Toric outcomes: Computer-assisted registration versus intraoperative aberrometry

Area of Science:

• Ophthalmology
• Refractive Surgery
• Biomedical Engineering

Background:

• Toric intraocular lenses (IOLs) are used to correct astigmatism during cataract surgery.
• Accurate IOL alignment is crucial for effective astigmatism reduction.
• Intraoperative guidance systems aim to improve the precision of toric IOL placement.

Purpose of the Study:

• To compare the refractive outcomes of two intraoperative guidance techniques for toric IOL placement.
• To evaluate the effectiveness of computer-assisted registration versus intraoperative aberrometry in reducing residual astigmatism.
• To determine which method leads to better visual acuity post-surgery.

Main Methods:

• A prospective randomized case series involving 52 patients (104 eyes) undergoing cataract surgery with toric IOL implantation.
• Group 1 (computer-assisted registration) used preoperative toric calculations.
• Group 2 (intraoperative aberrometry) used vergence formulas and intraoperative measurements for IOL power and orientation determination.

Main Results:

• The mean remaining refractive astigmatism was significantly lower in the computer-assisted registration group (-0.29 D) compared to the aberrometry group (-0.46 D) (P = .0003).
• The difference vector, representing the magnitude and axis of residual astigmatism, indicated better correction with computer-assisted registration.
• The correction index favored the computer-assisted registration group, suggesting more accurate refractive outcome prediction.

Conclusions:

• Intraoperative markerless computer-assisted registration provides superior outcomes in reducing residual refractive cylinder compared to intraoperative aberrometry during toric IOL placement.
• Computer-assisted guidance may enhance the precision of toric IOL alignment, leading to improved refractive results.
• These findings support the use of computer-assisted registration for optimizing astigmatism correction in toric IOL surgery.