Posterior capsule opacification with AcrySof and poly(methyl methacrylate) intraocular lenses. Comparative study with a 3-year follow-up

Posterior Capsule Opacification With Two Hydrophobic Acrylic Intraocular Lenses: 3-Year Results of a Randomized Trial

PURPOSE

To compare the incidence and intensity of posterior capsule opacification (PCO) and neodymium-yttrium-aluminum-garnet (Nd:YAG) capsulotomy rates between 2 similar open-loop single-piece hydrophobic acrylic intraocular lenses (IOLs) that differ in the proprietary material characteristics and design features, over a period of 3 years.

DESIGN

Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison.

METHODS

Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

PATIENT POPULATION

Eighty patients (160 eyes) had bilateral cataract surgery and received a Vivinex XY1 IOL in 1 eye and an AcrySof SN60WF IOL in the other eye.

OBSERVATION PROCEDURES

Follow-up examinations were performed 3 years after surgery. Digital retroillumination images were taken of each eye. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (AQUA).

MAIN OUTCOME MEASURE

PCO score (scale, 0-10).

RESULTS

The mean objective PCO score of the Vivinex XY1 IOLs was 0.9 ± 0.8 compared to the PCO score of 1.4 ± 1.1 for the AcrySof SN60WF IOLs (P < .001). Three years postoperatively, 11.4% of patients had an Nd:YAG capsulotomy in the Vivinex XY1 eye and 18.6% had a capsulotomy in the AcrySof SN60WF eye (P = .23).

CONCLUSION

The new hydrophobic acrylic Vivinex XY1 IOL showed significantly lower PCO rates and lower YAG rates compared to the AcrySof SN60WF IOL. The interaction of various factors such as hydrophobic material, smooth optic surface, and sharp posterior optic edge plays a key role in PCO development.

Late postoperative opacification of a hydrophobic acrylic intraocular lens AcryNovaTMPC 610Y

PURPOSE

To report late postoperative opacification of a hydrophobic acrylic intraocular lens (IOL) AcryNovaTMPC 610Y as well as the clinical consequences in patients 10 years after uncomplicated cataract surgery.

MATERIALS AND METHODS

Medical records were reviewed of 23 patients (26 eyes) with AcryNovaTMPC 610Y implantated between years 2005 and 2007. Next clinical examination was performed 10 years after surgery. We assessed best corrected distance visual acuity (BCDVA), contrast sensitivity (CSV-1000E) and relative opacity of IOL material, (OCULUS Pentacam HR). Results of BCDVA and Pentacam were analysed statistically. One explanted IOL was analysed using anterior segment OCT in vitro and spectroscopic method EDX (Energy-dispersive X-ray spectroscopy).

RESULTS

Opacification led to a statistically significant reduction in the best corrected distance visual acuity (BCDVA) = (0,95 ± 0,10) versus (0,87 ± 0,20) and to increase of IOL opacity only in some lenses but statistically significant in the average (6,37 ± 2,16)% versus value of (14,22 ± 5,87)%. In the explanted IOL we have documented structural changes of primarily hydrophobic raw material leading to property of hydrophilic one.

CONCLUSION

Some batches of AcryNovaTMPC 610Y were produced from raw material of poor quality which is the cause of its structural changes and its progressive opacification.

Reversible opacification of hydrophobic acrylic intraocular lens- two cases report

Background

The opacification of the intraocular lens (IOL) can cause significant visual deterioration. It is known that opacity of hydrophobic acrylic IOLs is rare. We report 2 cases of reversible optic opacification of hydrophobic acrylic intraocular lenses (Tecnis ZCB00, Abbott), observed within 2 months after uneventful cataract surgery.

Case presentation

Case 1: Uneventful cataract surgery was performed on the left eye of an 86-year-old diabetic man with chronic open-angle glaucoma. A hydrophobic acrylic intraocular lens (IOL; Tecnis ZCB00, Abbott, Lake Bluff, IL) was implanted in the bag. Eye drops containing 0.5% levofloxacin and 1.0% prednisolone were used after surgery along with topical anti-glaucoma medications. At 7 weeks postoperative, cloudy, concentric IOL opacification developed, accompanied by decreased visual acuity and increased intraocular pressure. However, the opacification completely disappeared after 9 weeks.

Case 2: Uneventful cataract surgery was performed on the left eye of a 72-year-old woman. A hydrophobic acrylic IOL (Tecnis ZCB00) was implanted in the bag. At 2 weeks postoperative, cloudy, concentric IOL opacification developed, accompanied by ocular discomfort. After 4 weeks, opacification and discomfort completely disappeared.

Conclusions

We observed two cases of completely reversible opacification of hydrophobic acrylic IOLs. The exact nature of the transient opacity remains unclear, but an inflammatory origin cannot be completely ruled out.

Posterior capsule opacification and neodymium:YAG rates with 2 single-piece hydrophobic acrylic intraocular lenses: three-year results

PURPOSE

To compare the incidence and intensity of posterior capsule opacification (PCO) between 2 similar 1-piece foldable hydrophobic acrylic intraocular lenses (IOLs) over 3 years.

SETTING

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

DESIGN

Randomized prospective patient- and examiner-masked clinical trial with intraindividual comparison.

METHODS

Patients with bilateral age-related cataract had cataract surgery and implantation of a Tecnis ZCB00 continuous-optic-edge IOL in 1 eye and an Acrysof SA60AT interrupted-optic-edge IOL in the other eye. Postoperative examinations were performed at 6 months and 3 years. Digital retroillumination images were taken of each eye. The amount of PCO (score 0 to 10) was assessed subjectively at the slitlamp and objectively using automated image-analysis software.

RESULTS

The study comprised 54 patients (108 eyes). The mean objective PCO score was 1.3 ± 1.7 (SD) for the continuous-optic-edge IOLs and 0.9 ± 1.3 for the interrupted-optic-edge IOLs (P=.10). Three years postoperatively, a neodymium:YAG (Nd:YAG) capsulotomy was performed in 26.1% of eyes with the continuous-optic-edge IOL and 21.7% with the interrupted-optic-edge IOL (P=.56). There was no significant difference in corrected distance visual acuity, capsulorhexis–IOL overlap, capsule folds, or anterior capsule opacification 3 years after surgery.

CONCLUSIONS

Both IOLs had comparable PCO and Nd:YAG rates 3 years postoperatively. The optimized barrier function of the continuous-optic-edge IOL and the material properties of the interrupted-optic-edge IOL seemingly outbalanced the effect on lens epithelial cell migration and proliferation beneath the optic.

Three-year incidence and factors associated with posterior capsule opacification after cataract surgery: The Australian Prospective Cataract Surgery and Age-related Macular Degeneration Study

PURPOSE

To assess 3-year incidence and associated factors of posterior capsule opacification (PCO) after phacoemulsification surgery.

DESIGN

Cohort study.

METHODS

A total of 1934 consecutive patients aged ≥64 years undergoing phacoemulsification surgery at Westmead Hospital were recruited, of whom 1495 (77.3%) had retroillumination anterior segment images taken of the surgical eyes after 1 month and at a further postoperative visit within 3 years. Severe PCO was defined if the view of the optic disc was obscured, or neodymium-yttrium-aluminum-garnet capsulotomy was performed. Cumulative incidence of PCO was estimated using Kaplan-Meier methods. Associations of PCO with surgeon groups and different types of implanted intraocular lenses (IOLs) were assessed, adjusting for age, sex, diabetes, and ethnicity.

RESULTS

Three-year cumulative incidence of PCO was 38.5% (95% confidence interval [CI] 36.1%-40.9%) among the 1495 patients, including 4.7% (95% CI 3.5%-5.8%) with severe PCO. PCO incidence was higher in: (1) eyes operated on by junior trainees (49%) compared to those by senior ophthalmologist surgeons (36%) (adjusted odds ratio [OR] 1.6, 95% CI 1.2-2.0); and (2) eyes with hydrophobic, 3-piece (either square-edged [51%, OR 2.3, 95% CI 1.4-3.6] or partial-round-edged [39%, OR 1.5, 95% CI 1.1-2.1]), or hydrophilic IOLs (64%, OR 2.9, 95% CI 1.9-4.4) compared to those with single-piece, square-edged, hydrophobic IOLs (34%), after additional adjustment for surgeon group.

CONCLUSIONS

Predominantly mild PCO occurred in one-third of eyes after phacoemulsification surgery. Possible predisposing factors associated with PCO development include surgery performed by ophthalmologic trainees and the use of hydrophilic or other hydrophobic IOLs apart from the single-piece, square-edged one.

Long-term Effect of 1-Piece and 3-Piece Hydrophobic Acrylic Intraocular Lens on Posterior Capsule Opacification

PURPOSE

To compare the intensity of posterior capsule opacification (PCO) between the 1-piece and 3-piece haptic designs of the foldable hydrophobic acrylic AcrySof intraocular lens (IOL) over a 5-year period.

DESIGN

Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison.

PARTICIPANTS

Fifty-two patients with bilateral age-related cataract (104 eyes).

METHODS

Each study patient had cataract surgery in both eyes and received a 1-piece AcrySof IOL in 1 eye and a 3-piece AcrySof IOL in the other eye. Follow-up examinations were performed at 1 week, 1 month, 6 months, and 1, 2, and 5 years. Digital retroillumination images were obtained of each eye. The amount of posterior capsule opacification (score range, 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software 1, 2, and 5 years after surgery.

MAIN OUTCOME MEASURE

Posterior capsule opacification score (scale, 0-10).

RESULTS

There was no significant difference between the 1-piece and 3-piece AcrySof IOL in best-corrected visual acuity, overlap of rhexis and IOL, capsular folds, anterior capsule opacification, and posterior capsule opacification (1-piece AcrySof PCO score, 1.7+/-1.7; 3-piece AcrySof PCO score, 1.3+/-1.4; P = 0.30).

CONCLUSIONS

Modification of the IOL haptic design of the sharp optic edged AcrySof IOL from a 3-piece to a 1-piece haptic design caused no significant change in PCO intensity and neodymium:yttrium-aluminium-garnet laser treatment rate 5 years after surgery.

The surgical management of cataract: barriers, best practices and outcomes

Cataract is the leading cause of blindness in the world. Cataract surgery has been shown by multiple studies to be one of the most cost-effective health interventions, and leads to a dramatic increase in quality of life and productivity for many patients. Though there has been marked improvement in the last several decades, surgical delivery services in developing nations are still suboptimal, and a large backlog in cataract cases continues to grow. To decrease this backlog, barriers to surgery, such as direct and indirect patient costs, geographic access to surgical facilities and surgeons, cultural factors, and patient education, must be addressed. In particular, access to services by women and rural patients needs to be improved. It is clear that extracapsular techniques are cost-effective and lead to better post-operative outcomes than intracapsular cataract extraction with aphakic correction. In addition, monitoring surgical outcomes is essential for improving the quality of surgical services. However, other issues regarding the delivery of cataract surgical services, including the role of average power intraocular lenses and the role of non-physician surgeons, are yet unresolved. Information about the true cost of surgery, including costs of surgeon training, equipment, and patient outreach programs, is needed so that the goal of self-sustaining programs may be obtained.

Long-term effect of optic edge design in a silicone intraocular lens on posterior capsule opacification

PURPOSE

To compare the posterior capsule opacification (PCO) inhibiting effect of the round anterior and sharp posterior optic edge profile of the Clariflex silicone intraocular lens (IOL) [AMO Inc, Santa Ana, California, USA] with that of the double-round edge profile of the SI40 (Phacoflex; AMO Inc, Santa Ana, California, USA) silicone IOL over a period of three years.

DESIGN

Prospective, randomized, double-masked, bilateral clinical trial.

METHODS

The study took place at the Department of Ophthalmology, Medical University of Vienna, Austria. Fifty-two patients with age-related cataracts (104 eyes) were included in the study. Each patient received an SI40 IOL (round edges) in one eye and a Clariflex IOL with OptiEdge (sharp posterior optic edge) in the other eye. Follow-up examinations were at one week, one month, six months, and one, two, and three years. Digital retroillumination images were taken of each eye. The amount of PCO was subjectively assessed with the slit-lamp and objectively assessed by automated image analysis software (the computer program Automated Quantification of After-Cataract [AQUA]; Vienna, Austria) one, two, and three years after surgery.

RESULTS

The Clariflex lens showed markedly less PCO at one, two, and three years after surgery. The mean AQUA PCO score was 1.39 for the SI40 and 0.56 for the Clariflex lens after one year, estimated at 1.64 and 0.57 after two years, and at 2.04 and 0.64, respectively, after three years (scale zero to 10; P < .001). The Nd:YAG laser capsulotomy rate was far higher in the SI40 group (Five cases vs one case at three years).

CONCLUSIONS

The sharp posterior optic edge profile of the Clariflex silicone IOL led to marked and consistently less PCO than the round-edged SI40 IOL one, two, and three years after surgery.

Quantitative Analysis of Posterior Capsule Opacification of Hydrophobic Acrylic Intraocular Lenses

Posterior capsule opacification (PCO) remains a common complication of modern cataract surgery, although both modification of materials used and changes in the intraocular lens (IOL) optic edge design have helped to decrease its incidence slightly. Recently, various kinds of quantitative methods have been developed for measuring PCO. The purpose of this study was to compare the quantitative analysis of PCO between different types of IOL designs. Patients enrolled in the study had age-related cataract and underwent uneventful cataract surgery and implantation of either the AcrySof MA30BA (Alcon) or the Sensor AR40e (AMO), which are differently designed hydrophobic acrylic IOLs with a sharp-edged optic design. Postoperative examination was performed at 6 months. Retroillumination photographs of each eye were obtained, and the degree of PCO was assessed using the Evaluation of Posterior Capsule Opacification (EPCO) system. Grade 1 PCO was noted in both the MA30BA and the AR40e groups. There was no significant difference in the mean PCO score between the MA30BA and AR40e groups. Although the sharp-edged optic designs of both IOLs might similarly inhibit PCO at 6 months, a long-term follow-up period is needed to determine if any PCO differences occur between these 2 hydrophobic acrylic IOLs.

Cumulative neodymium:YAG laser rates after bag-in-the-lens and lens-in-the-bag intraocular lens implantation

PURPOSE

To study the cumulative neodymium:YAG (Nd:YAG) laser rate after bag-in-the-lens implantation (Morcher 89A) and lens-in-the-bag implantation (Morcher 92S) of 2 intraocular lenses (IOLs) of the same biomaterial.

SETTING

Department of Ophthalmology, University Hospital of Antwerp, Edegem, Belgium.

METHODS

This study comprised 100 eyes of 87 patients who had the bag-in-the-lens IOL implantation between January 2000 and August 2004. The postoperative follow-up ranged between 17 and 72 months. One hundred eyes of 94 patients of the same age and with the same follow-up period received the lens-in-the-bag IOL. The cumulative Nd:YAG laser frequency rates in both groups were calculated, and the cumulative incidence rates were defined by Kaplan-Meier survival analysis.

RESULTS

No Nd:YAG laser capsulotomy was performed in eyes having bag-in-the-lens IOL implantation. A laser capsulotomy was performed in 20 eyes having lens-in-the-bag IOL implantation; the cumulative frequency in this group was 2% at 1 year and 20% at 71 months, with a plateau beginning at 42 months. The cumulative incidence rate of Nd:YAG posterior capsulotomy was approximately 2% at 1 year, increasing to approximately 28% at 42 months.

CONCLUSIONS

The cumulative Nd:YAG laser rate after bag-in-the-lens implantation was zero. A zero rate has not been reported with lens-in-the-bag implantation of an IOL of the same biomaterial or of other biomaterials, as published in the literature. Thus, it can be concluded that the bag-in-the-lens implantation technique has 100% effectiveness against posterior capsule opacification.

After-cataract evaluation after using balanced salt solution, distilled deionized water, and 5-fluorouracil with a sealed-capsule irrigation device in the eyes of 4-week-old rabbits

PURPOSE

To evaluate the Perfect Capsule sealed-capsule irrigation device (Milvella Pty., Ltd.) using 3 substances in young rabbit eyes.

SETTING

St. Erik's Eye Hospital, Stockholm, Sweden.

METHODS

Thirty 4-week-old rabbits had clear lens extraction in both eyes. In 1 randomly selected eye, the Perfect Capsule was applied and the lens capsule was irrigated for 5 minutes with 1 of 3 substances: balanced salt solution (BSS), distilled deionized water (DDW), or 5-fluorouracil (5-FU) 50 mg/mL. In the other eye, no sealed capsule irrigation was used. Forty days postoperatively, the animals were killed and the eyes fixed in formalin for histologic analysis. After-cataract was evaluated in 3 ways: clinically, from photographs, and histologically. Central posterior capsule thickness was evaluated using a microscope, camera, and computer.

RESULTS

The Perfect Capsule sealed-capsule irrigation system could be used in all selected eyes. The vacuum to the anterior capsule was tight, and the system was sealed in all eyes. After-cataract developed in the BSS group and DDW group, but not in the 5-FU group. The 5-FU group had significantly less after-cataract than the other 2 groups (P<.05). There was no difference between the groups in capsule thickness.

CONCLUSIONS

The Perfect Capsule sealed-capsule irrigation system could be used in small eyes. Distilled deionized water did not prevent after-cataract in rabbit eyes with highly proliferative cells, but 5-FU was effective in preventing after-cataract.

Modification of the surface properties of a lens material to influence posterior capsular opacification

PURPOSE

To study the effect of surface properties of materials on cellular behaviour and the formation of posterior capsular opacification (PCO).

METHODS

Polymethylmethacrylate, silicone and a hydrophobic acrylic were plasma treated and used in tissue culture. The changes in surface properties were quantified by dynamic contact angle measurements. Bovine lens epithelial cells (BLECs) were seeded onto these materials and cultured for 1 month. Serial photographs were taken. The cells were then fixed and stained to facilitate counting.

RESULTS

Plasma treatment significantly increased the hydrophilicity of surfaces. BLECs grew on all surfaces but significantly more cells adhered to the treated than the untreated surfaces. On the untreated surfaces the BLECs had a fibroblastic morphology whereas on the treated surfaces the cells maintained their epithelial morphology.

CONCLUSIONS

Posterior capsular opacification is a form of wound healing and the behaviour of lens epithelial cells is central to its progression. Emphasis has been on the elimination of residual lens epithelial cells to combat PCO. This study demonstrated that the phenotype of BLECs was influenced by the surface properties of the intraocular lens materials. Gas plasma treatment of the materials increased their hydrophilicity and allowed the adhered BLECs to maintain their normal epithelial morphology. We believe that controlled growth of lens epithelial cells may reduce the incidence of PCO.

Comparison of posterior capsule opacification between fellow eyes with two types of acrylic intraocular lens

PURPOSE

To compare the degree of posterior capsule opacification (PCO) and visual function between fellow eyes that received two different types of hydrophobic acrylic intraocular lenses (IOLs).

METHODS

Forty-five patients underwent bilateral phacoemulsification and implantation of an Alcon AcrySof IOL (MA60AC) in one eye and an AMO Sensar IOL (AR40e) in the fellow eye. The PCO density value was measured using the Scheimpflug videophotography system at 1, 6, 12, and 24 months after surgery. The incidence of eyes that required a neodymium:YAG (Nd:YAG) laser capsulotomy, visual acuity, and contrast sensitivity with and without a glare source were also examined.

RESULTS

The mean PCO value did not show a significant increase in either the AcrySof MA60AC or Sensar AR40e IOL groups, and was similar between the two groups throughout the 24-month follow-up period. The incidence of Nd:YAG laser capsulotomy was also the same between the groups. No significant difference was found in mean visual acuity between the two IOL groups during the follow-up, and there was no significant difference in photopic or mesopic contrast visual acuity with and without a glare source at 1 and 24 months after surgery.

CONCLUSION

The degree of PCO in eyes with an AcrySof IOL are almost the same as that in eyes with a Sensar IOL, with the results that visual acuity and contrast sensitivity with and without glare are similar.

Nd:YAG capsulotomy rates after use of the AcrySof acrylic three piece and one piece intraocular lenses

BACKGROUND/AIM

Acrylic lens size and shape may influence the rate of posterior capsule opacification (PCO) and need for Nd:YAG capsulotomy. The aim of this study is to compare the Nd:YAG capsulotomy rate of the three piece acrylic/PMMA AcrySof MA series lens with the one piece acrylic AcrySof SA series lens.

METHODS

434 eyes of 329 patients who had cataract extraction and implantation of one of four types of intraocular lenses (IOLs) were evaluated for rate of Nd:YAG capsulotomy. 176 eyes received the acrylic AcrySof MA30AC IOL, 71 eyes the acrylic AcrySof MA60AC IOL, 45 eyes the acrylic AcrySof SA30AL IOL, and 142 eyes the acrylic AcrySof SA60AT IOL.

RESULTS

The rates of Nd:YAG capsulotomy with the three piece IOL (MA30AC/MA60AC) and the one piece IOL (SA30AL/SA60AT) were 1.2% and 2.1% at 6 months, 2.8% and 5.9% at 12 months, and 3.6% and 7.5% at 24 months, respectively. The incidence of Nd:YAG capsulotomy was higher in patients who received the one piece IOL (p=0.01, log rank test). There was no difference in Nd:YAG capsulotomy rates when comparing lens optic size, age, sex, history of pars plana vitrectomy, and diabetes mellitus.

CONCLUSIONS

This study shows a greater incidence of Nd:YAG capsulotomy in patients who receive one piece acrylic AcrySof lenses when compared to those who receive three piece acrylic AcrySof lenses.

Prospective evaluation of phacoemulsification in adults younger than 50 years

PURPOSE

To evaluate intraoperative performance and long-term outcome of phacoemulsification in patients younger than 50 years.

SETTING

Iladevi cataract and IOL Research Centre, Ahmedabad, India.

METHODS

A prospective observational study was conducted comprising 54 patients (35 men and 19 women) under age 50 who had phacoemulsification. Preoperative evaluation included specular microscopy. Phacoemulsification with implantation of an AcrySof MA30BA intraocular lens (IOL) was performed. Intraoperatively, peripheral extension of capsulorhexis, intraoperative posterior capsule opacification (PCO; plaque), and serious complications (eg, posterior capsule rupture, vitreous loss) were noted. Postoperatively, endothelial cell loss, postoperative PCO, neodymium:YAG (Nd:YAG) laser posterior capsulotomy rate, and best corrected visual acuity (BCVA) were assessed for 3 years. Patients with intraoperative PCO were analyzed separately.

RESULTS

Mean patient age was 42.7 years +/- 5.2 SD (men) and 43.1 +/- 3.25 years (women). Continuous curvilinear capsulorhexis was achieved in 49 patients (90.7%). Intraoperative PCO was present in 14 (25.92%) patients. An Nd:YAG laser posterior capsulotomy was performed in 4 patients (28.5%). Posterior capsule rupture leading to vitreous loss occurred in 1 patient (1.85%). At 3-year follow-up, endothelial cell loss was 5.9%. Postoperative PCO developed in 8 patients (22.2%), and Nd:YAG laser posterior capsulotomy was performed in 5 patients (13.8%). The BCVA was > or = 20/40 in 47 patients (94%).

CONCLUSION

Young patients pose a challenge in creating a capsulorhexis and display significant incidence of intraoperative and postoperative PCO.

Effect of cataract surgery incision location and intraocular lens type on ocular aberrations

PURPOSE

To determine whether Hartmann-Shack wavefront sensing detects differences in optical performance in vivo between poly(methyl methacrylate) (PMMA) and foldable acrylic intraocular lenses (IOLs) and between clear corneal and scleral tunnel incisions and whether optical differences are manifested as differences in visual performance.

SETTING

Department of Optometry, University of Bradford, West Yorkshire, United Kingdom.

METHODS

This study comprised 74 subjects; 17 were phakic with no ocular pathology, 20 had implantation of a Pharmacia 722C PMMA IOL through a scleral tunnel, 21 had implantation of an Alcon AcrySof IOL through a scleral tunnel, and 16 had implantation of an AcrySof IOL through a corneal incision. Visual acuity and contrast sensitivity testing, ocular optical quality measurement using Hartmann-Shack wavefront sensing, and corneal surface measurement with a videokeratoscope were performed in all cases.

RESULTS

There were significant differences between groups in the total root-mean-square (RMS) wavefront aberration over a 6.0 mm pupil (F=3.91; degrees of freedom=3,70; P<.05) mediated at the 4th-order RMS, specifically spherical and tetrafoil aberrations. The PMMA-scleral group had the least aberrations and the AcrySof-corneal group the most. For a 3.5 mm diameter pupil, the total higher-order RMS wavefront aberration was not significantly different between the groups (P>.05). There were no differences between groups in corneal shape, visual acuity, or contrast sensitivity.

CONCLUSIONS

Implantation of the spherical PMMA IOL led to a slight reduction in total wavefront aberration compared to phakic eyes. AcrySof IOLs induced more aberrations, especially spherical aberration. Corneal-based incisions for IOL implantation compounded this increase. Studies of the optical performance of IOLs in vivo should use wavefront sensing as the main outcome measure rather than visual measures, which are readily confounded by multiple factors.

Long-term effect of optic edge design in an acrylic intraocular lens on posterior capsule opacification

PURPOSE

To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) with that of the double-round edge design of the Sensar AR40 IOL over a period of 3 years.

SETTING

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

METHODS

Fifty-three patients with bilateral age-related cataract (106 eyes) were included in this randomized prospective bilateral patient- and examiner-masked clinical trial with intraindividual comparison. Each study patient had cataract surgery in both eyes and received a Sensar AR40 IOL (anterior and posterior round optic edges) in 1 eye and a Sensar OptiEdge AR40e IOL (round anterior and sharp posterior optic edge) in the other eye. Follow-up examinations were at 1 week, 1 and 6 months, and 1, 2, and 3 years. Digital retroillumination images were taken of each eye. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software (AQUA) 1, 2, and 3 years after surgery.

RESULTS

The sharp-edged AR40e lens showed significantly less regeneratory and fibrotic PCO 1, 2, and 3 years after surgery. The mean AQUA PCO score was 2.18 for the AR40 and 1.00 for the AR40e lens after 1 year; 2.94 and 1.56 after 2 years, and estimated at 3.13 and 1.77, respectively, after 3 years (scale 0 to 10; P<.001). The neodymium:YAG laser capsulotomy rate was significantly higher in the AR40 group. The AR40e lens also led to less peripheral fibrotic PCO. There was no significant difference in complaints concerning edge glare between the groups.

CONCLUSION

Compared with the AR40 IOL, the sharp posterior optic edge design of the Sensar OptiEdge AR40e IOL led to significantly less PCO 1, 2, and 3 years postoperatively. In contrast with most past studies on PCO-preventative factors, this study varied only 1 parameter, namely the optic edge design, and the main outcome measure (PCO) was assessed with an objective image-analysis system.

Comparison of the Long-term Clinical Results of Hydrophilic and Hydrophobic Acrylic Intraocular Lenses

This study was performed to compare the incidence of posterior capsular opacity (PCO) and refractive errors between hydrophilic (ACR6D, Corneal) and hydrophobic (MA60BM, AcrySof) acrylic intraocular lenses (IOLs) over a 3-year follow-up after phacoemulsification surgery. The patients with AcrySof implanted in one eye and Corneal in the other eye were categorized as Group 1 (n=28), while those with one or both eyes implanted with IOLs of the same kind were categorized as Group 2 (AcrySof, n=90; Corneal, n=95). Refractive errors were evaluated at 3 months and 3 years postoperatively. The incidence of visually significant PCO was investigated 3 years postoperatively. Postoperative refractive values at 3 months were not significantly different between the two groups. However, refractive values at 3 years were significantly different between two IOLs in both groups [AcrySof -0.37+/-0.43D, Corneal -0.62+/-0.58D in Group 1 (p=0.04); AcrySof -0.38+/-0.52, Corneal -0.68+/-0.54 in Group 2 (p<0.01)]. The incidence of visually significant PCO was 14% and 32% in Group 1, and 13% and 28% in Group 2, for the AcrySof and Corneal implants, respectively. The incidence of visually significant PCO of hydrophilic acrylic IOLs was higher than that of hydrophobic acrylic IOLs in the 3-year follow-up. The postoperative 3-year refractive value of Corneal showed myopic shift.

Evaluation of a human capsular bag model for secondary cataract determination after intraocular lens implantation

PURPOSE

To investigate the effect of different intraocular lenses (IOLs) on lens epithelial cells (LECs) and on human capsular bags in vitro and to evaluate the transferability of this model to clinical situations.

METHODS

Sham cataract surgery, including IOL-into-the-bag implantation, was performed on 38 donor eyes after removal of the cornea. The capsular bag including the IOL was removed, pinned on a culture dish, covered with medium, and incubated. Two different IOLs were compared per pair of donor eyes. In each pair of donor eyes, the two different IOLs to be compared were implanted individually into capsular bags. The time required for complete coverage of the posterior capsule by a confluent monolayer of LECs was documented. The following IOLs were compared: three-piece acrylic IOLs of different sizes and single-piece polymethylmethacrylate (PMMA) versus acrylic IOLs.

RESULTS

A complete monolayer of LECs on the posterior capsule was observed to form at times varying from 8 days (PMMA IOLs) to more than 60 days (three-piece hydrophobic acrylic IOLs). A significant difference between PMMA IOLs and hydrophobic acrylic IOLs was found.

CONCLUSIONS

The human capsular bag model employed allows short-term evaluation of secondary cataract formation for different IOLs. This model's correlation with clinical results is good.

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.

A prospective, randomised comparison of single and three piece acrylic foldable intraocular lenses

AIMS

To compare the postoperative performance of single and three piece acrylic foldable intraocular lenses (IOLs).

METHODS

20 patients underwent bilateral cataract surgery with a single piece SA30AL IOL in one eye and a three piece MA30BA IOL in the other eye. The eyes were randomly assigned to either a single or three piece lens. The amount of IOL decentration and tilt, area of anterior capsule opening, and degree of posterior capsule opacification were measured using the Scheimpflug anterior segment analysis system (Nidek EAS-1000). Visual acuity and contrast sensitivity were examined. Measurements were performed by masked examiners before and 1 day, 1 week, 1, 3, 6, and 18 months after surgery.

RESULTS

There were no significant differences between the two groups (p>0.05, paired t test) in the amount of IOL decentration, IOL tilt, area of anterior capsule opening, degree of posterior capsule opacification, best corrected visual acuity, and contrast sensitivity throughout the 18 month follow up period.

CONCLUSION

The single and three piece acrylic foldable IOLs are equally stable in the eye after surgery.

Visual axis opacification after AcrySof intraocular lens implantation in children

PURPOSE

To evaluate visual axis opacification after AcrySof intraocular lens (IOL) (Alcon) implantation in pediatric eyes.

SETTING

Iladevi Cataract and IOL Research Centre, Ahmedabad, India.

METHODS

This prospective study evaluated 103 consecutive eyes of 72 children with congenital cataract. Two groups were formed based on age at surgery: Group 1, younger than 2 years, and Group 2, older than 2 years. All eyes in Group 1 (n = 37) had primary posterior continuous curvilinear capsulorhexis (PCCC) with anterior vitrectomy. In Group 2 (n = 66), management of the posterior capsule was assigned randomly to no PCCC (Group 2A, n = 37) or PCCC (Group 2B, n = 29). The PCCC group was further randomized into 2 subgroups: no vitrectomy (Group 2BN, n = 14) or vitrectomy (Group 2BV, n = 15). The primary outcome measures were visual axis opacification and the resulting need for a secondary procedure. Statistical analysis was performed using SPSS for Windows (version 11.0.1).

RESULTS

The mean age of the patients was 5.2 years +/- 5.0 (SD) (range 0.2 to 16.0 years) and the mean follow-up, 2.3 +/- 0.9 years (range 1.0 to 4.0 years). Overall, 41 eyes (39.8%) developed visual axis opacification and 14 (13.6%) required secondary intervention. In Group 1, 4 eyes (10.8%) developed visual axis opacification and 3 (8.1%) had a secondary pars plana vitrectomy. In Group 2A, 31 eyes (83.8%) developed posterior capsule opacification (PCO) and 10 eyes (27.7%) had secondary intervention. Children 8 years or younger at the time of surgery developed significantly greater PCO than older children (P =.01). Five eyes (37.5%) in Group 2BN had opacification of the anterior vitreous face, 1 of which required a secondary procedure. One eye (6.7%) in Group 2BV had visual axis opacification that did not require a secondary procedure.

CONCLUSIONS

AcrySof IOL implantation with appropriate management of the posterior capsule maintained a clear visual axis in 60.2% of eyes. Of the 39.8% of eyes with visual axis opacification, 13.6% had visually significant opacification and required a secondary procedure.

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.

Opacification of the visual axis after cataract surgery and single acrylic intraocular lens implantation in the first year of life

PURPOSE

To report the incidence and risk factors for secondary surgical intervention to treat visual axis opacification (VAO) after cataract surgery and acrylic intraocular lens (IOL) implantation during the first year of life.

METHODS

A retrospective review of 29 eyes of 20 patients receiving a hydrophobic acrylic (AcrySof; Alcon, Fort Worth, TX) IOL implantation was conducted. All eyes underwent primary posterior capsulectomy and anterior vitrectomy. Statistical analysis was performed using SPSS for Windows (SPSS, Chicago, IL).

RESULTS

Average age at surgery was 4.8 +/- 3.7 months, and average follow-up was 33.4 +/- 16.1 months. Eleven of 29 (37.9%) eyes developed VAO requiring secondary surgical intervention at a median of 4.8 months (95% confidence interval 3.4 to 6.2). Average age at surgery for eyes that subsequently opacified was 3.8 +/- 3.0 months compared with 5.4 +/- 4.0 months for those whose visual axis remained clear (P = 0.26). The relative risk of subsequent VAO surgery was 2.7 for primary surgery performed at or before the first 6 months of life. Opacification was significantly related to eyes with associated ocular anomalies (eg, anterior segment dysgenesis, iris hypoplasia, or persistent fetal vasculature) with a relative risk of 8.6 (P < 0.001). Proliferation of cortex was the most common form of VAO, followed by mixed-type with predominantly fibrous, fibrous alone, or Elschnig pearls. When secondary surgery was required, it occurred primarily during the first 6 months (ie, 9 of 11 patients) after the initial cataract surgery.

CONCLUSIONS

When cataract and IOL surgery was undertaken within the first year of life, a secondary surgical procedure was required in 37.9% of eyes to maintain a clear visual axis. Most secondary surgery for VAO occurred within the first 6 months after surgery. Postoperative opacification was most common in eyes with associated ocular anomalies.

Cumulative probability of neodymium: YAG laser posterior capsulotomy after phacoemulsification

PURPOSE

To retrospectively analyze the cumulative probability of neodymium:YAG (Nd:YAG) laser posterior capsulotomy after phacoemulsification and to evaluate the risk factors.

SETTING

Ando Eye Clinic, Kanagawa, Japan.

METHODS

In 3997 eyes that had phacoemulsification with an intact continuous curvilinear capsulorhexis, the cumulative probability of posterior capsulotomy was computed by Kaplan-Meier survival analysis and risk factors were analyzed using the Cox proportional hazards regression model. The variables tested were sex; age; type of cataract; preoperative best corrected visual acuity (BCVA); presence of diabetes mellitus, diabetic retinopathy, or retinitis pigmentosa; type of intraocular lens (IOL); and the year the operation was performed. The IOLs were categorized as 3-piece poly(methyl methacrylate) (PMMA), 1-piece PMMA, 3-piece silicone, and acrylic foldable.

RESULTS

The cumulative probability of capsulotomy after cataract surgery was 1.95%, 18.50%, and 32.70% at 1, 3, and 5 years, respectively. Positive risk factors included a better preoperative BCVA (P =.0005; risk ratio [RR], 1.7; 95% confidence interval [CI], 1.3-2.5) and the presence of retinitis pigmentosa (P<.0001; RR, 6.6; 95% CI, 3.7-11.6). Women had a significantly greater probability of Nd:YAG laser posterior capsulotomy (P =.016; RR, 1.4; 95% CI, 1.1-1.8). The type of IOL was significantly related to the probability of Nd:YAG laser capsulotomy, with the foldable acrylic IOL having a significantly lower probability of capsulotomy. The 1-piece PMMA IOL had a significantly higher risk than 3-piece PMMA and 3-piece silicone IOLs.

CONCLUSIONS

The probability of Nd:YAG laser capsulotomy was higher in women, in eyes with a better preoperative BCVA, and in patients with retinitis pigmentosa. The foldable acrylic IOL had a significantly lower probability of capsulotomy.

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.

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

PURPOSE

To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) (Allergan Surgical) with that of the round-edged design of the Sensar AR40 IOL. Setting Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This prospective randomized patient- and examiner-masked study comprised 106 eyes of 53 patients with bilateral age-related cataract. Each patient had cataract surgery in both eyes and received an AR40 IOL in 1 eye and an AR40e IOL in the other eye. Postoperative examinations were at 1 week, 2 and 6 months, and 1 year. Digital slitlamp and digital retroillumination images of each eye were taken. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software.

RESULTS

The AR40e group had significantly less regeneratory and fibrotic PCO 1 year after surgery. The mean automated image-analysis software PCO score (scale 0 to 10) was 2.19 in the AR40 group and 1.10 in the AR40e group (P <.001). The AR40e group had less peripheral fibrotic PCO. There was no significant difference in patient-reported edge glare between the 2 IOL groups.

CONCLUSIONS

The sharp-edged design of the Sensar OptiEdge AR40e IOL led to significantly less PCO than the round-edged AR40 IOL 1 year postoperatively.