Choroidal dystrophies

External and internal eye anatomy

The cornea allows light to enter the eye. As light passes through the eye the iris changes shape by expanding and letting more light through or constricting and letting less light through to change pupil size. The lens then changes shape to allow the accurate focusing of light on the retina. Light excites photoreceptors that eventually, through a chemical process, transmit nerve signals through the optic nerve to the brain. The brain processes these nerve impulses into sight.

Definition

Choroidal dystrophy is an eye disorder involving the choroid, a layer of blood vessels between the sclera and retina.

Causes, incidence, and risk factors

Choroidal dystrophies are usually due to an abnormal gene (hereditary). It usually affects males, starting in childhood.

Symptoms

The first symptoms are peripheral vision loss and vision loss at night.

Signs and tests

An eye surgeon who specializes in the back of the eye (retina specialist) diagnoses choroidal dystrophies. The following tests may be needed to diagnose the condition:

Treatment

Choroidal dystrophies are usually treated with observation.

References

Grover S, Fishman GA. Choroidal dystrophies. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier; 2008:chap 6.

See also:

  • Special Topic

    Choroid

    Eye

    The choroid is the layer of blood vessels and connective tissue between the (white of the eye) and . It is part of the and supplies nutrients to the inner parts of the eye. Inflammation of the choroid is called .

  • Special Topic

    Retina

    Eye

    The retina is the light-sensitive layer of tissue at the back of the inner eye. It acts like the film in a camera — images come through the eye’s lens and are focused on the retina. The retina then converts these images to electric signals and sends them via the optic nerve to the ...

  • Special Topic

    Sclera

    Eye

    The sclera is the white outer wall of the eye. It is a tough, fibrous tissue that extends from the cornea (the clear front section of the eye) to the optic nerve at the back of the eye. The sclera gives the eye its white color.

Review date:
October 27, 2009
Reviewed by:
Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Copyright Information A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.