Contact Lens Equipment and Measurements : Corneal Topography / Dry Eye Flashcards
What maps the corneal curvature and elevation?
Corneal Topography
What are the purposes of corneal topography?
Monitor Corneal Changes
Fit contact lenses based on curvature
Pre and post refractive surgery
What colors are steeper curvature?
Red / Warm
What colors are flatter curvature?
Green / Cooler
What are the types of maps?
Axial
Tangential
Elevation
Corneal Thickness
What type of map :
- Corneal power
- Good overview
Axial
What type of map :
- Power and curvature at individual points
- Most accurate
Tangential
What calculates elevation?
Placedo disc
What : actual elevation measured
Scheimpflug
What type of test asses and evaluate lipid layer?
Tear Break Up Time
What type of schirmer test is with no anesthetic?
Basal and Reflex
Test 1
What type of schrimer test is with anesthetic?
Basal
Test 2
What is scale is the same for every topography map?
Absolute
What scale emphasizes?
Normalized
What measures ant and post surface of cornea?
Sheimpflug
What measures thickness of the cornea?
Pachymetry
What dye is used for TBUT?
Fluorescein
What is the biggest layer of the tear film?
Aqueous
What is the tear film?
Lipid
Aqueous
Mucus
What type of assessment is putting a filter paper in th eye?
Schirmer Test
What type of assessment is putting thread in the eye?
Phenol Red Test