[To establish and observe the experimental lens regeneration model in rabbits].

PURPOSE: To establish the lens regeneration model in New Zealand rabbits, observe the lens regeneration process to investigate the mechanism of lens epithelial cell growth and lens regeneration.

METHODS: Lens extraction by endocapsular phacoemulsification was performed on 8 experimental eyes in New Zealand albino rabbits weighing approximately 1.5 - 2.5 kg. To restore a relative intact capsule bag, a little needle tip was inserted through the limbal wound to perform a 2 mm-lined anterior capsulotomy, which just permitted the insertion of a 21G phacoemulsification tip. Phacoemulsification extraction was applied to remove all lens cortical material and then Healon was injected intracapsularly to distend the capsule bag. With slitlamp, the procedure of le ns regeneration were observed and taken photographs. A histologic study on regenerated lens were also performed.

RESULTS: The relative 3 different results on experimental eyes according to the size of anterior capsulotomy in surgical procedure. In 4 eyes, when the size of anterior capsulotomy is approximately 2 mm and the capsule bag is relatively intact, lens regeneration occured and it has a relatively normal translucent cortex and central nuclear opacity. Among other 4 surgical eyes, the lower half part of lens regeneration was still observed in one eye though the upper half of anterior capsule was damaged, whereas in other 3, owing to the whole anterior capsule lack nearly, lens regrowth was not noted in areas of pupil under the slitlamp biomicroscopy observation and the posterior capsule appeared as gray-white membrane opacity. Histologic study showed that lens epithelial cells in equatorial zone proliferate and differentiate into lens fibers and continues to refill the whole capsule bag. Lens fiber alignment was regular in the periphery of regenerated lens, whereas in the center opacity nuclear, the bulk of the regenerated lens material consisted of an eosinophilic disorganized lens fibers. In addition, there were much of irregular cellular proliferation in capsule wrinkling.

CONCLUSION: Capsule is the support material of lens epithelial cells regrowth. Lens regeneration occurred in rabbits after restoring lens capsular integrity following endocapsule phacoemulsification lens extraction, which was the result of the lens epithelial cells proliferation and differentiation. The cellular proliferation and differentiation was associated with the of capsule morphosis.