Wentworth-Douglass Hospital
(603) 742-5252
Decrease (-) Restore Default Increase (+) font size
Physicians
Site Search

Contact lens electrode on eye
Contact lens electrode on eye


Definition:

Electroretinography is a test to measure the electrical response of the eye's light-sensitive cells, called rods and cones.



Alternative Names:

ERG



How the test is performed:

While you are comfortably seated in a chair, the health care provider places numbing drops into your eyes, so you do not feel pain during the test. Your eyes are then propped open and an electrical sensor (electrode) is placed on each eye.

The electrode measures the electrical activity of the retina in response to light. A light flashes, and the electrical response travels from the electrode to a TV-like screen, where it can be viewed and recorded. The normal response pattern has waves called A and B.

The doctor will take the readings in normal room light and then again in the dark, after allowing 20 minutes for your eyes to adjust.



How to prepare for the test:

No special preparation is necessary for this test.



How the test will feel:

The probes that rest on your eye may feel like an eyelash. The test takes about one hour to perform.



Why the test is performed:

This test is done to detect disorders of the retina. It is also useful in determining if retinal surgery is recommended.



Normal Values:

Normal test results will show a normal A and B pattern in response to each flash.



What abnormal results mean:

The following conditions may cause abnormal results:



What the risks are:

The cornea may get a superficial scratch from the electrode. Otherwise, there are no risks associated with this procedure.



Special considerations:

You should not rub your eyes for an hour after the test, as this could injure the cornea. Your doctor will discuss with you the results of the test and what it means for you.




Review Date: 8/22/2008
Reviewed By: Paul B. Griggs, MD, Department of Ophthalmology, Virginia Mason Medical Center, Seattle, WA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
adam.com


Find What You Need

Events
Careers
Foundation
About Us
Contact
Directions
News
Social Media Agreement
Joint Notice
Web Privacy Policy
WDH Staff Portal

Centers & Services

Cancer Center
Cardiovascular Care
Joint Replacement
Women & Children's
Physician Offices
Other Services

Conditions & Treatments

Health Information
Ebola Information

Support Services

Support Groups
Care-Van
Dental Center
Social Work
Food & Nutrition
Integrative Wellness
Spiritual Care
Concerns & Grievances
Homecare and Hospice

For Patients

Pay Your Bill Online
Pricing Estimates
Financial Assistance
Interpreter Services
Surgery Preparation
Medical Record Request
Advance Directives
Clinical Research & Trials

For Healthcare Professionals

Work and Life
Financial Well-Being
Career and Growth

The Wentworth-Douglass Health System includes:

 

Address

Wentworth-Douglass Hospital
789 Central Avenue, Dover, NH 03820
Phone: (603) 742-5252
Toll free: 1 (877) 201-7100