Docstoc

ANATOMY OF LARYNX & TRACHEOBRONCHIAL TREE

Document Sample
ANATOMY OF LARYNX & TRACHEOBRONCHIAL TREE Powered By Docstoc
					ANATOMY OF LARYNX &
 TRACHEOBRONCHIAL
       TREE

 BRIG MUHAMMAD ASHFAQ
    MBBS,FCPS,OJT(UK)
       ADVISOR ENT
                         The Larynx
• The larynx is a 5-7 cm long
  structure.
   • Its upper boundary starts at
     the tip of the epiglottis,
     opposite the 3rd to 4th,
     cervical vertebra.

• Its lower end is at the lower
  border of the cricoid
  cartilage.
   • This lies opposite the 6th
     cervical vertebra.



                                      2
               LARYNX
   OUTLINE
   I. CARTILAGES
   II. LIGAMENTS
   III. MUSCLES
   IV. TERMS/AREAS
   V. INNERVATION
   VI. BLOOD SUPPLY
   VII. LYMPHATICS
   VIII. OBSTRUCTION OF LARYNX
 Cartilages connected by
  membranes and ligaments,
  moved by muscles
 Functions:
 1) Sound production
 2) Closure of Respiratory
  System - allows increase in
  Abdominal Pressure
     I. LARYNX: CARTILAGES
  A. THYROID CARTILAGE – Shield shaped
  - has Sup. & Inf. Horns from upper & lower edges
       LaryngealProminence           Sup. Horns




- Inf. horns make synovial hinges joint with Cricoid Cartilage;
- Laryngeal Prominence = Adam’s Apple, more prominent in
males
  LARYNX: CARTILAGES

                      B. CRICOID complete
                      ring of cartilage has
                      narrow Arch ant.,
          Lamina of   broad Lamina post.
          cricoid


                           Lamina of
                           cricoid




Arch of
cricoid
LARYNX: CARTILAGES
         C. Arytenoid – 2 pyramidal
         shaped cartilages above lamina –
         have synovial joints with Cricoid
         permit Swivel = Rotate Sliding =
         Ab/Adduct

         D. Corniculate - nodules above
         arytenoids in aryepiglottic folds

         E. Cuneiform – rod shaped,
         above corniculate cartilages
    LARYNX: CARTILAGES

F. EPIGLOTTIS
-leaf shaped cartilage
posterior to root of tongue

- connected to body of hyoid
 and post side of thyroid
cartilage
     II. LIGAMENTS OF LARYNX

                1. Thyrohyoid Membrane links
Median             larynx to hyoid;Median
Thyrohyoid         Thyrohyoid Ligament –
Ligament
                   thickened midline part

                2. Cricothyroid Membrane
                links thyroid to cricoid; Median
 Median         Cricothyroid Ligament –
 Cricothyroid   thickened midline part
 Ligament
                3. Cricotracheal ligament links
                Cricoid to first tracheal cartilage
               The Larynx: Anatomy



   The thyrohyoid membrane
    forms a C-shaped barrier
    around the anterior and lateral
    walls of the supraglottis, and
    inferiorly becomes confluent
    with the connective tissue in
    the perichondrium of the
    tracheal cartilaginous rings.



                                      10
STRUCTURAL LIGAMENTS
      4. Quadrangular
      Membrane links Arytenoid
      To epiglottis
   STRUCTURAL LIGAMENTS




                      Aryepiglottic Folds –
                      overlie Quadrangular
                      membrane
Arytenoid cartilage
STRUCTURAL LIGAMENTS

           Lower free edge of
           Quadrangular membrane is
           Called Vestibular Ligament;
           deep to Vestibular (False
           Vocal) Folds
                      B. FUNCTIONAL
                        LIGAMENTS
                                  Conus Elasticus -
                                  Vibrating lips that
                                  arise
                                  from entire upper
                                  edge of
                                  arch of cricoid
                                  Attach: ant. to
                                  Thyroid, post. to
Vocal Ligaments -                 Arytenoid
Upper free Edges
Deep to Vocal Folds

                                  Rima Glottidis -
                                  Opening Between
                                  Vocal ligaments
                 The Larynx: Anatomy
   The vocal ligaments, are attached
    posteriorly to the apex of the
    arytenoids and corniculates. The
    cuneiforms extend laterally, between
    the layers of the vocal cords, from the
    anterior aspect of the
    arytenocorniculate complex.


   The epiglottis is attached to the base
    of the tongue by a median and two
    lateral glossoepiglottic folds.



                                              15
                   B. FUNCTIONAL
                     LIGAMENTS
   (In Coronal Section)
   Conus Elasticus Functions
   1) Sound Production – Vibrate
    like lips of trumpet player;
   2) Close Rima Glottidis stops
    outflow air, upward movement
    of diaphragm - when contract
    abdominal muscle pressure
    increases in abdominal cavity;
    occurs in childbirth, defecation
         Laryngoscopic view of Larynx
                                                  Posterior
                                                 Commissure
Superior surface anatomy:
                            True
                            Vocal
                            Cords
                       Ventricle



                      False
                      Vocal
                      Cords


                                     Anterior                 Aryepiglottic
                                    Commissure                   Fold
        III. MUSCLES OF LARYNX
   A. Extrinsic muscles (ex.
    hyoid muscles) - Move
    whole larynx as in
    swallowing
   B. Intrinsic Muscles
   1) change tension in vocal
    lig ..changes pitch:-
    increase tension raises pitch,
                 - decreased
    tension lowers pitch
                                     1) CRICOTHYROID M. -
   2) open & close Rima             Tenses
    Glottidis                        Vocal Ligament
                                     Increasing Pitch
III. MUSCLES OF LARYNX



            2)THYROARYTENOID
            MUSCLE -
            Relaxes Vocal Ligaments
            Decreases pitch
III. MUSCLES OF LARYNX

      5) ARYTENOID
      (Transverse and oblique
      arytenoid) - Adduct
      vocal folds

      4) LATERAL
      CRICOARYTENOID
      - Adduct vocal folds

      3) POSTERIOR
      CRICOARYTENOID
      – Abducts vocal fold
III. MUSCLES OF LARYNX

             5) ARYEPIGLOTTIC
             MUSCLE Pulls
             epiglottis down During
             swallowing

             -Covers inlet to larynx

             - Not necessary in
             adult humans
TERMS ASSOCIATED WITH
       LARYNX
          VESTIBULE - inlet above false
          vocal folds

          VESTIBULAR (FALSE VOCAL)
          FOLDS - overlie vestibular
          Ligaments

          VENTRICLE - area between true
          and false vocal folds; lateral
          extension is Laryngeal
          Sinus

          VOCAL (TRUE VOCAL) FOLDS
          - overlie vocal ligaments
                         The Larynx
                                                 Pyriform
                                                  Sinus

  Superior surface anatomy:


VALLECULAE
-depressions (2) Between Med &
Lat Glossoepiglottic Folds
-Food/objects Lodge in Valleculae



                                    Epiglottis   Vallecula
         Laryngoscopic view of Larynx
                                                  Posterior
                                                 Commissure
Superior surface anatomy:
                            True
                            Vocal
  Major Landmarks           Cords
                       Ventricle



                      False
                      Vocal
                      Cords


                                     Anterior                 Aryepiglottic
                                    Commissure                   Fold
                       The Larynx
                                                     Posterior Wall
                                                    Of Hypopharynx
Superior surface anatomy:

  Major Landmarks
                      Corniculate
                      Tubercle on
                       Arytenoid
                       Cartilage




                        Cuneiform
                         Tubercle

                                    Aryepiglottic
                                       Fold
                        The Larynx
                                        Arytenoid
                                        Cartilage
Superior surface anatomy:

  Major Landmarks
                                 True
                                Vocal
                                Cords

                    Ventricle



                                False
                                Vocal
                                Cords
                          The Larynx     Cartilaginous
                                           Rings of
                                           Trachea
Superior surface anatomy:

  Major Landmarks
  to look for           Vocal Cord
                        Sulcus (on
                        True Vocal
                          Cords)


                False
                Vocal
                Cords
                               Cricoid     True
                                Ring      Vocal
                                          Cords
QUIZ……This is the..

                   A.   The epiglottis
                   B.   The ventricle
                   C.   The arytenoid cartilage
                   D.   The true vocal cord
                   E.   The false vocal cord


 Click for correct answer:    B
          V. NERVES OF LARYNX –
              Branches of Vagus
   A. Superior Laryngeal N. divides to
   1. Internal Laryngeal N.
   -GVA Sensory to Larynx Above
    True Vocal Folds
   2. External Laryngeal N.
   -SVE Motor to Cricothyroid

   B. Recurrent Laryngeal N.
   - GVA Sensory to Larynx Below
    True Vocal Folds
   - SVE motor to all other Muscles of
    Larynx
Blood supply
        Arterial
                   sup. laryngeal artery
                   inf. Laryngeal artery

        Venous
                   sup. & inf. Thyroid
                   veins
VII. LARYNX - LYMPHATICS

   Superior Deep Cervical
    Nodes -Larynx above
    true vocal folds

   Inferior Deep Cervical
    Nodes- Larynx below
    true vocal folds
Laryngeal function: Airway Protection

 The glottis: open for inspiration and closed for swallowing




                 Open                   Closed


                                                               34
Laryngeal function: Phonation

The vocal cords: Adducted for phonation; abducted for
                     inspiration




   Adducted: Talking       Abducted: Breathing


                                                        35
 Laryngeal function: Phonation



The vocal cords open
and close while talking




                                 36
TRACHEOBRONCHIAL
  TREE ANATOMY
           Tracheobronchial Tree
     Two Divisions
     Cartilaginous Airways
     – Primarily conducting airways; no gas exchange.
     Noncartilaginous Airways
     – Both conducting airways and sites of gas exchange.
     Dichotomous Branching
     Each airway divides into two “daughter” branches
     Each division (bifurcation) gives rise to a new
   generation of airways
     As airways divide, they become
     Shorter
     Narrower
     More numerous
       Cartilaginous Airways

   Trachea
   Main Stem Bronchi
   Lobar Bronchi
   Segmental Bronchi
   Subsegmental Bronchi
                   TRACHEA
   Generation 0
   11 – 13 cm long and 1.5 – 2.5 cm wide.
   Extends from Cricoid cartilage (6th cervical
   vertebrae) to the 2nd costal cartilage or 5th
   thoracic vertebrae.
   C6 – T5
   15 - 20 C-shaped cartilages supports the
   trachea.
   Posterior wall is contiguous with esophagus
                   TRACHEA
   The end of the trachea is called the carina.
      This is the division of the trachea into the right
       and left mainstem bronchi.
      Air is 100% saturated with water vapor and is
    . warmed to 37 °C (body temperature).
      The carina is located at approximately T5 or
      the Angle of Louis.
   The surgical opening into the trachea is
      called a tracheostomy.
        2nd or 3rd tracheal ring.
              Main Stem Bronchi

   Generation 1
      Trachea divides into the right and left mainstem bronchi
    – one for each lung
      Right Mainstem is wider, shorter and more vertical
      Branches at a 25 degree angle
      Left Mainstem
            Branches at a 40 – 60 angle
      Infants
            Both mainstem bronchi form a 55 angle with the
         trachea
                Lobar Bronchi

   Generation 2
   Lobar Bronchi correlate to the number of lobes of
    the lung.
   The right mainstem bronchi will divide into the
    right upper, right middle and right lower lobe
    bronchi.
   The left mainstem bronchi will divide into the
    left upper and left lower lobe bronchi.
          Segmental Bronchi

 Generation 3
 Correlate with the segments of the lung.
 There are 10 segmental bronchi on the right.
 There are 8 segmental bronchi on the
  left.
       Subsegmental Bronchi

 4th to 9th Generations
 1 to 4 mm in diameter
 Connective tissue containing:
    -Nerves
    -Lymphatics
    -Bronchial Arteries
      Non-Cartilaginous Airways
   Bronchioles
          10th to 15th Generation.
          1 mm in diameter.
          Simple cuboidal epithelium.
          No cartilage.
   Terminal Bronchioles
          Less than 0.5 mm in diameter.
          No cartilage (lack of support).
          Cilia and mucous glands disappear.
          Clara Cells appear
          Inter-bronchiole connections called Canals of
          Lambert begin to appear.
           Blood Supply to the
          Tracheobronchial Tree
   Bronchial Blood Supply
       Bronchial arteries nourish the tracheobronchial tree
       The arteries arise from the aorta and follow the
       tracheobronchial tree as far as the terminal
        bronchioles.
       Beyond the terminal bronchioles pulmonary arteries &
       capillaries feed the airways & alveoli.
       Normal bronchial blood flow is approximately 1% of
        the cardiac output.
       Also feed the mediastinal lymph nodes, pulmonary
        nerves, part of the esophagus and the visceral pleura
QUESTIONS
   ?

				
DOCUMENT INFO
Stats:
views:236
posted:7/7/2012
language:English
pages:49