The fundus of the eye is the interior surface of the eye opposite the

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

and includes the

retina The retina (; or retinas) is the innermost, photosensitivity, light-sensitive layer of tissue (biology), tissue of the eye of most vertebrates and some Mollusca, molluscs. The optics of the eye create a focus (optics), focused two-dimensional ...

, optic disc, macula, fovea, and posterior pole.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. The fundus can be examined by ophthalmoscopy and/or fundus photography.

Variation

The color of the fundus varies both between and within species. In one studyFree full text in PubMed Central
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primate Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers a ...

s the retina is blue, green, yellow, orange, and red; only the human fundus (from a lightly pigmented blond person) is red. The major differences noted among the "higher" primate species were size and regularity of the border of macular area, size and shape of the optic disc, apparent 'texturing' of retina, and pigmentation of retina.

Clinical significance

Medical signs that can be detected from observation of eye fundus (generally by funduscopy) include

hemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, ...

s, exudates, cotton wool spots,

blood vessel Blood vessels are the tubular structures of a circulatory system that transport blood throughout many Animal, animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the Tissue (biology), tissues of a Body (bi ...

abnormalities ( tortuosity, pulsation and new vessels) and pigmentation.Imran Akram, Adrian Rubinstein "Common retinal signs. An overview", "Optometry Today", 28/01/05

Arteriolar constriction, seen as "silver wiring", and vascular tortuosities are seen in hypertensive retinopathy. The eye's fundus is the only part of the human body where the microcirculation can be observed directly.Ronald Pitts Crick, Peng Tee Khaw, ''A Textbook of Clinical Ophthalmology: A Practical Guide to Disorders of the Eyes and Their Management'', 3rd edition, World Scientific, 2003, The diameter of the

s around the optic disc is about 150 μm, and an ophthalmoscope allows observation of blood vessels with diameters as small as 10 μm.

References

{{Authority control Human eye anatomy

Variation

Clinical significance

See also

References