Open-capsule intraocular lens to prevent posterior capsule opacification

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

Preliminary results of cataract extraction with implantation of a single-piece AcrySof intraocular lens

Evaluation of a new single-piece 4% water content hydrophobic acrylic intraocular lens in the rabbit model

Postoperative capsular opacification is a multifactorial physiological consequence of cataract surgery. Opacification involving the central posterior capsule has a significant impact on high- and low-contrast acuity and low-contrast sensitivity. The proliferation, migration and abnormal differentiation of residual lens epithelial cells and fibers in the capsular bag have been implicated in the pathogenesis of posterior capsule opacification (PCO). The incidence and severity of PCO correlates to the use of surgical techniques, intraocular lens optic edge designs and intraocular lens materials. This article summarizes the clinical studies with recommendations for retarding the development of central PCO. These studies will remain critical for future endeavors undertaken for the eradication of PCO.

Pediatric cataract surgery and intraocular lens implantation techniques: A laboratory study

Effect of tranilast eyedrops in preventing posterior capsule opacification: preliminary report

Capsular bag opacification with a new accommodating intraocular lens

Role of vitrectomy with optic capture

A 3D in vitro model for assessing the influence of intraocular lens: Posterior lens capsule interactions on lens epithelial cell responses

Randomized intraindividual comparison of posterior capsule opacification between a microincision intraocular lens and a conventional intraocular lens

To evaluate the effect of multiquadrant cortical cleaving hydrodissection on the development of posterior capsule opacification (PCO) after phacoemulsification. Iladevi Cataract and IOL Research Center, Ahmedabad, India. A prospective randomized triple blind clinical trial was conducted in 86 eyes (86 patients) having phacoemulsification. Eyes were assigned randomly to Group 1, multiquadrant cortical cleaving hydrodissection and hydrodelineation (n = 48 eyes), or Group 2, no multiquadrant cortical cleaving hydrodissection, only hydrodelineation (n = 38 eyes). Age-related nuclear sclerosis (grading system of 1 to 5) and age greater than 50 years were included. Diabetes mellitus and associated eye diseases were excluded. Standard phacoemulsification with implantation of an AcrySof MA30BA intraocular lens (IOL) was done in both groups. High-resolution digital retroillumination images of the posterior capsule were analyzed at 4 years using POCOman software. Seven patients dropped out (8.1%). Outcome measures were incidence and percentage area of PCO. Test of proportions, independent sample t test, and 95% confidence intervals (CIs) were noted. In Groups 1 and 2, the mean age was 58 years +/- 4 (SD) and 57 +/- 5 years, respectively (P = .702; 95% CI, 1.90-2.81); mean follow-up was 48.4 +/- 2.5 months and 49.3 +/- 1.9 months, respectively (P = .687; 95% CI, 1.186-0.7856); incidence of PCO was 11 of 44 (25%) and 12 of 35 (34.3%), respectively (P = .317; 95% CI, 0.359-0.0889); percentage area of PCO was 14.3% and 25.6%, respectively (P = .006; 95% CI, -19.19 to -3.44). One of 44 eyes (2.27%) and 2 of 35 eyes (5.7%) in the groups, respectively, had a neodymium:YAG capsulotomy. Although no difference was noted in the incidence of PCO, in eyes that had PCO, the percentage of the area of the central posterior capsule involved by PCO was significantly lower in eyes that had multiquadrant cortical cleaving hydrodissection than in those that did not.

To establish a fully human in vitro culture model with which to test the putative effects of intraocular lens (IOL) designs in preventing posterior capsule opacification (PCO) after cataract surgery. A sham cataract operation was performed to prepare human capsular bags from donor lenses. In one capsular bag of a donor pair, an intraocular lens (PMMA round-edge IOL or acrylic IOL) was implanted while the other capsular bag remained aphakic. Bags were transferred to a Petri dish and secured anterior-face down using entomological pins. Capsular bags were maintained in Eagle's minimum essential medium supplemented with 2% human serum and 10 ng/mL TGF-β to drive growth and matrix contraction. In the absence of an IOL, cells appeared within the central posterior capsule at 4.38 ± 0.26 days, whereas in the presence of a PMMA round-edge IOL or an acrylic IOL they appeared at 8 ± 0.41 days and 11 ± 0.7 days, respectively. Immunocytochemical analysis showed an accumulation of cells at the edge of the acrylic IOL and a less evident accumulation with the PMMA round-edge IOL. Moreover, matrix contraction was more prominent in the absence of an IOL but was still apparent, to a lesser degree, in the presence of a PMMA round-edge IOL. The acrylic IOL greatly suppressed matrix contraction. The authors have developed a fully human in vitro capsular bag system that relates well to clinical observations and permits the testing of novel intraocular lenses.

Effect of total lens epithelial cell destruction on intraocular lens fixation in the human capsular bag

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

Despite recent improvements in intraocular lens (IOL) design, posterior capsule opacification (PCO) arising from lens cell growth remains a major problem. Calcium signaling has been shown to play a major role in driving human lens cell growth, and therefore it is necessary to understand the underlying mechanisms. Calcium signaling was studied in capsular bags (ex vivo) removed from donors who had undergone earlier cataract surgery. Fresh capsular bags were also produced from intact donor lenses and cultured in serum-free EMEM for up to 8 weeks. Both preparations were loaded with Fura-2, and ratiometric imaging of cytoplasmic calcium was performed using epifluorescence techniques. Changes were monitored in response to 10 microM ATP (adenosine triphosphate), 10 microM acetylcholine, and 10 ng/mL epidermal growth factor (EGF), and data were collected from equatorial, posterior, and anterior regions. Calcium transients were also recorded from anterior epithelial specimens in response to pilocarpine. All equatorial cells of ex vivo bags responded to ATP and EGF, but not to acetylcholine, and this pattern was maintained in the cultured bags. Posterior capsule cells of both preparations also had similar properties, in which a large proportion of the cells responded to ATP and EGF, but not to acetylcholine. Conversely, most anterior cells of the in vivo bags responded to pilocarpine, whereas no cells in the cultured bags responded. All cells in the fresh anterior epithelium responded to pilocarpine. Ex vivo capsular bags retain the region-specific calcium-signaling characteristics of the native lens. Apart from losing M1 muscarinic expression properties, the in vitro capsular bags also reflect region-specific signaling properties and therefore provide a good model for the investigation of the contribution of calcium-signaling to PCO.