%0 Journal Article
%T Dislocation force of scleral flange-fixated intraocular lens haptics.
%A Stunf Pukl S
%A Kronschläger M
%A Ruiss M
%A Blouin S
%A Akcan ER
%A Findl O
%J BMC Ophthalmol
%V 24
%N 1
%D 2024 Mar 5
%M 38443841
%F 2.086
%R 10.1186/s12886-024-03369-x
%X OBJECTIVE: To measure the dislocation forces in relation to haptic material, flange size and needle used.
METHODS: Hanusch Hospital, Vienna, Austria.
METHODS: Laboratory Investigation.
UNASSIGNED: 30 G (gauge) thin wall and 27 G standard needles were used for a 2 mm tangential scleral tunnel in combination with different PVDF (polyvinylidene fluoride) and PMMA (polymethylmethacrylate haptics). Flanges were created by heating 1 mm of the haptic end, non-forceps assisted in PVDF and forceps assisted in PMMA haptics. The dislocation force was measured in non-preserved cadaver sclera using a tensiometer device.
RESULTS: PVDF flanges achieved were of a mushroom-like shape and PMMA flanges were of a conic shape. For 30 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 1.58 ± 0.68 N (n = 10) and 0.70 ± 0.14 N (n = 9) (p = 0.003) respectively. For 27 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 0.31 ± 0.35 N (n = 3) and 0.0 N (n = 4), respectively. The flange size correlated with the occurring dislocation force in experiments with 30 G needle tunnels (r = 0.92), when flanges were bigger than 384 micrometres.
CONCLUSIONS: The highest dislocation forces were found for PVDF haptic flanges and their characteristic mushroom-like shape for 30 G thin wall needle scleral tunnels. Forceps assisted flange creation in PMMA haptics did not compensate the disadvantage of PMMA haptics with their characteristic conic shape flange.