Comparison of the Rotational Stability of Two Toric Intraocular Lenses in 1273 Consecutive Eyes
1Altos Eye Physicians, Los Altos, California.
Purpose:
To compare the rotational stability of the 2 most commonly used toric intraocular lenses (TIOLs).
Design:
Retrospective cohort study in a single private practice.
Subjects:
The study included all patients receiving an Acrysof (n = 626) or Tecnis TIOL (n = 647) over an 18-month period from April 2015 to September 2016. Patients were only excluded if their surgery could not be performed using a digital marking system.
Methods:
All patients had cataract surgery performed in the same surgical center with a similar technique. A digital marking system with limbal vessel registration was used to record the axis of the TIOL at the conclusion of surgery. A dilated examination was performed either later on the day of surgery or the next morning, and the postoperative rotation of the 2 TIOL models was compared. Patients who required a return to the operating room for TIOL repositioning were examined to determine risk factors for reoperation and subsequent outcomes.
Main Outcome Measures:
The primary outcome measure was the percentage of eyes with TIOL rotation >5 and >10 degrees. The second main outcome was likelihood of requiring return to the operating room to reposition a rotated TIOL.
Results:
The Acrysof TIOL was less likely to rotate postoperatively, with 91.9% of eyes rotated ≤5 degrees at the first postoperative check compared with 81.8% of Tecnis TIOL eyes (P < 0.0001). This difference persisted for rotation ≤10 degrees (97.8% Acrysof vs. 93.2% Tecnis, P = 0.0002) and ≤15 degrees (98.6% Acrysof vs. 96.4% Tecnis, P = 0.02). The mean rotation was 2.72 degrees (95% confidence interval 2.35-3.08 degrees) for Acrysof and 3.79 degrees (95% confidence interval 3.36-4.22 degrees) for Tecnis TIOLs (P < 0.05). The Tecnis TIOL showed a strong predisposition to rotate counterclockwise, unlike the Acrysof. More Tecnis TIOL patients required repositioning (3.1% vs. 1.6%), but this did not reach statistical significance (P = 0.10). Refractive outcomes were similar between the 2 groups.
Conclusions:
The Acrysof TIOL showed significantly greater rotational stability than the Tecnis TIOL.
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