Quiz 13 - Review for Exam 2 (I could not add pictures) Flashcards
Pts corneal radii are 44.00 180 / 44.50 090. What type of astigmatism is that?
WTR
What is the approximate thickness of an avg. cornea?
520um
A pt wears his CL on a daily basis. Which Dk/t value should his lenses have at minimum?
24
Which of the following components of CL solutions is a perservative? EDTA Pancreatin Saline Subtilisin
EDTA
Which of the following evaluates corneal staining after 3 months of lens wear? Andrasko COOKI Efron IER Matrix
IER matrix
Which 2 of the following instruments use placido discs? Auto-Keratometer Keratometer Orbscan 2 Pentacam Topographer
Orbscan 2 and Topographer
Which of the following is a GP lens material or material component?
a. HEMA
b. GMA
c. PMMA
d. SA
d. SA
How much astigmatism is left after a GP lens is fitted?
a. 100% corneal astigmatism, 100% internal astigmatism
b. 90% corneal astigmatism, 100% internal astigmatism
c. 10% corneal astigmatism, 90% internal astigmatism
d. 10% corneal astigmatism, 100% internal astigmatism
d. 10% corneal astigmatism, 100% internal astigmatism
Your refraction is -1.00-1.00 x180. Keratometry reveals 42.50 180/43.50 090. Which of the following lenses is the best fitting option?
a. Spherical GP lens (FSA)
b. Spherical soft lens (HEMA)
c. Toric GP lens (FSA)
d. Toric soft lens (HEMA)
a. Spherical GP lens (FSA)
Your pt has TBUT score of 20 seconds. What does that mean?
a. Pt likely does not suffer from dry eye
b. Pt. likely suffers from dry eye
c. Pt. requires a Soft lens
d. Pt tolerates GP lenses
Pt likely does not suffer from dry eye
Complete the sentence: When the water content of a SiHy lens increases, \_\_\_\_\_\_. Modulus increases Oxygen permeability increases Refractive index decreases Comfort decreases
Refractive index decreases
Which of the following is not associated to a steep fitting hydrogel lens?
a. Lack of movement
b. A well centered lens
c. Conjunctival vessel impingement
d. Unacceptable comfort
Unacceptable comfort
PMMA is the most commonly prescribed contact lens material in the US?
True or False.
False
Relative to extended wear, the risk of microbial keratitis with CL daily wear is ________ .
Decreased
Increased
The same
Decreased
Which 2 of the following stabilization methods are NOT stabilization methods used for toric soft lenses (select 2)? CN bevel Double slab off Front surface toricity Peri-ballast Prism Ballast Reverse Prism
CN bevel and Front surface toricity
The pts rx is plano -6.00 x 180. When wearing a -1.00 -5.00 x 180 toric soft lens, its stablization mark is oriented at the 6 o’clock position. Which of the following over refracting do you expect to find?
a. Plano
b. Plano - 1.00 x180
c. -1.00-1.00 x 090
d. +1.00-1.00 x 180
e. +1.00 -1.00 x 090
d. +1.00-1.00 x 180
Pts rx. is plano -3.00 x 170. A soft toric diagnostic lens plano -3.00 x 180 stabilizes at 5 o’clock. What do you order?
a. Plano -3.00 x 140
b. Plano -3.00 x 150
c. Plano -3.00 x 160
d. Plano -3.00 x 180
Plano -3.00 x 140
The pts. rx is plano-3.00 x 180. When wearing a plano -3.00x180 toric soft lens, over-refraction reveals a cylinder of 2.00DC. Based on this information alone, how much lens rotation do you expect to find?
a. 10 degrees
b. 15 degrees
c. 20 degrees
d. 30 degrees
20 degrees
A tetra curve GP lens with OAD 9.40mm is fit on a normal cornea with 0.00D corneal astigmatism. The BCR of the lens 0.50D flatter than the cornea’s Flat K. Which of the following would you expect to find, after instilling fluorescein?
a. Central pooling pattern
b. dumbbell shape pattern
c. perfect alignment pattern
d. apical touch pattern
c. Perfect alignment pattern
Consider OD of your pt. The refraction is plano -1.00 x 180. The K readings are 43.00 180 /44.00 090. A GP CL with BCR = 7.90mm is used. What is the required lens power? Plano -0.25 -0.50 \+0.25 \+0.50
+0.25
