Branches of the External Carotid Artery of the Dromedary, Camelus Dromedarius Artery Origin Course Distribution
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Table 3.4: Branches of the External Carotid Artery of the Dromedary, Camelus dromedarius Artery Origin Course Distribution Originates at the bifurcatio of the occipital artery from the common carotid artery. Superficial Occipital region, lateral face, pharynx, Common Carotid External Carotid course is throughout occipital and posteroinferior tongue, hyoid musculature, and Artery facial regions; deeper course is throughout sublingual glands. pharyngeal, lingual, and hyoid regions. The proper occipital artery is the first dorsal branch of the ECA. It arises near the caudal border of the wing of the atlas, traverses the atlantal fossa, and then splits into: 1. Multitude External Carotid of muscular branches; 2. Anastomosis with Collateral circulation with vertebral Occipital Artery vertebral artery (through alar foramen); 3. arteries; neck and occipital muscles Superior termination continues to course toward the external occipital protuberance, supplying the parenchyma of the occipital region inferior to and surrounding the foramen magnum. Variable origin: from the ECA or the "ascending pharyngeal." Condylar and ascending pharyngeal External Carotid may share a short common trunk. An anterior Artery (var: branch of the condylar artery follows the Inferior meninges and inferolateral Condylar Ascending hypoglossal nerve into the hypoglossal canal to occipital region. Pharyngeal) supply the inferior meninges. A posterior branch of the condylar provides collateral circulation to the occipital region. External Carotid Small, tortuous division from medial wall of Cranial Thyroid Thyroid Artery ECA From posteromedial surface of ECA Descending External Carotid immediately posterior to the jugular process. Extensive distribution throughout the Pharyngeal Artery Convoluted and highly dendritic throughout the pharynx lateral and posterior wall of the pharynx. Artery Origin Course Distribution Nearly all oxygenated blood to the ear The common auricular departs the superior wall is supplied through this singular, large of the ECA near the jugular process and follows parent artery. At its dorsal termination, External Carotid the temporal crest toward the auricle. Near the Caudal Auricular the common auricular divides into no Artery external acoustic meatus, the common auricular fewer than 7 branches that distribute gives off the ramus occipitalis. It is highly to the circumference of the auricular dendritic near tis superior termination. base The occiputal ramus of the common auricular artery breaks away from the parent artery approximately posterior to the external acoustic meatus. While the common auricular traverses the rostral/dorsal surface of the mastoid and nuchal crest, the ramus occipitalis scours the posterior/caudal surface of the same bones, leaving an oblique impression on the mastoid Occipital region superior to the Ramus Occipitalis Common auricular and a consistent groove on the inferior surface of foramen magnum; caudal meninges the nuchal crest. The ramus occipitalis sends several branches into the muscle, connective tissue, and skin of the superior occipital region, and then terminates by entering the large mastoid foramen. Upon entering the braincase, the artery continues as the caudal meningeal artery. Before entering the mastoid foramen, the ramus receives collateral input from the caudal deep temporal. From deep surface of the common auricular a., immediately distal to the departure of the Stylomastoid Common auricular occipital ramus. Virtually indetectable Middle ear and tympanum extracranial course; enters stylomastoid foramen, traverses facial canal to supply middle ear. Intracranial continuation of the ramus occipitalis Caudal Meningeal Ramus occipitalis Caudal portion of the meninges artery Artery Origin Course Distribution Common trunk for facial and common auricular = first major dorsal branch of the ECA; the facial departs laterally near the condylar process of the mandible / temporomandibular joint. Proceeds rostroventrally along the posterior border of the mandibular ramus. At the Parotid gland (minimal), masseter, mandibular angle, the facial artery curves parenchyma of face, muscles of facial External Carotid anteriorly, coursing superficial to the masseter expression below the zygomaticus, Facial Artery / Common muscle. Across this muscle, the facial artery lateral nasal region, lower lip, and to a auricular contributes a number of small branches to lesser extent, the upper lip. Note that perfuse the muscle and its fibrous sheath. At the upper lip receives most of its blood approximately the third lower muscle, the facial supply from the infraorbital artery artery splits into dorsal and ventral rami. The smaller dorsal ramus anastomoses with the transverse facial and infraorbital/lateral nasal arteries. The larger ventral ramus continues anteriorly toward the lower lip. No single, discrete vessel supplies the upper lip. Inferolateral fleshy nasal vestibule; Anastomosis between A large anastomotic network from the lateral mucosa, epithelium, and muscles of Maxillary Labial dorsal rami facialis nasal region (largely consisting of the dorsal the upper lip.; rami to angularis oculi and infraorbital artery rami facialis and the infraorbital artery) supply and angularis oris m.'s the lip with a variable number of branches. Blood supply to the lower lip is more discrete Ventral Ramus Also ramified by the mental/inferior Mandibular Labial than that of the upper lip; the rostral termination Facialis alveolar artery of the facial artery Distributes across angle of the mouth, Ventral Ramus Dorsal branch from the ventral branch of the Angular anastomoses with dorsal rami facialis, Facialis facial artery infraorbital Artery Origin Course Distribution Common trunk with transverse facial artery has a 2.5 cm recurving course around mandible; within mandibular incisure (between condylar and angular processes) before bifurcating. Dorsal Zygomaticus, skin and muscle of External Carotid branch = superficial temporal; rostral Superficial Temporal temporal region, and posterior TMJ Artery continuation = transverse facial. The STA is capsule. relatively small and has a short course over the zygomaticotemporal junction before perfusing the inferolateral quadrant of the temporalis m. Sends small branches to the TMJ The transverse facial artery shares a common origin with the superficial temporal artery. The transverse facial is the larger caliber vessel. After the STA departs, the transverse facial External Carotid Muscles of mastication; superficial Transverse Facial continues rostrally. Close to the origin of the Artery structures overlying. TFA proper, 3 large branches depart the artery, radiating between 90 degrees ventrally to 20 degrees below the TFA. These distribute to the lateral muscles of mastication. Immediately posterior to the jugular process, the lingual artery branches from the ECA. It courses External Carotid Lingual along the ventral border of the hyoid apparatus Tongue and floor of oral cavity Artery before splitting into a deep lingual artery and a sublingual artery Lateral terminal branch of the lingual artery; Sublingual Lingual follows internal border of mandible, supplying Sublingual gland the sublingual gland Tortuous, profusely branching Deep Lingual Lingual Continuation of the lingual artery distribution within the intrinsic tongue musculature .