Ophthalmology is the branch of medicine that studies the anatomy, physiology, and
diseases of the eye. Ophthalmologists detect
and treat such vision
disorders as myopia, presbyopia, and astigmatism, and eye
diseases, including infections such as conjunctivitis and trachoma (a bacterial disease found mostly in developing countries), tumors in the interior of the eye, and cataracts and glaucoma, significant causes of blindness. They may use drugs or surgery to treat eye diseases. A wide array of instruments are available to help the ophthalmologist make a diagnosis. Ophthalmologists are different from optometrists, who are trained and licensed to detect and treat vision disorders and to diagnose eye diseases.