Electroretinogram (ERG)

What is electroretinography?

Electroretinography is an eye exam that evaluates the retina's function by measuring tiny electrical impulses generated when light reaches it. This is done using specialised electrodes in the form of a contact lens. Electroretinography can help diagnose various causes of eye problems by detecting retinal lesions early on.

Does the exam require special preparation?

For examination, eye drops are instilled to dilate the pupils and make the surface of the eye insensitive to touch.

Is special preparation needed for the exam?

During the exam, eye drops dilate the pupils and make the eye surface less sensitive to touch.

How is electroretinography performed?

To avoid any disruptions in the electrical signals from the retina, the patient is under sedation. A special contact lens with an electrode is then put on the eye. The eye is exposed to bright stimuli of varying intensity and frequency. The electrode records the electrical nerve impulses from the retina that respond to stimuli. This recorded data is then displayed as a computer graph called an "electroretinogram".

When is electroretinography performed?

Electroretinography is commonly used to detect retinal diseases in their early stages and therapeutic control of retinal diseases and before each cataract surgery.

Common reasons for electroretinography:

• Hereditary retinal diseases
• Inflammation of the retina (retinitis)
• Sudden blindness
• Retinal lesions caused by high blood pressure
• Impaired vision
• Planning a cataract surgery

Does electroretinography have any risks or adverse effects?

The risks and complications of anaesthesia are similar to those that can occur during any surgery. Besides that, this examination is painless and without risks. The eyes are light-sensitive for a few hours due to eye drops.