External Laryngeal Nerves
The superior laryngeal nerve is a branch of the vagus nerve. It arises from the middle of the inferior ganglion of vagus nerve and in its course receives a branch from the superior cervical ganglion of the sympathetic nervous system. The superior laryngeal nerve consists of two branches: the internal laryngeal nerve (sensory), which supplies sensory fibers to the laryngeal mucosa, and the external laryngeal nerve (motor), which innervates the cricothyroid muscle. The superior laryngeal nerve innervates the two cricothyroid muscles. The recurrent laryngeal nerve gets its name from the fact that it loops below the aorta on its way to the intrinsic muscles of the larynx. The left recurrent laryngeal nerve passes under and around the aorta on its way to the larynx, whereas the right recurrent laryngeal nerve passes under and around the subclavian artery. Because the aorta is inferior to the subclavian artery, the left recurrent laryngeal nerve is a bit longer than the right recurr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Glossopharyngeal Nerve
The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper Medulla oblongata, medulla, just anterior (closer to the nose) to the vagus nerve. Being a mixed nerve (sensorimotor), it carries afferent sensory and efferent motor information. The motor division of the glossopharyngeal nerve is derived from the Basal plate (neural tube), basal plate of the embryonic medulla oblongata, whereas the sensory division originates from the cranial neural crest. Structure From the anterior portion of the medulla oblongata, the glossopharyngeal nerve passes laterally across or below the Flocculus (cerebellar), flocculus, and leaves the skull through the central part of the jugular foramen. From the superior and inferior ganglia in jugular foramen, it has its own sheath of dura mater. The inferior ganglion on the inferior surface of petrous part of temporal is related with a tri ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Common Carotid Artery
In anatomy, the left and right common carotid arteries (carotids) ( in Merriam-Webster Online Dictionary '.) are that supply the head and neck with ; they divide in the neck to form the and [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Laryngopharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food and air to the esophagus and larynx respectively. The flap of cartilage called the epiglottis stops food from entering the larynx. In humans, the pharynx is part of the digestive system and the conducting zone of the respiratory system. (The conducting zone—which also includes the nostrils of the nose, the larynx, trachea, bronchi, and bronchioles—filters, warms and moistens air and conducts it into the lungs). The human pharynx is conventionally divided into three sections: the nasopharynx, oropharynx, and laryngopharynx. It is also important in vocalization. In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen. They are arranged as an i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Superior Thyroid Artery
The superior thyroid artery arises from the external carotid artery just below the level of the greater cornu of the hyoid bone and ends in the thyroid gland. Structure From its origin under the anterior border of the sternocleidomastoid the superior thyroid artery runs upward and forward for a short distance in the carotid triangle, where it is covered by the skin, platysma, and fascia; it then arches downward beneath the omohyoid, sternohyoid, and sternothyroid muscles. To its medial side are the inferior pharyngeal constrictor muscle and the external branch of the superior laryngeal nerve. Branches It distributes twigs to the adjacent muscles, and numerous branches to the thyroid gland, connecting with its fellow of the opposite side, and with the inferior thyroid arteries. The branches to the gland are generally two in number. One, the larger, supplies principally the anterior surface; on the isthmus of the gland it connects with the corresponding artery of the opposite ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Cricothyrotomy
A cricothyrotomy (also called cricothyroidotomy) is an incision made through the skin and cricothyroid membrane to establish a patent airway during certain life-threatening situations, such as airway obstruction by a foreign body, angioedema, or massive facial trauma. Cricothyrotomy is nearly always performed as a last resort in cases where other means of tracheal intubation are impossible or impractical. Compared with tracheotomy, cricothyrotomy is quicker and easier to perform, does not require manipulation of the cervical spine, and is associated with fewer complications. However, while cricothyrotomy may be life-saving in extreme circumstances, this technique is only intended to be a temporizing measure until a definitive airway can be established. Indications A cricothyrotomy is often used as an airway of last resort given the numerous other airway options available including standard tracheal intubation and rapid sequence induction which are the common means of establishing ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Thyroidectomy
A thyroidectomy is an operation that involves the surgical removal of all or part of the thyroid gland. In general surgery, endocrine or head and neck surgeons often perform a thyroidectomy when a patient has thyroid cancer or some other condition of the thyroid gland (such as hyperthyroidism) or goiter. Other indications for surgery include cosmetic (very enlarged thyroid), or symptomatic obstruction (causing difficulties in swallowing or breathing). Thyroidectomy is a common surgical procedure that has several potential complications or sequelae including: temporary or permanent change in voice, temporary or permanently low calcium, need for lifelong thyroid hormone replacement, bleeding, infection, and the remote possibility of airway obstruction due to bilateral vocal cord paralysis. Complications are uncommon when the procedure is performed by an experienced surgeon. The thyroid produces several hormones, such as thyroxine (T4), triiodothyronine (T3), and calcitonin. After ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Thyroid Gland
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobe (anatomy), lobes. The lower two thirds of the lobes are connected by a thin band of Connective tissue, tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical Thyroid follicular cell#Location, thyroid follicle, lined with thyroid follicular cell, follicular cells (thyrocytes), and occasional parafollicular cells that surround a follicular lumen, lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormonestriiodothyronine, triiodothyronine (T3) and thyroid hormone, thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the basal metabolic rate, metabolic rate and protein biosynthesis, protein synthesis, and in children, growth and development. Calcitonin plays a role in ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Cricothyroid Muscle
The cricothyroid muscle is the only tensor muscle of the larynx aiding with phonation. It is innervated by the superior laryngeal nerve. Its action tilts the thyroid forward to help tense the vocal cords. Structure The cricothyroid muscle originates from the anterolateral aspect of the cricoid cartilage, and inserts to the inferior cornu and lower lamina of the thyroid cartilage. Innervation This muscle is the only laryngeal muscle innervated by the superior laryngeal branch of the vagus nerve known as the superior laryngeal nerve. Function The cricothyroid muscle produces tension and elongation of the vocal cords. They draw up the arch of the cricoid cartilage and tilt back the upper border of the cricoid cartilage lamina. The distance between the vocal processes and the angle of the thyroid is increased, and the folds are consequently elongated, resulting in higher pitch phonation. They work as antagonists to the posterior cricoarytenoid muscles. Clinical significance ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Thyroid Cartilage
The thyroid cartilage is the largest of the nine cartilages that make up the ''laryngeal skeleton'', the cartilage structure in and around the trachea that contains the larynx. It does not completely encircle the larynx (only the cricoid cartilage encircles it). Structure The thyroid cartilage is a hyaline cartilage structure that sits in front of the larynx and above the thyroid gland. The cartilage is composed of two halves, which meet in the middle at a peak called the laryngeal prominence, also called the Adam's apple. In the midline above the prominence is the superior thyroid notch. A counterpart notch at the bottom of the cartilage is called the inferior thyroid notch. The two halves of the cartilage that make out the outer surfaces extend obliquely to cover the sides of the trachea. The posterior edge of each half articulates with the cricoid cartilage inferiorly at a joint called the cricothyroid joint. The most posterior part of the cartilage also has two projection ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Aryepiglottic Fold
The aryepiglottic folds are triangular folds of mucous membrane of the larynx. They enclose ligamentous and muscular fibres. They extend from the lateral borders of the epiglottis to the arytenoid cartilages, hence the name 'aryepiglottic'. They contain the aryepiglottic muscles and form the upper borders of the quadrangular membrane. They have a role in growling as a form of phonation. They may be narrowed and cause stridor, or be shortened and cause laryngomalacia. Structure The aryepiglottic folds are triangular. They are narrow in front, wide behind, and slope obliquely downward and backward. They originate from the lateral borders of the epiglottis. They insert into the arytenoid cartilages. In front, they are bounded by the epiglottis. Behind, they are bounded by the apices of the arytenoid cartilages, the corniculate cartilages, and the interarytenoid notch. Within the posterior part of each aryepiglottic fold exists a cuneiform cartilage which forms whitish promine ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Tongue
The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste buds housed in numerous lingual papillae. It is sensitive and kept moist by saliva and is richly supplied with nerves and blood vessels. The tongue also serves as a natural means of oral hygiene, cleaning the teeth. A major function of the tongue is the enabling of speech in humans and animal communication, vocalization in other animals. The human tongue is divided into two parts, an oral cavity, oral part at the front and a pharynx, pharyngeal part at the back. The left and right sides are also separated along most of its length by a vertical section of connective tissue, fibrous tissue (the lingual septum) that results in a groove, the median sulcus, on the tongue's surface. There are two groups of muscle ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Epiglottis
The epiglottis is a leaf-shaped flap in the throat that prevents food and water from entering the trachea and the lungs. It stays open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration of food into the lungs, forcing the swallowed liquids or food to go along the oesophagus toward the stomach instead. It is thus the valve that diverts passage to either the trachea or the oesophagus. The epiglottis is made of elastic cartilage covered with a mucous membrane, attached to the entrance of the larynx. It projects upwards and backwards behind the tongue and the hyoid bone. The epiglottis may be inflamed in a condition called epiglottitis, which is most commonly due to the vaccine-preventable bacteria ''Haemophilus influenzae''. Dysfunction may cause the inhalation of food, called aspiration, which may lead to pneumonia or airway obstruction. The epiglottis is also an important landmark for intubation. The epiglottis has been identif ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |