NCLE BASIC EXAM
STUDY QUESTIONS (SET 2025) |
GUARANTEED ACCURATE
ANSWERS
Diffused Illumination - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -
More sensitive map of the cornea
-Calculates corneal curvature based on the tangent to normal
-Found to be more beneficial in identifying corneal pathology
STUDY QUESTIONS (SET 2025) |
GUARANTEED ACCURATE
ANSWERS
Diffused Illumination - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -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 - ACCURATE ANSWERS✔✔ -
More sensitive map of the cornea
-Calculates corneal curvature based on the tangent to normal
-Found to be more beneficial in identifying corneal pathology
