Evaluation of intraocular lens mechanical stability
Stephen Lane1, Stephen Collins2, Kamal K Das2
1Associated Eye Care, University of Minnesota, Stillwater, Texas, USA; Alcon Laboratories, Inc., Fort Worth, Texas, USA.
Journal of Cataract and Refractive Surgery
|January 29, 2019
Summary
The Clareon CNA0T0 intraocular lens (IOL) demonstrated minimal axial displacement and simulated dioptric power shift compared to other monofocal IOLs. These findings suggest the CNA0T0 IOL may offer more consistent refractive outcomes for patients.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Materials Science
Background:
- Intraocular lenses (IOLs) are crucial for restoring vision after cataract surgery.
- Ensuring the mechanical stability and predictable performance of IOLs is essential for achieving optimal refractive outcomes.
- Comparing new IOL designs with established models is vital for clinical adoption.
Purpose of the Study:
- To compare the mechanical characteristics and stability of the Clareon CNA0T0 intraocular lens (IOL) against four existing monofocal IOLs.
- To evaluate the axial displacement and simulated dioptric power shift of the Clareon CNA0T0 IOL under varying compression diameters.
- To assess optic decentration and tilt in different IOL models.
Main Methods:
- An experimental study design was employed.
- Five IOL models (Clareon CNA0T0, AcrySof SN60WF, enVista MX60, Tecnis ZCB00, Vivinex iSert XY1) were tested, with 10 IOLs per group.
- Standardized methods (ISO11979-3) were used to measure axial displacement, optic decentration, and optic tilt, with axial displacement assessed across compression diameters from 9.0 to 11.0 mm.
Main Results:
- The Clareon CNA0T0 IOL exhibited significantly lower mean axial displacement (0.02 mm ± 0.01) at 10.0 mm compression compared to MX60, ZCB00, and XY1 IOLs (P < .005).
- Both CNA0T0 and SN60WF IOLs showed the lowest axial displacement and simulated dioptric power shift across all tested compression diameters.
- Optic decentration was similar across all IOLs (within ±0.06 mm at 10.0 mm compression), while the CNA0T0 IOL had significantly lower optic tilt than the MX60 IOL.
Conclusions:
- The Clareon CNA0T0 and AcrySof SN60WF IOLs demonstrated superior stability, evidenced by the lowest axial displacement and simulated dioptric power shift.
- These findings suggest that the CNA0T0 and SN60WF IOLs may provide more consistent and reliable refractive outcomes post-implantation.
- The mechanical characteristics of the CNA0T0 IOL support its potential as a stable option in monofocal IOL surgery.
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