An experimental study of the surgical trauma on the rabbit's lens suspensory apparatus after cataract surgery]

Extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PC-IOL) implantation requires that the posterior capsule and the zonules remain sufficiently intact. To assess the surgical trauma on the lens suspensory apparatus of the enucleated rabbit eye, we developed a new fine pressure gauge that could quantitate its strength. The cornea and the iris of enucleated eyes were removed to allow clear visualization of the anterior surface of the lens to the equator. Afterwards several types of anterior capsulotomy were performed for ECCE and PC-IOL implantation. And then the lens of the pseudophakic eye was vertically pressed with the plastic rod of the fine pressure transducer, and the strength of the lens suspensory apparatus was simultaneously measured. The strength of the lens suspensory apparatus of the pseudophakic eye decreased approximately 35% compared with that of the phakic eye. Moreover the integrity of the lens capsule of animals with circular capsulorhexis with tears or linear capsulotomy decreased approximately 43% compared with that of continuous circular capsulorhexis (CCC) and also zonular rupture and vitreous loss occurred as a result of the expansion of radial tears in the anterior capsule. The present study indicates that the strength of the lens suspensory apparatus decreases with cataract surgery, suggesting that much more attention to cataract surgery is needed if the anterior capsule had radial tears. It is also suggested that CCC is the best type of anterior capsulectomy procedure.