Crystalline Lens, Presbyopia and Cataracts

Question 1

The anterior-most layers of the crystalline lens are called:

a. Nucleus
b. Cortex
c. Subcapsular epithlium
d. None of the above

Answer 1

None of the above

Question 2

Cataracts will only form in the nucleus of lens.

a. True
b. False

Answer 2

False

Question 3

The amplitude of accommodation for the average 50 year old is approximately:

a. 1.00 diopter
b. 2.50 diopters
c. 4.00 diopters
d. 6.00 diopters

Answer 3

1.00 diopter

Question 4

The lens and capsule is surrounded by a fluid called vitreous humor that nourishes the capsule and lens:

a. True
b. False

Answer 4

False

Question 5

As a patient ages, the lens becomes larger and more flexible.

a. True
b. False

Answer 5

False

Question 6

Ophthalmologists always wait for a cataract to ripen before extraction.

a. True
b. False

Answer 6

False

Question 7

The type of cataract extraction that causes the least insult or injury to the eyes is called:

a. Phakoemulsification
b. Otracapsular
c. Extracapsular
d. Couching

Answer 7

Phakoemulsification

Question 8

Prolonged periods of near vision use may lead to near point stress, and the development of:

a. Myopia
b. Hyperopia
c. Astigmatism
d. Cataracts

Answer 8

Myopia

Question 9

Sitting upright and reading or working at a longer distance may help prevent near point stress.

a. True
b. False

Answer 9

True

Question 10

When the cilliary muscle contracts it moves closer to the lens equator, relaxing the zonules (suspensory ligaments) and increasing the plus power of the lens.

a. True
b. False

Answer 10

False

Question 11

A hyperopic patient with presbyopia can remove his/her glasses to see clearly at near.

a. True
b. False

Answer 11

False

Question 12

Swelling of the area of the retina that is responsible for the central vision following cataract surgery is called:

a. Corneal edema
b. Papilledema
c. Cystoid macular edema
d. None of the above

Answer 12

Cystoid macular edema

Question 13

A secondary cataract forms:

a. In the cortex
b. In the nucleus
c. In the subcapsular epithelium
d. In the posterior capsule

Answer 13

In the posterior capsule

Question 14

Cataract surgery can now be performed using a laser to remove the lens.

a. True
b. False

Answer 14

False

Question 15

Presbyopia is caused by loss of:

a. Elasticity of the capsule
b. Cilliary muscle tone
c. Elasticity of the lens
d. All of the above

Answer 15

All of the above

Question 16

A congenital cataract is the result of:

a. Traumatic injury
b. Smoking
c. Birth
d. Exposure to ultraviolet light

Answer 16

Birth

Question 17

At birth, a child will have approximately _____ diopters of accommodation:

a. 4-6
b. 8-10
c. 12-14
d. 16-18

Answer 17

16-18

Question 18

Monovision is a fitting/surgical technique used to allow one eye to see near, while the other sees in the distance. It is preferable to fit the dominant eye with the near Rx.

a. True
b. False

Answer 18

False

Question 19

The lens is composed primarily of water and protein.

a. True
b. False

Answer 19

True

Question 20

The fibers that comprise the lens are about 10nm long and _____ in shape.

a. Cresent
b. Square
c. Oval
d. Hexagonal

Answer 20

Crecent