Respiratory System Anatomy PDF

L24- RESPIRATORY SYSTEM - ANATOMY OF RESPIRATORY TRACT Dr.Pugazhandhi Bakthavatchalam Assistant Professor of Anatomy and Physiology, AUACAS, American University of Antigua LEARNING OUTCOMES Introduction and functions of the respiratory tract Structural and f...

L24- RESPIRATORY SYSTEM - ANATOMY OF RESPIRATORY TRACT Dr.Pugazhandhi Bakthavatchalam Assistant Professor of Anatomy and Physiology, AUACAS, American University of Antigua LEARNING OUTCOMES Introduction and functions of the respiratory tract Structural and functional divisions Innervation of the respiratory tract Structure and functions of the nose, pharynx, larynx, trachea and its divisions. PARTS OF UPPER REPIRATORY TRACT  NOSE- PARTS 1. External nose 2. Nasal cavity. EXTERNAL NOSE: Shape-Pyramidal Parts-Apex(tip) Root Dorsum Nostrils(Nares): Pair of piriform aperture. Medially-nasal septum Laterally-Ala of nose  BLOOD SUPLY AND INNERVATION Arteries:- Dorsal nasal branch ( ophthalmic) Infraorbital (maxillary) Alar and Septal (facial) Ext. Nasal Innervation:- Infraorbital sensory: External nasal and Alar , Septal Infratrochlear (opthalmic) Infraorbital (maxillary) Motor: Facial nerve branches.  NASAL CAVITY Divided into 2 halves by median nasal septum. Vestibule Asymmetrical. Nasal septum Extension: Nostrils Choanae Nostrils to choanae Vestibule: Close to nostrils Lined by skin(hairs& sebaceous gland) Nasal cavity: extent, division External nares Nasal septum External nares Posterior nasal aperture Subdivided into 2 halves Each half has a Roof Roof Floor Medial wall Medial Wall Lateral wall Each half measures about : Lateral Wall 5cm in height 5-7cm in length 1.5cm width near the floor Floor 1-2mm near the roof Nasal cavity: dimensions 5cm 1.5cm 5-7cm Nasal cavity: roof roof Ethmoid : cribriform plate  7cm long  2mm wide  Slopes downwards both in front and behind  Middle horizontal part -cribriform plate of ethmoid.  Anterior slope- nasal part of frontal bone, nasal bone & nasal cartilages.  Posterior slope- inferior surface of body of sphenoid. Floor  5cm long  1.5cm wide  Formed by palatine process of maxilla & horizontal plate of palatine bone  Concave from side to side.  Nasal septum (MEDIAL WALL)  Is the median osseocartilaginous partition between the 2 halves of the nasal cavity.  On each side covered by mucous membrane and forms the medial wall of both the Nasal septum nasal cavities.  Contains bony part and cartilaginous parts. Nasal Septum: Formation: Bony perpendicular plate of ethmoid, vomer  Nasal septum: Formation: cartilaginous Septal cartilage Inferior nasal cartilage  Nasal septum: Formation: cuticular Fibro-fatty tissue+skin columella Vomero-nasal organ of Jacobson Nasal septum: arterial supply  Venous Drainage Accompany- olfactory nerves into inferior cerebral veins Antero- Superior Superior ophthalmic vein Mobile part of the septum Facial vein to IJV (Dangerous area of face) Postero- inferior Pterygoid venous plexus Nasal septum: venous drainage Kiesselbach’s plexus Facial vein sphenopalatine vein pterygoid venous plexus  NERVE SUPPLY Ant. Ethmoidal N (ophthalmic) Olfactory zone Long Sphenopalatine, Short Sphenopalatine and Greater palatine N. ( Pterygo palatine ganglion & External Ant. Maxillary N) nasal nerve Superior alveolar nerve (Maxillary)  NASAL SEPTUM: nerve supply Special sensory General sensory  Lateral wall can be subdivided into 3 parts  A small depressed area in the anterior part called the vestibule.  Vestibule lined by modified skin containing short, stiff, curved hairs called Vibrissae and contain sweat and sebaceous gland.  Middle part is known as the atrium of middle meatus.  Posterior part contains the concha.  Spaces separating the concha are called Meatuses. LATERAL WALL OF NOSE: parts concha meatus Agger nasi: mucous ridge Atrium Of middle meatus Limen nasi: mucocutaneous ridge vestibule CONCHAE AND MEATUSES  NASAL CONCHAE (Turbinate bones) INFERRIOR CONCHA Separate bone. Extends horizontally backwards and ends 1.25cm in front of pharyngeal opening of auditory tube. Anteriorly continuous as Inf.concha Inf.concha Vestibule. Space under cover- Inferior meatus. Auditory tube Naso lacrimal Termination of naso lacrimal Inf.Meatus Inf.Meatus duct. duct.  MIDDLE CONCHA Middle meatus Bulla ethamoidalis- a bony bulging Middle ethamoidal air sinuses Opens into the meatus or above the bulla. Hiatus semilunaris Cresentric space below the bulla Maxillary sinus opens into posterior part of Hiatus semilunaris. Ethmoidal infundibulum A short passage at anterior end of the hiatus. Anterior ethmoidal and frontal sinus opens into it.  SUPERIOR CONCHA Shortest Superior meatus- Posterior ethamoidal sinus opens. Supreme meatus-b/w superior concha & roof of nasal cavity. Sphenoethamoidal recess-depression above &behind the superior concha. Sphenoidal air sinuses opens.  Nasal Passage Structure that open into the nasal meatus Inferior meatus Nasolacrimal duct Middle meatus Frontal sinus Maxillary sinus Anterior ethmoidal cells Middle ethmoidal cells Superior meatus Posterior ethmoidal cells Sphenoethmoidal Recess Sphenoidal sinus 30-Sep-24 28  LATERAL WALL OF NOSE: arterial supply Anterior ethmoidal Posterior ethmoidal sphenopalatine Facial Facial Greater palatine Greater palatine LATERAL WALL OF NOSE: nerve supply Anterior ethmoidal: Posterior superior lateral nasal ophthalmic Pterygopalatine ganglion (maxillary nerve) Anterior superior alveolar: Anterior palatine Pterygopalatine ganglion maxillary (maxillary nerve) LATERAL WALL OF NOSE: nerve supply Special sensory: olfactory nerve APPLIED ANATOMY: Spread of Infection Middle cranial fossa: Cribriform plate Lacrimal apparatus Nasolacrimal duct  APPLIED ANATOMY Septal deviation of septum any side causes congestion, obstruction corrected by sub mucosal resection of the nasal septum. Epistaxis-bleeding from nose. Dangerous area of the nose infection spread along the olfactory nerves to the cranial cavity. A broken nose, also called a nasal fracture or nose fracture, is a break or crack in the bone or cartilage of your nose. These breaks typically occur over the bridge of the nose or in the septum, which is the area that divides your nostrils. APPLIED ANATOMY DNS NASAL POLYP  LITTLE’S AREA Kiesselbach's plexus: - which lies in Kiesselbach's area, Kiesselbach's triangle, or Little's area, - It is a region in the anteroinferior part of the nasal septum where four arteries anastomose to form a vascular plexus. Importance: It is a common site of bleeding from nose (Epistaxis). 30-Sep-24 35 APPLIED ANATOMY: Allergic Rhinitis Hypertrophy of mucosa over inferior nasal concha  PHARYNX The pharynx is a 12–14 cm long. Musculomembranous tube shaped like an inverted cone. It extends from the cranial base to the lower border of the cricoid cartilage (the level of the sixth cervical vertebra), where it becomes continuous with the esophagus. The pharynx lies behind, and communicates with, the nasal, oral and laryngeal cavities via the nasopharynx, oropharynx and laryngopharynx, respectively. Divisible into nasopharynx, oropharynx,& laryngopharynx. Communication between oral cavity & pharynx is oropharyngeal isthmus 30-Sep-24 37 Features on nasopharynx: Opening of the auditory tube Tubal elevation Salpingopharyngeal & salpingopalatine fold Tubal tonsil & Pharyngeal tonsil (adenoids) Communication between naso & oropharynx is pharyngeal isthmus Features on oropharynx: Lies in front of C2 & upper part of C3 vertebra Palatopharyngeal folds/arches Palatine tonsil & tonsillar sinus 30-Sep-24 38 30-Sep-24 39 Features on laryngopharynx: Lies in front of C3-C6 vertebra Upper part formed by inlet of larynx below and posterior surfaces by arytenoid & cricoid cartilages. Wall of pharynx: Formed by skeletal muscles & fascia Buccopharyngeal fascia coats outside of muscle wall Pharyngobasilar fascia lines inside of the muscle wall 30-Sep-24 40 Constrictors of pharynx: Superior middle & inferior constrictors All originate posterior to nasal, oral & laryngeal cavities Fibers pass to posterior & lateral walls of pharynx meeting to form midline raphe. Longitudinal muscles of pharynx: Stylopharyngeus, palatopharyngeus & salpingopharyngeus. Nerve supply of muscles of pharynx: All constrictors & salpingopharyngeus by pharyngeal branch of vagus Stylopharyngeus by glossopharyngeal Palatopharyngeus by cranial part of accessory 30-Sep-24 41 Blood vessels & lymphatics of pharynx: Ascending pharyngeal, lingual, facial, maxillary arteries Venous plexus surrounding pharynx drains into internal jugular & facial veins Lymph vessels drain into deep cervical lymph nodes. Nerve supply of pharynx: Pharyngeal plexus formed by branches of glossopharyngeal, vagus,& cranial accessory 30-Sep-24 42  KILLIAN’S DEHISCENCE Killian's dehiscence (also known as Killian's triangle) is a triangular area in the wall of the pharynx between the thyropharyngeal and cricopharyngeus of the inferior constrictor of the pharynx. It represents a potentially weak spot where a pharyngoesophageal diverticulum (Zenker's diverticulum) is more likely to occur. 30-Sep-24 43  PARANASAL AIR SINUS Air filled spaces in bones that surround the nasal cavity. Named according to the bones in which they are located. There are four groups of sinuses: 1. Maxillary sinuses (Antrum of Highmore) 2. Ethmoid sinuses 3. Frontal sinus 4. Sphenoid sinus 30-Sep-24 44  PARANASAL AIR SINUS The paranasal sinuses are cavities found in the interior of the maxilla, frontal, sphenoid, and ethmoid bones. They are lined with mucoperiosteum and filled with air. They communicate with the nasal cavity through relatively small apertures. Lined by pseudostratified ciliated columnar epithelium. Maxillary sinuses - Aerated at birth Frontal /sphenoidal sinuses develop at :Age 6-7years Ethmoid - Develop during puberty and develop slowly until approximately 17- 18 years of age. 30-Sep-24 45  PARANASAL SINUS Sphenoid bone Ethmoid Bone Inferior Nasal Concha Vomer Palatine 30-Sep-24 46 PARANASAL AIR SINUS Perpendicular plate Ethmoidal sinuses Crista galli Cribriform foramina Orbital plate In cribriform plate 30-Sep-24 47  FUNCTIONS OF PARANASAL AIR SINUS Decrease skull bone weight Warm, moisten and filter incoming air Serve as a resonating chamber for voice Act as shock absorbers in trauma (like air bags in a car) Possibly help control Immune system When the apertures of the sinuses are blocked or they become filled with fluid, the quality of the voice is markedly changed. 30-Sep-24 48 APPLIED ANATOMY OF PARANASAL AIR SINUS Sinusitis- is an inflammation or swelling of the tissue lining the sinus. Healthy sinus are filled with air. But when they become blocked and filled with fluid germ can grow causes infection. There are many varieties of sinusitis-acute, subacute, chronic and recurrent. Common cold, allergic rhinitis, nasal polyp and deviated nasal septum can causes sinusitis also. 30-Sep-24 49 TRACHEA AND BRONCHIAL TREE  REFERENCES Drake R.L., Gray’s Anatomy for Students, 2nd Edition, 2009, Churchill Livingstone Moore, Clinically Oriented Anatomy, 6th Edition, 2009, Lippincott Williams & Wilkins Standring, Gray’s Anatomy: The Anatomical Basis of Clinical Practice, 40thEdition, 2008 Johannes W Rohen, Color Atlas of Anatomy: A photographic study of the human body, 7th Edition, Lippincott Williams & Wilkins Kenneth S Saladin, Human Anatomy, 2nd Edition, 2008, McGraw-Hill Companies 30-Sep-24 51