Fundus photography

The main structures that can be visualized on a fundus photo are the central and peripheral retina, optic disc and macula.

In 1851, Hermann von Helmholtz introduced the Ophthalmoscope, and James Clerk Maxwell presented a colour photography method in 1861.

Early fundus photos were limited by insufficient light, long exposures, eye movement, and prominent corneal reflexes that reduced the clarity detail.

Lucien Howe, a well-known name in Ophthalmology, and his assistant, Elmer Starr, collaborated on the fundus photography project in 1886–88.

Hundreds of specialists worked to overcome the problem, which was finally achieved in the early 20th century by Friedrich Dimmer, who published his photographs in 1921.

These improvements have helped make modern fundus photography a standard ophthalmic practice for documenting retinal disease.

[10] The optics of a fundus camera are similar to those of an indirect ophthalmoscope in that the observation and illumination systems follow dissimilar paths.

When the button is pressed to take a picture, a mirror interrupts the path of the illumination system allow the light from the flash bulb to pass into the eye.

Simultaneously, a mirror falls in front of the observation telescope, which redirects the light onto the capturing medium, whether it is film or a digital CCD.

Because of the eye's tendency to accommodate while looking through a telescope, it is imperative that the exiting vergence is parallel in order for an in-focus image to be formed on the capturing medium.

[22] The medical necessity of fundus photography must be recorded comprehensively so that the clinician is able to compare photographs of a patient from different timelines.

The interpretation of fundus photographs that are glaucomatous must contain a description of the vertical and horizontal cup to disc ratio, vessel pattern, diffuse or focal pallor, asymmetry and development of the above factors.