Ophthalmology
Ophthalmology is the medical and surgical specialty focused on the eyes and visual system, including vision, eye disease, screening, diagnosis, imaging, medicines, laser care, surgery, and prevention of vision loss.
What ophthalmology is
Ophthalmology is the branch of medicine and surgery focused on the eyes and visual system. Ophthalmologists diagnose eye disease, prescribe medical treatment, perform eye surgery, manage injuries, monitor chronic conditions, and help prevent vision loss. The field overlaps with neurology, endocrinology, rheumatology, pediatrics, geriatrics, emergency care, and public health.
How vision works
Vision begins when light enters the eye through the cornea and lens, which focus images onto the retina. Retinal cells convert light into nerve signals that travel through the optic nerve to the brain. Clear vision depends on the cornea, lens, eye pressure, retina, optic nerve, blood vessels, tear film, eye muscles, and brain working together.
Eye exams and first clues
An eye exam can reveal more than whether someone needs glasses. Clinicians may check visual acuity, pupils, eye movement, eye pressure, eyelids, cornea, lens, retina, optic nerve, and visual fields. Blurry vision, eye pain, redness, flashes, floaters, double vision, sudden vision loss, or a curtain-like shadow can point to different levels of urgency.
Imaging and diagnosis
Ophthalmology uses close examination and specialized imaging. A slit lamp magnifies the front of the eye. A dilated exam lets clinicians see the retina and optic nerve. Optical coherence tomography, or OCT, creates detailed cross-sectional images of retinal structures. Visual field testing can detect side-vision loss. Ultrasound, fluorescein angiography, photography, and other tests help answer specific questions.
Conditions it covers
Ophthalmology covers cataracts, glaucoma, retinal disease, diabetic retinopathy, age-related macular degeneration, corneal disease, uveitis, dry eye, eye infections, eyelid disorders, eye trauma, amblyopia, strabismus, refractive error, optic nerve disease, tumors, and complications of systemic illnesses. Some conditions are painless but still threaten sight, which is why screening can matter.
Treatment and surgery
Treatment may include glasses, contact lenses, eye drops, oral or injected medicines, laser treatment, office procedures, or surgery. Cataract surgery replaces a cloudy lens with an artificial lens. Glaucoma treatment lowers eye pressure to protect the optic nerve. Retinal treatments may use injections, lasers, or surgery. The best plan depends on diagnosis, severity, risks, and the patient's goals.
Prevention and public health
Many causes of vision loss can be delayed, treated, or prevented when found early. Diabetes eye exams can detect retinopathy before symptoms appear. Glaucoma screening is important for people at higher risk because damage may be silent at first. Eye protection can reduce injuries. Public health work also addresses access to exams, cataract surgery, childhood vision problems, infection prevention, and avoidable blindness.
Why it matters
Vision affects reading, work, movement, driving, learning, independence, social connection, and safety. Eye disease can also reveal diabetes, high blood pressure, inflammatory disease, infection, neurologic disease, or medication toxicity. Ophthalmology matters because timely care can preserve sight, relieve pain, detect systemic disease, and help people adapt when vision cannot be fully restored.