Posterior segment

Posterior Segment

The posterior segment or posterior cavity is the back third of the eye that includes the anterior hyaloid membrane and all of the optical structures behind it: the vitreous humor, retina, choroid, and optic nerve.

Anatomy

The posterior segment is bounded anteriorly by the posterior surface of the lens and the Zonule of Zinn, and posteriorly by the retina. It contains the vitreous humor, a clear gel that fills the space between the lens and the retina. The posterior segment also contains the macula, a specialized area of the retina responsible for central vision, and the optic disc, where the optic nerve exits the eye.

Function

The primary function of the posterior segment is to transmit light from the lens to the retina. The vitreous humor helps to maintain the shape of the eye and provides a clear path for light to reach the retina. The retina then converts the light into electrical signals that are sent to the brain via the optic nerve.

Diseases and Disorders

There are several diseases and disorders that can affect the posterior segment, including retinal detachment, macular degeneration, diabetic retinopathy, and glaucoma. These conditions can lead to vision loss if not properly diagnosed and treated.

Treatment

Treatment for diseases and disorders of the posterior segment depends on the specific condition. Options may include medication, laser therapy, or surgery. In some cases, treatment can restore lost vision, while in others it may only prevent further vision loss.

See Also

• Anterior segment
• Eye examination
• Ophthalmology