoma. All IOLs but 1 had a similar pattern of opacification, with yellowish diffuse opacification uniformly distributed and calcium deposits on the surface and/or subsurface of the optic and haptics and within the IOL material.

CONCLUSIONS

Opacification of the hydrophilic-hydrophobic acrylic IOL was found in a significant number of patients and had a significant effect on their vision. The opacification was attributed to primary calcification.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Serial intraocular lens opacifications of different designs from the same manufacturer: Clinical and light microscopic results of 71 explant cases

PURPOSE

To report clinical findings and light microscopic results of 71 opacified hydrophilic acrylic intraocular lenses (IOLs).

SETTING

Vivantes Klinikum Neukoelln, Ophthalmology Department, Berlin, Germany.

DESIGN

Retrospective case series.

METHODS

Sixty-three patients (71 eyes) were referred to the clinic because of vision-impairing IOL opacification between December 2012 and September 2016 after routine cataract surgery elsewhere. The explanted IOLs were analyzed with light microscopy at the John A. Moran Eye Center (University of Utah, Salt Lake City, Utah, USA). Medical records were reviewed for visual acuity, comorbidities, and complications. Clinical follow up was 6 months.

RESULTS

Seventy-one opacified 1-piece or 3-piece hydrophilic acrylic IOLs (Lentis) of different designs from 2009 to 2012 (LS-502-1, LS-402-1Y, LS 312-1Y, LS-313-1Y, L-402, L-312) were found. Morphological findings were surface, subsurface, or deep calcifications of the IOL material. Explantation was performed 4 years ± 1.2 (SD) after initial phacoemulsification. The mean patient age was 78.6 ± 8.2 years. Ocular and systemic comorbidities were found without statistical correlation: the most frequent were diabetes, uveitis, and glaucoma. The preoperative mean corrected distance visual acuity changed from 0.63 ± 0.47 logarithm of the minimum angle of resolution (logMAR) to 0.20 ± 0.28 logMAR postoperatively (P < .001).

CONCLUSIONS

Different designs of IOLs by the same manufacturer, implanted between 2009 and 2012, developed late calcification with significant visual loss after routine cataract surgery. No medical, surgical, or ophthalmologic trigger could be determined. A manufacture issue might be the reason for the opacification.

Long-term uveal and capsular biocompatibility of a novel modular intraocular lens system

BACKGROUND

We evaluated the long-term biocompatibility and safety of a new modular posterior chamber intraocular lens (IOL) system in rabbit eyes.

METHODS

Seven New Zealand rabbits underwent bilateral phacoemulsification with placement of the modular IOL in OD and a control IOL (SA60AT) in OS. Slit-lamp examinations were performed at postoperative weeks 1, 2, 3, 4, 6 and 8 and months 3 and 6. All rabbits were then sacrificed and eyes enucleated. The eyes were examined grossly from the Miyake-Apple view. Selected IOLs were explanted and underwent surface staining for implant cytology. All globes were then sectioned and processed for histopathological examination.

RESULTS

The modular IOL remained stable in all seven rabbits through the entire follow-up period. Biocompatibility was better than the control lens at six months postoperatively, on account of less extensive synechiae formation as assessed by slit-lamp examination. At the six-week examination, posterior capsule opacification (PCO) was significantly better in the test group (scored as 1.71 ± 0.8 versus 3.28 ± 0.48 in the control group, p = 0.0008). On gross examination with the Miyake-Apple view, Soemmering's ring formation was significantly better in the test group, (5.14 ± 1.57 versus 10.85 ± 1.95 in the control group, p = 0.002).

CONCLUSION

Previous studies showed that explantation/exchange of the modular system optic was safer and easier than with a standard IOL. The new modular IOL system has demonstrated better long-term biocompatibility compared to the control lens at six months postoperatively in the rabbit model.

Premium intraocular lenses: The past, present and future

Purpose

To present potential benefits as well as limitations of premium intraocular lens (IOL) use, and provide insight in future of premium cataract surgery.

Methods

Bibliographic research was performed in PubMed/Medline database, and the most recently updated papers were evaluated. Keywords used were: premium intraocular lens, multifocal intraocular lens, toric intraocular lens, toric multifocal intraocular lens, accommodative intraocular lens, and the respective brand names.

Results

Multifocal IOLs provide uncorrected distance visual acuity (UDVA) of 0.03 logMAR in 82.3%–95.7% of patients and overall spectacle independence in 81%–85% of patients. Toric IOLs provide UDVA of 0.3 logMAR in 70%–95% of patients, residual astigmatism of 1 D or less is noted in 67%–88% of patients, and spectacle independence is reported in 60%–85% of patients. Toric multifocal IOLs provide UDVA of 0.3 logMAR in 92%–97% of patients, and spectacle independence is reported in 79%–90% of patients. Accommodative IOLs represent intensively developing field in ophthalmology, and the results are still variable depending on the IOL model.

Conclusions

Premium IOL technology and advanced surgical techniques have significantly improved postoperative visual outcomes. Future developments will potentiate development of new premium IOL designs that will provide spectacle independence and excellent visual outcomes after cataract surgery.

Scanning electron microscopic characteristics of manually loaded and preloaded foldable acrylic intraocular lenses

PURPOSE:

To compare surface alterations between preloaded and manually loaded intraocular lens.

METHODS:

Scanning electron microscope was utilized to evaluate surface alteration and deposits in four different types of intraocular lenses: preloaded hydrophobic acrylic, preloaded hydrophilic acrylic, manually loaded hydrophobic acrylic, and manually loaded hydrophilic acrylic. Six lenses with different powers (+6 D, +22 D, and +29 D) were used from each category, to represent different thickness categories of the intraocular lenses.

RESULTS:

In total, 30 intraocular lenses have been evaluated in this study: 4 from the control group (2 hydrophobic and 2 hydrophilic lenses) and 12 from the preloaded intraocular lens and manually loaded groups (6 hydrophilic and 6 hydrophobic lenses with different powers). Surface deposits were found in eight hydrophobic intraocular lenses compared to a single intraocular lens with scattered deposits on the optical surface of a hydrophilic intraocular lens. In manually loaded intraocular lens group, five hydrophobic and one hydrophilic intraocular lenses showed identifiable marks on the optical surface. In the preloaded intraocular lens group, three hydrophobic intraocular lenses showed identifiable marks on the optical surface and three hydrophobic intraocular lenses showed surface wrinkling. All hydrophilic intraocular lenses revealed no identifiable marks.

CONCLUSION:

Surface alterations and deposits are a common finding in both preloaded and manually loaded intraocular lenses. Water content of acrylic intraocular lenses is an important factor predisposing to these changes, and hydrophobic intraocular lenses are more vulnerable than hydrophilic lenses. The impact on the final visual outcome needs further studies.

[Capsule contraction syndrome in pseudophakia]

This is a review of the literature on capsule contraction syndrome (CCS) in pseudophakic patients that involves severe fibrosis along the margin of the anterior capsule's opening and progressive contraction of the capsular bag. Possible causes of CCS and principles of its prevention and treatment have been analyzed.