| advertise add site services publishers database health videos | ![]() | about toolbar stats live show health store more stuff JOIN/LOGIN |
Ascending Aortic-Branch Access for Arch and Descending Thoracic Aortic ctsnet.org | Double aortic arches, esophageal atresia and tracheal compression Majid... jiaps.com |
The aortic arches are a series of six paired embryological vascular structures which give rise to several major arteries. They are ventral to the dorsal aorta.
[edit] Specific arches[edit] Arches 1 and 2The first and second arches disappear early, but the dorsal end of the second gives origin to the stapedial artery, a vessel which atrophies in humans but persists in some mammals. It passes through the ring of the stapes and divides into supraorbital, infraorbital, and mandibular branches which follow the three divisions of the trigeminal nerve. The infraorbital and mandibular arise from a common stem, the terminal part of which anastomoses with the external carotid. On the obliteration of the stapedial artery this anastomosis enlarges and forms the internal maxillary artery, and the branches of the stapedial artery are now branches of this vessel. The common stem of the infraorbital and mandibular branches passes between the two roots of the auriculotemporal nerve and becomes the middle meningeal artery; the original supraorbital branch of the stapedial is represented by the orbital twigs of the middle meningeal. [edit] Arch 3The third aortic arch constitutes the commencement of the internal carotid artery, and is therefore named the carotid arch. [edit] Arch 4The fourth right arch forms the right subclavian as far as the origin of its internal mammary branch; while the fourth left arch constitutes the arch of the aorta between the origin of the left carotid artery and the termination of the ductus arteriosus. [edit] Arch 5The fifth arch disappears on both sides. [edit] Arch 6The sixth right arch disappears; the sixth left arch gives off the pulmonary arteries and forms the ductus arteriosus; this duct remains pervious during the whole of fetal life, but then closes within the first few days after birth due to increased O2 concentration. Oxygen concentration causes the production of bradykinin which causes the ductus to constrict occluding all flow. Within 1-3 months, the ductus is obliterated and becomes the ligamentum arteriosus. His showed that in the early embryo the right and left arches each gives a branch to the lungs, but that later both pulmonary arteries take origin from the left arch. [edit] Additional images[edit] See also[edit] External links
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.
| ||||||||||||||||||||||||||||||||||||||||||||
| ↑ top of page ↑ | about thumbshots |