What are the other Names for this Condition? (Also known as/Synonyms)

• DCA (Diffuse Choroidal Atrophy)

What is Diffuse Choroidal Atrophy? (Definition/Background Information)

• Diffuse Choroidal Atrophy (DCA) is an inherited autosomal dominant disorder that affects the choroid and retina, which are parts of the eye. It is classified as a type of choroidal dystrophy
• The condition is similar to central areolar choroidal dystrophy, although manifestation of signs and symptoms in the affected individuals occur a decade earlier
• Even though Diffuse Choroidal Atrophy is a congenital condition, the onset of signs and symptoms generally occur during young adulthood. The condition is progressive in nature and can lead to total blindness
• The genetic mutation causing Diffuse Choroidal Atrophy is not identified yet. Since, the condition is inherited, a positive family history is a key risk factor
• Diffuse Choroidal Atrophy results in signs and symptoms that include night vision difficulties and loss of both central and peripheral vision. The condition is progressive and ultimately results in total vision impairment
• A healthcare provider can use various physical (eye) exams, blood tests, and imaging studies to diagnose Diffuse Choroidal Atrophy. Currently, there is no treatment available to manage the condition and the prognosis of DCA is typically poor

Who gets Diffuse Choroidal Atrophy? (Age and Sex Distribution)

• Diffuse Choroidal Atrophy is a congenital condition that is manifested at birth. However, the onset of the signs and symptoms occur in the ages between 20-40 years, which is about 10 years earlier than that for central areolar choroidal dystrophy (CACD)
• The condition affects both males and females
• Individuals of different racial and ethnic backgrounds can be affected

What are the Risk Factors for Diffuse Choroidal Atrophy? (Predisposing Factors)

• The main risk factor for Diffuse Choroidal Atrophy is a positive family history
• High myopia or shortsightedness

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one's chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Diffuse Choroidal Atrophy? (Etiology)

• Diffuse Choroidal Atrophy is a congenital disorder that is inherited in an autosomal dominant manner
• It is classified as a type of choroidal dystrophy and affects both the choroid and retinal pigment epithelium (RPE)
• The gene causing the condition remains unidentified

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition or pass it on to their offspring.

What are the Signs and Symptoms of Diffuse Choroidal Atrophy?

The signs and symptoms of Diffuse Choroidal Atrophy are observed in young and middle-aged adults. It may vary from one individual to another and is progressive in nature. The signs and symptoms may include:

• Difficulty in night vision or dim-light vision (nyctalopia)
• Loss of both central and peripheral vision
• Gradual loss of vision
• The condition affects both the eyes (bilateral presentation)

The signs and symptoms of some individuals progress more rapidly than the others. The involvement of the macula seems to advance the progression of the condition.

How is Diffuse Choroidal Atrophy Diagnosed?

A healthcare professional may diagnose Diffuse Choroidal Atrophy using the following tests and procedures:

• Physical examination and analysis of previous medical history
• Eye examination by an eye specialist
• Fundoscopic (ophthalmoscopic) examination by an eye specialist, who examines the back part of the eye (or the fundus)
• Visual acuity test using a special and standardized test chart (Snellen chart)
• Slit-lamp examination: Examination of the eye structure using a special instrument called a slit-lamp. In this procedure, the pupils are dilated and the internal eye structure is examined
• Tonometry: Measurement of intraocular pressure or eye fluid pressure, especially to detect conditions such as glaucoma
• Fundus fluorescein angiography (FFA): In this technique, the eye blood vessels are examined using a fluorescein dye
• Fundus autofluorescence (FAF) imaging: It is a diagnostic technique to examine the fundus of the eye using a fluorescent dye
• Indocyanine green (ICG) angiography: It is used to examine the blood vessels of the choroid using a dye, called indocyanine green, particularly to study the choroid
• B-scan ultrasonography: Special ultrasound scan of the eye through a non-invasive diagnostic tool, to assess health of the eye structures
• Electroretinogram (ERG): It is a technique to measure electrical activities in the retinal cells
• Optical coherence tomography (OCT) of eye: Radiological imaging technique to visualize the eye structure
• Blood tests that include:
  • Complete blood count (CBC) with differential
  • Erythrocyte sedimentation rate (ESR)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Diffuse Choroidal Atrophy?

The complications of Diffuse Choroidal Atrophy may include:

• Retinal detachment: An eye condition wherein the retina gets separated from the eye structures that holds the retinal layers together
• Total blindness due to progression of the condition

How is Diffuse Choroidal Atrophy Treated?

• Currently, there is no definitive treatment modality available for Diffuse Choroidal Atrophy
• Symptomatic treatment to address the signs and symptoms may be employed by the healthcare provider
• Rehabilitation, vocational, or occupational therapy may be provided to the affected individuals with vision loss

The healthcare provider may recommend the best treatment options based upon each individual’s specific circumstances.

How can Diffuse Choroidal Atrophy be Prevented?

• Currently, there are no specific methods or guidelines to prevent Diffuse Choroidal Atrophy, since it is a genetic condition
• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders such as Diffuse Choroidal Atrophy

What is the Prognosis of Diffuse Choroidal Atrophy? (Outcomes/Resolutions)

The prognosis of Diffuse Choroidal Atrophy is poor and the condition invariably leads to complete vision loss.

Additional and Relevant Useful Information for Diffuse Choroidal Atrophy:

Please visit our Eye & Vision Health Center for more physician-approved health information:

http://www.dovemed.com/health-topics/vision-center/