Three-year clinical comparison of 3-piece AcrySof and SI-40 silicone intraocular lenses

Posterior Capsule Opacification after Cataract Surgery via Implantation with Hydrophobic Acrylic Lens Compared with Silicone Intraocular Lens: A Systematic Review and Meta-Analysis

Hydrophobic acrylic intraocular lens (IOL) is the most popular material in cataract surgery. Posterior capsule opacification (PCO) is a long-term complication of cataract surgery. It can impair vision and adversely affect the prognosis of IOL delamination. The objective of this study was to perform a systematic review and meta-analysis to provide an updated evaluation of long-term complications and visual function after implantation with hydrophobic acrylic and silicone intraocular lenses. PubMed, Embase, and Cochrane Library were searched from January 2000 until March 2021. Randomized controlled trials (RCTs) and retrospective studies were finally included. The main outcomes were PCO value and neodymium-doped yttrium aluminum garnet (Nd : YAG) capsulotomy rate. Subgroup analysis was performed to compare hydrophobic acrylic and silicone IOLs during the follow-up period. Sensitivity analysis was also performed. The meta-analysis included a total of 17 studies. When the follow-up period was considered, the results of the analysis revealed higher PCO value (Group 3: standardized mean difference (SMD), −0.59; 95% confidence interval (CI), −0.90 to −0.28) and Nd : YAG capsulotomy rate (Group 3: risk ratio (RR), 0.60; 95% CI, 0.40–0.89) for hydrophobic acrylic IOLs than silicone IOLs during a long-term (≥6 years) follow-up. In conclusion, both the PCO value and the Nd : YAG capsulotomy rates were higher in hydrophobic acrylic IOLs group than the silicone IOLs group at long-term use (more than 6 years) after implantation.

Open-capsule intraocular lens to prevent posterior capsule opacification

PURPOSE

To develop a single-piece open-capsule intraocular lens (IOL) that can be inserted through a small incision and that prevents posterior capsule opacification (PCO) by expanding the capsule and circulating aqueous humor into the capsular bag.

SETTING

Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan.

DESIGN

Experimental study.

METHOD

Using the same hydrophobic acrylic material as the NY-60 IOL, a prototype open-capsule IOL was constructed. The IOL has a single optic and 2 haptics, with a 2.8 mm high spacer and holes through which aqueous humor circulates into the capsular bag by separating the anterior capsule from the posterior capsule and expanding the capsule. The open-capsule IOL or NY-60 (as a control group) was inserted in rabbit eyes. Posterior capsule opacification development was evaluated by measuring the thickness of the cell layer at the center of the posterior capsule on histopathologic specimens and statistically comparing the thickness between the open-capsule IOL group and control group.

RESULTS

The open-capsule IOL could be inserted through a 3.2 mm corneal incision using a D cartridge. The mean thickness of the cell layer at the center of the posterior capsule was 4.78 μm ± 2.61 (SD) in the open-capsule IOL group and 101.14 ± 25.19 μm in the control group and was significantly smaller in the open-capsule IOL group.

CONCLUSION

The prototype single-piece IOL could be implanted through a small incision and prevented PCO by expanding the lens capsule and circulating aqueous humor into the capsular bag.

Physicochemical and surface properties of acrylic intraocular lenses and their clinical significance

To analyze and compare several commercially available acrylic intraocular lenses (IOLs) with particular regard to their clinical significance, we examined the physicochemical and surface properties of four currently available acrylic IOLs using static water contact angle, atomic force microscopy (AFM), Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. The hydrophobic acrylic IOLs, ZA9003, and MA60BM, had contact angles ranging from 77.9° ± 0.65° to 84.4° ± 0.09°. The contact angles in the hydrophilic acrylic (970C) and heparin-surface-modified (HSM) hydrophilic acrylic IOLs (BioVue) were 61.8° ± 0.45° and 69.7° ± 0.76°, respectively. The roughness of the IOL optic surface differed depending on the type of IOL (p < 0.001). The surface roughness of BioVue had the lowest value: 5.87 ± 1.26 nm. This suggests that the BioVue IOL may lead to reduced cellular adhesion compared to the unmodified IOLs. All IOLs including those composed of acrylic optic materials from different manufacturers showed distinct Raman spectra peaks. The glass transition temperatures (T_g) for the hydrophobic acrylic IOLs were between 12.5 and 13.8 °C. These results suggest that the intraoperative and postoperative behavior of an IOL can be predicted. This information is also expected to contribute greatly to the industrial production of reliable biocompatible IOLs.

The effect of single-piece hydrophobic acrylic intraocular lenses on the development of posterior capsule opacification

PURPOSE

To evaluate the long-term effect of a single-piece hydrophobic acrylic intraocular lens (IOL), AcrySof SN60AT (Alcon Laboratories, Fort Worth, Texas, USA), on the development of posterior capsule opacification (PCO) 5 years postoperatively.

DESIGN

Prospective, observational, consecutive, case series.

METHODS

setting: Iladevi Cataract and IOL Research Center, Ahmedabad, India.

STUDY POPULATION

Three hundred and ninety eyes with uncomplicated age-related cataract were included. Patients with diabetes mellitus, glaucoma, high myopia, pseudoexfoliation, traumatic cataract, subluxated cataract, previous ocular surgeries, and allergy to dilating drops were excluded. intervention procedures: Digital retroillumination photographic documentation was performed and analyzed for PCO using Evaluation of Posterior Capsule Opacification software. The scores and areas were calculated.

MAIN OUTCOME MEASURES

PCO development and the influence of the anterior capsule cover (total on and part on) on the IOL optic was studied within the capsulorrhexis margin and the central 3.0 mm optic area.

RESULTS

There was a significant increase in PCO up to 3 years. No significant change in PCO was observed between 3 and 5 years within the capsulorrhexis margin and central 3.0 mm optic area. In the total on group, within the capsulorrhexis margin, significantly lower scores and areas were observed when compared with part-on scores and areas.

CONCLUSION

The increase in PCO up to 3 years was significant. Stabilization in PCO was observed between 3 and 5 years with no difference at 5 years. There was a low incidence of PCO in eyes with total anterior capsule cover over the IOL optic.

Rate of posterior capsule opacification in eyes with the Akreos intraocular lens

PURPOSE

To determine the rate of posterior capsule opacification (PCO) in eyes with an Akreos Adapt or Akreos Fit intraocular lens (IOL) (Bausch & Lomb) over a minimum follow-up of 18 months.

SETTING

Department of Ophthalmology, Worthing and Southlands Hospital NHS Trust, Worthing, United Kingdom.

METHOD

This was a retrospective analysis of 102 patients who had uneventful phacoemulsification with implantation of an Akreos Adapt IOL or Akreos Fit IOL from September 2001 to May 2004. Patients from a single surgeon's operating list were recruited into the study. Exclusion criteria included posterior subcapsular cataract, history of uveitis, diabetic retinopathy, glaucoma, and age-related macular degeneration. The protocol included the determination of logMAR best corrected visual acuity (BCVA) and PCO scoring using the Evaluation of Posterior Capsular Opacification System (EPCO 2000) by digital photography of the posterior capsule. The number of patients having a neodymium:YAG (Nd:YAG) capsulotomy was also recorded.

RESULTS

The mean follow-up was 30 months +/- 10.3 (SD). The mean BCVA was 20/32 (0.2 logMAR). The mean EPCO score at the central 6.0 mm of the posterior capsule was 0.39 +/- 0.53 and at the central 3.0 mm, 0.18 +/- 0.40. The Nd:YAG capsulotomy rate was 8.8%.

CONCLUSIONS

All patients had stable visual acuity with low rates of PCO 2.5 years after surgery. The PCO rate with the Akreos IOL was similar to that with other acrylic IOLs reported in the literature.

Posterior capsule opacification

PURPOSE OF REVIEW

This paper assesses the factors that contribute to the formation of an effective capsular bend as a deterrent to posterior capsule opacification. Its goal is to assist the practicing ophthalmologist in separating current understanding of this process from various working models previously proposed.

RECENT FINDINGS

While a square-edge design appreciably improves resistance to posterior capsule opacification, significant factors remain under the control of the surgeon. These factors combine to form the physical and psychological barrier of a capsular bend. Innovative digital imaging has shown lens epithelial cell migration, allowing for a more rapid assessment of posterior capsule opacification resistance. A three-piece intraocular lens allows for full 360 degree capsular bend formation surrounding the optic edge; some single-piece designs may inhibit capsular bend formation. Decreasing, but not eliminating, the surviving lens epithelial cell population may diminish capsular bend strength, which may decrease resistance to posterior capsule opacification in the face of a regenerating cortex. All demographic features of clear/refractive lens exchange suggest higher rates of posterior capsule opacification than with standard cataract surgery.

SUMMARY

The quality of capsular bend formation will determine how resistant an intraocular lens will be to posterior capsule opacification as a consequence of regenerating cortex. As refractive lens exchange and new accommodating intraocular lens designs become more popular, the problems of regenerating cortex will increase in magnitude.

Quantitative Nachstarevaluierung von Acrylat- und Silikonintraokularlinsen mit scharfem Kantendesign

BACKGROUND

At the Department of Ophthalmology, Heidelberg, Germany, posterior capsule opacification (PCO) of a silicone and an acrylic intraocular lens (IOL) with a sharp optic edge design was evaluated.

PATIENTS AND METHODS

In a prospective study either the AMO ClariFlex silicone IOL or the Sensar AR40e hydrophobic acrylic IOL were implanted in 47 patients following uneventful phacoemulsification. Mean patient age was 76.2+/-7.8 (ClariFlex) and 73.4+/-12.9 years (AR40e), respectively. The mean follow-up time was 19.7+/-5.34 in the ClariFlex and 21.9+/-1.89 months in the AR40e group. PCO development was evaluated postoperatively using the EPCO 2000 analysis software (scale 0-4). Areas of interest were the total IOL optic, the central 3-mm zone as well as the capsulorhexis.

RESULTS

In both groups, all patients achieved a BCVA of 20/32 (AR40e) and 20/25 (ClariFlex), respectively. There was a very low incidence of PCO development with a mean EPCO score of 0.07+/-0.2 (ClariFlex and 0.15+/-0.2 (AR40e). Within the 3-mm zone and the capsulorhexis, there was a tendency for even lower EPCO scores in both groups. We calculated a statistically significant difference for the two lens materials for all investigated IOL areas (Wilcoxon's test, p<0.05).

CONCLUSION

Both IOLs with a sharp edge design showed good functional results, a stable position in the capsular bag as well as a low incidence of PCO development. However, the silicone IOL showed statistically significantly lower PCO scores.

Biological compatibility of polymethyl methacrylate, hydrophilic acrylic and hydrophobic acrylic intraocular lenses

PURPOSE

Extensive clinical investigations of the biocompatibility of different intraocular lenses (IOLs) have been made in an effort to optimize the outcome of modern cataract surgery. The aim of this study was to add animal eye experimental implantation data regarding cellular reaction on the anterior surface of IOLs.

METHODS

Thirteen adult albino rabbits had phacoemulsification/aspiration of the crystalline lens followed by implantation of a posterior chamber IOL in each eye. Three types of IOLs were studied: Hydroview (Bausch and Lomb; n = 7), Acrysof (Alcon, USA; n = 7), and polymethyl methacrylate (PMMA; HOYA, Japan; n = 7). The animals were killed by intravenous pentobarbital 1, 4, or 8 weeks later. The IOLs were explanted and stained with hematoxylin and eosin, and observed under a light microscope. The shape of mouse ascites-induced macrophages on the anterior surface of the three different IOL types (Hydroview, PMMA, and Acrysof) was studied after 24 h of oven culture.

RESULTS

Hydrophilic acrylic IOLs showed the highest affinity for lens epithelial cell (LEC) outgrowth, and the lowest and slowest maturation rate reaction of macrophages. PMMA IOLs showed the lowest affinity for LEC outgrowth, and the highest reaction of macrophages. Hydrophobic acrylic IOLs showed intermediate results both regarding LECs and macrophages.

CONCLUSIONS

Results suggest that IOL biomaterial properties are the key factor that influences the quantity of monocytes/macrophages as well as the process of their maturation/senescence. LEC outgrowth is influenced both by the biomaterial of IOLs and by the monocyte/macrophage reaction.

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.

The effect of lens edge design versus anterior capsule overlap on posterior capsule opacification

PURPOSE

To determine whether lens edge design or anterior capsule overlap on the intraocular lens (IOL) has greater effect on posterior capsule opacification (PCO).

DESIGN

Retrospective cohort clinical study.

METHODS

Retrospective.

SETTING

Academic clinical practice.

PATIENT POPULATION

The patient population consisted of 259 uncomplicated surgical patients (259 eyes) with no confounding comorbidity and at least 1 year of follow-up after surgical placement of a silicone or hydrophobic acrylic lens.

OBSERVATION PROCEDURES

Digital retroilluminated photographs were taken to ascertain PCO, anterior capsular opacification (ACO), previous neodymium:YAG capsulotomy and degree of anterior capsule overlap on the IOL optic.

MAIN OUTCOME MEASURES

PCO, ACO, YAG capsulotomy rate, and anterior capsule overlap on the IOL optic.

RESULTS

One hundred forty-eight digital images (74 silicone and 74 acrylic) were measurable for both anterior capsule overlap and PCO. Complete 360 degrees of anterior capsule overlap on the IOL was associated with decreased PCO (P = <.001). A significant negative correlation was found between the degree of anterior capsule overlap and PCO (P = <.001). Evaluation of PCO, and YAG capsulotomy rates were similar between acrylic and silicone lenses. Minimal anterior capsule overlap may also be associated with PCO prevention.

CONCLUSIONS

Implanting a lens with complete anterior capsule overlap on the IOL was found to significantly reduce PCO, which advantage appeared to be greater than PCO prevention by a truncated, sharp edge IOL design.

Effect of a silicone intraocular lens with a sharp posterior optic edge on posterior capsule opacification

PURPOSE

To compare the inhibiting effect on posterior capsule opacification (PCO) of a silicone intraocular lens (IOL) with a sharp posterior optic edge (ClariFlex OptiEdge, Advanced Medical Optics) and a silicone IOL with a round optic edge (PhacoFlex SI-40, Advanced Medical Optics).

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This prospective randomized patient- and examiner-masked study comprised 104 eyes of 52 patients with bilateral age-related cataract. All patients had cataract surgery in both eyes and received a sharp-edged IOL in 1 eye and a round-edged IOL in the other eye. Postoperative examinations were at 1 week, 1 and 6 months, and 1 year. Digital slitlamp and retroillumination images were taken of each eye. The amount of PCO was assessed subjectively at the slitlamp and objectively using Automated Quantification of After-Cataract (AQUA) automated-image analysis software.

RESULTS

The sharp-edged IOL group had significantly less regeneratory and fibrotic PCO 1 month, 6 months, and 1 year after surgery. The mean AQUA PCO score (scale 0 to 10) was 0.71 in the sharp-edged IOL group and 1.40 in the round-edged IOL group (P<.001). The sharp-edged IOL group had less peripheral fibrotic PCO. There was no significant difference between the 2 IOL groups in patient reports of edge glare.

CONCLUSION

The sharp-edged design of the ClariFlex OptiEdge silicone IOL led to significantly less PCO than the round-edged PhacoFlex SI-40 IOL 1 year postoperatively.

Posterior capsule opacification after implantation of CeeOn Edge 911A, PhacoFlex SI-40NB, and AcrySof MA60BM lenses

PURPOSE

To perform an intraindividual comparison of posterior capsule opacification (PCO) with 2 foldable intraocular lenses (IOLs) and a foldable acrylic IOL 1 year after in-the-bag implantation.

SETTINGS

Seven German ophthalmology centers.

METHODS

In an open prospective randomized multicenter study, each center intraindividually compared a high-refractive-index, sharp-edged optic silicone IOL (CeeOn Edge 911A, Pharmacia) with a high-refractive-index, round-edged optic silicone IOL (PhacoFlex SI-40NB, Allergan) or a sharp-edged optic acrylic IOL (AcrySof MA60BM, Alcon). Of 288 randomized patients, 247 had standard phacoemulsification with in-the-bag IOL implantation in both eyes by the same surgeon. One eye of each patient received a CeeOn Edge IOL and the fellow eye, an AcrySof or PhacoFlex IOL. A morphologic evaluation of PCO was performed using the Evaluation of Posterior Capsule Opacification (EPCO) system 1 to 2 weeks and 11 to 14 months after surgery. The digital pictures were evaluated by an independent investigator who was blind to the type of IOL. Intraindividual differences in EPCO scores were statistically evaluated by a 1-sided binomial test at an alpha-level of 5%.

RESULTS

One year after surgery, 127 patients with the AcrySof IOL and 102 patients with the PhacoFlex IOL in the control eye were reexamined. Functional results, safety, and handling were not significantly different between the 3 IOLs. All reexamined eyes had a very low PCO grade. The EPCO values revealed less PCO in eyes with the CeeOn Edge IOL than in eyes with the AcrySof or PhacoFlex IOL, but the difference was not statistically significant. A neodymium:YAG laser capsulotomy was performed in 1 eye with a CeeOn Edge IOL, 1 eye with an AcrySof IOL, and 2 eyes with a PhacoFlex IOL.

CONCLUSIONS

The EPCO PCO grade was low 1 year after implantation of CeeOn Edge 911A, PhacoFlex SI-40NB, and AcrySof MA60BM IOLs; there was no statistically significant difference between the IOLs. The impact of IOL material and edge design on PCO development might be relevant in a long-term follow-up of this study.

Anterior capsule relationship of the AcryS of intraocular lens optic and posterior capsule opacification

OBJECTIVE

To evaluate the relationship of the anterior capsule and the AcrySof MA30BA intraocular lens (IOL) and its impact on the development of central posterior capsule opacification (PCO).

DESIGN

Prospective, randomized, controlled trial.

PARTICIPANTS

Two hundred two patients with senile cataracts received an AcrySof IOL between July and December 1998 at Iladevi Cataract and IOL Research Center, Ahmedabad, India.

INTERVENTION

Patients were randomized prospectively to receive 1 of the 3 possibilities of anterior capsule and IOL optic relationship: group 1, total anterior capsule cover (360 degrees ) of the optic; group 2, no anterior capsule cover (360 degrees ) of the optic; group 3, partial anterior capsule cover (<360 degrees ) of the optic. After surgery, slit-lamp video photography was performed every 6 months for 3 years. Analyses of variance and chi-square tests were used to compare treatment groups.

MAIN OUTCOME MEASURES

Incidence of PCO in the 3 groups. The posterior capsule was divided into 3 zones: peripheral, central 3 mm, and midperipheral (the space between the peripheral and the central zones).

RESULTS

The average follow-up was 35.3 +/- 1.52 months in all the groups. At 3 years, the rate of central PCO was 6.4% in group 1, 7.1% in group 2, and 5.9% in group 3 (P = 0.9). Midperipheral PCO was present in 24.2% in group 1, 16% in group 2, and 20.6% in group 3 (P = 0.9). Peripheral PCO was seen in 100% of patients in all groups. The neodynium:yttrium-aluminum-garnet laser (Nd:YAG) posterior capsulotomy rate was 0% in all groups.

CONCLUSIONS

There was no significant difference in the incidence of development of central PCO among the 3 groups. No patient experienced central PCO that required Nd:YAG capsulotomy. When using the AcrySof IOL model MA30BA, the relationship of the anterior capsule and the IOL does not seem to be a factor that relates to the development of central PCO.

A clinical comparison of single-piece and three-piece truncated hydrophobic acrylic intraocular lenses

PURPOSE

To determine the clinical differences between three-piece (3P) and single-piece (SP) truncated hydrophobic acrylic intraocular lenses (IOL).

DESIGN

Retrospective cohort clinical study.

METHODS

The setting was an academic clinical practice. The patient population consisted of subjects without confounding comorbidity that could effect central vision with at least 1-year follow-up after uncomplicated surgical placement of 3P or SP IOLs in the capsular bag and at least 20/25 best-corrected postoperative vision documented. Observation procedures were as follows: logarithm of the minimal angle of resolution (LogMAR) visual acuity (uncorrected and best corrected), digital retroillumination photographs to ascertain posterior capsular opacification (PCO), anterior capsular opacification (ACO), IOL centration, and refractive stability by comparing this refraction with the early postoperative refraction. Patients completed a dysphotopsia questionnaire. Main outcome measures were as follows: LogMAR visual acuity (uncorrected and best corrected), PCO, ACO, IOL centration, refractive stability, and dysphotopsia outcomes comparing 3P and SP.

RESULTS

Seventy-five patients were enrolled (36 3P and 39 SP). Corrected and uncorrected visual acuity, refractive stability, and IOL centration were similar. Single piece truncated hydrophobic acrylic intraocular lenses had more PCO (P =.013), less ACO (P =.001), less central flash looking at a peripheral light (P =.044), and less unwanted images to the side of a light source (P =.025) .

CONCLUSIONS

Although similar in centration and refractive stability, SP has more PCO, less ACO, and less dysphotopsia than 3P.

Posterior capsule opacification: silicone plate-haptic versus AcrySof intraocular lenses

PURPOSE

To evaluate posterior capsule opacification (PCO) in fellow eyes, 1 receiving a silicone intraocular lens (IOL) and the other, an acrylate IOL.

SETTING

Department of Ophthalmology, Isala Clinics, Zwolle, The Netherlands.

METHODS

This retrospective study comprised 107 patients (214 eyes). In each patient, 1 eye was randomly selected to have implantation of an acrylate IOL (AcrySof MA30BA or MA60BM, Alcon) and the other eye, a plate-haptic silicone IOL (AA4203VF, Staar). Outcome measures were the total PCO index, percentage of neodymium:YAG (Nd:YAG) capsulotomies performed, and logMAR best corrected visual acuity (BCVA). The follow-up was 3 years.

RESULTS

The total PCO index was significantly lower in the AcrySof group than in the plate-haptic silicone group (P<.0001). There was no significant difference in logMAR BCVA between groups (P>.05). The percentage of Nd:YAG laser treatments was significantly lower in the AcrySof group (2.8%) than in the plate-haptic silicone group (23.1%) (P<.05).

CONCLUSIONS

There was significantly less PCO and a lower Nd:YAG laser capsulotomy rate after AcrySof IOL implantation than after plate-haptic silicone IOL implantation. These results did not seem to affect the logMAR BCVA as there were no significant differences between groups in this parameter.

Hydrophobic acrylic versus heparin surface-modified polymethylmethacrylate intraocular lens: a biocompatibility study

BACKGROUND

The implant of intraocular lenses (IOLs) following cataract surgery induces a foreign-body reaction to the IOL and a response on the part of the lens epithelial cells (LECs). The purpose of this study was to compare these aspects after the implantation of two different IOL materials.

METHODS

Thirty-six cataract patients were randomised to receive two different foldable lens: an acrylic hydrophobic IOL (Acrysof MA30BA) and a heparin surface-modified (HSM) polymethylmethacrylate IOL (Pharmacia & Upjohn 809C) after phacoemulsification. Slit-lamp biomicroscopy with specular technique was used to assess the inflammatory cell adhesion on the anterior IOL surface, anterior capsule opacification (ACO) and membrane growth from the rhexis edge at 7, 30, 90, 180 and 360 days after surgery.

RESULTS

The 809C group showed a higher percentage of patients with slight inflammatory cell adhesion on the anterior cell surface and a higher small cellular density during the whole follow-up period. The epithelioid cell response was greater in the 809C group than the Acrysof group but the difference between the two groups was not statistically significant. The ACO increased during the follow-up in both groups but was significantly higher in the 809C group.

CONCLUSION

Acrysof lenses are more biocompatible than HSM IOLs, showing a lower grade of inflammatory cell adhesion and ACO. The implantation of these lenses may be particularly indicated in patients with pathologies predisposing to blood-aqueous barrier damage.

Cataract treatment in the beginning of the 21st century

PURPOSE

To describe the principles upon which present day cataract treatment success resides.

DESIGN

Literature review and collective experience of the authors.

RESULTS

Surgical removal remains the standard treatment for cataract now and in the foreseeable future. Ultrasound cataract removal with a foldable "in-the-bag" intraocular lens with a truncated edge treated for dysphotopsia best correlates with core treatment principles, as we now understand them. Improving refractive results is an important trend. The worldwide burden of this problem is immense.

CONCLUSIONS

While results for treatment of cataracts are excellent today, improvements in safety and refraction precision are needed. Other approaches are desperately needed to stem the worldwide tide of cataract related ocular dysfunction.