J Korean Med Sci.  2007 Jun;22(3):502-507. 10.3346/jkms.2007.22.3.502.

The Efficacy of an Acrylic Intraocular Lens Surface Modified with Polyethylene Glycol in Posterior Capsular Opacification

• Lee HI
• Kim MK
• Ko JH
• Lee HJ
• Wee WR
• Lee JH

• KMID: 1778361
• DOI: http://doi.org/10.3346/jkms.2007.22.3.502

Abstract

To investigate if the surface modification of intraocular lens (IOL) is efficient in the prevention of posterior capsular opacification (PCO), the acrylic surface of intraocular lens (Acrysof(R)) was polymerized with polyethylene glycol (PEG-IOL). The human lens epithelial cells (1x10(4) cells/mL) were inoculated on PEG grafted or unmodified acrylic lenses for the control. The adherent cells on each IOL surface were trypsinized and counted. The every PEG-IOL was implanted in 20 New Zealand rabbits after removal of crystalline lens. The formations of PCO were checked serially through retroilluminated digital photography, and the severity scores were calculated using POCOman(R). The cell adherence patterns on each IOL were examined by scanning electron microscopy. As a result, the mean number of adherent cells of PEG-IOL (3.2+/-1.1x10(3)) tended to be smaller than that of the acrylic controls (3.6+/-1.9x10(3)) without a statistical significance (p=0.73). However, the mean severity of PCO formation in PEG-IOL was significantly lower than that in the control during the third to sixth weeks after surgery. Scanning electron microscopy revealed that the more patch-like cells were found firmly attached to the IOL surface in control than in the PEG-IOL. Conclusively, PEG polymerization to the acrylic IOL would possibly lessen the formation of PCO after cataract removal.

Keyword

Acrylates; Cataract; Lenses Intraocular; Polyethylene Glycols

MeSH Terms

Acrylic Resins/chemistry
Biocompatible Materials
Cataract/metabolism/*therapy
Cell Adhesion
Humans
Lens Implantation, Intraocular/*methods
Lens, Crystalline/cytology/ultrastructure
Microscopy, Electron, Scanning
Polyethylene Glycols/*chemistry/metabolism
Time Factors

Figure

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  Fig. 1 The severity grades of posterior capsular opacification with the POCOman software. A retroilluminated picture (A) is transformed into a black and white picture (B). The margin of the anterior capsule should be marked then the grid is allocated automatically. Using the standard photographies (grade 1-3), the severity score is calculated with the formula as follows: severity score=(3*Red [grade3]+2*Yellow [grade2]+1*Blue [grade1]/total area).

• 

  Fig. 2 In vitro human lens epithelial cell adhesion after 24-hr culture. The averaged number was slightly higher in the control than that of PEG grafted lens without statistical significance. p=0.73 by Mann whitney-U test.

• 

  Fig. 3 The formation of posterior capsular opacification (PCO) after implantation of intraocular lens in rabbits. (A) Polyethylene glycol (PEG), (B) Control. At the 3rd week, the fine fibrotic materials were found on the posterior capsule with minimal proliferation of lens epithelial cells (LECs) in comparison with the control, where the conglomerated LEC's were dominant. (C) The severity of PCO was significantly lower from the third week in the PEG group until the sixth week of examination. *, p<0.05 by Mann Whitney-U test.

• 

  Fig. 4 An enormous proliferation of lens epithelial cells through the optic-haptic junction. (A) 4th week. Few cells were seen except small cell buds at the optic-haptic junction (arrowhead). (B) 6th week. The cell nests were rapidly growing and threatening the visual axis. (C) 8th week. The visual axis was completely obliterated by enormously proliferating cells.

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  Fig. 5 The scanning electron microscope of adherent cells (×200 fold). (A) In the control group, spindle shape, patch-like cells, together with a few small round cells, were firmly attached to lens surface. (B) In the polyethylence glycol (PEG) group similar cells were found but seemed less adherent.

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