Update on fixation of rigid and foldable posterior chamber intraocular lenses. Part II: Choosing the correct haptic fixation and intraocular lens design to help eradicate posterior capsule opacification

Influence of total intraocular lens diameter on efficacy and safety for in the bag cataract surgery

CONTEXT

Intraocular lenses with variable total diameter are supposed to fit better in the capsular bag and lead to fewer complications.

AIMS

This study aims to investigate the efficacy and the safety of an intraocular lens model with variable total diameter.

SETTINGS AND DESIGN

Prospective randomized intraindividual study.

SUBJECTS AND METHODS

Thirty-two eyes of sixteen patients with bilateral age-related cataract received standard cataract surgery with implantation of an intraocular lens with a standard diameter in one eye (Quatrix®, Group A) and with a variable total diameter in the fellow eye (Quatrix Evolutive®, Group B). Primary study endpoints included evaluation of refraction stability and posterior capsule opacification (PCO) over a follow-up period of 6 months.

STATISTICAL ANALYSIS USED

SPSS (Version 19.0) was used for statistical analysis.

RESULTS

Uncorrected and corrected distant visual acuity after 6 months were 0.24 and 0.1 LogMAR in Group A and 0.23 and 0.09 LogMAR in Group B, respectively. The objective and manifest spherical equivalent (OSE, MSE) 6 months postoperatively were + 0.65 D and + 0.62 D in Group A compared to + 0.33 D and + 0.33 D in Group B respectively (P = 0.665 for OSE, P = 0.208 for MSE). PCO-index increased statistically significant in both groups (P = 0.004 in Group A, P = 0.046 in Group B), but the difference of PCO-index between both groups was not statistically significant (P = 0.569).

CONCLUSIONS

An intraocular lens with a variable total diameter shows good visual outcomes and safety performance as well as same outcomes concerning postoperative refractive stability and development of PCO compared to an intraocular lens with standard total diameter.

Biomaterial Influence on Intraocular Lens Performance: An Overview

There is strong evidence that the IOL material is the factor having the greatest impact on posterior capsule opacification (PCO), anterior capsule opacification (ACO) development, and glistening formation after cataract surgery, even though there are other IOL features—such as haptic material and design and edge and optic design—that also have some influence. We reviewed the published literature describing the adverse events that are mainly related to the intraocular lens (IOL) material, such as PCO, ACO, and the subsequent capsule contraction, as well as glistening formation. The adverse events presented in this overview are the most common ones in clinical practice, and therefore, they are generally included in the clinical protocols for IOL evaluation.

The Complexities of Negative Dysphotopsia

The appearance of a dark shadow in the temporal periphery, otherwise known as negative dysphotopsia, continues to be a problem for some patients after routine uncomplicated cataract surgery. Etiologies include type and design of intraocular lens (IOL), anatomical features and dimensions of the eye, pupil size, angle kappa, relationship of the optic to the anterior capsule, and the position of the optic/haptic junction of the IOL. Although the primary etiology remains controversial, it is clear that the cause is multifactorial. All of the factors should be considered when attempting to prevent or treat this phenomenon.

Negative dysphotopsia: A perfect storm

The objective of this review was to provide a summary of the peer-reviewed literature on the etiologies of negative dysphotopsia that occurs after routine cataract surgery. A search of PubMed, Google Scholar, and Retina Medical identified 59 reports. Negative dysphotopsia has been associated with many types of intraocular lenses (IOLs), including hydrophobic and hydrophilic acrylic, silicone, and 1-piece and 3-piece designs. Proposed etiologies include edge design, edge smoothness, edge thickness, index of refraction of the IOL, pupil size, amount of functional nasal retina, edema from the clear corneal incision, distance between the iris and IOL, amount of pigmentation of the eye, corneal shape, prominent globe and shallow orbit, and interaction between the anterior capsulorhexis and IOL. Treatments include a piggyback IOL, reverse optic capture, dilation of the pupil, constriction of the pupil, neodymium:YAG capsulotomy of the nasal portion of the anterior capsule, IOL exchange with round-edged optics, and time alone. This review summarizes the findings.

FINANCIAL DISCLOSURE

Dr. Henderson is a consultant to Alcon Laboratories, Inc., Abbott Medical Optics, Inc., Bausch & Lomb, and Genzyme Corp. Neither author has a financial or proprietary interest in any material or method mentioned.

Hydrophobic acrylic versus polymethyl methacrylate intraocular lens implantation following cataract surgery in the first year of life

PURPOSE

To evaluate complication rates following implantation of hydrophobic acrylic versus polymethyl methacrylate (PMMA) intraocular lens (IOL) with cataract surgery in infants.

METHODS

Records of children undergoing cataract surgery with IOL implantation in first year of life were retrospectively reviewed. Infants were divided into two groups--hydrophobic acrylic IOLs were implanted in group A, and PMMA IOLs in group B. Outcome measures included incidence of complications, additional surgical procedures, and refractive error changes.

RESULTS

One hundred and thirteen eyes of 113 children (75 males) with mean age of 6.49 ± 3.56 months were included. Group A included 62 eyes, and group B included 51 eyes. The two groups did not differ significantly in terms of age and axial length. There was no significant difference between the groups for incidence of posterior capsular opacification (PCO), pupillary membranes, glaucoma, fibrin on IOL surface or IOL malposition (p = 0.09). Development of PCO was delayed in group A (p = 0.049). Thirteen eyes of group A and 18 eyes of group B required additional surgical intervention (p = 0.20) in the follow-up visits.

CONCLUSION

Comparable complications may be expected in infants with PMMA and hydrophobic acrylic lenses. Children implanted with PMMA IOLs may require earlier surgical re-intervention for PCO.

Efficacy of COX-2 inhibitors in controlling inflammation and capsular opacification after phacoemulsification cataract removal

OBJECTIVE

To evaluate the efficacy of 0.9% bromfenac (Xibrom™) or a celecoxib-impregnated intraocular lens (celecoxib-IOL) compared with 1% prednisolone acetate (PA) in controlling postoperative inflammation and posterior capsule opacification (PCO).

ANIMAL STUDIED

Fifty-nine dogs undergoing cataract extraction by phacoemulsification.

PROCEDURE

Bilateral patients received bromfenac or celecoxib-IOL plus PA in one eye, and PA in the contralateral eye. Unilateral patients received bromfenac or PA. Complete ophthalmic examination including tonometry, slit-lamp grading of flare and PCO, and digital image acquisition for masked PCO evaluation was performed within 24 h and 1, 4, 12, 24, and 56 weeks following surgery.

RESULTS

Celecoxib-IOL/PA-treated eyes had significantly less flare than PA-treated eyes, which had significantly less flare than bromfenac-treated eyes 24 h postoperatively. There was no significant difference in intraocular pressure (IOP) postoperatively, or at 1, 24, or 56 weeks. Celecoxib-IOL/PA-treated eyes had significantly lower IOP measurements than bromfenac and PA-treated eyes at 4 and 12 weeks. There was no significant difference in PCO level between groups using slit-lamp biomicroscopy at any time point. Masked evaluation of digital images revealed significantly less PCO in celecoxib-IOL/PA- vs. bromfenac-treated eyes at 4 weeks, and in bromfenac- vs. PA-treated eyes at 56 weeks.

CONCLUSIONS

Eyes receiving celecoxib-IOL/PA had better initial control of inflammation. Bromfenac was equally effective compared with PA in controlling inflammation. There was no association between COX-2 inhibitor administration and ocular hypertension. Celecoxib-IOL/PA-treated eyes showed better initial control of PCO (up to 12 weeks), while eyes receiving bromfenac had better long-term control of PCO (56 weeks).

Effect of heparin coating of a foldable intraocular lens on inflammation and capsular bag performance after cataract surgery

PURPOSE

To evaluate the effect of a heparin-coated foldable intraocular lens (IOL) on postoperative flare in high-risk patients.

SETTING

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN

Randomized clinical trial.

METHODS

This study included patients with diabetes mellitus (DM), pseudoexfoliation syndrome (PXF), or both scheduled for cataract surgery in both eyes. One eye received a coated IOL (Polylens EC-1YH PAL) and the other eye, an uncoated control IOL (Polylens EC-1Y PAL). Aqueous flare measurements were taken using a laser flare meter (FM-600, Kowa) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively. Visual acuity and anterior (ACO) and posterior (PCO) capsule opacification were assessed, and IOL centration and tilt were measured with a Purkinje meter.

RESULTS

Eighty eyes of 40 patients were included in the study; 64 eyes of 32 patients completed the study. The mean flare values (photons/ms) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively were 6.98 ± 3.71 (SD), 19.14 ± 18.90, 16.62 ± 25.33, 10.33 ± 9.70, 8.74 ± 4.64, respectively, with the coated IOL and 8.65 ± 5.73, 22.08 ± 16.23, 13.44 ± 13.71, 7.50 ± 4.11, and 7.03 ± 3.70, respectively, with the control IOL. No significant differences were found in flare, visual acuity, ACO, PCO, tilt, or centration between the coated IOL and the control IOL at any timepoint.

CONCLUSION

No significant differences in flare or capsule performance were found between the coated IOL and control IOL.

Modern cataract surgery: unfinished business and unanswered questions

We summarize information, based on clinicopathologic studies over the past decade, on various cataract intraocular lens (IOL) procedures and modern "specialized" IOLs, that will help surgeons continuously improve long-term results for cataract patients. Although most operations do initially provide excellent refractive correction and visual rehabilitation, late complications occur. These sometimes are missed because they are outside of the routine period of follow-up care. We have tried to determine if the various techniques and IOLs truly deliver the long-term results that we desire. Most safety and efficacy information is derived from the manufacturer and is passed through the U.S. Food and Drug Administration (FDA). This is often based on limited, relatively short-term observations made by the manufacturer. After a lens receives FDA approval, there are few means to assess the outcome of each procedure and lens years later. We rarely hear of a 10- or 20-year follow-up study. We have found that one of the best means to assess long-term results is pathologic analyses. We discuss recently studied aspects of pathologic reactions, such as posterior capsule opacification, intracapsular fibrosis, glistenings, intralenticular opacification, and other issues with the various IOL platforms; we then present a clinicopathological overview of tissues and IOLs from our database. These include hydrophobic and hydrophilic acrylic designs, plate lenses, and a dual optic lens.

Evaluation of Posterior Capsular Opacification following Phacoemulsification, Extracapsular and Small Incision Cataract Surgery

BACKGROUND

Posterior capsular opacification is the most common complication of modern cataract surgery.

METHODS

A prospective study was conducted on 150 patients (150 eyes) out of which 50 eyes each underwent cataract surgery by extracapsular cataract extraction, small incision cataract surgery and phacoemulsification technique. On postoperative follow up posterior capsular opacification and Neodymium: Yttrium Aluminium Garnet laser capsulotomy rate was evaluated.

RESULT

Posterior capsular opacification rate was significantly less (p=0.03) in eyes which had undergone phacoemulsification as compared to extracapsular cataract extraction. However capsulotomy rate was not statistically significant after comparison of the three surgical techniques of cataract surgery.

CONCLUSION

Posterior capsular opacification following cataract surgery can be minimized by the use of small incision cataract surgery and phacoemulsification.

Comparison of posterior capsule opacification development with 3 intraocular lens types: five-year prospective study

PURPOSE

To compare the effects of hydrophobic acrylic, silicone, and heparin-surface-modified poly(methyl methacrylate) (HSM PMMA) intraocular lenses (IOLs) on posterior capsule opacification (PCO).

METHODS

In this 5-year prospective study, the same surgeon performed standard phacoemulsification in patients who were randomized to implantation of a round-edged HSM PMMA IOL (809C), a round-edged silicone IOL (SI-40NB), or a sharp-edged hydrophobic acrylic IOL (AcrySof MA60BM). The neodymium:YAG capsulotomy rate was recorded. To evaluate PCO and the position of the anterior capsulorhexis, retroillumination digital photographs were taken 5 years postoperatively and analyzed using the POCOman computer-analysis system.

RESULTS

After 5 years, there was no significant difference in the fraction or severity of PCO between the silicone IOLs and acrylic IOLs (both P =1.0). The silicone IOL group had a significantly higher capsulotomy rate (29%) than the acrylic IOL group (8%) (P=.0068). The HSM PMMA IOL group had a significantly higher PCO fraction, severity, and capsulotomy rate (54%) than the silicone and acrylic groups. In all eyes, the fraction (P=.0076) and severity (P=.0081) of PCO were statistically significantly higher when the anterior capsulorhexis was partly decentered than when it was completely on the optic; within each IOL group, there was no significant difference.

CONCLUSION

After 5 years, there was no significant difference in the semiquantitative evaluation of PCO between the sharp-edged acrylic IOL and round-edged silicone IOL. Eyes with the HSM PMMA IOL had more PCO than eyes with the other IOLs.

Spontaneous closure of anterior capsule tear

We report a case of anterior capsule tear that was closed spontaneously by fibrotic tissue during the postoperative period. The tear was inadvertently created during intraocular lens (IOL) implantation in the capsular bag. The IOL remained stable in the postoperative period, with excellent centration and no compromise in vision.

Optical coherence tomography evaluation of posterior capsule opacification related to intraocular lens design

PURPOSE

To evaluate posterior capsule opacification (PCO) and the impact of different intraocular lens (IOL) models on PCO characteristics using optical coherence tomography (OCT).

METHODS

Eighty-three eyes with PCO (fibrosis or pearl type) and 32 pseudophakic eyes without PCO were included. Horizontal 3.0 mm long OCT scans of the posterior capsule were obtained. Measurements and means of the peak posterior capsule intensity (PCI) and posterior capsule thickness (PCT) (distance between 2 spikes at posterior capsule) at 3 scan points were recorded. The PCI and PCT were compared with best corrected visual acuity (BCVA) and IOL data.

RESULTS

The PCT was high for IOLs with a rounded edge (P = .001) and with poly(methyl methacrylate) (PMMA) IOLs (P<.001). If the IOL optic was concave-convex, the PCT was higher than if the optic was biconvex (P = .001). The PCT of hydrophilic acrylic IOLs was higher than of hydrophobic acrylic IOLs (P = .04). Multivariate analysis of PCT showed that PMMA was the only factor statistically associated with PCT (P = .02). The worse logMAR BCVA correlated significantly with a higher PCT value (P<.001) but not with PCI (P = .42). An IOL size of 12.5 mm was related to fibrosis-type PCO (odds ratio, 3.14; P = .04).

CONCLUSIONS

The PCT was most affected by IOL characteristics. Poly(methyl methacrylate) IOLs and IOLs with rounded edges were associated with higher PCT. Hydrophilic acrylic IOLs were associated with greater PCT than hydrophobic IOLs. Posterior capsule thickness was a factor in decreased BCVA.

Evaluation of lens epithelial cell migration in vivo at the haptic-optic junction of a one-piece hydrophobic acrylic intraocular lens

PURPOSE

To evaluate the pattern of lens epithelial cell (LEC) ingrowth behind the intraocular lens (IOL) optic in patients implanted with the AcrySof SA60AT one-piece IOL.

DESIGN

Retrospective case series.

METHODS

Patients implanted with the AcrySof SA60AT one-piece IOL with complete overlap of the capsulorrhexis and IOL optic and no ocular pathology were selected from the practices of six surgeons. High-resolution digital images of the distribution of LECs were captured. Circumferential location and extent of LEC growth behind the optic were measured.

RESULTS

Mean +/- SD follow-up was 13.2 +/- 1.7 months for 40 patients (mean age 72 years). LEC migration beyond the edge of the IOL optic was displayed by 57.5% (23/40) of patients. LECs migrated into the visual axis in 22.5% (9/40) of patients, leading to a visual acuity of <6/9 (20/30) in 10% (4/40) of patients. Cell migration was located preferentially at the optic-haptic junction. Serial photographs were used to monitor LEC migration over time. In some cases, LECs extended from the opposing optic-haptic junctions to converge in the center of the IOL, creating a path across the optic.

CONCLUSIONS

The optic-haptic junction of the AcrySof one-piece IOL is a point of weakness in the barrier effect of the square-edge IOL design that provides migrating LECs access to the posterior capsule.

Intraocular lens decentration and posterior capsule opacification: anatomo-pathologic findings after implantation of AMOSI40 IOLS

PURPOSE

To evaluate the incidence of intraocular lens (IOL) decentration and posterior capsule opacification (PCO) after implantation of a three-piece posterior chamber silicone IOL in a series of eyes examined postmortem.

METHODS

Twenty-three pseudophakic enucleated human cadaver eyes, implanted with AMO SI40NB IOLs after phacoemulsification, were analyzed. Eyes obtained postmortem were sectioned at the equatorial plane and the anterior segment photographed from a posterior view. Location of IOL optic and haptics, type of fixation, and centration of IOL was evaluated. PCO was graded and the presence of Nd:YAG laser posterior capsulotomy was noted.

RESULTS

Mean age at the time of surgery was 77.83 years, mean time since implantation was 18.26 months. In all the eyes examined, IOL haptics were positioned in the capsular bag. Mean decentration was 0.20+/-0.16 mm. No correlation was found between IOL decentration and time since implantation. The degree of peripheral PCO ranged from none (13.0%) to mild (39.1%) to moderate (26.1%) to severe (21.7%). The degree of central PCO ranged from none (52.2%) to mild (30.4%) to moderate (4.3%). Three patients (13.0%) underwent Nd:YAG laser posterior capsulotomy.

CONCLUSIONS

A very good centration can be obtained when silicone AMOSI40NB IOLs are correctly implanted with the haptics inside the capsular bag. About half of the implants showed no central PCO while Nd:YAG laser posterior capsulotomy rates documented a relatively low PCO 18 months after surgery. A careful in the bag haptics placement is needed in order to reduce the IOL decentration and to prevent central PCO.

Effect of hydrodissection alone and hydrodissection combined with rotation on lens epithelial cells

PURPOSE

To evaluate the impact of corticocleaving hydrodissection alone and hydrodissection combined with rotation on lens epithelial cells (LECs) and residual cortical fibers (RCFs).

SETTING

Iladevi Cataract and IOL Research Center, Ahmedabad, India.

METHODS

An experimental laboratory study of 20 fresh human cadaver eyes (10 pairs) was conducted. A single eye from each pair was assigned to the control group, in which no hydrodissection and no rotation were performed (control). The other eye was randomized to corticocleaving hydrodissection alone (Group 1) or corticocleaving hydrodissection with rotation (Group 2). Cataract extraction was standardized. Capsule polishing was omitted. Area of LEC loss (%) in the preequatorial zone (PZ) and equatorial zone (EZ) was calculated as: [Area of capsule without cells/Total area of capsule] x 100. Area of presence of RCFs (%) was calculated as: [Circumference of EZ of capsule with RCF/Total circumference of EZ of the capsule] x 100. The Mann-Whitney U and the Wilcoxon signed rank tests were applied.

RESULTS

In the control group, area of cell loss (%) was 3.9 +/- 3.2 in the PZ and 2.7 +/- 0.8 in the EZ; presence of RCFs (%) was 83.8 +/- 1.7. Area of LEC loss (%) in Groups 1 and 2 was 24.8 +/- 4.5 and 42.6 +/- 5.4 (P = .008) in the PZ and 22.4 +/- 2.1 and 54 +/- 2.5 (P = .008) in the EZ, respectively. Area of presence of RCFs (%) in Groups 1 and 2 was 34.2 +/- 3.7 and 23.7 +/- 3.7 (P = .008), respectively.

CONCLUSION

Corticocleaving hydrodissection combined with rotation removed significant quantities of LECs and RCFs.

Evaluating and defining the sharpness of intraocular lenses

PURPOSE

To develop a new method for the evaluation of the optic edge design of intraocular lenses (IOLs).

SETTING

Charité Humboldt University and Berlin Eye Research Institute (Beri), Berlin, Germany.

METHODS

Poly(methyl methacrylate) IOLs with 11 edge designs were manufactured. Each lens design was evaluated using EPCO 2000. Also, edge's ability to stop cell growth was observed by placing each IOL into cell culture and observing cell growth over 18 days on average.

RESULTS

Only 3 groups, those with the sharpest edge design, prevented the growth of lens epithelial cells onto the visual axis of the lens. The edge design that effectively stopped cell growth was characterized by an area above the edge of 13.5 microm2 at the most.

CONCLUSION

Results shows that the edge design of IOLs plays an important role in the prevention of posterior capsule opacification. A specific optic edge design was most effective in this prevention.

[New methods for the prevention of posterior capsule opacification]

Even though tremendous advances have been made especially during the last 10-15 years in terms of surgical techniques and improvement of implant technology, posterior capsule opacification (PCO) still remains a serious long-term complication. New clinical and laboratory studies (especially of autopsy eyes) have improved our understanding of how IOL design and material influence PCO. Sharp edge optic designs of IOLs of various materials have been shown to significantly reduce secondary cataract. The application of pharmacological substances selectively into the capsular bag is now possible due to the development of the PerfectCapsule System for vacuum-sealed capsule irrigation. Major advances in other areas of biotechnology and immunology including gene therapeutic methods offer totally new approaches for the future in the elimination of lens epithelium cells from the capsular bag. This survey gives an update on current and future means and trends to reduce or prevent PCO formation.

Posterior vertical capsulotomy with optic entrapment of the intraocular lens in congenital cataracts--prevention of capsule opacification

PURPOSE

To present a modified surgical technique for preventing posterior capsule opacification (PCO) in children with congenital cataracts and to evaluate its long-term efficacy.

SETTING

Department of Ophthalmology, Medical University of Southern Africa, Medunsa, South Africa.

METHODS

Anterior and posterior vertical capsulotomy, with optic entrapment of the intraocular lens (IOL) by maintaining the anterior hyaloid, was performed in 68 cataractous eyes of children aged 2 months to 8 years (mean 3 years, 1 month). The posterior capsule was evaluated for at least 5 years for secondary opacification, IOL position, pigmentary deposits on the IOL optic, and the presence of synechias.

RESULTS

Sixty-eight eyes maintained a clear visual axis for 5 to 12 years (mean 9 years, 1 month) postoperatively. No secondary procedure was necessary. In all eyes, the IOL remained well centered and entrapped.

CONCLUSIONS

Posterior capsulotomy with optic entrapment of the IOL proved to be a safe and efficient surgical procedure for preventing PCO in children with congenital cataracts. Uniting the anterior and posterior capsule in front of the IOL limits the proliferation and migration of Elschnig pearls. An intact anterior hyaloid does not induce capsule opacification in association with optic entrapment; therefore, a vitrectomy is not indicated even in infants under age 5 years. Clear visual axis, centered IOL, and intact vitreous were achieved in this series; this enables a promising long-term prognosis for binocular visual development, especially because surgery was performed early.

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.

Incidence of and risk factors for residual posterior capsule opacification after cataract surgery

PURPOSE

To evaluate the incidence of and determine the risk factors for residual posterior capsule opacification (PCO).

SETTING

University of New Mexico Health Sciences Center and the Veterans Administration Medical Center, Albuquerque, New Mexico, USA.

METHODS

This study evaluated 194 uneventful cataract surgeries. Immature cataracts were graded for nuclear sclerosis (NS), posterior subcapsular cataract (PSC), and anterior cortical spokes on a 1 to 4 scale. Preoperative Snellen best corrected visual acuity was converted to the logMAR scale. The posterior capsule was examined after polishing and was classified as clear or as having residual opacity. Those with residual capsule opacity were evaluated 6 weeks postoperatively for the presence of visually significant PCO.

RESULTS

The incidence of residual capsule opacity was 23% (44 eyes). Seven (54%) of 13 eyes with white mature cataract had residual capsule opacity. In contrast, 37 (20%) of 181 eyes with immature cataract had residual capsule opacity (P = .01). In eyes with immature cataract, the mean preoperative logMAR acuity was +1.14 +/- 0.60 (SD) in the residual capsule opacity group and +0.73 +/- 0.46 in the clear group (P<.001). In eyes with immature cataract, the adjusted odds ratio for each increasing grade of NS was 2.3 and of PSC, 1.8 (P = .002 and P<.001, respectively). Eleven percent (5 eyes) of residual capsule opacities resulted in visually significant PCO 6 weeks postoperatively. All 5 opacities were centrally located at surgery.

CONCLUSIONS

Results indicate that aggressive polishing of peripheral or adherent residual capsule opacities is not advisable as only 5 eyes with central residual capsule opacities developed visually significant PCO.

Comparison of posterior capsule opacification between the 1-piece and 3-piece Acrysof intraocular lenses: two-year results of a randomized trial

PURPOSE

To compare intensity of posterior capsule opacification (PCO) between the 1-piece and 3-piece haptic designs of an open-loop hydrophobic acrylic intraocular lens (IOL).

DESIGN

A randomized, patient- and examiner-masked clinical trial with intraindividual comparison.

PARTICIPANTS

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

METHODS

Each patient had cataract surgery in both eyes and received a 1-piece Acrysof IOL in one eye and a 3-piece Acrysof IOL in the fellow eye. Follow-up examinations were at 1 week, 1 month, 6 months, 1 year, and 2 years. Patients were examined at the slit lamp, visual acuity (VA) was determined, and standardized high-resolution digital retroillumination images of the posterior capsule were taken. The intensity of PCO was assessed subjectively at the slit lamp and objectively using automated image analysis software.

MAIN OUTCOME MEASURE

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

RESULTS

There was no significant difference between IOL styles in best-corrected VA, rhexis/IOL overlap, capsular folds, and amount of anterior capsule opacification during the follow-up period. One year postoperatively, the amount of regeneratory PCO was higher for the 1-piece Acrysof eyes (image analysis software score: 1.3) than for the 3-piece Acrysof eyes (score: 0.9; P = 0.002). However, 2 years postoperatively, there was no significant difference between the 2 IOL styles (1-piece: 1.5; 3-piece: 1.3; P = 0.3). Neodymium:yttrium-aluminum-garnet capsulotomy was not performed in the study.

CONCLUSION

One year postoperatively, the 1-piece Acrysof showed slightly more regeneratory PCO than the 3-piece Acrysof. However, 2 years postoperatively, the barrier effect of the 1-piece design was comparable to that of the 3-piece haptic design, with low PCO intensity.

Position of anterior capsulorhexis and posterior capsule opacification

PURPOSE

To evaluate whether the position of the anterior continuous curvilinear capsulorhexis influences the rate of posterior capsule opacification (PCO).

METHODS

A total of 119 patients, aged 61-86 years, underwent cataract surgery with phacoemulsification performed by a single surgeon. The patients were randomized to implantation with either a silicone intraocular lens (IOL) (SI40NB, Allergan) or an AcrySof IOL (MA60BM, Alcon). Three years after surgery, the rate of PCO was analysed using the evaluation of posterior capsule opacification computer software (EPCO). The results were related to the capsulorhexis position, which was assessed with a retroillumination photograph.

RESULTS

If the capsulorhexis was located partially or completely off the optics of the IOL, compared to totally on the IOL, significantly more PCO was found (p = 0.0014). When comparing within each IOL type, patients with AcrySof IOLs were found to have significantly less PCO when the capsulorhexis was totally on the optic (p = 0.0048). This difference was also significant in the silicone group (p = 0.041).

CONCLUSION

A relatively small and central capsulorhexis allowing for the complete covering of the IOL optics by the rhexis edges seems to protect against PCO in cataract surgery, with both round-edged silicone IOLs and sharp-edged hydrophobic acrylic IOLs.

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.

Pathological evaluation of postmortem human eyes implanted with a new single-piece hydrophobic acrylic lens

PURPOSE

To report the pathological findings in 14 human cadaver eyes implanted with a single-piece AcrySof(Alcon Laboratories) posterior chamber intraocular lens (IOL).

SETTING

David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

METHODS

Fourteen human autopsy eyes implanted with a single-piece AcrySof (SA30AL) IOL were evaluated. The eyes were sectioned at the equatorial plane, and the anterior segment containing the IOL in the capsular bag was evaluated from a posterior perspective (Miyake-Apple view) and from an anterior perspective (surgeon's view) after removal of cornea and iris. They were then processed through paraffin, sectioned, and stained with hematoxylin-eosin, periodic acid-Schiff, and Masson's trichrome and examined under light microscopy.

RESULTS

All IOLs had symmetric in-the-bag fixation. Slight decentration was measured in 1 eye, which also had an anterior capsule tear. Grade 1 anterior capsule opacification was present in 9 eyes. No central posterior capsule opacification or posterior capsule folds were observed in any eye. Soemmering's ring formation was observed in 5 eyes. Zonular stretch caused by different degrees of capsular bag contraction was present in 4 eyes without decentration of the IOL.

CONCLUSIONS

Analyses of pseudophakic cadaver eyes from the posterior (Miyake-Apple) view, complemented by microscopic analyses, proved useful in the evaluation of IOL-capsular bag interaction. These studies are more important in cases of newly introduced lens designs.

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.

Single-piece hydrophobic acrylic intraocular lens explanted within the capsular bag

A 74-year-old woman had uneventful phacoemulsification with implantation of a single-piece hydrophobic acrylic intraocular lens (IOL) (SA30AL) in her left eye. Two weeks after the surgery, the patient presented for ophthalmological consultation reporting pseudophakic dysphotopsia, which she had subjectively noted since surgery. Explantation/exchange of the IOL was performed 3 months after the surgery. The IOL was strongly attached to the capsule, which was fibrotic and contracted; explantation of the capsular bag complex in toto was done. To our knowledge, this is the first case of explantation of this IOL design with clinicopathological correlation.

Primary IOL implantation in children: a risk analysis of foldable acrylic v PMMA lenses

BACKGROUND

/aims: To compare the relative risks of poly (methylmethacrylate) (PMMA) and soft acrylic (AcrySof) primary intraocular lens (IOL) implantation in paediatric cataract surgery.

METHODS

A retrospective analysis of clinical data was performed on eyes of 61 infants and children who underwent cataract surgery with primary IOL implantation. Age at operation ranged from 3 weeks to 15 years. Mean follow up duration was 24.5 months (range 0.5-68 months). Factors examined included type of IOL (PMMA, acrylic), performance of a primary posterior continuous curvilinear capsulorhexis (PCCC) or capsulotomy with limited anterior vitrectomy, perioperative complications, and subsequent intervention for posterior capsule opacification (PCO). Risk factors for perioperative complications were examined with 2x2 tables to give odds ratios (OR) as measures of association. A survival analysis was performed to assess risk of subsequent intervention for PCO with different IOL types. Relative risks (hazards) and confidence intervals (CI) were calculated with Cox regression to adjust for potential confounding.

RESULTS

Compared to acrylic, PMMA IOLs were significantly associated with perioperative complications (OR 5.2, 95% CI 1.4 to 19, p = 0.01). However, IOL and type of section were highly correlated factors, and this finding may reflect risks associated with larger scleral wounds used for PMMA IOLs. No statistically significant difference in risk of subsequent intervention for PCO was found between different IOL types. Mean times till intervention for PMMA and acrylic IOLs were 30.1 months (95% CI 22 to 38) and 19.8 months (95% CI 12 to 27) respectively (log rank test statistic 1.53, one degree of freedom, p = 0.22). At 12 months post-implant surgery, 76% (95% CI 59 to 93) of PMMA cases and 54% (95% CI 35 to 72) of acrylic cases had not required intervention for PCO; these proportions fell to 55% (95% CI 35 to 75) and 38% (95% CI 14 to 61) for PMMA and acrylic cases respectively at 2 years post-surgery. After adjustment for age at surgery, primary posterior capsulorhexis, and perioperative complications relative risk of intervention after acrylic IOL implantation was 1.6 (95% CI 0.66 to 3.9, p = 0.29).

CONCLUSION

Primary implantation of foldable soft acrylic IOLs in paediatric eyes may allow fewer perioperative complications than rigid PMMA IOLs. Short term safety profiles of primary implantation in paediatric cataract surgery are otherwise comparable for PMMA and soft acrylic IOLs.

Long-term observation of the refraction with a reversed-optic posterior chamber intraocular lens

A 73-year-old man had phacoemulsification and implantation of a posterior chamber intraocular lens (PC IOL) in both eyes. In the right eye, the optic was unintentionally reversed in the bag. In the left eye, the posterior capsule was ruptured and the IOL haptics were fixated in the ciliary sulcus. The refraction in the sulcus-fixated left eye was stable from 1 month to 4 years. The right eye had a myopic shift at 1 month, with a regression of 1.50 diopters that continued for 2 years. The final IOL position in the right eye was 0.25 mm anterior to the position predicted by the SRK/T formula. It took 2 years for the refraction in the eye with the reversed-optic PC IOL to become stable. A large myopic shift and gradual regression in refraction may stem from a different wound-healing reaction than that of properly fixated IOLs.

Deposition of silicone oil droplets in the residual anterior lens capsule after vitrectomy and lensectomy in rabbits

AIM

To examine the histology of preserved anterior lens capsule in vitrectomised and lensectomised rabbit eyes with and without silicone oil tamponade.

METHODS

Forty adult Japanese albino rabbits received two port vitrectomy and lensectomy with or without silicone oil tamponade in one eye under both general and topical anaesthesia. Anterior lens capsule was preserved during operation. After healing intervals residual anterior capsule was histologically observed under light or electron microscopy.

RESULTS

Immediately after operation, cuboidal lens epithelial cells were observed on the posterior surface of the preserved anterior capsule. During healing intervals in eyes with or without silicone oil tamponade, regenerated lens structure of Sommerring's ring and fibrous tissue formed in the peripheral and central areas of the residual capsule, respectively. Ultrastructural observation revealed the presence of many vacuoles amid matrix accumulation on the posterior capsular surface, suggesting the deposition of emulsified silicone oil droplets.

CONCLUSION

Lens epithelial cells produce regenerated lenticular structure and fibrous tissue on the residual capsule following vitrectomy and lensectomy in rabbits. Silicone oil droplets formed by its emulsification deposit in extracellular matrix accumulated on the posterior surface of the anterior capsule. Emulsified silicone may potentially enhance opacification of residual anterior capsule following pars plana vitrectomy by silicone oil deposition and subsequent activation of lens epithelial cells.

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.

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: 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.

Role of posterior capsulotomy with vitrectomy and intraocular lens design and material in reducing posterior capsule opacification after pediatric cataract surgery

PURPOSE

To study the effect of primary posterior capsulotomy with anterior vitrectomy (PPC + AV) and intraocular lens (IOL) design and material on the development of posterior capsule opacification (PCO) after pediatric cataract surgery.

SETTING

Tertiary care institution in India.

PATIENTS

Sixty-four eyes of 52 children ranging in age from 3 months to 12 years who had cataract extraction with IOL implantation were prospectively evaluated for a minimum postoperative period of 2 years.

METHODS

Thirty-two eyes received a hydrophobic acrylic lens with a truncated, square edge and 32, a single-piece poly(methyl methacrylate) (PMMA) lens that was not heparin surface modified. Sixteen eyes in each IOL group had PPC + AV; in the remaining 16 eyes in each group, the posterior capsule was left intact.

RESULTS

Postoperatively, 25 eyes in the intact capsule group and 5 in the PPC + AV group developed PCO; the difference between groups was significant (P<.05). Of eyes with an intact capsule, 12 with an acrylic IOL and 13 with a PMMA IOL developed PCO (P>.05). In the PPC + AV group, 2 eyes with an acrylic IOL and 3 with a PMMA IOL developed PCO (P>.05). Overall, 14 eyes with an acrylic lens and 16 eyes with a PMMA lens developed PCO (P>.05). After surgery, there was a significant short-term delay in the development of PCO in the acrylic group (14 eyes; mean 6.66 months +/- 1.57 [SD]) compared to the PMMA group (16 eyes; mean 3.16 +/- 0.83 months) (P<.05).

CONCLUSIONS

It is the management of the posterior capsule rather than IOL design and material that influences the incidence of PCO after cataract surgery in children. Development of PCO in the postoperative period was delayed with a hydrophobic acrylic IOL with square edges compared with a PMMA lens without square edges.

Posterior capsule opacification: comparison of 3 intraocular lenses of different materials and design

PURPOSE

To compare posterior capsule opacification (PCO) after cataract surgery with implantation of 3 intraocular lenses (IOLs) of different materials and design.

SETTING

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

METHODS

In this prospective clinical study, 180 patients had standardized phacoemulsification performed by a single surgeon and were randomized to have implantation of a heparin-surface-modified (HSM) poly(methyl methacrylate) (PMMA) IOL (809C, Pharmacia & Upjohn), a silicone IOL (SI-40NB, Allergan), or an acrylic IOL (AcrySof MA60BM, Alcon). To morphologically evaluate PCO, retroillumination photographs were obtained and analyzed using Evaluation of Posterior Capsule Opacification computer software. The neodymium:YAG (Nd:YAG) capsulotomy rate was recorded.

RESULTS

After 2 years, the HSM PMMA IOL group had significantly more PCO than the silicone and AcrySof IOL groups; the silicone group had significantly more PCO than the AcrySof group (P<.05). The Nd:YAG capsulotomy rate was 20% in the HSM PMMA group, 22% in the silicone group, and 8% in the AcrySof group.

CONCLUSION

Patients with an AcrySof IOL developed significantly less PCO than those with a silicone or HSM PMMA IOL with a round-edged design.

Single-action implantation of a 3-piece acrylic intraocular lens with an injector

We report a method to insert a 3-piece AcrySof MA30BA acrylic foldable intraocular lens (IOL) (Alcon) in a single action using a Monarch II (Alcon) injector. The technique was used in 134 eyes. The incision widths ranged from 3.00 to 3.75 mm. The IOLs were successfully inserted in the capsular bag. Complications included cracks in the IOL optic in 3 eyes (3%), haptic damage in 3 eyes (3%), and inadequate self-sealing of the incision in 18 eyes (13%).

Management of coincident cataract and uveitis

Cataract surgery in a patient with uveitis is more complex than senile cataract extraction, because it involves multiple considerations related to the cause of uveitis, prospects of visual rehabilitation, appropriate surgical timing and technique, and the type and material of the intraocular lens used. Establishing the diagnosis, thorough eye examination, careful patient selection and meticulous control of perioperative inflammation are key elements to a successful visual outcome. Our aims in this article are to review the literature on this subject over the past year and highlight the behavior of intraocular lenses of various biomaterials in the uveitic eye. In addition, we also reemphasize the idea of a model of zero tolerance to intraocular inflammation to minimize the incidence of irreversible damage to ocular structures essential to good vision.

Scanning electron microscopic and histologic evaluation of the AcrySof SA30AL acrylic intraocular lens. Manufacturing quality and morphology in the capsular bag

PURPOSE

To evaluate the properties of the AcrySof(R) SA30AL (Alcon Laboratories, Inc.) single-piece foldable posterior chamber intraocular lens (IOL).

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

Two nonimplanted clinical-quality AcrySof IOLs were examined by gross, light, and scanning electron microscopy (SEM). In addition, 2 eyes implanted with this IOL obtained post-mortem, the first such eyes accessioned in our laboratory and the first described to date, were examined using the Miyake-Apple posterior photographic technique and by histologic sections.

RESULTS

Scanning electron microscopy of the SA30AL IOL showed excellent surface finish. The edge of the optic was square (truncated) and had a matte (velvet or ground-glass) appearance, a feature that may minimize edge glare and other visual phenomena. A well-fabricated square or truncated optic edge was demonstrated. Miyake-Apple analysis revealed that the SA30AL IOL showed appropriate fit and configuration within the capsular bag. Histologic correlation of the IOL's square edge and its relation to the capsular bag and adjacent Soemmering's ring were noted.

CONCLUSIONS

The AcrySof SA30AL IOL is a well-fabricated lens that situates well in the capsular bag. The truncated optic and its relationship to adjacent structures show a morphological profile that has been shown to be highly efficacious in reducing the rate of posterior capsule opacification.

Phacoemulsification in patients with Fuchs' heterochromic uveitis

PURPOSE

To evaluate the results of phacoemulsification with capsular bag fixation of a poly(methyl methacrylate) (PMMA), acrylic, or silicone intraocular lens (IOL) in patients with complicated cataract resulting from Fuchs' heterochromic uveitis (FHU).

SETTING

Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

METHODS

This study evaluated 20 eyes of 19 patients with FHU and cataract who had uneventful phacoemulsification with endocapsular implantation of an IOL and completed a 1-year follow-up.

RESULTS

Preoperatively, loss of the iris collarette and fine keratic precipitates were seen in all 20 eyes, iris heterochromia in 16, iris atrophy in 12, and iris nodules in 2. Fourteen eyes had mild or negligible preoperative anterior chamber inflammation. No eye had increased intraocular pressure. An acrylic IOL was implanted in 10 eyes, a silicone IOL in 4, and a PMMA IOL in 6. There were no significant differences in outcomes among the 3 IOL groups. Three patients had intraoperative hyphema that resolved spontaneously. Postoperatively, 16 eyes had mild anterior chamber reaction. Four patients had significant anterior chamber inflammation necessitating the use of frequent topical steroids. No case had secondary glaucoma or posterior synechias. The best corrected visual acuity was 6/5 in 6 eyes, 6/6 in 11, and 6/9 in 3.

CONCLUSIONS

Uneventful phacoemulsification with endocapsular IOL implantation visually rehabilitated patients with FHU. All 3 IOLs yielded similar results except for increased early postoperative inflammation and late dense anterior capsule opacification in the silicone group. Further studies comparing the outcome of different IOL materials are required to determine their effectiveness in patients with FHU.

Evaluation of 3 modern single-piece foldable intraocular lenses: clinicopathological study of posterior capsule opacification in a rabbit model

PURPOSE

To assess the development of posterior capsule opacification (PCO) with 3 modern single-piece foldable intraocular lenses (IOLs) in a histopathological study and to compare the potential preventive effects of the IOL design and biomaterial in retarding PCO.

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

Thirty-one rabbit eyes were randomly operated on with phacoemulsification and implantation of 3 single-piece foldable lenses: a hydrophilic acrylic design, the Rayner Centerflex 570H (n = 11); a hydrophobic acrylic design, the Alcon AcrySof SA30AL (n = 10); and a silicone large-hole plate design, the Staar AA-4203VF (n = 10). Central PCO (CPCO), peripheral PCO (PPCO), and Soemmering's ring formation were evaluated 3 weeks after surgery using the Miyake-Apple posterior photographic technique. Histological sections of each globe were prepared to document capsular bag status and performance of IOL geometry.

RESULTS

The acrylic IOLs (Centerflex and AcrySof) had lower CPCO and PPCO scores than the silicone plate IOL (P <.05). There was no significant difference in Soemmering's ring formation among the 3 models. Pathological evaluations revealed effective blockage of migrating lens epithelial cells (LECs) at the site of the truncated optic edge of the Centerflex and AcrySof IOLs, even in the presence of large amounts of retained/regenerative cortical material.

CONCLUSIONS

The AcrySof IOL has a hydrophobic surface and the Centerflex a hydrophilic surface, but no correlation to these characteristics could be identified. The single-piece AcrySof optic geometry created a clear-cut barrier effect equal to that of its 3-piece predecessor. The anatomic profile of the Centerflex IOL shows the same characteristics. The optics of both acrylic lenses have square truncated edges that functionally block ingrowth of migrating LECs toward the central visual axis, leaving clear posterior capsules. The square optic edge was an appropriate geometric configuration to create a barrier effect. There was no effect of the biomaterial on PCO prevention.

Effect of haptic angulation on posterior capsule opacification in modern foldable lenses with a square, truncated optic edge

PURPOSE

To analyze the effect of different haptic angulations on posterior capsule opacification (PCO) in a modern foldable intraocular lens (IOL) with a square-edged optic designed to reduce the incidence of PCO.

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

Ten Dutch Belted, serum Pasteurella-free pigmented rabbits of the same age and sex had bilateral phacoemulsification with endocapsular IOL implantation. The eyes were implanted with Centerflex IOLs (Rayner) with haptic angulations of 0 degree (n = 8), 5 degrees (n = 4), 10 degrees (n = 4), or 15 degrees (n = 4).

RESULTS

There was no statistical difference in central PCO, peripheral PCO, and measured IOL decentration among the angulation groups.

CONCLUSION

With the Centerflex IOL, haptic angulation did not seem to be a significant factor influencing PCO. It appears that the barrier effect of the IOL's truncated, square-edged optic overrides the angulation factor in preventing PCO.

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.

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.

Results of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses in uveitic eyes with cataract: comparison to a control group

PURPOSE

To evaluate the uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses (IOLs) in eyes with uveitis.

SETTING

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

METHODS

This prospective study comprised 72 eyes with uveitis and 68 control eyes having phacoemulsification and IOL implantation by 1 surgeon. Patients received 1 of the following IOLs: foldable hydrophilic acrylic (Hydroview, Bausch & Lomb), hydrophobic acrylic (AcrySof, Alcon), or silicone (CeeOn 911, Pharmacia). Postoperative evaluations were at 1, 3, and 7 days and 1, 3, and 6 months. Cell reaction was evaluated by specular microscopy of the anterior IOL surface and the anterior and posterior capsule reaction, by biomicroscopy.

RESULTS

Small round cell deposition was observed on all IOLs in the immediate postoperative period, especially in eyes with uveitis. This reaction decreased 3 to 6 months after surgery. Although the CeeOn 911 had a higher mean grade of small cells, there was no statistical difference between the 3 IOL types after 6 months in the uveitis and control groups. Foreign-body giant cells (FBGCs) increased after 1 week to 1 month. The AcrySof IOLs had the highest number of FBGCs; after 6 months, there was a statistically significant difference between the AcrySof and Hydroview uveitis groups (P =.036) and the AcrySof and CeeOn 911 uveitis groups (P =.003) but there was no difference among the 3 IOL types in the control group. Lens epithelial cell outgrowth persisted on the Hydroview IOLs in control eyes and regressed on all 3 IOL types in uveitic eyes and on the AcrySof and CeeOn 911 IOLs in control eyes (P =.0001). Anterior capsule opacification (ACO) was more severe on all IOL types in uveitic eyes and on the CeeOn 911 IOL in control eyes. Posterior capsule opacification (PCO) was more severe in uveitic eyes. The Hydroview group had more severe PCO than the AcrySof and the CeeOn 911 groups in uveitis and control eyes. Six months postoperatively, the difference was significant (P =.0001). There was no significant difference between the AcrySof and CeeOn 911 IOLs.

CONCLUSIONS

Intraocular lens biocompatibility is inversely related to inflammation. Hydrophilic acrylic material had good uveal but worse capsular biocompatibility. Hydrophobic acrylic material had lower uveal but better capsular biocompatibility. Silicone showed a higher small cell count (mild) and more severe ACO but achieved PCO results comparable to FBGC results and better than those with the AcrySof lens 6 months after surgery. Despite the differences in IOL biocompatibility, all patients benefited from the surgery.