DESIGN AND DEVELOPMENT OF A NEW 193-NANOMETER EXCIMER-LASER SURGICAL SYSTEM

BACKGROUND: The 193-nanometer excimer laser is used for photoablative reprofiling of the cornea to correct refraction errors and to treat co rneal pathologies. To use the unique properties of the excimer laser, some technical features should be provided by the excimer laser system . A new excimer laser system is presented. METHODS: The instrument has a fluence sensor for precise measurement of the actual fluence just b efore surgery, a new delivery system including an integrator system to homogenize the laser beam, a steelband with apertures and a zoom opti c to get the desired form of central reprofiling, and an alignment sys tem to reduce the possibility to decenter the optical zone. RESULTS: T he fluence before surgery can be measured very precisely with the flue nce sensor. The ablation zone size is at least 8 mm in diameter with a homogenous laser beam profile resulting in a smooth surface of the tr eated material. Different forms of ablations can be created using the steelband with different forms of apertures. The center of the ablatio n zone can be found using the alignment system. CONCLUSION: The new ex cimer laser system fulfills some important technical features for opti mal use of the excimer laser in corneal surgery.