Comparison of toric intraocular lens alignment error with different toric markers

To compare the error in intraocular lens (IOL) toric alignment of 2 toric markers.

Sir Charles Gairdner Hospital, Perth, Western Australia, Australia.

Retrospective case series.

Two consecutive groups of patients had cataract surgery with implantation of an AcrySof SN6A toric IOL (versions T2-T8) by the same surgeon at 2 public hospitals. The only difference in the toric alignment method between the groups was the toric maker used (Group 1: Barrett dual axis toric marker; Group 2: Mendez gauge). A mobile phone application (toriCAM) was used in both groups to determine the reference meridian. The primary outcome measure was the error in toric IOL alignment in degrees at 1 month. The secondary outcome measure was the percentage of eyes achieving a manifest refraction astigmatism within ±0.50 diopter (D) at 1 month.

Seventy-two eyes of 56 patients were included (Group 1: 36 eyes of 35 patients; Group 2: 36 eyes of 25 patients). The mean absolute toric alignment error (intended versus achieved axis of alignment) was 4.0 degrees ± 2.9 (SD) in Group 1 and 8.4 ± 6.5 degrees in Group 2 (P = .0015). Twenty-nine eyes (80.6%) in Group 1 and 21 eyes (53.8%) in Group 2 achieved a manifest refractive astigmatism of 0.50 D or less (P < .05).

Toric IOL alignment using the mobile phone application was more accurate with the Barrett dual axis toric marker than with the commonly used Mendez gauge, with a significantly higher percentage of eyes achieving a manifest refraction astigmatism within ±0.50 D.