1. EYE AND EAR ASSESSMENT AND PROCEDURES
CHAPTER 6
EYE AND EAR ASSESSMENT AND PROCEDURES

2. PRETEST
True or False
The outer layer of the eye is composed of white connective tissue known as the sclera.
A person who is farsighted has a condition known as myopia.
An optometrist can perform eye surgery.
The Snellen eye test is conducted at a distance of 20 feet.
The eustachian tube connects the nasopharynx to the inner ear.

3. PRETEST, CONT. True or False
An eye instillation may be performed to treat an eye infection.
The function of cerumen is to inhibit the growth of pathogens.
The most specific type of hearing test is the tuning fork test.
Serous otitis media can result in a conductive hearing loss.
An ear instillation may be performed to treat an ear infection.

4. Content Outline Introduction to Eye and Ear Assessment
MA is responsible for performing a variety of eye and ear assessments and procedures
Visual acuity test: screening test to detect deficiencies in vision
Hearing test: use of tuning fork or audiometer
Audiometer: instrument that emits sound waves at various frequencies
MA should be alert to signs that indicate the patient might be having difficulty hearing
What are signs that would alert the MA that a patient has a hearing problem?

5. Introduction to Eye and Ear Assessment, cont.
Color vision assessment
Requires specially prepared colored plates
Color blindness: inability to distinguish certain colors
Red and green most common
Why is it important for a person to see red and green colors?

6. Introduction to Eye and Ear Assessment, cont.
Eye and ear irrigations and instillations
Irrigation: washing a body canal with a flowing solution
Instillation: dropping a liquid into a body cavity
Why would we irrigate an eye? 6

7. The Eye Structure of the Eye Eye has three layers: Sclera: outer layer
Composed of tough, white, fibrous connective tissue
Front of sclera is modified to form cornea
Cornea: transparent covering over the colored part of the eye
What is a corneal abrasion? 7

8. Structure of the Eye
From Applegate EJ: The anatomy and physiology learning system, ed 2, Philadelphia, 2000, Saunders.

9. Structure of the Eye, cont.
Choroid: middle layer
Composed of many blood vessels and is highly pigmented
Blood vessels: nourish the eye
Pigment: absorbs stray light rays
Front part of choroid specialized into:
Ciliary body: muscles that control shape of the lens
Suspensory ligaments: suspend lens in place
Lens: focuses light rays on the retina
Can we see the choroid just by looking at a person’s eye? 9

10. Structure of the Eye, cont.
Iris: colored part of the eye that controls size of the pupil
Pupil: opening in the eye that permits entrance of light rays
Retina: inner layer
Light rays come to a focus on the retina
Transmitted to brain by optic nerve to be interpreted
Define retinal detachment. 10

11. Structure of the Eye, cont.
Chambers of the eye
Anterior chamber: area between cornea and iris
Posterior chamber: area between iris and lens
Aqueous humor: fills both anterior and posterior chambers
Vitreous humor: transparent jellylike material
Fills eyeball between lens and retina
Function: maintains the shape of the eyeball
See slide 8 for structure. 11

12. Structure of the Eye, cont.
Conjunctiva: membrane that lines eyelids and covers front of the eye, except for the cornea
Conjunctiva covering the sclera: transparent
Allows white sclera to show through
See slide 8 for structure. 12

13. Visual Acuity Visual acuity: acuteness or sharpness of vision
Normal visual acuity:
Can see clearly
Able to distinguish fine details
Both close up and at a distance
Normal visual acuity is 20/20. 13

14. Errors of Refraction
Errors of refraction: most common cause of defects in visual acuity
Refraction: bending of the parallel light rays coming into the eye so they can be focused on the retina
Notice the point of focus on the slide.

15. Errors of Refraction, cont.
Error of refraction: light rays are not being bent properly:
Are not focused on retina adequately
Cause: defect in the shape of eyeball
Can be improved with corrective lenses
What are the types of lenses available for a patient?
Is there a corrective surgery available for errors of refraction? 15

16. Myopia Myopia (nearsighted): eyeball too long from front to back
Causes light rays to focus in front of retina
Difficulty seeing objects at a distance
May squint and have HA from eye strain
Corrective lenses (eyeglasses, contact lenses) or laser surgery: can correct condition
Cause light rays to focus on retina
In school children, what is another problem they may have besides squinting? 16

17. Myopia, cont.
Notice the point of focus.

18. Hyperopia Hyperopia (farsighted): eyeball too short from front to back
Causes light rays to focus behind the retina
Difficulty viewing objects at a reading or working distance
May have blurring, headache, and eye strain while performing close-up tasks
Corrective lenses can correct condition
Cause light rays to focus on retina
A convex plus lens is used in corrective glasses. 18

19. Hyperopia, cont.
Notice the point of focus.

20. Presbyopia Presbyopia: decrease in elasticity of lens
Usually begins after age 40
Results in a decreased ability to focus clearly on close objects
Are corrective lenses used for this condition? 20

21. Eye Specialists Types of eye specialists
Ophthalmologist: medical doctor specializing in diagnosis and treatment of diseases and disorders of the eye
Prescribes ophthalmic and systemic medications
Performs eye surgery
List one type of eye surgery. 21

22. Eye Specialists, cont.
Optometrist: licensed primary health care provider who has expertise in measuring visual acuity and prescribing corrective lenses
Can diagnose and treat of disorders and diseases of the eye
Prescribes ophthalmic medications
Not a physician: cannot prescribe systemic medications or perform eye surgery
Optician: professional who interprets and fills prescription for eyeglasses and contact lenses
What is a systemic medication? 22

23. Assessment of Distance Visual Acuity (DVA)
Used to diagnose myopia
Along with other tests
Snellen eye chart: most often used 23

24. Assessment of Distance Visual Acuity (DVA), cont.
Types of charts
Letters in decreasing sizes
Used for school-aged children and adults
The MA should explain the test to the patient before the procedure.

25. Assessment of Distance Visual Acuity (DVA), cont.
Capital letter E in decreasing sizes (arranged in different directions)
Used for preschool children, non-English-speaking people, nonreaders
Pictures of familiar objects
Used for preschoolers
Less accurate because some children are unable to identify objects
How would the patient explain to us what direction the E is facing? 25

26. Snellen Big E Chart

27. Conducting a Snellen Test
Perform in a well-lit room free from distractions
Performed at a distance of 20 feet
Mark off with paint or tape on floor
Why would we use a well-lit area?
Why would we perform this test at 20 feet away? 27

28. Conducting a Snellen Test, cont.
Two numbers next to each row of letters
Number above line: distance at which test is conducted (20 feet)
Number below line: distance from which a person with normal visual acuity can read the row of letters
Normal DVA: 20/20
Person can read what supposed to read at 20 feet
How would we explain 20/25? 28

29. Conducting a Snellen Test, cont.
DVA: 20/30
Smallest line the individual could read at 20 feet
People with normal acuity can read this line at 30 feet
DVA: 20/15
Indicates above-average DVA
People with normal acuity can read at 15 feet 29

30. Conducting a Snellen Test, cont.
Acuity of each eye measured separately
Traditionally beginning with right eye
If patient wears eyeglasses or contact lenses (except reading glasses)
Keep them on during test
Record in chart that corrective lenses were worn
Also record if corrective lenses were not being worn
How would you chart if corrective lenses were worn? 30

31. Snellen Eye Test

32. Conducting a Snellen Test, cont.
Eye occluder: held over eye not being tested
Patient's hand should not be used; may encourage peaking through fingers
Instruct patient to leave eye not being tested open
Closing eye: causes squinting of eye being tested
What would the MA use to clean the eye occluder?
What does squinting do to our vision temporarily? 32

33. Conducting a Snellen Test, cont.

34. Snellen Eye Chart

35. Assessing Distance Visual Acuity in Preschoolers
Snellen Big E chart used
Completely explain procedure to child
Tell child you will be playing a pointing game
Do not force child: results will be inaccurate
How would we communicate with a child who is too shy and refuses to perform the exam? 35

36. Assessing Distance Visual Acuity in Preschoolers, cont.
Draw a capital E on an index card
Teach child to point in the direction of the open part of the E
Phrases to describe open part of E: "fingers" or "legs of table"
Allow child to practice
Praise child when correct
Parent may need to help child hold occluder in place
Some offices give the child an award such as a sticker when the test is complete. 36

37. Snellen Big E Chart

38. What Would You Do? What Would You Not Do?

39. What Would You Do? What Would You Not Do?

40. Assessment of Near Visual Acuity (NVA)
Assesses patient's ability to read objects close up
Used to detect hyperopia and presbyopia
NVA card: contains different sizes of type:
Ranging from size of newspaper headline down to very small print
The physician may order a visual acuity test if there has been an injury to the eye. 40

41. Assessment of Near Visual Acuity (NVA)
Available in variety of forms:
Printed paragraphs
Printed words
Pictures
Which one would you use for a child? 41

42. Assessment of Near Visual Acuity (NVA), cont.
To perform NVA testing:
Perform test in well-lit room free of distractions
Patient holds card at a distance of 14 to 16 inches
Reading glasses should be worn (if patient uses them)
Each eye tested separately
Why would the patient keep the reading glasses on for this test? 42

43. Assessment of Near Visual Acuity (NVA), cont.
To perform NVA testing, cont.:
Eye occluder held over eye not being tested
Instruct patient to keep covered eye open
Closing causes squinting of eye being tested
Patient asked to read each line or paragraph
If the patient fails the NVA test, where would we refer the patient? 43

44. Assessment of Near Visual Acuity (NVA), cont.
Observe patient for unusual symptoms
Squinting, tilting of head, watering of eyes
Indicates patient having difficult reading card
Patient continues until reaching smallest line that can be read
How would you chart the symptoms observed? 44

45. Assessment of Near Visual Acuity (NVA), cont.
Record results as smallest type patient could read with each eye
Recording based on type of test card used
Also record:
Date and time
If corrective lenses worn
Unusual symptoms exhibited by patient 45

46. Near Visual Acuity Chart

47. Assessment of Color Vision
Classification of defects in color vision:
Congenital defect: most common
Inherited (present at birth)
Most often affects males
Acquired defect: acquired after birth
Eye injury
Disease
Certain drugs
Retinal disease or optic nerve disease may cause color vision. 47

48. Assessment of Color Vision, cont.
Color vision tests detect congenital color vision defects
Often performed in medical office
Basic color vision screening test:
Ask patient to identify red and green lines on Snellen chart
How would you ask the patient to identify lines? 48

49. Ishihara Test Detects:
Total congenital color blindness
Red-green color blindness
Series of plates: colored dots forming a numeral against a background of dots of contrasting colors
Patients with normal color vision: read appropriate numeral
How would you explain to the patient how to perform the test? 49

50. Ishihara Color Plates Identify the numbers in the circles.
From Ishihara J: Tests for color blindness, Tokyo, 1920, Kanehara.

51. Ishihara Test, cont. Patients with defects read dots as:
Not forming a number at all
Forming a different number 51

52. Ishihara Test, cont. First plate can be read correctly by all patients
Used to explain test procedure to patient
Plates with winding colored lines:
For patients unable to identify numbers by name
Patient asked to trace line formed by the dots
Used for preschoolers and non-English-speaking persons
Patients should use a cotton-tipped applicator instead of their finger to trace the lines. 52

53. Ishihara Test, cont. Conduct test in quiet room
Illuminated by natural daylight
Bright sunlight can change shades of color on plates
Can cause inaccurate test results
Can use electric light
Should adjust to resemble natural daylight
Some offices have natural daylight light bulbs for this purpose. 53

54. Ishihara Test, cont.

55. Ishihara Test, cont. Test consists of 14 color plates:
Basic test: Plates 1-11
Further assessment of patient's with red-green deficiency: Plates 12, 13, and 14
From Ishihara J: Tests for color blindness, Tokyo, 1920, Kanehara. 55

56. Ishihara Test, cont. Interpretation of results
Normal color vision: 10 or more plates read correctly
Color vision deficiency: 7 or fewer plates read correctly
Defect in color vision: patient referred to ophthalmologist or optometrist
For additional assessment
Use of more precise color vision tests
How would you chart the results? 56

57. Eye Irrigation Washing the eye with a flowing solution Purpose
Cleanse the eye by washing away:
Foreign particles
Ocular discharges
Harmful chemicals
Relieve inflammation though application of heat
Apply an antiseptic solution
For what types of foreign particles might we irrigate? 57

58. Eye Irrigation, cont.

59. Eye Instillation Dropping of a liquid into lower conjunctival sac
Purpose
Treat eye infections (with medications)
Soothe an irritated eye
Dilate the pupil
Anesthetize during eye examination or treatment
Describe where the lower conjunctival sac is. 59

60. Eye Instillation, cont.
Locate the conjuctival sac.

61. Eye Instillation, cont.
Medications instilled in eye may come in the form of:
Liquid (ophthalmic drops)
Usually dispensed in a flexible bottle with an attached dropper
Ointment
Dispensed in a small metal tube with tip for applying medication
The tip of the medication should not come in contact with the eye.
Give examples of ophthalmic medications. 61

62. What Would You Do? What Would You Not Do?

63. What Would You Do? What Would You Not Do?

64. The Ear Structure of the Ear
Functions in hearing and maintaining equilibrium
Consists of three divisions:
External ear
Auricle (pinna): flap of cartilage covered with skin that
Projects from side of head
Receives and collects sound waves and directs them toward the external auditory canal
What is equilibruim?
Can we still hear without an auricle? 64

65. Structure of the Ear, cont.
External auditory canal: extends from auricle to tympanic membrane
Also known as external ear canal
External auditory meatus: opening of canal
1 inch long in adult
Lined with skin that contains nerve endings, fine hairs, glands
Glands secrete cerumen: lubricates and protects ear canal
Can we have too much cerumen in our ears?
Can we have too little cerumen in our ears? 65

66. Structure of the Ear, cont.
Canal has an S-shaped curve as it leads inward
Canal must be straightened during:
Tympanic membrane: located at end of the canal
Pearly gray semitransparent membrane
Receives sound waves
Otoscopic examination
Ear instillation
Ear irrigation
Aural temperature measurement
You should not clean your ears with a cotton-tipped applicator. This could puncture the tympanic membrane. 66

67. Structure of the Ear, cont.
From Applegate EJ: The anatomy and physiology learning system, ed 2, Philadelphia, 2000, Saunders.

68. Structure of the Ear, cont.
Middle ear: air-filled cavity
Contains three small bones (ossicles)
Malleus
Incus
Stapes
Eustachian tube: connects middle ear to the nasopharynx
Stabilizes air pressure between the external atmosphere and the middle ear
If a patient has a eustachian tube dysfunction, it may cause dizziness. 68

69. Structure of the Ear, cont.
Inner ear
Cochlea: essential organ of hearing
Semicircular canals: maintain equilibrium
Cochlear implants are used for deaf and severely hard-of-hearing patients. 69

70. Assessment of Hearing Acuity
Part of complete PE
Person can have hearing loss and not be aware of it
Early detection and treatment: may prevent permanent hearing loss
If a patient is not aware of the problem, usually a family member recognizes it. 70

71. Assessment of Hearing Acuity
Person with normal hearing: can hear frequencies of normal speech
Ranges from 300 to 4000 Hz (hertz or cycles per second)
Patients who exhibit hearing loss:
a. Referred to otolaryngologist or audiologist
ENT stands for ear, nose, and throat. 71

72. Conductive Hearing Loss
Conductive hearing loss: results when there is a physical interference with normal conduction of sound waves through external and middle ear
Most common type of hearing loss
Amount of sound reaching inner ear is less than normal
What is prescribed for hearing loss? 72

73. Conductive Hearing Loss, cont.
Conductive loss in external ear
Caused by an obstruction of external ear canal:
Impacted cerumen
External otitis (swimmer's ear)
Foreign bodies
Benign growths (polyps)
What is ordered for impacted cerumen? 73

74. Conductive Hearing Loss, cont.
Conductive loss in middle ear
Caused by an obstruction in middle ear:
Serous otitis media (fluid in middle ear)
Acute otitis media (infection in middle ear)
Perforated tympanic membrane
Otosclerosis
What could be prescribed for acute otitis media? 74

75. Conductive Hearing Loss, cont.
Cause of conductive loss: often detected by examining the ear canal with otoscope
Hearing frequently restored by:
Removing obstruction (e.g., cerumen)
Treating the disorder (e.g., serous otitis media)
A disposable speculum is used when examining the ear with an otoscope to prevent cross-contamination. 75

76. Sensorineural Hearing Loss
Sensorineural hearing loss: results from damage to inner ear or auditory nerve
Sound is conducted normally through outer and middle ear structures
Problem with perception of sound waves: results in a hearing deficit
Meniere’s disease can cause this type of hearing loss. 76

77. Sensorineural Hearing Loss, cont.
Causes
Hereditary factors
Intense noise exposure over period of time
Tumors
Changes from normal aging process
Ototoxicity caused by certain medications
Infectious diseases (measles, mumps, meningitis)
Mixed hearing loss: combination of both conductive and sensorineural loss
Name some employees that might be exposed to increased intense noise. 77

78. What Would You Do? What Would You Not Do?

79. What Would You Do? What Would You Not Do?

80. Hearing Acuity Tests Include: Simple gross screening test
Qualitative tests: tuning fork
Highly sensitive tests: audiometry 80

81. Hearing Acuity Tests, cont.
Important to test only one ear at a time
Hearing deficit may exist only in one ear
Ear not being tested: blocked by an earplug or masked
Masking: presentation of sound to ear not being tested
So patient's response is based only on hearing in ear being tested
How would you explain the test to the patient? 81

82. Gross Screening Test Gross Screening Test
Used to identify a very large hearing impairment
Whisper test: patient asked to repeat simple word or series of numbers
Whispered from a distance of 1 to 2 feet
If the whisper test is performed, the patient may be asked to plug one ear and then the other. 82

83. Tuning Fork Tests Tuning Fork Tests
Provide a general assessment of hearing acuity
Use of tuning fork with frequency of 512 or 1024 Hz
These frequencies fall within range of normal speech
How would you clean the tuning fork? 83

84. Weber Test Weber test: useful when one ear hears better than other
Fork set in vibration
Base of fork placed on center of patient's head
Patient indicates where sound is heard best
How do you set the fork into vibration? 84

85. Weber Test, cont.

86. Weber Test, cont. Results of Weber test:
Normal hearing: patient hears sounds equally in both ears
Conductive hearing loss: patient hears sound better in problem ear
Sensorineural hearing loss: patient does not hear the sound as well in problem ear
How would we record the results? 86

87. Rinne Test
Rinne test: compares the duration of sound perception by air conduction with that of bone conduction
Fork is set in vibration
Base of fork placed against bone of mastoid process
Patient indicates when sound is no longer heard
Prongs of fork (still vibrating) placed in the air: 1 inch from opening of ear
Where is the mastoid process located? 87

88. Rinne Test, cont.

89. Rinne Test, cont. Results of Rinne test:
Normal hearing: patient hears sound twice as long through air conduction as through bone conduction
Conductive hearing loss: patient hears the sound longer by bone conduction than by air conduction
Sensorineural hearing loss: sound is reduced; patient also hears sound longer through air conduction than through bone conduction, but not twice as long
How would the results be charted? 89

90. Audiometry
Audiometry: measurement of hearing acuity using an audiometer
Audiometer: an instrument that quantitatively measures the various frequencies of sound waves
Provides information on:
How extensive hearing loss is
Which frequencies are involved
How would you explain the procedure to the patient? 90

91. Audiometer
Courtesy GSI [Grayson-Stadler], Milford, NH.

92. Audiometry, cont. To perform test: Conduct test in quiet room
Headphones placed snugly over ears
Each ear assessed separately
Audiometer delivers a single frequency at a time
Starts with low frequencies (250 to 500 Hz) and goes to high frequencies (6000 to 8000 Hz)
Patient signals when sound is heard
Results plotted on a graph (audiogram)
How should the patient signal when the sound is heard? 92

93. Audiometry, cont.
Courtesy GSI [Grayson-Stadler], Milford, NH

94. Tympanometry Tympanometry: helps determine cause of hearing loss
Not a hearing test
Tympanometer: earpiece attached to an electronic device
This is a diagnostic test.
Courtesy GSI [Grayson-Stadler], Milford, NH

95. Tympanometry, cont. Earpiece placed snugly in patient's ear
Low-frequency sound waves are directed against eardrum
While pressure is applied in ear canal
Instruct the patient to remain still and quiet.
Courtesy GSI [Grayson-Stadler], Milford, NH.

96. Tympanometry, cont.
Normal ear: eardrum exhibits mobility in response to pressure
Fluid present in middle ear: eardrum will not move (remains stiff)
Used to diagnose serous otitis media
Common cause of temporary hearing loss in children
Results printed on a graphic readout: tympanogram
Fluid in the middle ear is usually not treated. If infection is present, antibiotics are prescribed. 96

97. Ear Irrigation
Washing of the external auditory canal with a flowing solution
The solution to use is ordered by the physician.

98. Ear Irrigation, cont. Performed to:
Cleanse external ear canal to remove:
Cerumen
Discharge
Foreign body
Relieve inflammation by applying antiseptic solution
Apply heat to ear
When irrigating the ear, the syringe should be inserted toward the roof of the ear to prevent tympanic membrane injury. 98

99. Ear Irrigation, cont.
Impacted cerumen must be softened before removal:
By instilling warm mineral oil or hydrogen peroxide (10 to 15 minutes)
Do not perform irrigation if tympanic membrane is perforated
Could result in severe irritation or infection of middle ear
The ear canal must be straightened to reach all areas of the canal. 99

100. Ear Instillation Dropping of a liquid into the external auditory canal
a. Usually dispensed in a flexible plastic
container with an attached dropper
2. Performed to:
Soften impacted cerumen
Combat infection with antibiotic eardrops
Relieve pain
A moistened cotton wick may be used after instillation. Why would we want to moisten the wick?
100

101. Ear Instillation, cont.
Do not touch the ear with the tip of the applicator if this is a multi-dose bottle. Why would we want to avoid this?

102. POSTTEST
True or False
The function of the lens is to permit the entrance of light rays into the eye.
Visual acuity refers to sharpness of vision.
Presbyopia is a decrease in the elasticity of the lens due to the aging process.
An optician fills prescriptions for eyeglasses.
The Snellen Big E chart is used with school-aged children.

103. POSTTEST, CONT. True or False
The most common color vision defects are congenital in nature.
The cochlea functions in maintaining equilibrium.
The range of frequencies for normal speech is 300 to 4000 Hz.
Intense noise can result in a sensorineural hearing loss.
Tympanometry is used to diagnose patients with auditory nerve damage.