Refractive Status of the Human Eye Flashcards
Which answer best explains 20/20 vision?
a. It is identified as a quantitative measure that is identified as perfect vision.
b. It is identified as a quantitative measure that is identified as normal vision.
c. It is identified as a quantitative measure of the ability of the eye to identify the smallest elements of a letter (or object) to correctly identify the letter or object.
d. It is identified as a quantitative measure of the ability of the visual system to identify the smallest letter on the Snellen chart.
It is identified as a quantitative measure of the ability of the eye to identify the smallest elements of a letter (or object) to correctly identify the letter or object.
Which identifies the smallest angle?
a. Visual angle
b. Minimum visual angle
c. Subtended angle
d. Minimum subtended visual angle.
Minimum visual angle.
Which best identifies the visual system?
a. Plus
b. Minus
c. Aspheric
d. Lenticular
Plus
Of the four major refracting mediums of the eye, which has the greatest power?
a. Cornea
b. Aqueous humor
c. Crystalline lens
d. Vitreous humor
Cornea
If the eye has too much plus power, what is the refractive error?
a. Astigmatism
b. Presbyopia
c. Hyperopia
d. Myopia
Myopia
If the eye has too little plus power, what is the refractive error?
a. Astigmatism
b. Presbyopia
c. Hyperopia
d. Myopia
Hyperopia
If light rays come to a point focus at one place in front of the retina, what is the refractive error?
a. Astigmatism
b. Presbyopia
c. Hyperopia
d. Myopia
Myopia
If light rays come to a point focus at one place in front of the retina, and another place behind the retina, what is the refractive error?
a. Mixed astigmatism
b. Compound astigmatism
c. Irregular astigmatism
d. Simple astigmatism
Mixed astigmatism
If light rays come to a point focus at one point in front of the retina in one principle meridian, and one point on the retina in the opposite principle meridian, what is the refractive error?
a. Compound myopic astigmatism
b. Simple myopic astigmatism
c. Compound hyperopic astigmatism
d. Simple hyperopic astigmatism
b. Simple myopic astigmatism
If light rays come to a point focus at one point behind the retina, what is the refractive error?
a. Astigmatism
b. Presbyopia
c. Hyperopia
d. Myopia
Hyperopia
If light rays come to a point focus at two different points behind the retina in opposite principle meridians, what is the refractive error?
a. Compound myopic astigmatism
b. Simple myopic astigmatism
c. Compound hyperopic astigmatism
d. Simple hyperopic astigmatism
Compound hyperopic astigmatism
If light rays come to a point focus at two different points in front of the retina in opposite principle meridians, what is the refractive error?
a. Compound myopic astigmatism
b. Simple myopic astigmatism
c. Compound hyperopic astigmatism
d. Simple hyperopic astigmatism
Simple myopic astigmatism
If all light rays come to a point focus on the retina, what is the condition?
a. Ametropia
b. Presbyopia
c. Emmetropia
d. Astigmatism
Emmetropia
What is a general term for any error of refraction in the eye?
a. Ametropia
b. Presbyopia
c. Emmetropia
d. Astigmatism
Ametropia
Nearsighted is also referred to as what?
a. Short sight
b. Long sight
c. Boss eyed sight
d. Cross eyed sight
Short sight
Farsighted is also referred to as what?
a. Short sight
b. Long sight
c. Boss eyed sight
d. Cross eyed sight
Long sight
The condition in question 15 (Nearsighted / Short sight) is corrected with what type of lens?
a. Concave
b. Convex
c. Meniscus
d. Sphero-cylinder
Concave
The condition in question 16 (Farsighted / Long sight) is corrected with what type of lens?
a. Concave
b. Convex
c. Meniscus
d. Sphero-cylinder
Convex
The correction for a condition whereby light rays focus on the retina in one principle meridian and in front of the retina in the opposite principle meridian would be illustrated by what Rx?
a. -3.00 -2.00 x 180
b. +3.00 -2.00 x 180
c. Plano -2.00 x 180
d. +3.00 +2.00 x 180
Plano -2.00 x 180
The correction for a condition whereby light rays focus in front of the retina in two places in opposite principal meridians would be illustrated by which Rx?
a. -3.00 -2.00 x 180
b. +3.00 -2.00 x 180
c. Plano -2.00 x 180
d. +3.00 +2.00 x 180
-3.00 -2.00 x 180
The correction for a condition whereby light rays focus behind the retina in two places in opposite meridians would be illustrated by which Rx?
a. -3.00 -2.00 x 180
b. +3.00 -2.00 x 180
c. Plano -2.00 x 180
d. +3.00 +2.00 x 180
+3.00 +2.00 x 180
The correction for a condition whereby light rays focus in front of the retina in one place and behind the retina in the opposite principle meridians would be illustrated by which Rx?
a. -3.00 -2.00 x 180
b. +3.00 -2.00 x 180
c. Plano -2.00 x 180
d. +3.00 +2.00 x 180
+3.00 -2.00 x 180
The correction for a condition whereby light rays come to a point focus in front of the retina would be illustrated by which Rx? a. -3.00 -2.00 x 180 b. +3.00 +2.00 x 180 c -3.00 Sphere d. +3.00 Sphere
-3.00 sphere
The correction for a condition whereby light rays come to a point focus behind the retina would be illustrated by which Rx? a. -3.00 -2.00 x 180 b. +3.00 +2.00 x 180 c -3.00 Sphere d. +3.00 Sphere
+3.00 sphere
Irregular astigmatism is the condition whereby ____:
a. The principle meridians are not at right angles to one another and the condition is better corrected with the use of contact lenses
b. The principle meridians are at right angle to one another and the condition is better corrected with the use of contact lenses
c. The principle meridians are not at right angles to one another and the condition is not better corrected with the use of contact lenses
d. The principle meridians are at right angles to one another and the condition is not better corrected with the use of contact lenses
The principle meridians are not at right angles to one another and the condition is better corrected with the use of contact lenses
If a 45 year old patient presents with the chief complaint as seeing well to read during the day, but needing more light to read at night, what may be their condition?
(Note: Opticians don’t diagnose, but should be able to identify certain conditions)
a. Astigmatism
b. Presbyopia
c. Hyperopia
d. Myopia
Presbyopia
What is the cause of the condition in question 26 (Presbyopia)?
a. Loss of moisture in the eye
b. Having poor tear quality
c. Hardening of the crystalline lens
d. Using one’s eyes under poor lighting conditions
Hardening of the crystalline lens
The ability to accommodate can be identified as:
a. Seeing up close with over-the-counter reading glasses
b. The plussing of the capsule of the eye when looking at near objects
c. The bulging of the capsule of the eye when looking at near objects
d. The bulging or plussing of the crystalline lens of the eye when looking at near objects
The bulging or plussing of the crystalline lens of the eye when looking at near objects
I addition to reduction in accommodative ability, presbyopic patients may also experience_____:
a. Reduction in contrast sensitivity
b. Reduced ability to cope with glare
c. Slower visual processing
d. All of the above
All of the above
Correction for presbyopia includes ______:
a. Bifocals
b. Single vision readers
c. Progressive addition lenses
d. All of the above
All of the above
______ means eyes that are “carried correctly” and proper extraocular muscle tonicity is maintained:
a. Orthotropia
b. Orthophoria
c. Heterophoria
d. Heterotrophia
Orthophoria
_____ is the state of slight contraction of all six extraocular muscles of the eye while at rest in order to hold the eye steady in a fixed position.
a. Fusion
b. Diplopia
c. Tonicity
d. Strabismus
Tonicity
_____ is double image caused by a muscular imbalance in one or more muscles of the eye overcoming the brains desire for fusion.
a. Fusion
b. Diplopia
c. Tonicity
d. Strabismus
Diplopia
_____ is a disorder in which the two eyes are not correctly aligned. It is also referred to as squint, or crossed-eyes:
a. Fusion
b. Diplopia
c. Tonicity
d. Strabismus
Strabismus
The following Rx is an indication of what type of disorder? OD -5.00 -1.00 X 180 OS +2.00 -1.00 x 180 a. Anisometropia b. Antimetropia c. Aniseikonia d. Iseikonia
Antimetropia
The following Rx is an indication of what type of disorder? OD +5.00 -1.00 X 180 OS +2.00 -1.00 x 180 a. Anisometropia b. Antimetropia c. Aniseikonia d. Iseikonia
Anisometropia
The conditions referred to in questions 35 & 36 (Antimetropia & Anisometropia) create a condition whereby two unequal images are sent by the eyes to the brain. What is that condition?
a. Anisometropia
b. Antimetropia
c. Aniseikonia
d. Iseikonia
Aniseikonia
What variables are used to produce iseikonic lenses?
a. Center thickness, index of refraction, vertex distance, power
b. Center thickness, vertex distance, power, slab off
c. Base curve, center thickness, slab off, vertex distance
d. Base curve, center thickness, index of refraction, vertex distance
Base curve, center thickness, index of refraction, vertex distance
A term that refers to the definite turning out of an eye is _____:
a. Esotropia
b. Exotropia
c. Hypertropia
d. Hypotropia
Exotropia