The thyroid gland is a butterfly-shaped endocrine gland located in the neck. It produces thyroid hormones triiodothyronine (T3) and thyroxine (T4) through a process involving iodine uptake, oxidation, and coupling reactions within thyroid follicles. The hormones are stored bound to thyroglobulin and later released into circulation, where they regulate metabolism through negative feedback on the hypothalamus and pituitary gland. The thyroid is supplied by superior and inferior thyroid arteries and drained by superior, middle, and inferior thyroid veins.
The document summarizes key aspects of larynx anatomy. It discusses:
1) The larynx functions to protect the lower respiratory tract, provide a controlled airway, and enable phonation, coughing, and lifting.
2) It consists of cartilages including the thyroid, cricoid, epiglottis, and arytenoid cartilages joined by membranes and ligaments.
3) Intrinsic muscles control the laryngeal inlet and vocal cord movements to modulate phonation, respiration, and protection of the airway.
Facial Nerve is one of the major nerves associated with the head and neck region. This presentation explains about its development, anatomy, and introduction on its clinical correlation.
This document provides an overview of the anatomy and embryology of the inner ear. It discusses the development of the inner ear from the otic placode and otocyst, and covers topics like the bony and membranous labyrinth, cochlea, vestibular system, inner ear fluids, blood supply, nerve supply, and surgical approaches to the inner ear. The overview is intended to inform the audience about the structure and development of this complex anatomical region.
The document discusses congenital lesions of the larynx that can occur during development. It describes how the larynx forms from the pharyngeal region between 4-10 weeks of gestation. Common congenital lesions include laryngomalacia (60%), vocal cord paralysis (20%), and subglottic stenosis (15%). Supraglottic lesions include laryngomalacia, laryngocoele, and cysts. Glottic lesions comprise vocal cord palsy, webs, and stenosis. Subglottic abnormalities are stenosis, hemangioma, and webs. Clinical features, diagnosis, and management are outlined for each condition. Flexible laryngoscopy is important for diagnosis while treatment
The document describes the anatomy and clinical features of the external auditory canal. It discusses the following key points:
- The external auditory canal has both cartilaginous and bony portions, with the bony portion making up the medial two-thirds. It is lined by skin that grows obliquely to prevent blockage.
- Aural atresia is the absence or closure of the external auditory canal. It can be congenital or acquired. Types include minor, moderate, and severe aplasia. Surgery aims to reconstruct the canal but has risks.
- Acquired atresia is due to inflammation, trauma, burns or previous ear surgery. It can be solid from
The document discusses the anatomy and development of the larynx. It describes the larynx's location and cartilages, including the thyroid, cricoid, epiglottis, and arytenoid cartilages. It also discusses the differences between a child's larynx and an adult larynx. The larynx develops from the foregut and surrounding mesoderm and descends in the neck during early childhood. It has three parts: the supraglottis, glottis, and subglottis, which contain various structures like the true and false vocal cords.
The document summarizes the anatomy and development of the inner ear. It discusses the embryological development from otic placodes to the formation of the membranous labyrinth. The inner ear anatomy includes the bony labyrinth containing the vestibule, semicircular canals and cochlea, as well as the membranous labyrinth containing the cochlear duct, utricle, saccule and endolymphatic structures. The organ of Corti is described as the sensory receptor organ of the cochlea containing inner and outer hair cells. The mechanism of hearing is also briefly outlined involving mechanical conduction of sound and the traveling wave theory of sound transmission in the cochle
This document provides an overview of ossicular prosthesis for ossicular chain reconstruction. It discusses the etiology of ossicular disruption, classifications of ossicular discontinuity, preoperative assessment, contraindications, available prosthesis materials including autogenous incus, cortical bone, cartilage, and biocompatible materials. It describes partial ossicular replacement prostheses and total ossicular replacement prostheses, along with options for each. Key factors for success include the status of the ossicular chain and middle ear mucosa. The goal of reconstruction is to improve hearing to within 15 dB of the normal ear.
The document summarizes key aspects of larynx anatomy. It discusses:
1) The larynx functions to protect the lower respiratory tract, provide a controlled airway, and enable phonation, coughing, and lifting.
2) It consists of cartilages including the thyroid, cricoid, epiglottis, and arytenoid cartilages joined by membranes and ligaments.
3) Intrinsic muscles control the laryngeal inlet and vocal cord movements to modulate phonation, respiration, and protection of the airway.
Facial Nerve is one of the major nerves associated with the head and neck region. This presentation explains about its development, anatomy, and introduction on its clinical correlation.
This document provides an overview of the anatomy and embryology of the inner ear. It discusses the development of the inner ear from the otic placode and otocyst, and covers topics like the bony and membranous labyrinth, cochlea, vestibular system, inner ear fluids, blood supply, nerve supply, and surgical approaches to the inner ear. The overview is intended to inform the audience about the structure and development of this complex anatomical region.
The document discusses congenital lesions of the larynx that can occur during development. It describes how the larynx forms from the pharyngeal region between 4-10 weeks of gestation. Common congenital lesions include laryngomalacia (60%), vocal cord paralysis (20%), and subglottic stenosis (15%). Supraglottic lesions include laryngomalacia, laryngocoele, and cysts. Glottic lesions comprise vocal cord palsy, webs, and stenosis. Subglottic abnormalities are stenosis, hemangioma, and webs. Clinical features, diagnosis, and management are outlined for each condition. Flexible laryngoscopy is important for diagnosis while treatment
The document describes the anatomy and clinical features of the external auditory canal. It discusses the following key points:
- The external auditory canal has both cartilaginous and bony portions, with the bony portion making up the medial two-thirds. It is lined by skin that grows obliquely to prevent blockage.
- Aural atresia is the absence or closure of the external auditory canal. It can be congenital or acquired. Types include minor, moderate, and severe aplasia. Surgery aims to reconstruct the canal but has risks.
- Acquired atresia is due to inflammation, trauma, burns or previous ear surgery. It can be solid from
The document discusses the anatomy and development of the larynx. It describes the larynx's location and cartilages, including the thyroid, cricoid, epiglottis, and arytenoid cartilages. It also discusses the differences between a child's larynx and an adult larynx. The larynx develops from the foregut and surrounding mesoderm and descends in the neck during early childhood. It has three parts: the supraglottis, glottis, and subglottis, which contain various structures like the true and false vocal cords.
The document summarizes the anatomy and development of the inner ear. It discusses the embryological development from otic placodes to the formation of the membranous labyrinth. The inner ear anatomy includes the bony labyrinth containing the vestibule, semicircular canals and cochlea, as well as the membranous labyrinth containing the cochlear duct, utricle, saccule and endolymphatic structures. The organ of Corti is described as the sensory receptor organ of the cochlea containing inner and outer hair cells. The mechanism of hearing is also briefly outlined involving mechanical conduction of sound and the traveling wave theory of sound transmission in the cochle
This document provides an overview of ossicular prosthesis for ossicular chain reconstruction. It discusses the etiology of ossicular disruption, classifications of ossicular discontinuity, preoperative assessment, contraindications, available prosthesis materials including autogenous incus, cortical bone, cartilage, and biocompatible materials. It describes partial ossicular replacement prostheses and total ossicular replacement prostheses, along with options for each. Key factors for success include the status of the ossicular chain and middle ear mucosa. The goal of reconstruction is to improve hearing to within 15 dB of the normal ear.
Physiology and neuroanatomy of phonationLenovo vibe
This document discusses the physiology and neuroanatomy of phonation. It describes the anatomy of the larynx including the vocal folds and their layers. It discusses the muscles that control vocal fold movement and the innervation of the larynx from the brain. It explains the process of voluntary vocalization and the vibratory cycle of the vocal folds during phonation. Factors that influence fundamental frequency, loudness, and registers are described. Causes of dysphonia like vocal fold palsy and presbylaryngis are mentioned. The importance of voice therapy and rest for reducing vocal stress is highlighted.
The document describes the anatomy of the larynx. It covers the development, skeletal framework including cartilages, subdivisions, muscles, histology, blood supply, nerve supply, lymphatic drainage and applied anatomy of the larynx. Key points include the cartilages that make up the skeletal framework, the intrinsic and extrinsic muscles that control movement and phonation, the nerve and blood supply, and common congenital anomalies and pathologies of the larynx.
This document discusses vocal cord paralysis, including:
1. It reviews the anatomy of the vocal cords and their innervation.
2. It outlines the various etiologies of vocal cord paralysis including neurological, tumor infiltration, systemic disease, medications, trauma, and idiopathic causes. Surgical procedures are a common traumatic cause.
3. It describes the evaluation of a patient with vocal cord paralysis including history, physical exam, imaging, and laryngeal electromyography to determine the location and cause of the paralysis.
The document provides an overview of the anatomy of the larynx, including:
- The larynx contains 9 cartilages (3 paired and 3 unpaired) connected by ligaments and containing 8 muscles.
- The cartilages include the thyroid, cricoid, epiglottis, and 3 pairs of smaller cartilages. Ligaments connect the cartilages and attach the larynx to surrounding structures.
- During swallowing, intrinsic and extrinsic muscles work together to elevate the larynx and close the glottis to prevent food from entering the trachea.
- The vocal folds and their tension, controlled by muscles, allow the larynx to function in
This document provides information on various benign vocal cord lesions including vocal nodules, vocal polyps, Reinke's edema, intubation granuloma, contact ulcer, laryngeal cysts, sulci, amyloidosis, and laryngeal keratosis. It describes the causes, symptoms, examination findings, and treatment options for each condition. The treatment may involve voice therapy, medical management, or surgical procedures like excision or laser ablation depending on the severity and type of lesion present. The goal of treatment is typically to resolve symptoms and prevent recurrence.
Surgical Management of Nasal Valve Insufficiency .pptxGierelma J.T.
This document discusses the surgical management of nasal valve insufficiency. There are multiple techniques used to address internal and external nasal valve collapse, including spreader grafts, butterfly grafts, batten grafts, and lateral crural strut grafts. For the external valve, techniques include lateral crural repositioning and strut graft placement to provide support to the lateral wall. Surgical management aims to improve nasal breathing and patency by strengthening weak nasal wall structures and correcting structural abnormalities.
This document provides an overview of the anatomy and embryology of the larynx. It describes the development of the larynx from the pharyngeal arches and foregut. The framework of the larynx is composed of cartilage, including the thyroid, cricoid, epiglottis and arytenoid cartilages. Ligaments such as the thyrohyoid connect the laryngeal cartilages to each other and surrounding structures. The larynx has extrinsic muscles that control its movement and intrinsic muscles that control vocal fold tension.
This document discusses the physiology of phonation, or voice production. It defines phonation as the rapid opening and closing of the vocal cords due to the separation and apposition of the vocal folds, accompanied by breath under lung pressure, which creates vocal sound. It describes the anatomy involved in voice production including the lungs, diaphragm, larynx, throat, mouth and nose. It discusses theories of voice production and covers topics like pitch, volume, quality, vocal registers, vocal disorders, vocal injury, and video stroboscopy.
Parotid tumour n management dr karan r rawatKaran Rawat
Dr. Beth Eselm Finseyoum discusses parotid gland tumors and their treatment. The parotid gland is located in front of the ear and contains the facial nerve. Common tumors include pleomorphic adenoma and Warthin's tumor, which are usually benign. Mucoepidermoid carcinoma is the most common malignant tumor. Investigation may include ultrasound, CT scan and MRI. Treatment depends on tumor type, grade and extent, and may involve surgery such as parotidectomy or radiotherapy. Outcomes vary depending on tumor aggressiveness, with malignant tumors having a poorer prognosis.
This document provides information on the anatomy of the external, middle, and inner ear. It begins with an overview of the external ear including the pinna, external acoustic canal, and tympanic membrane. It then discusses the anatomy of the middle ear, including the eustachian tube, tympanic cavity, ossicles, muscles, nerves, and blood supply. Finally, it covers the anatomy of the inner ear, including the bony and membranous labyrinths, semicircular canals, cochlea, hair cells, and receptors for hearing and balance. Clinical conditions involving each part of the ear are also briefly mentioned.
The document summarizes the development of the nose from the 4th to 8th week of intrauterine life. It describes how nasal placodes appear and invaginate to form nasal pits and prominences. The prominences divide and are compressed by growing maxillary prominences. Ethmoid turbinates then develop ridges on the lateral nasal wall that form various structures like the agger nasi and uncinate process. Furrows between the turbinates form the different nasal meatuses. The document also lists some common developmental anomalies of the nose like proboscis deformity, arhinia, and cleft lip and palate.
A vocal cord granuloma is a benign growth that forms on the vocal cords due to irritation or trauma from vocal use or acid reflux. It causes hoarseness, voice breaks, and a sensation of something in the throat. Treatment involves controlling acid reflux through diet, medication, and voice therapy to address harmful vocal behaviors. Surgery is usually a last resort as granulomas often resolve with proper medical management and lifestyle changes to avoid further irritation and trauma to the vocal cords.
This document discusses the management of a 19-year-old patient with recurrent laryngotracheal stenosis following emergency intubation for acute organophosphate poisoning 2 months prior. It establishes the diagnosis of laryngotracheal stenosis through history and examination. It then discusses evaluating the severity and progression, as well as investigations including direct laryngoscopy. Finally, it outlines management approaches such as endolaryngeal procedures like dilation and LASER, open procedures like tracheal resection and anastomosis, as well as adjunct treatments and follow up.
The larynx protects the lower respiratory tract, provides a controlled airway, and allows for phonation and coughing. During embryonic development, the larynx develops from structures in the pharynx and sixth pharyngeal arch. As an adult, the larynx extends from the laryngeal inlet to the cricoid cartilage and is divided into supraglottis, glottis, and subglottis. It contains cartilages, ligaments, muscles, and mucous membranes. The intrinsic muscles control vocal fold adduction except for the cricothyroid muscle. Phonation is initiated by vocal fold abduction and adduction controlled by the lateral cricoarytenoid muscles, with vocal fold
The document discusses the anatomy of the larynx. It describes the cartilages that make up the larynx, including the thyroid, cricoid, epiglottis, and others. It discusses the joints and membranes in the larynx. It also summarizes the intrinsic and extrinsic muscles that control the larynx, as well as the blood supply, nerve supply, and embryonic development of the larynx.
Pharyngocutaneous fistula after total laryngectomy Dr. M. Eramimderami
1) Pharyngocutaneous fistulas are a common complication after total laryngectomy and are more likely in patients who received radiation therapy or have medical comorbidities like diabetes.
2) Conservative management is usually attempted first using antibiotics, no oral intake, and wound care but may fail, requiring surgical closure.
3) Studies have found that hyperbaric oxygen therapy can successfully close pharyngocutaneous fistulas in a high percentage (87.5% in one study) of cases that failed conservative management.
The inner ear first appears as auditory placodes that form hollow otocysts on the 24th day of embryo formation. By the 7th week, the otocyst has developed into the membranous labyrinth containing the semicircular canals and a single turn cochlea. By the 12th week, the adult form of the inner ear is nearly complete, with the membranous labyrinth suspended in perilymph within the developing bony labyrinth. A full understanding of inner ear embryology is important for treating hearing issues that result from prenatal development problems or cochlear damage in adulthood.
The document provides an overview of the inner ear anatomy and physiology. It describes the cochlea as a snail-shaped bony structure that is coiled around a central axis. Within the cochlea lies the membranous labyrinth, which contains three fluid-filled scalae separated by membranes. Sound causes vibrations that move fluids and stimulate hair cells in the organ of Corti. Inner hair cells detect sound and transmit signals, while outer hair cells amplify these signals. Key structures that enable hearing include the stria vascularis, which generates the endocochlear potential providing energy, and potassium circulation pathways that are essential for normal cochlear function.
The cavernous sinus is located in the middle cranial fossa on either side of the body of the sphenoid bone and sella turcica. It contains the internal carotid artery and cranial nerves III, IV, V1, and VI. The cavernous sinus drains into the angular vein, pterygoid venous plexus, and intercavernous sinuses which connect the two cavernous sinuses. Clinical implications include spread of infection or thrombosis from the face into the cavernous sinus via connections to facial veins.
The thyroid gland is located in the neck and produces thyroid hormones that regulate metabolism. It consists of two lobes connected by an isthmus. During development it arises from an endodermal diverticulum. The thyroid traps iodine from the blood and uses it along with the amino acid tyrosine to produce the hormones thyroxine (T4) and triiodothyronine (T3) via a series of coupling reactions within the thyroid follicles. T4 makes up 90% of secretion but T3 is the active hormone. Thyroid hormone production is regulated by TSH from the pituitary gland.
- The thyroid gland develops from an endodermal diverticulum in the floor of the pharynx that migrates to its final position in the neck.
- It is located in the anterior neck, below the larynx and trachea, and consists of two lobes connected by an isthmus.
- The thyroid gland is highly vascular and receives its blood supply from the superior and inferior thyroid arteries. Its veins drain into the internal jugular and brachiocephalic veins.
Physiology and neuroanatomy of phonationLenovo vibe
This document discusses the physiology and neuroanatomy of phonation. It describes the anatomy of the larynx including the vocal folds and their layers. It discusses the muscles that control vocal fold movement and the innervation of the larynx from the brain. It explains the process of voluntary vocalization and the vibratory cycle of the vocal folds during phonation. Factors that influence fundamental frequency, loudness, and registers are described. Causes of dysphonia like vocal fold palsy and presbylaryngis are mentioned. The importance of voice therapy and rest for reducing vocal stress is highlighted.
The document describes the anatomy of the larynx. It covers the development, skeletal framework including cartilages, subdivisions, muscles, histology, blood supply, nerve supply, lymphatic drainage and applied anatomy of the larynx. Key points include the cartilages that make up the skeletal framework, the intrinsic and extrinsic muscles that control movement and phonation, the nerve and blood supply, and common congenital anomalies and pathologies of the larynx.
This document discusses vocal cord paralysis, including:
1. It reviews the anatomy of the vocal cords and their innervation.
2. It outlines the various etiologies of vocal cord paralysis including neurological, tumor infiltration, systemic disease, medications, trauma, and idiopathic causes. Surgical procedures are a common traumatic cause.
3. It describes the evaluation of a patient with vocal cord paralysis including history, physical exam, imaging, and laryngeal electromyography to determine the location and cause of the paralysis.
The document provides an overview of the anatomy of the larynx, including:
- The larynx contains 9 cartilages (3 paired and 3 unpaired) connected by ligaments and containing 8 muscles.
- The cartilages include the thyroid, cricoid, epiglottis, and 3 pairs of smaller cartilages. Ligaments connect the cartilages and attach the larynx to surrounding structures.
- During swallowing, intrinsic and extrinsic muscles work together to elevate the larynx and close the glottis to prevent food from entering the trachea.
- The vocal folds and their tension, controlled by muscles, allow the larynx to function in
This document provides information on various benign vocal cord lesions including vocal nodules, vocal polyps, Reinke's edema, intubation granuloma, contact ulcer, laryngeal cysts, sulci, amyloidosis, and laryngeal keratosis. It describes the causes, symptoms, examination findings, and treatment options for each condition. The treatment may involve voice therapy, medical management, or surgical procedures like excision or laser ablation depending on the severity and type of lesion present. The goal of treatment is typically to resolve symptoms and prevent recurrence.
Surgical Management of Nasal Valve Insufficiency .pptxGierelma J.T.
This document discusses the surgical management of nasal valve insufficiency. There are multiple techniques used to address internal and external nasal valve collapse, including spreader grafts, butterfly grafts, batten grafts, and lateral crural strut grafts. For the external valve, techniques include lateral crural repositioning and strut graft placement to provide support to the lateral wall. Surgical management aims to improve nasal breathing and patency by strengthening weak nasal wall structures and correcting structural abnormalities.
This document provides an overview of the anatomy and embryology of the larynx. It describes the development of the larynx from the pharyngeal arches and foregut. The framework of the larynx is composed of cartilage, including the thyroid, cricoid, epiglottis and arytenoid cartilages. Ligaments such as the thyrohyoid connect the laryngeal cartilages to each other and surrounding structures. The larynx has extrinsic muscles that control its movement and intrinsic muscles that control vocal fold tension.
This document discusses the physiology of phonation, or voice production. It defines phonation as the rapid opening and closing of the vocal cords due to the separation and apposition of the vocal folds, accompanied by breath under lung pressure, which creates vocal sound. It describes the anatomy involved in voice production including the lungs, diaphragm, larynx, throat, mouth and nose. It discusses theories of voice production and covers topics like pitch, volume, quality, vocal registers, vocal disorders, vocal injury, and video stroboscopy.
Parotid tumour n management dr karan r rawatKaran Rawat
Dr. Beth Eselm Finseyoum discusses parotid gland tumors and their treatment. The parotid gland is located in front of the ear and contains the facial nerve. Common tumors include pleomorphic adenoma and Warthin's tumor, which are usually benign. Mucoepidermoid carcinoma is the most common malignant tumor. Investigation may include ultrasound, CT scan and MRI. Treatment depends on tumor type, grade and extent, and may involve surgery such as parotidectomy or radiotherapy. Outcomes vary depending on tumor aggressiveness, with malignant tumors having a poorer prognosis.
This document provides information on the anatomy of the external, middle, and inner ear. It begins with an overview of the external ear including the pinna, external acoustic canal, and tympanic membrane. It then discusses the anatomy of the middle ear, including the eustachian tube, tympanic cavity, ossicles, muscles, nerves, and blood supply. Finally, it covers the anatomy of the inner ear, including the bony and membranous labyrinths, semicircular canals, cochlea, hair cells, and receptors for hearing and balance. Clinical conditions involving each part of the ear are also briefly mentioned.
The document summarizes the development of the nose from the 4th to 8th week of intrauterine life. It describes how nasal placodes appear and invaginate to form nasal pits and prominences. The prominences divide and are compressed by growing maxillary prominences. Ethmoid turbinates then develop ridges on the lateral nasal wall that form various structures like the agger nasi and uncinate process. Furrows between the turbinates form the different nasal meatuses. The document also lists some common developmental anomalies of the nose like proboscis deformity, arhinia, and cleft lip and palate.
A vocal cord granuloma is a benign growth that forms on the vocal cords due to irritation or trauma from vocal use or acid reflux. It causes hoarseness, voice breaks, and a sensation of something in the throat. Treatment involves controlling acid reflux through diet, medication, and voice therapy to address harmful vocal behaviors. Surgery is usually a last resort as granulomas often resolve with proper medical management and lifestyle changes to avoid further irritation and trauma to the vocal cords.
This document discusses the management of a 19-year-old patient with recurrent laryngotracheal stenosis following emergency intubation for acute organophosphate poisoning 2 months prior. It establishes the diagnosis of laryngotracheal stenosis through history and examination. It then discusses evaluating the severity and progression, as well as investigations including direct laryngoscopy. Finally, it outlines management approaches such as endolaryngeal procedures like dilation and LASER, open procedures like tracheal resection and anastomosis, as well as adjunct treatments and follow up.
The larynx protects the lower respiratory tract, provides a controlled airway, and allows for phonation and coughing. During embryonic development, the larynx develops from structures in the pharynx and sixth pharyngeal arch. As an adult, the larynx extends from the laryngeal inlet to the cricoid cartilage and is divided into supraglottis, glottis, and subglottis. It contains cartilages, ligaments, muscles, and mucous membranes. The intrinsic muscles control vocal fold adduction except for the cricothyroid muscle. Phonation is initiated by vocal fold abduction and adduction controlled by the lateral cricoarytenoid muscles, with vocal fold
The document discusses the anatomy of the larynx. It describes the cartilages that make up the larynx, including the thyroid, cricoid, epiglottis, and others. It discusses the joints and membranes in the larynx. It also summarizes the intrinsic and extrinsic muscles that control the larynx, as well as the blood supply, nerve supply, and embryonic development of the larynx.
Pharyngocutaneous fistula after total laryngectomy Dr. M. Eramimderami
1) Pharyngocutaneous fistulas are a common complication after total laryngectomy and are more likely in patients who received radiation therapy or have medical comorbidities like diabetes.
2) Conservative management is usually attempted first using antibiotics, no oral intake, and wound care but may fail, requiring surgical closure.
3) Studies have found that hyperbaric oxygen therapy can successfully close pharyngocutaneous fistulas in a high percentage (87.5% in one study) of cases that failed conservative management.
The inner ear first appears as auditory placodes that form hollow otocysts on the 24th day of embryo formation. By the 7th week, the otocyst has developed into the membranous labyrinth containing the semicircular canals and a single turn cochlea. By the 12th week, the adult form of the inner ear is nearly complete, with the membranous labyrinth suspended in perilymph within the developing bony labyrinth. A full understanding of inner ear embryology is important for treating hearing issues that result from prenatal development problems or cochlear damage in adulthood.
The document provides an overview of the inner ear anatomy and physiology. It describes the cochlea as a snail-shaped bony structure that is coiled around a central axis. Within the cochlea lies the membranous labyrinth, which contains three fluid-filled scalae separated by membranes. Sound causes vibrations that move fluids and stimulate hair cells in the organ of Corti. Inner hair cells detect sound and transmit signals, while outer hair cells amplify these signals. Key structures that enable hearing include the stria vascularis, which generates the endocochlear potential providing energy, and potassium circulation pathways that are essential for normal cochlear function.
The cavernous sinus is located in the middle cranial fossa on either side of the body of the sphenoid bone and sella turcica. It contains the internal carotid artery and cranial nerves III, IV, V1, and VI. The cavernous sinus drains into the angular vein, pterygoid venous plexus, and intercavernous sinuses which connect the two cavernous sinuses. Clinical implications include spread of infection or thrombosis from the face into the cavernous sinus via connections to facial veins.
The thyroid gland is located in the neck and produces thyroid hormones that regulate metabolism. It consists of two lobes connected by an isthmus. During development it arises from an endodermal diverticulum. The thyroid traps iodine from the blood and uses it along with the amino acid tyrosine to produce the hormones thyroxine (T4) and triiodothyronine (T3) via a series of coupling reactions within the thyroid follicles. T4 makes up 90% of secretion but T3 is the active hormone. Thyroid hormone production is regulated by TSH from the pituitary gland.
- The thyroid gland develops from an endodermal diverticulum in the floor of the pharynx that migrates to its final position in the neck.
- It is located in the anterior neck, below the larynx and trachea, and consists of two lobes connected by an isthmus.
- The thyroid gland is highly vascular and receives its blood supply from the superior and inferior thyroid arteries. Its veins drain into the internal jugular and brachiocephalic veins.
The document discusses the development, anatomy, physiology and surgical importance of the thyroid and parathyroid glands. It describes how the thyroid gland develops from an epithelial proliferation in the pharynx and descends to its final position in front of the trachea. It discusses the relations, blood supply including the superior and inferior thyroid arteries, lymphatic drainage and innervation including the recurrent laryngeal nerve. The physiology section explains thyroid hormone synthesis and regulation by TSH and TRH.
The thyroid gland is located in the lower front of the neck. It consists of two lobes connected by an isthmus. The lobes extend from the oblique line of the thyroid cartilage to the 4th-6th tracheal rings. The thyroid is highly vascular, receiving blood supply from the superior and inferior thyroid arteries. The recurrent laryngeal nerves pass behind the branches of the inferior thyroid artery and enter the larynx. Care must be taken during thyroid surgery to identify and preserve these structures to avoid complications.
Surgical anatomy and physiology of thyroid and parathyroidAjayKumar4497
The document discusses the development, anatomy, relations, blood supply, lymphatic drainage, nerve supply and physiology of the thyroid and parathyroid glands. It describes how the thyroid gland develops and migrates in the embryo. It can have developmental anomalies like thyroglossal cysts. The basic anatomy of the thyroid including its lobes, relations and parts are explained. The arterial supply from superior and inferior thyroid arteries and venous drainage are summarized. The lymphatic drainage and nerve supply including the recurrent laryngeal nerve are highlighted. Cernea's classification of the external branch of superior laryngeal nerve and the space of Reeves are mentioned in the context of thyroid surgery. The physiology of thyroid hormones T4, T3
This document provides an overview of the anatomy of the thyroid gland, including its development, gross anatomy, blood supply, nerve supply, lymphatic drainage, histology, and applied anatomy. It begins with an introduction to the thyroid gland and its hormone functions. It then discusses the gland's development from an endodermal thickening in the pharynx. The document provides detailed descriptions of the gland's location, shape, size, relations to surrounding structures, capsules, arterial supply, venous drainage, innervation, and histology. It concludes with examples of clinical applications regarding thyroid disorders.
The Endocrine System in the Head and NeckHadi Munib
The document discusses several endocrine glands in the head and neck region, including the pituitary gland, pineal gland, thyroid gland, and parathyroid glands. It provides details on the location, blood supply, nerve supply, and functions of each gland. It also describes the root of the neck and key muscles and vascular structures in that area, such as the scalene muscles, subclavian artery, and subclavian vein.
ANATOMY OF LARYNX, VOCAL CORD PALSIES ,.pptxzaaprotta
Anatomy of the Larynx
Cartilaginous Framework and Ligaments:
The larynx consists of several cartilages, both unpaired and paired:
Unpaired Cartilages:
Thyroid Cartilage: The largest laryngeal cartilage, it forms the anterior and lateral portions of the larynx. The prominent anterior projection is commonly known as the “Adam’s apple.”
Cricoid Cartilage: Located below the thyroid cartilage, it forms a complete ring.
Epiglottis: A leaf-shaped cartilage that covers the larynx during swallowing to prevent food aspiration.
Paired Cartilages:
Arytenoid Cartilages: These play a crucial role in vocal fold movement.
Corniculate Cartilages: Sit atop the arytenoids.
Cuneiform Cartilages: Found within the aryepiglottic folds.
Cervical Viscera lecture delivered by Saad DattiSadiq787794
The document summarizes the anatomy of the cervical viscera, including the thyroid gland, parathyroid glands, larynx, and trachea. It notes that the cervical viscera are arranged in three layers - endocrine, respiratory, and alimentary. The endocrine layer includes the thyroid and parathyroid glands. The respiratory layer contains the larynx and trachea. The alimentary layer comprises the pharynx and esophagus. It then provides detailed descriptions of the anatomy, blood supply, nerve supply, and functions of the thyroid gland and larynx.
Anatomy and Embryology of thyroid and Parathyroid Glands 20.1.2022 Prof Dr Mo...DodoHamid
- The thyroid and parathyroid glands develop from the endoderm of the pharynx and migrate to their final locations in the neck.
- The thyroid gland consists of right and left lobes connected by an isthmus, located anterior to the trachea. It is highly vascular and innervated by branches of the inferior thyroid artery and recurrent laryngeal nerve.
- The parathyroid glands are usually four in number, located on the posterior surface of the thyroid gland. They are supplied by branches of the inferior thyroid artery and drain into thyroid veins.
- Upon completion of the lecture, students should be able to describe the anatomy and embryology of the thyroid and parathyroid glands,
- The thyroid gland develops from the median anlage and two lateral anlagen in the neck during gestation.
- It has two lobes connected by an isthmus and is located in the front of the neck below the larynx. It is supplied by superior and inferior thyroid arteries.
- Thyroidectomy is commonly performed to treat thyroid disorders like hyperthyroidism or cancer. The surgery involves mobilizing and removing all or part of the thyroid gland while protecting structures like the recurrent laryngeal nerves and parathyroid glands. Post-operative care focuses on monitoring for complications and replacing thyroid hormone treatment as needed.
Embryology and Anatomy of Thyroid Gland.pptxZryanMejio1
The thyroid gland develops from endodermal tissue in the pharynx between the first and second pharyngeal pouches. It descends to its final location in front of the trachea by the 7th week of gestation. The thyroid is normally bilobed and located in the lower neck, extending from the C5 to T1 vertebrae. It receives its blood supply from the superior and inferior thyroid arteries and drains via superior, middle, and inferior thyroid veins. The recurrent laryngeal nerves pass close to the thyroid and are at risk during surgery.
This document provides a summary of a seminar on the surgical anatomy of the neck, thyroid, and parathyroid gland. It begins with a discussion of embryology, including the development of the pharyngeal arches, pouches, and thyroid and parathyroid glands. It then covers topics such as the blood supply, innervation, and relations of important structures like the recurrent laryngeal nerve. Congenital anomalies are also discussed. The aim is to provide surgeons with an anatomical guide to structures in the neck region.
The thyroid gland is located in the neck below the larynx. It consists of two lobes connected by an isthmus and weighs 10-20 grams in adults. The thyroid has an abundant blood supply from the superior and inferior thyroid arteries. It drains into the internal jugular veins. The recurrent laryngeal nerves pass under the thyroid and are at risk during surgery. The thyroid plays an important role in regulating metabolism through production of thyroid hormones. Diseases like Graves' disease and hypothyroidism affect thyroid function. The parathyroid glands regulate calcium levels and are located near the thyroid.
The document summarizes key information about the thyroid and suprarenal glands. It describes the location, structure, blood supply, development, and functions of the thyroid gland. It also discusses common pathologies of the thyroid gland like goiter and hyperthyroidism/hypothyroidism. For the suprarenal glands, it outlines their location in the abdomen, histological structure consisting of the cortex and medulla, hormone production, blood supply and applied clinical implications like Cushing's syndrome and Conn's syndrome.
The document provides information on a seminar about cancer of the thyroid gland including:
1. Brief embryology, surgical anatomy, blood supply, lymph drainage and histology of the thyroid gland.
2. Introduction and classification of thyroid cancer focusing on differentiated thyroid cancer including papillary and follicular thyroid carcinoma.
3. Discussion of the epidemiology, risk factors, pathology, molecular genetics, clinical assessment, investigations and staging of differentiated thyroid cancer.
4. Overview of treatment approaches for differentiated thyroid cancer including surgery, radioactive iodine ablation and thyroxine suppressive therapy.
The thyroid gland is a butterfly-shaped endocrine gland located in the front of the neck. It is composed of two lobes connected by an isthmus and develops early in gestation from the floor of the pharynx. The thyroid secretes thyroid hormones that influence metabolism and growth and the peptide hormone calcitonin, which regulates calcium levels. Microscopically, it contains follicles lined with follicular cells that secrete thyroid hormones into the follicular colloid and scattered parafollicular cells that secrete calcitonin. Disorders of the thyroid include hyperthyroidism, hypothyroidism, inflammation, enlargement, and cancer.
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The facial nerve, also known as cranial nerve VII, is one of the 12 cranial nerves originating from the brain. It's a mixed nerve, meaning it contains both sensory and motor fibres, and it plays a crucial role in controlling various facial muscles, as well as conveying sensory information from the taste buds on the anterior two-thirds of the tongue.
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4. • Butterfly/H shaped
• Brownish-Red
• Highly vascular
• Ductless gland
• Adult gland weighing 20 to 25gm.
• Larger in female
• Enlarges further during puberty, menstruation
& pregnancy
5. • Consist of right and left cone shaped lobes
5*3*2cm
• Connectedbya narrowregionof gland -Isthmus
1.2*1.2cm
• Situated anteriorly in the visceral
compartment of the neck at the level of C5-T1
vertebrae
7. DEVELOPMENT OF THYROID GLAND
• Median endodermal thyroiddiverticulum(median
anlage)
Foramencaecum
Thyroglossal duct(usually reabsorbed after
6 weeks of age)
The very distal end of this remnant may be
retained and mature as a pyramidal lobe in the
adult thyroid
8. THE THYROID begins to function- end of 3month,
at which time, the first follicles containing colloid
can be seen
• Ultimobranchial body gives parafollicular C cells
to thyroid gland - Parafollicular cells(C cells) from
theneuralcrest reachthethyroidviatheultimobranchial
body- arises from 4th & 5th Brachial pouch.
• Superior parathyroid gland- arises from 4th
Brachial pouch.
11. • A lateral or posterior projection of the thyroid
lobe,
known as the tubercle of Zuckerkandl, identified
in
up to 60 % of surgical dissections
• It is represent the point of embryological fusion
of the ultimobranchial body and median
anlage.
Its surgical importance is :
(a) RLN runs medial to it;
(b)the superior parathyroid gland attached to its
cranial aspect;
12. CAPSULES
• True capsule (fibrous) – contains
the parenchyma & sends fine
septae between lobules of the
thyroidgland.
• Arteries and plexusof veinsdeep
toit
• Falsecapsule–pretracheal fascia
14. Suspensory ligament ofberry
The pretracheal layer is
thin alongthe posterior
border of the lobes, but
thickon theinner surface
ofthegland where it
forms a suspensory
ligament of berrywhich
connects the gland to the
cricoidcartilage
15. Why thyroid moves withdeglutition?
• During 1ststageofdeglutition
• Hyoid bone movesup
• Pullspre-trachealfasciaup
• This pulls ligament ofberryupward
• This pulls thyroidupward
16. • A fibromuscular band levatorglandulaethyroideae
descend from the body of the hyoid bone to
isthmus ortopyramidal lobe
17. RELATIO
NS
• The lobes are conical in shape having
– Apex
– Base
– Three surfaces : Lateral, Medial, Posterolateral
– Two borders : Anterior & posterior
18. • APEX: Directed upward & slightly laterally.
limited superiorly – sternothyroid on the oblique
line of thyroid cartilage
• BASE: At the level of 4th or 5th tracheal length
24. Blood
supply
Superior thyroid artery:
• 1st anterior branch of external
carotid artery
• Runs downwards & forward
with close relation with
external laryngeal nerve
• Pierces pretracheal fascia-
upper pole of lobe
anterior Posterior branch
25. • Anterior branch descends on the anterior border of
the lobe
anastomosing branch which runs along the upper
border of the isthmus to anastomosis with opp. side
26. • Posterior branch – Posterior border of the
lobe
Anastomosis with ascending
branch of inferior thyroid
artery
Superior thyroid artery
Supplies Upper 1/3rd of thelobe
Upper ½ of the isthmus
27. Inferior thyroid artery:
• Branch of thyrocervival trunk
Subclavian artery
• Runs forward then medially
& finally downward to reach
lower pole of the gland.
• Pass behind carotid sheath,
MiddleCervicalGanglionand in
front of vertebral vessels
• CloserelatedRecurrentlaryngeal
Nerve
28. • Artery divides into 4 or 5 Glandular branch
pierces the fascia separately to reach the lower
part of the gland
• Ascending branch anastomoses with posterior branch
of superior thyroid artery
Supply Parathyroid gland
Inferior thyroid artery
Supplies Lower 2/3rd of the lobe
Lower ½ of the isthmus & Parathyroid gland
29. THYROIDEA IMAARTERY
( lowest thyroidartery)
• 12 % present ascending in front
of the trachea to end at the
isthmus.
• most commonly arises from the
brachiocephalic artery
• it can also originate from the
aorta, the right common carotid,
subclavian or internal thoracic
arteries.
30. VENOUS DRAINAGE :
The superior, middle and inferior thyroid vein
Superior thyroid vein(STV)
• Accompany SupThyroidArtery
• Drain to IJV/ facialvein
31. Middle thyroidvein
• Veryshort, may be
double or absent.
• They receive blood
from the inferior
and antero-lateral
part of the gland as
well as the larynx
and trachea.
• most commonly
cross the common
carotid artery
• Drain to IJV
34. LYMPHATIC DRAINAGE
The thyroid gland contains a rich network of lymphatics
The lateral aspects of the gland drain into levels III and IVand
those of the posterior triangle (level V).
The more medial aspects of the
gland also drain into the nodes
of the anterior compartment
of the
neck (level VI),
drain into those of the superior
mediastinum (level VII).
37. Recurrent laryngeal nerves
• The recurrent laryngeal nerve is variable in
size 1.5-4 mm in diameter.
• Identified by its
whitish appearance,
characteristic longitudinal vessel
flattened,
rounded surface.
In up to 39 % of cases the nerve divides into 2
(and occasionally up to 6) terminal branches
between 6 and 35 mm from the cricoid cartilage.
38. A non recurrent laryngeal nerve is found in 0.2-
0.4% of patients
It tends to be thicker than a normally sited
nerve
Usually associated with a vascular anomaly of
the subclavian artery on the right side
Transposition of the great vessels on the left
side.
39. Recurrent laryngeal nerves
• Branches of the vagus nerve, which
supply all the intrinsic muscles of the larynx
except the cricothyroid muscle.(External laryngeal
N – Superior Laryngeal N)
• They also supply sensory fibres to the mucous
membrane below the level of the vocal folds
• Accidental damage tothisnerveduring surgery
causes ipsilateralvocalcord paralysis& difficultyin
phonation
40. Left Recurrent laryngeal nerves
• The approximate length of the left RLN is 12
cms
•The nerve leaves the
vagus in the mediastinum
anterior to the arch of the
aorta passing behind the
ligamentum arteriosum &
then posteriorly under the
concavity of the arch before
passing superiorly to lie in
the tracheo-oesophageal
groove.
41. • It most usually passes
behind the inferior
thyroid artery
• Then posterior to the
ligament of Berry
before passing under or
between the fibres of
the cricopharyngeal part
of the inferior
constrictor
42. Right Recurrent laryngeal nerves
• The approximate length of right RLN 6 cms
•Rt side it originates
from vagus crosses
firstpartofsubclavian
artery.
•More oblique course
to the tracheo-
oesophageal groove.
43. SUPERIORLARYNGEALNERVE
• Arises from inferior ganglion of vagus
• Descends behind internal carotidartery
• At the level of greater cornua of hyoid it divides:-
Internal branch(sensory) Externalbranch(motor)
44.
45. • The external branch of the superior laryngeal
nerve, which supplies the cricothyroid muscle,
runs parallel to the superior thyroid vessels
• The Internal branch of the superior laryngeal
nerve supply sensory fibres to the mucous
membrane above the level of the vocal folds
46.
47. External branch of superior laryngeal nerve
and joll’s triangle
• Joll's triangle is used to identify the location
of external branch of superior laryngeal nerve
during thyroid surgeries.
• Damage to this nerve during the surgical
procedure may reduce the voice range in those
patients.
• This triangle is also known as
sternothyrolaryngeal triangle.
48. Boundaries of Joll's triangle :
Lateral - Upper pole of
thyroid gland and superior
thyroid vessels
Superior - Attachment of
the strap muscles and deep
investing layer of fascia to
the hyoid
Medial - Midline
Floor - Cricothyroid
muscle
External branch of superior laryngeal
nerve lies within this triangle.
49. Beahrs Triangle or Riddle’s triangle
Boundaries
Medial :The RL nerve in the
lower part of tracheo -
oesophageal groove
Lateral :Common carotid
Superior: Inferior thyroid
artery
50. Microscopic anatomy
• The thyroid gland consists mainly of follicular cells,
one cell thick around a central pool of colloid to form
follicles.
• The follicles spherical in shape & 0.02- 0.9 mm in
diameter
•A thyroid lobule
consists of 20 to 40
follicles and is supplied
by a lobular artery.
51. When the gland is relatively inactive, the cells
are flattened and the colloid is abundant, dense.
On prolonged and excessive TSH stimulation,
the follicular cells become hypertrophied and
hyperplastic and they adopt a more columnar
shape.
This cellular enlargement is associated with
development of microvilli which helps in reduction
in the size of the follicular lumen.
52.
53. PHYSIOLOGY OF THE THYROID
The thyroid folliclessecretestri-iodothyronine
(T3) and thyroxin(T4)
Synthesis involves combination of iodine with
tyrosine group toform mono anddi-iodotyrosine
which are coupledto form T3andT4.
Thehormones arestoredin folliclesbound to
thyrogobulin
54. When hormones released inthe blood they
are bound to plasma proteins andsmall
amountremain freein theplasma
Themetaboliceffectof thyroidhormones
are dueto free (unbound)T3 andT4.
90%of secretedhormones isT4butT3is
theactivehormone so,
T4is convertedtoT3peripherally.
55. Regulation of thyroid gland metabolism
-
CirculatingT3
and T4exert
- ve feedback
mechanism
on
hypothalamus
and anterior
pituitarygland
So, inhyperthyroidism
where hormone level
in blood is high ,TSH
production is
suppressed and
viceversa.
57. 1. Thyroglobulin Synthesis
• Endoplasmic reticulum and Golgi apparatus in
the
follicular cells of thyroid gland synthesize and
secrete thyroglobulin continuously.
• Thyroglobulin molecule is a large glycoprotein
containing 140 molecules of amino acid
tyrosine.
• After synthesis, thyroglobulin is stored in the
follicle.
58. 2. Iodinetrapping
Iodide is actively transported from blood
into follicular cell, against electrochemical
gradient. This process is called iodide
trapping.
Iodide is transported into the follicular cell
along with sodium by Sodium iodide (Na +
/ I-) symporter , which is also called iodide
pump. Whereby two sodium ions are
transported for each iodide ion.
59. The accumulated iodide in the follicular cells
is then transferred to the apical plasma
membrane down an electrochemical gradient.
TSH stimulation increases adenosine
triphosphate (ATP) and ATPase activity at
the apex of the cell increasing the efflux of
iodide into the colloid down a further electrical
gradient.
Iodine available through certain foods (eg,
seafood,bread,dairy products),iodizedsalt, or
dietary supplementsetc
60. 3. Oxidation of Iodide
• Iodide must be oxidized to elementary
iodine, because only iodine is capable of
combining with tyrosine to form thyroid
hormones.
• The oxidation of iodide into iodine occurs
inside the follicular cells in the presence
of thyroid peroxidase.
61. 4. Iodination of Tyrosine
• Iodine is transported from follicular cells into
the follicular cavity, where it binds with
thyroglobulin.
• Then, iodine (I) combines with tyrosine, which
is already present in thyroglobulin
• Tyrosine is iodized first into monoiodotyrosine
(MIT) and later into di-iodotyrosine (DIT)-
thyroglobulin (Tg)tyrosineresidues
62. 5. Coupling Reactions
i.One molecule of DIT and one molecule of MIT combine to
form tri-iodothyronine (T3)
DIT + MIT = Tri-iodothyronine (T3)
ii.One molecule of MIT and one molecule of DIT combine
to produce another form of T3 called reverse T3 or rT3.
Reverse T3 is only 1% of thyroid output
MIT + DIT = Reverse T3
iii.Two molecules of DIT combine to form
tetraiodothyronine (T4) thyroxine.
DIT + DIT = Tetraiodothyronine or Thyroxine (T4)
63.
64.
65. FUNCTIONS OF THYROID HORMONES
1. Action on basal metabolic rate (BMR)
Thyroidhormones (specificallyT3)regulaterate
of overall bodymetabolism
–T3 increases basalmetabolicrate
Calorigeniceffects
–T3increasesoxygenconsumptionbymost
peripheraltissues
–Increases bodyheatproduction
66. 2. Action on carbohydrate metabolism
• Thyroxine stimulates almost all processes involved
in
the metabolism of carbohydrate.
Thyroxine:
i. Increases the absorption of glucose from GI tract
ii.Enhances the glucose uptake by the cells, by
accelerating the transport of glucose through
the cell membrane
iii.Increases the breakdown of glycogen into
glucose
iv.Accelerates gluconeogenesis.
67. 3. Action on fat metabolism
Thyroxine decreases the fat storage by
mobilizing it from adipose tissues and fat
depots.
Thus, thyroxine increases the free fatty acid
level in blood.
68. 4.ActiononGrowthandDevelopment
• Thyroidhormone is essentialfor normal
braindevelopment
• Essentialfor childhoodgrowth
–Untreated congenital hypothyroidismor
chronic hypothyroidism during
childhood canresultin incomplete
developmentand mentalretardation
69. 5.ActiononCNS
• Thyroid hormones are essential for neural
developmentand maturationand functionofthe
CNS
• Decreasedthyroidhormone concentrationsmaylead
to alterations incognitivefunction
–Patients with hypothyroidism may develop
impairmentof attention,slowed motorfunction,
and poormemory
–Thyroid-replacement therapy may improve
cognitivefunction when hypothyroidism is
present
70. 6.Actionon BoneGrowth
– T3also may participatein osteoblast
differentiation and proliferation, and
chondrocyte maturation leading to
boneossification
71. 7.ActiononfemaleReproductiveSystem
• Normal thyroid hormone functionis
important for reproductivefunction
– Hypothyroidism may beassociated with
menstrual disorders, infertility, risk of
miscarriage,and other complications of
pregnancy
72. 8.ACTION ON GASTROINTESTINAL TRACT
• Generally, thyroxine increases the appetite and
food intake.
• It also increases the secretions and movements
of GI tract.
• So, hypersecretion of thyroxine causes
diarrhoea and the lack of thyroxine causes
constipation.
74. APPLIEDANATOMY
• Presenceof thyroidae imaA-chanceof profusebleeding
procedures in neckbelow
isthmus
• Thyroglossal cysts– Remnants of thyroglossalducts
at any point in the way of
descent,(midline nearhyoid)
• Pyramidallobe andpresenceof levator glandulae
thyroidae