Purpose:
After refilling the capsular bag of a monkey eye with an injected polymer lens refilling accommodating IOL, a capsular opacification may occur. The purpose of this study was to demonstrate that this capsular opacification is also dependent on the capsular filling material.
Methods:
The natural lenses of 2 iridectomized rhesus monkey eyes were removed through a 1.5 mm peripheral capsulorhexis, and the capsular bags were treated for 5 minutes with a viscoelastic solution in pure water containing Actinomycin-D. Composition and method were selected from in vitro (human rhexis material) and in vivo studies (rabbits) as an effective method against lens epithelial cell (LEC) proliferation. The capsular bag of Monkey A’s left eye was filled with a silicone-based pre-polymer mixture that cures in-situ. The capsular bag of Monkey B’s left eye was filled with a viscoelastic sodiumhyaluronate solution (Healon OVD) and closed with a silicone plug. After 3 months the Healon was replaced with the same silicone-based material that was used in Monkey A. The cleanliness of the eyes was inspected with a slit lamp and under a surgical microscope. When possible, the refraction of the eyes was measured with a Hartinger refractometer before and after pharmacological stimulation of accommodation. The lens thickness was measured with A-scan and corrected for the speed of sound through the artificial lens material (1066 m/s).
Results:
Three months post-operatively, slit lamp pictures in the eye of Monkey A showed clear signs of beginning opacification. The Healon-filled capsular bag of Monkey B showed a good lens shape and no signs of opacification three months post-op. Within 4 weeks after replacing the Healon with silicone material traces of opacification could already be detected and lens thickness changes after pilocarpine-stimulated accommodation decreased from 0.35 mm at 1-month post-op to 0.09 mm at 8 months post-op.
Conclusions:
With Healon OVD as a capsular filling material in monkey eyes, the LECs did not react. However, when the LECs were in contact with artificial silicone-based lens material, a kind of foreign body reaction was observed.
Keywords: accomodation • posterior capsular opacification (PCO) • intraocular lens