不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

不同丙烯酸材料的人工晶状体对后发性白内障的影响

目的 探讨三种不同的丙烯酸材料的人工晶状体应用于白内障超声乳化吸除联合人工晶状体植入术后对后发性白内障的影响作用.方法 超声乳化白内障吸除联合人工晶状体植入术的960例白内障患者(964只眼),Sensar组310只眼,Acrysof三片组332只眼,Acrysof一片组322只眼,术后定期随访18～28个月,观察视力、后发性白障的发生情况.结果 术后随访24月时,发生1级以上后囊膜混浊SensarIOL组的发生率(13.5%),明显高于Acrysof一片式IOL组及Acrysof三片式IOL组的发生率(7.5%,3.7%).经卡方检验,P值均<0.05,有显著性差异,而Acrysof三片式IOL组后囊膜混浊的发生率较Aerysof 一片式IOL组高,P<0.05.结论 AcrySof丙烯酸式一片式人工晶状体植入后出现后发性白内障的发生率在三组中最低.可以减少后发性白内障的发生降低Nd:YAG激光的使用率,提高手术效果,是现代白内障手术可选择的理想的人工晶状体.     

Posterior capsule opacification and lens epithelial cell layer formation: Hydroview hydrogel versus AcrySof acrylic intraocular lenses

PURPOSE: To quantitatively compare the incidence of visually significant posterior capsule opacification (PCO) and lens epithelial cell (LEC) layer formation on the anterior surface of Hydroview hydrogel and AcrySof acrylic foldable intraocular lenses (IOLs) after implantation. SETTING: Single-surgeon ophthalmology practice, Orange Base Hospital, and Dudley Private Hospital, Orange, New South Wales, Australia. METHODS: This retrospective study comprised 166 eyes of 150 patients (after exclusions) who had cataract extraction and insertion of a foldable IOL in the capsular bag by a single surgeon using a standardized phacoemulsification technique from December 1997 to September 1998. The mean follow-up was 13.1 months (range 6.0 to 23.6 months). The eyes were divided into 2 groups based on the type of IOL implanted: Storz Hydroview H60M (81 eyes) or Alcon AcrySof MA30BA (85 eyes). A neodymium:YAG posterior capsule laser capsulotomy (PC YAG) was performed for an objective decrease in Snellen best corrected visual acuity (BCVA) of more than 1 line, significant visual symptoms, or both. This was used as a measure of visually significant PCO. An Nd:YAG anterior surface clearance (ASC YAG) was done for LEC layer formation anterior to the IOL to better visualize or facilitate treatment of PCO. The rates of PC YAG and ASC YAG after Hydroview and AcrySof IOL implantation were statistically compared. RESULTS: Forty-five eyes (55.6%) in the Hydroview IOL group and 3 eyes (3.5%) in the AcrySof IOL group required a PC YAG; the risk difference was 52.0% (P <.001). An ASC YAG was required in 27 eyes (33.3%) in the Hydroview group and 1 eye (1.2%) in the AcrySof group; the risk difference was 32.2% (P <.001). Survival analysis demonstrated that the only independent predictor of the incidence of PC YAG and ASC YAG over time was IOL type, with the Hydroview IOL group having a statistically significantly higher incidence of both procedures. CONCLUSION: There was a greater incidence of visually significant PCO and LEC layer formation on the anterior surface of Hydroview IOLs than of AcrySof IOLs.     

The effect of polymethylmethacrylate and acrysof intraocular lenses on the posterior capsule in patients with a large capsulorrhexis

PURPOSE: We have previously shown that patients who have a capsulorrhexis larger than the diameter of a polymethylmethacrylate (PMMA) intraocular lens (IOL) rapidly develop increased posterior capsule opacification (PCO), in effect, producing an example of enhanced PCO. This study focuses on the influence of AcrySof IOLs on this process. METHODS: Phacoemulsification was performed on two groups of patients. The first consisted of 38 patients with a large capsulorrhexis of 6-7 mm who received a 5.5-mm PMMA IOL. The second group of 32 patients had identical surgery and a 5.5-mm MA30 AcrySof IOL was implanted. On days 1,14, 28, 90, 180, and 360, high resolution digitized retroillumination images were taken of the posterior capsule. The PCO area was measured by image analysis at 90, 180, and 360 days. Wrinkling of the posterior capsule was determined at 90 days, and the progression or regression of lens epithelial cell (LEC) proliferation was established by examination of serial images at 28 and 180 days. RESULTS: At 90 days, 79% of the patients with PMMA IOLs had moderate to severe wrinkling of the posterior capsule, whereas the patients with AcrySof IOLs had none (P <.001). The percentage of PCO area was 69% for the PMMA IOLs and 24% for the AcrySof IOL group at 360 days (P <.0001). In the PMMA group, LEC progression occurred in 77%, LEC growth was stable in 15%, and LEC regression occurred in only 8%, compared to 69% of patients with AcrySof IOLs (P <.0001). CONCLUSIONS: In patients with a rhexis larger than the IOL, AcrySof IOLs potentially can prevent capsular wrinkling and cause less PCO than a PMMA IOL with a similar rhexis size. The LEC regression occurs with AcrySof between 28 and 180 days. The reasons for this are discussed.     

Posterior capsule opacification 3 years after implantation of an AcrySof and a MemoryLens in fellow eyes

PURPOSE: To compare the rates of lens epithelial cell (LEC) migration and posterior capsule opacification (PCO) 1 and 3 years after sutureless small incision phacoemulsification and in-the-bag implantation of 2 acrylic polymer intraocular lenses (IOLs)-the AcrySof and MemoryLens-in fellow eyes of patients. SETTING: Eye Clinic, Beyo?lu Education and Research Hospital, Istanbul, Turkey. METHODS: Fifty patients with no systemic or ocular problems that would interfere with postoperative visual acuity were included in this prospective study. Each patient had in-the-bag implantation of an AcrySof IOL in 1 eye and a MemoryLens in the fellow eye in a randomized fashion after uneventful phacoemulsification through a sutureless clear corneal incision. RESULTS: At 1 year (n = 32 patients), there was no significant difference between fellow eyes in postoperative best corrected visual acuity (BCVA) and contrast sensitivity. In the MemoryLens group, 10 eyes (31.3%) had PCO and 9 (28.1%), LEC migration. In the AcrySof group, no eye had PCO and 2 eyes (6.3%) had LEC migration (P <.001). At 3 years (n = 21 patients), 1 eye (4.7%) in the AcrySof group had PCO and 3 eyes (14.4%) had LEC migration without PCO. In the MemoryLens group, 1 eye (4.7%) had a clear posterior capsule, 11 eyes (52.4%) had LEC migration, and 9 eyes (42.9%) had PCO (P <.001). A neodymium:YAG capsulotomy was required in 4 eyes (19.0%) in the MemoryLens group but no eye in the AcrySof group. At 3 years, BCVA was lower in the MemoryLens group than in the AcrySof group (P <.05). CONCLUSION: The 3 year clinical data of fellow eyes indicate that the AcrySof IOL causes less PCO than the MemoryLens.     

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.     

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.     

Predicting posterior capsule opacification: value of early retroillumination imaging

PURPOSE: To investigate the value of early retroillumination imaging of the posterior capsule in predicting the eventual development of posterior capsule opacification (PCO). SETTING: Ophthalmology Department, St. Thomas' Hospital, and Department of Physics, King's College, London, United Kingdom. METHODS: All patients with retroillumination images of the posterior capsule taken 6 months and 2 years after uneventful phacoemulsification with in-the-bag intraocular lens (IOL) implantation were selected. The images were taken using the same hardware and analyzed with the same software to calculate the percentage area of the posterior capsule covered by lens epithelial cells. The percentage area of PCO with all IOL types 6 months postoperatively was correlated with that at 2 years. RESULTS: One hundred forty patients had analyzable images at 6 months and 2 years. Of these, 63 had a poly(methyl methacrylate) (PMMA) IOL (Pharmacia 812A or Storz P497UV), 33 an acrylic (Alcon AcrySof MA30 or SA30), 22 a silicone (Allergan SI-30), and 22 a hydrophilic acrylic (Bausch & Lomb Hydroview H60). The correlation of the percentage area of PCO at 6 months with that at 2 years resulted in an r value of 0.71 (P <.0001) in the entire group. The r value was 0.48 in the PMMA group and 0.86 in the foldable IOL group (P <.0001) (r value: AcrySof, 0.66; silicone, 0.82; Hydroview, 0.75). CONCLUSIONS: Retroillumination imaging of the posterior capsule 6 months after cataract surgery predicted the PCO outcome at 2 years in eyes with foldable IOLs.     

Relationship of AcrySof acrylic and PhacoFlex silicone intraocular lenses to visual acuity and posterior capsule opacification

PURPOSE: To compare the changes in visual acuity and the development of posterior capsule opacification (PCO) with AcrySof acrylic intraocular lenses (IOLs) (Alcon Laboratories) and second-generation PhacoFlex silicone IOLs (Allergan ). SETTING: Eye Associates of New Mexico and Southwest Colorado, Albuquerque, New Mexico, USA. METHODS: Medical charts of patients having cataract extraction with implantation of an AcrySof MA30BA or MA60BM (MA30/60) or PhacoFlex SI-30NB or SI-40NB (SI-30/40) IOL between January 1995 and June 1997 were abstracted. Analyzed were the changes in visual acuity and development of PCO 1 month postoperatively and at the last available ophthalmologist visit or the visit before neodymium:YAG (Nd:YAG) capsulotomy. RESULTS: Patients with MA30/60 acrylic IOLs were significantly older, had a worse preoperative best corrected visual acuity (BCVA), and had more concomitant ocular diseases than those with SI-30/40 silicone IOLs. The change in BCVA from preoperatively to 1 month postoperatively was equivalent in the 2 lens groups. The BCVA declined from 1 month postoperatively to the last recorded or pre-Nd:YAG visit. This decline was greater in eyes with SI-30/40 silicone IOLs than in those with MA30/60 acrylic IOLs. Although the decrease in BCVA between IOL types was not significantly different, eyes with a SI-30/40 silicone IOL were significantly more likely to develop PCO and have Nd:YAG capsulotomy. Eyes developing PCO had a statistically significant decline in BCVA from 1 month postoperatively to the last/pre-Nd:YAG visit. CONCLUSIONS: The MA30/60 acrylic lenses were associated with lower PCO and Nd:YAG capsulotomy rates than second-generation SI-30/40 silicone IOLs. Patients with MA30/60 IOLs also tended to have less of a decrease in visual acuity than patients with SI-30/40 silicone lenses, probably as a result of the difference in PCO rates between groups.     

Preventive effect of a second-generation silicone intraocular lens on posterior capsule opacification

PURPOSE: To compare the preventive effect of a second-generation silicone intraocular lens (IOL) on posterior capsule opacification (PCO) with that of a soft acrylic IOL. SETTING: Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan. METHODS: After phacoemulsification, a silicone IOL (PhacoFlex II) was implanted in 1 eye and an acrylic IOL (AcrySof) in the contralateral eye of 5 rabbits. RESULTS: The posterior view 3 weeks after surgery showed slightly more PCO in 3 eyes with the PhacoFlex II lens than in eyes with the AcrySof IOL, with the PCO obscuring the iris structures. In 2 eyes with an AcrySof IOL, slightly more PCO was seen. Histopathological examination revealed that a bend and complex folds in the posterior capsule were formed with both the PhacoFlex II and AcrySof IOLs. However, the capsular bend formed by the PhacoFlex II lens, which was caused by its blunt edge, was not as sharp as that with the AcrySof IOL and more PCO was seen in all eyes with a PhacoFlex II lens. CONCLUSIONS: Capsular bend formation does not necessarily require a sharp optic edge. A truncated optic rim of a certain thickness appears to form a bend. The capsule-bending does not appear to be an all-or-nothing effect. There seems to be a transition. That a capsular bend forms despite a blunt rather than a sharp optic edge may explain why the second-generation PhacoFlex II IOL prevents PCO better than first-generation and PMMA IOLs.     

Lens epithelial cell regression on the posterior capsule with different intraocular lens materials

BACKGROUND/AIMS—Posterior capsular opacification (PCO) is caused by proliferation and migration of lens epithelial cells (LECs) across the posterior capsule and is the commonest cause of reduced vision after cataract surgery. The influence of intraocular lens (IOL) material on the process of LEC migration was studied.
METHODS—90 eyes underwent standardised extracapsular surgery, with capsulorhexis and "in the bag" IOL placement. They were randomised to receive a three piece 6 mm lens of PMMA, silicone, or polyacrylic (AcrySof, Alcon, Fort Worth, TX, USA). On days 7, 30, 90, 180, and years 1 and 2 high resolution digitised retroillumination images were taken of the posterior capsule. The presence of LECs was determined at 90 days and 2 years, and their progression or regression was established by serial examination of images.
RESULTS—LECs were seen in 93% of silicone and 97% of PMMA IOLs at 90 days, compared with 46% of polyacrylic (p<0.001). At year 2 LECs were present in all patients with silicone or PMMA lenses, whereas 62% of patients with polyacrylic IOLs had LECs (p<0.001). Of those patients with LECs at day 90 LEC regression occurred in 8% with silicone IOLs and 15% of PMMA cases, compared with 83% of patients with polyacrylic IOLs (p<0.0001).
CONCLUSION—The presence of LECs on the posterior capsule was considerably lower with polyacrylic than PMMA or silicone IOLs and LEC regression occurred more frequently. The lower incidence of LECs and the higher rate of regression may explain why PCO formation appears to be reduced with polyacrylic lenses. This has important clinical implications for the prevention of PCO.

Keywords: lens; cell; implant; posterior capsular opacification     

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.