4,503
edits
Changes
Equine Lower Respiratory Tract - Horse Anatomy (view source)
Revision as of 21:14, 18 November 2012
, 21:14, 18 November 2012no edit summary
==Pleural Cavity and Membranes==
==Pleural Cavity and Membranes==
Two pleural sacs line thoracic cavity, contacting in the medial plane to form the mediastinum. The pleura that covers the diaphragm ('''diaphragmatic pleura''') reflects on itself to become the '''costal pleura''' that lines the ribs, this '''line of pleural reflection''' follows the attachment of the diaphragm. Craniodorsal to the line of pleural reflection the diaphragmatic and costal pleura are in contact, separated by potential space known as the '''costodiaphragmatic recess'''.
==Mediastinum==
==Mediastinum==
The mediastinum contains the heart and all other thoracic organs (heart, oesophagus, trachea, aorta, thymus) except the lungs (which are within the pleural sacs) and the caudal vena cava. In regions where the mediastinum contains no organs, it is thin and may be fenestrated. Fenestrations are mainly caudal to the heart. This part of the mediastinum is pushed to the left due to the mass of the larger right lung.
==Diaphragm==
==Diaphragm==
The diaphragm is a musculotendinous structure that separates the thoracic and abdominal cavities. Ii inserts on the thoracic wall in a curve from the 8th and 9th costal cartilages, across costochondral junctions of the 9th-15th ribs to the middle of the 18th rib; where it turns craniomedially to end at vertebral end of the last rib. The dome of the diaphragm bulges forward to 7th-8th intercostal space, thus is almost opposite the olecranon in the standing horse.
There are three openings in the diaphragm as follows:
*Aortic hiatus: Between the right and left crura, dorsal diaphragm. The aorta passes through this opening.
*Oesophageal hiatus: Located in the right crus, the oesophagus passes through here.
*Caval foramen: Located in the muscular centre of the diaphragm, the caudal vena cava passes through here.
[[Category:Horse Anatomy]]
[[Category:Horse Anatomy]]
[[Category:To Do - AP Review]]