33a: Guttural Pouch Disease

What are guttural pouches

Paired extensions of the eustachian tubes

What divides the guttural pouches into medial and lateral compartments

Stylohyoid bones

Important structures that run along the caudal wall of the medial compartment of the guttural pouches

• CN 9-12

• Sympathetic trunk

• Internal carotid artery

Important structures that run along the walls of the lateral compartment of the guttural pouches

• External carotid artery

• Maxillary artery

• Mandibular nerve

• Facial nerve

Where are the openings to the guttural pouches

Dorsolateral pharynx

Surgical approaches to the guttural pouches

• Modified whitehouse

• Viborg’s approach

• Hyovertebrotomy

Guttural pouch tympany

Pouches filled with air

General cause of guttural pouch tympany

Functional abnormality of the normal anatomy where the pouches are acting as a one-way valve

Possible causes of guttural pouch tympany

• Dysfunction of pharyngeal openings

• Upper airway inflammation or infection

• Persistent cough

• Muscular dysfunction

Demographic for guttural pouch tympany

Young Arabian fillies

T/F: guttural pouch tympany is typically bilateral

False

CS of guttural pouch tympany

• Gurgling during nursing

• Bullfrog swelling of throat region

• Dysphagia

• Aspiration

• Dyspnea if bilateral

• Secondary infection

Diagnosis for guttural pouch tympany

• CS

• Endoscopy

• Rads

Endoscopy findings consistent with guttural pouch tympany

• Collapse of dorsal nasopharynx

• Pouch deflates when you insert the endoscope

• Normal anatomy

Treatment for guttural pouch tympany

• Relieve respiratory obstruction and dysphagia

• Enlarge pharyngeal openings

• Create communication with normal pouch through the septum

Conservative treatment for guttural pouch tympany

Leave a foley catheter in the pharyngeal flap for 4-6 weeks to induce remodeling of wider opening

Surgical treatment for guttural pouch tympany

• Septum fenestration

• Salpingopharyngeal fistula (useful for bilateral disease)

Guttural pouch empyema

Purulent material within the guttural pouches

What happens if guttural pouch empyema becomes chronic

Turns into chondroids

Primary cause of guttural pouch empyema

Sequela of URT infection or retropharyngeal LN abscess rupture

CS of guttural pouch empyema

• Intermittent nasal discharge

• Swollen LNs

• Dysphagia

• Respiratory noise

• Distension of guttural pouch

Disease frequently associated with guttural pouch empyema

Strangles

Diagnostics for guttural pouch empyema

• Endoscopy

• Rads

• Culture

• PCR

Treatment for guttural pouch empyema

• Daily saline lavage for multiple days

• NSAIDs

• Severe: systemic antibiotics

Treatment for guttural pouch chondroids

• Break up with endoscope and remove

• Surgical removal

T/F: we can use local agents to dissolve guttural pouch chondroids

FALSE (except maybe acetylcysteine)

Where do we usually see guttural pouch mycosis

Along the roof of one pouch

Primary agent causing guttural pouch mycosis

Aspergillus

CS of guttural pouch mycosis

• Epistaxis

• Dysphagia

• Abnormal respiratory noise

• Horner’s syndrome

Why is guttural pouch mycosis potentially fatal

Fungal plaques can erode into the internal or external carotid arteries, which will kill them in short order

Cause of dysphagia associated with guttural pouch mycosis

Damage to pharyngeal branches of the vagus and glossopharyngeal nerves

Diagnosis for guttural pouch mycosis

Endoscopy

Treatment for non-emergency guttural pouch mycosis

• Topical ± systemic antifungals

• Lavage

• Careful removal of plaques

When is it appropriate to remove fungal plaques from guttural pouch mycosis

If it is not on the artery, or if you occlude the artery beforehand

Treatment for emergency presentations of guttural pouch mycosis

• Surgical ligation

• Balloon catheter occlusion

Proposed cause of temporohyoid osteoarthropathy

Extension from inner/middle ear infection or DJD

Pathophysiology of THP

Temporohyoid joint fuses → tongue or larynx movement causes fracture of the petrous part of the temporal bone → nerve deficits

CS of THO

• Early: reluctance to take the bit, head tossing, pain around hear

• Later: acute CN VII and VIII deficits

Diagnostics for THO

• CT

• Endoscopy

• Rads

Treatment for THO

• Medical: NSAIDs and antibiotics

• Surgical: partial ceratohyoidectomy, ceratohyoidectomy, or partial stylohyoidectomy