Evaluation of an intraoperative toric intraocular lens alignment system using an image-guided system

To evaluate an intraoperative toric intraocular lens (IOL) alignment system using a dedicated operating microscope with an image-guided system without preoperative corneal marking.

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

Prospective case series.

In this prospective study, a new operating microscope system was used for cataract surgery (toric IOL alignment system of the OPMI Lumera 700 microscope and CALLISTO eye software). This system allows toric IOL alignment by matching limbal vessels from a preoperative photograph with the live image of the microscope. The preoperative photograph was taken with IOLMaster 500, which included a "Reference Image Attachment" system (red-free image), and this was used to track and follow the eye during surgery. After surgery, rotational alignment was assessed and compared with the preoperative axis calculation. At 1 hour postoperatively, a retroilluminaton photograph was taken, and then rotational alignment was compared with the preoperative axis calculation to see the rotational stability.

Fifty eyes of 50 patients were included. The feasibility of the intraoperative marking was high. Deviation between the postoperative (at the end of surgery in the operating room) and aimed IOL axes was 0.52 degrees ± 0.56 (SD). The deviation between 1 hour postoperatively and the aimed IOL axes was 5.10 ± 4.45 degrees.

Intraoperative toric IOL alignment using an image-guided system was an accurate and fast procedure resulting in precise toric IOL alignment, and the system simplified the positioning of toric IOLs. There was a slight rotation of IOLs shortly after surgery (within the first hour).