UNIT 5: Ch 19 (Porth's 5th Ed) - Disorders of Visual Function

Question 1

1. A care aide at a long-term care facility has informed a resident physician that an
   80-year-old woman’s eyes appear to be inflamed and that her eyelids are caked with
   sticky secretions. The woman has been subsequently diagnosed with posterior
   blepharitis. Which of the following treatments is the physician likely to initiate?
   A) Surgical repair of the woman’s blocked meibomian glands
   B) Warm compresses to be applied regularly to her eyes in addition to oral antibiotics
   C) Regularly scheduled cleansing of the woman’s eyes with normal saline
   D) Intravenous steroids coupled with topical antibiotic ointment

Answer 1

Ans: B
Feedback:
Treatment of posterior blepharitis is determined by associated conjunctival and corneal
changes. Initial therapies can include warm compressing of the lids and use of flaxseed
or fish oil tablets to provide omega-3 fatty acid benefits to meibomian oil secretions.
Long-term, low-dose systemic antibiotic therapy guided by results of bacterial cultures
along with short-term topical steroids may also be needed.

Question 2

2. The father of a third grade girl has brought his daughter to a walk-in clinic because he
   believes the girl has pink eye, which has been going around the students in her class.
   The nurse at the clinic concurs with the father’s suspicion of conjunctivitis. Which
   follow-up explanation by the nurse is most accurate?
   A) “The insides of her eyelids have become infected. This often produces severe
   discomfort.”
   B) “The surfaces of her eyes have bacteria or a virus established, and it’s important to
   maintain good hand hygiene until it goes away.”
   C) “An antibiotic ointment will likely resolve her infection, but pain control will be
   necessary in the mean time.”
   D) “It’s important to aggressively treat this in children, since damage to her sight can
   result if it’s not treated.”

Answer 2

Ans: B
Feedback:
Conjunctivitis often spontaneously resolves. The pain associated with conjunctivitis
usually produces only mild discomfort compared with severe discomfort associated with
corneal lesions or deep and severe pain associated with acute glaucoma. Conjunctivitis
may spread to other family members. The corneal surface is not primarily involved, and
pain that is severe suggests corneal involvement rather than conjunctivitis. Sight damage
is not likely to result.

Question 3

3. A 32-year-old man is complaining of burning, itching, photophobia, and severe pain in
   his right eye after swimming in the ocean. To determine that the eye condition was a
   corneal rather than a conjunctival disease, which of the following would be the
   distinguishing symptom?
   A) Burning
   B) Itching
   C) Photophobia
   D) Severe pain

Answer 3

Ans: D
Feedback:
While burning, itching, and photophobia are all important symptoms of conjunctivitis,
severe pain suggests corneal rather than conjunctival disease.

Question 4

4. A 30-year-old woman has sought care because of her recurrent photophobia, tearing,
   and eye irritation. During assessment, her care provider asks about any history of cold
   sores or genital herpes. What is the rationale for the care provider’s line of questioning?
   A) Herpes simplex virus (HSV) conjunctivitis indicated a need for antiviral rather
   than antibacterial treatment.
   B) HSV infection of the cornea is a common cause of corneal ulceration and
   blindness.
   C) Chronic viral infection of the eyes can result in HSV autoinoculation of the mouth
   and labia.
   D) A history of HSV with eye irritation is suggestive of glaucoma.

Answer 4

Ans: B
Feedback:
Herpes simplex virus (HSV) keratitis (not conjunctivitis) with stromal scarring is the
most common cause of corneal ulceration and blindness in the Western world.
Autoinoculation from the eyes to other sites is not common, and glaucoma is not noted
to be a consequence or symptom of HSV infection.

Question 5

5. Which of the following preoperative teaching points related to corneal transplantation is
   most justified?
   A) “You should know that there is a significant risk that your body will reject the
   transplant.”
   B) “The cornea is highly vascular, and therefore you will be at risk for hemorrhage.”
   C) “Your new cornea would come from someone who has recently died.”
   D) “You run a risk of developing a major inflammatory response post-op and will
   need frequent follow-up appointments.”

Answer 5

Ans: C
Feedback:
Advances in ophthalmologic surgery permit corneal transplantation using a cadaver
cornea. The low rejection rate is due to several factors: the cornea is avascular, which
limits perfusion by immune elements; major histocompatibility complexes are virtually
absent in the cornea; antigen-presenting cells are not present in great numbers; the
cornea secretes immunosuppressive factors; and corneal cells secrete substances that
protect against apoptosis, thereby minimizing inflammation.

Question 6

6. Stepping out of a mall and into the sunshine has caused a man’s pupils to constrict. Place
   the following anatomical components of the man’s pupillary reflex in the ascending
   chronological order that they responded to the light. Use all the options.
   A) Oculomotor nuclei
   B) Retinal ganglionic cells
   C) Preganglionic neurons
   D) Pretectal nuclei

Answer 6

Ans: B, D, C, A
Feedback:
Pretectal areas on each side of the brain are connected, explaining the binocular aspect
of the light reflex. The afferent stimuli for pupillary constriction arise in the ganglionic
cells of the retina and are transmitted to the pretectal nuclei at the junction of the
thalamus and the midbrain and from there to preganglionic neurons in the oculomotor
(CN III) nuclei via the pretectooculomotor tract.

Question 7

7. During a physical exam, the nurse practitioner notes that the patient’s optic disk is very
   pale with a larger size/depth of the optic cup. At this point, they are thinking the patient
   may have
   A) glaucoma.
   B) diabetes retinopathy.
   C) macular degeneration.
   D) retinal tear.

Answer 7

Ans: A
Feedback:
The normal optic disk has a central depression called the optic cup. With progressive
atrophy of axons caused by increased intraocular pressure, pallor of the optic disk
develops, and the size and depth of the optic cup increase. Diabetes retinopathy, macular
degeneration, nor retinal tear has these clinical manifestations.

Question 8

8. A 46-year-old male has presented to the emergency department because of the eye pain,
   severe headache, and blurred vision that have followed an eye exam at an optometrist’s
   office earlier in the day. The client tells the triage nurse that he received eye drops
   during the exam “to keep my pupils wide open.” What differential diagnosis will the
   care team first suspect?
   A) Infectious conjunctivitis
   B) Keratitis
   C) Corneal trauma
   D) Angle-closure glaucoma

Answer 8

Ans: D
Feedback:
Symptoms of acute angle-closure glaucoma are related to sudden, intermittent increases
in intraocular pressure. These occur after prolonged periods in the dark, emotional
upset, and other conditions that cause extensive and prolonged dilation of the pupil.
Administration of pharmacologic agents such as atropine that cause pupillary dilation
(mydriasis) also can precipitate an acute episode of increased intraocular pressure in
persons with the potential for angle-closure glaucoma. Attacks of increased intraocular
pressure are manifested by ocular pain and blurred or iridescent vision. The man’s
symptomatology is not characteristic of conjunctivitis, corneal trauma, or keratitis.

Question 9

9. While working at the triage desk in the local emergency department, which of the
   following patients is likely having a medical emergency and needs to be seen first?
   A) A 17-year-old high school student who has a red, itchy eye
   B) A 55-year-old truck driver complaining of sudden onset of ocular pain and blurred
   vision
   C) A 45-year-old school teacher complaining of a red eye that is draining yellow
   secretions
   D) An infant with red eyes who is irritable and refusing to eat

Answer 9

Ans: B
Feedback:
Attacks of increased intraocular pressure are manifested by ocular pain and blurred
vision caused by corneal edema. Acute angle-closure glaucoma is an ophthalmic
emergency. Treatment is directed at reducing the intraocular pressure, usually with
pharmacologic agents.

Question 10

10. If the anterior–posterior dimension of the eyeball is too long, the focus point for an
    infinitely distant target is anterior to the retina. This patient would be diagnosed as
    having
    A) hyperopia.
    B) myopia.
    C) cycloplegia.
    D) presbyopia

Answer 10

Ans: B
Feedback:
If the anterior–posterior dimension of the eyeball is too long, the focus point for an
infinitely distant target is anterior to the retina. This condition is called myopia or
nearsightedness. People with myopia can see close objects without problems. Hyperopia
is farsightedness. Cycloplegia is paralysis of the ciliary muscle, with loss of
accommodation. Presbyopia refers to a decrease in accommodation that occurs because
of aging.

Question 11

11. Which of the following individuals would be considered at high risk for developing
    cataracts? Select all that apply.
    A) An 88-year-old female with osteoporosis and congestive heart failure
    B) A 51-year-old female whose rheumatoid arthritis is controlled with oral
    corticosteroids
    C) A 50-year-old male who takes nebulized bronchodilators four times daily for the
    management of his emphysema
    D) A 39-year-old woman with a history of open-angle glaucoma and poorly
    controlled diabetes
    E) A 29-year-old artist who spends long hours in sunlight painting landscapes

Answer 11

Ans: A, B, D, E
Feedback:
Advanced age, steroid use, and sunlight exposure are all significant risk factors for the
development of cataracts. Metabolically induced cataracts are caused by disorders of
carbohydrate metabolism (diabetes). Use of bronchodilators is not noted to be strongly
associated with cataracts.

Question 12

12. A 37-year-old male has survived a logging accident in which the severing of his femoral
    artery and consequent blood loss resulted in cardiogenic shock. On recovery, one of the
    deficits that he finds most frustrating is a significant loss of visual acuity. Which is the
    most likely rationale for his vision damage?
    A) Decreased cerebral perfusion results in progressive damage to the optic nerve.
    B) Circulatory collapse causes rapid death of retinal neurons.
    C) Lack of oxygen results in a distortion of the fovea.
    D) The visual cortex is susceptible to hypoxic necrosis

Answer 12

Ans: B
Feedback:
Acute decreased circulation can result in sight damage from edema and death of retinal
neurons. Damage to the optic nerve, the fovea, and the visual center are not likely to be
contributing factors

Question 13

13. Which of the following patients would be considered high risk for developing
    papilledema? Select all that apply.
    A) A 2-year-old patient who has a shunt placed following delivery where he was
    diagnosed with hydrocephalus
    B) A 55-year-old male with substernal chest pain radiating down both arms and
    experiencing nausea
    C) A 43-year-old male with diabetes, renal insufficiency, and BP 200/107
    D) A 25-year-old motorcyclist who was in an accident and has a potential subdural
    hematoma
    E) An 18-year-old female complaining of severe cramps with her menstrual bleeding

Answer 13

Ans: A, C, D
Feedback:
The most common conditions causing increased intracranial pressure include cerebral
tumors, subdural hematoma, hydrocephalus, and malignant hypertension. Possible MI is
not one of the causes of increased intracranial pressure.

Question 14

14. A 31-year-old female has been recently diagnosed with type 2 diabetes mellitus and is
    attending a diabetes education class. Which of the following statements by the woman
    demonstrates an accurate understanding of her health problem?
    A) “I’ll have to control my blood sugars, my blood pressure, and my cholesterol in
    order to make sure I don’t develop sight problems.”
    B) “I’m grieving the fact that I won’t be able to get pregnant without causing
    permanent damage to my vision
    C) “It’s surprising that sugar in my blood can accumulate on the lens of my eye and
    cause a loss of sight.”
    D) “I want to avoid going through the treatments for sight restoration that I would
    need if my diabetes causes damage to my vision.”

Answer 14

Ans: A
Feedback:
The threat to vision that is posed by poorly controlled blood sugar levels is compounded
by high blood pressure and/or cholesterol levels. Pregnant women with diabetes need
additional care to monitor their sight, but they will not necessarily lose it. The damage
caused by diabetes does not occur on the lens, and restoration of lost visual acuity is not
normally possible.

Question 15

15. A college junior calls his mother, a nurse, complaining of “not being able to see.” When
    questioned further, he describes, “A gray curtain just went down my right visual field. I
    don’t know what to do.” The nurse should recognize this symptom as which of the
    following conditions and have her teenager go to the emergency department
    immediately.
    A) Glaucoma
    B) Strabismus
    C) Retinal detachment
    D) Macular degeneration

Answer 15

Ans: C
Feedback:
The primary symptom of retinal detachment consists of painless changes in vision.
Commonly, flashing lights or sparks, followed by small floaters or spots in the field of
vision, occur as the vitreous pulls away from the posterior pole of the eye. As
detachment progresses, the person perceives a shadow or dark curtain progressing
across the visual field.

Question 16

16. A public health nurse is teaching a health promotion class to a group of older adults at a
    seniors’ center. A woman attending states that, “My husband has got dry macular
    degeneration, and I don’t know what we’re going to do when he goes blind from it.”
    How can the nurse best respond to the woman’s statement?
    A) “Vitamins C and E as well as zinc and beta carotene may have some value in
    slowing the progression of his disease
    B) “You should talk to your doctor about the surgical options that might help
    preserve his sight.”
    C) “If your husband can lower his blood pressure and bad cholesterol, it can possibly
    slow the progression of his disease.”
    D) “Cataract surgery is showing promise as a way of replacing the part of the eye
    associated with macular degeneration.”

Answer 16

Ans: A
Feedback:
Vitamin E, vitamin C (ascorbic acid), zinc, and beta carotene have shown promise at
slowing the progression of the age-related macular degeneration in persons with the
disease. Surgical options are not normally available for the dry variety of macular
degeneration. Blood pressure control, cholesterol control, and cataract surgery are
unlikely to be directly useful.

Question 17

17. A patient has sought medical attention because of a loss of different half-fields in the
    two eyes. Knowing the potential causes of this complaint, the nurse anticipates that the
    physician will order tests looking for
    A) metal fragments in the eyes.
    B) hemorrhages in the capillaries of both eyes.
    C) an enlarging pituitary tumor.
    D) subarachnoid hemorrhage.

Answer 17

Ans: C
Feedback:
Enlarging pituitary tumors can produce longitudinal damage through the optic chiasm
with loss of medial fibers of the optic nerve representing both nasal retinas and both
temporal visual half-fields. The loss of different half-fields in the two eyes is called a
heteronymous loss. Metal fragments can get in the eye from welding. Hemorrhages in
both eyes have numerous causes like uncontrolled hypertension and diabetes.
Subarachnoid hemorrhages are usually trauma related.

Question 18

18. As the eyes rotate upward, the upper eyelid reflexively retracts. Which cranial nerve is
primarily responsible for this response?
A) Cranial nerve I
B) Cranial nerve III
C) Cranial nerve VI
D) Cranial nerve IV

Answer 18

Ans: B
Feedback:
The CN III (oculomotor) nucleus, which extends through a considerable part of the
midbrain, contains clusters of lower motor neurons for each of the five eye muscles it
innervates. Because of its plane of attachment, the inferior oblique rotates the eye in the
frontal plane pulling the top of the eye laterally. In other words, as the eyes rotate
upward, the upper eyelid is reflexively retracted, and in the downward gaze, it is
lowered, restricting exposure of the conjunctiva to air and reducing the effects of drying.
CN I is involved in olfactory function; CN VI (abducens nerve) innervates the lateral
rectus, which abducts the eye. CN IV (trochlear nerve) innervates the superior oblique
muscle, which depresses, rotates laterally, and intorts the eyeball.

Question 19

19. A 4-month-old infant and his mother are at an appointment with a pediatrician to follow
    up his nonaccommodative strabismus and to determine a treatment plan. Which of the
    following treatments is most likely to prevent future loss of vision?
    A) Prescribing glasses once the infant is 6 months of age
    B) Use of beta-adrenergic blockers and latanoprost eye drops
    C) Regularly scheduled eye exams and monitoring of self-correction of his eyes
    D) Surgical correction of the musculature

Answer 19

Ans: D
Feedback:
Strabismus is ideally treated by surgery rather than with glasses in the case of infants.
The condition will not resolve independently, and medications are unlikely to help the
condition.

Question 20

20. A 3-year-old girl has been diagnosed with amblyopia. Which of the following
    pathophysiological processes is most likely to underlie her health problem?
    A) The child may have a congenital deficit of rods and/or cones.
    B) The girl may have chronic bacterial conjunctivitis.
    C) She may have been born with infantile cataracts.
    D) The child may have a neural pathway disorder.

Answer 20

Ans: C
Feedback:
There are multiple potential causes of amblyopia, including cataracts. A deficit of rods
or cones, a neural pathway disorder, and chronic conjuctivitis are not noted to be
common precursors.