Stargardt Disease: Symptoms & Treatments

Stargardt disease is a macular degeneration condition that affects the macula, which is basically located in the center of the retina. The macula’s cone receptor cells provide us with color and central vision, which is required for reading. The symptoms will normally appear at the early age of twenty and is very a progressive eye disease that will end with color blindness. It affects more than twenty-five thousand Americans, but the actual totals are not known.

 

Eye

 

Cornea is the transparent dome that covers the iris. It reflects light and provides focus power.

Iris is the pigment portion of the eye and is responsible for adjusting the pupil size.

Pupil allows light to hit the retina

Sclera is the white, external portion of the eye ball

Conjunctiva is the transparent membrane that covers the sclera

Retina contains rods and cones, which are photoreceptors. It is a layer that is light sensitive and found at the back of the inner eye

Rod cells control vision in low light

Cone cells control vision and detail. They are found in the fovea (tiny pit), which provides the sharpest vision and located in the macula

Optic nerve sends visual data to the brain from the retina

 

Etiology

 

Stargardt disease is an autosomal recessive disorder and involves the ABC 1 gene. The ABCA4 is potentially responsible for this disease and both parents must carry the gene, in order for the child to have a 25% chance of developing the disease.

ABCA4 gene produces an abnormal protein, which interferes in the transport of energy to the photoreceptors causing them to degenerate. Lipofuscin (lipid rich wastes) build up in the layer that separates the photoreceptors.

 

Signs & Symptoms

 

Early Symptoms include gray spots, reading difficulty, and the inability to adapt the vision between bright and dark environments

Partial color blindness

Blind spot in central vision

 

Diagnosis

 

Electroretinography involves the placement of electrodes on the cornea to measure electrical response

Gluorescein Angiography checks blood flow in the retina. A fluorescent dye is used for the test

Electrooculography records eye movement eye position

 

Treatment

 

There is no current cure for Stargardt disease, because studies and clinical trials have been ongoing since 2010.