A system (1) for treating and monitoring the condition of an eye (6) includes a light source, preferably a non-lasing LED (2), for irradiating the eye at a wavelength sufficient to reverse eye damage. The system also includes an excitation light source, preferably a non-lasing LED (4), for exciting fluorescence in the eye and a detector (22) for detecting fluorescence stimulated by the excitation LED (4). The system may also include a second non-lasing light source, preferably a non-lasing LED, for irradiating the eye； and a detector for detecting scatter of light from the eye. Methods for monitoring, diagnosis and treatment of eye conditions such as cataracts are also provided.
