Patient Correction; Patient Seating And Position - Zeiss Humphrey matrix User Manual

PATIENT CORRECTION

For accurate visual field test results, correct the patient to within the refractive error cited in the
table below. Use the patient's habitual correction or a trial frame if needed. It is OK to use
bi-focal or progressive lenses.
N-30-5 (-1) FDT Screening
N-30-F FDT Threshold
24-2-5 (-1) FDT Screening
24-2 FDT Threshold
30-2 FDT Threshold
Macula FDT Threshold
10-2 FDT Threshold
Use a trial frame instead of the patient's habitual correction if:
• Corrective lenses are tinted or photo-chromatic
• Small or thick eye glass frames obscure part of the testing field
Verify that the patient's eyes are undilated during the visual field test, unless his or her pupil is
less than 3 mm.

PATIENT SEATING AND POSITION

• Confirm the Patient Visor is in the correct position so that the Patient Eyepiece is aligned
with the tested eye.
• Check that the patient is relaxed and holding the Response Button properly.
• Adjust the position of the patient or the instrument to obtain proper, comfortable
patient alignment. Proper alignment requires the patient to see all four self-alignment
points at the same time while fixating on the black square target in the center. It is OK if the
fixation target appears fuzzy to the patient.
Align the patient's head against the forehead rest by adjusting the table or seat height for
proper, comfortable head position relative to the instrument. Slide the instrument towards
the patient if needed.
• When Eye Monitoring is turned on, an image of the patient's eye is displayed on the Testing
screen. Keep the patient's pupil inside the circle on the video image throughout the test.
Keeping the pupil perfectly centered for proper alignment is not necessary, but it should stay
within the circle.
A very important factor affecting test reliability is the steadiness of the patient fixation.
Unless the tested eye accurately fixates on the target while responding to stimuli, there is
a possibility of unreliable results.
A comfortable patient position with good fixation is more important than obtaining or
keeping exactly centered alignment.
24
Tests Patient Corrected within:
+/- 6 Diopters
+/- 3 Diopters
+/- 2 Diopters
Humphrey Matrix Visual Field Instrument
Rev. D 08/21/06 PN 701692