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

lens A lens is a transmissive optical device which 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 (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...

optic disc The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye. The ganglion cell axons form the ...

macula The macula (/ˈmakjʊlə/) or macula lutea is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around and is subdivided into the umbo, foveola, foveal av ...

fovea Fovea () (Latin for "pit"; plural foveae ) is a term in anatomy. It refers to a pit or depression in a structure. Human anatomy *Fovea centralis of the retina * Fovea buccalis or Dimple * Fovea of the femoral head * Trochlear fovea of the fr ...

, and

posterior pole In ophthalmology, the posterior pole is the back of the eye, usually referring to the retina between the optic disc and the macula.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. ...

.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. The fundus can be examined by

ophthalmoscopy Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an eye examination and may be done as part ...

and/or

fundus photography Fundus photography involves photographing the rear of an eye, also known as the fundus. Specialized fundus cameras consisting of an intricate microscope attached to a flash enabled camera are used in fundus photography. The main structures that ...

Variation

The color of the fundus varies both between and within species. In one studyFree full text in PubMed Central
/ref> of

primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...

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 sign Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

s 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, vag ...

s, exudates,

cotton wool spots Cotton wool spots are opaque fluffy white patches on the retina of the eye that are considered an abnormal finding during a funduscopic exam (also called an ophthalmoscopic exam). Cotton wool spots are typically a sign of another disease state, mo ...

blood vessel The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...

abnormalities (

tortuosity Tortuosity is widely used as a critical parameter to predict transport properties of porous media, such as rocks and soils. But unlike other standard microstructural properties, the concept of tortuosity is vague with multiple definitions and vari ...

pulsation A pulse, in physiology, is the throbbing of arteries resulting from heartbeat. Pulse, The Pulse or Pulses may also refer to: Botany * Pulse (legume), any agriculturally significant annual leguminous food crop, such as peas, beans, lentils, and ...

and new vessels) and

pigmentation A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compo ...

.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 Hypertensive retinopathy is damage to the retina and retinal circulation due to high blood pressure (i.e. hypertension). Signs and symptoms Most patients with hypertensive retinopathy have no symptoms. However, some may report decreased or blurr ...

. The eye's fundus is the only part of the human body where the

microcirculation The microcirculation is the circulation of the blood in the smallest blood vessels, the microvessels of the microvasculature present within organ tissues. The microvessels include terminal arterioles, metarterioles, capillaries, and venules. ...

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

{{Eye Human eye anatomy

Variation

Clinical significance

See also

References