|
Posterior Auricular Artery
The posterior auricular artery is a small artery that arises from the external carotid artery. It ascends along the side of the head. It supplies several muscles of the neck and several structures of the head. Structure Origin The artery arises from (the posterior aspect of) the external carotid artery. Its origin occurs immediately superior to the digastric muscle and stylohyoid muscle, and opposite the apex of the styloid process. Course The artery passes superior-ward in beneath the parotid gland and styloid process of temporal bone The temporal bone is a paired bone situated at the sides and base of the skull, lateral to the temporal lobe of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples where four of the cranial bone .... Next, it courses along a groove between the cartilage of the auricle and the mastoid process. It then divides into its terminal auricular and occipital branches. Branches and distribu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Carotid Artery
The external carotid artery is the major artery of the head and upper neck. It arises from the common carotid artery. It terminates by splitting into the superficial temporal and maxillary artery within the parotid gland. Structure Origin The external carotid artery arises from the common carotid artery just inferior to the upper border of the thyroid cartilage. At its origin, this artery is closer to the skin and more medial than the internal carotid, and is situated within the carotid triangle. Course and fate It curves to pass anterosuperiorly before inclining posterior-ward to reach the space posterior the neck of the mandible, where it divides into the superficial temporal and maxillary artery within the parotid gland. It rapidly diminishes in size as it travels up the neck, owing to the number and large size of its branches. Relations At the origin, external carotid artery is more medial than internal carotid artery. When external carotid artery ascends the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastoid Process
The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, the mastoid part articulates with two other bones. Etymology The word "mastoid" is derived from the Greek word for "breast", a reference to the shape of this bone. Surfaces Outer surface Its outer surface is rough and gives attachment to the occipitalis and posterior auricular muscles. It is perforated by numerous foramina (holes); for example, the mastoid foramen is situated near the posterior border and transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater. The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital. Mastoid process The mastoid process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Auricular Branches Of Superficial Temporal Artery
The anterior auricular branches of the superficial temporal artery are distributed to the anterior portion of the auricula, the lobule, and part of the external meatus, anastomosing with the posterior auricular. They supply the external acoustic meatus The ear canal (external acoustic meatus, external auditory meatus, EAM) is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the auricle to the eardrum and is about in length and in diameter. Str ... and the visible part of the ear. Arterial vascular pattern of the auricle: "The superior and the inferior anterior auricular artery provided the vascular supply to the helical rim, forming an arcade, i.e. helical rim arcade. On the superior third of the helical rim another arcade was confirmed between the superior anterior auricular artery and the posterior auricular artery (PAA), i.e. the helical arcade. The perforators of the PAA were identified lying in a vertical line 1 cm post ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semicircular Canals
The semicircular canals are three semicircular interconnected tubes located in the innermost part of each ear, the inner ear. The three canals are the lateral, anterior and posterior semicircular canals. They are the part of the bony labyrinth, a periosteum-lined cavity on the petrous part of the temporal bone filled with perilymph. Each semicircular canal contains its respective semicircular duct, i.e. the lateral, anterior and posterior semicircular ducts, which provide the sensation of angular acceleration and are part of the membranous labyrinth—therefore filled with endolymph. Structure The semicircular canals are a component of the bony labyrinth that are at right angles from each other and contain their respective semicircular duct. At one end of each of the semicircular ducts is a dilated sac called a membranous ampulla, which is more than twice the diameter of the ducts. Each ampulla contains an ampullary crest, the crista ampullaris which consists of a t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastoid Antrum
The mastoid antrum (tympanic antrum, antrum mastoideum, Valsalva's antrum) is an air space in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells and anteriorly with the epitympanic recess of the middle ear via the aditus to mastoid antrum (entrance to the mastoid antrum). These air spaces function as sound receptors, provide voice resonance, act as acoustic insulation and dissipation, provide protection from physical damage and reduce the mass of the cranium. The roof is formed by the tegmen antri which is a continuation of the tegmen tympani and separates it from the middle cranial fossa. The lateral wall of the antrum is formed by a plate of bone which is an average of 1.5 cm in adults. The mastoid air cell system is a major contributor to middle ear inflammatory diseases. Additional images File:Gray1209.png, Left temporal bone showing surface markings for the tympanic antrum (red), transverse sinus (blue), and facial nerve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastoid Cells
The mastoid cells (also called air cells of Lenoir or mastoid cells of Lenoir) are air-filled cavities within the mastoid process of the temporal bone of the cranium. The mastoid cells are a form of skeletal pneumaticity. Infection in these cells is called mastoiditis. The term ''cells'' here refers to enclosed spaces, not cells as living, biological units. Anatomy The mastoid air cells vary greatly in number, shape, and size; they may be extensive or minimal or even absent. The cells are typically interconnected and their walls lined by mucosa that is continuous with that of the mastoid antrum and tympanic cavity. Extent They may excavate the mastoid process to its tip, and be separated from the posterior cranial fossa and sigmoid sinus by a mere slip of bone or not at all. They may extend into the squamous part of temporal bone, petrous part of the temporal bone zygomatic process of temporal bone, and - rarely - the jugular process of occipital bone; they may thus c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facial Nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerve typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI (abducens nerve) and anterior to cranial nerve VIII (vestibulocochlear nerve). The facial nerve also supplies preganglionic parasympathetic fibers to several head and neck ganglia. The facial and intermediate nerves can be collectively referred to as the nervus intermediofacialis. The path of the facial nerve can be divided into six segments: # intracranial (cisternal) segment (from brainstem pons to internal auditory canal) # meatal (canalicular) segment (with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylomastoid Foramen
The stylomastoid foramen is a foramen between the styloid and mastoid processes of the temporal bone of the skull. It is the termination of the facial canal, and transmits the facial nerve, and stylomastoid artery. Facial nerve inflammation in the stylomastoid foramen may cause Bell's palsy. Structure The stylomastoid foramen is between the styloid and mastoid processes of the temporal bone. The average distance between the opening of the stylomastoid foramen and the styloid process is around 0.7 mm or 0.8 mm in adults, but may decrease to around 0.2 mm during aging. The stylomastoid foramen transmits the facial nerve, and the stylomastoid artery. These 2 structures lie directly next to each other. Clinical significance Bell's palsy can result from inflammation of the facial nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylomastoid Artery
The stylomastoid artery enters the stylomastoid foramen and supplies the tympanic cavity, the tympanic antrum and mastoid cells, and the semicircular canals. It is a branch of the posterior auricular artery, and thus part of the external carotid arterial system. In the young subject, a branch from this vessel forms, with the anterior tympanic artery from the internal maxillary, a vascular circle, which surrounds the tympanic membrane, and from which delicate vessels ramify on that membrane. It anastomoses with the superficial petrosal branch of the middle meningeal artery The middle meningeal artery (') is typically the third branch of the maxillary artery#First portion, first portion of the maxillary artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum t ... by a twig which enters the hiatus canalis facialis. References External links ArcLab Arteries of the head and neck {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Bone
The temporal bone is a paired bone situated at the sides and base of the skull, lateral to the temporal lobe of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples where four of the cranial bones fuse. Each temple is covered by a temporal muscle. The temporal bones house the structures of the ears. The lower seven cranial nerves and the major vessels to and from the brain traverse the temporal bone. Structure The temporal bone consists of four parts—the squamous, mastoid, petrous and tympanic parts. The squamous part is the largest and most superiorly positioned relative to the rest of the bone. The zygomatic process is a long, arched process projecting from the lower region of the squamous part and it articulates with the zygomatic bone. Posteroinferior to the squamous is the mastoid part. Fused with the squamous and mastoid parts and between the sphenoid and occipital bones lies the petrous part, which is shaped li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Auricular Vein
The posterior auricular vein is a vein of the head. It begins from a plexus with the occipital vein and the superficial temporal vein, descends behind the auricle, and drains into the external jugular vein. Structure The posterior auricular vein begins upon the side of the head, in a plexus which communicates with the tributaries of the occipital vein and the superficial temporal vein. It descends behind the auricle. It joins the posterior division of the retromandibular vein. It drains into the external jugular vein. It receive the stylomastoid vein, and some tributaries from the cranial surface of the auricle. Variation The posterior auricular vein may drain into the internal jugular vein The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve. It begins in the posteri ... or a posterior jugular v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parotid Gland
The parotid gland is a major salivary gland in many animals. In humans, the two parotid glands are present on either side of the mouth and in front of both ears. They are the largest of the salivary glands. Each parotid is wrapped around the mandibular ramus, and secretes serous saliva through the parotid duct into the mouth, to facilitate mastication and swallowing and to begin the digestion of starches. There are also two other types of salivary glands; they are submandibular and sublingual glands. Sometimes accessory parotid glands are found close to the main parotid glands. The venom glands of snakes are a modification of the parotid salivary glands. Etymology The word ''parotid'' literally means "beside the ear". From Greek παρωτίς (stem παρωτιδ-) : (gland) behind the ear < παρά - pará : in front, and οὖς - ous (stem ὠτ-, ōt-) : ear. Structure The parotid glands are a pair of mainly[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
