[Experimental studies of the risks of endocapsular polymerization of injectable intraocular lenses]

Various experimental lens refilling procedures have been proposed. One of these methods uses endocapsular polymerization of the injected material by light exposure. In this study we wanted to characterize the potential risks of this procedure due to light and temperature hazards. We performed in vitro experiments on enucleated pig eyes and an in vivo study on 15 rabbits. During the polymerization process the highest temperature recorded (45.1 degrees C) was measured at the posterior lens capsule for a few seconds. The measured irradiance (0.065 W/cm2) and the risk of photochemical damage to the retina during 20 s of polymerization was comparable to that caused by 1.5 min of standard coaxial illumination with our operating microscope. In vivo we found no serious inflammatory reactions except for four cases where surgical problems had occurred. No direct retinal damage could be detected histopathologically. In conclusion, we think that lens refilling and endocapsular polymerization are promising techniques. However, refilling materials with better physical properties than those available so far need to be developed.