Esophagus

Question 1

Esophagus

Answer 1

Functional sphincter at both ends
Cranial= cricopharyngeal
caudal= gastroesophageal
Lies dorsal to trachea- thus enlargement causes ventral displacement of trachea
Normally not visible on radiograph
Occasionally small amount of gas or fluid- usually not significant

Question 2

Tracheoesphageal stripe sign

Answer 2

summation opacity of the tracheal and esophageal wall

Question 3

Esophagram

Answer 3

Used for assessing esophageal function and structure
assessing function requires dynamic evaluation- fluoroscopy
Easy to assess structure

Question 4

Esophagram- indications

Answer 4

Regurgitation (vs vomiting)- dynamic assessment preferred
Dysphagia- dynamic assessment preferred
Survey radiographic findings- static esophagram may help

Question 5

Swallowing disorders

Answer 5

Cricopharyngeal dysfunction- failure of sphincter to relax, poor timing of pharynx contraction vs sphincter relaxation (asynchrony)
Unable to propel food from pharynx into esophagus
need dynamic study to diagnose

Question 6

Esophageal dysfunction

Answer 6

May lead to dilation (megaesophagus)

Question 7

Esophageal dysfunction- segmental

Answer 7

congenital- vascular ring anomaly
acquired- stricture, foreign body, geriatric onset lyrngeal polyneuopathy
Always check for aspiration pneumonia

Question 8

Esophageal dysfunction- generalized

Answer 8

Congenital- idiopathic neuromuscular dysfunction
Acquired- aerophagis (cats), esophagitis, esophago-gastric obstruction, neuromuscular dysfunction (idiopathic, m gravis- thymoma)

Question 9

Generalized megaesophagus

Answer 9

Tubular structure in lateral view
Dorsal to trachea and caudal vena cava
trachea displaced ventrally
Usually gas filled but may contain fluid/ingesta
Converging funnel opacity in caudal thorax in VD- as it approaches diaphragm

Question 10

Segmental megaesophagus

Answer 10

Focal mass effect or gas accumulation
Trachea usually displaced ventrally if abnormality is cranial to heart base
Midline opacity on VD view
Hard to see because of lots of superposition

Question 11

Vascular ring anomalies

Answer 11

More common in dogs than cats
Arise from aortic arch or subclavian artery abnormalities
esophagus dilated cranial to heart base
Many patients also have generalized idiopathic neuromuscular dysfunction which negatively impacts prognosis

Question 12

PRAA

Answer 12

focal left displacement of trachea

Question 13

Preferred locations for esophageal foreign bodies

Answer 13

where there is narrowing or some resistance