Optometry is a health care profession concerned with the health of the eyes and related structures, as well as vision, visual systems, and vision information processing in humans. Optometrists are trained to prescribe and fit lenses to improve vision, and to diagnose and treat various eye diseases. In the United States and Canada optometrists are considered Doctors of Optometry and are held to the same legal standards as any physician. In all U.S. states optometrists are licensed to diagnose and treat diseases of the eye through topical diagnostic and therapeutic drugs, and oral drugs in 47/50 states. Doctors of Optometry are also able to perform certain types of laser surgery in some states. In other countries patients are referred to other healthcare professionals, such as ophthalmologists, neurologists and general medical practitioners for further treatment or investigation.
The term "optometry" comes from the Hellenic (Greek) words ὄψις (opsis; "view") and μέτρον (metron; "something used to measure", "measure", "rule"). The root word opto, is a shortened form derived from the Hellenic (Greek) word, ophthalmos, meaning, "eye." Like most professions, the practice of optometry education and certification is regulated in most countries. Optometrists and optometry-related organizations interact with governmental agencies, other health care professionals, and the community to deliver eye and vision care.