Comparison of the biomechanical behavior of foldable intraocular lenses

PURPOSE: To compare a standardized battery of biomechanical laboratory tests to assess the performance of popular foldable intraocular lenses (IOLs). SETTING: Biomedical testing facilities, Alcon Research, Ltd., Fort Worth, Texas, USA. METHODS: Using industry-standard biomechanical testing techniques, 1- and 3-piece foldable IOLs (Alcon AcrySof MA60BM, MA30BA, SA30AL, SA60AT; Allergan Sensar AR40, PhacoFlex II SI-40NB; Bausch & Lomb Soflex LI61U; Pharmacia & Upjohn CeeOn 920) and a 1-piece all-poly(methyl methacrylate) (PMMA) IOL (Alcon MZ30BD) were tested under identical conditions with regard to (1) tensile/elastic properties by comparing haptic pull strength and haptic elongation and (2) compression properties by comparing haptic compression forces, haptic compression force decay over time, and axial displacement. All tests were performed with the IOLs submersed in a controlled-temperature water bath (mean 35 degrees C +/- 2 degrees C [SD]). RESULTS: For all IOLs, the ultimate elongation and pull strength of the haptics before failure was highest with the Alcon SA30AL and SA60AT. Similarly, the force required to compress haptics to a prescribed 10.0 mm diameter was least with the SA30AL and the SA60AT lenses. These 1-piece lenses also showed the least decay of residual compression force as a function of time. Optic displacement along the optical axis with haptic compression to 10.0 mm was least with the Alcon 1-piece IOLs and the all-PMMA control IOL. CONCLUSION: AcrySof 1-piece SA30AL and SA60AT IOLs demonstrated superior biomechanical characteristics over other foldable IOL designs.     

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%).     

Posterior capsule opacification after implantation of CeeOn Edge 911A, PhacoFlex SI-40NB, and AcrySof MA60BM lenses: one-year results of an intraindividual comparison multicenter study

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.     

Glistenings in foldable intraocular lenses

PURPOSE: To evaluate the formation of glistenings in foldable intraocular lenses (IOLs) of various materials after cataract surgery. SETTING: University Eye Clinic of Trieste, Trieste, Italy. METHODS: In this prospective study, 273 patients were randomized to have implantation of 1 of 7 types of foldable IOLs in the capsular bag after phacoemulsification. The IOLs were the CeeOn Edge 911A (Pharmacia & Upjohn Co.), ACR6D (Corneal), AcrySof (Alcon), SI-40NB (AMO), Hydroview H60M (Storz), Sensar (AMO), and Stabibag (Ioltech). The presence of glistenings in the IOL optic was assessed by slitlamp evaluation 7, 30, 90, 180, 360, and 720 days after surgery. The glistenings were graded at each control. RESULTS: Glistenings were observed in all IOL groups. The percentage of patients with glistenings ranged from 40.0% to 67.5%, with the percentage increasing up to 90 days after surgery and then becoming stable in most groups. The AcrySof group had a continuous increase over time. The mean grade of glistenings increased up to 180 days after surgery and then became stable in most groups. The AcrySof and 911A groups had a continuous increase over time. CONCLUSIONS: Glistening formation was observed in 7 different foldable IOLs. The AcrySof group had a higher percentage and a greater density of glistenings.     

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

PURPOSE: To compare the posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) laser posterior capsulotomy rates associated with three different posterior chamber foldable intraocular lenses (IOL). METHODS: We retrospectively evaluated the rates of PCO and Nd:YAG laser capsulotomy in 1150 eyes two years after standard phacoemulsification with a no-stitch 3.5mm clear corneal incision (CCI) and in-the-bag implantation of one of three types of IOL: 190 eyes received a one-piece round-edged hydrogel IOL (Hydroview H60M, Bausch & Lomb); 475 eyes a three-piece round-edged silicone IOL (AMO PhacoFlex SI-40NB, Allergan); 485 eyes a three-piece square-edged soft acrylic lens (AcrySof MA60MA, Alcon). RESULTS: The PCO and Nd:YAG laser capsulotomy rates were respectively 43.15% and 20.5% in the Hydroview H60M group, 27.57% and 9.68% in the AMO PhacoFlex SI-40NB group, 10.5% and 2.47% in the AcrySof MA60MA group. CONCLUSIONS: PCO and Nd:YAG laser capsulotomy rates were significantly higher in the Hydroview H60M group and significantly lower with the AcrySof MA60MA lenses, which combine a bioactive constitutive material with the square-edged optic design.     

Wound complications associated with incision enlargement for foldable intraocular lens implantation during cataract surgery

PURPOSE: To ascertain whether enlarging the incision for implantation of MA60 intraocular lenses (IOLs) causes increased wound instability and compare the incidence of wound-related complications with that after SI-40NB IOL implantation through an unenlarged incision. METHODS: This retrospective study comprised operative and postoperative notes of consecutive patients who had implantation of an Allergan SI-40NB IOL using the Unfolder or an Alcon MA60 AcrySof IOL from April 30, 1999, and before. The operative reports were used to determine whether there were any wound problems, particularly the need to suture the wound. Records from the first postoperative day were reviewed for evidence of wound leak or other wound-related complications. RESULTS: Of the 200 eyes receiving an SI-40NB IOL, 3 (1.5%) required the placement of a suture during surgery to secure the wound. None had a wound leak 1 day postoperatively. Of the 200 eyes receiving an MA60 IOL, 12 (6.0%) required the placement of a suture during surgery to secure the wound. One eye had a wound leak 1 day postoperatively. The difference in the number of wound-related complications between the 2 IOL groups was significant (P =.01). CONCLUSIONS: Significantly more wound-related complications occurred after incision enlargement for implantation of MA60 IOLs than after implantation of SI-40NB IOLs through unenlarged incisions.     

Uveal and capsular biocompatibility after implantation of sharp-edged hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses in eyes with pseudoexfoliation syndrome

PURPOSE: To evaluate the uveal and capsular biocompatibility of 3 types of sharp-edged foldable intraocular lenses (IOLs) in eyes with pseudoexfoliation syndrome (PEX). SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: Eighty-five eyes with PEX had implantation of 1 of the following sharp-edged 3-piece IOLs: hydrophilic acrylic (Injectacryl F3000, OphthalMed), hydrophobic acrylic (AcrySof MA60MB, Alcon), or silicone (CeeOn 911, AMO). Postoperative evaluation (flare, cellular reaction, and capsular reaction) was performed at 1, 3, and 7 days as well as 1, 3, 6, and 12 to 18 months. RESULTS: One year after surgery, flare was comparable between the IOLs. In terms of uveal biocompatibility, whereas the Injectacryl had the highest deposition of debris on the IOL surface (P = .04), the CeeOn 911 had significantly more small round cells in the first 6 months (P<.03). The AcrySof had the highest number of foreign-body giant cells (P = .01). In terms of capsular biocompatibility, lens epithelial cell outgrowth was highest in the AcrySof group (P<.02). Anterior capsule opacification was comparable between the 3 groups. Posterior capsule opacification was mild in all groups but was significantly greater in the Injectacryl group (P<.05). There were no cases of clinically significant IOL decentration or capsule contraction. CONCLUSIONS: In general, inflammatory cells accumulated more easily on hydrophobic IOLs than on hydrophilic IOLs; the AcrySof IOL had the highest prevalence of foreign-body giant cells. All 3 IOLs had good biocompatibility, although the AcrySof group had increased inflammatory signs.     

Final clear corneal incision size for AcrySof intraocular lenses.

PURPOSE: To evaluate clear corneal incision size variation in phacoemulsification surgery after the implantation of 2 models of AcrySof intraocular lenses (IOLs). SETTING: Departamento de Oftalmología, Clínica Universitaria de Navarra, Universidad de Navarra, Pamplona, Spain. METHODS: This prospective study comprised 108 eyes that had phacoemulsification and implantation of an Acrysof IOL model MA60BM (56 eyes) or MA30BA (52 eyes). Wound incision size was quantified using the Nordan incision size measurer. The incision size for each IOL model was evaluated before and after implantation and its relationship with the complications during implantation analyzed. RESULTS: Mean incision size varied from 3.7 mm +/- 0.14 (SD) before implantation to 3.9 +/- 0.11 mm after implantation for the MA60BM model (P = .001) and from 3.3 +/- 0.15 mm to 3.4 +/- 0.13 mm for the MA30BA model (P = .001). Intraoperative complications occurred in 14 eyes, and difficulty during IOL implantation, in 23 eyes. There was no association between final incision size and complications. CONCLUSIONS: Incision size increased after the implantation of the 2 AcrySof IOL models used in this study. Modifications to model MA30BA have led to an average decrease in wound size of 0.5 mm with respect to the MA60BM model. Most difficulties encountered were attributable to improper IOL unfolding.     

Patient satisfaction after uneventful cataract surgery with implantation of a silicone or acrylic foldable intraocular lens. Comparative study.

PURPOSE: To compare patient satisfaction with vision 12 months after implantation of a silicone or acrylic foldable intraocular lens (IOL). SETTING: John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA. METHODS: Selection criteria included patients who had uneventful cataract extraction by phacoemulsification with a temporal clear corneal incision or superior scleral tunnel incision, a curvilinear capsulorhexis, and in-the-bag IOL placement. One hundred sixty-two patients surveyed had a mean follow-up of approximately 15 months (range 12 to 18 months). Patients were divided into 3 groups of 54 each based on IOL type: AMO SI-30/40, Alcon MA30BA, and Alcon MA60BA. All patients were surveyed over the telephone using a standardized questionnaire protocol. They were questioned about their perception of vision with best optical correction in relation to visual blurring symptoms, glare symptoms, night vision, near vision, and overall vision. RESULTS: There were no significant differences in patient satisfaction among the 3 IOL groups in visual blurring or night vision. Patients in the SI-30/40 and MA60BA groups reported significantly higher satisfaction with glare symptoms, near vision, and overall satisfaction than patients in the MA30BA group. CONCLUSION: The SI-30/SI-40 and the MA60BA IOLs received significantly higher patient satisfaction scores than the MA30BA IOL in glare symptoms, near vision, and overall satisfaction.     

Uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses.

PURPOSE: To evaluate the long-term response of 6 types of 3-piece intraocular lenses (IOLs) by assessing the cellular reaction on the anterior IOL surface, the behavior of posterior and anterior capsule fibrosis, and flare. SETTING: Department of Ophthalmology, Medical School, University of Vienna, Vienna, Austria. METHODS: One hundred eighty eyes were prospectively randomized to receive 1 of 6 IOLs: hydrophilic acrylic Hydroview (Bausch & Lomb) or MemoryLens (ORC); hydrophobic acrylic AcrySof MA60BM (Alcon) or AMO Sensar AR40 (Allergan); hydrophobic silicone CeeOn 920 or CeeOn 911A (Pharmacia). The patients had standardized cataract surgery, postoperative medication, and follow-up. One year after surgery, 155 eyes were assessed. The cellular reaction was evaluated by specular microscopy of the anterior IOL surface. Anterior and posterior capsule opacification (PCO) was assessed semiquantitatively by biomicroscopy. Flare was measured with a Kowa FC-1000 laser flare-cell meter. RESULTS: Regarding uveal biocompatibility, the hydrophobic acrylic IOLs showed the highest incidence of late foreign-body cell reaction (AcrySof, 30%; AR40, 17%) followed by the hydrophilic acrylic (MemoryLens, 8%; Hydroview, 4%) and silicone (CeeOn 920, 4%; CeeOn 911A, 0%) (P =.0044). In all cases, the cellular reaction was low grade and clinically insignificant. Regarding capsular biocompatibility, some eyes developed lens epithelial cell (LEC) outgrowth on the anterior IOL surface. The highest incidence was in the hydrophilic acrylic group (Hydroview, 85%; MemoryLens, 27%) followed by the hydrophobic acrylic (AcrySof, 4%; AR40, 3%). No silicone IOL had LECs on the anterior surface. The difference among IOL groups was significant (P =.0001). Anterior capsule opacification was more predominant in the hydrophobic IOL groups. Posterior capsule opacification of the central 3.0 mm area was lowest in the groups with a sharp-edged optic (CeeOn 911A, AcrySof) followed by the round-edged silicone (CeeOn 920), hydrophobic acrylic (AR40), and hydrophilic acrylic IOLs (P =.0001). There was a significant difference in flare between the AR40 lens and the Hydroview, MemoryLens, CeeOn 911A, and CeeOn 920 (P <.004). There was no statistically significant difference in the postoperative cell count at 1 year. The power calculation showed that the sample size was sufficient. CONCLUSIONS: The differences in cellular reaction, although clinically mild in normal eyes, indicate that there were more giant cells with hydrophobic acrylic IOLs and an increased tendency toward LEC outgrowth with hydrophilic lenses. The incidence of PCO was lowest in the hydrophobic IOL groups, especially in groups with a sharp-edged optic. Second-generation silicone IOLs with a sharp edge had good uveal and capsular biocompatibility 1 year after surgery.     

Posterior capsule opacification after phacoemulsification: foldable acrylic versus poly(methyl methacrylate) intraocular lenses

PURPOSE: To study the effects of foldable acrylic and poly(methyl methacrylate) (PMMA) intraocular lens (IOL) implantation on posterior capsule opacification (PCO). SETTING: Department of Ophthalmology, Dokuz Eylül University School of Medicine, Izmir, Turkey. METHODS: This consecutive series comprised 157 eyes having phacoemulsification with implantation of a foldable acrylic IOL with rectangular optic edges and a 5.5 mm optic (AcrySof) (n = 80 eyes) or a PMMA IOL with rounded optic edges and 5.5 mm optic (n = 77). Evaluated were incidence, location, and degree of PCO. Mean postoperative follow-up was 17.8 months +/- 1.7 (SD) (range 16 to 22 months). RESULTS: Posterior capsule opacification occurred in 8.7% of eyes in the foldable acrylic IOL group and in 24.7% of eyes in the PMMA IOL group. The difference between the 2 groups was statistically significant (P < .01). Centrally located PCO was significantly lower in the acrylic group (P < .01). There were 3 eyes with severe PCO in the PMMA group and none in the acrylic group. Anterior capsule contraction and fibrosis were present in 4 eyes in the PMMA group but none in the acrylic group. Soemmering's ring cataract formation was detected in 3 eyes, all with the AcrySof IOL. CONCLUSION: In addition to its optic material and rectangular optic edges, the AcrySof IOL provides additional advantages in lowering the incidence of PCO compared with rounded-edge PMMA IOLs.     

Incision width after phacoemulsification with foldable intraocular lens implantation

PURPOSE: To determine the incision size after insertion of foldable intraocular lenses (IOLs) using both a forceps and injectors. SETTING: Intermountain Ocular Research Center, Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: One hundred patients had phacoemulsification through a clear corneal wound. The incision width was measured before and after IOL implantation. A 3-piece silicone IOL and a 3-piece acrylic IOL (both with an optic diameter of 5.5 mm) were inserted using a forceps. A plate-haptic silicone lens and a 3-piece silicone lens with a 6.0 mm diameter optic were inserted using an injector. RESULTS: The wound size in the group with the 3-piece silicone lens inserted with a forceps enlarged 4.4% (3.23 to 3.38 mm) in the low-power IOL group (15.0 to 20.0 diopters [D]) and 6.2% (3.24 to 3.44 mm) in the high-power IOL group (20.5 to 25.0 D). Similarly, the acrylic IOL wound enlarged 5% (3.21 to 3.37 mm) in the low-power IOL group and 6% (3.25 to 3.44 mm) in the high-power IOL group when a forceps was used. The 3-piece silicone and plate silicone lenses inserted using an injector enlarged the wound 3.2% and 3.3% (3.02 to 3.11 mm and 3.05 to 3.15 mm), respectively. There was no difference in the wound size with higher IOL powers in eyes with injected lenses. CONCLUSIONS: Clear corneal incisions enlarge after insertion of foldable IOLs in a predictable manner, with a forceps-inserted IOL enlarging the wound diameter more than lenses inserted with an injector. The forceps-inserted lens group also showed a difference in wound size related to IOL power.     

Posterior capsule opacification and neodymium: YAG capsulotomy rates with AcrySof acrylic and PhacoFlex II silicone intraocular lenses

PURPOSE: To compare the incidence and severity of posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) capsulotomy rates between AcrySof(R) MA30BA acrylic (Alcon) and PhacoFlex(R) II SI-40NB silicone (AMO) intraocular lenses (IOLs). SETTING: Outpatient Cataract Surgery Center, TLC Eyecare and Laser Center, Jackson, Michigan, USA. METHODS: AcrySof and PhacoFlex II IOLs were implanted in fellow eyes of 156 patients requiring bilateral cataract extraction. The patients were followed for a mean of approximately 3 years for the incidence and severity of PCO and the Nd:YAG capsulotomy rates. RESULTS: Of the 63 eyes that were free of PCO throughout the study, 42 had the AcrySof IOL and 21 had the PhacoFlex II IOL. Of eyes that developed PCO, the mean severity in the AcrySof group was 16% less than that in the PhacoFlex II group. Of the 50 eyes that had an Nd:YAG capsulotomy, 17 were in the AcrySof group and 33 were in the PhacoFlex II group. All differences between groups were statistically significant (P<.05). CONCLUSION: The AcrySof MA30BA IOL was associated with less PCO proliferation and thus fewer Nd:YAG laser posterior capsulotomies than the PhacoFlex II SI-40NB IOL.     

Scheimpflug measurement of intraocular lens position after piggyback implantation of foldable intraocular lenses in eyes with high hyperopia

PURPOSE: To investigate the position of 3-piece foldable intraocular lenses (IOLs) after piggyback implantation for high hyperopia. SETTING: University Eye Hospital, Johann Wolfgang Goethe University, Frankfurt am Main, Germany. METHODS: Eight eyes of 5 highly hyperopic patients had phacoemulsification and implantation of 2 foldable IOLs. In 3 eyes, both IOLs were implanted in the capsular bag. In 5 eyes, 1 IOL was placed in the capsular bag and the second IOL in the ciliary sulcus. Intraocular lens optic tilt and decentration, combined thickness of both IOLs, and anterior chamber depth (ACD) were measured postoperatively over a period of 18 months using Scheimpflug photography. RESULTS: All eyes with both IOLs in the capsular bag showed interpseudophakic opacification, with a mean increase in combined IOL thickness of 0.4 mm, a decrease in ACD of 0.3 mm, and a corresponding hyperopic shift of 4.00 diopters. Eyes in which the anterior IOL was placed in the ciliary sulcus showed no changes in refraction or combined IOL thickness. In these eyes, the anterior IOL had a higher mean decentration (0.49 mm +/- 0.20 [SD] after 12 months) than the posterior IOL (0.21 +/- 0.13 mm after 12 months). CONCLUSIONS: Piggyback IOL implantation with placement of 2 foldable IOLs in the capsular bag can be followed by a hyperopic shift that may be caused in part by displacement of the IOLs. Placement of the anterior IOL in the ciliary sulcus can lead to higher decentration of this IOL.     

Sharp-edged intraocular lens design as a cause of permanent glare

PURPOSE: To evaluate patients who had implantation of an acrylic intraocular lens (IOL) and reported edge glare that did not lessen with time. SETTING: Hawthorn Eye Clinic, Kew, Victoria, Australia. METHOD: This retrospective study comprised patients who had uneventful phacoemulsification and then reported glare that did not abate after 12 months. RESULTS: Five patients (7 of 322 eyes; 2.2%) who received an AcrySof MA30BA IOL with a 5.5 mm optic and 1 patient (1 of 221 eyes; 0.5%) who received an AcrySof MA60BM IOL with a 6.0 mm optic reported permanent edge glare. Extensive retinal and neurological evaluations in 2 patients showed no deficits in 1 and an abnormal photopic red electroretinogram in the other. Pilocarpine 1% was used in 3 patients and gave no relief of symptoms. Two patients (3 eyes) had IOL explantation with complete resolution of glare symptoms. There was no statistical significance between the 2 types of IOLs. CONCLUSION: Sharp-edged IOL designs can cause permanent intractable glare.     

Negative dysphotopsia after intraocular lens implantation irrespective of design and material

We report 3 cases of negative dysphotopsia in patients who had implantation of 1 intraocular lens (IOL) type in 1 eye and another IOL type in the fellow eye. A male patient (aged 58 years) received an SA60AT AcrySof hydrophobic acrylic IOL (Alcon) in his left eye (OS). He noticed a temporal dark shadow. Three months later, he received a Tecnis Z9001 silicone aspheric optic IOL (Pfizer) in his right eye (OD). He noticed a temporal dark shadow OD almost identical to the shadow OS. Another male patient (aged 58 years) received an AcrySof MA60AC IOL (Alcon) OS and subsequently a PhacoFlex SI-40NB silicone IOL (AMO) OD. He experienced temporal dark shadows in each eye. A female patient (aged 64 years) received an SA60AT IOL OD and subsequently a Sensar hydrophobic acrylic AR40e (AMO) OS, noticing dark shadows in both eyes. Although all 3 patients tolerated the shadows well, they were interested in their etiology and wanted reassurance that the symptoms would not progress.     

Adhesion of soluble fibronectin,vitronectin, and collagen type IV to intraocular lens materials

PURPOSE: To evaluate soluble fibronectin, vitronectin, and collagen type IV adhesion to poly(methyl methacrylate) (PMMA), fluorine-surface-modified PMMA, silicone, hydrophobic and hydrophilic acrylate, and hydrogel intraocular lenses (IOLs) and determine whether hydrophobic and hydrophilic acrylate materials have different fibronectin-adhesion properties. SETTING: Department of Medical Biochemistry, University of Oulu, Oulu, Finland. METHODS: One hundred fifty IOLs were incubated for 1 week at 37 degrees C with radioactive-iodine-labeled soluble fibronectin, vitronectin, or collagen type IV. Fifty IOLs were analyzed for each protein, 5 from each of 10 different IOL models (PMMA, Alcon MC60BM; fluorine-surface-modified PMMA, Chiron Fluorilens Centra-55F; silicone, Allergan Medical Optics SI-40NB and Pharmacia and Upjohn CeeOn 911A; hydrophobic soft acrylate, Alcon AcrySof MA60BM and SA30AL and AMO Sensar; hydrophilic soft acrylate, Ioltech Stabibag and Bausch and Lomb BL27; and hydrogel, Bausch and Lomb Hydroview. The amount of adherent protein was measured with a gamma counter at 1 and 7 days and expressed as counts per minute. RESULTS: At 1 week, significantly more fibronectin was bound to the hydrophobic acrylate IOLs than to the 2-hydroxyethyl methacrylate (HEMA) containing hydrophilic acrylate IOLs (P <.05 to.0001). Significantly more vitronectin was bound to the 2 silicone IOLs than to any other IOL (P <.01 to.0001) at 7 days. Collagen type IV adhered best to the hydrophilic acrylate IOLs, which were significantly different (P <.01 to.0001) than the other IOLs at 1 and 7 days. CONCLUSIONS: Each IOL material had a different affinity to each protein. Significant binding to 1 protein does not indicate that the IOL will bind significantly to all proteins; instead, each protein should be studied separately. Fibronectin bound significantly better to hydrophobic acrylate IOLs than to hydrophilic acrylate IOLs, suggesting that the HEMA-containing IOLs should be classified with the hydrogel IOL group.     

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.     

Visual discomfort after acrylic intraocular lens implantation

A 64-year-old man had phacoemulsification in both eyes. In January 1998, an Allergan SI-30NB silicone intraocular lens (IOL) with a 6.0 mm optic was implanted in the right eye. In April, an Alcon AcrySof MA60BN acrylic IOL with a 6.0 mm optic was implanted in the left eye. The following October, the patient experienced visual discomfort in the left eye. Two superior radial minikeratotomies were performed. The patient continued to have visual discomfort and the next month, a topographic ablation was performed in the same eye. In January 2000, the left IOL was replaced with a 5.5 mm Allergan SI-55NB silicone IOL. Visual impairment resolved 1 day after surgery.     

Visual complaints associated with the AcrySof acrylic intraocular lens(1)

PURPOSE: To describe the visual complaints of a series of patients implanted with the AcrySof(R) (Alcon Surgical) acrylic intraocular lens (IOL) that resolved with IOL exchange. SETTING: Jules Stein Eye Institute, Los Angeles, California, and John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: This was a retrospective review of patients who had AcrySof IOL exchange from January 1997 to December 1998. RESULTS: Eight patients (9 eyes) with bothersome visual symptoms following AcrySof IOL implantation were identified. Problems included glare, halos around point light sources, and peripheral arcs of light, often worse at night. In each case, the IOL was well-centered in the capsular bag and there was no significant posterior capsule opacification. Six patients (7 eyes) had the MA30BA model with a 5.5 mm optic, and 2 patients (2 eyes) had the MA60BM model with a 6.0 mm optic. No extralenticular reasons for the patients' complaints could be identified. Exchanging the AcrySof IOLs with silicone or poly(methyl methacrylate) IOLs alleviated most symptoms. In 5 of 8 patients, dysphotopsias resolved completely. CONCLUSIONS: A small number of patients implanted with AcrySof IOLs have specific complaints of glare, halos, and peripheral arcs of light. Optical considerations that may help explain these symptoms include the high refractive index of the IOL material and the truncated design of the optic. Patients who are highly observant and those with large pupils may be particularly symptomatic. Intraocular lens exchange may be necessary in some cases.