Sesquicentennial of the ophthalmoscope.

The year 2000 coincides with the 150th anniversary of the invention of the ophthalmoscope. In 1850, Hermann von Helmholtz (1821-1894) inaugurated the modern era in ophthalmology with his magnificent instrument, which has done more to revolutionize the development of ophthalmology than any other invention or discovery. Before Helmholtz's invention, it was not possible to visualize the posterior pole of the eye in a living subject. The ophthalmoscope permitted the clinical correlation of signs and symptoms with findings in the retina, vitreous, and optic nerve. The ophthalmoscope became the model for all forms of endoscopy that followed. It is often compared in importance with 2 earlier inventions, the telescope (17th century) and the stethoscope (early 19th century). All of these instruments made dramatic new information available to the human mind.