Devices and approaches for activating cross-linking within corneal tissue to stabilize and strengthen the corneal tissue following an eye therapy treatment. A feedback system is provided to acquire measurements and pass feedback information to a controller. The feedback system may include an interferometer system, a corneal polarimetry system, or other configurations for monitoring cross-linking activity within the cornea. The controller is adapted to analyze the feedback information and adjust treatment to the eye based on the information. Aspects of the feedback system may also be used to monitor and diagnose features of the eye 1. Methods of activating cross-linking according to information provided by a feedback system in order to improve accuracy and safety of a cross-linking therapy are also provided.
