Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Y3 MOD Dentistry > Disease of the equine head and neck 4 > Flashcards

Disease of the equine head and neck 4 Flashcards

1
Q

What are the guttural pouches?

A

Air-filled, mucosa lined outpouchings of the auditory tubes connecting the nasopharynx to the middle ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the possible function of the guttural pouches?

A

Possibly related to cooling of the blood before reaching the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the features and bordering structures of the guttural pouches

A
  • Paired: median septum (very thin)
  • Approximately 350ml in volume
  • Dorsally: base of skull & 1st cervical vertebra. Tympanic bulla & auditory meatus
  • Medially: median septum, rectus capitus & longus capitis ventralis
    muscles
  • Ventrally: Retropharyngeal lymph nodes. Nasopharynx
  • Laterally: Parotid & mandibular salivary glands, Pterygoid muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does each pouch connect to the nasopharynx?

A
  • Via a funnel shaped
    auditory tube
  • Orifice has a fibrocartilage flap = The otium / ostia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which structure separates each guttural pouch into medial and lateral compartments?

A

Stylohyoid bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which arteries are associated with the guttural pouch?

A

Internal and external carotid arteries (ICA / ECA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the location and function of the Circle of Willis

A

Found at the base of the brain.
Ensures perfusion to the brain even if an artery is blocked – makes surgery to occlude the arteries in cases of guttural pouch mycosis more complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Each guttural pouch is composed of?

A

A medial and lateral compartment
MEDIAL > lateral
2/3 versus 1/3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Clinical signs of guttural pouch disease include?

A
  • Epistaxis
  • Dysphagia
  • Nasal discharge
  • Dyspnoea
  • External swelling
  • Neurological signs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the key points to note in the clinical assessment of a horse with suspected disease of the guttural pouch?

A
  • Epistaxis
  • Trauma
  • Nasal discharge
  • Recent Strep equi var equi infection?
  • Is emergency supportive
    treatment required first?
  • Respiratory distress (tracheostomy?)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is guttural pouch mycosis?

A

Fungal plague forms over artery

Most commonly the ICA but ECA / MA can occasionally be affected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the causative agent of guttural pouch mycosis?

A

Aspergillus spp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main signs/concerns with guttural pouch mycosis?

A
  • Relatively uncommon
  • EPISTAXIS
  • Potentially life threatening: fatal, uncontrolled haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Must rule out guttural pouch mycosis in horses with epistaxis particularly if there are which features?

A
  • Large volume of arterial haemorrhage from nares
  • History of recent epistaxis (may be fatal after 2 recent episodes)
  • No history of trauma / recent intense exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the history of a horse with guttural pouch mycosis?

A
  • Moderate to severe epistaxis
  • May have had several mild episodes in the previous days / weeks
    +/- dysphagia (lesions over nerves, can present without epistaxis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the main clinical signs of guttural pouch mycosis?

A 
Nasal discharge
Epistaxis
\+/- nerve dysfunction:
- Dysphagia
- Horners
- Laryngeal paralysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name the differential diagnosis for URT epistaxis?

A
  • Guttural pouch mycosis
  • Head trauma
  • Progressive ethmoid haematoma
  • Sinus trauma
  • Nasal passage trauma (iatrogenic)
  • Foreign body
  • Neoplasia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name the differential diagnosis for LRT epistaxis?

A
  • Exercise induced pulmonary haemorrhage
  • Neoplasia
  • Lower airway inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Name the cardiac differential diagnosis for epistaxis?

A
  • Atrial fibrillation

- Mitral insufficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is guttural pouch mycosis diagnosed?

A

Endoscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is seen when using endoscopy to diagnose guttural pouch mycosis?

A

Blood draining from ostium
- Usually unilateral but can be bilateral
• +/- DDSP or laryngeal paralysis
• +/- Pharyngeal collapse
• Diphtheritic membrane fungal plaque/blood clot overlying ICA/ECA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What care must be taken when using the endoscope in the case of a guttural pouch mycosis?

A

Care must be taken to avoid disrupting the clot and cause a fatal haemorrhage
Don’t enter GP with endoscope
Best to examine the guttural pouch at the surgical facility

23
Q

Describe the Initial triage & management on the yard in an emergency guttural pouch mycosis case

A

Do not wait to act!
GPM ASSOCIATED WITH EPISTAXIS IS A TRUE EMERGENCY
- Assess Cardiovascular status: HR / PP / MM colour / mentation
- Must keep the horse calm
- Minimise the risk of dislodging the clot & restarting haemorrhage
- Do not administer fluids / perform endoscopy within the guttural pouch on the yard
- Immediate transportation to a surgical facility
+/- administer Acepromazine as an anxiolytic if necessary

24
Q

Describe different surgical treatments for guttural pouch mycosis

A
  • Surgical occlusion of the affected artery/arteries: must occlude cardiac & cerebral side
  • Simple ligation of the ICA
  • Balloon catheterisation / Coil embolization, Nitrol plugs
  • Treat hypovolaemia: blood transfusion (during surgery)
25
Q

Describe when to use medical management of guttural pouch mycosis

A
  • Used following surgery to occlude the arteries

- Or in cases with NO arterial involvement (no history of bleeding, no plaques on/near arteries)

26
Q

How can guttural pouch mycosis be medically managed?

A
  • Topical/systemic antifungal tx = Enilconazole (‘Imaverol’)
    +/- laser fenestration
    Alter CO2 / O2 levels
27
Q

Rupture of which 2 muscles is a differential for blood emanating from the guttural pouch?

A

Rectus capitis

Longus capitis muscles

28
Q

How can rupture of the rectus capitis & longus capitis muscles occur?

A

When a horse rears or falls over (typically young horses being loaded / trained)

29
Q

What are the main differentials for dysphagia?

A
  • Oesophageal Obstruction
  • Retropharyngeal abscess
  • Other retropharyngeal masses e.g. neoplasia, haematoma
  • Guttural pouch mycosis
  • Guttural pouch empyema / inflammation
  • Equine Grass Sickness
  • Tetanus
  • Rabies
30
Q

What is the aetiological cause of Retropharyngeal abscess?

A

Streptococcus equi var equi

31
Q

Describe guttural pouch empyema

A

Purulent material in the guttural pouch

  • Liquid purulent material
  • Chondroids: inspissated purulent material
  • Secondary to URT infection / infusion of irritant drugs into the GP
32
Q

What are the clinical signs of guttural pouch empyema?

A

Purulent nasal discharge
+/- lymph node enlargement
+/- dyspnoea / dysphagia

33
Q

How is guttural pouch empyema diagnosed and what must always be ruled out during diagnosis?

A

Endoscopy
+/- radiography
- Always rule in / out Strep. equi var equi infection (strangles)

34
Q

What are chondroids and how do they develop?

A
  • Chronic infection results in inspissated purulent material developing
  • Development of chondroids results
  • Size / consistency / number variable
  • Removal more challenging due to their solid nature
35
Q

What must happen if a horse is +ve for Strep. equi var equi infection (strangles)?

A

Biosecurity & testing of others

36
Q

How is Empyema treated?

A

Endoscopic lavage

+/- indwelling catheters –can be challenging if they are soft but too firm to flush out

37
Q

How are chondroids treated?

A
  • Endoscopic assisted removal
  • Laser assisted techniques
  • Traditional direct surgical approaches
38
Q

Which animals are affected by guttural pouch tympany?

A

Foals - up to 1 year

39
Q

What is guttural pouch tympany?

A

Air trapped, one-way valve
Unilateral / bilateral
The guttural pouch becomes abnormally filled with air

40
Q

What are the clinical signs of guttural pouch tympany?

A

Marked retropharyngeal swelling
Respiratory stridor
Dysphagia

41
Q

How is guttural pouch tympany diagnosed?

A

Radiography - DV radiographs of the head useful to differentiate between uni or bilateral cases
Endoscopy

42
Q

How is guttural pouch tympany treated if it is unilateral vs bilateral?

A

If unilateral, allow air to escape via the
unaffected side
If bilateral, allow air to escape from both sides
• Placement of catheters until ongoing maturity results in functioning of ostium ostia and resolution of distention
• Surgery - fenestration of the median septum (if unilateral)
• Salpingopharyngeal fenestration - laser
(bilateral)

43
Q

Progressive disease of the middle ear / temporohyoid (TH) joint is termed?

A

Temporohyoid osteoarthropathy

44
Q

Describe the features and signs of Temporohyoid osteoarthropathy

A
  • Haematogenous infection of the joint and progression to thickening and fusion of the bone
  • Fracture of bone / damage to cranial nerves exiting the skull close to this site – NEUROLOGICAL SIGNS
  • Associated with some breeds (QH) and horses that crib-bite
45
Q

What are the 3 early clinical signs of Temporohyoid osteoarthropathy

A

Head shaking
Ear rubbing
Behavioural change

46
Q

Via what methods is Temporohyoid osteoarthropathy diagnosed?

A
  • Clinical signs
  • Endoscopy of the guttural pouches
  • Radiography
  • Computed tomography
  • Other neurological disease ruled out
47
Q

How is Temporohyoid osteoarthropathy initially managed?

A

Systemic antimicrobials
Systemic NSAIDs
Medical management of ocular signs

48
Q

What is otitis media?

A

Infection of the middle ear

49
Q

What are the features and clinical signs of otitis media?

A

Headshaking behaviour
Vestibular signs
+/- facial nerve signs
Infectious aetiology

50
Q

Which neoplasm is most common in a horses guttural pouch?

A

Melanoma

51
Q

Where is a tracheostomy tube placed?

A

midline, middle & upper thirds of the neck

52
Q

How the area for a tracheostomy tube

A
  • Clip the skin, initial sterile preparation
  • Inject 10ml of local anaesthetic
  • Aseptic preparation
  • Sterile gloves
53
Q

Describe placement of a tracheostomy tube

A
  • Vertical incision through the skin and sc tissues: stay on the midline
  • Make a horizontal incision between tracheal rings

Y3 MOD Dentistry (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions