FIXATION ELEMENTS ON PLATE INTRAOCULAR-LENS - LARGE POSITIONING HOLESTO IMPROVE SECURITY OF CAPSULAR FIXATION

Objective: This study aimed to evaluate in rabbit eyes the effects of large positioning holes in one-piece silicone plate-haptic intraocular lenses (IOLs) with respect to security of capsular bag fixation. Mech anical strength of capsular fixation is correlated with the histologic findings of regenerating lens material and fibrous tissue ingrowth th rough the positioning holes on silicone plate IOLs, comparing capsules implanted with large-hole style plate IOLs to fellow capsules implant ed with small-hole style plate IOLs. Design: The study design was a pr ospective, randomized, experimental study. Participants: A total of 40 fellow capsular bags from 20 New Zealand white rabbits were examined. Capsules implanted with conventional small-hole silicone plate IOLs w ere used as the control in all pairs of fellow capsules. Intervention: Phacoemulsification and implantation of a silicone plate IOL with sma ll positioning holes in one eye and implantation of a silicone plate I OL with large positioning holes in the fellow eye were measured. All r abbits were killed at 2 months. The force required to extract the IOLs from the capsular bag was measured. All capsular bags underwent histo pathologic analysis. Main Outcome Measures: Extraction force measureme nts and histopathologic examination, comparing capsules implanted with small-hole plate IOLs with fellow capsules implanted with large-hole plate IOLs, were measured. Results: The large-hole style IOL required significantly more force to extract from the capsular bag compared to the conventional small-hole style (P = 0.003). Histologically, prolife rating lens epithelial material and fibrous tissue were observed growi ng through all of the large positioning holes (synechia formation) but not through any of the small positioning holes. Conclusions: Silicone plate IOLs with large positioning holes become affixed more firmly wi thin the capsular bag compared to conventional small-hole plate IOLs, These findings suggest that large holes in silicone plate IOLs allow f or superior capsular bag fixation, This should reduce the rates of dec entration and dislocation.