the goldman vf is a manual perimeter. the goldmann perimeter is capable of both static and kinetic...
TRANSCRIPT
The Goldman VF is a manual perimeter.
The Goldmann perimeter is capable of both static and kinetic perimetry.
Isopters are used to show VF areas of equal or greater sensitivity.
Each isopter represents a different stimulus size that was presented to the patient and is marked by the tech to show the boundaries of the stimulus size.
Apostilbs (Asb) An expression of
light intensity used while performing the Goldmann perimeter.
Basically- How bright the stimulus (light) is!
The higher the number, the brighter the stimulus (light).
Decibels (dB) An expression of
light intensity used while performing a computerized VF.
The smaller the number, the brighter the target is.
Brightness of stimulus controlled by numeric lever.
0,1,2,3,4. 0 is dimmest 4 is brightest
Brightness of stimulus also controlled by alphabetic lever.
a,b,c,d,e. a is dimmest e is brightest
Stimulus Size
You can also change the size of the stimulus. There are 6 sizes.
0 I II III IV V
“O” is the smallest size and is rarely used. “ V “ is the largest size and can be used for patient’s
with very limited VA. The size of the stimulus is measured in mm. 1/64mm, ¼mm, 1mm, 4mm, 16mm, and 64mm. Changing the stimulus size lever 1 position makes
the stimulus 4 times larger.
Fixation must be monitored. Selection of stimulus size, intensity and
brightness. Moving the stimulus (manually). Recording the patient responses and
labeling all isopters with color coding or Stimulus size and brightness.
Example V 4 e or I 2 e largest smallest
It is very important to explain what the patient should expect.
Make it clear the test will not be accurate if the patient does not look at the fixation target at all times. If they do deviate, redirect them.
Explain why you are doing the test. Explain where the “lights” will be and to press
down and release the button every time they see a light.
Let them know how small the “lights” will be. Remember- You are the technician, it is your
responsibility to inform the patient so an accurate test can be performed while the patient feels comfortable enough to do it!!!
Static and kinetic testing Change the size and intensity during the
test according to patient responses. You are moving the target according to
the patient’s responses. More skill and practice are needed to
perform an accurate test within a reasonable amount of time.
Now try to perform a Goldmann field on your classmates!