Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) early-onset glaucoma ?
    ### Response:
    Glaucoma is a group of eye disorders in which the optic nerves connecting the eyes and the brain are progressively damaged. This damage can lead to reduction in side (peripheral) vision and eventual blindness. Other signs and symptoms may include bulging eyes, excessive tearing, and abnormal sensitivity to light (photophobia).
    