NCLE EXAM, PRACTICE EXAM AND STUDY
GUIDE LATEST 2024 ACTUAL EXAM CONTAINS
600 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (VERIFIED
ANSWERS) |ALREADY GRADED A+
Diffused Illumination - ANSWER -Uses widest slit, longest aperture
-Light source positioned at an angle of 40º-50º
-Used to view overall areas, to observe the ocular adnexa, cornea, sclera, lids,
conjunctiva, lens surface, and CL fitting characteristics
Direct Illumination - ANSWER -Most important/useful illumination
-Light source positioned at an angle of 40º-50º to oculars
-Light beam and oculars are focused in coincidence on area being evaluated
-The difference in the illumination is not the angle used, but where the beam is
directed or focused and the width
-Varying width and aperture creates different illuminations
Optic(al) Section - ANSWER -Type of direct illumination that uses a narrow beam
to create a cross-section of the cornea
-Used to illuminate and observe individual layers of the cornea and tear film
-Used to evaluate corneal thickness, thinning, distortions, or depth of a foreign body
-Shows corneal-lens relationship
Parallelepiped - ANSWER -Type of direct illumination
-Uses a 0.5-3.0 mm beam and a 40º-50º angle to create a 3-D cube
-Used to assess width, depth, and height of an object within the cornea
-Useful in observing scars, infiltrates, staining, and the corneal-lens relationship
Indirect Illumination - ANSWER -Light source is moved out-of-click, the beam is 2-
3 mm wide and is positioned next to the area being studied
-Illuminated area is translucent or opaque, allowing for observation adjacent to
illumination
-Used to observe foreign bodies, corneal nerves, and opacities
-Oscillation of light accentuates details
Retroillumination - ANSWER -Light source is out-of-click, moved to the side of the
area being observed
-Using a 1-3 mm beam, the light is reflected off the iris and used to back-light the
area studied
-Useful in examining corneal scars, debris, microcysts, scratches on the lens, sub-
epithelial changes, corneal vascularization, diffuse edema, and surface deposits
, Sclerotic Scatter - ANSWER -Uses a focused parellelepiped placed out-of-click
directed at the limbus
-Oculars are not used
-The light is dispersed at the limbus, reflected through the cornea, creating a
circumcorneal halo
-Used to observe edema, stromal folds, lens deposits, bubbles under the lens, lens
defects, and scratches
Corneal Topography - Axial Map - ANSWER -Most widely understood map of the
cornea for many CL fitters
-Overall shape of the cornea
-Colors relate to steepness/flatness
-Sagittal reading measures the curvature of the cornea in diopters and is called the
axial power map
-Calculates curvature rather than power
Corneal Topography - Tangential Map - ANSWER -More sensitive map of the
cornea
-Calculates corneal curvature based on the tangent to normal
-Found to be more beneficial in identifying corneal pathology
-Not used as frequently to fit CLs
Corneal Topography - Refractive Power Map - ANSWER -Show spherical
aberrations
-More useful when assessing visual performance of post refractive patients
Corneal Topography - Elevation Map - ANSWER -Shows the difference in the
elevation of the cornea
-Measured in microns
Corneal Topography - Irregularity Map - ANSWER -Similar to elevation maps
-Uses best fit toric surface as a reference
-Eliminates any toricity from the eye and displays the elevation differences
Corneal Topography - Photokeratoscopic Views - ANSWER Uses the placido rings
which are reflected onto the eye to subjectively determine the location and regularity
of the rings
Corneal Topography - Numerical Views - ANSWER -Arranges individual
keratometric findings to depict curvature readings of the eye
-Extremely useful when fitting specialty contacts
-Corneal topographic software calculates the "average keratometric" value
Corneal Topography - Keratometry Views - ANSWER -Represent the keratometric
readings along with the axes of the eye's presumed astigmatism
-Dioptric values define the findings from the center of the cornea to the periphery
-This view helps the practitioner to quickly determine if corneal astigmatism is
symmetrical
GUIDE LATEST 2024 ACTUAL EXAM CONTAINS
600 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (VERIFIED
ANSWERS) |ALREADY GRADED A+
Diffused Illumination - ANSWER -Uses widest slit, longest aperture
-Light source positioned at an angle of 40º-50º
-Used to view overall areas, to observe the ocular adnexa, cornea, sclera, lids,
conjunctiva, lens surface, and CL fitting characteristics
Direct Illumination - ANSWER -Most important/useful illumination
-Light source positioned at an angle of 40º-50º to oculars
-Light beam and oculars are focused in coincidence on area being evaluated
-The difference in the illumination is not the angle used, but where the beam is
directed or focused and the width
-Varying width and aperture creates different illuminations
Optic(al) Section - ANSWER -Type of direct illumination that uses a narrow beam
to create a cross-section of the cornea
-Used to illuminate and observe individual layers of the cornea and tear film
-Used to evaluate corneal thickness, thinning, distortions, or depth of a foreign body
-Shows corneal-lens relationship
Parallelepiped - ANSWER -Type of direct illumination
-Uses a 0.5-3.0 mm beam and a 40º-50º angle to create a 3-D cube
-Used to assess width, depth, and height of an object within the cornea
-Useful in observing scars, infiltrates, staining, and the corneal-lens relationship
Indirect Illumination - ANSWER -Light source is moved out-of-click, the beam is 2-
3 mm wide and is positioned next to the area being studied
-Illuminated area is translucent or opaque, allowing for observation adjacent to
illumination
-Used to observe foreign bodies, corneal nerves, and opacities
-Oscillation of light accentuates details
Retroillumination - ANSWER -Light source is out-of-click, moved to the side of the
area being observed
-Using a 1-3 mm beam, the light is reflected off the iris and used to back-light the
area studied
-Useful in examining corneal scars, debris, microcysts, scratches on the lens, sub-
epithelial changes, corneal vascularization, diffuse edema, and surface deposits
, Sclerotic Scatter - ANSWER -Uses a focused parellelepiped placed out-of-click
directed at the limbus
-Oculars are not used
-The light is dispersed at the limbus, reflected through the cornea, creating a
circumcorneal halo
-Used to observe edema, stromal folds, lens deposits, bubbles under the lens, lens
defects, and scratches
Corneal Topography - Axial Map - ANSWER -Most widely understood map of the
cornea for many CL fitters
-Overall shape of the cornea
-Colors relate to steepness/flatness
-Sagittal reading measures the curvature of the cornea in diopters and is called the
axial power map
-Calculates curvature rather than power
Corneal Topography - Tangential Map - ANSWER -More sensitive map of the
cornea
-Calculates corneal curvature based on the tangent to normal
-Found to be more beneficial in identifying corneal pathology
-Not used as frequently to fit CLs
Corneal Topography - Refractive Power Map - ANSWER -Show spherical
aberrations
-More useful when assessing visual performance of post refractive patients
Corneal Topography - Elevation Map - ANSWER -Shows the difference in the
elevation of the cornea
-Measured in microns
Corneal Topography - Irregularity Map - ANSWER -Similar to elevation maps
-Uses best fit toric surface as a reference
-Eliminates any toricity from the eye and displays the elevation differences
Corneal Topography - Photokeratoscopic Views - ANSWER Uses the placido rings
which are reflected onto the eye to subjectively determine the location and regularity
of the rings
Corneal Topography - Numerical Views - ANSWER -Arranges individual
keratometric findings to depict curvature readings of the eye
-Extremely useful when fitting specialty contacts
-Corneal topographic software calculates the "average keratometric" value
Corneal Topography - Keratometry Views - ANSWER -Represent the keratometric
readings along with the axes of the eye's presumed astigmatism
-Dioptric values define the findings from the center of the cornea to the periphery
-This view helps the practitioner to quickly determine if corneal astigmatism is
symmetrical
