Clinical Refractive Status Flashcards
Emmetropia
Normal
Ametropia
Abnormal
Myopia
nearsighted
focal point in front of retina
corrected with concave (-)
Hyperopia
farsighted
focal point behind retina
corrected with convex (+)
Anisometropia
refractive error in each eye is different
Myopia Causes
Axial length too long
Focuses too strong
hereditary or environmental
Hyperopia Causes
Axial Length too short
Focuses too weakly
Hereditary
Isoanisometropia
Both eyes + or -
Antimetropia
One eye + and the other -
Astigmatism
Light focuses differently along different meridians
Regular Astigmatism
Max and min refractive powers separated by 90 degrees
Irregular Astigmatism
Max and min refractive powers separated by more or less than 90 degrees
Corneal Astigmatism
Differences of curvature on the cornea causes light be be focused wrong
Lenticular Astigmatism
Toricity or tilting of lense causes light to be focused wrong
With the Rule Astigmatism
Horizontal meridian is flat
Vertical meridian is curved