Visual Field Flashcards
visual field
the extent in which objects can be seen depend on the stimulus and location
isopter
the distribution of points that demarcates the area in which one can see and not see a specified stimulus
kinetic field testing
stimulus is moved towards point of fixation until it is seen
static field testing
stimulus is placed at a specific location within the field and size/intensity is increased until seen
manual visual field
Confrontation Visual field, Goldmann visual field, Tangent screen
SCREENING
accurate
automated visual field
humphrey visual field and octopus visual field
PROBLEM-RELATED
quantitative tests, sensitive and reproducible
central visual field
the central point of fixation where the fovea is located is most sensitive to find details and colors
Most sensitive
fovea
central part of macula
highest concetration of cone photoreceptors (color and detail)
peripheral visual field
further away from fovea, more form/motion based due to less cones and more rods
Least sensitive
Hill of vision
normal “island” of vision where the “hill” is located at the greatest visual sensitivity
normal monocular visual field
in degrees
temporal: 100 degrees
nasal: 60 degrees
superior: 60 degrees
inferior: 75 degrees
physiological blind spot
where the optic nerve is, about 15 degrees temporal from fixation
(in the fourth quadrant)
same side as same eye
causes of defects in visual field
lesions along visual pathway
importance of visual field
patients are less likely to notice peripheral problems on their own
location of visual field defects can pinpoint which part of the brain has been affected
Optic nerve defect
will present defect in only one eye
