Purpose: To compare 4 different secondary intraocular lens (IOL) fixation techniques regarding the least required force to dislocate a scleral fixated 3-piece IOL in human corneoscleral donor tissue.
Design: Experimental laboratory investigation.
Methods: The least required dislocation force (LRDF) of 4 different secondary IOL fixation techniques, namely, the techniques using transscleral tunnels (TTs; as described by Scharioth), glued haptics (GHs; Agarwal), flanged haptics (FHs; Yamane), and bent haptic ends (BH; Behera/Bolz), were investigated using 40 three-piece IOLs (Sensar AR40) fixated to human scleral tissue. The main outcome of the study, dislocation force between different techniques, was measured with a tensiometer.
Results: The force needed to dislocate the haptics was highest with the FH technique and was significantly higher than with all the other techniques (GH vs FH: -1.02±0.02 N, P < .001; TT vs FH: -1.08±0.21 N, P < .001; BH vs FH: -1.00±0.25 N, P = .044). There was no significant difference regarding the dislocation force between the other techniques: GH vs TT (-0.06±0.100 N, P = .988), GH vs BH (-0.02±0.03 N, P = .60), TT vs BH (-0.08±0.04 N, P > .99).
Conclusions: The FH technique as described by Yamane proved to be the strongest form of secondary IOL fixation regarding dislocation force in this in vitro study. The other fixation techniques showed significantly less resistance to axial traction.
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