Amsler Grid Test
The Amsler grid test is an ophthalmologic examination designed to detect retinal diseases, particularly macular degeneration.
General Description
The Amsler grid test is used in ophthalmology to detect ocular diseases, especially those affecting the retina. This test is characterized by the use of a 10 × 10 cm grid composed of 20 squares of 5 millimeters each, with a central fixation point. The way the patient perceives the grid determines the presence or absence of visual disturbances.
The main advantage of the Amsler grid is that it facilitates the identification of visual distortions, as these are typically easier to detect when observing geometric figures than in other visual environments.
The Amsler test evaluates the central 20 degrees of the visual field, that is, the area seen when looking straight ahead without moving the eyes laterally. If the grid lines appear distorted or wavy, if certain areas are not visible, or if a dark spot is perceived in the center, the results are considered abnormal and, therefore, indicative of ocular pathology. The conditions most commonly detected with this procedure include age-related macular degeneration (AMD), macular edema, acute macular neuroretinopathy, and serous retinopathy.
When is it indicated?
The Amsler grid test is indicated in patients presenting with symptoms of visual disturbances such as metamorphopsia (straight lines appearing wavy) or scotomas (the presence of a blind spot within the visual field).
This is the initial procedure for diagnosing AMD; however, it is not a definitive test, and more comprehensive examinations are required for confirmation.
How is it performed?
The Amsler grid test is very simple:
• The grid is placed approximately 30 cm from the patient’s eyes in a well-lit room.
• One eye is covered while the other fixates on the central point of the grid.
• The patient reports any perceived distortion (blurred, curved, or non-parallel lines, or missing areas of the grid).
• The process is repeated with the other eye.
Risks
The Amsler grid test poses no risk to the patient.
What to expect from an Amsler grid test
This ophthalmologic examination takes only a few minutes and can be performed in the office setting, without the need for hospitalization, pupillary dilation, or special medication. Once the test is completed, the patient can immediately resume normal activities.
During the test, all detected abnormalities should be reported so that the specialist can accurately assess the patient’s visual status.
It may be necessary to repeat the test periodically at home to monitor visual changes over time.
Results are obtained during the same consultation.
Specialties in which the Amsler grid test is requested
Ophthalmology specialists are responsible for performing this test.
How to prepare
No special preparation is required. Patients who wear glasses for presbyopia should perform the test while wearing them.
