AUG 30, 2017
This prospective study compared the accuracy of an automated toric IOL alignment technology with conventional manual ink-marking.
Patients with regular corneal astigmatism of at least 1.25 D requiring cataract surgery were randomly assigned to either manual marking or digital marking using the Alcon Verion system.
At both 1 hour and 3 months postop, eyes in the digital group showed better alignment compared with manual marking (P<0.05). Misalignment ranged from 0 to 6.1 degrees in the digital group, and 0.3 to 6.5 degrees in the manual marking group. Approximately 94% of the digital group and 81% of the manual group had misalignment of less than 5 degrees at month 3 (P=0.02).
There was no difference in mean UDVA or residual refractive astigmatism between groups, however, possibly because of low levels of baseline corneal astigmatism within the cohort.
This study was underpowered (36 eyes of 24 patients) to determine differences in manifest refraction cylinder or uncorrected visual acuity. The procedures were performed by 2 surgeons, who might have had differences in manual marking technique and accuracy that could be significant with a small sample size. And while alignment was significantly better in the digital group, the difference at 1-hour postop was only 1.5 degrees.
Although this study is small, it contributes to the growing evidence that digital marking systems are more accurate than manual ones for toric IOL marking and alignment.