Keystone 1157 instruction manual Horizontal Field Testing, 85 70 55 Nasal, 55 70

Horizontal Field Testing

HORIZONTAL FIELD
LEFT SIDE		RIGHT SIDE
85° 70° 55° NASAL	NASAL	55° 70° 85°

This test shows a subject's range of vision to each side when he/she looks straight ahead. Having the subject direct his/her attention to a far-point stereo target and then lighting the peripheral target lamps at random. The stereo target used should be a simple binocular target.

Tell the subject to continue looking at the numbered circles of the color vision target. Explain that at any time a light may flash to the left or right side of the target. When it does, the subject is to indicate "left side", "right side", or "both sides."

All peripheral target lamps should be lit, but the order of their appearance is left to the examiner. Checking the appropriate box on the form for each target identified.

Subjects should be able to respond to at least the 55° and 70° temporal tests for each eye. If they cannot, a visual problem may exist and referral should be made.

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