What is the Landolt ring chart?
A visual acuity test chart that uses rings with a gap to determine the direction of the gap, allowing for assessment of visual acuity.
What does a visual acuity of 20/200 to 20/400 indicate?
A visual acuity of 20/200 to 20/400 indicates severe low vision, which is considered legal blindness by US definition. Individuals at this level can generally orient and move but may have difficulty with traffic signs and reading without high-power magnifiers.
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p.9
Testing Conventions and Materials

What is the Landolt ring chart?

A visual acuity test chart that uses rings with a gap to determine the direction of the gap, allowing for assessment of visual acuity.

p.12
Visual Impairment

What does a visual acuity of 20/200 to 20/400 indicate?

A visual acuity of 20/200 to 20/400 indicates severe low vision, which is considered legal blindness by US definition. Individuals at this level can generally orient and move but may have difficulty with traffic signs and reading without high-power magnifiers.

p.9
Variables in Acuity Measurements

What is myopia?

A refractive error where distant objects appear blurry while close objects can be seen clearly, often referred to as nearsightedness.

p.12
Visual Impairment

What is the significance of a visual acuity of less than CF 4 ft?

A visual acuity of less than CF 4 ft indicates nearly total blindness, where vision is unreliable except under ideal circumstances, and individuals must rely on non-visual devices.

p.11
Visual Acuity Measurement

What is the definition of Legal Blindness?

Legal blindness is defined as severe visual impairment in both eyes, which is often used to determine eligibility for disability benefits.

p.14
Contrast Sensitivity and Other Visual Functions

What are pseudoisochromatic color plates?

Pseudoisochromatic color plates are a set of multicolored dot patterns used to evaluate color vision, where patients with normal color vision can easily detect specific numbers and figures embedded in the pattern, while those with impaired color vision may not.

p.14
Visual Acuity Measurement

What are some pitfalls to avoid in visual acuity measurement?

Pitfalls include ensuring that all lenses, projectors, and charts are clean, paying attention to distances and calibrations for each type of acuity screen, avoiding glare on the viewing chart or in patients' eyes, and using appropriate tests for the patient's abilities.

p.17
Near Acuity Testing

What is Near Point of Convergence (NPC)?

The NPC is the point where a single image can no longer be maintained, noted when the image doubles or one eye deviates from the fixation target.

p.16
Visual Acuity Measurement

What is the purpose of using habitual correction during visual acuity tests?

Using habitual correction allows the patient to see as clearly as possible during the test, providing a more accurate assessment of their visual acuity.

p.15
Visual Acuity Measurement

What is the significance of recording acuity values for each eye separately?

Recording acuity values for each eye separately allows for a detailed assessment of visual function and helps identify any discrepancies in vision between the two eyes.

p.16
Near Acuity Testing

What is the procedure for Testing Near Visual Acuity?

The procedure involves the patient wearing their habitual corrective lens, holding a near card at a specified distance, occluding one eye at a time, and reading the smallest legible characters, with acuity values recorded for each eye and binocularly.

p.16
Testing Conventions and Materials

What is the importance of occluding the eye not being tested?

Occluding the eye not being tested helps to isolate the visual function of the eye being assessed, ensuring accurate measurement of visual acuity.

p.9
Variables in Acuity Measurements

What is convergence insufficiency?

A condition where the eyes do not work together properly while focusing on a nearby object, affecting binocular visual acuity.

p.15
Snellen Acuity Notation

What does the notation '20/40 − 2' indicate in visual acuity testing?

'20/40 − 2' indicates that the patient was able to read the 20/40 line but missed 2 letters on that line.

p.15
Visual Acuity Measurement

What is the purpose of retesting acuity with both eyes simultaneously?

Retesting acuity with both eyes simultaneously helps to assess the combined visual function and can provide a more comprehensive understanding of the patient's overall visual acuity.

p.8
Acuity Tests for Patients with Special Needs

What are some testing methods for toddlers and preliterate children?

Testing methods for toddlers and preliterate children include picture charts, Lea symbols, the Landolt C or tumbling E test, and the HOTV chart.

p.4
Visual Acuity Measurement

What does the abbreviation 'OU' represent in visual acuity testing?

'OU' represents 'both eyes (together)', indicating that the visual acuity measurement is for both eyes simultaneously.

p.17
Near Acuity Testing

What is Near Point of Accommodation (NPA)?

The NPA is the point (in centimeters or inches) where the patient can no longer bring the image into clear focus.

p.17
Near Acuity Testing

What is the procedure for testing Near Point of Accommodation (NPA)?

The procedure involves placing a near testing card at 16 inches from the patient, asking them to read a specific line, moving the card closer until the letters blur, and recording that distance.

p.17
Near Acuity Testing

What is the procedure for testing Near Point of Convergence (NPC)?

The procedure involves holding a target at approximately 16 inches from the patient, moving it closer until the image doubles, and observing eye convergence.

p.15
Testing Conventions and Materials

What does it mean to occlude the left eye during visual acuity testing?

To occlude the left eye means to cover it with an occluder to prevent vision, ensuring that only the right eye is tested for visual acuity.

p.10
Visual Acuity Measurement

How can tear film abnormalities affect visual acuity?

Tear film abnormalities, such as dry eye syndromes, can decrease visual acuity, but their effects can be minimized by the generous use of artificial tear preparations.

p.10
Acuity Tests for Patients with Special Needs

What is latent nystagmus?

Latent nystagmus is a condition that occurs only when one eye is occluded, causing the unoccluded eye to develop nystagmus, resulting in lower measured visual acuity compared to binocular acuity.

p.6
Near Acuity Testing

What does presbyopia refer to?

Presbyopia refers to the condition where the near point of accommodation recedes with age, making it difficult to focus on close objects.

p.6
Near Acuity Testing

What is the normal range for NPC?

The normal range for the near point of convergence (NPC) is between 6 cm and 10 cm, regardless of a person's age.

p.11
Visual Acuity Measurement

What is Visual Impairment?

Visual impairment refers to a condition where a person cannot achieve normal vision (20/20) even with optical correction such as eyeglasses or contact lenses.

p.11
Visual Acuity Measurement

What is the criterion for Severe Visual Impairment?

Severe visual impairment is characterized by corrected distance visual acuity being less than 20/160, including ranges from 20/200 to 20/400.

p.13
Acuity Tests for Patients with Special Needs

What is the crowding phenomenon in amblyopia?

The crowding phenomenon refers to the tendency of amblyopic patients to identify smaller optotypes more easily when viewed singly rather than in a line with figures on both sides.

p.13
Contrast Sensitivity and Other Visual Functions

What is glare in the context of visual function?

Glare occurs when light from a single bright source scatters across the visual field, reducing the quality of the visual image and potentially causing distorted vision.

p.14
Contrast Sensitivity and Other Visual Functions

What is the 15-hue test?

The 15-hue test, also known as the Farnsworth-Munsell D-15 test, consists of 15 pastel-colored chips that patients must arrange in a related color sequence, which is obvious to those with normal color vision but challenging for patients with color deficits.

p.5
Pinhole Acuity Test

What is the significance of a pinhole improving visual acuity by 2 lines or more?

If the pinhole improves the patient's acuity by 2 lines or more, it suggests that the patient likely has a refractive error, as the pinhole allows for better light entry without the need for refraction by the cornea or lens.

p.5
Near Acuity Testing

What factors can affect a patient's preferred reading distance during Near Acuity Testing?

A patient's preferred reading distance can vary based on the types of near activities they engage in and whether they use near spectacles.

p.10
Testing Conventions and Materials

What is the role of special lenses in astigmatism?

Corneal or lenticular astigmatism might necessitate the use of special spectacle or contact lenses to correct the visual impairment.

p.1
Snellen Acuity Notation

What does Snellen acuity measure?

Snellen acuity measures the resolving ability of the eye using targets that subtend a visual angle of 5 minutes of arc.

p.11
Visual Acuity Measurement

What is the significance of Visual Acuity in determining disability?

Visual acuity is an important factor used by examiners to estimate a patient's potential disability and to determine appropriate reading aids and distances.

p.5
Pinhole Acuity Test

What is the Pinhole Acuity Test?

The Pinhole Acuity Test is a method used to assess visual acuity by having the patient read a testing chart through a pinhole occluder, which allows only central rays of light to enter, helping to determine if reduced visual acuity is due to a refractive error.

p.5
Testing Conventions and Materials

Why is it important to use different charts or optotype sequences during visual acuity testing?

Using different charts or optotype sequences is important because patients may memorize the sequence of images they have seen multiple times, which can affect the accuracy of the test results.

p.3
Snellen Acuity Notation

What does the Snellen acuity expression represent?

The Snellen acuity expression represents the distance at which a patient can read a specific line of optotypes, with the numerator indicating the distance from the chart and the denominator indicating the size of the optotype read correctly.

p.3
Visual Acuity Measurement

How is visual acuity recorded when a patient misses letters?

Visual acuity is recorded with a superscript notation indicating the number of letters missed, for example, 20/40 − 2 if two letters are missed on the 20/40 line.

p.18
Visual Acuity Measurement

What does CF stand for in visual acuity testing?

CF stands for 'counting fingers,' which is used to record the longest distance at which a patient can accurately count fingers displayed by the examiner.

p.18
Visual Acuity Measurement

What does NLP mean in visual acuity testing?

NLP stands for 'no light perception,' indicating that the patient cannot perceive any light.

p.4
Visual Acuity Measurement

What does the abbreviation 'cc' stand for in visual acuity testing?

'cc' stands for 'with correction', indicating that corrective lenses were worn during the visual acuity test.

p.1
Measurement Notation

What is the purpose of measurement notation in visual acuity testing?

Measurement notation provides a standardized way to express visual acuity measurements, facilitating communication and documentation.

p.16
Pinhole Acuity Test

What is Pinhole Visual Acuity?

A method of testing visual acuity where the patient looks through a pinhole occluder to determine the sharpest image they can see on a distance chart.

p.9
Variables in Acuity Measurements

What is presbyopia?

A condition associated with aging that results in a gradual loss of the eye's ability to focus on nearby objects.

p.9
Variables in Acuity Measurements

What is accommodative insufficiency?

A condition where the eye has difficulty focusing on near objects due to inadequate accommodation.

p.12
Visual Impairment

What type of visual aids are suggested for profound visual impairment (20/500 to 20/1000)?

For profound visual impairment (20/500 to 20/1000), limited spot reading with visual aids is possible, and high-power magnifiers are typically required.

p.8
Visual Acuity Measurement

What is the significance of horizontal OKN by 3 months of age?

Horizontal OKN should be present by 3 months of age, indicating normal visual development and the ability to track moving objects.

p.7
Low-Vision Testing

What is the purpose of low-vision testing?

Low-vision testing aims to assess the visual capabilities of patients who cannot read the largest line on a standard visual acuity chart, often by using shorter distances or alternative methods to measure acuity.

p.11
Visual Acuity Measurement

What constitutes Profound Visual Impairment?

Profound visual impairment is defined as corrected distance visual acuity being less than 20/400, which includes ranges from 20/500 to 20/1000.

p.1
Visual Acuity Measurement

What is the smallest angle discernible for normal human vision?

One minute is the smallest angle discernible for normal human vision.

p.12
Visual Acuity Measurement

What is Amblyopia?

Amblyopia is a visual disorder characterized by a difference in optically correctable acuity of more than 2 lines between both eyes, resulting from abnormal visual input in early childhood. It is commonly referred to as 'lazy eye.'

p.12
Reading Distance: Reading Aids

What are the reading aids recommended for a visual acuity of 20/80 to 20/160?

For a visual acuity of 20/80 to 20/160, strong reading glasses or vision magnifiers are recommended, as they usually provide adequate reading ability, although this level is typically insufficient for a driving license.

p.3
Visual Acuity Measurement

What is the significance of the letter L in visual acuity testing?

The letter L is the easiest letter to recognize during visual acuity testing and can be mistaken for few letters other than the letter I, making misinterpretation of other letters, like B, less significant.

p.14
Acuity Tests for Patients with Special Needs

Why should the term 'blindness' be avoided when counseling patients with severe visual impairment?

The term 'blindness' should be avoided because most patients with severe visual impairment have some useful vision, and many demonstrate significant resourcefulness.

p.3
Standard Abbreviations

What are some common abbreviations used in visual acuity testing records?

Common abbreviations include C, S, M (central, steady, maintained fixation) and F & F (fixes and follows), which are used for preverbal or nonverbal children.

p.10
Visual Acuity Measurement

What neurologic factors can influence visual acuity testing?

Neurologic factors such as visual field defects, optic nerve lesions, pupillary abnormalities, and impairment by drugs can all influence visual acuity testing.

p.11
Visual Acuity Measurement

What visual acuity is typically required for an unrestricted driver's license?

Most states require visual acuity to be correctable to 20/40 or better in at least one eye for an unrestricted driver's license.

p.17
Acuity Tests for Patients with Special Needs

What is the recommended approach for testing acuity in patients with low vision?

For patients unable to resolve the largest optotype, they should be positioned 10 feet from a well-illuminated test chart, with the eye not being tested occluded, and the testing distance halved until they can identify half the optotypes on a line.

p.10
Visual Acuity Measurement

What is the effect of dirty lenses on visual acuity?

Dirty lenses of any kind, whether trial lenses, phoropter lenses, eyeglass lenses, or contact lenses, will decrease acuity, resulting in falsely low measurements.

p.9
Variables in Acuity Measurements

What is the effect of patient fatigue on acuity measurements?

Patient fatigue or boredom can affect acuity measurements, making it difficult to assess their true visual acuity.

p.10
Visual Acuity Measurement

What are the implications of motility defects on visual acuity measurement?

Motility defects such as nystagmus or other movement disorders can interfere with the ability to align the fovea on the object of regard, leading to lower acuity measurements.

p.6
Near Acuity Testing

What is the near point of convergence (NPC)?

The near point of convergence (NPC) is the nearest point to which both eyes can converge and still maintain a single image.

p.18
Visual Acuity Measurement

What is the significance of light perception (LP) in visual acuity testing?

LP indicates that the patient can perceive light, and it can be further specified as 'LP with projection' or 'LP without projection' based on the patient's ability to identify the direction of the light.

p.18
Testing Conventions and Materials

What should be used to attract an infant's attention during visual testing?

A small toy or other sight-stimulating object that does not produce sound, held about 1–2 feet from the infant's face.

p.4
Testing Conventions and Materials

What is the purpose of using an occluder during a visual acuity test?

An occluder is used to cover the eye that is not being tested, ensuring that only one eye is evaluated at a time for accurate measurement.

p.4
Near Acuity Testing

What does 'NPA' stand for in visual acuity notations?

'NPA' stands for 'Near Point of Accommodation', which refers to the closest point at which the eye can focus on an object.

p.13
Acuity Tests for Patients with Special Needs

What is unilateral amblyopia?

Unilateral amblyopia is a condition where one eye has reduced vision due to causes such as anisometropia, strabismus, or unilateral media opacities like congenital cataracts.

p.13
Contrast Sensitivity and Other Visual Functions

What does contrast sensitivity measure?

Contrast sensitivity measures the ability to discern relative darkness and brightness, as well as the ability to see details, edges, and borders of images.

p.13
Contrast Sensitivity and Other Visual Functions

What are common causes of color vision differences between two eyes?

Color vision differences between two eyes may indicate optic nerve or retinal disease, with common abnormalities including X-linked congenital red-green deficiencies.

p.3
Testing Conventions and Materials

What are the characteristics of the HOTV optotypes used in visual acuity testing?

The HOTV optotypes are symmetric, useful for matching, and particularly effective for nonverbal or illiterate patients, making them suitable for testing young children.

p.8
Testing Conventions and Materials

What is Optokinetic Nystagmus (OKN)?

Optokinetic Nystagmus (OKN) is a reflexive eye movement that can be elicited by moving a regularly striped object in front of a viewer, indicating the ability to discriminate detail.

p.15
Pinhole Acuity Test

What is the role of the pinhole test in visual acuity assessment?

The pinhole test is used to recheck visual acuity when it is worse than 20/20, helping to determine if the reduced acuity is due to refractive error or other factors.

p.18
Visual Acuity Measurement

What does HM indicate in visual acuity testing?

HM stands for 'hand motion,' which is recorded when a patient can detect the examiner's hand movement at a specified distance.

p.1
Visual Acuity Measurement

What is visual acuity?

Visual acuity refers to an angular measurement that relates testing distance to the minimal object size resolvable at that distance.

p.11
Visual Acuity Measurement

What defines Moderate Visual Impairment?

Moderate visual impairment is defined as corrected distance visual acuity (best-corrected VA) being less than 20/60, which includes ranges from 20/70 to 20/160.

p.1
Snellen Acuity Notation

What does a 20/20 visual acuity indicate?

A 20/20 visual acuity is considered normal visual acuity, meaning the individual can see at 20 feet what should normally be seen at that distance.

p.16
Pinhole Acuity Test

What does the abbreviation PH signify in visual acuity testing?

PH signifies the acuity obtained using the pinhole test, indicating that the measurement was taken while the patient was looking through a pinhole occluder.

p.15
Visual Acuity Measurement

What is the Testing Distance Visual Acuity protocol?

The Testing Distance Visual Acuity protocol involves asking the patient to stand or sit at a designated distance (ideally 20 feet) from a well-illuminated wall chart, occluding one eye, and having the patient identify letters or objects on successively smaller optotypes until a certain threshold is reached.

p.9
Variables in Acuity Measurements

How do lighting conditions affect acuity tests?

Lighting conditions must remain equivalent for acuity tests to be comparable, as variations can influence visibility and accuracy of measurements.

p.14
Acuity Tests for Patients with Special Needs

How should one interact with patients who have low vision or are blind?

When interacting with patients who have low vision or are blind, it is important to alert them to your movements beforehand, offer an arm for guidance without grabbing, and use a demeanor and testing approach appropriate for their age.

p.6
Near Acuity Testing

What is the near point of accommodation (NPA)?

The near point of accommodation (NPA) is the nearest point at which the eye can focus to form a clear image on the retina.

p.8
Contrast Sensitivity and Other Visual Functions

What is the crowding phenomenon in visual acuity testing?

The crowding phenomenon refers to the effect where the presence of nearby letters or objects makes it more difficult for a patient to identify a target, enhancing sensitivity for detecting amblyopia.

p.2
Types of Visual Acuity Notations

What is logMAR notation?

A visual acuity notation that expresses visual acuity as the logarithm of the minimum angle of resolution, with acuity of 20/20 having a logMAR value of 0.

p.6
Near Acuity Testing

What is the purpose of the Prince or RAF rule in vision testing?

The Prince or RAF rule is used to convert measurements of the near point of accommodation (NPA) expressed in meters into diopters.

p.4
Pinhole Acuity Test

What is the purpose of the Pinhole Acuity Test?

The Pinhole Acuity Test is used to determine if a patient's vision can improve with pinhole occlusion, helping to differentiate between refractive errors and other vision issues.

p.5
Testing Conventions and Materials

What should be done before conducting a visual acuity examination?

Before conducting a visual acuity examination, it is important to determine if the patient is familiar with the optotypes being used and to choose the appropriate chart based on the patient's comfort with letters or numbers.

p.5
Near Acuity Testing

What is assessed during the Near Acuity Test?

The Near Acuity Test assesses a patient's ability to see clearly at a normal reading distance, taking into account their preferred reading distance and any near spectacles they may use.

p.2
Types of Visual Acuity Notations

What does decimal notation represent in visual acuity?

A conversion of the Snellen fraction to a decimal format, where Snellen 20/20 equals decimal 1.0, Snellen 20/30 equals decimal 0.7, and Snellen 20/40 equals decimal 0.5.

p.6
Types of Visual Acuity Notations

What is Jaeger notation?

Jaeger notation, also referred to as number acuity, is a system used to indicate near visual acuity on test cards.

p.7
Acuity Tests for Patients with Special Needs

What is fixation preference testing?

Fixation preference testing is a method used to detect amblyopia in preverbal children by observing which eye the child prefers to use when both eyes are tested separately.

p.9
Variables in Acuity Measurements

What impact does chart cleanliness have on visual acuity testing?

If a chart is not kept clean, smaller letters become more difficult to identify, potentially leading to falsely low acuity measurements.

p.6
Near Acuity Testing

What is a Rosenbaum pocket vision screener?

A Rosenbaum pocket vision screener is a tool used to test near visual acuity, often utilized in clinical settings.

p.4
Visual Acuity Measurement

What is the Distance Acuity Test?

The Distance Acuity Test is a vision test performed to measure a patient's ability to see at a distance, typically conducted with and without corrective lenses.

p.2
Types of Visual Acuity Notations

What is the Jaeger (J) notation used for?

A method to express near visual acuity by assigning arbitrary numbers to Snellen equivalent figures.

p.4
Visual Acuity Measurement

What does the abbreviation 'sc' indicate in visual acuity testing?

'sc' indicates 'without correction', meaning the visual acuity test was performed without the use of corrective lenses.

p.1
Test Targets in Visual Acuity Testing

What are optotypes in visual acuity testing?

Optotypes are targets used in visual acuity testing that subtend a visual angle on the retina, typically consisting of letters or symbols.

p.18
Snellen Acuity Notation

What is Snellen acuity designation?

A method of recording visual acuity by indicating the distance at which a patient can read a specific line on an eye chart, expressed as a fraction (e.g., 5/80).

p.2
Snellen Acuity Notation

What is the Snellen notation?

A visual acuity notation that quantifies visual discrimination of fine detail, represented as a fraction where the numerator indicates the distance at which the test is performed and the denominator indicates the distance at which a subject with unimpaired vision can read the same figure.

p.6
Near Acuity Testing

What are Allen reduced picture cards used for?

Allen reduced picture cards are used to test near visual acuity in children.

p.2
Test Targets in Visual Acuity Testing

What is an optotype?

An individual letter, number, or picture on a testing chart used in visual acuity testing.

p.11
Visual Acuity Measurement

What external factors can affect visual acuity measurement?

External factors such as patient distraction, fatigue, age, and psychological influences can affect the results of visual acuity measurements.

p.3
Acuity Tests for Patients with Special Needs

What is the Amblyopia Treatment Study (ATS) visual acuity testing protocol?

The ATS visual acuity testing protocol uses isolated HOTV optotypes surrounded by bars and is gaining acceptance for testing young children due to its high testability and excellent test-retest reliability.

p.10
Acuity Tests for Patients with Special Needs

How can visual acuity be tested in the presence of latent nystagmus?

In cases of suspected latent nystagmus, the fellow eye may be blurred using a +10.00 to +20.00 diopter lens instead of a standard occluder to obtain the best possible monocular visual acuity.

p.7
Snellen Acuity Notation

What is the Snellen fraction?

The Snellen fraction is a notation used to express visual acuity, represented as a ratio of the distance at which a patient can read a specific line on a visual acuity chart to the distance at which a person with normal vision can read the same line.

p.1
Snellen Acuity Notation

What is the significance of the number in the denominator of Snellen notation?

The number in the denominator represents the distance at which the target subtends a visual angle of 5 minutes of arc.

p.7
Testing Conventions and Materials

What are Teller acuity cards?

Teller acuity cards are large photographic plates used to estimate visual acuity in infants, featuring line gratings that become progressively smaller, allowing the examiner to determine the baby's direction of gaze.

p.7
Visual Acuity Measurement

What is the significance of the blink response in newborns?

A consistent blink response to a bright light, even through closed eyelids, is an indicator of normal visual function in newborns.

p.8
Testing Conventions and Materials

Why might children prefer different types of visual acuity charts?

Children may prefer different types of visual acuity charts because some respond better to numbers while others prefer letters, and their engagement can affect testing accuracy.

p.18
Testing Conventions and Materials

What is the purpose of testing an infant's fixing and following behavior?

To assess the infant's visual tracking and fixation abilities by observing their eye movements in response to a visually stimulating object.

p.6
Acuity Tests for Patients with Special Needs

Why do patients with extremely low vision require special testing?

Patients with extremely low vision, including infants, toddlers, illiterate adults, and nonverbal patients, require special testing methods and attention to accurately assess their visual acuity.

p.4
Testing Conventions and Materials

What is the significance of testing the right eye first in visual acuity testing?

Testing the right eye first is a convention in visual acuity testing to maintain consistency and avoid confusion in the testing routine.

p.8
Testing Procedures for Distance and Near Acuity

Fine oscillatory movements with the slow phase going in the direction of the stripes indicate that the baby has a potential for discriminating detail of at least the width of the ___.

stripe

p.2
Types of Visual Acuity Notations

The Jaeger (J) notation is used to express ___ visual acuity.

near

p.2
Test Targets and Optotypes

Each individual letter, number, or picture on a testing chart is referred to as an ___.

optotype

p.1
Visual Acuity Measurement

The term visual acuity refers to an angular measurement that relates testing distance to the minimal object size resolvable at that ___.

distance

p.13
Testing Procedures for Distance and Near Acuity

Contrast sensitivity refers to the ability to discern relative darkness and brightness and the ability to see ___, edges, and borders of images.

details

p.5
Testing Procedures for Distance and Near Acuity

Before the visual acuity test begins, it is important to determine if the patient is familiar with the ___ being used.

optotypes

p.15
Testing Procedures for Distance and Near Acuity

If a patient misses half or fewer than half the letters on the smallest readable line, record how many letters were ___.

missed

p.1
Visual Acuity Measurement

The smallest angle discernible for normal human vision is ___ minute.

1

p.17
Testing Procedures for Distance and Near Acuity

For patients with low vision, if they cannot resolve the largest optotype, they should stand or sit ___ feet from the test chart.

10

p.5
Testing Procedures for Distance and Near Acuity

If the patient prefers ___, use that chart for the visual acuity test.

numbers

p.14
Testing Procedures for Distance and Near Acuity

It is important to ensure that all lenses, projectors, and charts are ___.

clean

p.5
Pinhole Acuity Testing

If the pinhole improves the patient’s acuity by ___ lines or more, it is likely that a refractive error exists.

2

p.18
Snellen Acuity Notation

Record the acuity value for each eye separately, with correction and without correction, as would be done for standard distance acuity testing, recording the distance at which the patient successfully reads the chart as the numerator of the ___ acuity designation.

Snellen

p.5
Pinhole Acuity Testing

A pinhole no more than ___ mm in diameter should be used for testing.

2.4

p.4
Testing Procedures for Distance and Near Acuity

The two basic types of vision testing are ___ and ___ visual acuity tests.

distance, near

p.10
Amblyopia and Visual Impairment

Patients with neurologic impairments may experience motility problems or central nervous system ___ that can influence acuity measurement.

abnormalities

p.17
Testing Procedures for Distance and Near Acuity

The NPA is defined as the point where the patient can no longer bring the image into ___ focus.

clear

p.12
Visual Impairment

Severe low vision, defined as legal blindness in the US, ranges from ___ to ___.

20/200, 20/400

p.15
Testing Procedures for Distance and Near Acuity

Patients should identify letters or numbers on successively smaller optotypes from ___ to ___.

left, right

p.4
Visual Acuity Measurement

The abbreviation HM stands for ___ motion.

Hand

p.9
Testing Procedures for Distance and Near Acuity

When testing visual acuity, you can ask the child which direction the legs of the letter are pointing—___, to the floor, to me, or to Mommy/Daddy?

to the ceiling

p.6
Testing Procedures for Distance and Near Acuity

To test near visual acuity, a ___ pocket vision screener or a Lebensohn chart should be used.

Rosenbaum

p.3
Visual Acuity Measurement

The easiest letter to recognize is ___, which can be mistaken for few letters other than the letter I.

L

p.9
Variables in Acuity Measurements

Falsely high or low acuity measurements can occur due to ___ or ___ conditions.

external, internal

p.16
Testing Procedures for Distance and Near Acuity

In the near visual acuity test, the patient is asked to occlude one eye and read the line with the smallest characters that are ___.

legible

p.6
Testing Procedures for Distance and Near Acuity

The near test card shows numeric notations alongside each line of ___ .

optotypes

p.15
Testing Procedures for Distance and Near Acuity

When occluding the left eye, ensure that the occluder does not ___ against the eye.

touch or press

p.8
Amblyopia and Visual Impairment

Crowding bars may be used to induce the ___ phenomenon, making the test more sensitive for amblyopia.

crowding

p.13
Amblyopia and Visual Impairment

Color vision differences between two eyes may indicate ___ nerve or retinal disease.

optic

p.3
Visual Acuity Measurement

The letterform ___ is the hardest for patients to recognize and can be confused with an E or the number 8.

B

p.2
Types of Visual Acuity Notations

The decimal notation converts the Snellen fraction to a decimal; for example, Snellen 20/20 equals decimal ___.

1.0

p.13
Amblyopia and Visual Impairment

The younger the patient, the more successful the amblyopia ___ is.

treatment

p.10
Amblyopia and Visual Impairment

Nystagmus is characterized by spontaneous oscillatory movements of the ___ .

eyes

p.4
Testing Procedures for Distance and Near Acuity

By convention, the ___ eye is tested first during a distance visual acuity test.

right

p.12
Visual Impairment

Profound visual impairment is classified as ___ to ___.

20/500, 20/1000

p.5
Testing Procedures for Distance and Near Acuity

The test for near visual acuity is usually performed at ___ inches.

16

p.16
Testing Procedures for Distance and Near Acuity

The abbreviation used to precede or follow the Snellen acuity obtained during pinhole testing is ___.

PH

p.17
Testing Procedures for Distance and Near Acuity

To test for Near Point of Accommodation (NPA), the near testing card is placed at a distance of ___ inches from the patient.

16

p.14
Testing Procedures for Distance and Near Acuity

Patients with normal color vision can easily detect specific ___ and figures in the dot pattern.

numbers

p.14
Testing Procedures for Distance and Near Acuity

The 15-hue test is also known as the ___ test.

Farnsworth-Munsell D-15

p.8
Testing Procedures for Distance and Near Acuity

Toddlers and preliterate children might be tested with a picture chart, Lea symbols, the Landolt C or ___ test.

tumbling E

p.13
Amblyopia and Visual Impairment

Causes of unilateral amblyopia include ___, strabismus, and unilateral media opacities.

anisometropia

p.8
Testing Procedures for Distance and Near Acuity

Optokinetic nystagmus (OKN) can be elicited using any regularly ___ object.

striped

p.4
Visual Acuity Measurement

The abbreviation ___ indicates that corrective lenses were worn during the visual acuity test.

cc

p.9
Variables in Acuity Measurements

The cleanliness of the projector bulb and lens affects the ___ of the letters viewed by the patient.

contrast

p.9
Variables in Acuity Measurements

Patient ___ or boredom can affect acuity measurements.

fatigue

p.10
Special Considerations for Low Vision and Children

The use of artificial tear preparations can help minimize the effects of ___ abnormalities.

tear film

p.6
Testing Procedures for Distance and Near Acuity

For children, near visual acuity can be tested with ___ reduced picture cards.

Allen

p.4
Visual Acuity Measurement

When measuring vision without corrective lenses, the abbreviation ___ is used.

sc

p.8
Special Considerations for Low Vision and Children

Vertical OKN might not be elicited until a child is approximately ___ months of age.

6

p.2
Test Targets and Optotypes

Charts with optotypes have achieved almost universal acceptance in the ___.

United States

p.13
Testing Procedures for Distance and Near Acuity

Glare occurs when light from a single bright source scatters across the visual field, reducing the quality of the visual ___.

image

p.17
Testing Procedures for Distance and Near Acuity

In low vision testing, the distance is repeatedly halved until the patient identifies half the ___ on a line.

optotypes

p.6
Special Considerations for Low Vision and Children

Patients with extremely low vision require ___ testing methods.

special

p.7
Testing Procedures for Distance and Near Acuity

If a patient cannot read the largest line of the visual acuity chart, the examiner should repeat the test at ___ distances.

shorter

p.5
Testing Procedures for Distance and Near Acuity

Near acuity testing assesses the ability to see clearly at a normal ___ distance.

reading

p.2
Snellen Acuity Notation

In the Snellen notation, the number in the ___ position indicates the distance at which a subject with unimpaired vision can read the same figure.

denominator

p.9
Variables in Acuity Measurements

Lighting conditions must remain ___ for acuity tests to be comparable.

equivalent

p.17
Testing Procedures for Distance and Near Acuity

During the NPA test, the patient is asked to state when the letters become ___.

blurred

p.13
Amblyopia and Visual Impairment

Many amblyopic patients exhibit the '___ phenomenon,' where smaller optotypes are identified more easily when viewed singly.

crowding

p.12
Amblyopia and Visual Impairment

Amblyopia is often referred to as ___ eye.

lazy

p.6
Testing Procedures for Distance and Near Acuity

The normal near point of convergence (NPC) is between ___ cm and ___ cm.

6, 10

p.4
Visual Acuity Measurement

The abbreviation NPA refers to the ___ point of accommodation.

Near

p.18
Testing Procedures for Distance and Near Acuity

If the patient is unable to resolve the largest optotypes on the chart from a distance of 2.5 feet, display 2 or more fingers of 1 hand and ask the patient to count the number of fingers displayed. Record the longest distance at which counting is done accurately; for example, ___ at 2 ft.

CF

p.18
Testing Procedures for Distance and Near Acuity

If the patient cannot detect your hand motion, shine a penlight toward the patient’s face from approximately 1 foot and turn it on and off to determine if ___ perception is present.

light

p.1
Snellen Acuity Notation

A 20/60 optotype is ___ times as big as the 20/20 optotype.

3

p.7
Amblyopia and Visual Impairment

If a child objects when one eye is covered, a difference in vision between both eyes should be strongly ___ .

suspected

p.11
Amblyopia and Visual Impairment

Legal blindness typically requires severe visual impairment in both eyes, which is often used to determine eligibility for ___ benefits.

disability

p.16
Testing Procedures for Distance and Near Acuity

During pinhole testing, the patient is instructed to use small hand or eye movements to align the pinhole to resolve the ___ image on the chart.

sharpest

p.16
Testing Procedures for Distance and Near Acuity

For near visual acuity testing, the patient should hold the test card at the distance specified on the ___ card.

test

p.10
Testing Procedures for Distance and Near Acuity

Dirty lenses, whether trial lenses, phoropter lenses, eyeglass lenses, or contact lenses, will decrease acuity and result in falsely ___ measurements.

low

p.12
Visual Acuity Measurement

Normal vision at normal reading distance is classified as ___ to ___.

20/12, 20/25

p.9
Variables in Acuity Measurements

Charts with higher contrast will be seen more easily than those with ___ contrast.

lower

p.4
Testing Procedures for Distance and Near Acuity

A variety of ___ can be used to cover the eye not being tested.

occluders

p.1
Visual Acuity Measurement

Vision is a complex human sense that includes visual acuity, visual field, and ___ sensitivity.

contrast

p.12
Amblyopia and Visual Impairment

Impaired vision in amblyopia is due to damage in the ___ and ___ that do not receive proper visual input.

lateral geniculate nucleus, visual cortex

p.1
Snellen Acuity Notation

Ophthalmologists typically use ___ acuity as a measure of the resolving ability of the eye.

Snellen

p.3
Testing Procedures for Distance and Near Acuity

Picture charts can result in over-estimation of visual acuity because the optotypes are not equally ___.

recognizable

p.11
Amblyopia and Visual Impairment

Patients with congenital nystagmus often have better visual acuity for ___ than for distance.

near

p.11
Visual Acuity Measurement

In most states, visual acuity must be correctable to ___ or better in at least one eye for an unrestricted driver's license.

20/40

p.16
Testing Procedures for Distance and Near Acuity

When recording acuity values, it is important to do so for each eye ___ in the patient’s chart.

separately

p.2
Types of Visual Acuity Notations

The logMAR notation expresses visual acuity as the logarithm of the minimum angle of ___ (log-MAR).

resolution

p.2
Types of Visual Acuity Notations

Acuity of 20/200 has a logMAR value of ___.

1.0

p.6
Testing Procedures for Distance and Near Acuity

The nearest point at which the eye can focus clearly is known as the near point of ___.

accommodation (NPA)

p.17
Testing Procedures for Distance and Near Acuity

For Near Point of Convergence (NPC) testing, the target is held at approximately ___ inches from the patient.

16

p.4
Visual Acuity Measurement

The abbreviation VA stands for ___ acuity.

Visual

p.8
Special Considerations for Low Vision and Children

If a child seems bored or hesitant with one kind of chart, it is recommended to try ___ chart.

another

p.14
Testing Procedures for Distance and Near Acuity

Avoid glare on the viewing ___ or screen.

chart

p.7
Snellen Acuity Notation

The distance at which the acuity measurement is successfully taken is used as the ___ of the Snellen fraction.

numerator

p.7
Special Considerations for Low Vision and Children

For toddlers, the examiner should allow them to sit with a ___ or familiar caretaker.

parent

p.18
Special Considerations for Low Vision and Children

For testing an infant’s fixing and following behavior, select a small toy or other attention-attracting object that stimulates sight only; do not use a ___-producing object.

sound

p.11
Visual Acuity Measurement

Severe visual impairment is defined as corrected distance VA less than ___ (including 20/200–20/400).

20/160

p.4
Testing Conventions and Materials

Which eye is conventionally tested first during a distance visual acuity test?
A) Left eye
B) Both eyes
C) Right eye
D) The eye with better vision
E) The eye with worse vision

C) Right eye
Explanation: By convention, the right eye is tested first during a distance visual acuity test, which helps maintain consistency in testing procedures.

p.15
Visual Acuity Measurement

How should the acuity measurement be recorded if a patient misses two letters on the smallest readable line?
A) 20/40
B) 20/40 - 2
C) 20/20
D) 20/200
E) 20/100

B) 20/40 - 2
Explanation: If a patient misses two letters on the smallest readable line, the acuity should be recorded as 20/40 - 2, indicating the number of letters missed.

p.16
Testing Procedures for Distance and Near Acuity

To test pinhole visual acuity, the patient should hold the pinhole occluder in front of the eye that is to be tested while wearing their ___ correction.

habitual

p.10
Testing Procedures for Distance and Near Acuity

Corneal or lenticular astigmatism might require the use of special ___ or ___ lenses.

spectacle, contact

p.12
Visual Acuity Measurement

Healthy young adults typically have vision better than ___.

20/20

p.10
Amblyopia and Visual Impairment

Visual acuity can improve when the patient maintains a head position to decrease the amplitude of the ___.

nystagmus

p.12
Amblyopia and Visual Impairment

Amblyopia results from a difference in optically correctable acuity of more than ___ lines between both eyes.

2

p.13
Amblyopia and Visual Impairment

Amblyopia can be associated with long-standing uncorrected ___ and nystagmus.

refractive errors

p.8
Special Considerations for Low Vision and Children

Horizontal OKN should be present by ___ months of age.

3

p.15
Testing Procedures for Distance and Near Acuity

The ideal testing distance for distance visual acuity is ___ feet from a well-illuminated wall chart.

20

p.10
Testing Procedures for Distance and Near Acuity

To assess latent nystagmus, the fellow eye may be blurred using a ___ to ___ diopter lens.

+10.00 to +20.00

p.6
Special Considerations for Low Vision and Children

As people age, their NPA recedes, a condition referred to as ___.

presbyopia

p.7
Low-Vision Testing

If a patient cannot read the standard chart even at close distances, the examiner can ask them to ___ the fingers held up.

count

p.5
Testing Procedures for Distance and Near Acuity

If the distance for near testing is not accurate, the measurements will not be equivalent to the ___ acuity.

distance

p.3
Snellen Acuity Notation

The distance at which the patient is placed in reference to the chart is the ___ of the Snellen expression.

numerator

p.10
Visual Acuity Measurement

How can tear film abnormalities affect visual acuity?
A) They have no effect
B) They can improve acuity
C) They can distort images
D) They can be minimized with artificial tears
E) They only affect contact lenses

D) They can be minimized with artificial tears
Explanation: Tear film abnormalities, such as dry eye syndromes, can negatively impact visual acuity, but their effects can be alleviated through the use of artificial tear preparations.

p.2
Snellen Acuity Notation

What does the number in the denominator of the Snellen notation represent?
A) The distance at which a subject with impaired vision can read
B) The distance at which a subject with unimpaired vision can read
C) The size of the letters on the chart
D) The age of the subject
E) The time taken to read the chart

B) The distance at which a subject with unimpaired vision can read
Explanation: The denominator in the Snellen notation indicates the distance at which a person with unimpaired vision can read the same figure, quantifying visual discrimination of fine detail.

p.5
Testing Conventions and Materials

What should be done with an occluder used for more than one patient?
A) It should be discarded
B) It should be cleaned before reuse
C) It can be reused without cleaning
D) It should be stored in a special case
E) It should be replaced with a new one

B) It should be cleaned before reuse
Explanation: Any occluder that is used for more than one patient must be cleaned before reuse to maintain hygiene and prevent cross-contamination.

p.5
Pinhole Acuity Testing

What does a pinhole acuity test help determine?
A) The patient's color vision
B) The presence of a refractive error
C) The patient's depth perception
D) The patient's peripheral vision
E) The patient's night vision

B) The presence of a refractive error
Explanation: The pinhole acuity test allows clinicians to infer the presence of a refractive error by assessing whether visual acuity improves when viewing through a pinhole occluder.

p.11
Visual Acuity Measurement

What external factors can affect visual acuity measurement results?
A) Only age
B) Only fatigue
C) Patient distraction, fatigue, and age
D) Only psychological factors
E) Only the testing environment

C) Patient distraction, fatigue, and age
Explanation: External variables such as patient distraction, fatigue, and age should be considered when interpreting unexplained poor visual acuity measurement results.

p.9
Testing Procedures for Distance and Near Acuity

If using the Landolt ring chart, you can ask the child to indicate which side of the 'cookie' has a ___ in it.

bite

p.9
Variables in Acuity Measurements

Possible causes of poorer near acuity than distance acuity include ___ and ___ presbyopia.

presbyopia, premature

p.14
Testing Procedures for Distance and Near Acuity

Evaluation of color vision is often performed with a book that displays ___ dot patterns.

multicolored

p.12
Visual Impairment

Moderate low vision is classified as ___ to ___.

20/80, 20/160

p.10
Amblyopia and Visual Impairment

In latent nystagmus, the unoccluded eye develops nystagmus when ___ eye is occluded.

one

p.17
Testing Procedures for Distance and Near Acuity

In the NPC test, the patient is asked to tell you when the image ___ .

doubles

p.14
Testing Procedures for Distance and Near Acuity

Patients with color deficits arrange the chips in the 15-hue test ___ than those with normal color vision.

differently

p.15
Testing Procedures for Distance and Near Acuity

After testing each eye separately, if desired, retest acuity with both eyes ___ and record acuity ___.

simultaneously, OU

p.5
Testing Procedures for Distance and Near Acuity

To avoid memorization, present different charts or optotype ___ whenever possible.

sequences

p.13
Amblyopia and Visual Impairment

The most commonly recognized color vision abnormalities are the X-linked congenital red-green ___ .

deficiencies

p.15
Pinhole Acuity Testing

If visual acuity is worse than 20/20, recheck with a ___.

pinhole

p.5
Pinhole Acuity Testing

A pinhole acuity test can help infer the presence of a ___ error.

refractive

p.14
Special Considerations for Low Vision and Children

When interacting with patients who have low vision, alert them to your ___ beforehand.

movements

p.3
Visual Acuity Measurement

The letters C, D, and O are often confused because their shapes are ___ .

similar

p.14
Special Considerations for Low Vision and Children

Refrain from using the term '___' when counseling patients with severe visual impairment.

blindness

p.14
Special Considerations for Low Vision and Children

Infants and young toddlers respond best to a gentle, ___ approach.

gradual

p.3
Testing Procedures for Distance and Near Acuity

The ___ E and Landolt C tests can be done by matching but involve testing psychophysical components other than vision.

tumbling

p.18
Testing Procedures for Distance and Near Acuity

If light is perceived from straight ahead, move the light sequentially into each of the 4 quadrants of the visual field. Turn the penlight on and off in each field, and ask the patient to identify when the light comes on. If the patient correctly identifies the direction from which the light is coming, record the response as ___ with projection.

LP

p.1
Visual Acuity Measurement

The number in the numerator of the Snellen fraction represents the equivalent of the testing distance from the eye to the ___ being used.

chart

p.11
Testing Procedures for Distance and Near Acuity

Anomalous head position may improve acuity by allowing patients to maintain that head position while measuring ___ visual acuity.

binocular

p.3
Amblyopia and Visual Impairment

The Amblyopia Treatment Study (ATS) visual acuity testing protocol uses isolated HOTV optotypes surrounded by ___.

bars

p.11
Visual Acuity Measurement

The Snellen standard of ___ is considered normal vision.

20/20

p.3
Snellen Acuity Notation

If a patient misses 2 letters on the 20/40 line, the acuity may be expressed as 20/40 ___ 2.

p.11
Visual Acuity Measurement

Profound visual impairment is defined as corrected distance VA less than ___ (including 20/500–20/1000).

20/400

p.18
Testing Procedures for Distance and Near Acuity

If the patient cannot count fingers, move your hand horizontally or vertically before the patient at a distance of approximately 2 feet. Record the distance at which the patient reports seeing your hand move; for example, ___ at 2 ft.

HM

p.1
Snellen Acuity Notation

In Snellen notation, ___/___ is considered normal visual acuity.

20, 20

p.7
Amblyopia and Visual Impairment

In infants, vision should be assessed by testing each eye ___ with the other eye covered.

separately

p.11
Visual Acuity Measurement

Moderate visual impairment is defined as corrected distance VA less than ___ (including 20/70–20/160).

20/60

p.10
Visual Acuity Measurement

What is a crucial factor affecting visual acuity in patients wearing eyeglasses?
A) The color of the frames
B) The cleanliness of the lenses
C) The weight of the glasses
D) The style of the lenses
E) The prescription strength

B) The cleanliness of the lenses
Explanation: Clean lenses are essential for accurate visual acuity measurements; dirty lenses can lead to falsely low acuity readings.

p.15
Testing Conventions and Materials

What should the examiner do if the patient is hesitant during the test?
A) Ignore the hesitation
B) Encourage them to guess
C) Stop the test
D) Change the optotypes
E) Ask them to leave

B) Encourage them to guess
Explanation: If the patient is hesitant, the examiner should reassure them that it is okay to guess, which can help reduce anxiety and facilitate the testing process.

p.15
Pinhole Acuity Testing

What should be done if visual acuity is worse than 20/20?
A) Retest with a different chart
B) Recheck with a pinhole
C) Stop the examination
D) Refer to a specialist
E) Record as is

B) Recheck with a pinhole
Explanation: If visual acuity is worse than 20/20, it is recommended to recheck the acuity using a pinhole to determine if the issue is due to refractive error.

p.8
Testing Conventions and Materials

Which of the following is NOT a method for testing toddlers and preliterate children?
A) Picture chart
B) Lea symbols
C) Landolt C test
D) Snellen chart
E) HOTV chart

D) Snellen chart
Explanation: The Snellen chart is typically used for literate individuals, while toddlers and preliterate children are tested using methods like picture charts and Lea symbols.

p.5
Near Visual Acuity Testing

At what distance is near acuity testing typically performed?
A) 10 inches
B) 16 inches
C) 20 inches
D) 24 inches
E) 30 inches

B) 16 inches
Explanation: Near acuity testing is usually performed at a distance of 16 inches (40 cm), which is considered a standard reading distance for assessing a patient's ability to see clearly.

p.13
Contrast Sensitivity and Other Visual Functions

What does contrast sensitivity measure?
A) Ability to see colors accurately
B) Ability to discern relative darkness and brightness
C) Ability to focus on distant objects
D) Ability to perceive depth and distance
E) Ability to identify moving objects

B) Ability to discern relative darkness and brightness
Explanation: Contrast sensitivity refers to the ability to discern differences in light and dark, as well as details and edges of images, which can be impaired even with good Snellen acuity.

p.9
Variables in Acuity Measurements

What effect does lighting have on acuity measurements?
A) It has no effect
B) It must remain equivalent for tests to be comparable
C) Brighter lighting always improves acuity
D) Dim lighting is preferred
E) Lighting only affects distance acuity

B) It must remain equivalent for tests to be comparable
Explanation: Consistent lighting conditions are crucial for ensuring that acuity tests yield comparable results, as variations can lead to misleading measurements.

p.16
Near Visual Acuity Testing

How should the acuity values be recorded during near visual acuity testing?
A) Only for the left eye
B) Only for the right eye
C) For each eye separately in the patient’s chart
D) As a single value for both eyes
E) In a verbal format

C) For each eye separately in the patient’s chart
Explanation: The acuity value for each eye is recorded separately in the patient’s chart according to the accepted notation method, ensuring accurate documentation of visual acuity.

p.18
Testing Procedures for Distance and Near Acuity

If the patient cannot see the light, dim the room lights and shine the brightest light available toward the patient’s eye again. If the patient cannot see even the brightest light, record the response as ___ (no light perception).

NLP

p.3
Testing Procedures for Distance and Near Acuity

The letters H, O, T, and V were chosen for testing with young children because they are ___ and can be used for matching.

symmetric

p.3
Snellen Acuity Notation

If a patient reads one-half of the letters correctly on the 20/40 line, the vision may be recorded as ___ .

20/40

p.4
Visual Acuity Measurement

What do the abbreviations 'cc' and 'sc' stand for in visual acuity testing?
A) Corrective lenses and special conditions
B) With correction and without correction
C) Central vision and side vision
D) Count fingers and steady fixation
E) Distance and near vision

B) With correction and without correction
Explanation: In visual acuity testing, 'cc' indicates that corrective lenses were worn during the test, while 'sc' indicates that the test was conducted without corrective lenses.

p.8
Testing Conventions and Materials

What is the purpose of using optokinetic nystagmus (OKN) in testing?
A) To measure color vision
B) To assess depth perception
C) To evaluate eye movement and detail discrimination
D) To determine visual acuity
E) To test for peripheral vision

C) To evaluate eye movement and detail discrimination
Explanation: OKN is used to assess the movement of a baby's eyes in response to striped objects, indicating their potential for discriminating detail, which is crucial in early vision assessments.

p.3
Visual Acuity Measurement

What is the easiest letter to recognize in visual acuity tests?
A) O
B) C
C) L
D) D
E) B

C) L
Explanation: The letter L is identified as the easiest to recognize, as it can only be mistaken for a few other letters, primarily the letter I.

p.14
Visual Acuity Measurement

What should be avoided to ensure accurate visual acuity testing?
A) Proper patient positioning
B) Glare on the viewing chart or screen
C) Using appropriate tests for the patient’s abilities
D) Interacting gently with low vision patients
E) Using interesting toys for young children

B) Glare on the viewing chart or screen
Explanation: Avoiding glare on the viewing chart or screen is essential for accurate visual acuity testing, as glare can interfere with the patient's ability to see the chart clearly.

p.13
Contrast Sensitivity and Other Visual Functions

What are the most commonly recognized color vision abnormalities?
A) X-linked congenital red-green deficiencies
B) Blue-yellow deficiencies
C) Achromatopsia
D) Monochromacy
E) All of the above

A) X-linked congenital red-green deficiencies
Explanation: The most commonly recognized color vision abnormalities are the X-linked congenital red-green deficiencies, although other types of color vision anomalies also exist.

p.7
Special Considerations for Low Vision and Children

Newborns should show a consistent ___ response to a bright light.

blink

p.18
Special Considerations for Low Vision and Children

Watch the infant’s eyes for fixation and following movements. Cover 1 eye and repeat the test. Cover the other eye and repeat again. Observe for any difference between the eyes in the quality of ___ and smooth pursuit.

fixation

p.2
Types of Visual Acuity Notations

What does logMAR notation express?
A) The distance of the test
B) The size of the optotypes
C) The logarithm of the minimum angle of resolution
D) The age of the patient
E) The time taken to complete the test

C) The logarithm of the minimum angle of resolution
Explanation: logMAR notation expresses visual acuity as the logarithm of the minimum angle of resolution, providing a standardized way to measure visual acuity.

p.2
Types of Visual Acuity Notations

What is the logMAR value for a visual acuity of 20/20?
A) 0.4
B) 1.0
C) 0.0
D) 0.5
E) 2.0

C) 0.0
Explanation: A visual acuity of 20/20 corresponds to a logMAR value of 0, indicating normal vision.

p.8
Testing Conventions and Materials

What is the purpose of using crowding bars in vision testing?
A) To make the test easier
B) To induce the crowding phenomenon for increased sensitivity in amblyopia testing
C) To distract the patient
D) To measure color discrimination
E) To assess peripheral vision

B) To induce the crowding phenomenon for increased sensitivity in amblyopia testing
Explanation: Crowding bars are used to enhance the sensitivity of tests for amblyopia by inducing the crowding phenomenon, which can affect visual acuity.

p.14
Color Vision Testing

What is the purpose of pseudoisochromatic color plates in color vision evaluation?
A) To measure visual acuity
B) To display multicolored dot patterns for detecting numbers
C) To assess depth perception
D) To evaluate contrast sensitivity
E) To test for glare sensitivity

B) To display multicolored dot patterns for detecting numbers
Explanation: Pseudoisochromatic color plates are used to evaluate color vision by displaying multicolored dot patterns where patients with normal color vision can easily detect specific numbers or figures embedded in the pattern, while those with color vision deficits may not.

p.14
Visual Acuity Measurement

Which of the following is a recommended practice when measuring visual acuity?
A) Use dirty lenses and charts
B) Ignore glare on the viewing chart
C) Ensure all lenses, projectors, and charts are clean
D) Position the patient randomly
E) Use the term 'blindness' when counseling patients

C) Ensure all lenses, projectors, and charts are clean
Explanation: It is crucial to ensure that all lenses, projectors, and charts are clean to avoid variables that could affect visual acuity measurement, ensuring accurate results.

p.12
Visual Acuity Measurement

What is the visual acuity range for normal vision at a normal reading distance?
A) 20/40 to 20/60
B) 20/12 to 20/25
C) 20/200 to 20/400
D) 20/500 to 20/1000
E) 20/80 to 20/160

B) 20/12 to 20/25
Explanation: Normal vision at a normal reading distance is defined as having a visual acuity range of 20/12 to 20/25, indicating that healthy young adults often have better than 20/20 vision.

p.17
Testing Conventions and Materials

During the NPA test, what should the patient report?
A) When they can see the letters clearly
B) When the letters become blurred
C) When they feel discomfort
D) When they can no longer read the chart
E) When they see colors changing

B) When the letters become blurred
Explanation: The patient is asked to state when the letters on the near testing card have become blurred, which indicates the limit of their near point of accommodation.

p.18
Testing Procedures for Distance and Near Acuity

If the light can be seen from straight ahead, colored filters can be placed in front of the light and the patient asked to identify the ___ of the light.

color

p.7
Visual Acuity Measurement

Teller acuity cards are used to estimate acuity in infants and are large photographic plates approximately ___ feet by ___ foot.

3, 1

p.11
Visual Acuity Measurement

The guidelines for issuing noncommercial driving licenses recommend an uninterrupted visual field of ___ horizontal diameter for individuals with 20/40 or better visual acuity.

140°

p.1
Testing Conventions and Materials

What happens to the target size in Snellen testing if the vision is tested at a distance other than 20 feet?
A) It remains the same
B) It must be adjusted to maintain the correct visual angle
C) It is always made smaller
D) It is always made larger
E) It is irrelevant to the test

B) It must be adjusted to maintain the correct visual angle
Explanation: If the vision is tested at a distance other than 20 feet, the target size must be adjusted to ensure that it subtends the correct visual angle of 5 minutes.

p.3
Visual Acuity Measurement

Which letterform is hardest for patients to recognize during visual acuity testing?
A) L
B) C
C) D
D) E
E) O

D) E
Explanation: The letter E is noted as the hardest for patients to recognize and can easily be confused with the number 8, making it a challenging optotype in visual acuity examinations.

p.11
Visual Acuity Measurement

What is the definition of 'visual impairment'?
A) The inability to see at all
B) A subjective judgment by the examiner
C) A condition where visual acuity cannot be improved with optical correction
D) A temporary loss of vision
E) A visual acuity of 20/20

C) A condition where visual acuity cannot be improved with optical correction
Explanation: Visual impairment refers to a situation where visual acuity cannot be achieved with optical correction, distinguishing it from visual disability, which involves subjective judgment.

p.6
Near Visual Acuity Testing

What is the purpose of the near point of accommodation (NPA)?
A) To measure distance vision
B) To determine the nearest point at which the eye can focus clearly
C) To assess color vision
D) To evaluate peripheral vision
E) To measure eye pressure

B) To determine the nearest point at which the eye can focus clearly
Explanation: The NPA is defined as the nearest point at which the eye can focus to form a clear image on the retina, which is crucial for assessing near vision.

p.17
Testing Conventions and Materials

What is the first step in testing for Near Point of Accommodation (NPA)?
A) Ask the patient to close both eyes
B) Place the near testing card at 16 inches from the patient
C) Move the test card away from the patient
D) Use a projected chart for testing
E) Ask the patient to read the smallest line on the chart

B) Place the near testing card at 16 inches from the patient
Explanation: The first step in testing for NPA involves placing the near testing card at a distance of 16 inches (40 cm) from the patient while they wear full distance correction and have one eye occluded.

p.16
Pinhole Acuity Testing

What is the first step in testing pinhole visual acuity?
A) Ask the patient to read the chart
B) Position the patient and occlude the eye not being tested
C) Instruct the patient to hold the test card
D) Record the acuity value
E) Use a multiple pinhole occluder

B) Position the patient and occlude the eye not being tested
Explanation: The first step in testing pinhole visual acuity is to position the patient correctly and occlude the eye that is not being tested, similar to the distance acuity test.

p.16
Pinhole Acuity Testing

How should the patient align the pinhole during the test?
A) By moving the test card
B) By using large body movements
C) By using small hand or eye movements
D) By closing one eye
E) By adjusting the lighting

C) By using small hand or eye movements
Explanation: The patient is instructed to use small hand or eye movements to align the pinhole to resolve the sharpest image on the chart.

p.3
Visual Acuity Measurement

Certain conventional abbreviations such as C, S, M are used for preverbal or ___ children.

nonverbal

p.15
Testing Conventions and Materials

What should be done to the left eye during the visual acuity test?
A) It should be opened
B) It should be occluded
C) It should be examined first
D) It should be treated with drops
E) It should be ignored

B) It should be occluded
Explanation: The left eye should be occluded to ensure that only the right eye is tested, preventing any peeking or interference during the examination.

p.4
Testing Conventions and Materials

What is the purpose of using an occluder during a visual acuity test?
A) To enhance color perception
B) To cover the eye not being tested
C) To measure depth perception
D) To assess peripheral vision
E) To improve contrast sensitivity

B) To cover the eye not being tested
Explanation: An occluder is used to cover the eye that is not being tested, ensuring that the test measures the visual acuity of the eye being assessed without interference.

p.10
Acuity Tests for Special Needs

What technique can be used to assess visual acuity in patients with suspected latent nystagmus?
A) Standard occluder
B) +10.00 to +20.00 diopter lens
C) Bright light exposure
D) Color filters
E) Eye patches

B) +10.00 to +20.00 diopter lens
Explanation: Blurring the fellow eye with a +10.00 to +20.00 diopter lens allows light to enter both eyes, helping to obtain the best possible monocular visual acuity without inducing latent nystagmus.

p.2
Types of Visual Acuity Notations

How is decimal notation related to Snellen notation?
A) It is a different method of measuring distance
B) It converts the Snellen fraction to a decimal
C) It measures color vision
D) It is used for near visual acuity only
E) It is a method for measuring contrast sensitivity

B) It converts the Snellen fraction to a decimal
Explanation: Decimal notation provides a way to express Snellen fractions in decimal form, making it easier to understand visual acuity levels.

p.7
Visual Acuity Examination

What should an examiner do if a patient cannot read the chart even at close distances?
A) Refer them to a specialist
B) Hold up fingers for counting
C) Change the lighting
D) Ask them to guess the letters
E) Use a different chart

B) Hold up fingers for counting
Explanation: If the patient cannot read the standard chart even at close distances, the examiner can hold up fingers and ask the patient to count them, which helps assess their visual function.

p.8
Testing Conventions and Materials

What should be done if a child seems bored with one type of vision test chart?
A) Continue with the same chart
B) Use a different type of chart
C) Stop the testing
D) Increase the difficulty of the test
E) Ask the child to leave

B) Use a different type of chart
Explanation: If a child appears bored or hesitant with one chart, it is advisable to try another type of chart to maintain their engagement and improve testing accuracy.

p.3
Acuity Tests for Special Needs

Which letters are particularly useful for testing visual acuity in young children?
A) A, B, C, D
B) H, O, T, V
C) P, Q, R, S
D) X, Y, Z, W
E) E, F, G, H

B) H, O, T, V
Explanation: The letters H, O, T, and V are symmetric and useful for matching, making them particularly effective for testing visual acuity in young children and nonverbal or illiterate patients.

p.11
Visual Acuity Measurement

What is required for inclusion in the category of 'legal blindness'?
A) Corrected distance VA of 20/40
B) Corrected distance VA of 20/200
C) Severe visual impairment in both eyes
D) Profound visual impairment in one eye
E) Moderate visual impairment in both eyes

C) Severe visual impairment in both eyes
Explanation: Severe visual impairment in both eyes is the criterion typically used for inclusion in the category of 'legal blindness', which affects eligibility for disability benefits.

p.14
Acuity Tests for Special Needs

How should practitioners interact with patients who have severe visual impairment?
A) Grab their hands for guidance
B) Alert them to movements beforehand
C) Use complex language to explain procedures
D) Ignore their visual impairment
E) Stand far away to avoid startling them

B) Alert them to movements beforehand
Explanation: Practitioners should alert patients with severe visual impairment to their movements beforehand to ensure comfort and safety, rather than grabbing their hands or arms, which could be disorienting.

p.13
Acuity Tests for Special Needs

How does age affect the treatment success of amblyopia?
A) Younger patients have less chance of improvement
B) Older patients respond better to treatment
C) Younger patients generally have more successful treatment outcomes
D) Age has no effect on treatment success
E) Treatment is only effective in adults

C) Younger patients generally have more successful treatment outcomes
Explanation: The text indicates that the younger the patient, the more successful the amblyopia treatment tends to be, emphasizing the importance of early intervention.

p.1
Visual Acuity Measurement

What is the smallest angle discernible for normal human vision?
A) 5 minutes of arc
B) 1 minute of arc
C) 10 minutes of arc
D) 15 minutes of arc
E) 30 minutes of arc

B) 1 minute of arc
Explanation: One minute is the smallest angle discernible for normal human vision, which is crucial for understanding visual acuity measurements.

p.8
Testing Conventions and Materials

At what age should horizontal OKN be present in infants?
A) 1 month
B) 3 months
C) 6 months
D) 9 months
E) 12 months

B) 3 months
Explanation: Horizontal OKN should be present by 3 months of age, indicating normal visual development in infants.

p.7
Visual Acuity Examination

What does a Snellen fraction of 5/200 indicate?
A) The patient read the 20/200 line from 5 feet away
B) The patient has perfect vision
C) The patient read the 5/20 line from 200 feet away
D) The patient cannot see at all
E) The patient read the 200/20 line from 5 feet away

A) The patient read the 20/200 line from 5 feet away
Explanation: A Snellen fraction of 5/200 indicates that the patient successfully read the 20/200 line while standing 5 feet in front of the chart, demonstrating their visual acuity level.

p.7
Testing Children and Special Adults

Why is it important to allow toddlers to sit with a familiar caretaker during an examination?
A) To make the examination faster
B) To ensure the child feels comfortable
C) To distract the child
D) To avoid asking questions
E) To limit the number of people in the room

B) To ensure the child feels comfortable
Explanation: Allowing toddlers to sit with a familiar caretaker helps them feel more comfortable and less anxious during the examination, which can lead to more accurate assessments of their visual behavior.

p.3
Visual Acuity Measurement

What notation is used to indicate the number of letters missed during visual acuity testing?
A) Superscript notation
B) Subscript notation
C) Italic notation
D) Bold notation
E) Underline notation

A) Superscript notation
Explanation: The number of letters missed on a line is recorded as a superscript notation added to the acuity measurement, providing additional detail about the patient's performance.

p.17
Testing Conventions and Materials

What is the purpose of testing for Near Point of Convergence (NPC)?
A) To measure distance vision
B) To assess the ability to maintain a single image
C) To evaluate color vision
D) To determine peripheral vision
E) To check for eye strain

B) To assess the ability to maintain a single image
Explanation: The NPC test evaluates the point at which a patient can no longer maintain a single image while converging on a target, which is crucial for assessing binocular vision.

p.17
Acuity Tests for Special Needs

What is the recommended distance for testing acuity in patients with low vision?
A) 5 feet
B) 10 feet
C) 15 feet
D) 20 feet
E) 25 feet

B) 10 feet
Explanation: For patients unable to resolve the largest optotype on the distance acuity chart, they should be positioned 10 feet from the well-illuminated test chart to assess their visual acuity effectively.

p.4
Testing Conventions and Materials

Which of the following is NOT a method of occlusion mentioned for visual acuity testing?
A) Tissue
B) Paddle
C) Eye patch
D) Contact lens
E) Hand

D) Contact lens
Explanation: The methods of occlusion mentioned include a tissue, paddle, eye patch, or hand, but not a contact lens, which is used for correction rather than occlusion.

p.2
Test Targets and Optotypes

What is an optotype in visual acuity testing?
A) A type of eye chart
B) A method of calculating acuity
C) An individual letter, number, or picture on a testing chart
D) A measurement of color vision
E) A type of visual impairment

C) An individual letter, number, or picture on a testing chart
Explanation: An optotype refers to each individual letter, number, or picture used in visual acuity testing, which is crucial for assessing a person's visual ability.

p.11
Visual Acuity Measurement

Which category of visual impairment is defined as corrected distance VA less than 20/60?
A) Severe visual impairment
B) Moderate visual impairment
C) Profound visual impairment
D) Legal blindness
E) Normal vision

B) Moderate visual impairment
Explanation: Moderate visual impairment is defined as corrected distance visual acuity less than 20/60, including ranges from 20/70 to 20/160.

p.5
Near Visual Acuity Testing

What should patients use during near vision testing if they have them?
A) Reading glasses
B) Sunglasses
C) Contact lenses
D) Safety goggles
E) No special equipment is needed

A) Reading glasses
Explanation: If patients use near spectacles, they should wear them during near vision testing to ensure accurate measurement of their visual acuity at reading distances.

p.17
Testing Conventions and Materials

What should be noted during the NPC test?
A) The patient's age
B) The distance at which the image doubles
C) The color of the fixation target
D) The patient's eye color
E) The time taken for the test

B) The distance at which the image doubles
Explanation: During the NPC test, it is important to note the position at which the image doubles or when one eye deviates from the fixation target, as this indicates the limit of convergence.

p.18
Visual Acuity Measurement

What does NLP stand for in visual acuity testing?
A) Normal Light Perception
B) No Light Perception
C) Near Light Perception
D) Non-Perceptive Light
E) Notable Light Perception

B) No Light Perception
Explanation: NLP stands for 'No Light Perception,' indicating that the patient cannot perceive any light, which is a critical finding in visual acuity assessment.

p.18
Visual Acuity Measurement

During the visual field test, what should be recorded if the patient can identify the direction of the light?
A) LP without projection
B) NLP
C) LP with projection
D) CF
E) HM

C) LP with projection
Explanation: If the patient correctly identifies the direction from which the light is coming, it should be recorded as 'LP with projection,' indicating a higher level of visual function.

p.18
Acuity Tests for Special Needs

What type of object should be used to test an infant's visual fixation?
A) A sound-producing object
B) A large, colorful object
C) A small toy that stimulates sight only
D) A bright light
E) A moving object

C) A small toy that stimulates sight only
Explanation: A small toy or attention-attracting object that stimulates sight only should be used to test an infant's visual fixation, as sound-producing objects can distract from the visual assessment.

p.15
Visual Acuity Measurement

What is the ideal testing distance for distance visual acuity examination?
A) 10 feet
B) 15 feet
C) 20 feet
D) 25 feet
E) 30 feet

C) 20 feet
Explanation: The ideal testing distance for distance visual acuity examination is 20 feet from a well-illuminated wall chart, ensuring optimal conditions for accurate measurement.

p.10
Testing Conventions and Materials

What condition might necessitate the use of special spectacle or contact lenses?
A) Myopia
B) Hyperopia
C) Corneal or lenticular astigmatism
D) Presbyopia
E) Color blindness

C) Corneal or lenticular astigmatism
Explanation: Corneal or lenticular astigmatism can require specialized lenses to correct the distortions caused by these conditions, impacting visual acuity.

p.4
Visual Acuity Measurement

What does the abbreviation 'NPA' stand for in visual acuity testing?
A) Near point of accommodation
B) No perception of accommodation
C) Normal point of acuity
D) Near point assessment
E) Non-peripheral acuity

A) Near point of accommodation
Explanation: 'NPA' stands for Near Point of Accommodation, which is a measurement used in visual acuity testing to assess how well the eye can focus on close objects.

p.5
Visual Acuity Examination

Why is it important to determine if a patient is familiar with the optotypes being used?
A) To ensure the test is quick
B) To avoid memorization of the sequence
C) To make the patient comfortable
D) To select the appropriate chart
E) To ensure accurate distance measurements

B) To avoid memorization of the sequence
Explanation: Familiarity with the optotypes can lead to memorization, which may affect the accuracy of the visual acuity test. Presenting different charts or sequences helps mitigate this issue.

p.11
Visual Acuity Measurement

What is the Snellen standard for normal vision?
A) 20/40
B) 20/60
C) 20/20
D) 20/200
E) 20/100

C) 20/20
Explanation: The Snellen standard of 20/20 is considered normal vision, serving as a benchmark for visual acuity measurements.

p.14
Color Vision Testing

What does the 15-hue test (Farnsworth-Munsell D-15 test) involve?
A) Arranging colored chips in a random order
B) Identifying numbers in a dot pattern
C) Arranging 15 pastel-colored chips in a related color sequence
D) Measuring visual acuity with letters
E) Testing for glare sensitivity

C) Arranging 15 pastel-colored chips in a related color sequence
Explanation: The 15-hue test requires patients to arrange pastel-colored chips in a sequence that is obvious to those with normal color vision, while patients with color deficits will arrange them differently, indicating their specific color vision issues.

p.13
Visual Acuity Examination

What is the 'crowding phenomenon' in amblyopia?
A) Difficulty seeing in bright light
B) Easier identification of letters when viewed singly
C) Inability to see colors accurately
D) Increased sensitivity to contrast
E) Difficulty focusing on distant objects

B) Easier identification of letters when viewed singly
Explanation: The crowding phenomenon refers to amblyopic patients being able to identify smaller optotypes more easily when viewed individually rather than in a line with other figures, indicating a specific visual processing challenge.

p.12
Visual Acuity Measurement

What visual acuity range is classified as severe low vision according to US definitions?
A) 20/12 to 20/25
B) 20/200 to 20/400
C) 20/500 to 20/1000
D) 20/80 to 20/160
E) Less than CF 4 ft

B) 20/200 to 20/400
Explanation: Severe low vision is defined as having a visual acuity range of 20/200 to 20/400, which is considered legal blindness in the US.

p.12
Types of Visual Acuity Notations

What is the lay term for amblyopia?
A) Crossed eyes
B) Lazy eye
C) Night blindness
D) Color blindness
E) Tunnel vision

B) Lazy eye
Explanation: Amblyopia is commonly referred to as 'lazy eye,' which describes the condition where one eye has significantly poorer vision than the other due to abnormal visual input during early childhood.

p.9
Variables in Acuity Measurements

Which condition is NOT listed as a possible cause for poorer near acuity compared to distance acuity?
A) Accommodative insufficiency
B) Systemic or topical drugs with an anticholinergic effect
C) High myopia
D) Convergence insufficiency
E) Small, centrally located cataracts

C) High myopia
Explanation: High myopia is not mentioned as a cause for poorer near acuity compared to distance acuity; rather, it is typically associated with distance vision issues.

p.18
Visual Acuity Measurement

If a patient cannot resolve the largest optotypes on the chart, what should you do next?
A) Record the acuity as 20/20
B) Ask the patient to count the number of fingers displayed
C) Move the chart closer to the patient
D) Shine a light in the patient's eye
E) Ask the patient to read the chart again

B) Ask the patient to count the number of fingers displayed
Explanation: If the patient cannot resolve the largest optotypes, the next step is to display 2 or more fingers and ask the patient to count them, which helps assess their visual acuity further.

p.18
Visual Acuity Measurement

What should be done if the patient cannot count fingers during the visual acuity test?
A) Record the acuity as 20/200
B) Shine a penlight in their eye
C) Move your hand horizontally or vertically
D) Ask the patient to read the chart again
E) Use colored filters

C) Move your hand horizontally or vertically
Explanation: If the patient cannot count fingers, the next step is to move your hand horizontally or vertically at a distance of approximately 2 feet to assess their ability to detect motion.

p.10
Acuity Tests for Special Needs

What is a potential effect of nystagmus on visual acuity measurements?
A) It has no effect
B) It can improve acuity
C) It can lower acuity measurements
D) It only affects peripheral vision
E) It only affects children

C) It can lower acuity measurements
Explanation: Nystagmus, characterized by spontaneous oscillatory movements of the eyes, can interfere with the ability to align the fovea on the object of regard, resulting in lower acuity measurements.

p.1
Visual Acuity Measurement

What is visual acuity primarily a measure of?
A) Color perception
B) Depth perception
C) Angular measurement relating testing distance to object size
D) Peripheral vision
E) Eye movement coordination

C) Angular measurement relating testing distance to object size
Explanation: Visual acuity is defined as an angular measurement that relates the testing distance to the minimal object size resolvable at that distance, making it a key component of vision assessment.

p.1
Snellen Acuity Notation

What is the purpose of the denominator in Snellen notation?
A) To indicate the size of the optotype
B) To represent the distance at which the target subtends a visual angle of 5 minutes
C) To show the testing distance in meters
D) To express the level of contrast sensitivity
E) To denote the type of visual function being tested

B) To represent the distance at which the target subtends a visual angle of 5 minutes
Explanation: The denominator in Snellen notation indicates the distance at which the target subtends a visual angle of 5 minutes, providing context for the visual acuity measurement.

p.5
Pinhole Acuity Testing

What is the recommended diameter for a pinhole used in acuity testing?
A) 1.0 mm
B) 2.4 mm
C) 3.5 mm
D) 5.0 mm
E) 10.0 mm

B) 2.4 mm
Explanation: A pinhole no more than 2.4 mm in diameter is recommended for acuity testing to ensure that only central rays of light are admitted, which helps in assessing refractive errors.

p.7
Testing Children and Special Adults

What does fixation preference testing help detect in preverbal children?
A) Color blindness
B) Amblyopia
C) Nearsightedness
D) Farsightedness
E) Strabismus

B) Amblyopia
Explanation: Fixation preference testing, such as the induced tropia test, is useful for detecting amblyopia in preverbal children by assessing their visual preference between the two eyes.

p.6
Near Visual Acuity Testing

What is the normal range for the near point of convergence (NPC)?
A) 1 cm to 3 cm
B) 4 cm to 6 cm
C) 6 cm to 10 cm
D) 10 cm to 15 cm
E) 15 cm to 20 cm

C) 6 cm to 10 cm
Explanation: The normal NPC is stated to be between 6 cm and 10 cm, regardless of a person’s age, indicating the distance at which both eyes can converge while maintaining a single image.

p.9
Variables in Acuity Measurements

Which of the following can cause falsely high or low acuity measurements?
A) Proper lighting conditions
B) Patient's age
C) Presbyopia or premature presbyopia
D) Use of colored charts
E) The presence of a parent

C) Presbyopia or premature presbyopia
Explanation: Conditions like presbyopia can lead to inaccurate acuity measurements, highlighting the importance of considering various factors that may affect visual acuity.

p.18
Visual Acuity Measurement

What does 'CF at 2 ft' indicate in visual acuity testing?
A) The patient can see colors at 2 feet
B) The patient can count fingers at 2 feet
C) The patient has normal vision at 2 feet
D) The patient can read the chart at 2 feet
E) The patient has no light perception

B) The patient can count fingers at 2 feet
Explanation: 'CF at 2 ft' indicates that the patient is able to count fingers at a distance of 2 feet, which is a measure of their visual acuity when they cannot read the chart.

p.1
Snellen Acuity Notation

What does the Snellen notation of 20/20 indicate?
A) Poor visual acuity
B) Normal visual acuity
C) Exceptional visual acuity
D) Near visual acuity
E) Visual acuity at 60 feet

B) Normal visual acuity
Explanation: In Snellen notation, 20/20 is considered normal visual acuity, indicating that a person can see at 20 feet what should normally be seen at that distance.

p.7
Visual Acuity Examination

What should an examiner do if a patient cannot read the largest line of the visual acuity chart?
A) Stop the examination
B) Repeat the test at shorter distances
C) Change the chart
D) Use a different testing method
E) Ask the patient to guess the letters

B) Repeat the test at shorter distances
Explanation: If a patient is unable to read the largest line, the examiner should repeat the test at successively shorter distances, noting the distance at which the acuity measurement is successfully taken, which is then used as the numerator of the Snellen fraction.

p.7
Testing Children and Special Adults

What is a sign of normal visual function in infants by the age of 3 months?
A) Ability to crawl
B) Ability to maintain steady fixation and follow an object
C) Ability to recognize faces
D) Ability to speak
E) Ability to reach for objects

B) Ability to maintain steady fixation and follow an object
Explanation: Infants with normal visual function are expected to maintain steady fixation and follow an object by the age of 3 months, indicating healthy visual development.

p.6
Near Visual Acuity Testing

Which tool is recommended for testing near visual acuity in adults?
A) Snellen chart
B) A Rosenbaum pocket vision screener
C) A Lebensohn chart
D) Both B and C
E) A standard ruler

D) Both B and C
Explanation: The text specifies that a Rosenbaum pocket vision screener or a Lebensohn chart should be used to test near visual acuity in adults, making both options correct.

p.6
Near Visual Acuity Testing

What condition is referred to when the near point of accommodation (NPA) recedes with age?
A) Myopia
B) Hyperopia
C) Presbyopia
D) Astigmatism
E) Strabismus

C) Presbyopia
Explanation: The text mentions that as people age, their NPA recedes, which is a condition known as presbyopia, affecting their ability to focus on near objects.

p.6
Acuity Tests for Special Needs

Which testing method is suitable for infants and toddlers with low vision?
A) Standard Snellen chart
B) Allen reduced picture cards
C) Jaeger notation
D) Pinhole acuity testing
E) Contrast sensitivity testing

B) Allen reduced picture cards
Explanation: The text specifies that for children, near visual acuity can be tested with Allen reduced picture cards, making it an appropriate method for infants and toddlers.

p.13
Contrast Sensitivity and Other Visual Functions

What can glare testing suggest?
A) Presence of color blindness
B) Presence of cataract or other opacity
C) Presence of retinal detachment
D) Presence of high blood pressure
E) Presence of macular degeneration

B) Presence of cataract or other opacity
Explanation: Glare testing can indicate the presence of cataracts or other opacities, as it assesses how light scattering affects visual quality.

p.12
Visual Acuity Measurement

What is a common characteristic of profound visual impairment (20/500 to 20/1000)?
A) Normal reading ability
B) Limited spot reading with visual aids
C) Adequate mobility without aids
D) Ability to drive
E) Clear vision under all circumstances

B) Limited spot reading with visual aids
Explanation: Individuals with profound visual impairment (20/500 to 20/1000) typically have limited spot reading capabilities even with visual aids, indicating significant challenges in visual tasks.

p.18
Visual Acuity Measurement

What is the first step in standard distance acuity testing?
A) Record the patient's age
B) Note the corresponding acuity measurement on the chart
C) Ask the patient to count fingers
D) Shine a penlight in the patient's eye
E) Move the patient's hand horizontally

B) Note the corresponding acuity measurement on the chart
Explanation: The first step in standard distance acuity testing is to note the acuity measurement shown at the line of the chart, which is essential for recording the patient's visual acuity accurately.

p.3
Testing Conventions and Materials

What is a potential issue with using picture charts for visual acuity testing in children?
A) They are too complex
B) They can lead to over-estimation of visual acuity
C) They require advanced literacy skills
D) They are not engaging for children
E) They are difficult to interpret

B) They can lead to over-estimation of visual acuity
Explanation: Picture charts can result in over-estimation of visual acuity because the optotypes are not equally recognizable, leading to inaccuracies due to educated guessing by children.

p.3
Snellen Acuity Notation

What does the Snellen acuity expression represent?
A) The distance from which the patient can read the chart
B) The number of letters missed on the chart
C) The size of the optotype compared to the standard line
D) The patient's age
E) The type of chart used

C) The size of the optotype compared to the standard line
Explanation: The Snellen acuity expression is determined by the size of the optotype that the patient can read correctly, with the distance from the chart being the numerator and the size of the optotype being the denominator.

p.13
Acuity Tests for Special Needs

What are common causes of unilateral amblyopia?
A) Anisometropia, strabismus, and unilateral media opacities
B) High blood pressure and diabetes
C) Age-related macular degeneration
D) Retinal detachment and glaucoma
E) Cataracts and dry eye syndrome

A) Anisometropia, strabismus, and unilateral media opacities
Explanation: Unilateral amblyopia can be caused by conditions such as anisometropia, strabismus, and unilateral media opacities like monocular congenital cataracts, which affect visual development.

p.12
Acuity Tests for Special Needs

What type of reading aids are recommended for someone with moderate low vision (20/80 to 20/160)?
A) Regular bifocals
B) Strong reading glasses or vision magnifiers
C) High-power reading lenses
D) Video magnifier
E) Talking devices

B) Strong reading glasses or vision magnifiers
Explanation: For individuals with moderate low vision, strong reading glasses or vision magnifiers are usually adequate for reading, although this level of vision is typically insufficient for obtaining a driving license.

p.9
Variables in Acuity Measurements

What external variable can affect the comparability of acuity tests?
A) The patient's mood
B) The cleanliness of the chart
C) The time of day
D) The age of the patient
E) The type of glasses worn

B) The cleanliness of the chart
Explanation: A dirty chart can make smaller letters more difficult to identify, thus affecting the accuracy of the acuity test results.

p.16
Pinhole Acuity Testing

What should the patient do while using the pinhole occluder?
A) Close both eyes
B) Look at the distance chart through the pinhole
C) Move the test card closer
D) Read the chart without the pinhole
E) Adjust the lighting in the room

B) Look at the distance chart through the pinhole
Explanation: The patient is instructed to look at the distance chart through the single pinhole or any of the multiple pinholes to assess visual acuity.

p.16
Pinhole Acuity Testing

What is the purpose of recording the Snellen acuity obtained?
A) To determine the patient's age
B) To assess the effectiveness of corrective lenses
C) To document the visual acuity achieved with the pinhole
D) To compare with previous tests
E) To evaluate the patient's overall health

C) To document the visual acuity achieved with the pinhole
Explanation: The Snellen acuity obtained during the pinhole test is recorded to document the visual acuity achieved, often preceded or followed by the abbreviation PH.

p.9
Visual Acuity Measurement

What is a method to engage a child during a visual acuity test using the tumbling E chart?
A) Ask the child to read letters aloud
B) Ask the child to point in the direction the legs are pointing
C) Ask the child to close their eyes
D) Ask the child to draw the letters
E) Ask the child to sing a song

B) Ask the child to point in the direction the legs are pointing
Explanation: Engaging the child by asking them to indicate the direction the legs of the letter point helps in assessing their visual acuity in a fun and interactive manner.

p.16
Near Visual Acuity Testing

What is the first step in testing near visual acuity?
A) Ask the patient to occlude one eye
B) Instruct the patient to hold the test card at the specified distance
C) Record the acuity value
D) Use a pinhole occluder
E) Adjust the lighting

B) Instruct the patient to hold the test card at the specified distance
Explanation: The first step in testing near visual acuity is to instruct the patient to hold the test card at the distance specified on the card while wearing their habitual corrective lens.

p.18
Acuity Tests for Special Needs

What is the first step in testing an infant's fixing and following behavior?
A) Use a sound-producing object
B) Seat the infant on a familiar adult's lap
C) Move the object quickly
D) Cover one eye
E) Use a bright light

B) Seat the infant on a familiar adult's lap
Explanation: The first step in testing an infant's fixing and following behavior is to seat the infant on a familiar adult's lap to ensure the infant is comfortable during the test.

p.17
Acuity Tests for Special Needs

What should be done if a low vision patient cannot identify the largest optotype?
A) Stop the test
B) Use a projected chart
C) Halve the testing distance
D) Change the lighting
E) Ask the patient to guess

C) Halve the testing distance
Explanation: If the patient cannot identify the largest optotype, the protocol is to repeatedly halve the testing distance (up to 2.5 feet) and retest until the patient can successfully identify half the optotypes on a line.

p.18
Visual Acuity Measurement

What is the purpose of using colored filters during visual acuity testing?
A) To assess distance vision
B) To determine color perception
C) To measure light sensitivity
D) To check for eye movement
E) To evaluate hand motion detection

B) To determine color perception
Explanation: Colored filters are used to assess whether the patient can identify the color of the light, which helps evaluate their color perception capabilities.

Study Smarter, Not Harder
Study Smarter, Not Harder