Oculomotor Nerve Palsies

Question 1

What happens in CN III (Oculomotor) Nerve Palsy?

Answer 1

• Ptosis
• May have dilated pupil
• Eye down and out

Question 2

What happens in CN IV (Trochlear) Nerve Palsy?

Answer 2

• Paralysis of superior oblique muscle
• Vertical or Oblique Diplopia
• Subtle findings
• If in doubt, refer to Ophthalmology

Question 3

What happens in CN VI (Abducens) Nerve Palsy?

Answer 3

• Paralysis of lateral rectus muscle
• Affected eye is esotropic(turned in) causing horizontal diplopia
• Movement of affected eye partially or totally limited in lateral gaze
• May be idiopathic

Question 4

What are the eight common causes of red eye?

Answer 4

1. Chemical Injury
2. Angle-closure glaucoma
3. Ocular foreign body
4. Corneal abrasion
5. Uveitis
6. Conjunctivitis
7. Ocular surface disease
8. Subconjunctival hemorrhage

Question 5

What are the sources of chemical keratoconjunctivitis?

Answer 5

1. Any irritating agent - not very bad
2. Bad = Acid injuries
3. Worst = Alkali injuries, continue to burn

Question 6

How should you treat a chemical eye injury?

Answer 6

• Irrigate with normal saline until pH of tears neutralized
• Patch with ophthalmic ointment
• Give drug (cycloplegia - don’t men)
• Refer to ophthalmologist

Question 7

What are corneal abrasion symptoms?

Answer 7

• Foreign body sensation
• Pain
• Tearing
• Photophobia

Question 8

What can help you see corneal abrasions?

Answer 8

Applying fluorescein to the eye

Question 9

What should you do with a corneal laceration?

Answer 9

DO NOT apply drops or ointment and cover with a shield.

Refer immediately.

Question 10

What is hyphema?

Answer 10

Blood pooling in the bottom of the iris

Question 11

What can cause linear abrasions on the cornea?

Answer 11

Metallic body under the upper lid.

Question 12

What are the corneal abrasion treatments and what are their goals?

Answer 12

Goals: 
-Promote rapid healing
-Relieve pain
-Prevent infections
Rx: 
-1% cyclopentolate
-Topical antibiotics (drops or ointments)
-Pressure patch for 24-48 hours
-Oral analgesics

Question 13

What should you NEVER give to someone with an eye injury?

Answer 13

Topical Anesthetics!! They feel great but they prevent healing. Patients will steal these!

Question 14

What are the three most common causes of adult conjunctivitis? What is their discharge like?

Answer 14

• Viral = clear = preauricular (in front of ears) lymphadenopathy
• Bacterial = purulent - often wake up with eyes stuck together and swollen!
• Allergic = watery, with stringy, white mucous - itchy

Question 15

What is the best treatment for bacterial conjunctivitis?

Answer 15

• Clean lids of discharge
• Warm compress
• Topical antibiotic drops (Polymyxin B) or ophthalmic ointment (bacitracin or erythromycin)
• Refer if not improved in 3-4 days

Question 16

What does a viral conjunctivitis look like?

Answer 16

• Watery discharge!
• Often unilateral
• Concomitant URI
• Preauricular adenopathy

Question 17

What are the best ways to treat viral conjuctivitis?

Answer 17

• Very contagious - good hygiene
• No effective therapy but time (2-6 wks)
• Cold compress and artificial tears
• Refer if pain, photophobia, decreased vision

Question 18

What does allergic conjunctivitis look like?

Answer 18

• Diffusion injection
• Often involves lids, usually bilateral
• Longer history, often intermittent
• Little discharge (ropy/stringy, mucoid)

Question 19

What are the best ways to treat allergic conjuctivitis?

Answer 19

• Avoidance
• Cold compress
• Topical/Oral antihistamines
• Topical Mast Cell stabilizer

Question 20

What type of conjunctivitis is it if it’s associated with a URI/

Answer 20

Probably Viral!