nose ppt

• An Anatomical Journey Through the Nose

  
• PRSENTATION BY: GROUP 2
• TOPIC OUTLINE
• TOPIC OUTLINE


  • External Nose
  • Nasal Cavity
  • Mucous Membrane of Nasal Cavity
  • Paranasal Cavity
  • The Larynx
  • Membranes & Legaments of Larynx
  • Muscles of Larynx
  • Mucous Membrane of the Larynx
  • Trachea
  • Endo. Glands in the Head and Neck; Pituitary Gland and Pineal Gland
  • Thyroid Gland
  • Parathyroid Gland

  
• External nose


  Has two elliptical orifices called the nostrils, which are separated from each other by the nasal septum. The framework of the external nose is made up above by the nasal bones, the frontal processes of the maxillae, and the nasal part of the frontal bone. Beside, the framework is formed of plates of hyaline cartilage.

  
• BLOOD SUPPLY OF THE EXTERNAL NOSE

  
• Facial artery


  Loops upward close to the outer surface of the pharynx and the tonsil. It lies deep to the submandibular salivary gland and emerges and bends around the lower border of the mandible. It then ascends over the face close to the anterior border of the masseter muscle. The artery then ascends around the lateral margin of the mouth and terminates at the medial angle of the eye.

  
• NERVE SUPPLY OF THE EXTERNAL NOSE
• Ophthalmic nerve


  Purely sensory. It runs forward in the lateral wall of the cavernous sinus in the middle cranial fossa and divides into three branches, the lacrimal, frontal, and nasociliary nerves, which enter the orbital cavity through the superior orbital fissure.

  
• Nasociliary nerve


  Crosses the optic nerve, runs forward on the upper border of the medial rectus muscle and continues as the anterior ethmoid nerve through the anterior ethmoidal foramen to enter the cranial cavity. It then descends through a slit at the side of thecrista galli to enter the nasal cavity. It gives off two internal nasal branches and it then supplies the skin of the tip of the nose with the external nasal nerve.

  
• Branches of nasociliary nerve


  • Sensory fibers to the ciliary ganglion
  • Long ciliary nerves that contain sympathetic fibers to the dilator pupillae muscle and sensory fibers to the cornea
  • Infratrochlear nerve that supplies the skin of the eyelids
  • Posterior ethmoidal nerve that is sensory to the ethmoid and sphenoid sinuses
• Maxillary nerve


  Arises from the trigeminal ganglion in the middle cranial fossa. It passes forward in the lateral wall of the cavernous sinus and leaves the skull through the foramen rotundum and crosses the pterygopalatine fossa to enter the orbit through the inferior orbital fissure.

  
• NASAL CAVITY

  
• Nasal cavity


  Extends from the nostrils in front to the posterior nasal apertures or choanae behind, where the nose opens into the nasopharynx. The nasal vestibule is the area of the nasal cavity lying just inside the nostril.

  
• Nasal septum


  Divides the nasal cavity into right and left halves. It is made up of the septal cartilage, the vertical plate of the ethmoid, and the vomer.

  
• Walls of nasal cavity


  • Floor
  • Roof
  • Lateral wall
  • Medial or septal wall

  
• Floor


  Formed by the palatine process of the maxilla and the horizontal plate of the palatine bone.

  
• Roof


  Narrow, formed anteriorly beneath the bridge of the nose by the nasal and frontal bones, in the middle by the cribriform plate of the ethmoid, located beneath the anterior cranial fossa, and posteriorly by the downward sloping body of the sphenoid.

  
• Lateral wall


  Has three projections of bone called the superior, middle, and inferior nasal conchae.

  
• Space below each concha


  Called a meatus.
• Sphenoethmoidal recess


  Small area above the superior concha, receives the opening of the sphenoid air sinus.

  
• Superior meatus


  Lies below the superior concha, receives the openings of the posterior ethmoid sinuses.
• Middle meatus


  Lies below the middleconcha. It has a rounded swelling called the bulla ethmoidalis that is formed by the middle ethmoidal air sinuses, which open on its upper border. A curved opening, the hiatus semilunaris, lies just below the bulla.
• Hiatus semilunaris


  Anterior end leads into a funnel-shaped channel called the infundibulum, which is continuous with the frontal sinus.

  
• Maxillary sinus


  Opens into the middle meatus through the hiatus semilunaris.
• Inferior meatus


  Lies below the inferior concha and receives the opening of the lower end of the nasolacrimal duct, which is guarded by a fold of mucous membrane.
• Medial wall


  Formed by the nasal septum. The upper part is formed by the vertical plate of the ethmoid and the vomer. The anterior part is formed by the septal cartilage. The septum rarely lies in the midline, thus increasing the size of one half of the nasal cavity and decreasing the size of the other.

  
• Vestibule


  Lined with modified skin and has coarse hairs.
• MUCOUS MEMBRANE OF THE NASAL CAVITY

  
• Area above the super concha


  Lined with olfactory mucous membrane and contains nerve endings sensitive to the reception of smell.

  
• Large plexus of veins


  Present in the submucous connective tissue in the respiratory region.
• Lower part of the nasal cavity

  Lined with respiratory mucous membrane.

  
• FUNCTION OF WARM BLOOD AND MUCUS OF MUCOUS MEMBRANE
• Warm blood in the venous plexuses

  Serves to heat up the inspired air as it enters the respiratory system.
• Mucus on the surfaces of the conchae


  Traps foreign particles and organisms in the inspired air, which are then swallowed and destroyed by gastric acid.
• NERVE SUPPLY OF THE NASAL CAVITY

  
• Olfactory nerves


  From the olfactory mucous membrane ascend through the cribriform plate of the ethmoid bone to the olfactory bulbs.

  
• Nerves of ordinary sensation


  Ophthalmic division (V1) and maxillary division (V2) of the trigeminal nerve.
• BLOOD SUPPLY OF THE NASAL CAVITY

  
• Maxillary artery


  Arterial supply to the nasal cavity.