pcl lab final

a patient with the following spectacles Rx: -1.75-1.75x180 and keratometric reading of 44.00@ 180/45.75@090 came for an

RGP evaluation. If the trial lens of -3.00 is used, giving an over refraction of +1.00, what would most likely be the BC radii

and power of the CL to be ordered:

a. BCR 7.76mm, power -1.75

b. BCR 7.71mm, power -2.00

c. BCR 7.63mm, power -2.00

d. BCR 7.63mm, power -1.7

c. CR 7.63mm, power -2.00 *take BCR at refractive axis)

calculate the residual astigmatism for the following refractive parameters: spectacle Rx: -3.00 -1.50x090,

44.00@090/46.25@180 if fitted with RGP lenses:

a.-1.00x090

b. +0.75x090

c. -1.00x180

d. -0.75x090

c. -1.00x180

if the same patient was fitted with spherical soft lenses, what would most likely be the residual astigmatism:

a. -1.50x090

b. -1.00x180

c. -0.75x180

d. -1.25x090 

d. -1.25x090 

a patient with the following refraction OS: +1.75-1.00X180 and “K” reading of 45.00@180/45.50@090, came for an RGP

evaluation. If over refraction of -1.00-1.50x180 was obtained when fitted with a trial lens of +3.00. what would most likely

be the diagnostic base curve radii?

a. 7.42mm

b. 7.46mm

c. 7.38mm

d. 7.54mm

d. 7.54mm take BCR at refractive axis (180)

For the above pt what would most probable be the final front surface toric RGP lens to be ordered?

a. +0.50 +1.50x100

b. +2.00-1.75x090

c. +0.50+1.70x090

d. +2.00-1.50x170

a. +0.50 +1.50x100

A pt with the following refraction -4.75 -2.00 x145, came for a soft toric CL evaluation. The trial lens used was

-3.50-1.75x135. The lens rotated 15o counter clockwise, spherical over refraction was -1.00 with acuity of 20/25. What

would most likely be the prescription to be ordered?

a. -4.50-1.75x120

b. -4.50-1.75x160

c. -4.75-2.00x120

d. -4.50-1.75x130 

-4.50-1.75x130 Rotated right, so LARS to fix from SPECTACLE RX AXIS!

From the following refractive data which patient most likely be the best candidate for Back Surface Toric RGP

a. b. spectacle Rx -2.00-2.75x090; K’s 44.50@090/47.75@180

spectacle Rx +1.50-3.00x090; K’s 42.25@090/45.50@180

c. spectacle Rx -1.50-1.00x090; K’s 45.00@090/47.00@180

d. spectacle Rx +0.75-2.00x090; K’s 43.00@090/46.00@180

c. spectacle Rx -1.50-1.00x090; K’s 45.00@090/47.00@180 CA > RA

calculate the induced cylinder if we have a patient fitted with a bi-toric lens and the following refractive data: spectacle Rx

-2.00-4.00x180, K’s 42.50@180/46.50@090.

a. -3.50x180

b. -2.00x180

c. -4.00x180

d. -1.75×180

d. -1.75×180

The following statements are true regarding aspherical lenses EXCEPT:

a. Aspheric lenses flatten from center to the periphery

b. Aspheric lenses with higher eccentricity value are used to correct presbyopia

c.As the diameter increase the edge lift decrease

d. Aspheric lenses align more precisely with the aspheric shape of the cornea

a. Aspheric lenses flatten from center to the periphery

A patient came to your office and had the following refractive data: spectacle Rx: -1.75 -3.25 x180 K’s

43.50@180/46.50@090, what would most likely be the predicted over refractive if a trial lens of pl/-3.00 with 43.00/46.00

was chosen.

a. -1.25

b. -1.25-0.25x180

c. -2.25

d. -1.75

a. -1.25

With the above data, what would most likely be the CL to be ordered?

a. -1.25/-4.50 CPE

b. -2.25/-4.25 SPE

c. -2.25/-4.75 CPE

d. -1.25/-4.25 SPE

d. -1.25/-4.25 SPE

When fitting a patient after penetrating keratoplasty surgery which of the following statement best describes why hydrogel

lenses should NOT be used in this patient?

a. Hydrogel lenses could cause normal erosion in the donor graft

b. Hydrogel lenses could increase the risk of graft rejection due to hypoxia

c. Hydrogel lenses could increase the risk of corneal edema

d. Hydrogel lenses could reduce healing process

b. Hydrogel lenses could increase the risk of graft rejection due to hypoxia

a patient came to your office with the following refractive data: spectacle Rx +1.75 -3.50 x180 K’s 41.75@180/43.75@090.

what would most likely be the predicted over refraction if a lens of PL/-3.00, 41.50/44.50 was chosen

a. +2.00 -5.50 x180

b. +2.00 -2.50 x180

c. +2.00-1.50x180

d. +0.50-2.00x090

c. +2.00-1.50x180

with the above data what would most likely be the CL to be ordered:

a. +2.00/-5.50 CPE

b. +2.00/+0.50 CPE

c. +2.00/-2.50 CPE

d. +2.00/-5.50 SPE

c. +2.00/-2.50 CPE "high corneal toricity"

A keratoconus patient came to your office, you found the following ”K” reading 48.75@030/53.25@120. what initial

diagnostic BC radius you would most likely select to fit this patient, if a CLECK study lens is going to fit (apical clearance)

a. 6.22mm

b. 6.34mm

c. 6.91mm

d. 6.49mm

b. 6.34mm

Comparing the cornea of a normal patient the cornea of a patient, which underwent radial keratotomy which statement

best describes their shape?

a. A normal cornea the central area is steeper and flatten toward the periphery, the cornea of a post-operative radial keratototmy the central area is flatter than the periphery

b. The shape of a normal cornea is like a plateau, the shape of a post operative radial keratototmy is flatter in the center and steeper toward the periphery

c. The shape of a normal cornea and a post operative radial keratotomy are the same, steeper in the center and flattens toward the periphery

d. The shape of a normal cornea is flatter in the center and steeper toward the periphery, the shape of a post-operative radial keratotomy is steeper at the center and flattens toward the periphery

a. A normal cornea the central area is steeper and flatten toward the periphery, the cornea of a post-operative radial keratototmy the central area is flatter than the periphery

front surface toric lenses are best recommended for

a. spherical refraction

b. high cylinder

c. oblique astigmatism

d. spherical corneas

d. spherical corneas

in which of the following condition orthokeratology could be performed with good results:

a. hyperopia

b. Aphakia

c. Astigmatism

d. Myopia

d. Myopia

all the following are methods for stabilization toric lenses except:

a. prism ballast

b. thin zone

c. spin cast

d. truncation

c. spin cast

A presbyopic pt came to your office for a bifocal CL fitting. His spectacle Rx is +2.00 OU add +2.00. After trial lens for, with

Sunsoft multifocal lens, the patient respond that with a +0.25 distance acuity blurred but near acuity improved. What new

CL Rx will be best solve the problem?

a. b. Prescribe +2.50 on dominant eye, +2.75 on non-dominant eye, with bifocal B

b. Prescribe +2.50 OU with bifocal B

c. d. Prescribe +2.00 on dominant eye, +2.25 on non-dominant eye, with bifocal B

d. Prescribe +2.75 on dominant eye, +2.50 on non-dominant eye, with bifocal B

c. d. Prescribe +2.00 on dominant eye, +2.25 on non-dominant eye, with bifocal B

Three point touch design describe an RGP lens that it is fit with three areas of light bearing. These three areas of bearing are

located:

a. apex, mid periphery, periphery

b. mid-periphery, apex, mid-periphery

c. periphery, apex, periphery

d. periphery, mid-periphery, periphery

b. mid-periphery, apex, mid-periphery

Which of the following statements best describe the differences between an OK series lens and a conversational tri-curve lens?

a. An OK series lens the secondary curve is flatter than the base curve; in a conversational tri-curve designs the secondary curve is steeper

b. The diagnostic base curve of a conventional tri-curve should be 0.50D steeper than alignment, in the OK series it

should be selected 1.50 to 2.00D flatter than K

lens?

c. The OK series lens yields rapid corneal changes, as compared with the conversational tri-curve lens

d. The OK series lens diagnostic fitting is not important as with convention tri-curve in which diagnostic fitting is essential.

c. The OK series lens yields rapid corneal changes, as compared with the conversational tri-curve lens

A pt with refractive data came for RGP evaluation. Spectacle Rx +3.50-1.50 x180, K’s 43.50@180/45.50@090. if a diagnostic

BC radius of 43.75 was used and an over refraction of -1.25 -0.50x090 was obtained. What would most likely be the

diagnostic lens power?

a. +3.00

b. +4.40-0.50x180

c. +4.00

d. +5.00D

d. +5.00D

a pt came to your office looking for RGP lenses. Spectacle Rx -1.50 -1.50x180 K’s 43.50@180/45.00@090, a diagnostic lens

of -3.00 was used giving an over refraction of +1.50 -0.50 x090, what would most likely be the BC of the trial lens?

a. 43.00

b. 42.75

c. 43.50

c. 43.50 go with flatter for BC

a pt came to your office and the following results were obtained: Refraction -1.75 -1.00x095, K’s 43.25@095/44.25@005. if

an over refraction of +1.00 was obtained using a diagnostic lens of 43.00 BC. What would most likely was the diagnostic lens

power used?

a. -2.50

b. -3.50

c. -2.00

d. -3.00

a. -2.50

pt came to your office and had refractive data: spectacle Rx +1.75 -3.25 x180; K’s 43.25@180, 46.50@090, what would most

likely be the predicted over refraction and CL power ordered, if a trial lens of pl/-3.00 with 43.00/46.00 ?

a. OR +2.00-1.00X180, power -1.00/+2.00 CPE

b. OR +1.00, power -1.00/+2.00 SPE

c. OR +2.00, power +2.00/-1.00 SPE

d. OR +1.00, power +2.00+2.00/-1.00 SPE

c. OR +2.00, power +2.00/-1.00 SPE

From the above pt calculate the induced cylinder

a. -3.00

b. -1.50

c. -1.75

d. -2.00

b. -1.50

a pt came to your office and has the following refractive data: OD spectacle Rx -2.25 -1.75 x090; K’s

42.50@090/43.00@180. you decide to fit a Front surface Toric RGP . A trial lens of 42.75 was used giving an OR of -0.50 -1.00

x090. the power of the diagnostic lens most probably used was.

a. -3.00

b. -2.50

c. -3.50

d. -2.00

d. -2.00

from the above pt what would most likely be the power of the lens to be ordered

a. -3.50 +1.00 x170

b. -2.50 +1.00 x180

c. -2.50 +1.00 x170

d. -3.50 +1.00 x080

a. -3.50 +1.00 x170

a pt with spectacle Rx +2.50 -1.25 x180 came to be fitted with RGP lenses. A diagnostic lens of power +3.00 and 44.75 BC

was used giving an over refraction of -0.25 -0.50 x090. what would most probably be the K readings?

a. 44.00@180/46.50@090

b. 44.50@180/46.25@090

c. 44.25@090/46.50@180

d. 45.00@180/46.50@090

b. 44.50@180/46.25@090

bonus

from above pt, what would most likely be the power of the lens to be ordered?

a. +2.50

b. +2.00

c. +3.00

d. +2.25

a. +2.50