Anatomy

1. LARYNX

2. LARYNX
• Voice box
• Serves as passage
• Extent:
• Root of the tongue to the
commencement of trachea

3. CARTILAGES OF LARYNX:
• Unpaired:
• Thyroid
• Cricoid
• Epiglottis
• Paired:
• Arytenoid
• Corniculate
• Cuneiform

4. MUSCLES OF LARYNX
• Cricothyroid
• Posterior cricoarytenoid
• Lateral cricoarytenoid
• Transverse arytenoid
• Oblique arytenoid
• Thyroarytenoid
• Ary-epiglotticus
• Thyro-epiglotticus
• vocalis

5. • Blood supply:
• Superior laryngeal branch of superior thyroid artery
• Inferior laryngeal branch of inferior thyroid artery
• Nerve supply:
• Motor supply:
• All muscles - recurrent laryngeal nerve
• Except cricothyroid - external laryngeal nerve
• Sensory supply:
• Mucosa above vocal folds – internal laryngeal nerve
• Mucosa below vocal folds – recurrent laryngeal nerve

6. TRACHEA
• Wind pipe
• Conduct air to lungs for respiration
• Continues from larynx
• Ends by dividing into two principal bronchus
• Made up of hyaline cartilage
• C-shaped cartilages
• Behind it is filled up trachealis muscle

7. MICROSCOPIC STRUCTURE
• Structure:
• Four layers:
• Mucosa
• Submucosa
• Cartilaginous layer/smooth
muscle layer
• Adventitia

8. • Mucosa:
• Lined by pseudostratified epithelium with
goblet cells
• Cell types:
• Ciliated columnar cells
• Goblet cells
• Basal cells
• Lamina propria:
• Underneath the epithelium
• Made up of loose connective tissue
• No definitive boundary between lamina
propria and submucosa

9. • Submucosa:
• Consists mixed seromucous glands
• Cartilaginous layer/smooth muscle
layer:
• Hyaline cartilage with perichondrium in
anterior 2/3rd
• Posteriorly cartilage is absent
• Trachealis muscle
• Adventitia:
• Outer layer
• Made up of connective tissue with collagen
and elastic fibers