Evaluation of postoperative toric intraocular lens alignment with anterior segment optical coherence tomography

Abstract

We describe the use of a simple tool to evaluate the postoperative alignment of toric intraocular lenses (IOLs). The entire anterior segment is scanned using anterior segment optical coherence tomography and analyzed with an internal dedicated tool. A topographic map is displayed along with an anterior segment image, including a linear axis marker centered on the corneal apex. The marker can be rotated until it is aligned with the line connecting the IOL marking dots, precisely reproducing the IOL astigmatic axis, which is measured in angle degrees. The value of the IOL astigmatic axis is compared with the value of the astigmatic axis shown in real time on the same screen in the topographic map. Evaluating the alignment of a toric IOL axis simultaneously with the topographic astigmatic axis eliminates the potential errors that result from head tilting and strictly correlates with the astigmatic correction achieved.