Anatomyof
Larynx
Larynx (anterior)
Larynx (posterior)
Larynx (posterior)
Larynx (lateral)
Larynx (superior)
Larynx (superior)
Larynx (sagittal section)
Larynx (sagittal section)
Larynx (coronal section)
Vocal fold
Vocal fold
Laryngeal Cartilages
3 single & 3 paired
Single Paired
Epiglottis Arytenoid
Thyroid Corniculate (Santorini)
Cricoid Cuneiform (Wrisberg)
Cartilages (anterior)
Laryngeal Cartilages
Cartilages (posterior)
Cartilages (posterior)
Cartilage Histology
Elastic: Epiglottis, corniculate, cuneiform &
apex of arytenoid. Little or no calcification.
Hyaline: Thyroid, cricoid & remaining arytenoid.
Calcify as age advances. Ossification begins by
25-30 yr & is completed by 60 yr.
Indirect Laryngoscopy
Flexible LaryngoscopyLEFT RIGHT
Laryngeal cavity
1. Laryngeal inlet
2. Laryngeal Vestibule
3. Laryngeal Ventricle
4. Rima glottis
5. Subglottis
Pediatric Larynx
• Conical in shape & subglottis is narrowest part
• Positioned high (C3-C4)
• Moves higher during swallowing allowing
simultaneous breathing & feeding
• Loose sub-mucosal tissues (swell up easily)
• Soft cartilages that collapse easily
Membranes & Ligaments
• Extrinsic:
connect thyroid cartilage & epiglottis with
hyoid bone; cricoid cartilage with trachea.
• Intrinsic:
connect cartilages of larynx to each other.
Extrinsic
• Thyrohyoid
membrane
• Hyoepiglottic
ligament
• Cricotracheal
ligament
Intrinsic
Intrinsic
Intrinsic
1. Quadrangular membrane
Ary-epiglottic ligament Vestibular ligament
2. Crico-vocal membrane
Vocal ligament Cricothyroid membrane
3. Thyro-epiglottic ligament
Oncological Divisions
A. Supraglottis: laryngeal
inlet to apex of ventricle
B. Glottis: apex of
ventricle to 10 mm below
C. Subglottis: lower glottic
border to lower cricoid
border
Subsites
A. Supraglottis: 1. Epiglottis 2. Aryepiglottic
folds 3. Ventricular bands 4. Laryngeal
Ventricle
B. Glottis: 1. True vocal cords 2. Anterior
commissure 3. Posterior commissure
C. Subglottis
Intrinsic Muscles
A. Acting on vocal cords
Abduction Posterior crico-arytenoideus
Adduction Lateral crico-arytenoideus
Transverse inter-arytenoideus
Thyro-arytenoideus externa
Tension + lengthening Cricothyroid
Relaxation + shortening Vocalis
Intrinsic Muscles
B. Acting on laryngeal inlet
Opener Thyro-epiglottic
Closer Oblique inter-arytenoideus
Ary-epiglottic
Extrinsic MusclesPrimary Elevators Secondary Elevators
Stylopharyngeus Mylohyoid
Salpingopharyngeus Stylohyoid
Palatopharyngeus Geniohyoid
Thyrohyoid Digastric
Depressors
Sternohyoid Sternothyroid Omohyoid
Posterior cricoarytenoid
Lateral cricoarytenoid
Transverse Inter-arytenoid
Cricothyroid
Thyroarytenoid externa + Vocalis
Oblique Inter-arytenoid
Spaces of Larynx
Reinke’s space
Pre-epiglottic space
Para-glottic space
Communications
Shape of Glottis
Shape of Glottis
Quiet Respiration Forced Inspiration
Inspiration
Shape of Glottis
Normal voice Whisper
Normal phonation
Whisper
Mucous Membrane
• Stratified squamous epithelium:
Epiglottis (anterior surface + upper half of
posterior surface), upper part of aryepiglottic
folds & vocal cords
• Pseudo-stratified ciliated columnar
(respiratory) epithelium:
Rest of laryngeal mucous membrane
Nerve Supply
Superior Laryngeal Nerve:
• Internal: sensation to supraglottis & glottis
• External: motor to cricothyroid muscle
Recurrent Laryngeal Nerve:
• sensation to subglottis
• motor to all intrinsic muscles but cricothyroid
Blood Supply
Arterial supply:
• Laryngeal br. of superior & inferior thyroid
Venous drainage:
• Superior thyroid vein internal jugular vein
• Inferior thyroid vein innominate vein
Lymphatic Drainage
Supraglottis: via thyrohyoid membrane into upper
deep cervical nodes & thyroid gland
Subglottis: via cricothyroid membrane into
pretracheal + lower deep cervical nodes
Glottis: has no lymphatics