CONTACT LENS (HARD&SOFT) (1.0) Flashcards
- The cornea is thinnest
A. Upon awakening B. One hour after awakening C. During sleep D. Just prior to sleep E. One hour prior to awakening
D. Just prior to sleep
- The water content of a hydrocurve lens is approximately
A. 30%
B. 45%
C. 54%
D. 21%
C. 54%
- In general, the soft lens is recommended when the
A. Spherical ametropia is between +20 to -20 D
B. Refractive astigmatism is less than 3.00 D
C. Corneal radius is between 39.00
and 49.00
D. Corneal toricity is 2.00 D or less
Both A and D are correct
A. Spherical ametropia is between +20 to -20 D
D. Corneal toricity is 2.00 D or less
- Which of the following conditions (disorders) prevents hard contact lens wear?
A. Diabetes
B. Allergy
C. Color blindness
D. Asthma
Both A and D are correct
A. Diabetes
D. Asthma
- Which of the following statements concerning Image size with contact lenses is correct?
A. The retinal image size is smaller for a myope corrected with contact lenses instead of spectacles
B. The retinal image size is greater for a myope corrected with contact lenses instead of spectacles
C. The retinal image size is greater for a hyperope corrected
with contact lenses instead of spectacles
B. The retinal image size is greater for a myope corrected with contact lenses instead of spectacles
- Which of the following eye conditions will not prevent hard contact lens wear?
A. Trichiasis B. Blepharitis C. Meibomianitis D. Chalazion E. Hordeolum
A. Trichiasis
- Silicone lenses are highly permeable to
A. Oxygen
B. Carbon dioxide
A and B
A. Oxygen
B. Carbon dioxide
- Regarding diurnal variation in central corneal curvature, is found that the cornea is
A. Flattest in the morning
B. Steepest in the early evening
A and B
A. Flattest in the morning
B. Steepest in the early evening
- The plus series soft lens has a front surface radius of
A. 6.2 mm
B. 6.7 mm
C. 7.2 mm
D. 7.7 mm
B. 6.7 mm
- The hydrogel lens has little or no therapeutic application in which of the following pathological processes?
A. Bullous keratopathy B. Keratitis sicca C. Recurrent corneal ulcers D. Epithelial erosion E. Keratoconus
E. Keratoconus
- When compared to hard contact lenses, the hydrogel lens offers the distinct advantage of
A. Stabilized visual acuity
B. Durability
C. Reduced adaptation time
D. Minimal spectacle blur
Both C and D
C. Reduced adaptation time
D. Minimal spectacle blur
- Which of the following factors are enhanced with contact lenses in myopia?
A. Convergence B. Accommodation C. Usable field D. Aberrations E. Image size
Both C and E are correct
C. Usable field
E. Image size
- It is generally accepted that a hard contact lens with a posterior toric surface should be recommended when the corneal
astigmatism is
A. 0.00 D 0.50 D
B. 0.50 D 1.00 D
C. 1.00 D 2.00 D
D. 2.00 D or more
D. 2.00 D or more
- Prism ballasted anterior toric hard contact lenses are recommended to correct for internal residual astigmatism when the corneal astigmatism is below
A. 4.00 D
B. 3.00 D
C. 2.00 D
D. 1.00 D
C. 2.00 D
- The normal corneal thickness is approximately
A. 0.32 mm B. 0.42 mm C. 0.52 mm D. 0.62 mm E. 0.72 mm
C. 0.52 mm