Guttural Pouch Disease Flashcards
What is a GP?
Diverticula of Eustachian tube
What species have GP?
Horses
How much fluid can a GP hold?
300-500mls
GP communicates with what other structure and through what orifice?
Pharynx, pharyngeal orifice
What are the divisions of the GP? Which is the largest division?
Later and medial pouches, medial pouch is larger
What vascular structures are in the GP?
Internal carotid
External carotid
Maxillary artery
What neural structures are in the GP?
Sympathetic trunk
CN - VI, IX, X, XI, XII
GP tympany is seen in what age group?
Foals
What is GP tympany?
Non-painful distention of the GP with air
Is GP tympany unilateral or bilateral?
Can be either
What is most noticeable clinical sign of GP tympany? What other CS can you see?
Soft, non-painful external swelling of the throat-latch region in a foal.
Other - respiratory stertor, resp difficulty, dysphagia (+/- asp pneumonia)
Cause of GP tympany?
Unknown, thought to be congenital. Possible abnormal or excessive mucosal flap at pharyngeal orifice acting as a one way valve.
Diagnosis of GP tympany?
Signalment, clinical signs, air-filled GP on rads
Treatment of GP tympany?
Surgery usually necessary. If unilateral - fenestartion between the two GPs. If bilateral - resection or modification of pharyngeal orifice.
Prognosis of GP tympany (complicated and uncomplicated)?
Good if uncomplicated
Poor to guarded if dysphagia or asp pneumonia
What is GP empyema?
Purulent exudate in the GP
What organisms can cause GP empyema?
Strep equi or zooepidemicus
What causes GP empyema?
Usually secondary to a URI
Can be cause by rupture of a local lymph node
Clinical signs of GP empyema
Nasal discharge
Regional LN enlargement
Dysphagia (less common)
Chronic GP empyema can cause a firm mass called what?
Chondroid
Diagnosis of GP empyema
History of URI
Physical exam
CS
Confirmed with endoscopy and rads
Treatment of GP empyema
Aggressive lavage
Local and systemic abx
Surgical lavage and drainage my be needed if severe (chondroids present)
Prognosis of GP empyema?
Good to excellent
What is GP mycosis
Development of fungal plaques in the GP
Where in the GP do fungal plaques form?
Dorsal aspect of the GP
Common pathogen in GP mycosis?
Aspergillosis
Why do epistaxis and dysphagia occur with GP mycosis?
Erosion of arteries/nerves by the fungal plaque
Clinical signs of GP mycosis
Hemorrhage/epistaxis if an artery is involved - can be fatal
Dysphagia, horners, facial nerve paralysis if neural structures involved
Diagnosis of GP mycosis
Clinical signs
Endoscopy
When would you not continue with endoscopy if you suspect GP mycosis?
If a hemorrhage or blood clot is present at the pharyngeal orifice. This could result in disruption of the clot and more hemorrhage.
Treatment of GP mycosis
Can resolve spontaneously.
If epistaxis or dysphagia observed, you should intervene.
Surgical occlusion of affected arteries, even if only neuro signs are present.
You can give antifungals, just less efficacious.
Prognosis of GP mycosis
Guarded to fair.
Dysphagia worsens prognosis, takes time for neural structures to heal.
