ABO advance study guide
Comprehensive Questions (Frequently
Tested) with Verified Answers Graded A+
When taking seg height measurements, which of the following situations could result in a
parallax error? - Answer: Patient sitting/ dispenser standing erect
Which of the following is not significant in identifying the problem of vertical imbalance? -
Answer: Patient's age
Which of the following elements is NOT critical when determining vertical imbalance? - Answer:
Lens power in the 180 degree meridian
A prism will displace the object being viewed towards its ________. - Answer: Apex
A prism will bend light towards its _______. - Answer: Base
When dealing with problems of vertical imbalance which is the critical meridian of total lens? -
Answer: 90
Which of the following prescriptions would pose the greatest prismatic imbalance at a reading
depth of 10mm? - Answer: OD +2.50
OS -0.25 +2.50 x 090
A plus lens moved downward from the primary position will result in: - Answer: Base down
prismatic effect
,What is a hereditary pigmentary degeneration of the retina called which results in gradual loss
of peripheral vision? - Answer: Retinitis pigmentosa
What is ocular hypertension? - Answer: Elevation of pressure in the eye above the range
considered with an detectable changes in vision or damage to the structure of the eye.
or
Eye pressure can be elevated and cause damage in some eyes, but no damage in others.
Which of the following statements is false regarding corneal ulcers? Corneal ulcers can be
________. - Answer: of little concern
Approximately what percentage of humans have some alterations in lens transparency after age
65? - Answer: 60%
What type of cataract is a fully developed opacity of the lens with fluid generation and swelling
of the lens volume? - Answer: Hypermature
Which of the following statements is false regarding cataracts? - Answer: Cataracts will only
form in the nucleus of the lens.
________ is the condition in which both eyes have equal refractive power. - Answer:
Insometropia
Irregular astigmatism occurs when the principal meridians are not uniform along a major
meridian and not uniform along a meridian. They are found at some place other than 90 degree
apart. Irregular astigmatism is commonly caused by trauma surgery, or corneal dystrophy. TRUE
or FALSE - Answer: True
,In poor light, a person sees red light better than blue, which is why the ocular system tends to
be more myopic, i.e. twilight myopia.
TRUE or FALSE - Answer: True
_______ are _____ cells that detect motion within a field. - Answer: Rods-Long
The crystalline lens is the same size at birth as in an adult, however, it adds cell layers
throughout life, packing them in which makes the crystalline lens harder and is one of the
causes of presbyopia. TRUE or FALSE - Answer: False
The triangular structure between the choroid and root of the iris, containing the ciliary
epithelium, stroma, and ciliary muscle is the: - Answer: Ciliary body
There are 5 layers of the cornea. They are: - Answer: From most anterior to posterior.
Epithelium-Bowman's Layer- Stroma- Descemet membrane- Endothelium
The refractive index of the cornea is: - Answer: 1.376
The most powerful refracting medium of the eyes optical system is the cornea. There are five
layers of the cornea, each having a unique purpose and cell structure. One of the requirements
of clear vision is that the cornea ________. - Answer: must remain transparent and must have
regular cell structures of all layers.
Polarized filters are made by stretching thin sheets of __________ in one meridian. - Answer:
Polyvinyl alcohol
Visible glare can be dangerous because it can not only wash out colors, but in some instances,
can cause _________. - Answer: Photokeratitis
, Features and benefits of Trivex include __________. - Answer: Superior optics
Impact Resistant
Ultra-lightweight
What is the index of refraction of Trivex? - Answer: 1.53
What is the index refraction of polycarbonate? - Answer: 1.59
What company introduced CR-39 lenses? - Answer: PPG industries
__________ are generally inorganic materials (metals or minerals) that are vacuum deposited to
add color on glass lenses to give a uniform density of color on the lenses. - Answer: Vacuum
color coating
Glare is of more concern to which wearer? - Answer: Cataract patients
_______ is better than ______ for improving contrast? - Answer: Green-Gray
_______ added to any color increases contrast. - Answer: Yellow
Although this may be the most popular color for sun lenses, it is not recommended for patients
with emerging cataracts. - Answer: Gray
Given a high plus or high minus RX, which lens material would offer the best choice for uniform
density in sun lenses? - Answer: CR-39 & Trivex
Comprehensive Questions (Frequently
Tested) with Verified Answers Graded A+
When taking seg height measurements, which of the following situations could result in a
parallax error? - Answer: Patient sitting/ dispenser standing erect
Which of the following is not significant in identifying the problem of vertical imbalance? -
Answer: Patient's age
Which of the following elements is NOT critical when determining vertical imbalance? - Answer:
Lens power in the 180 degree meridian
A prism will displace the object being viewed towards its ________. - Answer: Apex
A prism will bend light towards its _______. - Answer: Base
When dealing with problems of vertical imbalance which is the critical meridian of total lens? -
Answer: 90
Which of the following prescriptions would pose the greatest prismatic imbalance at a reading
depth of 10mm? - Answer: OD +2.50
OS -0.25 +2.50 x 090
A plus lens moved downward from the primary position will result in: - Answer: Base down
prismatic effect
,What is a hereditary pigmentary degeneration of the retina called which results in gradual loss
of peripheral vision? - Answer: Retinitis pigmentosa
What is ocular hypertension? - Answer: Elevation of pressure in the eye above the range
considered with an detectable changes in vision or damage to the structure of the eye.
or
Eye pressure can be elevated and cause damage in some eyes, but no damage in others.
Which of the following statements is false regarding corneal ulcers? Corneal ulcers can be
________. - Answer: of little concern
Approximately what percentage of humans have some alterations in lens transparency after age
65? - Answer: 60%
What type of cataract is a fully developed opacity of the lens with fluid generation and swelling
of the lens volume? - Answer: Hypermature
Which of the following statements is false regarding cataracts? - Answer: Cataracts will only
form in the nucleus of the lens.
________ is the condition in which both eyes have equal refractive power. - Answer:
Insometropia
Irregular astigmatism occurs when the principal meridians are not uniform along a major
meridian and not uniform along a meridian. They are found at some place other than 90 degree
apart. Irregular astigmatism is commonly caused by trauma surgery, or corneal dystrophy. TRUE
or FALSE - Answer: True
,In poor light, a person sees red light better than blue, which is why the ocular system tends to
be more myopic, i.e. twilight myopia.
TRUE or FALSE - Answer: True
_______ are _____ cells that detect motion within a field. - Answer: Rods-Long
The crystalline lens is the same size at birth as in an adult, however, it adds cell layers
throughout life, packing them in which makes the crystalline lens harder and is one of the
causes of presbyopia. TRUE or FALSE - Answer: False
The triangular structure between the choroid and root of the iris, containing the ciliary
epithelium, stroma, and ciliary muscle is the: - Answer: Ciliary body
There are 5 layers of the cornea. They are: - Answer: From most anterior to posterior.
Epithelium-Bowman's Layer- Stroma- Descemet membrane- Endothelium
The refractive index of the cornea is: - Answer: 1.376
The most powerful refracting medium of the eyes optical system is the cornea. There are five
layers of the cornea, each having a unique purpose and cell structure. One of the requirements
of clear vision is that the cornea ________. - Answer: must remain transparent and must have
regular cell structures of all layers.
Polarized filters are made by stretching thin sheets of __________ in one meridian. - Answer:
Polyvinyl alcohol
Visible glare can be dangerous because it can not only wash out colors, but in some instances,
can cause _________. - Answer: Photokeratitis
, Features and benefits of Trivex include __________. - Answer: Superior optics
Impact Resistant
Ultra-lightweight
What is the index of refraction of Trivex? - Answer: 1.53
What is the index refraction of polycarbonate? - Answer: 1.59
What company introduced CR-39 lenses? - Answer: PPG industries
__________ are generally inorganic materials (metals or minerals) that are vacuum deposited to
add color on glass lenses to give a uniform density of color on the lenses. - Answer: Vacuum
color coating
Glare is of more concern to which wearer? - Answer: Cataract patients
_______ is better than ______ for improving contrast? - Answer: Green-Gray
_______ added to any color increases contrast. - Answer: Yellow
Although this may be the most popular color for sun lenses, it is not recommended for patients
with emerging cataracts. - Answer: Gray
Given a high plus or high minus RX, which lens material would offer the best choice for uniform
density in sun lenses? - Answer: CR-39 & Trivex
