Difference between revisions of "Category:Oesophagus - Pathology"

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====[[Squamous Cell Carcinoma]] of Other Species====
 
====[[Squamous Cell Carcinoma]] of Other Species====
*Squamous cell carcinomas of the [[Oesophagus - Anatomy & Physiology|oesophagus]] are occasionally seen in other species, notably in the cat, where the tumour tends to infiltrate around the oesophageal wall resulting in a “'''ring carcinoma'''”.
 
*The affected cat has progressive difficulty in eating and [[Deglutition|swallowing]].
 
*Forms part of [[Upper Alimentary Tract Carcinoma Complex]]
 
  
 
==Traumatic Pathology==
 
==Traumatic Pathology==

Revision as of 11:32, 28 May 2010



Introduction

  • The oesophagus is the part of alimentary tract that tends to go wrong least often.


  • Failure of oesophageal function results in obstruction and in failure of ingesta to pass to the stomach.
  • In the bovine there may also be failure of eructation and tympany may develop.

Defence Mechanisms

  • The oesophagus has no serosa and is covered by the fibrous tissue of the neck and mediastinum, from which it derives its blood supply.
  • Consequently, infection spreads easily and healing is more difficult.
  • Oesophageal disease is therefore difficult to treat and is consequently very serious.



Upper Alimentary Tract Carcinoma Complex

Squamous Cell Carcinoma of Other Species

Traumatic Pathology

Impaction

Upper Block Lower Block
Acute vomiting Gradual intestinal distention
Dehydration Mucosal destruction
Alkalosis Toxaemia
Pre-renal azotaemia Peritonitis


  • Commonly in cattle, horses and dogs.
  • The most common sites of obstruction are the thoracic inlet, the base of the heart, and the hiatus oesophagus of the diaphragm, i.e.: the narrowest points.

Clinical Signs

Horse

  • With foods that expand in oesophagus such as haylage etc.
  • Also seen with whole apples.

Cattle

Impaction of a bovine oesophagus (Courtesy of Alun Williams (RVC))
  • May eat a spherical object that obstructs the oesophagus mostly in anterior 1/3rd of oesophagus and can often be palpated in live animal.
  • Potatoes can be a cheap source of feed and if fed whole can become stuck in oesophagus.
  • If obstruction occurs further down can be difficult to diagnose and remove.
  • Cattle develop bloat when oesophagus obstructed.
  • Apples fairly easily to dislodge.

Dog

  • Usually with small bones
  • Animals that feel protective of feed may gulp food down quickly, particularly if given small chops / knuckle bones.
  • Knobbly shape may make bone lodge in oesophagus, particularly just anterior to heart.
  • Very difficult to dislodge (because of shape).
  • Pressure necrosis occurs very quickly around it and can erode through oesophagus within about 24 hours.
  • Small bone may also lodge in duodenum if they pass through the stomach.

Rupture

  • Perforation may occur with sharp foreign bodies. This may lead to cellulitis or pleurisy and other complications.
  • Rupture of the oesophagus admits pathogenic organisms to the mediastinum and fascial planes of the neck. Both are composed of loose connective tissue and communicate with each other.
  • Infection spreads rapidly as a cellulitis, aided possibly by peristalsis and pulsation of the carotid arteries, and soon leads to pleurisy.
  • Rupture is almost always fatal.


Learning Tools

Oesophagus Flashcards