Vision Test for Alport Syndrome Diagnosis

Alport syndrome is a genetic condition that is known to cause kidney disease, hearing loss, and certain eye abnormalities. The disease is characterized by the body’s inability to produce functional type IV collagen, an important structural protein.

The inefficient production of type IV collagen can affect many parts of the eye, including the cornea, lens capsule, and retina.

In addition to a general vision exam, several more specific eye examinations are important in the diagnosis of Alport syndrome and to monitor disease progression after diagnosis. If Alport syndrome is suspected, it is best to work with an ophthalmologist who is familiar with the disease. The tests required to assess Alport patients are widely available, inexpensive, and noninvasive.

Slit-lamp examination

Corneal abnormalities can be identified using a slit-lamp examination. This technique requires the use of a microscope called a slit lamp, which the ophthalmologist focuses on the front of the patient’s eye. The slit lamp magnifies the eye while maintaining 3-D viewing capabilities. This allows the ophthalmologist to detect any abnormalities on the cornea, including recurrent corneal abrasion, a potential symptom of Alport syndrome.

Retinoscopy and retinal photography

Anterior lenticonus is a change in the shape of the lens of the eye where one or both lenses extend outward to form a conical shape. Approximately 15 to 20 percent of Alport syndrome patients are affected by anterior lenticonus. A retinoscope is fairly similar to an ophthalmoscope, but the light source differs slightly, making it more effective to view the retina and to identify anterior lenticonus.

Dot-and-fleck retinopathy is the most common ocular symptom of Alport syndrome, affecting about 85 percent of male patients. Dot-and-fleck refers to the white or yellow dots that appear in the retina as Alport syndrome progresses. This symptom can be observed by taking a digital picture of the back of the eye, a procedure known as retinal photography. Retinal photographs of the central and outer parts of the retina will typically be collected and analyzed to look for any retinopathy, such as dot-and-fleck and macular holes. Macular holes usually require additional observation using optical coherence tomography (OCT).

Optical coherence tomography

Premature macular holes develop in fewer than 5 percent of Alport syndrome patients. A macular hole is a tear in the eye at the level of the retina through which ocular fluids can escape. This can potentially cause blurred and distorted vision. It is more common in the elderly population, but Alport syndrome patients have been seen to develop them at an earlier age.

Macular holes can be identified using OCT. This noninvasive medical imaging technique is capable of collecting two- and three-dimensional images of the eye. It works by shining infrared light into the eye and collecting the light that is reflected. This method is similar to an ultrasound, except that light is used as the medium instead of sound.

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Alport Syndrome News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.