Nose and Pharynx

1. Nose and Pharynx Dr. Sama ul Haque

2. Objectives • Discuss the anatomical structure of nose. • Define Paranasal sinuses. • Describe the anatomical structure of pharynx. • Enlist the extrinsic and intrinsic muscles of the pharynx with their nerve supply and actions.

3. Organization and Functions of the Respiratory System • Consists of an upper respiratory tract (nose to larynx) and a lower respiratory tract (trachea onwards). • Conducting portion transports air. - includes the nose, nasal cavity, pharynx, larynx, trachea, bronchi and bronchioles. • Respiratory portion carries out gas exchange. - composed of small airways called respiratory bronchioles and alveolar ducts as well as air sacs called alveoli.

5. Upper Respiratory Tract • Nose • Nasal cavity • Paranasal sinuses • Pharynx (throat) • Larynx

6. Upper Respiratory Tract

7. Structure of the Nose

12. Nose • Olfactory mucosa: Mucous membranes that contain smell receptors. • Respiratory mucosa: Pseudostratified ciliated columnar epithelium containing goblet cells that secrete mucus which traps inhaled particles.

14. Paranasal sinuses

15. Paranasal Sinuses • Frontal, ethmoidal, sphenoidal, maxillary. • Decrease skull bone weight. • Warm, moisten and filter incoming air. • Add resonance to voice. • Communicate with the nasal cavity by ducts.

18. Sphenoethmoidal recess: Sphenoidal air sinus Superior meatus:Posterior ethmoidal air sinus Middle meatus : Bulla ethmoidalis: Middle ethmoidal air sinus Hiatus semilunaris: Frontal air sinus Maxillary air sinus Middle ethmoidal Inferior meatus: Nasolacrimal duct Drainage of the Paranasal Sinuses

20. Blood supply of the nasal cavity:-

21. Functions of the Nose • Provides an airway for respiration • Moistens and warms entering air • Filters and cleans inspired air • Resonating chamber for speech • Detects odors in the air stream

22. Pharynx • Common space used by both the respiratory and digestive systems. • Commonly called the throat. • Walls are lined by a mucosa and contain skeletal muscles that are primarily used for swallowing. • Partitioned into three adjoining regions: Nasopharynx Oropharynx Laryngopharynx

23. Pharynx

24. Divisions of the pharynx

25. Nasopharynx • Located directly posterior to the nasal cavity and superior to the soft palate, which separates the oral cavity. • Normally, only air passes through. • In the lateral walls of the nasopharynx, paired auditory/eustachian tubes connect the nasopharynx to the middle ear. • Posterior nasopharynx wall also houses a single pharyngeal tonsil (commonly called the Adenoids).

27. Oropharynx • Middle pharyngeal region. • Lies immediately posterior to the oral cavity. • Common respiratory and digestive pathway through which both air and swallowed food and drink pass. • Lymphatic organs here provide the first line of defense against ingested or inhaled foreign materials. Palatine tonsils are on the lateral wall between the arches, and the lingual tonsils are at the base of the tongue.

29. Laryngopharynx • Inferior, narrowed region of the pharynx. • Terminates at the superior border of the esophagus and the epiglottis of the larynx. • Permits passage of both food and air.

36. Functions of the Pharynx • Provides a passageway for Air & Food • Moistens and warms entering air • Taste • Protection • Speech

37. Thank you