Iris imaging software may improve accuracy of centration with toric IOLs

SAN FRANCISCO — Iris scanning software allows pinpoint measurement of corneal architecture that better allows surgeons to center toric IOLs.

Robert H. Osher

The imaging software, currently in development, captures a high-resolution picture of the iris, and the major meridians are identified using the narrow and horizontal slit beam, according to Robert H. Osher, MD. The software then superimposes the axes, an adjustable goal line and the exact degree of any iris landmark, such as nevi, dark zones and stromal spots.

Dr. Osher said he brings a hard copy of the image into the operating room and transfers the software-produced markers onto the iris using a degree marker. The company that is making the software, Micron Imaging Services, is working on a newer version that will transfer the image directly to the microscope view field.

"I think this is long overdue," Dr. Osher said. "I know on every iris, without marking, exactly where I am at all times, and now I can orient my toric lenses precisely."

In a study that he performed looking at the accuracy of a marking pen in measuring the horizontal meridian, Dr. Osher found that he missed his intended target by 13°. "Each degree is 3.3%, and so I've lost half the effect of my toric lens," he said.