What are choroid bodies?

The choroid is the layer of the vertebrate eye that lies between the retina and the sclera. It is highly vascular and contains a network of capillaries nourished by the ciliary arteries and draining via the vortex veins.

* The choroid's main function is to provide oxygen and nutrients to the outer retina.

* It also plays an important role in heat regulation and the removal of waste products from the eye.

Within the choroid, in many vertebrates, there are choroid bodies located in the tapetum lucidum.

1. Choroid bodies are cellular inclusions that are composed of a clear, rounded membrane-bound sac.

2. Inside, they are filled with a mass of loosely arranged fine granules that are either yellow, red or black in colour.

3. They contain a mixture of proteins, lipids, and carbohydrates.

4. The most common colors are silver, gold, green and red.

5. Often containing a clear central space in which there may be a few granules or pigment granules.

The choroid bodies are thought to function:

- as mechanical supports for the retina.

- to improve heat regulation.

- may also enhance vision by providing a reflecting layer that improves visual sensitivity in low light conditions.