Visual Fields Flashcards
Do you do VF dilated or undilated?
Undilated
Indications for a visual field
- performed as part of a comprehensive eye exam
- examination may not have access to a perimetric instrument
- perimetry is reserved for selected patients
Advantages of confrontational visual fields
- simplicity
- flexibility
- requires no specialized instrumentation
Disadvantages of confrontational visual field
- can not determine the exact size of field loss (QUALITATIVE)
- Lack of standardization
- not sensitive enough to detect subtle defects
How does the computer present stimuli in static perimetry
Random fashion
What us important for the random presentation in the static perimetry
Speed
What does static perimetry allow for
Storage of data
What is the most widely used instrument for VF
Humphrey visual field
What is the gold standard of visual field
Humphrey visual field
What do you do if you get abnormal findings on a patient?
Repeat test 2-3 times to make sure they are accurate
What quantifies the degree of reduction of sensitivity at each point tested
Target presentation: threshold
What is most helpful in following defects over time
Target presentation: Threshold
Provides a detailed map of each eyes deficit
Target presentation: threshold
What are the threshold strategies
- full threshold
- full threshold from prior data
- fast threshold
What is the standard for VF
SITA
This still uses method of determining threshold values for 4 primary points in each quadrant
SITA
These are used to generate starting levels of neighboring points
SITA
The result of this is that threshold determination is reached in a shorter amount of time, but with the same accuracy as a full threshold test, monitors test point results and utilizes a complex statistical technique which assigns a level of confidence for how close each point is
SITA
What is the main difference between SITA standard vs SITA fast
Levels of confidence the program needs to stop testing at a particular point
SITSA standard and certainty
Sets a higher level of certainty whihc requires more trials at a given point thus, it is more accurate