chapter 16 supplemental skills Flashcards
You are inputting data for IOL calculations and notice that the K readings are 44.5/42.75. This type of reading:
a) should prompt you to repeat the measurement
b) alerts you that lenticular astigmatism may exist
c) alerts you that axillary astigmatism may exist
d) is acceptable
d- is acceptable
The manufacturer of a given IOL often supplies a specific number that must be entered into the IOL calculations when the lens is to be used. This number is referred to as a(n):
a) A-constant
b) fudge factor
c) personal identification number
d) optical constant
a- A-constant
Which of the following poses problems in obtaining accurate measurements for IOL calculations?
a) patients with aphakia
b) patients who have had corneal refractive surgery
c) patients with posterior subcapsular cataracts
d) patients with dense brown cataracts
b- patients who have had corneal refractive surgery
When calculating IOL power, each of the following are necessary except:
a) white-to-white corneal diameter
b) axial length
c) a calculation formula
d) K readings
a- white-to-white corneal diameter
It is important to estimate the anterior chamber depth prior to dilation because:
a) open angles may precipitate an angle-closure glaucoma attack
b) narrow angles may precipitate an angle-closure glaucoma attack
c) narrow angles do not dilate as well and therefore require stronger dilating drugs
d) open angles dilate quickly and therefore require weaker dilating drugs
d- open angles dilate quickly and therefore require weaker dilating drugs
In slit-lamp assessment of the corneal periphery, the dark interval should be a minimum of approximately how much of the total corneal width for the angle to be considered open and safe for dilation?
a) one-half
b) three-fourths
c) one-fourth
d) one-third
c - one-fourth
When evaluating anterior chamber depth with the slit lamp, the illumination technique used is:
a) cobalt blue filter
b) narrow beam
c) wide beam
d) pinpoint beam
b- narrow beam
Measuring corneal thickness via nonoptical pachymetry involves the use of:
a) specular microscopy
b) ultrasound
c) the slit-lamp microscope
d) a contact mirrored lens
b- ultrasound
The type of pachymetry used to evaluate a glaucoma suspect is:
a) optical coherence tomography
b) central corneal curvature
c) peripheral corneal thickness
d) central corneal thickness
d- central corneal thickness
The IOLMaster must be calibrated daily using a:
a) calibration weight
b) set of metal spheres of known curvature
c) “test eye”
d) calibration bar
c - “test eye”
The Schirmer’s test might be indicated in all of the following except:
a) dry eye
b) contact lens pre-evaluation
c) epiphora
d) dacryocystitis
d- dacrocystitis
The difference between Schirmer’s test I and II is:
a) the length of the test
b) the type of strips used
c) the use of an anesthetic
d) there is no difference
c- the use of an anesthetic
Schirmer’s test II is used to measure:
a) reflux tears
b) reflex tears
c) normal tearing
d) drainage rate
c- normal tearing
Measuring time for the Schirmer’s test is:
a) 1 minute
b) 2 minutes
c) 5 minutes
d) 10 minutes
c- five minutes
A normally functioning lacrimal gland will produce how much wetting on a Schirmer’s test strip after 5 minutes?
a) 1 mm
b) 2.5 mm
c) 6 mm
d) 10 mm
d- 10 mm
All of the following are used in evaluating tear break-up time (TBUT) except:
a) slit-lamp microscope
b) tear filter papers
c) fluorescein dye
d) cobalt blue light
b- tear filter papers
When performing the TBUT test, the observer is looking for:
a) the appearance of dry spots
b) pooling of the fluorescein dye
c) reflex tearing
d) drainage of tears off the eye
a- the appearance of dry spots
A TBUT of which of the following would indicate tear film dysfunction?
a) 10 seconds
b) 20 seconds
c) 30 seconds
d) 40 seconds
a- 10 seconds
A patient with which of the following potential diagnoses would be tested with rose bengal?
a) glaucoma
b) corneal foreign body
c) severe dry eye
d) contact lens fitting
c- severe dry eye
Each of the following might be evaluated using rose bengal except:
a) corneal endothelial drop-out
b) corneal abrasion
c) corneal herpes simplex
d) keratitis
a- corneal endothelial drop-out
Each of the following is true regarding rose bengal except:
a) stinging may be severe
b) it requires the use of the cobalt blue filter
c) it stains tissue a reddish-pink color
d) it is available in drop and strip form
b- it required the use of the cobalt blue filter
When performing a brightness acuity glare test, it is best to do which of the following?
a) Allow the patient to adjust to the light level before reading the letters.
b) Do glare testing through the phoroptor.
c) Time how long it takes for the patient to read the letters.
d) Calibrate the instrument.
a- allow the patient to adjust to the light level before reading the letters
The photosensitive pigments of the eye are sensitive to:
a) red, green, and blue
b) red, blue, and yellow
c) red, green, and yellow
d) green, blue, and yellow
a- red, green and blue
Color vision testing is used to detect all of the following except:
a) presence of normal color vision
b) type and severity of color defect
c) those who may not qualify for certain jobs
d) differentiate between congenital or acquired color blindness
D- differentiate between congenital or acquired color blindness
The Ishihara color plates are useful:
a) for screening purposes, such as job applications
b) for detailed information on a patient’s color defect c) as a basis for referral to a neuro-ophthalmologist
d) only for those who already know they have a defect
A- for screening purposes, such as job applications
Illumination for the color plates test:
a) varies according to the type of test administered
b) should come from an easel lamp in a dark room
c) should be natural daylight
d) should be one-fifth of the room light
A- varies according to the type of test administered
Before proceeding with the actual color plate test:
a) the patient is shown a sample that is discernable to normal and abnormal alike
b) the patient is shown a sample that is discernable only to those with a color deficit
c) the lights should be dimmed
d) the patient should be dilated
A- the patient is shown a sample that is discernible to normal and abnormal alike
How long should the patient be given to recognize the figure in a color plate?
a) 2 to 3 seconds
b) 10 to 15 seconds
c) 30 to 40 seconds
d) as long as he or she needs
A- 2 to 3 seconds
When using color plates, a score indicates abnormal color vision:
a) when the patient misses 5% of the plates
b) when the patient misses 10% of the plates
c) when the patient misses 20% of the plates
d) varies according to the type of test
D- varies according to the type of test
Hereditary color vision defects usually affect:
a) both eyes equally
b) one eye more than the other
c) one eye only
d) the dominant eye
A- both eyes equally
Which of the following should be color-vision tested one eye at a time?
a) suspected blue-yellow defect
b) suspected red-green defect
c) suspected congenital color defect
d) suspected acquired color defect
D- suspected acquired color defect
Acquired color vision defects:
a) can often be cured by wearing a green contact lens on one eye
b) can often be cured if the causative factor is eliminated
c) can often be cured by retinal surgery
d) can often be cured by injections of photosensitive pigment
B- can often be cured if the causative factor is eliminated
If the patient is suspected of having an acquired color vision defect, all of the following apply except:
a) each eye can have a different degree of deficit
b) the defect tends to remain stable over time
c) he or she will tend to make color errors scattered all across the color wheel
d) they can resolve
B- the defect tends to remain stable over time
When should a child have his or her color vision checked?
a) Only if there is a family history of color blindness. b) Prior to age 4.
c) Before starting school.
d) By age 10.
C- before starting school
Color vision defects in children are frequently detected among those with:
a) reading disabilities
b) retinoblastoma
c) sickle cell disease
d) attention deficit disorder
A - reading disabilities
In evaluating an axial length scan, the retinal echo must be:
a) to the right of the scleral and orbital echoes
b) the shortest of the scan
c) in the center of the scan
d) to the left of the scleral and orbital echoes
D- to the left of the scleral and orbital echoes
In an axial length A-scan, if there is only one tall echo from the back of the eye with no other echoes behind it, this indicates:
a) the presence of a tumor and that an x-ray should be done
b) that the sound beam is directed to the macula and the measurement is correct
c) that the sound beam is directed to the optic disc and the measurement is incorrect
d) that the sound beam is directed at the macula and the measurement is incorrect
C- that the sound beam is directed to the macula and the measurement is correct
A measurement error of 1 mm in an axial eye length could result in an unwanted postoperative refractive error of as much as:
a) 0.1 D
b) 1.0 D
c) 0.3 D
d) 3.0 D
D- 3.0 D
When comparing the axial lengths of a patient’s left and right eye, how much of a difference between the eyes should signal you to repeat the measurement of both eyes?
a) 1.0 mm
b) 0.5 mm
c) 0.3 mm
d) 0.1 mm
C- 0.3 mm
Laser interferometry uses which type of laser light?
a) microwave
b) ultrasonic
c) infrared
d) polarized
C- infrared
The IOLMaster eliminates which of the following sources of error?
a) shortened axial length due to compression
b) distorted corneal curvature due to improper alignment
c) inaccurate corneal diameter measurements due to parallax error
d) mathematical formula selection errors
A- shortened axial length due to compression
The IOLMaster evaluates each of the following except: a) horizontal corneal diameter
b) corneal curvature
c) refractive error
d) anterior chamber depth
C- refractive error
For safety reasons, the limit for the number of readings that may be taken per eye per day with the IOLMaster is:
a) 5
b) 10
c) 15
d) 20
D- 20
The ideal IOLMaster axial length graph is:
a) a tall, central spike with only one peak and smaller spikes on either side
b) a tall, central spike with two peaks and smaller spikes on the left
c) a tall spike with only one peak and smaller spikes to the left
d) a small, central spike and taller spikes on either side
A- a tall, central spike with only one peak and smaller spikes on either side
With the IOLMaster, the ideal signal-to-noise ratio is: a) 0 or less
b) 0.5
c) 1.5
d) 2.0 or more
D- 2.0 or more
