Medical specialty dealing with the eyes, dating to 1805. Frans C. Donders's 1864 advances in optics allowed eyeglasses to be fitted to vision problems. The ophthalmoscope made it possible to look inside the eye and relate eye defects to internal conditions. More recent advances include eye exams, early treatment of congenital defects, and eye banks to store corneas for transplants. Ophthalmologists test visual function and examine the eye for faulty development, disease, injury, degeneration, aging, or refractive errors. They prescribe treatment for eye disease and lenses for refraction and perform surgery when needed. See alsooptometry, visual-field defect.