The invention relates to a system and a method for the treatment of a patients eye. The system comprises a laser apparatus, a scanning apparatus and an eye tracking apparatus for determining the actual position of the patients eye and for generating alignment data of the patients eye relative to a reference position of the patients eye to the laser, said eye tracking apparatus being provided with a desired treatment shot file. Said scanning apparatus is connected via a first bidirectional bus to the eye tracking apparatus, said laser apparatus is connected via a second bidirectional bus to the eye tracking apparatus. The eye tracking apparatus adjusts the position data for each shot based on said alignment data of the patients eye and provides aiming control signals representative of the target position data to the scanning apparatus for said shot via said first bidirectional bus. The eye tracking apparatus comprises a comparator for comparing the target position data with the actual position data provided by the scanning apparatus for the shot to be fired. Moreover, said eye tracking apparatus is sending a command signal to the laser apparatus via said second bidirectional bus for firing the shot when the target position data is equal to the actual position data of the scanning apparatus for the shot to be fired.