Ear

Question 1

Know where the following are with the ear:

• Pinna
• Angled and long ear canal (vertical and horizontal canals)
• Tympanic membrane
• Tympanic bulla

Answer 1

• Just look at a picture and know it

Question 2

What is the primary difference between cats and dogs with the tympanic bullae?

Answer 2

• Cats have a septum that divides the bulla into two compartments

Question 3

Blood supply to the ear

Answer 3

• Lateral, intermediate, and medial auricular arteries

- Medial and lateral auricular vein

Question 4

Blue LO Which are the three parts of the ear? (Fossum has four)

Answer 4

1. Inner ear (membranous and bony labyrinth and functions for hearing and balance)
2. The middle ear, which is formed by the tympanic cavity and connects to the pharynx via the auditory tube (eustachian tube)
3. The external ear, which is formed by the auditory meatus and a short canal
4. The pinna

Question 5

Blue LO What are the two parts of the ear canal?

Answer 5

• Initial vertical canal and a shorter horizontal canal

Question 6

Blue LO Which anatomical structures are connected by the Eustachian tube?

Answer 6

Middle ear and the pharynx

Question 7

Green LO Which surface of the pinna is affected by the aural hematoma?

Answer 7

• Concave surface of the pinna

Question 8

What is an aural hematoma?

Answer 8

• Disruption of the perforating vessels through cartilage of the pinna

Question 9

Green LO What is the proposed cause of aural hematomas?

Answer 9

• Usually secondary to chronic trauma (otitis externa related)
• You must treat the underlying condition with this

Question 10

Green LO What are the three goals of surgery to repair an aural hematoma?

Answer 10

1. Drain hematoma
2. Maintain tissue apposition
3. Retain the natural appearance of the ear (i.e. minimize thickening and scarring)

Question 11

Green LO What is the most common procedure for aural hematoma repair?

Answer 11

• Make an S-shaped incision on the concave surface of the ear and expose the hematoma and its contents from end to end
• Remove the fibrin clot and irrigate the cavity
• Using 2-0 to 3-0 monofilament nonabsorbable suture, place 0.75 to 1-cm long sutures through the skin on the concave surface of the ear and underlying cartilage
• Place the sutures parallel to the major vessels (vertical rather than horizontal)
• Place an ample number of sutures so that no pockets are left in which fluid can accumulate
• Do not suture the incision closed

Question 12

Green LO How do you orient the sutures for aural hematoma repair?

Answer 12

• Vertical mattress

- Don’t want to ligate the arteries

Question 13

Green LO How do you suture the incision through which the hematoma was removed?

Answer 13

• You don’t

Question 14

Describe the bandage for aural hematomas

Answer 14

You basically do little stirrups on either side and then tape it around the head

• Make sure you label where the ear is though

Question 15

Clicker Question

Which of the following is NOT a goal of surgery for aural hematoma?

Answer 15

1. Remove hematoma
2. Prevent recurrence
3. Minimize surgical scar formation
4. Retain ear appearance

Question 16

Diagnostic tests for otitis externa

Answer 16

• Otoscopic exam (min*)
• Cytologic exam (min*)
• Culture and sensitivity
• Systemic evaluation
• Radiograph or CT
• Cranial nerve function (document preop)
• Hearing loss (document preop)

Question 17

What are the three surgical options for end-stage otitis externa?

Answer 17

• Total ear canal ablation with lateral bulla osteotomy
• Lateral canal resection (Zepp-Lacroix)
• Vertical ear canal ablation

Question 18

Why is a bulla osteotomy required if you take out the ear canal?

Answer 18

• Drainage
• Lining of the bulla produces a sebaceous material
• If you leave the lining in the middle ear, the sebaceous material will build up

Question 19

Black LO Which surgery is always performed in conjunction with TECA?

Answer 19

• Lateral bulla osteotomy

Question 20

Black LO List 7 indications for total ear canal ablation.

Answer 20

1. Failed APPROPRIATE medical management
2. Severe proliferative disease affecting the ear canal
3. Concurrent otitis media
4. Proliferative to calcifying disease involving the horizontal ear canal
5. Failed lateral ear canal resection
6. Neoplasia of the ear canal
7. Severely stenotic canals?

Question 21

Black LO Which are complications associated with TECA?

Answer 21

• Hemorrhage
• Wound infection/dehiscence
• Facial nerve paralysis
• Horner’s syndrome
• Inner ear damage and vestibular dysfunction
• Fistula or abscess formation
• Effect on hearing from bone conduction