Electroretinography with interpretation and report
CPT4 code
Name of the Procedure:
Electroretinography (ERG)
Summary
Electroretinography (ERG) is a diagnostic test that measures the electrical activity of the retina, the light-sensitive layer at the back of the eye. This helps doctors evaluate how the retina is functioning.
Purpose
ERG is used to diagnose and monitor various eye conditions, such as retinal dystrophies, diabetic retinopathy, and other disorders affecting the retina. The goal is to detect abnormalities in retinal function to guide treatment decisions.
Indications
Specific symptoms or conditions that may warrant an ERG include:
- Unexplained vision loss
- Night blindness
- Retinal degeneration
- Family history of inherited retinal diseases
Patient criteria:
- Presence of symptoms suggesting retinal dysfunction
- Routine monitoring for those diagnosed with retinal conditions
Preparation
- Patients may be instructed to avoid caffeine and certain medications before the test.
- Contact lenses should be removed.
- Pupils may be dilated using special eye drops for better results.
- No fasting is required.
Procedure Description
- The patient is seated comfortably in a darkened room.
- Special eye drops are applied to numb and dilate the eyes.
- A small electrode is placed on the surface of the eye or on the skin near the eye.
- The patient is then asked to look at flashing lights or patterns while the electrical responses of the retina are recorded through the electrode.
- Multiple tests may be conducted to measure responses under different lighting conditions.
Tools and equipment:
- ERG machine
- Electrodes
- Eye drops for numbing and dilation
Anesthesia:
- Local anesthetic eye drops to numb the eye
Duration
The procedure typically takes about 30 to 60 minutes.
Setting
ERG is usually performed in an ophthalmologist's office or a specialized outpatient clinic.
Personnel
- Ophthalmologist or a trained technician
Risks and Complications
- Mild discomfort or irritation due to the electrode or eye drops
- Rarely, a temporary increase in eye pressure
Benefits
- Provides crucial information about retinal function
- Helps in early diagnosis of retinal disorders
- Guides treatment plans and monitoring of retinal diseases Expected benefits are usually realized immediately upon interpretation of the results.
Recovery
- Most patients can resume normal activities immediately.
- Temporary blurred vision from dilating drops usually resolves within a few hours.
- Follow-up appointments may be scheduled based on the results.
Alternatives
Other diagnostic options may include:
- Visual field tests
- Optical coherence tomography (OCT)
- Fundus photography Pros and cons:
- ERG provides direct measurement of retinal function, which other tests may not offer.
- Other imaging tests may be non-invasive and quicker but may not give as detailed a functional analysis.
Patient Experience
During the procedure, patients might experience:
- Mild discomfort from the electrode and eye drops
- Sensitivity to light due to pupil dilation After the procedure:
- Temporary blurred vision
- Mild eye irritation, which usually resolves quickly Pain management:
- The procedure is generally painless due to the numbing effect of the eye drops.