829
edits
Changes
no edit summary
==Description==
==Description==
An oesophageal diverticulum is a circumscribed sacculation of the wall of the oesophagus. The diverticulum may be '''congenital''' or '''acquired''' and congenital diverticula usually occur due to a defect in the muscle layers of the oesophagus through which the mucosa can herniate. Acquired diverticula can be divided into:
*'''Traction diverticula''' involve all of the layers of the oesophageal wall and occur when '''peri-oesophageal inflammation and fibrosis''' result in the formation of adhesions between the oesopagus and surrounding tissues, distorting the normal contours of the oesophageal wall. They develop most commonly in the cranial and middle portions of the oesophagus.
*'''Pulsion diverticula''' are similar to congenital divericula in that the mucosa herniates through an acquired defect in the outer layers of the wall. They may be caused by any condition that places internal radial stress on the oesophageal wall, such as increases in intraluminal oesophageal pressure. '''[[Oesophageal Foreign Body|Foreign bodies]]''', '''[[Vascular Ring Anomaly|vascular ring anomalies]]''', '''[[Oesophageal Stricture|strictures]]''' and severe '''[[Oesophagitis|oesophagitis]]''' can all therefore lead to the development of pulsion diverticula.
==Typical Signalment==
==Signalment==
Diverticula are rare in small animals and occur with no apparent breed or sex predilections. They should not be confused with normal variants of oesophageal anatomy, as occur particularly in Chinese Shar-peis which may have extra oesophageal loops or folds.
==Diagnosis==
==Diagnosis==
===Clinical Signs===
===Clinical Signs===
Signs may be related to the underlying cause of the diverticulum or to the presence of impacted food or retained fluid in the sacculated area. Small diverticula may cause no clinical signs but otherwise, the following signs may occur:
*regurgitation
*'''Regurgitation''' with hypersalivation
*odynophagia
*'''Difficulty in swallowing''', manifesting as odynophagia (pain on swallowing), retching and repeated efforts to swallow.
*'''Post-prandial dyspnoea''' if the sacculation impinges on the lung fields.
*postprandial dyspnoea
*'''Aspiraton pneumonia''' with tachypnoea, dyspnoea, pyrexia and coughing may occur with any cause of chronic regurgitation.
*anorexia
*Signs that occur if the oesophagus ruptures are described [[Rupture of the Oesopahgus|here]].
*sepsis if the diverticulum becomes perforated
===Diagnostic Imaging===
===Diagnostic Imaging===
'''Survey radiography''': may show an air/soft tissue density next to or involving the oesophagus
'''Plain radiographs of the chest''' may show an area of air or soft tissue density in assoication with the oesophagus. This finiding is not definitive as it may represent a [[Oesophageal Neoplasia|peri-oesophageal mass]], a [[Hiatal Hernia|hiatal hernia]] or another lesion of the lungs or mediastinum.
'''Contrast radiography''': will show focal dilation or a partial or complete filling of contrast media in the lumen of the oesophagus.
Administration of a '''radio-opaque contrast medium''' (such as barium) should outline the extent of the dilation.
'''Endoscopy''' (oesophagoscopy) can be used to provide a definitive diagnosis by visualising the sacculation.
==Treatment==
==Treatment==
*'''Small diverticula''' - managed by feeding bland soft or liquid diets.
Any underlying cause of an acquired diverticulum should be removed or treated where possible. Diverticula themselves may be managed medically or surgically, depending on their size.
*'''Small pulsion diverticula''' - should be surgically corrected as food impaction may enlarge the diverticula.
*'''Small diverticula''' may be managed medically by feeding '''soft or liquid diets''' and '''elevating the forelimbs''' of the animal for 10-15 minutes after each meal to encourage food boluses to pass into the stomach.
*'''Larger diverticular''' and '''small pulsion diverticula''' should be corrected surgically as they are more likely to cause clinical signs and because pulsion diverticula may enlarge over time as food becomes impacted in the sacculation. A '''diverticulectomy''' is performed after entering the chest cavity by a lateral thoracostomy or median sternotomy, depending on its exact location. The diverticulum is removed and the wall of the oesophagus is sutured longitudinally to try to prevent the formation of strictures. Since the oesophagus has no serosal layer, the repair may be augmented with muscle flaps (from the longus colli or intercostal muscles), with omentum brought into the chest cavity or with synthetic mesh. It is important that the repair not be under tension to prevent dehiscence and a headcollar and side reins may be used post-operatively to prevent this.
==Prognosis==
==Prognosis==
The prognosis is fair to guarded due to possible post-operative complications of oesophageal hypomotility and [[Oesopahgeal Stricture|oesophageal stricture]] formation.
==References==
==References==
Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) '''BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition)''' ''BSAVA''
Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) '''BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition)''' ''BSAVA''
Merck & Co (2008) '''The Merck Veterinary Manual'''
Ettinger, S.J, Feldman, E.C. (2005) '''Textbook of Veterinary Internal Medicine''' (6th edition, volume 2)
[[Category:Oesophagus_-_Pathology]]
[[Category:Oesophagus_-_Pathology]]
[[Category:To_Do_-_James]]
[[Category:To_Do_-_James]]
[[Category:Dog]][[Category:Cat]]
[[Category:Dog]][[Category:Cat]]