Nose, Nasal cavity, Paranasal Sinuses & Pharynx Respiratory block-Anatomy-Lecture 2 Editing file Color guide : Only in boys slides in Green Only in girls slides in Purple Objectives important in Red Doctor note in Blue Extra information in Grey At the end of the lecture, the students should be able to: ● Describe the boundaries of the nasal cavity. ● Describe the nasal conchae and meati. ● Demonstrate the openings in each meatus. ● Describe the paranasal sinuses and their functions. ● Describe the pharynx and its parts. Nose & Nasal cavity 3 Nose Nasal cavity nares/nostrils The external (anterior ) nares - Extends from the external (anterior) nares to the posterior nares or nostrils, lead to the nasal (choanae). cavity. - Divided into right & left halves by the nasal septum. - Formed above by: Bony skeleton. - Each half has a: ▪ Roof - Formed below by: ▪ Lateral wall plates of hyaline cartilage. ▪ Medial wall (septum) ▪ Floor Nasal cavity 4 Roof Floor Lateral Medial sphenoethmoidal recess Nasal cavity Superior conchae Superior meatus Inferior conchae Body of Middle conchae sphenoid Inferior meatus Middle meatus Narrow & formed - Separates it from Shows three horizontal bony projections, the Medial Wall (from behind the oral cavity. superior, middle & inferior conchae. (Nasal Septum) forward) by the: Osteocartilaginous - Formed by the hard - The cavity below each concha is called a meatus partition. 1. Body of sphenoid. (bony) palate. (named corresponding to the conchae). 2. Cribriform plate of Formed by: ethmoid bone. - The small space above the superior concha is 1. Perpendicular 3. Frontal bone. the sphenoethmoidal recess. plate of ethmoid 4. Nasal bone & bone. cartilage. - The conchae increase the surface area of the 2. Vomer. nasal cavity. 3. Septal cartilage. - The recess & meati receive the openings of the: Paranasal sinuses & Nasolacrimal duct. Nasal Mucosa & Respiratory Mucosa 5 Vestibule Nasal/olfactory mucosa Respiratory mucosa - It is delicate and contains olfactory nerve cells. - It is thick, ciliated, highly vascular and contains mucous glands & goblet cells, it lines the lower part of the nasal cavity. - It is present in the upper part of nasal cavity: ➔ On the Roof - Functions: moisten, clean & warm up the inspired air. ➔ On the lateral wall: upper surface of the ➔ The air is moistened by the secretion of numerous serous superior concha & the sphenoethmoidal glands. recess. ➔ The air is cleaned by the removal of the dust particles by ➔ On the medial wall: it lines the superior the ciliary action of the columnar ciliated epithelium that part of the nasal septum. covers the mucosa. ➔ The air is warmed by a submucosal venous plexus. - The vestibule is lined by skin. Nasal Mucosa & Respiratory Mucosa 6 Nerve supply Arterial supply & Venous supply Lymphatic drainage Olfactory mucosa is supplied by Arterial Supply: - The lymphatics from the olfactory nerves. - Branches of the: maxillary, facial & vestibule drain into: the ophthalmic arteries. submandibular lymph Nerves of general sensation are - The arteries make a rich anastomosis in the nodes. derived from: region of the vestibule & the anterior portion ● Ophthalmic nerves of the septum. - The rest of the cavity ● Maxillary nerves drains into the upper deep ● Autonomic fibers Venous Drainage: cervical lymph nodes. - Drain into the: facial, ophthalmic, and spheno-palatine veins. Paranasal Sinuses 7 posterior ethmoidal - They are air filled cavities located in the sinus bones around the nasal cavity: Ethmoid, Sphenoid, Frontal and Maxillae. sphenoidal sinus frontal Sinus - They are lined by respiratory mucosa which Maxillary sinus is continuous with the mucosa of the nasal Middle & anterior cavity. ethmoidal sinuses nasolacrimal duct. *Drain into the nasal cavity. Sphenoethmoidal recess sphenoidal sinus Functions Superior meatus posterior ethmoidal sinus ▪ Lighten the skull Middle meatus middle ethmoidal, maxillary, ▪ Act as resonance chambers for speech. frontal & the anterior ▪ Air conditioning: The respiratory ethmoidal sinuses mucosal lining helps in warming, cleaning and moistening the incoming air. Inferior meatus nasolacrimal duct Pharynx ● Muscular tube lying behind the nose, oral cavity and The deficient of the anterior wall 8 larynx. shows the following (from above ● Extends from the base of the skull to level downward): of the 6th cervical vertebra, where it is 1. Posterior nasal apertures. continuous with the esophagus. 2. Opening of the oral cavity. - Note: It starts at the nose and 3. Laryngeal inlet. continuous as the esophagus. Circular: Muscles arrangement of muscles Function the pharynx ● Propel the bolus of food down into the 1. Superior constrictor esophagus. (swallow) 2. Middle constrictor ● Lower fibers of the inferior A- Circular 3. Inferior constrictor constrictor (Cricopharyngeus) Longitudinal: muscles act as a sphincter, preventing the The three muscles overlap each entry of air into the esophagus other. between the acts of swallowing. 1. Stylopharyngeus Elevate the larynx and pharynx during B- Longitudinal 2. Salpingopharyngeus swallowing muscles 3. Palatopharyngeus Parts of pharynx 9 Nasopharynx Oropharynx Laryngopharynx - Extends from the base of the skull to - Extends from soft palate to - Extends from upper border of the soft palate. upper border of epiglottis. epiglottis to lower border of cricoid cartilage. - It lies behind the mouth - It lies behind the laryngeal inlet and (tongue). the posterior surface of larynx. Communicates with the nasal cavity Communicates with the oral Communicates with larynx through posterior nasal apertures. cavity through the through the laryngeal inlet. oropharyngeal isthmus. Pharyngeal tonsils (Adenoides) Lateral wall: A small depression situated on present in the submucosa covering 1. Palatopharyngeal either side of the laryngeal inlet is the Roof. fold. (Posterior) calle Piriform Fossa. 2. Palatoglossal fold. (Anterior) Lateral wall: 3. Palatine tonsil. - It is a common site for the lodging 1. Opening of auditory tube Located between them in a of foreign bodies. (middle ear). depression is the tonsillar fossa. 2. Tubal elevation (produced by - Branches of internal laryngeal posterior margins of the and recurrent laryngeal nerves lie auditory tube). 3. Tubal tonsil. deep to the mucous membrane of 4. Pharyngeal recess. the fossa and are vulnerable to 5. Salpingopharyngeal fold (raised injury during removal of a foreign by salpingo-pharyngeus body. muscle). Pharynx Supply and drainage: 10 Nerve supply Palatine tonsil: Arterial Venous Lymph - Two masses of lymphoid tissue supply drainage drainage Sensory Motor located in the lateral wall of the oropharynx in the tonsillar 1- Nasopharynx: - All the muscles 1- Ascending pharyngeal Deep Cervical fossa. Maxillary nerve. of pharynx are pharyngeal. venous plexus, lymph nodes 2- Oropharynx: supplied by the 2- Ascending which drains (either directly or - Each one is covered by mucous Glossopharyngeal pharyngeal palatine. into the internal indirectly) via membrane and laterally by nerve. plexus. 3- Facial. jugular vein. the fibrous tissue (capsule). 3- 4- Maxillary. retropharyngeal Laryngopharynx: Except for: the 5- Lingual. or Paratracheal Vagus nerve. Stylopharyngeus lymph nodes. - It reaches a maximum size which is supplied during childhood, after puberty by the it diminishes in size. glossopharyngeal nerve. MCQs Question 1: We can find the sphenoethmoidal recess on the: Question 5: Muscular tube lies behind the nose: 11 A. Roof A. Pharynx B. Floor B. Larynx C. Medial wall C. A&B D. Lateral wall D. None of the above Question 2: Which branches of the following arteries doesn’t supply the nasal mucosa? Question 6: Which muscle act as a sphincter? A. Maxillary A. Superior constrictor B. Ophthalmic B. Inferior constrictor C. Lingual C. Palatopharyngeus D. Facial D. Stylopharyngeus Question 3: The lymphatics from vestibule drains into the: Question 7: Laryngopharynx Communicates with larynx through the: A. Upper deep cervical A. Laryngeal inlet B. Superficial cervical B. Oropharyngeal isthmus C. Submental C. Posterior nasal apertures D. Submandibular D. Nasal cavity Question 4: We can find the opening of the posterior ethmoidal sinus in the: Question 8: The motor supply for the stylopharyngeus is: A. Middle meatus A. Pharyngeal plexus B. Superior meatus B. Glossopharyngeal nerve C. Sphenoethmoidal recess C. Maxillary nerve D. Inferior meatus D. Vagus nerve Answers: Q1.D- Q2.C -Q3.D -Q4.B- Q5.A- Q6.B-Q7.A- Q8.B Team members Boys team: Girls team : ● Khalid AL-Dossari ● Ajeed Al Rashoud ● Naif Al-Dossari ● Taif Alotaibi Best wishes ● Faisal Alqifari ● Noura Al Turki ● Salman Alagla ● Amirah Al-Zahrani ● Ziyad Al-jofan ● Alhanouf Al-haluli ● Suhail Basuhail ● Sara Al-Abdulkarem ● Ali Aldawood ● Rawan Al Zayed ● Khalid Nagshabandi ● Renad Al Haqbani ● Mohammed Al-huqbani ● Nouf Al Humaidhi ● Jehad Alorainy ● Jude Al Khalifah ● Khalid AlKhani ● Nouf Al Hussaini ● Omar Alammari ● Alwateen Al Balawi ● Rahaf Al Shabri ● Danah Al Halees ● Rema Al Mutawa Don't forget to leave ● Amirah Al Dakhilallah your feedback: Team leaders ● Maha Al Nahdi ● Ghaida Al Braithen ● Abdulrahman Shadid ● Ateen Almutairi.