Anterior segment OCT useful for calculating IOL tilt, decentration

November 15, 2006

London-Anterior segment optical coherence tomography (AS-OCT) (Visante OCT system, Carl Zeiss Meditec) can be used to calculate IOL tilt and decentration and may have an advantage of being able to provide accurate measurements in eyes with an irregular pupil or cornea, said Richard Lee, BSc.

At the XXIV Congress of the European Society of Cataract and Refractive Surgeons, Lee presented experience using the AS-OCT device to calculate postoperative IOL tilt and decentration in a series of 20 consecutive patients who had undergone routine phacoemulsification and endocapsular IOL implantation with several different IOL models. Only patients with uneventful surgery and without zonular weakness or corneal abnormalities were enrolled.

For the 20 eyes evaluated, mean ± SD total tilt was 2.51° ± 1.82° posterior nasal-inferiorly, and mean total decentration was 0.331 ± 0.283 mm nasal-inferiorly. In the horizontal meridian, the average decentration was 0.214 ± 0.108 mm nasally, and the mean tilt was 1.61° ± 1.20° nasally. Average decentration in the vertical meridian was 0.252 ± 0.202 mm inferiorly, and average posterior tilt was 1.92° ± 1.36° inferiorly.