Astigmasim and Presbyopia

Question 1

When parallel rays of light enter the eye with accommodation relaxed

Answer 1

Astigmatism

Question 2

When the cornea has unequal curvature on the anterior surface

Answer 2

Corneal Astigmatism

Question 3

When the crysalline lens has an unequal curvature on the surface or in its layer

Answer 3

Lenticular Astigmatism

Question 4

Total Astigmatism= ________+ ________

Answer 4

Corneal +residual

Question 5

When the two principal meridians are perpendicular to each other

Answer 5

Regular Astigmatism

Question 6

Minus cylinder axis around horizontal meridian

Also the most common type of astigmatism based on the orientation of meridians

Answer 6

With-The-Rule (WTR) Astigmatism

Question 7

Minus cylinder axis around vertical meridian

Answer 7

Against-The-Rule (ATR) Astigmatism

Question 8

When the two principal meridians are not perpendicular to each other

Answer 8

Irregular Astigmatism

Question 9

When one of the principal meridians is focused in front of the retina and the other is focused behind the retina

Answer 9

Mixed Astigmatism

Question 10

When both principal meridians are focused behind the retina with accommodation relaxed

Answer 10

Compound hyperopic Astigmatism

Question 11

Give at least 3 clinical test for Astigmatism

Answer 11

Autorefraction
Keratotomy
Retinoscopy

Question 12

Symptoms of Astigmatism

Answer 12

Distorted vision at distance and near
Headaches
Squinting

Question 13

Prevalence of Astigmatism

Answer 13

Age
Gender
Ethnicity

Question 14

The principal meridians or axes of the two eyes are not symmetrical

Answer 14

Asymmetrical Astigmatism

Question 15

Both eyes are WTR Astigmatism, and the sum of the two axes equal approximately 180

Answer 15

Symmetrical Astigmatism

Question 16

The inability of the human eye to focus on objects up close that results with aging

Answer 16

Presbyopia

Question 17

The amount of ciliary muscle contraction or effort/innervation required to produce a unit of change

Answer 17

H-H-G theory

Question 18

The amount of cilliary muscle contraction needed to produce a unit change

Answer 18

D-D-F theory

Question 19

Is the condition in which virtually no accomodative ability remains

Answer 19

Absolute presbyopia

Question 20

Condition which can still be overcome by a hard or forced cilliary effort

Answer 20

Facultative presbyopia

Question 21

The condition in which near vision difficulties results from an apparent decrease in the AA in dim light.

Answer 21

Nocturnal Presbyopia

Question 22

Symptoms of Presbyopia

Answer 22

Occipital headache
Diplopia
Pain around the eyes
Dizziness

Question 23

Mild laser hear is used in a three-second procedure to shrink collagen

Answer 23

Laser Thermal keratoplasty

Question 24

Is the maximum increase in optical power that an eye can achieve in adjusting its focus from as far as possible to the nearest possible

Answer 24

Amplitude or Accommodation

Question 25

A Small scale snellen’s chart

Answer 25

Near Chart VA

Question 26

Corrections for Presbyopia

Answer 26

Bifocals

Reading glasses

Question 27

With the use of contact lenses, it also eliminates the need for bifocal or reading glasses

Answer 27

Monovision

Question 28

Causes of Sclerosis

Answer 28

Nutritional changes

Question 29

The earliest stage at which symptoms or clinical findings documents the near visions effect of the condition

Answer 29

Incipient Presbyopia

Question 30

Adults patients eventually reports visual difficulties when faced with gradually declining accommodation amplitude

Answer 30

Functional presbyopia