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Purpose: To quantify implantation-induced mechanical stress on the capsular–zonular complex using image-based analysis and to compare force transmission patterns between a novel capsular tension ring–based device (fixOflex) and standard intraocular lenses (IOLs).

Methods: Capsular bag interactions of the circular fixOflex, a one-piece C-loop IOL, and a plate-haptic IOL were analyzed in human postmortem eyes using Fiji. Maximal capsular bag expansion, zonular strain, and capsular bag occupancy were quantified using the Miyake–Apple view. The Choi–Apple view enabled three-dimensional assessment of capsular–zonular deformation during implantation.

Results: Force transmission patterns differed by implant geometry. The C-loop IOL transmitted forces through a focal point at the leading haptic, whereas the plate-haptic IOL exhibited two contact regions, both resulting in a predominantly sagittal expansion. In contrast, the circular fixOflex distributed injection forces across multiple contact points, resulting in comparable sagittal and equatorial capsular deviations. Accordingly, zonular stress differed between implants: the C-loop IOL showed the highest zonular strain (2.73 mm²) and peak capsular-zonular deviation (117.01%), followed by the plate-haptic IOL (1.88 mm² and 81.18%) and the fixOflex (1.79 mm² and 80.76%). Capsular bag expansion primarily reflected tissue compliance. Capsular bag occupancy was lowest for the C-loop IOL and highest for the fixOflex (54.41% vs 95.07%).

Conclusions: Implantation patterns and stress are determined by implant geometry and resulting force transmission rather than overall implant size. The presented approach enables visualization of otherwise inaccessible processes and provides clinically relevant insights for challenging capsular bag conditions, guiding clinical application and future implant development.