What is the VISX® Star S4 Active Trak®
Excimer Laser System?

This laser delivery system represents a whole new dimension in technology, accuracy, and safety in laser vision correction.

What makes the VISX® Star S4 laser system unique?

It is the world's only laser vision correction system that combines the safety of 3 dimensional active eye tracking, the accuracy and customization of variable sized beams for speed and smoothness, and the comfort and quicker recovery of a non-dilated pupil. Additionally, its laser treatment zone is now wider than almost all pupils and is the only laser with computerized centration. This should dramatically decrease the incidence of glare and halo after LASIK eye surgery.

The VISX® Star S4 tracker works along the x, y and z axis. All other laser trackers are 2 dimensional trackers along the x and y axis. The variable sized beams offer a great advantage in the speed of laser eye surgery. The faster a laser works, the less dehydration occurs, which yields more accurate results and smoother treatments. The best way to think of this is in carving a block of marble. Initially, large chisels are used to contour the block. This is analogous to large beam sizes. When it is time to create the fine details of the sculpture, smaller and more delicate chisels are used. The smaller excimer laser beam spots are small chisels. If small beam sizes were used throughout, then the LASIK procedure would be much longer and less accurate.

The unique tracking system of the VISX® Star S4 is performed without the need to dilate your pupil. A non-dilated pupil is more comfortable during the procedure and patients have a more rapid return of sharp vision.