Download Optometry 3 – Visual Fields

Advanced Optometric Procedures Lab
Visual Fields -- Amsler Grid
Yaron Ashendorf MSc, Moptom
Student Name: _______________________
Date Due: __________
Procedure:
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The patient should wear his usual near correction.
Bright illumination (room and overhead) should be used.
Test only one eye at a time.
The test charts are held at a distance of 30 cm from the patient.
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Occlude the left eye, while testing the right eye. (If necessary, test the better seeing eye first.)
Instruct the patient to look at the center dot. Ask if the patient can see the dot. The patient must continue to fixate
at the center dot throughout the test.
Instruct the patient not to move his eyes, but to “notice” features of the grid pattern.
“Can you see the four corners?”
“Are any of the lines missing parts?” “Do any lines have holes in them?” If so, where?
“Are all of the lines straight?” “Are any lines wavy?” If so, where?
“Are all the little squares the same size?” “Which squares look larger?”
Watch the patient’s eye during the test. Make sure that the eye does not move and continues to fixate at the
center dot.
Record the results as “Within Normal Limits” (WNL) if no problems are reported.
Record defects in the visual field on a sample grid, and label the defect (e.g. “scotoma”, “wavy” – barrel or
pincushion distortion). You may ask the patient to draw what he/she sees on the sample grid. (Label the defect.)
Repeat the above to test the left eye (right eye occluded).
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Lab Exercise:
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Perform the Amsler Grid test for each eye on 2 “patients” (students) in class.
Record your results.
Using the “special” glasses placed over the patient’s near correction perform the Amsler Grid test for your 3rd
patient. (You may use one of the “normal” patients that you tested before for the test with the “special” glasses.)
Record your results (including the number on the “special” glasses).
Answer the questions from the bottom of this page. Use the back of this paper for your answers.
Results: (Attach a separate sheet with a map of the defects, if defects are found)
Patient #1: __________________
OD _____________
OS _____________
Date:________
Patient #2: __________________
OD _____________
OS _____________
Date:________
Patient #3 (Special Glasses): ______________ OD _____________
OS _____________
Date:________
Questions: (Write your short answers on the back of this page.)
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Name 2 ocular diseases that this test would help to diagnose and treat?
Why is the blindspot not noticed as a scotoma in this test?
Revised JB 11/11