Equipment Maintenance and Repair CH4

Question 1

Acuity projector slides can be cleaned by:
a) washing with soap and water
b) spraying with commercial cleaner
c) wiping with a dry lens wipe
d) wiping with a wet lens wipe

Answer 1

c) Use a dry lens wipe to clean acuity projector slides. Liquids can dissolve the paint and
ruin the slides.

Question 2

Which of the following will help prevent dust build-up on the lenses of a direct ophthalmoscope?

a) the direct ophthalmoscope has no built-in lenses
b) cleaning daily with cleanser
c) removing the instrument facing for direct access to the lenses
d) storing the instrument with the lens setting on zero

Answer 2

d) With the setting on zero, there are no exposed lenses in the instrument’s aperture.

Question 3

Which of the following is not appropriate when cleaning an indirect ophthalmoscope?

a) cleaning the front surface mirror with a brush
b) rubbing debris off the bulb with the finger
c) cleaning the bulb contacts by scraping with a file
d) wiping the headband with an alcohol wipe

Answer 3

b) Oil from the fingers is transferred to the bulb if you touch it. (The front surface mirror
may also be cleaned with a lens wipe moistened with ether and alcohol in a ratio of 1:4.)

Question 4

Unless the manufacturer’s instructions indicate otherwise, the perimeter bowl surface
may be cleaned with:
a) mild detergent and water
b) lighter fluid
c) contact lens solution
d) lens cleaner

Answer 4

a) A mild detergent and water are appropriate for cleaning the perimeter bowl surface.

Question 5

When brushing or wiping the perimeter bowl surface, it is important to avoid:
a) any moisture at all
b) excessive pressure/friction
c) fibrous cotton balls
d) using a soft brush or cloth

Answer 5

b) Putting too much pressure on an area inside the bowl might change the reflective properties of the bowl in that area or scratch the finish.

Question 6

Dirty tangent screen test objects should be cleaned with:
a) cleanser
b) an alcohol wipe
c) soap and water
d) acetone

Answer 6

c) Mild soap and water are the choice for cleaning dirty test objects.

Question 7

Discolored tangent screen white test objects should be:
a) replaced
b) painted with correction liquid
c) used as is
d) wiped with an alcohol wipe

Answer 7

a) If the test objects are discolored, they should be replaced, not “repaired.” If they are too dingy, they can affect the accuracy of the test.

Question 8

The tangent screen itself can be cleaned:
a) by gentle whisking with a very soft brush
b) by brushing with a wire brush
c) with a commercial dry-cleaning product
d) with soap and water

Answer 8

a) Answers b through d are too aggressive. A gentle whisking is appropriate.

Question 9

To prevent dirt from collecting on the back surface of the refractor/phoroptor lenses:

a) use the widest pupillary distance possible
b) adjust the forehead rest to avoid lash/lens contact
c) make sure the refractor is level
d) request that patients remove mascara before refractometry

Answer 9

b) Oil and makeup can accumulate on the lenses when there is contact between the lids and lenses. Adjust the forehead rest to push the patient back a little. (But keep in mind that this
also increases the vertex distance.)

Question 10

If the internal lenses of the refractor are dirty:

a) spray them through the aperture with lens cleaner
b) open the refractor and clean the lenses one at a time
c) add one line of acuity to everyone’s measurement
d) have the instrument professionally cleaned

Answer 10

d) The refractor (phoroptor) is a complicated instrument and should be cleaned only by a
trained professional. Never spray anything into the instrument.

Question 11

To clean the friction plate under the joystick:

a) wipe with an alcohol wipe
b) remove the plate, and put it in the autoclave
c) rub with bathroom cleanser
d) spray with lens cleaner

Answer 11

a) The slit lamp will not move smoothly if the friction plate is dirty. Clean it with an alco-
hol wipe.

Question 12

To lubricate the friction plate under the joystick:
a) lightly coat with cooking oil and wipe it almost dry
b) lightly coat with automotive oil and wipe it almost dry
c) lightly coat with silicone oil and wipe it almost dry
d) lightly sprinkle with graphite

Answer 12

c) Alcohol will dissolve oil and grease, so lubricate the clean friction plate with silicone oil or WD-40 (The WD-40 Company, San Diego, CA).

Question 13

Solid ultrasound probes should be cleaned:

a) only if an infectious disease is suspected
b) once each week
c) once each day
d) between each patient exam

Answer 13

d) Because the probe makes direct contact with the eye tissues, it should be cleaned
between patients.

Question 14

All of the following tend to loosen the glue of a mounted lens except:
a) drying out over time
b) heat
c) cool water
d) alcohol or acetone

Answer 14

c) Cool water does not affect the glue of a mounted lens. The other items listed can cause the glue to loosen.

Question 15

Unless the manufacturer’s instructions state otherwise, a glass lens (nonbloomed) may
be cleaned by any of the following except:

a) 4:1 ratio of ether and alcohol
b) commercial chrome cleaner
c) 1:1 ratio of ammonia and isopropyl alcohol
d) commercial glass or lens cleaner

Answer 15

b) Chrome cleaner is not appropriate for use on glass lenses. “Blooming” refers to a special
coating on the lens.

Question 16

Do not use commercial glass cleaner on plastic lenses because:
a) this can scratch the surface
b) this can remove lens coatings
c) this can cloud the lens
d) this can cause crazing

Answer 16

c) A plastic lens may cloud if cleaned with commercial glass cleaner.

Question 17

Besides soap and cool water, which of the following can be used to clean plastic lenses?

a) contact lens solution
b) lighter fluid
c) bathroom cleanser
d) baking soda

Answer 17

a) Because contact lenses are plastic, it makes sense that you can use contact lens solution
to clean plastic lenses. The other items are too abrasive or caustic.

Question 18

Which of the following will remove the coating on a bloomed lens (such as the indirect
ophthalmoscope lens)?

a) gently wiping the dry lens with a tissue
b) wiping the lens with ethyl or methyl alcohol
c) blowing the lens with compressed air
d) heavily rubbing the lens to remove fingerprints

Answer 18

d) Friction can remove the coating on a bloomed lens. Be gentle!

Question 19

When cleaning a lens that is fixed into an instrument:
a) spray lens cleaner on the lens in the instrument
b) use a stream bottle to irrigate the lens in the instrument
c) spray lens cleaner on a wipe, and clean the lens with the wipe
d) fixed lenses cannot be cleaned

Answer 19

c) Never spray cleaner into an instrument. If you want to use cleaner, spray it on a wipe
first. Then, use the wipe on the instrument

Question 20

The best way to remove dust from a fundus camera lens is to first:
a) dust it with a camel’s hair brush
b) blow off dust with air
c) wipe dust off with a dry cloth
d) clean dust off with isopropyl alcohol

Answer 20

b) The order of cleaning for a camera lens is blow using a bulb syringe (not your breath!),
brush, and wipe

Question 21

Which surface of an exophthalmometer might require disinfection?
a) the mirrors
b) the gauges
c) the prisms
d) the points of patient contact

Answer 21

d) Any part of the exophthalmometer (or any instrument) that touches the patient should be
cleaned between patients.

Question 22

Which surface of an ophthalmodynamometer might require disinfection?
a) the tip
b) the gauge
c) the lens
d) the watch glass

Answer 22

a) See answer 21. The tip of the instrument touches the eye and therefore must be disinfected after every use

Question 23

Which of the following is untrue regarding front surface mirrors?

a) The silver coating can be rubbed off over time.
b) The coating can be scratched by mishandling.
c) They produce a faint double image of the reflection.
d) They reflect 100% light transmission

Answer 23

c) Front surface mirrors do not produce a double image. That is why they are used in optical situations.

Question 24

Prior to cleaning a front surface mirror, one should:
a) rub with a cotton ball to remove loose dust
b) use canned air to remove loose dust
c) blow on it to remove loose dust
d) spray it with water

Answer 24

b) Prior to cleaning the mirror, use canned air or an air bulb to remove loose debris, which
could scratch the mirror when it is being wiped. If you use canned air, be sure it is approved for use on mirrors and lenses; the type usually used for general office use sometimes has a liquid additive that can coat the surface

Question 25

Which of the following can be used to clean a front surface mirror?
a) a paper towel and commercial glass cleaner
b) a cotton-tipped applicator and dry baking soda
c) a fingertip to rub off smudges
d) a lens wipe with a 4:1 ratio of ether and alcohol

Answer 25

d) A front surface mirror can be scratched easily, and a little bit of the silver is rubbed off
every time it is cleaned. Clean it with a lens wipe moistened with ether and alcohol, gently
moving the wipe in down-strokes. Do not rub the mirror. (Alternately, in Stein, Stein, and
Freeman’s The Ophthalmic Assistant, 8th Edition, the authors suggest using small spritzes of commercial glass cleaner and cotton balls.)

Question 26

A mirror surface should be dried by:

a) patting with a lint-free lens wipe
b) wiping with a lint-free lens wipe
c) rubbing with a tissue or cotton ball
d) patting with a paper towel

Answer 26

a) To avoid scratching, do not rub the mirror, and do not use an abrasive wipe. If necessary,
pat dry with a lint-free lens wipe or cotton ball

Question 27

Which surface is not affected by friction during cleaning?
a) front surface mirrors
b) bloomed lenses
c) projector screens
d) glass trial lenses

Answer 27

d) The items in answers a through c can all be ruined by hard rubbing

Question 28

A projector screen is cleaned by:
a) wiping with an alcohol wipe
b) scrubbing with cleanser
c) a solution of mild detergent
d) commercial glass cleaner

Answer 28

c) The projector screen is designed to be highly reflective. Clean it gently with mild detergent.

Question 29

One of the easiest and least expensive ways to prolong the life of ophthalmic/optometric equipment is to:
a) wipe it daily with an alcohol wipe
b) have it serviced every 6 months
c) change bulbs and batteries every 6 months
d) cover or store it when not in use

Answer 29

d) Covering or storing equipment prevents dust build-up and reduces breakage.

Question 30

Turning a screw counterclockwise (to the left) will cause it to:
a) tighten
b) loosen
c) strip out
d) fall out

Answer 30

b) Remember the little ditty, “Righty tighty, lefty loosey.” Turning a screw to the left, or
counterclockwise, will loosen it

Question 31

The first several turns of inserting a screw are difficult. You should:
a) force it
b) use a hammer
c) stop and try resetting the screw
d) spray lubricant on the instrument

Answer 31

c) Forcing a screw may strip it, making it nearly impossible to remove later. It could also
cause the instrument housing to crack at that point.

Question 32

To extend the life of a slit-lamp bulb:

a) use the lowest voltage setting as much as possible
b) scrape the contact points weekly
c) turn it 180 degrees weekly
d) use the lowest illumination as much as possible

Answer 32

a) Use the lowest voltage setting of the slit lamp or any other instrument to prolong the bulb life.

Question 33

f the filament of a bulb is aligned incorrectly in the housing:

a) the bulb will blow out
b) chromatic aberration will occur in the light field
c) the light will be deviated from prismatic power
d) the projected light will not illuminate the entire field

Answer 33

d) If the bulb filament is not lined up, then the field will not be entirely lit

Question 34

f the light in a piece of electrical equipment begins to flicker or does not come on, the
first and easiest thing to check is:
a) the filament
b) the bulb’s seating
c) the instrument’s plug
d) the instrument’s fuse

Answer 34

c) The golden rule in troubleshooting electrical equipment is always check the plug first!

Question 35

When changing light bulbs in a piece of equipment, all of the following are important
except:
a) turn off and unplug the instrument
b) allow the old bulb to cool, if it is hot
c) remove the old bulb with pliers
d) do not touch the glass of the new bulb

Answer 35

c) If you try to remove the bulb with pliers, the bulb may break. Then, you will have a
problem trying to get the housing out. Let the bulb cool, then use your fingers or a special
bulb remover

Question 36

If the bulb contacts become corroded, one may remedy this problem by unplugging
the instrument and:
a) replacing the contacts
b) wiping the contacts with alcohol
c) scraping with a metal file
d) blowing with compressed air

Answer 36

c) The only way to remove corrosion is to scrape it off. Alcohol or air will not work.

Question 37

The projector bulb has a build-up of oxidation on one side, decreasing its illumination.
You should:
a) replace the bulb
b) turn the bulb 180 degrees to use the other side (without the build-up)
c) remember that nothing needs to be done as long as all patients are checked in the same
illumination
d) scrape off the contacts in the bulb housing

Answer 37

b) Turn the bulb around to the side that does not have oxidation on it—this is certainly more
cost-effective than changing the bulb. Of course, you can only do this once! When the other half gets grimy, you will have to replace the bulb.

Question 38

Which is true of rechargeable batteries and recharging units?
a) the battery will last 10 years or more
b) the rechargers cannot be left on indefinitely
c) batteries can lose the ability to recharge
d) all batteries can be installed in either direction

Answer 38

c) Rechargeable NiCad batteries have a “memory” and can lose their rechargeable attribute. This is not a problem with lithium ion batteries. The other answers are false.

Question 39

An instrument operating on rechargeable NiCad batteries:
a) should be placed in the charger after each use during the day
b) should be placed in the charger only at the end of the day
c) will not operate if more than 25 feet away from the charger
d) works best if the batteries are cooler than room temperature

Answer 39

b) Because of the NiCad battery’s “memory” (mentioned in answer 38), a rechargeable
instrument should be placed in the charger only at the end of the working day, not after each use

Question 40

Regular cell batteries should be stored:
a) in a heated room
b) in the refrigerator
c) in the freezer
d) at room temperature

Answer 40

d) Store extra batteries at room temperature. Chilling them used to be recommended, but
that no longer applies to modern batteries.

Question 41

If a particular fuse repeatedly burns out, one should:
a) replace the fuse as needed
b) use a fuse with a lower ampere (AMP) rating
c) get professional assistance
d) replace the instrument

Answer 41

c) An instrument that continuously blows fuses is in need of professional repair

Question 42

Match the instrument image on the following pages with its name:
*direct ophthalmoscope
*indirect ophthalmoscope
*retinoscope
*lensmeter (lensometer)
*perimeter
*tangent screen
*phoroptor (refractor)
*slit lamp (biomicroscope)
*ultrasound (A-scan)
*keratometer (ophthalmometer)
*trial lens set
*Schiøtz tonometer
*Goldmann tonometer
*muscle light

Answer 42

H: direct ophthalmoscope
C: indirect ophthalmoscope
D: retinoscope
I: lensmeter (lensometer)
M: perimeter
A: tangent screen
G: phoroptor (refractor)
L: slit lamp (biomicroscope)
F: ultrasound (A-scan)
B: keratometer (ophthalmometer)
J: trial lens set
K: Schiøtz tonometer
N: Goldmann tonometer
E: muscle light

Question 43

One might adjust the concave mirror in an acuity projector in order to:

a) change the size of the letters to fit a shorter room
b) increase the clarity of the letters
c) improve faulty illumination
d) change the place where the target is projected

Answer 43

c) Adjust the mirror to improve illumination. The other 3 items are done by adjusting the
lens or location of the projector.

Question 44

To calibrate the size of the target of an acuity projector, one must:

a) have a 20-foot test distance
b) use a template and adjust the projection tube until the letter fits into the correct bracket
c) use a table to convert every patient’s measurement if the test distance is not 20 feet
d) use a template, and adjust the concave mirror until the letter fits into the correct bracket

Answer 44

b) A template is available to adjust the target to the appropriate size. Move the projection
tube until the letter fits the template.

Question 45

If the vertical alignment of an indirect ophthalmoscope is misaligned:

a) adjust the headband
b) make sure the mirror is clean
c) adjust the mirror
d) have the instrument professionally serviced

Answer 45

d) Improper vertical alignment in an indirect ophthalmoscope must be adjusted by a professional. If the vertical alignment is off, the examiner will have double vision or trouble fusing the images.

Question 46

A bent, or C-shaped streak in a streak retinoscope is caused by:
a) a weak bulb
b) a bent bulb filament
c) a weak battery
d) using it with the sleeve down

Answer 46

b) A bent bulb filament will cause the retinoscope streak to be distorted. (This is caused by lying the instrument on its side.)

Question 47

During a normal workday, when not in immediate use, the retinoscope should be
stored:
a) by lying it on its side on the table
b) by leaving it turned on
c) by placing it upright
d) by lying it in a protected drawer

Answer 47

c) The retinoscope should be placed upright to prevent the filament from distorting.

Question 48

If the retinoscope light flickers and the bulb placement is solid, the flickering is probably due to:
a) a loose bulb filament
b) inadequate charge
c) internal wiring problems
d) weak batteries

Answer 48

c) A flickering light, when the bulb is seated properly, is usually due to internal wiring
problems

Question 49

Which of the following is not true regarding fluid-filled ultrasound probes?

a) the membrane tip is fragile and lasts only a few days
b) the probe is filled with sterile saline solution
c) air bubbles must be removed from the probe before use
d) the crystal in the probe can lose sensitivity over time

Answer 49

b) Water-filled probes contain distilled water, not saline solution

Question 50

Ultrasound units are calibrated by:

a) touching the probe to a test block specific for that machine
b) touching the probe to a flat surface
c) routinely measuring the same person’s eye as a standard
d) pressing the calibration button on the instrument

Answer 50

a) The test block supplied with an ultrasound unit is specific for that instrument.

Question 51

Care of the noncontact tonometer includes all of the following except:

a) firing it at the beginning of each day to blow dust from the air nozzle
b) checking calibration by firing the air burst against your finger
c) covering it when not in use
d) cleaning the objective lens and aperture

Answer 51

b) Calibration in the noncontact tonometer is done by simply firing the machine. No finger
necessary!

Question 52

The muscle light (transilluminator) might require the following maintenance:

a) brightness calibration
b) bulb and battery replacement
c) sterilization
d) tip and casing replacement

Answer 52

b) The muscle light usually runs on batteries (often rechargeable) and will occasionally
blow a bulb. The tip might require disinfection (not sterilization) with an alcohol swab (if
applied directly to the sclera for transillumination, for example).