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1 Chapter 1 : Human Anatomy: Nose Worksheet theinnatdunvilla.com The human nose is the most protruding part of the face that bears the nostrils, and is the first organ of the respiratory theinnatdunvilla.com nose is also the principal organ in the olfactory system. The unitary division of the nasal topography permits minimal, but precise, cutting, and maximal corrective-tissue coverage, to produce a functional nose of proportionate size, contour, and appearance for the patient. The principal arterial blood-vessel supply to the nose is two-fold: The external nose is supplied with blood by the facial artery, which becomes the angular artery that courses over the superomedial aspect of the nose. Internally, the lateral nasal wall is supplied with blood by the sphenopalatine artery from behind and below and by the anterior ethmoid artery and the posterior ethmoid artery from above and behind. The nasal septum also is supplied with blood by the sphenopalatine artery, and by the anterior and posterior ethmoid arteries, with the additional circulatory contributions of the superior labial artery and of the greater palatine artery. These three 3 vascular supplies to the internal nose converge in the Kiesselbach plexus the Little area, which is a region in the anteroinferior-third of the nasal septum, in front and below. Furthermore, the nasal vein vascularisation of the nose generally follows the arterial pattern of nasal vascularisation. The nasal veins are biologically significant, because they have no vessel-valves, and because of their direct, circulatory communication to the sinus caverns, which makes possible the potential intracranial spreading of a bacterial infection of the nose. Hence, because of such an abundant nasal blood supply, tobacco smoking does therapeutically compromise post-operative healing. Lymphatic drainage The pertinent nasal lymphatic system arises from the superficial mucosa, and drains posteriorly to the retropharyngeal nodes in back, and anteriorly in front, either to the upper deep cervical nodes in the neck, or to the submandibular glands in the lower jaw, or into both the nodes and the glands of the neck and the jaw. Innervation Cranial nerve V, the trigeminal nerve nervus trigeminis gives sensation to the nose, the face, and the upper jaw maxilla. The sensations registered by the human nose derive from the first two 2 branches of cranial nerve V, the trigeminal nerve nervus trigeminis. The nerve listings indicate the respective innervation sensory distribution of the trigeminal nerve branches within the nose, the face, and the upper jaw maxilla. Cranial nerve VII nervus facialis is the facial nerve that gives motor innervation to the muscles of the face, including those which move the nose. The indicated nerve serves the named anatomic facial and nasal regions Ophthalmic division innervation Lacrimal nerve â conveys sensation to the skin areas of the lateral orbital eye socket region, except for the lacrimal gland. Frontal nerve â conveys sensation to the skin areas of the forehead and the scalp. Supraorbital nerve â conveys sensation to the skin areas of the eyelids, the forehead, and the scalp. Supratrochlear nerve â conveys sensation to the medial region of the eyelid skin area, and the medial region of the forehead skin. Nasociliary nerve â conveys sensation to the skin area of the nose, and the mucous membrane of the anterior front nasal cavity. Anterior ethmoid nerve â conveys sensation in the anterior front half of the nasal cavity: Posterior ethmoid nerve â serves the superior upper half of the nasal cavity, the sphenoids, and the ethmoids. Intratrochlear nerve â conveys sensation to the medial region of the eyelids, the palpebral conjunctiva, the nasion nasolabial junction, and the bony dorsum. The maxillary division innervation Maxillary nerve â conveys sensation to the upper jaw and the face. Infraorbital nerve â conveys sensation to the area from below the eye socket to the external nares nostrils. Zygomatic nerve â through the zygomatic bone and the zygomatic arch, conveys sensation to the cheekbone areas. Superior posterior dental nerve â sensation in the teeth and the gums. Superior anterior dental nerve â mediates the sneeze reflex. Sphenopalatine nerve â divides into the lateral branch and the septal branch, and conveys sensation from the rear and the central regions of the nasal cavity. The shell-form turbinates conchae nasales The septum nasi bones and cartilages The supply of parasympathetic nerves to the face and the upper jaw maxilla derives from the greater superficial petrosal GSP branch of cranial nerve VII, the facial nerve. The GSP nerve joins the deep petrosal nerve of the sympathetic nervous system, derived from the carotid plexus, to form the vidian nerve in the vidian canal that traverses the pterygopalatine ganglion an autonomic ganglion of the maxillary nerve, wherein only the parasympathetic nerves form synapses, which serve the lacrimal gland and the glands Page 1

2 of the nose and of the palate, via the upper jaw maxillary division of cranial nerve V, the trigeminal nerve. Internal nasal anatomy In the midline of the nose, the septum is a composite osseo-cartilaginous structure that divides the nose into two 2 similar halves. The lateral nasal wall and the paranasal sinuses, the superior concha, the middle concha, and the inferior concha, form the corresponding passages, the superior meatus, the middle meatus, and the inferior meatus, on the lateral nasal wall. The superior meatus is the drainage area for the posterior ethmoid bone cells and the sphenoid sinus; the middle meatus provides drainage for the anterior ethmoid sinuses and for the maxillary and frontal sinuses; and the inferior meatus provides drainage for the nasolacrimal duct. The internal nasal valve comprises the area bounded by the upper lateral-cartilage, the septum, the nasal floor, and the anterior head of the inferior turbinate. In the narrow leptorrhine nose, this is the narrowest portion of the nasal airway. Generally, this area requires an angle greater than 15 degrees for unobstructed breathing; for the correction of such narrowness, the width of the nasal valve can be increased with spreader grafts and flaring sutures. Development The embryonic human head, c. Two symmetrical nasal placodes the future olfactory epithelium develop inferiorly, which the nasal pits then divide into the medial and the lateral nasal processes the future upper lip and nose. The medial processes then form the septum, the philtrum, and the premaxilla of the nose; the lateral processes form the sides of the nose; and the mouth forms from the stomodeum the anterior ectodermal portion of the alimentary tract, which is inferior to the nasal complex. A nasobuccal membrane separates the mouth from the nose; respectively, the inferior oral cavity the mouth and the superior nasal cavity the nose. As the olfactory pits deepen, said development forms the choanae, the two openings that connect the nasal cavity and the nasopharynx upper part of the pharynx that is continuous with the nasal passages. Initially, primitive-form choanae develop, which then further develop into the secondary, permanent choanae. At ten 10 weeks of gestation, the cells differentiate into muscle, cartilage, and bone. If this important, early facial embryogenesis fails, it might result in anomalies such as choanal atresia absent or closed passage, medial nasal clefts fissures, or lateral nasal clefts, nasal aplasia faulty or incomplete development, and polyrrhinia double nose. Page 2

3 Chapter 2 : Anatomy of the Human Nose The nose is the body's primary organ of smell and also functions as part of the body's respiratory system. Air comes into the body through the nose. As it passes over the specialized cells of the. The nasal cavity lies between the base of the brain skull base and above the oral cavity and palate below. These paired sinuses are the maxillary lying in the cheek bones, frontal lying between the eyebrows, ethmoid between the eyes and the sphenoid sinuses between the center of the skull base and the nose. The paranasal sinuses drain into the nose, and their detailed anatomy is discussed in another Patient Education section. Smell is perceived through part of the roof of the nasal cavity olfactory cleft that is just next to the part of the brain responsible for smell olfactory bulb and fossa. These nerves supply the top parts pf the nasal septum, middle and inferior turbinates and carry smell sensations to the brain. In the nasal cavity, physical obstruction and injury, or inflammation to the olfactory cleft by tumors, polyps etc. The nasal septum is made up of cartilage quadrangular cartilage towards the front of the nose, and bone towards the back. Parts of four different bones make up the bony septum: The nasal septum is often not located in the midline, but pushed over to the right or left side in various parts. These deflections usually occur where the various parts of the nasal septum join together, due to overgrowth of one or more components. Sometimes, trauma to the nose can also create deflections and fractures. When this deviation is large or severe it can result in narrowing of one or both sides of the nasal cavity. In the front, the left and right sides of the nasal cavities form the right and left nares. The nasopharynx is the upper part of the throat pharynx, which lies below the skull base and opens into the oropharynx, the part of the throat that lies behind the mouth. When we breathe in, air travels through the nostril, through the right and left nasal passages, through the choana into the nasopharynx, then the oropharynx, and then through the voice box larynx into the lungs. The nasopharynx contains a collection of lymphoid tissue towards the midline, called the adenoids. Into each side of the nasopharynx open the eustachian tubes. The eustachian tubes connect the nasopharynx to the middle ear the part of the ear cavity behind the ear drums. The eustachian tubes help air to pass from the ear to the nasopharynx and vice versa and thus help fill the middle ear with air and equalize air pressure with the atmosphere. This function is very important for hearing normally. When the adenoids are enlarged or infected, eustachian tube, and thus ear function can be affected, leading to problems with fluid in the ear, or ear pain and pressure. Enlarged adenoids can also block the choana and affect breathing through the nasal passageways, leading to mouth-breathing and snoring. The nasal cavity is bounded in by bony sidewalls lateral nasal walls. Attached to these sidewalls are three structures called turbinates. The turbinates are fingerlike projections made up of a bony core and outer soft tissue. They are covered with a lining mucosa which is continuous with the lining of the rest of the nasal cavity. The turbinates serve to increase the mucosal surface area of the nasal cavity, and also direct smooth nasal airflow towards the lungs. Between each turbinate and nasal sidewall lies a space termed a meatus. These spaces are named according to the turbinate above them. This capacity of the inferior turbinate comes from soft tissue below the lining. This tissue is extremely rich in blood vessels and glands, and helps the nasal air-conditioning function. The inferior turbinate is the largest of the three paired turbinates, and runs along the entire length of the lateral nasal wall, adjacent to the nasal floor. Sometimes, the inferior turbinate can get enlarged due to allergy or irritation, and can cause nasal blockage and a runny nose. The tear duct nasolacrimal duct, which drains tears from the eye, drains beneath the inferior turbinate into the inferior meatus. The middle turbinate lies above the inferior turbinate and is a very important structure with a complex, boomerang shape. The front part of the middle turbinate is vertical, attaching to the skull base. The back of the middle turbinate is horizontal, and attaches to the nasal sidewall just above the inferior turbinate. The middle part of the middle turbinate is oblique, connecting the vertical and horizontal parts, and is thus connected both the skull base in the front and the nasal sidewall in the back. The frontal sinus and anterior ethmoid sinus cells drain beneath the middle turbinate into the middle meatus. The superior turbinate is the smallest of the turbinates. It resides just above and behind the middle turbinate. The sphenoid sinus and posterior ethmoid sinus cells drain into an area between the nasal septum and superior turbinate called the Page 3

4 sphenoethmoid recess. The nose is also the air-conditioner of our breathing passageways: This mucosal surface has microscopic hair like structures cilia and many mucus producing glands. The moist, mucus-covered surface mucus blanket of the nasal cavity traps harmful particles such as allergens or bacteria. This mucus blanket is continuously propelled backwards by millions of cilia that all beat to the same rhythm such that the trapped particles are directed to the back of the nasal cavity. The sidewall of the nose also contains structures that are rich in blood vessels and glands called turbinates; these humidify and warm or cool the inhaled air. The nose thus cycles function to each side every 90 minutes to 4 hours. You can read more in a separate Patient Education topic on Nasal Physiology. This area can often be cauterized in the office to stop nasal bleeding. The anterior and posterior ethmoid arteries, both branches of the internal carotid artery system supply the upper nasal septum and nasal sidewalls. The superior labial branch of the facial artery supplies the front part of the nose. The sphenopalatine artery, a branch of the external carotid system supplies most of the back of the nasal cavity. It enters the nasal cavity through an opening located along the nasal sidewall called the sphenopalatine foramen. When nasal bleeding is more from the back part posterior epistaxis, this artery is often the culprit. When recurrent posterior epistaxis becomes a problem, the sphenopalatine artery may need to be tied or embolized. This lattice of veins is a common source of nasal bleeding epistaxis due to trauma and dry air exposure, and may require medical attention in many cases. Nerve Supply Sensation to the nose is provided to the nasal cavity primarily via branches of the trigeminal nerve. The ophthalmic division V1 of the trigeminal nerve gives off the anterior and posterior ethmoidal nerves, which supply sensation to the top half of the nasal cavity and septum. The maxillary division V2 of the trigeminal nerve exits the skull base via an opening called the foramen rotundum and ultimately divides into several smaller branches. The largest of these branches is the sphenopalatine nerve, which travels with the corresponding artery and supplies sensation to the lateral nasal wall and septum. Sensations of the nasal cavity can be disrupted by injury to the mid-face and palate due to trauma, tumors or surgery, resulting in numbness. The nose is also richly supplied by special nerves from the autonomic nervous system. In the nose, the autonomic nerves control the air-conditioning action, nasal resistance, mucus secretion and the function of the cilia and mucus blanket. This nerve ultimately becomes the vidian nerve, which sends parasympathetic nerve fibers along with branches of the sphenopalatine nerve Blood flow to the nasal cavity and nasal mucosa is controlled largely by sympathetic innervation, fibers of which also travel along with the sphenopalatine nerve. Changes in sympathetic stimulation result in a rhythmic swelling of nasal blood vessels and a corresponding increase in nasal airway resistance nasal cycle. The autonomic nerve systems can often be imbalanced during old age or due to allergies, inflammation, infection or medications. Normal nasal function can be disrupted, leading to nasal congestion and increased nasal secretions. Read about using endoscopes to examine the nasal cavity and learn more about sinus anatomy. Page 4

5 Chapter 3 : Anatomy of the human nose - Infogalactic: the planetary knowledge core human respiratory system: The nose The nose is the external protuberance of an internal space, the nasal cavity. It is subdivided into a left and right canal by a thin medial cartilaginous and bony wall, the nasal septum. Anatomy of the Nose Anatomy of the Nose The nose is a complex component of the facial anatomy that is comprised of numerous structures. Here we will go from top to bottom and describe each of the components. External Structure The surface of the human nose consists of a frontal portion comprised of the glabella, nasion, alar sidewalls and tip points; a basal portion made up of the columella, nostrils, soft tissues and infra tip lobule; and two other portions called the latter and oblique sections. Internal Structure Bone The bony portion of the nose only makes up the upper third of the nose bridge. Physically, it is responsible for the height of the nose. It provides the support for the upper portion of the nose. Nasal Cavity The entire nasal cavity is lined with a mucosal surface made up of epithelial cells and glands that produce mucus. This mucus keeps the inside of the nose moist, traps allergens and other particles and helps keep the air you breathe in humid. Millions of cilia continually move the mucus layer across the mucosal surface, pushing harmful particles out of the nose in the process. In this sense, the nose is an air filter that purifies air before it reaches the lungs. Frontal view, anatomy of the nose. At the very top of the nasal anatomy is the nasopharanx, which contains lymphoid tissue known as the adenoids. In addition to meeting with the nose, the nasopharanx is also connected to the ears via the Eustachian tubes. An area called the choana links the nasopharanx to the left and right portions of the nasal cavity, which is the space above the oral cavity and hard palate. Located below the skull base and intracranial compartment, it is divided by the septum. Septum The septum is comprised of bone in the back and cartilage in the middle and front portions. The bony part, which is immovable, is made of up the perpendicular maxilla bone, the vomer bone and the ethmoid bone. The septal cartilage, which is moveable, is surrounded by another section of cartilage called the lateral nasal cartilage. The lateral nasal walls, or sidewalls, each contain three finger-like structures called turbinates. These are made of bony core covered with soft tissue and mucosa. The turbinates regulate nasal airflow and provide mucosa surface area. The largest turbinate is called the inferior turbinate. It is located along the whole length of the nasal sidewall, next to the nasal floor. The middle turbinate is located next to the septum and extends into the central nasal cavity. It is attached to the sidewall at the back, right above the inferior turbinate. The smallest of the three turbinates is called the superior turbinate. It is located above and behind the middle turbinate and attaches to the skull base and nasal wall. Cartilage Below the septal cartilage is the greater alar cartilage, which forms the lateral and medial walls of the nostrils, and below this are four lesser alar cartilages. Together, the greater alar cartilage and the lesser alar cartilages give your tip and nostrils their shape. Determinants for the shape of the nose. Near the tip of the nose are the nostrils and the columella â the strip of skin between the nostrils. The portion of the nostrils that attach to the cheeks is called the alae. Your nose also has four types of muscles called elevators, depressors, compressors and dilators. They are connected by a structure called the nasal superficial masculoaponeurotic system. Figure 5 shows the basic components of the nose that are altered during rhinoplasty procedures. Bone â The bone cane be carefully and minimally shaved down to lower the height of the nasal bridge. Cartilage â The cartilage is the most altered part of the nose in rhinoplasties. To decrease the size of the nose in any specific area, cartilage can be strategically sutured without sacrificing the support structure. Nostrils â The nostrils can be made smaller by making an incision right along the alar base and bringing the width inwards. Skin â Thick nasal skin is reduced by thinning the fatty tissue underneath the skin. To learn more about the anatomy of the nose, contact my office today. Page 5

6 Chapter 4 : Anatomy of the Nose Becker Rhinoplasty New Jersey The Human Nose: Anatomy and Structure The structure of a human nose is composed of bones, cartilage, and fibrofatty tissues. And the external feature of a nose or the type of nose depends upon the bone and cartilage. Click on Image to Enlarge Introduction A part of the respiratory tract, the nose is the protruding part of the face that sits at the centre. It bears nostrils through which we breathe and smell fragrances. Nose gets its shape by the ethmoid bone and the nasal spectrum. On an average, males have larger nose than females. The external part of the nose has the roots that are between the eyes the dorsum that runs down the middle and the apex, which is the nose tip. There are two openings, called nostrils that help us in inhaling and exhaling air. The nasal spectrum, consisting of cartilage and bones, divides the nostrils. The nostrils are surrounded by parts known as alae. The bony part of the nose is formed by the bony nasal spectrum, nasal bones as well as parts of maxillae, palatine and frontal bones. The cartilaginous portion of the bones is formed by two lateral cartilages, two alar cartilages and a special cartilage. The Bone Anatomy The paired nasal bones attach to the frontal bones in the upper portion of the nose; connects to the lacrimal bones in the above and side portions and joins the ascending processes of the maxilla in below and sides. The bony nasal spectrum is made of the perpendicular plate of the ethmoid bone. The vomer bone is located below and at the back and is responsible for partially forming the choanal opening into the nasopharynx, which is the upper portion of the pharynx that is continuous with the nasal passage. The internal roof of the nose is formed by the horizontal and perforated cibriform plate through which the sensory filaments of the olfactory nerves pass. The nasal septum is made of quadrangular cartilage, vomer bone and few portions of the premaxilla and palatine bones. It extends from the nasal bones in the midline to the bony septum in the midline and then down along the bony floor. The Nasal Cavity The presence of nares serves as a gateway to the nasal cavities. It posteriorly opens into the nasopharynx through the choanae. The nasal cavity is lined with nasal mucosa, except the nasal vestibule which is lined with the skin. The mucosa over the superior one-third of the nasal cavity forms the olfactory area. In this, the olfactory epithelium contains receptors of the olfactory neurons which help in detecting smells. The olfactory tract also helps in transmitting sensory information. There are walls within the nasal cavity, which have the following features: The roof of the naval cavity wall is divided into three parts: Each of these parts corresponds to the underlying bone, of the same name. The floor includes the palatine process of the maxilla and the horizontal plate of the palatine bone. The medial wall is the nasal septum along with its surrounding bones. Each lateral nasal wall has three pairs of turbinates, consisting of small, thin and shell-form bones: The turbinates divide the nasal cavity into four passages that finally opens to the paranasal sinuses. The Paranasal Sinuses These are air-filled cavities that are present in the sphenoid, ethmoid, maxilla and frontal bones. They have a mucosal membrane lining and have minute openings into the nasal cavity. Found in the sphenoid bone, each of the sinuses open into the sphenoethmoid recess. There are three types of ethmoid sinuses, namely anterior, middle and posterior, all of which are located in the ethmoid bone between the nose and the eye. The anterior sinus opens into the nasal cavity by means of the infuldibulum. The middle sinus opens into the ethmoidal bulla. The posterior sinus opens into the superior meatus. This sinus is located in the maxilla body behind the cheek and above the premolar and molar teeth roots. Being a pyramid shape, it opens into the nasal cavity through the semilunar hiatus. The sinus is present in the frontal bone. Each of the sinuses is triangular in shape and runs above the medial end of the eyebrows and backwards to the orbit. Like the maxillary sinuses, they also open into the nasal cavity via semilunar hiatus. Nerve Supply, Blood Supply and Drainage The infratrochlear and the external nasal branches of the ophthalmic nerve as well as the infraorbital branch of the maxillary nerve are responsible for nerve supply to the external nose. Both of these nerves are a part of the trigeminal nerve CN V. The olfactory nerves pass through the cribiform plate of the ethmoid bone. The human nose being well vascularized with arteries and veins therefore gets sufficient blood supply. There is a two-fold principal of arterial blood-vessel supply to the nose: Branches of the ophthalmic and maxillary arteries supply blood to the external nose. The ala and the septum skin are supplied by the facial artery. The maxillary arteries bring blood to the walls of the nasal cavity and sinuses. Of all the arteries, the Page 6

7 sphenopalatine artery is most important since it anastomoses with the superior labial artery branch. Venous blood is returned from the nasal cavity by veins accompanying the arteries. Internally, the lateral nasal wall is supplied with blood by the sphenopalatine artery. Lymphatic Drainage The lymphatic system of the nasal cavity arises from the superficial mucosa and drains posteriorly to the retropharyngeal nodes at the back and anteriorly in front either to the upper deep cervical nodes in the neck or into the submandibular lymph nodes and vessels in the lower jaw. It can also drain into both the nodes and glands of the neck and the jaw. Page 7

8 Chapter 5 : Human nose - Wikipedia Information on the anatomy of the nose also can be found in the With regard to the human nasal cycle, Williams and Eccles proposed a model for the. Structure[ edit ] Several bones and nasal cartilages make up the bony-cartilaginous framework of the nose, and the internal structure. The nose is also made up of types of soft tissue such as skin, epithelia, mucous membrane, muscles, nerves, and blood, and in the skin there are sebaceous glands. Framework[ edit ] The nose has a framework made up of bone and cartilage. This structure provides strong protection for the internal structures of the nose, and the arrangement of the cartilages allows flexibility through muscle control to modify airflow. Bones Bones of the nose and septal cartilage The nasal part of the frontal bone ends in a serrated nasal notch that articulates at the front with the paired nasal bones, and at the sides with the small lacrimal bones and with the frontal process of each maxilla. The nasal bones in the upper part of the nose are joined together by the midline nasal intersuture. They join with the septal cartilage at a junction known as the rhinion. Above and to the back, the bony upper part of the nasal septum is made up of the perpendicular plate of the ethmoid bone, and the lower bony part is made up of the vomer bone that lies below. The floor of the nose is made up of the incisive bone and the palatine bone, and this makes up the roof of the mouth. The internal roof of the nasal cavity is composed of the horizontal, perforated cribriform plate of the ethmoid bone through which pass sensory fibers of the olfactory nerve CN1. Below and behind the cribriform plate, sloping down at an angle, is the face of the sphenoid bone. The two maxilla bones join at the base of the nose at the lower nasal midline between the nostrils, and at the top of the philtrum to form the anterior nasal spine. This thin projection of bone holds the cartilaginous center of the nose. The septal nasal cartilage, extends from the nasal bones in the midline, to the bony part of the septum in the midline, posteriorly. It then passes along the floor of the nasal cavity. The septum is quadrangular; the upper half is atttached to the two lateral nasal cartilages which are fused to the dorsal septum in the midline, and laterally attached, with loose ligaments, to the bony margin of the anterior nasal aperture, while the inferior ends of the lateral cartilages are free unattached ; the minor alar cartilages are adjacent to the lateral cartilages in the fibroareolar connective tissue. Beneath the lateral cartilages lay the major alar cartilages, which swing outwards, from medial attachments, to the caudal septum in the midline the medial crura to an intermediate crus shank area. Finally, the major alar cartilages flare outwards, above and to the side superolaterally, as the lateral crura; these cartilages are mobile, unlike the upper lateral cartilages. Furthermore, some persons present anatomical evidence of nasal scrollingâ i. External nose[ edit ] The nasal root is the top of the nose, above the bridge and below the glabella, forming an indentation known as the nasion at the frontonasal suture where the frontal bone meets the nasal bones. The nasal ridge dorsum nasi is the border between the root and the apex of the nose which in profile can be variously shaped. From the glabella to the bridge the skin is thick, fairly flexible, and mobile. It tapers to the bridge where it is thinnest and least flexible as it adheres to the bony framework. The rest of the skin of the lower nose is as thick as the top section and has more sebaceous glands. Internal nose[ edit ] The nasal cavity is the large internal space of the nose. The cavity is divided into two cavities fossae by the nasal septum, which separates the nostrils. The nasal vestibule is the frontmost part of the nasal cavity, and is enclosed by cartilages. On the lateral wall of each cavity are three shell-like bones called conchae, arranged as superior, middle, and inferior conchae. Below each concha is a corresponding superior, middle, and inferior meatus. The conchae are also known as turbinates. Sometimes when the superior concha is narrow, a fourth supreme nasal concha is present situated above and sharing the space with the superior concha. The turbulence created by the conchae and meatuses optimises the warming, moistening, and filtering of the mucosa. The choanae are also called the posterior nostrils. There is a nasal valve area in the nose that is responsibe for providing resistance to the flow of air. This enables increased warming and moistening of the air. Two valves are often referred to for this area, an internal nasal valve and an external nasal valve. The internal nasal valve is the narrowest part of the airway. Further into the nasal cavity this changes to columnar respiratory epithelium, a pseudo-stratified, ciliated tissue with mucus -secreting goblet cells, which maintains the nasal Page 8

9 moisture and protects the respiratory tract from infection and atmospheric particulates. The respiratory epithelium also covers the paranasal sinuses. The cilia in the sinuses beat towards the openings into the nasal cavity. Most of the ostia open into the middle meatus and the anterior ethmoid, that together are termed the osteomeatal complex. There are four interconnected groups connected by the superficial fascia that covers, invests and forms the terminations of the muscles. The elevator muscle group includes the procerus muscle that helps to flare the nostrils; and the levator labii superioris alaeque nasi muscle, which lifts the upper lip and the alae. The depressor muscle group includes the alar nasalis muscle and the depressor septi nasi muscle. The compressor muscle group includes the transverse nasalis muscle. The dilator muscle group includes the dilator naris muscle that expands the nostrils; it is in two parts: Blood supply and drainage[ edit ] The nose, in particular the nasal cavity, is well supplied with blood from branches of both the internal carotid artery, and the external carotid artery. Internal carotid The main branches from the interior carotid are the anterior ethmoidal artery, and the posterior ethmoidal artery that supplies the septum, and these derive from the ophthalmic artery. One of the terminal branches of the ophthalmic artery is the dorsal nasal artery which divides into two branches. One branch crosses the root of the nose and joins with the angular artery, and the other branch joins with the lateral nasal branch of facial artery which supplies the nasal ridge and alae. External carotid Branches from the external carotid artery are the sphenopalatine artery, the greater palatine artery, the superior labial artery, and the angular artery. The lateral walls of the nasal cavity and the septum are suppled by the sphenopalatine artery, and by the anterior and posterior ethmoid arteries. There is additional supply from the superior labial artery and the greater palatine artery. The nasal ridge is supplied by branches of the internal maxillary artery infraorbital and the ophthalmic arteries from the common carotid artery system. Drainage Veins of the nose include the angular vein that drains the side of the nose, receiving lateral nasal veins from the alae. The angular vein joins with the superior labial vein. Some small veins from the nasal ridge dorsum drain to the nasal arch of the frontal vein at the root of the nose. This plexus is made up of large thin-walled veins with little soft tissue such as muscle or fiber. The mucosa of the plexus is thin with very few structures. Nerve supply[ edit ] The trigeminal nerve CN5 gives sensation to the nose, the face, and the upper jaw maxilla. The facial nerve cranial nerve VII gives motor innervation to the muscles of the face, including those which move the nose. Ophthalmic innervation Nasociliary nerve â conveys sensation to the skin area of the nose, and the mucous membrane of the anterior front nasal cavity. Anterior ethmoid nerve â conveys sensation in the anterior front half of the nasal cavity: Posterior ethmoid nerve â serves the superior upper half of the nasal cavity, the sphenoids, and the ethmoids. Intratrochlear nerve â conveys sensation to the medial region of the eyelids, the palpebral conjunctiva, the nasion nasolabial junction, and the bony dorsum. Maxillary innervation Internal nasal branches of infraorbital nerve â conveys sensation to the septum. Zygomatic nerve â through the zygomatic bone and the zygomatic arch, conveys sensation to the cheekbone areas. Sphenopalatine nerve â divides into the lateral branch and the septal branch, and conveys sensation from the rear and the central regions of the nasal cavity. The supply of parasympathetic nerves to the face and the upper jaw maxilla derives from the greater superficial petrosal GSP branch of cranial nerve VII, the facial nerve. The GSP nerve joins the deep petrosal nerve of the sympathetic nervous system, derived from the carotid plexus, to form the vidian nerve in the vidian canal that traverses the pterygopalatine ganglion an autonomic ganglion of the maxillary nerve, wherein only the parasympathetic nerves form synapses, which serve the lacrimal gland and the glands of the nose and of the palate, via the upper jaw maxillary division of cranial nerve V, the trigeminal nerve. Development[ edit ] The developing head at about four weeks. At four weeks, gestational age, the neural crest cells the precursors of the nose begin their caudal migration from the posterior towards the midface. Two symmetrical nasal placodes the future olfactory epithelium develop inferiorly. In the sixth week they invaginate to form two nasal pits. The nasal pits then divide into the medial and the lateral nasal processes the future upper lip and nose. The medial processes then form the septum, the philtrum, and the premaxilla of the nose; the lateral processes form the sides of the nose; and the mouth forms from the stomodeum the anterior ectodermal portion of the alimentary tract, which is inferior to the nasal complex. A nasobuccal membrane separates the mouth from the nose; respectively, the inferior oral cavity the mouth and the superior nasal cavity the nose. As the nasal pits deepen, said development forms the choanae, Page 9

10 the two openings that connect the nasal cavity and the nasopharynx upper part of the pharynx that is continuous with the nasal passages. Initially, primitive-form choanae develop, which then further develop into the secondary, permanent choanae. At ten weeks, the cells differentiate into muscle, cartilage, and bone. Problems at this stage of development can cause birth defects such as choanal atresia absent or closed passage, facial clefts and nasal dysplasia faulty or incomplete development [14] or extremely rarely polyrrhinia the formation of a duplicate nose. The nose is responsible for warming and moistening the air and providing its passage to the rest of the respiratory tract. Another function is to filter the air by removing particulates. The three positioned nasal conchae in each cavity provide four grooves as air passages, along which the air is circulated and moved to the nasopharynx. Sneezing is an important reflex initiated by irritation of the nasal mucosa to expel unwanted particles through the mouth and nose. Photic sneezing is a reflex brought on by different stimuli such as bright lights. Olfaction[ edit ] The nose also plays the major part in the olfactory system. It contains an area of specialised cells, olfactory receptor neurons responsible for the sense of smell. Speech[ edit ] Normal speech is produced with pressure from the lungs. This can be modified using airflow through the nose in a process called nasalization. This involves the lowering of the soft palate to produce nasal vowels and consonants by allowing air to escape from both the nose and the mouth. Nasal airflow is also used to produce a variety of nasal clicks called click consonants. The nasal cavity is the third most effective vocal resonator. Rhinoplasty One of the most common medical conditions involving the nose are nosebleeds in medicine: Nasal congestion is a common symptom of infections or other inflammations of the nasal lining rhinitis, such as in allergic rhinitis or vasomotor rhinitis resulting from nasal spray abuse. Most of these conditions also cause anosmia, which is the medical term for a loss of smell. In children the nose is a common site of foreign bodies. Nasal flaring is a sign of respiratory distress that involves widening of the nostrils on inspiration. Because of the special nature of the blood supply to the human nose and surrounding area, it is possible for retrograde infections from the nasal area to spread to the brain. Page 10

11 Chapter 6 : DIAGRAM OF THE HUMAN NOSE The visible part of the human nose is the protruding part of the face that bears the theinnatdunvilla.com shape of the nose is determined by the ethmoid bone and the nasal septum, which consists mostly of cartilage and which separates the nostrils. Check new design of our homepage! Anatomy of the Nose: Human Nose Structure and Functions Explained The nose organ is responsible for sensing smell, filtering air, and breathing. Understanding the human nose anatomy helps in determining the distinctive appearance and confirming problems if any. Here, we will be discussing the nose structure in detail. Bodytomy Staff Last Updated: Jan 23, Nose is the most prominent feature located in the middle of the face of humans. An organ of the upper respiratory tract, it is actively involved in inhalation. The most important functions of nose are to filter the atmospheric air before passing it further into the respiratory system and to provide the sense of smell. At the time of breathing, air entering through the nostrils is led to the nasal cavity, which further passes to the pharynx, trachea, bronchi, and finally, to the lungs. Anatomy and Structure The structure of a human nose is composed of bones, cartilage, and fibrofatty tissues. And the external feature of a nose or the type of nose depends upon the bone and cartilage. According to the shapes and sizes of human nose, they can be classified into different types such as the Roman or aquiline, the Greek or straight, the Nubian, the hawk, the snub, and the turn up types. Human races can be identified by the type of nose; for example, the Europeans have long, narrow, large elevation height of the nose tip above the lip, and vertically set nostrils. Supporting structure of the upper part of nose is mostly made up of bones. The topmost portion near the eye sockets consists of two nasal bones, which is linked to the frontal bone of the forehead. These nasal bones are joined to form the nose bridge. On the sides, they are connected with the lateral process of the maxilla by a tough fibrous membrane. At the base, nasal bones are connected with septal and lateral nasal cartilage. The lower part of the nose is made up of cartilages. These cartilages give shape to the external feature of the nose. To speak in simple words, the nasal bone can be felt in between the eyelids, while the cartilage extends from the nose tip to the middle portion. Coming to the nasal septum, the nose bridge continues with the septal cartilage to form the septum. As we all know, the nasal septum separates the nostrils, which in turn, continue with the nasal cavity. Again, there are three horizontal outgrowths of bones, called turbinate or conchae that divide the nasal cavity into three groove-like air passages. Main purpose of conchae is to increase the surface area of the nasal cavity. The three turbinates are named as inferior, middlen and superior turbinates, according to their position and functions. On either side of the septal cartilage, there lies the lateral nasal cartilage. Just below the lateral nasal cartilages, the greater alar cartilage is present, which is a thin, flexible plate that forms the medial and lateral wall of the nostril. In addition to greater alar cartilages, there are three or four small cartilages that are called lesser alar cartilages. Both the greater and lesser alar cartilages give the overall shape of the nostrils. Hair are present inside the nostrils, which play a major role in filtration and humidification of atmospheric air as it passes them. Indirectly, nose hair serve as a defense mechanism against the harmful pathogens and solid particulate matter present in the air. Both the nostrils and nasal cavity are lined by mucous membrane and cilia. The membrane secretes a sticky substance called mucus. Together, this mucus and cilia filter the air and prevent entry of foreign particles such as microorganisms, dust, and particulate matter inside the respiratory system. The mucus also helps in moistening the air. Underneath the mucous membrane, there are blood capillaries that warm the air so that it matches the body temperature. You might have already heard about the sinuses and sinus infections. The bones of the face around the nose region contain the sinuses. Anatomically, sinuses are hollow air cavities that are lined by mucous membrane similar to the nasal cavity, and they are also known as paranasal sinuses. There are four subgroups of sinus, classified based on the bones to which the sinuses are present. They are frontal, maxillary, ethmoid, and sphenoid sinus. Among these four sinuses, ethmoid sinus is located around the area of nose bridge. An abnormality in any of these paranasal sinuses cause sinus problems. To sum up, nose is responsible for respiration and olfactory perception. At present, nose surgery or rhinoplasty is performed to improve the appearance, and also, to correct medical problems related to the bone, which Page 11

12 impair the respiration process. People with deviated septum frequently participate the procedure. This septum condition may be present at birth or may be resulted due to an accident. Giving satisfactory results in terms of improved appearance and function, nose surgery has become an important procedure in the field of cosmetic or plastic surgery. Page 12

13 Chapter 7 : Anatomy of the Nose Internal and External Nasal Structure Nose gets its shape by the ethmoid bone and the nasal spectrum. On an average, males have larger nose than females. The external part of the nose has the roots that are between the eyes the dorsum that runs down the middle and the apex, which is the nose tip. A human nose is the part of the respiratory region that is placed in the centre most front of a human face. To know the anatomy of the nose, its functions must be understood first. The basic function of the nose includes to breathe in and out air, and to smell. The nose is the only means of getting warm humidified air into the lungs. It is the only organ for filtering out molecules in inspired air, and it also plays a part to provide first-line immunologic safeguard by channelizing the contact between inspired air and mucous-coated membranes that consists of immunoglobulin A IgA. Inspired air is fetched high into the nasal cavity to bring in contact with the olfactory nerves, thus giving the sense of smell, which is closely related with the taste sensation. Debiliated functioning of any of these systems can prompt symptoms of nasal impairment eg, sinus infections, congestion, postnasal drainage, headaches, facial pressure. Endoscopic view from olfactory nerves of right nasal passage. Thereby, alterations in the physiology of the nose and paranasal sinuses can and will have an effect on the lower airways and vice versa. The nose is an intricate integrant of the facial anatomy that is made up of myriad of structures. Here we will go from top to bottom and explain each of the components for a thorough awareness of the composition of a human nose. Internal Structure of Nose Bone The bony part of the nose only constitutes to the upper 3rd of the nose bridge. Tangibly, it is held accountable for the length of the nose. Nasal Cavity The whole of the nasal cavity is fringed with a surface composed up of glands and epithelial cells that forms mucus. This mucus helps to keep the inside of the nose damp, traps allergens and other tiny bits or particles and helps to keep the air moist that you breathe in. Heaps of cilia constantly keep moving the mucus layer across the mucosal surface, sweeping toxic particles out of the nose in the process. In this manner, the nose is an air purifier that cleanses air before it reaches the lungs. At the peak of the nasal anatomy is the nasopharanx, which accomodates lymphoid tissue called the adenoids. Situated under the skull base and intracranial compartment, it is divided by the septum. Septum The septum consists of bone in the back and cartilage in the front and middle portions. The bony part, which remains fixed, is composed of the perpendicular maxilla bone, the ethmoid bone and the vomer bone. The septal cartilage, which is moveable, is bordered by another portion of cartilage known as the lateral nasal cartilage. The lateral nasal walls, or sidewalls, each comprises of 3 finger-like structures called turbinates, which are made of bony core covered with mucosa and soft tissue. The turbinates govern nasal airflow and render mucosa surface area. The biggest turbinate portion is known as the inferior turbinate. It is situated along the complete length of the nasal sidewall, subsequent to the nasal floor. The middle turbinate is situated next to the septum and stretches into the central nasal cavity. It is connected to the sidewall at the back, right above the inferior turbinate. The smallest of the 3 turbinates is known as the superior turbinate. It is situated above and at the back of the middle turbinate and links to the skull base and nasal wall. Cartilage Right below the septal cartilage is the larger alar cartilage, which creates the medial and lateral walls of the nostrils, and below this are 4 lesser alar cartilages. Near the tip of the nose are the nostrils and the columella â the strip of skin between the nostrils. The portion of the nostrils that attach to the cheeks is called the alae. Your nose also has 4 kinds of muscles known as elevators, compressors, depressors, and dilators. They are linked by a framework known as the nasal superficial masculoaponeurotic system. External Structure of Nose The facet of the human nose comprises of a frontal section consisting of the glabellas, alar sidewalls, nasion, and tip points; a basal section comprises of the nostrils, columella, infra tip lobule, and soft tissues; and two other section termed as oblique and latter sections. The external area of the nose involves the dorsum that travels down the middle and the apex at the tip of the nose and the root between the eyes. They are fractioned by the nasal septum dividing wall of bone and cartilage, and the parts that encompass the nostrils are known as the alae ala singular. The nose has a bony part that is produced by the bony nasal septum, parts of the maxillae, palatine, the nasal bones, and frontal bones. The cartilaginous part of the nose is created by 2 alar cartilages, 2 lateral cartilages, and a septal Page 13

14 cartilage. The paranasal sinuses The paranasal sinuses are air-packed cavities in the frontal, maxilla, ethmoid, and sphenoid bones. They are bordered with a mucosal membrane and have little openings into the nasal cavity: This sinus is positioned in the body of the maxilla at the back of the cheek area right above the roots of the molar and the premolar teeth. It is formed like a pyramid. It opens into the nasal cavity by way of the semilunar hiatus. Constructed within the frontal bone, each of these sinuses is triangular in shape and goes atop of the medial end of the eyebrow and retrogrades to the orbit. They open into the nasal cavity by way of the semilunar hiatus. The anterior, posterior and middle ethmoid sinuses are positioned in the ethmoid bone in between the nose and the eye. The anterior sinus opens into the nasal cavity via the infundibulum, the posterior sinus opens into nasal cavity via the superior meatus, and the middle sinus opens into the ethmoidal bulla. These sinuses are present in the sphenoid bone, with each opening into the sphenoethmoid recess. Nerves, blood vessels, and lymphatics of the nose Nerve supply to the external nose is rendered by the external and the infratrochlear nasal branches of the infraorbital branch of the maxillary nerve and the ophthalmic nerv, both of which are constituent of the trigeminal nerve CN V. The olfactory nerves CN I go through the cribiform plate of the ethmoid bone. Basic sensory innervations of the paranasal sinuses and nasal cavity are from the maxillary nerve CN V2 and the ophthalmic nerve CN V1. Blood is transported to the external part of the nose by divisions of the maxillary arteries and ophthalmic. The skin of the septum and ala are transported by the facial artery. Blood is obtained in the sinuses and nasal cavity walls by divisions of the maxillary artery. The basic components of the nose that are changed during rhinoplasty procedures are as follows: Bone â The bone can be cautiously and mildly shaved down to lessen the height of the nasal bridge. Cartilage â In rhinoplasties, this is the most altered part of the nose. To lower down the size of the nose in any particular area, cartilage can be tactfully sutured without sacrificing the support structure. Nostrils â The nostrils can be made to contract in size by making an incision right along the alar base and getting the width inwards. Skin â Thick nasal skin is decreased by thinning the fatty tissue below the skin. Tests of nasal physiology include studies of airflow, olfaction and ciliary function. Rhinomanometry is conducted to measure nasal airflow and total nasal area at the time of exclusive nasal breathing. Differential pressure quantifications are attained by locating a nasal catheter into the nasopharynx. Acoustic rhinometry is a modern method for assessing the cross-sectional area of the nose and the volume of the nasal cavity by evaluation of reflected sound during a short stoppage of nasal breathing. This method has been approved and is also helpful for documenting alterations in nasal patency caused by surgical or pharmaceutics interventions. The technique is fast and minimally invasive Radiologic imaging with MRI or CT also can evaluate the cross-sectional area of nasal passages The saccharin test assesses ciliary function by gauging the time it takes for a drop of saccharin to be tasted behind the throat when put on to the anterior tip of the inferior turbinate. Page 14