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Opticianry - ABO Exam
Study terms covered in the ABO exam
185
Medical
Professional
10/03/2012

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Term
Aqueous Humor
Definition
The watery fluid in the anterior chamber
Term
Anterior Chamber
Definition
The front chamber of the eye between the cornea & the lens
Term
Lens Ciliary Body
Definition
The suspensory ligament attaches the ____ to the _____
Term
Aqueous Humor
Definition
The watery fluid in the anterior chamber
Term
Anterior Chamber
Definition
The front chamber of the eye between the cornea & the lens
Term
Lens Ciliary Body
Definition
The suspensory ligament attaches the ____ to the _____
Term
Posterior Chamber
Definition
The space between the iris and the lens
Term
Vitreous Chamber
Definition
The largest space, between the lens and eht retina
Term
tear layer, cornea, aqueous humor, crystalline lens and vitreous humor
Definition
Light passes through the transparent structures
Term
Corena
Definition
0.5 mm thick with 90% composed of stroma
Term
Epithelium, Bowman's Membrane, Stroma, Desemet's Memrane & Endothelium
Definition
5 layers that make up the cornea
Term
Epithelium
Definition
highly regenerative part of the cornea
Term
120 mil rods, 6 mil cones
Definition
Retina consists of
Term
Fovea
Definition
Greatest density of cones are in the
Term
increase
Definition
Radiating from the Fovea, cones decreas and rods
Term
Cones
Definition
Day vision, Detail, Color
Term
Rods
Definition
Night vision, Peripheral vision & black & white
Term
1.33
Definition
Aqueous Humor
Term
1.37
Definition
Cornea
Term
1.42
Definition
Crystalline Lens
Term
1.33
Definition
Vitreous Humor
Term
optic chasm
Definition
X-like structure where the optics nerves cross
Term
Geniculate Body
Definition
The optic nerve fibres end at the
Term
Visual cortex of the occipitl lobe
Definition
where the conscious recognition of visual impulses takes place.
Term
Fibrous Tunic
Definition
Outer protective coat of the eye. Consists of the cornea and
Term
Vascular Tunic
Definition
uveal tract. Consists of three parts: the iris ciliary body and the choroid
Term
Neural Tunic
Definition
Consists of the retina
Term
Tunics
Definition
structures of the eye may be grouped together to form __ or coverings
Term
accommodation
Definition
eye adjusts for viewing objects at various distances.
Term
accommodation
Definition
the ciliary muscle relaxes & allows the crystalline lens to thicken / change shape
Term
accommodation
Definition
eyes converge & pupils constrict
Term
2 mm
Definition
Subtract from dist. PD < 62 mm
Term
3 mm
Definition
Subtract from dist. PD 62 - 66 mm
Term
4 mm
Definition
Subtract from dist. PD > 66 mm
Term
Sclera
Definition
extra-ocular muscles are inserted into the __ and enable each eye to rotate
Term
6 extra-ocular muscles
Definition
Temporal rectus, nasal rectus, superior rectus, inferior rectus, superior and inferior oblique
Term
diplopia
Definition
double vision resulting from imbalances in the muscle strength
Term
Prism
Definition
included in RX to alleviate diplopia
Term
Phoria
Definition
a constant tendency for the eyes to turn from the normal position for binocular vision
Term
Tropia
Definition
a definite and obvious turning of the eyes from the normal position for binocular vision
Term
Right exophoria
Definition
tendency of the right eye to turn outward
Term
Left esotropia
Definition
definite turning inward of the left eye
Term
Rght hyperphoria
Definition
tendency of the right eye to turn upward
Term
Left hypotropia
Definition
definite turning downward of the left eye
Term
EXO
Definition
out
Term
ESO
Definition
in
Term
HYPER
Definition
up
Term
HYPO
Definition
down
Term
Emmetropia
Definition
light comes to focus directly on the retina when accommodation is relaxed
Term
Myopia
Definition
Light comes to focus in front of the retina (nearsighted)
Term
Hyperopia
Definition
Light comes to focus ibehind he retina (farsighted)
Term
Simple Myopic Astigmatism
Definition
One point comes to focus on the retina and one point comes to focus in front of the retina
Term
Simple Hyperopic Astigmatism
Definition
One point comes to focus on the retina and one point comes to focus behind the retina
Term
Compound Myopic Astigmatism
Definition
Both points of light come to focus in front of the retina
Term
Compound Hyperopic Astigmatism
Definition
Both points of light come to focus behind the retina
Term
Mixed Astigmatism
Definition
One point of light comes to focus in front of the retina, while the other comes to focus behind the retina
Term
six
Definition
The extra-ocular muscles are inserted into the sclera and serve to rotate the eye in all possible directions. There are _______of these muscles.
Term
Sclera & Cornea
Definition
The fibrous tunic is comprised of the:
Term
in the Brain
Definition
Fusion occurs:
Term
Ciliary Body
Definition
The aqueous fluid is continually being manufactured by
Term
Accommodation
Definition
The ability of the eye to bring objects of varying distances to focus on the retina is known as:
Term
Myopia
Definition
When accommodation is at rest, rays of light from a distant source come to focus in front of the retina. This condition is known as:
Term
Hyperopia
Definition
When accommodation is at rest, rays of light from a distant source come to focus behind the retina. This condition is known as
Term
optic nerve
Definition
Impulses are carried from the retina to the brain along the:
Term
he pupils constrict, The eyes converge, the crystalline lens accommodtes
Definition
While reading, or performing other near vision tasks:
Term
ovea centralis
Definition
The area of the retina capable of perceiving the greatest amount of detail is:
Term
43 Diopters
Definition
The average cornea has a refractive power of approximately:
Term
Epithelium
Definition
That layer of the cornea which is highly regenerative is:
Term
Rods
Definition
Night vision is chiefly a function of the:
Term
Esophoria
Definition
tendency of the visual axis to deviate inward while the eyes are in a position of rest is known as:
Term
hyperopic
Definition
A "farsighted" eye is
Term
diplopia
Definition
The term used to indicate "double vision" is
Term
presbyopia
Definition
The condition in which the ability to accommodate for near vision becomes inadequate because of loss of elasticity of the crystalline lens is called
Term
amblyopia
Definition
When there is a loss of vision without any apparent disease of the eye it is known as:
Term
astigmatism
Definition
A refractive error in which the rays of light do not come to a single point of focus is called:
Term
cataract
Definition
The condition in which the crystalline lens of the eye gradually loses its transparancy with consequent loss of visual acuity is known as
Term
glaucoma
Definition
An ocular disease having as its primary characteristic a sustained increase in intraocular pressure.
Term
anterior chamber
Definition
The space between the back of the iris and the front of the lens which is filled with aqueous is the
Term
hyperphoria
Definition
A tendency of one eye to deviate upward is:
Term
cones
Definition
The photosensitive receptors of the retina which are responsible for sharp visual acuity and   color perception are the:
Term
the stroma
Definition
The layer of the cornea which comprises ninety percent of its thickness is:
Term
anisometropia
Definition
A condition in which the refractive error of one eye significantly differs from   that of the other and where both eyes have the same sign (i.e. both eyes are myopic or hyperopic) is known as:
Term
compound hyperopic astigmatism
Definition
The refractive error which results in two points of focus falling behind the retina is:
Term
irregular astigmatism
Definition
The refractive condition caused by a damaged cornea so that rays of light come to many focal points on the retina is known as
Term
vitreous humor
Definition
The transparent, colorless mass of soft, gelatinous material which fills the eyeball behind the lens is the
Term
1.42
Definition
The index of refraction of the crystalline lens is
Term
1.37
Definition
The cornea has an index of refraction of
Term
Visable Light
Definition
That portion of the electromagnetic spectrum to which the photosensitive receptors of the retina respond.
Term
390 nm - 750 nm
Definition
Visable Light
Term
nm nanometer
Definition
Waves of the visual spectrum are measured in billionths of a meter.
Term
Corpuscular Theory
Definition
Newton, photons (particles) travel from source
Term
Wave theory
Definition
light as moving in waves
Term
Wavelength
Definition
The distance from the crest of one wave to the crest of another.
Term
Frequency
Definition
he number of times the crest or trough of a wave passes a point in space in a given unit of time
Term
Denser material
Definition
the more the light is slowed down and the more it is deviated from its original course.
Term
Index of Refraction
Definition
The density of the material
Term
Index of Refraction
Definition
divide the speed of light in air by the speed of light in that material
Term
Index of Refraction
Definition
n = speed of light in air / speed of light in material
Term
186000
Definition
speed of light in air
Term
25.4 mm
Definition
One inch
Term
one meter (m)
Definition
39.7 in,
Term
1 meter
Definition
10 dm 100 cm 1000 mm 1 billion nanometers
Term
350 - 750 nm
Definition
Visable Light
Term
290-390 nm
Definition
UV light
Term
750 - 1400 nm
Definition
short infrared light
Term
Wavelength
Definition
The distance from the crest of one wave to the crest of another
Term
Frequency
Definition
The number of times the crest or trough of a wave passes a point in space in a given unit of time.
Term
1.53
Definition
The standard index of refraction used in the optical industry
Term
1 prism diopter
Definition
This may be expressed mathematically as: 1 cm/1m
Term
D=1/f or f=1/D
Definition
where D = power of the lens in diopters and f = focal length in meters.
Term
Shorter
Definition
The stronger the power, the ____ the focal length
Term
f=0.133 m
Definition
D= -7.50 f=1/D f=1/-7.50
Term
f=0.510 m
Definition
D= -10.00 f=1/D f=1/-10.00
Term
D=+4.50 D
Definition
f=+0.22m D=1/f D=1/0.222 m
Term
D=-1.75 D
Definition
f=-571m D=1/f D=1/-571 m
Term
Prentice's Rule
Definition
The power of the prism is equal to the power of the lens in diopters times the amount of decentration in mm divided by 10.
Term
Prism diopters =
Definition
Fxdec/10 = power of lens in dioptyers x dist in mm from oc / 10
Term
In
Definition
When the optical centers of a pair of plus lenses are positioned narrower than the PD, it produces prism base___
Term
Out
Definition
When the optical centers of a pair of minus lenses are positioned narrower than the PD, it produces prism base
Term
Down
Definition
When a patient looks through a plus lens above the optical center, it produces prism base_
Term
down
Definition
When a patient looks through a minus lens below the optical center, produces prism base_
Term
1
Definition
How much prism is induced 5 mm away from the optical center of a   +2.00 diopter lens?
Term
0.25
Definition
How much prism is induced 10 mm away from the optical center of      –0.25 diopter lens?
Term
3.2
Definition
How much prism is induced 2 mm away from the optical center of a    +16.00 diopter lens?
Term
.9 Base Out
Definition
he optical centers are positioned 61 mm apart. The work order indicates the patient’s PD measures 64 mm and the prescription calls for -3.00 spheres in each eye. How much total prism is induced and in which direction is the base?
Term
1.45 Base out
Definition
A patient’s prescription calls for OD: +4.75 OS: +2.50. The optical      centers of the finished spectacles are found to be positioned 4 mm too wide. How much total prism is induced and in which direction is the base?
Term
flint glass
Definition
The index of refraction is lowest in:
Term
39.37 in
Definition
One meter is equal to______ inches.
Term
200
Definition
Two meters equal ______centimeters.
Term
186,000 m per sec
Definition
The speed of light in air is approximately:
Term
390-750 nm
Definition
The range of wavelengths which are perceived as visible light can vary with the individual, it is generally understood to lie between
Term
wavelength
Definition
The distance between the crests of two waves is called the:
Term
Prentice's Rule
Definition
the formula to calculate the magnitude of the prism
Term
Radius of curvature
Definition
the distance from the geometric center of the circle to its periphery where the line is drawn
Term
larger
Definition
As the radius of curvature becomes longer the circle gets
Term
flatter
Definition
As the circle gets larger, its curve gets
Term
less
Definition
as the curve gets flatter on a lens, the power in diopters of that surface becomes
Term
Accommodation
Definition
Focusing of the eye on a near object through relaxation of the ciliary muscle and thickening of the lens.
Term
Amblyopia
Definition
The loss of vision without any apparent disease of the eye.
Term
Ametropia
Definition
A refractive error in which the eye, when in a state of rest, does not focus the image of an object upon the retina
Term
Aniseikonia
Definition
A condition in which the ocular image of an object as seen by one eye differs so much in size or shape from that seen by the other eye that the two images cannot be fused into a single impression.
Term
Anisometropia
Definition
A condition in which the refractive error of one eye significantly differs from that of the other
Term
Antimetropia
Definition
The refractive condition whereby the signs in each eye are opposite
Term
Aphakia
Definition
An absence of the crystalline lens of the eye.
Term
Aqueous humor
Definition
The clear watery fluid that fills the anterior and posterior chambers within the front part of the eye.
Term
Astigmatism
Definition
A refractive error that prevents the light rays from coming to a single focus on the retina because of different degrees of refraction in the various meridians of the eye.
Term
Cataract
Definition
A condition in which the crystalline lens of the eye, or its
Term
Choroid
Definition
The vascular intermediate coat that furnishes nourishment to other parts of the eyeball.
Term
Ciliary body
Definition
That portion of the vascular coat between the iris and the choroid. It consists of ciliary processes and the ciliary muscle.
Term
Compound hyperopic astigmatism
Definition
The refractive error which results in two points of focus falling behind the retina.
Term
Compound myopic astigmatism
Definition
The refractive error which results in two points of focus falling in front of the retina.
Term
Cornea
Definition
The clear transparent portion of the outer coat of the eyeball forming the covering of the aqueous chamber.
Term
Crystalline Lens
Definition
A transparent colorless body suspended in the front part of the eyeball, between the aqueous and the vitreous, the function of which is to bring the rays of light to a focus on the retina.
Term
Diplopia
Definition
The seeing of one object as two.
Term
Emmetropia
Definition
The refractive condition of the normal eye. When the eye is at rest, the image of distant objects is brought to a focus on the retina.
Term
Fovea
Definition
A small depression in the retina at the back of the eye
Term
Fusion
Definition
The power of coordination by which the images received by the two eyes become a single image.
Term
Glaucoma
Definition
An ocular disease having as its primary characteristic a sustained increase in intraocular pressure that the eye cannot withstand without damage to its structure or impairment of its function.
Term
Hyperopia
Definition
A refractive error in which, because the eyeball is short or the refractive power of the lens is weak, the point of focus for rays of light from distant objects falls behind the retina
Term
Iris
Definition
The colored circular membrane suspended behind the cornea and immediately in front of the lens. The iris regulates the amount of light entering the eye by changing the size of the pupil.
Term
Irregular Astigmatism
Definition
A refractive condition caused by a cornea which is damaged and irregular so that rays of light come to many focal points on the retina
Term
Iseikonic Lenses
Definition
Spectacle lenses specially designed to manipulate image size when dissimilar sizes makes it difficult or impossible for fusion to occur
Term
Macula
Definition
The small area of the retina that surrounds the fovea and that with the fovea, comprises the area of the retina that gives distinct vision.
Term
Mixed Astigmatism
Definition
The refractive condition in which light comes to two points of focus where one point is in front of the retina, and the other is behind the retina.
Term
Myopia (nearsightedness)
Definition
A refractive error in which the eyeball is too long in relation to its focusing power
Term
Oculus Dexter (O.D.)
Definition
The right eye.
Term
Oculus Sinister (O.S.)
Definition
Left eye
Term
Oculus Uterque (O.U.)
Definition
Each eye.
Term
Optic Nerve
Definition
The special nerve of the sense of sight that carries impulses from the retina to the brain.
Term
Phoria
Definition
A root word denoting a latent deviation in which the eyes have a constant tendency to turn from the normal position for binocular vision
Term
Presbyopia
Definition
A gradual lessening of the power of accommodation due to a physiologic change that becomes noticeable about the age of 40 years.
Term
Ptosis Crutch
Definition
A small spring wire attached nasally to a spectacle frame to lift a drooping lid.
Term
Pupil
Definition
The central opening of the iris through which light is permitted to enter the eye.
Term
Regular Astigmatism
Definition
A refractive condition in which rays of light come to two focal points and is correctable by cylinders.
Term
Retina
Definition
Innermost coat of the eye, formed of sensitive nerve elements and connected with the optic nerve.
Term
Rods and Cones
Definition
Two different kinds of cells that form a layer of the retina and act as light-receiving media. Cones are concerned with visual acuity and color discrimination
Term
Sclera
Definition
The white part of the eye
Term
Scotoma
Definition
A blind area of reduced vision in the visual field.
Term
Simple hyperopic astigmatism
Definition
The refractive condition where one point of focus falls on the retina and the other point of focus falls behind the retina.
Term
Simple myopic astigmatism
Definition
The refractive condition where one point of focus falls on the retina and the other point of focus falls in front of the retina.
Term
Strabismus
Definition
Failure of the two eyes to simultaneously direct their gaze at the same object because of muscle imbalance. Also known as squint.
Term
Suspensory Ligaments
Definition
The suspensory apparatus of the lens. Numerous fine tissue
Term
Tropia
Definition
A root word denoting an obvious deviation from normal of the axis of the eyes
Term
Vitreous Humor
Definition
The transparent, colorless mass of soft, gelatinous material filling the eyeball behind the lens.
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