Toric outcomes: Computer-assisted registration versus intraoperative aberrometry

Abstract

Purpose: To compare refractive outcomes of intraoperative computer-assisted registration and intraoperative aberrometry for the reduction of cylinder during toric intraocular lens (IOL) placement.

Setting: Bowie Vision Institute, Bowie, Maryland, USA.

Design: Prospective randomized case series.

Method: The patients were divided into 2 groups that had toric IOL implantation after phacoemulsification. The intraoperative computer-assisted registration group (Group 1) had preoperative toric calculations. The aberrometry group (Group 2) was guided by a vergence formula and intraoperative pseudophakic cylindrical measurements to determine the final IOL power and intended orientation. The primary outcome measure was the mean postoperative remaining refractive astigmatism, and it was compared with the predicted amount of cylindrical correction with the IOL.

Results: Fifty-two patients (104 eyes) had sequential cataract surgery. The mean amount of cylinder correction was 1.60 diopters (D) ± 0.70 (SD) (range 0.75 to 3.08 D) in Group 1 and 1.74 ± 0.79 D (range 0.72 to 3.08 D) in Group 2. The mean remaining refractive astigmatism was -0.29 ± 0.22 D in Group 1 and -0.46 ± 0.25 D in Group 2 (P = .0003). A difference vector of 0.1 @ 87 degrees (0.31 D arithmetic mean) was calculated in Group 1 and 0.0 @ 82 degrees (0.44 D arithmetic mean) in Group 2. The correction index was 1.03 in Group 1 and 0.95 in Group 2.

Conclusion: Intraoperative markerless computer-assisted registration and biometric guidance summarily yielded less remaining refractive cylinder than toric IOL placement guided by intraoperative aberrometry.