Long-term results of the foldable CeeOn Edge intraocular lens

Intermediate Visual Acuity without Spectacles following Bilateral ReSTOR® Implantation

Purpose

This survey determined uncorrected visual acuity (VA) at near, intermediate, and far distances in cataract patients implanted with ReSTOR®, and assessed patient satisfaction.

Methods

Consecutive cataract patients implanted bilaterally with ReSTOR® were followed up at least 4 months. The Early Treatment Diabetic Retinopathy Study scale was used to measure VA for near (40 cm), intermediate (50, 60, and 70 cm), and distance vision, with VAs expressed in logMAR and adjusted for distance using Bennett's (1993) formula. Satisfaction was self-rated on a visual analogue scale ranging from 0 (poor) to 10 (high).

Results

Twenty-four consecutive patients (mean age 67.6 years) were operated upon by a single surgeon and followed up for a mean of 336.5 days after second eye surgery. Average postoperative VAs for uncorrected distance were 0.06 logMAR and intermediate VAs were 0.21 logMAR at both 50 cm and 60 cm and 0.22 logMAR at 70 cm. These levels of uncorrected intermediate VA would allow patients to read Word® computer text in Times New Roman font 8 zoomed to 100%, at 70 cm from the monitor screen. The authors found that 23/24 patients (96%) no longer wore spectacles. The remaining patient required correction for astigmatism as this refraction error is not yet correctable by ReSTOR®. Average self-rated satisfaction was 8.54.

Conclusions

In an everyday surgical practice, none of the studied bilateral ReSTOR® cataract patients without astigmatism required spectacles when followed up 6 months or later. Intermediate VA was compatible with reading and led to high patient satisfaction.

Long-term Results of Combined LASIK and Monocular Small-Aperture Corneal Inlay Implantation

PURPOSE

To evaluate the long-term effectiveness and safety of combined LASIK and small-aperture intracorneal inlay implantation (KAMRA; AcuFocus, Irvine, CA) for the surgical compensation of presbyopia and refractive errors.

METHODS

Retrospective chart review of all ametropic, presbyopic patients who underwent combined LASIK and KAMRA inlay implantation at a single clinic. Demographic data and preoperative uncorrected and corrected monocular and binocular near and distance visual acuity (UNVA, UDVA, and CDVA) with manifest refractive spherical equivalent (MRSE) were collected and analyzed. All perioperative adverse events were recorded.

RESULTS

In total, 132 patients were available (median age: 56 years; interquartile range (IQR) ± 5; range: 44 to 68 years). Median preoperative MRSE was +1.37± 1.20 diopters (D). The majority (113; 85%) were hypermetropic. Preoperative median UNVA improved from N24 (J13) ±6 to N6 (J5) ±1 by day 1 postoperatively, remaining stable throughout follow-up. At last follow-up, 97% of patients achieved UNVA of N5 (J3) or better. Median UDVA (implanted eye) improved from 20/40 (0.50 ± 0.41 on the decimal chart) preoperatively to 20/25 (0.80 ± 0.13) at month 12. Binocular UDVA was 20/20 in 88%, with CDVA unchanged for 84% at 12 months. No patient lost more than one line of CDVA. MRSE was also stable, albeit +0.25 D off-target refraction (-0.75 D). Two inlays were explanted due to suboptimal adaptation/corneal haze.

CONCLUSIONS

The results of this follow-up study show that combined insertion of a small-aperture corneal inlay with LASIK in presbyopic patients improves near vision with a slight compromise in distance vision in the implanted eye. Overall, it appears to be a safe, effective procedure for the treatment of presbyopia. [J Refract Surg. 2016;32(6):379-384.].

Prevention of capsule opacification after accommodating lens refilling: pilot study of strategies evaluated in a monkey model

PURPOSE

To test 2 strategies to prevent capsule opacification after accommodating lens refilling in a rhesus monkey model.

SETTING

Animal laboratory and laboratory of European university medical centers.

DESIGN

Experimental study.

METHODS

Six rhesus monkeys had refilling of the lens capsular bag. In the first strategy, before it was filled with a silicone polymer, the capsular bag was treated with noncommercial sodium hyaluronate 1.0% containing cytotoxic substances. In the second strategy, the capsular bag was filled with clinically used sodium hyaluronate 1.0% (Healon) after treatment with actinomycin-D. Slitlamp inspection was performed during a follow-up of 40 to 50 weeks. After enucleation, magnetic resonance images were obtained and confocal fluorescence imaging was performed.

RESULTS

Using the first strategy, capsule opacification developed in all eyes. Using the second strategy, 1 monkey did not develop capsule opacification after a 9-month follow-up. In a second monkey, the lens capsule remained clear for 3 months, after which the hyaluronate refill material was exchanged with a silicone polymer and capsule opacification developed. Combining these results with those in a previous study, the difference in opacification between silicone and sodium hyaluronate as refilling materials was statistically significant (P<.01).

CONCLUSIONS

That no capsular bag fibrosis occurred in the presence of hyaluronate suggests that the properties of hyaluronate are the reason that remaining lens epithelial cells do not develop into fibrotic cells. The choice of a suitable lens-refilling material prevents the development of capsule opacification.

FINANCIAL DISCLOSURE

Mr. Terwee was an employee of Abbott Medical Optics B.V. during the study period. No other author has a financial or proprietary interest in any material or method mentioned.

Corneal hysteresis, corneal resistance factor, and intraocular pressure measurements in eyes implanted with a small aperture corneal inlay

PURPOSE

To compare the postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) of eyes implanted with a small aperture corneal inlay versus fellow eyes.

METHODS

Medical records of patients who underwent small aperture corneal inlay (KAMRA; AcuFocus, Inc., Irvine, CA) implantation were retrospectively reviewed. There were two groups: the implanted and non-implanted. Main outcome measures were CH, CRF, Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc), and Goldmann applanation tonometry measurements performed preoperatively and at postoperative week 1 and months 1, 3, and 6.

RESULTS

The study included 68 eyes of 34 patients. CH was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (12.2 ± 3.1 vs 10.9 ± 1.7 mm Hg; P = .007) and month 1 (12.3 ± 2.5 vs 10.9 ± 1.8 mm Hg; P = .001). CRF was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (11.9 ± 2.9 vs 10.7 ± 1.6 mm Hg; P = .003) and month 1 (12.5 ± 2.5 vs 10.4 ± 1.8 mm Hg; P < .001). IOPcc was higher in the implanted group when compared with the non-implanted group at only the first postoperative month (17.1 ± 3.5 vs 14.3 ± 2.9 mm Hg; P < .001). There were no statistically significant differences in Goldmann applanation tonometry or IOPg measurements between the two groups (P > .05). At the 3-month postoperative visit, all parameters had returned to baseline and there was no change at the 6-month visit.

CONCLUSIONS

Implantation of the KAMRA corneal inlay does not induce a permanent change in CH or CRF. A transient increase in both was seen in the early postoperative period.

Comparison of outcomes with multifocal intraocular lenses: a meta-analysis

Purpose

To compare the clinical outcome of different multifocal intraocular lenses (IOLs) based on information reported in the international literature.

Methods

All comparative clinical trials that involved implanting at least one multifocal IOL in patients with cataract or presbyopia were extracted from the literature. Clinical outcomes included uncorrected near visual acuity, uncorrected distance visual acuity, visual acuity, spectacle independence, and halos. Random effects meta-analyses were conducted to compare outcomes for the different IOL types.

Results

Twenty papers were identified describing 11 monofocal IOLs and 35 multifocal IOLs (19 diffractive, including 12 ReSTOR^®, 14 refractive, and two accommodative) patient cohorts. Multifocal and monofocal uncorrected distance visual acuity was 0.165 (0.090–0.240) and 0.093 (0.088–0.098), respectively. Compared with monofocal IOLs, multifocal IOLs produced better uncorrected near visual acuity (0.470 [0.322–0.618] versus 0.141 [0.131–0.152]; P < 0.0001), resulting in higher spectacle independence (incidence rate ratio [IRR] 3.62 [2.90–4.52]; P < 0.0001). Compared with refractive multifocal IOLs, diffractive multifocal IOLs produced a similar uncorrected distance visual acuity (0.105 [0.098–0.111] versus 0.085 [0.029–0.140]; P ≤ 0.78, not significant) and better uncorrected near visual acuity (0.217 [0.118–0.317] versus 0.082 [0.067–0.098]; P < 0.0001) resulting in higher spectacle independence (IRR 1.75 [1.24–2.48]; P < 0.001). Compared with other multifocal IOLs, ReSTOR produced a better uncorrected distance visual acuity (0.067 [0.059–0.076] versus 0.093 [0.088–0.098]; P < 0.0001) and better uncorrected near visual acuity (0.064 [0.046–0.082] versus 0.141 [0.131–0.152]; P < 0.006), resulting in higher spectacle independence (IRR 2.06 [1.26–1.36]; P < 0.004). Halo incidence rates with different types of multifocal implants did not differ significantly.

Conclusion

Multifocal IOLs provide better uncorrected near visual acuity than monofocal IOLs, leading to less need for spectacles. Multifocal IOL design might play a role in postsurgical outcome, because better results were obtained with diffractive lenses. ReSTOR showed better uncorrected near visual acuity, uncorrected distance visual acuity, and higher spectacle independence rates compared with other multifocal IOLs.

Refractive surgical correction of presbyopia with the AcuFocus small aperture corneal inlay: two-year follow-up

PURPOSE

To evaluate the safety and efficacy of the AcuFocus Corneal Inlay 7000 (ACI 7000) implanted in emmetropic presbyopic patients for the improvement of near and intermediate vision over 2-year follow-up.

METHODS

This prospective, non-randomized, non-comparative study included 32 naturally emmetropic presbyopic patients. The intracorneal inlay was implanted in the non-dominant eye over the pupil by creating a superior-hinged flap with the IntraLase 60-kHz femtosecond laser (Abbott Medical Optics). Inlay centration was over the line of sight. Minimum postoperative follow-up was 24 months.

RESULTS

After mean follow-up of 24.2±0.8 months (range: 24 to 26 months), 96.9% of patients read J3 or better in the implanted eye. Mean binocular uncorrected near visual acuity improved from J6 preoperatively to J1 after 24 months. Mean binocular uncorrected intermediate visual acuity (UIVA) was 20/20 at 1 month and remained 20/20 throughout 24-month follow-up, with 71.9% of eyes reaching UIVA of 20/20 or better. At 24 months, mean uncorrected distance visual acuity was 20/20 in the implanted eye and 20/16 binocularly. No inlay was explanted during the study. Two decentered inlays were recentered after 6 months because of in-sufficient increase in near and intermediate visual acuity. Both patients' near and intermediate visual acuity improved significantly after recentration.

CONCLUSIONS

The ACI 7000 seems to provide a safe and effective treatment for presbyopia over follow-up of 2 years.

Modelling lifetime cost consequences of toric compared with standard IOLs in cataract surgery of astigmatic patients in four European countries

OBJECTIVE

To compare the lifetime costs of freeing astigmatic patients from spectacles after bilateral cataract surgery implanting toric intraocular lenses (IOLs: i.e., Acrysof Toric) versus monofocal IOLs, in France, Italy, Germany and Spain.

METHODS

A Markov model followed patient cohorts from cataract surgery until death. Prevalence rates of patients not needing spectacles and the types of spectacles prescribed for those requiring them were obtained from clinical trials and national surveys. The economic perspective was societal. Mortality rates were incorporated into the model. Discount rates were applied. A sensitivity analysis was performed on non-discounted costs.

RESULTS

Fewer patients with toric IOLs needed spectacles for distance vision than patients with monofocal IOLs. With monofocal IOLs more than 66% of patients needed complex spectacles compared to less than 25% implanted with toric IOLs. In France and Italy, toric IOLs reduced overall costs relative to otherwise high spectacle costs after cataract surgery. Savings were 897.0 euros (France), 822.5 euros (Germany), 895.8 euros (Italy) and 391.6 euros (Spain), without discounting. On applying a 3% discount rate the costs became 691.7 euros, 646.4 euros, 693.9 euros and 308.2 euros, respectively.

CONCLUSIONS

Bilateral toric IOL implants in astigmatic patients decreased spectacle dependence for distance vision and the need for complex spectacles. The economic consequences for patients depended on the national spectacle costs usually incurred after cataract surgery.

Intracorneal inlay for the surgical correction of presbyopia

PURPOSE

To evaluate the clinical safety and efficacy of the ACI-7000 intracorneal inlay in increasing the depth of field in emmetropic presbyopic patients.

SETTING

Beyoglu Eye Research and Education Hospital, Istanbul, Turkey.

METHODS

This prospective unmasked study comprised 39 presbyopic patients; 12 were naturally emmetropic and 27 had emmetropia resulting from previous hyperopic laser in situ keratomileusis. The intracorneal inlay was placed over the pupil in the patient's nondominant eye after flap lift or creation of a conventional flap using a microkeratome. The inlay was centered on the visual axis. Postoperative follow-up was 1 year.

RESULTS

Of the 39 inlays implanted, 3 were explanted during the study. At 1 year, the mean uncorrected near visual acuity improved from J6 (preoperatively) to J1+. All eyes with an inlay had an uncorrected near acuity of J3 or better and 85.3%, of J1 or better. Binocularly, the mean uncorrected near acuity remained J1 or better throughout the study. The mean uncorrected distance visual acuity in eyes with an inlay did not change significantly from preoperatively and remained 20/20 throughout the study period. All 3 eyes with inlay explantation returned to within +/-1.00 diopter of the preoperative refractive state for near and distance vision, with no loss of best corrected distance visual acuity.

CONCLUSION

The ACI-7000 intracorneal inlay showed the potential to provide safe, effective, and reversible treatment of presbyopia.

A European survey of patient satisfaction with spectacles after cataract surgery and the associated costs in four European countries (france, Germany, Spain, and Italy)

With multifocal intraocular lenses, the majority of the patients do not wear glasses after cataract surgery which is a potential source of savings.

PURPOSE

To collect data in four European countries on the associated costs for society of wearing spectacles after cataract surgery and the patient willingness to pay to be free of spectacles.

METHODS

Cross-sectional survey of centers that recruited patients who wore refractive spectacles after cataract surgery. Costs were expressed in 2006 Euros Results: 408 patients were recruited by 22 centers. Patients with a mean age of 68.5 years underwent cataract surgery about 3 years prior to recruitment. In all countries, prescribed lenses were mainly mono-focal and the mean cost of spectacles was EUR366.3. Half the patient population with private health insurance was reimbursed for spectacles at a level of 50%, except Spanish patients who were reimbursed at only 5.3%. However, a large part of the cost was directly paid by the patients. Out of a total mean cost of EUR354.9, patients paid EUR285.2 and health insurances only EUR69.7. More than half the patients were willing to pay at least 0.5EUR/day to be free of spectacles.

CONCLUSION

Large differences were found among the 4 countries. Almost half of all subjects had private health insurance. The total cost of refraction includes a variety of resources not limited to spectacles. A large part of the cost was borne by patients and there is a high patient willingness to pay to be free of spectacles in this population.

Modelling lifetime cost consequences of ReSTOR in cataract surgery in four European countries

BACKGROUND

To compare the lifetime costs of liberating patients from spectacles after cataract surgery by implanting the multifocal intraocular lens (IOL) 'ReSTOR' versus monofocal IOLs in France, Italy, Germany and Spain.

METHODS

A Markov model was created to follow patient cohorts from cataract surgery until death. Prevalence rates of patients not needing spectacles after cataract surgery were obtained from clinical trials. Resource utilisation included implant surgery, IOLs, spectacles, visits to ophthalmologists and eye centres, transport, and time lost by patients. Economic perspectives were those of Society and Sickness Funds (SFs).

RESULTS

The mean number of spectacles purchased after ReSTOR was 1.34-1.61 and after monofocal IOLs 6.05-7.27. From the societal perspective, total cost estimates discounted by 3% were between 3,551 euros and 4,052 euros with ReSTOR compared to 3,989 euros and 5,548 euros with monofocal IOLs. Undiscounted savings related to ReSTOR ranged from 815 euros to 2,164 euros. From the SFs' perspective total cost estimates discounted by 3% were between 2,150 euros and 2,524 euros with ReSTOR compared to 2,324 euros and 2,610 euros with monofocal IOLs. Savings related to ReSTOR, once costs discounted, ranged from 61 euros to 219 euros. Discount and spectacle freedom prevalence rates were the most sensitive parameters.

CONCLUSION

The bulk of the savings related to ReSTOR were realized outside the SF. From both a societal and SF perspective, savings, after a 3% discounting, achieved by liberating patients from spectacles counterbalanced the initially higher cost of ReSTOR. ReSTOR is a cost saving alternative to spectacles for patients requiring cataract surgery.

Genauigkeit der Linsenstärkenberechnung und Zentrierung einer asphärischen Intraokularlinse

BACKGROUND

Aspherical intraocular lenses (IOLs) are presumed to optimize the optical characteristics of IOLs. In order to profit from these characteristics, exact calculation of the IOL power and good centration of the lens are essential.

METHODS

In all, 43 eyes of 43 patients with an average age of 70.9+/-8.3 years underwent implantation of a Tecnis IOL (AMO, Ettlingen) after uneventful cataract surgery with topical anesthesia. IOL power calculation was performed using the Holladay, Haigis, and SRK II formulas. Spherical equivalent refraction and centration and position of the implanted IOLs were measured 6 months postoperatively. Centration of the IOL was analyzed using digital slit lamp photographs and an image analysis program.

RESULTS

Best corrected visual acuity (BCVA) increased from 0.47+/-0.25 (LogMAR) preoperatively to 0.1+/-0.11 6 months postoperatively (spherical equivalent +0.3+/-0.6 D). The intraindividual difference between target refraction and achieved postoperative refraction was 0.64+/-0.11 D for the Holladay formula, -0.21+/-0.11 D for the Haigis formula, and 0.97+/-0.15 D for the SRK II formula. The mean decentration of the IOL from the center of the corneal limbus was 0.4+/-0.1 mm.

CONCLUSIONS

For the aspherical Tecnis IOL very good postoperative functional results are reported, which are supported by an accurate calculation of the IOL power and a good centration of the IOL inside the capsular bag. In this study the Haigis formula showed the lowest difference between target refraction and achieved postoperative refraction.

Effect of surface coating an acrylic intraocular lens with poly(2-methacryloyloxyethyl phosphorylcholine) polymer on lens epithelial cell line behavior

PURPOSE

To evaluate the effect of surface coating of an acrylic intraocular lens (IOL) with poly(2-methacryloyloxyethyl phosphorylcholine) (MPC) on the behavior of the lens epithelial cell (LEC) line, alpha-TN4.

SETTING

Department of Ophthalmology, Nihon University School of Medicine, Tokyo, Japan.

METHODS

A hydrophobic soft acrylic IOL (AF-1, Hoya) was coated with MPC polymer. A noncoated IOL served as control. An IOL from each group was placed on the membrane of collagen I or IV of the cell culture dish. The alpha-TN4 cells were seeded in the insert. Cell behaviors (ie, cell proliferation and spreading) on IOLs and membranes were observed. Cell migration beneath the IOL optic portion was assayed using a computer software program (POCOman system) for posterior capsule opacification (PCO). Type I or IV collagen is the major matrix component of PCO or native lens capsule.

RESULTS

Cell proliferation was more marked on the noncoated IOL than on the coated IOL. Type IV collagen accelerated proliferation more than type I collagen. Cell migration to the area beneath the IOL optic was more prominent in the group with the type I collagen membrane and noncoated IOL than in other groups.

CONCLUSION

Coating an acrylic IOL surface with MPC polymer suppressed adhesion and proliferation of LECs, suggesting it improves IOL biocompatibility.

[Influence of intraocular lens material and design on the development of posterior capsule opacification]

Based on the literature of 1999-2005, we attempted to clarify the influence of material and design of an intraocular lens (IOL) on the development of posterior capsule opacification (PCO) and identify the future problems to be solved. The sharp edge design of an IOL has significantly reduced PCO in recent years. Histopathological studies showed that a sharp capsular bend was formed at the sharp posterior optic edge, and the migration of lens epithelial cells was obviously inhibited at the site. Experimental and clinical studies suggest that the sharper the edge is, the sharper the capsular bend, and the greater the preventive effect, regardless of IOL material. The sharp capsule bend appears to represent a physical hindrance, which may induce contact inhibition of cell movement. How material participates in the preventive effect should be clarified in a future study. Thus, at the moment, the formation of capsular bend at the posterior optic edge appears to be the decisive criterion to evaluate the influence of IOL material and design on the development of PCO. Optimization of design and material of an IOL, which facilitates capsular bend formation as sharply and quickly as possible, may reduce PCO to a clinically negligible level.

Three-year follow-up of posterior capsule opacification with two different silicone intraocular lenses

PURPOSE

To compare posterior capsule opacification (PCO) after cataract surgery with implantation of two silicone intraocular lenses (IOLs) with different designs.

METHODS

We carried out a prospective, clinical study of 116 patients randomized to standardized phacoemulsification with implantation of CeeOn Edge (n = 57) or SI40NB (n = 59) IOLs. The follow-up period was 3 years. To evaluate PCO morphologically, digital images were obtained and analysed using evaluation of posterior capsule opacification computer software (epco). The neodymium:YAG (Nd:YAG) capsulotomy rate was recorded.

RESULTS

At 2 and 3 years, the eyes with SI40NB IOLs had significantly more PCO than those with the CeeOn Edge IOLs (p = 0.00014 and p = 0.002). Nine Nd:YAG capsulotomies were performed in the SI40NB group and none in the CeeOn Edge group. This difference was statistically significant (p = 0.003). In some patients a regression of PCO was noticed and confirmed using epco. Statistically less PCO was noted when the capsulorhexis rim was placed so that it covered all 360 degrees of the optic of the IOL.

CONCLUSIONS

A clinically and statistically significant difference in PCO development between CeeOn Edge and SI40NB IOLs at 2 and 3 years postoperatively was found. These findings support earlier studies indicating that a sharp edge of the optic is a more important factor in IOL design than IOL material in the prevention of PCO.

Neodymium:YAG laser posterior capsulotomy after implantation of AcrySof intraocular lenses

PURPOSE

To report the incidence of neodymium:YAG (Nd:YAG) laser posterior capsulotomy after phacoemulsification and implantation of AcrySof (Alcon) intraocular lenses (IOLs).

SETTING

Private practice, Wolfe Clinic, Marshalltown, Iowa, USA.

METHODS

A retrospective diagnosis and procedure code review of 12419 consecutive cases having phacoemulsification and AcrySof IOL implantation from January 1995 through December 2002 was performed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies.

RESULTS

An Nd:YAG laser posterior capsulotomy was performed in 763 (6.1%) of the 12419 cases. The incidence of posterior capsulotomy was approximately 1% at 1 year, increasing in linear fashion by approximately 1% to 2% per year.

CONCLUSIONS

The Nd:YAG laser posterior capsulotomy rate after implantation of AcrySof IOLs was relatively low; the cumulative rate was approximately 1% to 2% new cases per year over a 7-year period, with a plateau suggested at year 6.

Use of Nd:YAG laser capsulotomy

Surgery for cataract removal has become successively refined such that posterior capsular opacification is the most common problem presenting after modern cataract extraction. Various techniques and treatments exist to manage patients with posterior capsular opacification using Nd:YAG capsulotomy. There are many possible variations in initial assessment, pre-laser treatments, laser techniques, and follow-up routines. The literature on the use of Nd:YAG laser for capsulotomy was reviewed and interpreted. This article presents the currently available knowledge in a format that allows the practitioner to tailor an evidence-based protocol for treating patients with symptomatic posterior capsule opacification.

Posterior capsule opacification after phacoemulsification: silicone CeeOn Edge versus acrylate AcrySof intraocular lens

PURPOSE

To compare the rates and morphologic features of posterior capsule opacification (PCO) after small-incision phacoemulsification and in-the-bag implantation of 2 foldable intraocular lenses (IOLs) over an 18-month follow-up.

SETTING

Departments of Ophthalmology, Hospital of Conegliano, Conegliano, and Maggiore Hospital of Bologna, Bologna, Italy.

METHODS

In an open clinical study, 78 cataract patients were randomly selected to have implantation of a silicone CeeOn Edge (Pharmacia) or acrylate AcrySof (Alcon) IOL after phacoemulsification cataract surgery. All the patients were operated on using a standard technique and in-the-bag IOL implantation. One eye in each patient was studied. Morphologic evaluation of PCO was performed using Evaluation of Posterior Capsule Opacification software.

RESULTS

At 18 months in the CeeOn Edge group, 36 eyes (90%) had a clear posterior capsule and 4 (10%) had PCO that did not affect visual acuity. In the AcrySof group, 26 eyes (68%) had a clear posterior capsule, 11 (29%) had PCO that did not affect visual acuity, and 1 (3%) had PCO with a decrease of 2 or more lines of visual acuity that required a neodymium:YAG laser capsulotomy. No eye developed Elschnig pearls or stretched folds in the bag. The postoperative best corrected visual acuity ranged from 0.8 to 1.0 in 96% in the CeeOn Edge group and in 92% in the AcrySof group. No IOL haze or discoloration was observed in the CeeOn Edge group. Mild IOL decentration and tilting occurred in 4 AcrySof eyes; however, no glistenings were found any AcrySof IOL.

CONCLUSIONS

Both the CeeOn Edge and AcrySof groups had a low incidence of PCO after an 18-month follow-up. The CeeOn Edge group had significantly less PCO than the AcrySof group. These results confirm that IOLs with square truncated edges create a barrier effect at the optic edge, reducing the overall incidence of PCO.

Inhibition of lens epithelial cell migration at the intraocular lens optic edge: role of capsule bending and contact pressure

PURPOSE

To evaluate the inhibitory effect of a sharp intraocular lens (IOL) optic edge, a sharp capsule bend, and contact pressure between the optic edge and posterior capsule on lens epithelial cell (LEC) migration.

SETTING

Department of Ophthalmology, Kyorin University, Tokyo, Japan.

METHODS

This in vitro laboratory study evaluated a tumble-polished convex-plano IOL (CP group), an AcrySof IOL (Alcon) with a sharp edge (AS group), a new IOL with a round ridge (RR group), and a new IOL with a sharp ridge (SR group). The 2 new IOLs have high ridges and high angled loops that create firm contact between the ridge and posterior capsule. After sham cataract surgery, an IOL and a capsular tension ring (CTR) were implanted in the capsular bag of rabbit eyes. The extracted capsular bags containing the CTR and IOL were cultured. The inhibitory effect of each IOL on cell migration was analyzed. Furthermore, LEC migration on the posterior capsule was compared in culture between capsules having a sharp right angle and those with gradually curving bends.

RESULTS

The inhibitory effect on cell migration was statistically greatest in the SR group followed by the RR, AS, and CP groups. A sharp capsule bend did not inhibit cell migration.

CONCLUSIONS

The results suggest that inhibition of cell migration at the optic edge is regulated by the degree of contact pressure between the optic edge and posterior capsule. A sharp capsule bend might indicate strong contact but does not in itself inhibit cell migration.

Effect of the optic size of a single-piece acrylic intraocular lens on posterior capsule opacification

PURPOSE

To investigate the effect of the optic size of an intraocular lens (IOL) with sharp optic edges on posterior capsule opacification (PCO).

SETTING

Nishi Eye Hospital, Osaka, Japan.

METHODS

In 5 rabbits, a single-piece 5.5 mm optic AcrySof IOL (Alcon Laboratories) was implanted in 1 eye and a specially fabricated single-piece 7.0 mm optic AcrySof IOL was implanted in the contralateral eye. Histopathological examinations were performed 3 weeks after surgery.

RESULTS

On posterior views, less PCO was noted with the 5.5 mm optic in all rabbits except 1. Histopathological sections demonstrated adhesion of the anterior and posterior capsules between the haptic and optic and the formation of a sharp capsular bend at the posterior optic edge in 3 eyes with the 5.5 mm optic but in no eye with the 7.0 mm optic. Abundant PCO was noted when a sharp capsular bend had not formed.

CONCLUSIONS

Capsular adhesion is a prerequisite of capsular-bend formation. The sharp optic edge alone does not provide a substantial barrier when a capsular bend is not formed. Bulky haptics such as those of the single-piece AcrySof and large optics may hamper capsular adhesion and bend formation.

Posterior capsule opacification and Nd:YAG capsulotomy rates after implantation of silicone, hydrogel and soft acrylic intraocular lenses: a two-year follow-up study

PURPOSE

To compare the posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) laser posterior capsulotomy rates associated with three different posterior chamber foldable intraocular lenses (IOL).

METHODS

We retrospectively evaluated the rates of PCO and Nd:YAG laser capsulotomy in 1150 eyes two years after standard phacoemulsification with a no-stitch 3.5mm clear corneal incision (CCI) and in-the-bag implantation of one of three types of IOL: 190 eyes received a one-piece round-edged hydrogel IOL (Hydroview H60M, Bausch & Lomb); 475 eyes a three-piece round-edged silicone IOL (AMO PhacoFlex SI-40NB, Allergan); 485 eyes a three-piece square-edged soft acrylic lens (AcrySof MA60MA, Alcon).

RESULTS

The PCO and Nd:YAG laser capsulotomy rates were respectively 43.15% and 20.5% in the Hydroview H60M group, 27.57% and 9.68% in the AMO PhacoFlex SI-40NB group, 10.5% and 2.47% in the AcrySof MA60MA group.

CONCLUSIONS

PCO and Nd:YAG laser capsulotomy rates were significantly higher in the Hydroview H60M group and significantly lower with the AcrySof MA60MA lenses, which combine a bioactive constitutive material with the square-edged optic design.

Performance of a truncated-edged silicone foldable intraocular lens in Indian eyes

PURPOSE

To study the role of truncated-edged silicone foldable intraocular lenses (IOLs) in preventing posterior capsule opacification (PCO) in Indian eyes.

SETTING

Cornea and Anterior Segment Service, L.V. Prasad Eye Institute, Hyderabad, India.

METHODS

This prospective study evaluated 39 Indian patients (39 eyes) with a mean age of 55.4 years who had uneventful implantation of the CeeOn Edge 911A IOL (Pharmacia). All IOLs were placed in the bag. Except in 4 patients, the capsulorhexis margin overlapped 360 degrees on the IOL optic periphery. The mean follow-up was 10.9 months (range 6.5 to 13.0 months); 32 patients were followed for 1 year.

RESULTS

Intraoperatively, posterior capsule fibrosis was noted in 7 patients. Diffuse haze was noted in the IOL optic in 1 patient. Clinically significant PCO did not occur in any case. One patient had clinically nonsignificant (grade 1) PCO at the 6- and 12-month follow-up visits. Although epithelial pearl accumulation (Soemmering's ring) was seen beyond the edge of the IOL in the 32 patients followed for 1 year, the epithelial pearls were central only in the patient with grade 1 PCO. Significant cell deposits were noted in 1 patient who had fibrinous uveitis at the 1-week postoperative visit; both resolved by 1 month. All eyes achieved a best corrected visual acuity of 20/30 or better.

CONCLUSIONS

The CeeOn Edge 911A IOL was well tolerated in Indian eyes, and the posterior capsule remained clear. Larger patient groups with a longer follow-up will provide more useful information.

Failure of a discontinuous bend to prevent lens epithelial cell migration in vitro

PURPOSE

To assess the effect of substrate geometry (discontinuous bend) on lens epithelial cell (LEC) growth in vitro.

SETTING

Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom.

METHODS

Culture wells with central depths of 0.4 mm, 1.0 mm, or 3.0 mm and a sharp square-edged profile (discontinuous bend) or a round-edged profile (continuous bend) were produced from a block of poly(methyl methacrylate). Freshly harvested bovine LECs were attached to the center of each well and cultured using standard techniques. Observations were made of whether LECs grew out of the wells and of the time required to do so.

RESULTS

Lens epithelial cells migrated out of all the wells. There was no significant difference in the rate at which they migrated out of round-edged and square-edged wells.

CONCLUSIONS

In vitro, a sharp discontinuous bend did not appear to induce contact inhibition of migrating LECs nor did it significantly hinder the rate at which LECs migrated. Therefore, a discontinuous bend in the lens capsule in isolation is unlikely to be responsible for the observed reduction in posterior capsule opacification associated with the use of square-edged IOLs.

Survey of intraocular lens material and design

Modern cataract surgery is constantly evolving and improving in terms of lens material and design. Researchers and physicians strive to obtain better refractive correction with smaller wound size and minimizing host cell response to limit the proliferation of lens epithelial cells leading to opacification of the lens capsule. Intraocular lens material varies in water content, refractive index, and tensile strength. Intraocular lens design has undergone revisions to prohibit lens epithelial cell migration and reflection of internal and external light. The evolution of intraocular lens and extracapsular cataract surgery has lead to faster postoperative recovery and better visual outcomes.