PEDIATRIC RETINAL DISEASES

INTRODUCTION: WHAT IS THE RETINA?

In many ways the eye is like a camera. The light passes through the transparent lens to display an image in back wall of the eye. This wall, called the retina, is an thin layer of tissue filled with many different types of cells. The most commonly known cells are the light-sensitive cells called rods and cones. The cones are responsible for detailed color vision, while the rods allow you to see shades of gray. 

After the activation of the nerve and light-sensitive cells, the information is then sent in form of electrical signal to the brain through the optic nerve, i.e. the collection of all the nerve fibers from the retina. After the signals are received in the back part of the brain (the occipital lobe), the brain processes the information and gives us the ability to perceive the world around us through the sense of eyesight.

The eye is of course a very complex organ and understandably any changes to the retina tissue or supporting tissue and cells, such as the blood vessels that provide nourishment, are vulnerable to changes. Although retinal diseases wary widely, most will over time cause visual impairment. Some of the most common retinal diseases and conditions include:

• Retinal tears

• Retinal detachment

• Epiretinal membrane

• Macular hole

• Macular degeneration

• Diabetic retinopathy

• Inherited retinal disease

Although the majority of retinal disease occurs in adulthood, there is a number of disease processes that affect children, even from the first days of their life. Some of the most common of these diseases are Retinopathy of prematurity (ROP), Coats disease and Familial Exudative Vitreoretinopathy (FEVR).

Read more below to learn more about pediatric retinal diseases.

COATS DISEASE

Coats is a rare progressive eye disorder that is characterized by abnormal blood vessel in the outer part of the retina. The affliction causes the small blood vessels to leak fluid or blood under, inside or above the retina. As the fluid builds up, the retina swells until it finally detaches from the wall of the eye. Left untreated, the retinal detachment results in loss of vision and eventually blindness. 

It is a disease that affects mostly young males (by a male:female ratio of 3:1). Most are diagnosed between the ages of 4 to 6 years, although up to a third are diagnosed after the age of 30 when symptoms start. Per date, the exact cause of Coats disease remains unknown, with some genes implicated in selected cases. 

Coats disease can be divided into 5 stages of disease progression. In general, the earlier the disease is diagnosed and the correct treatment initiated, the better the outcome will be. Regular check-ups and treatments by an expert in pediatric retina will help maintain good vision.

Coats disease when not treated can cause severe complications, such as cataract (clouding of the lens) and intractable glaucoma (elevated eye pressure), and can end up in some cases in a blind and painful eye that needs to be removed.

Symptoms of Coats disease include in younger children: 

• Abnormal white or yellow light reflected from the pupils (often spotted in pictures taken with flash – “leukocoria”)

• Strabismus (misalignment of the eyes - usually with an outward crossing eye)

• Decreased or blurry vision

• Redness or eye pain

Older children or adults can also notice: 

• Decreased depth perception

• Loss of peripheral vision

• Seeing floaters, spots or “flies”

• Seeing double

• Trouble seeing at night

• Change in the color of the iris 

How is it diagnosed?

To check the health of the retina (the back-segment of the eye) and look for any changes to the blood vessels, the retinal specialist will perform a dilated eye exam using drops that widen the pupil. The doctor will also check the rest of the eye to control for other eye conditions. The doctor might also use other non-invasive imaging techniques such as ultrasound of the eye and optical coherence tomography (OCT). Based on the results the doctor can assess which stage the disease is at and administer the appropriate treatment. In case of children that cannot be fully examined at the office, an examination under anesthesia (EUA) will be proposed.

Treatment can include: 

• Laser treatment (aimed at constricting the abnormal blood vessels and stopping fluid leaks) – the mainstay of treatment for Coats disease

• Anti-VEGF injection therapy (anti-vascular endothelial growth factor medication given by direct injection to the eye to reduce fluid leaks) – an adjunct to laser treatment

• Surgery (to remove excessive fluid detaching the retina, as well as scar tissue preventing the retina from reattaching to the eye wall)

• Glasses and eye patches (in the pediatric age group in order to treat amblyopia/lazy eye)