Lecture Notes on the Larynx, Trachea, and Related Structures
Larynx Anatomy
- Key Structures:
- Adam's Apple: Also known as the thyroid cartilage.
- Epiglottis: Prevents food from entering the larynx.
- Cricoid Cartilage: Connects larynx to the trachea.
- Paired Cartilages:
- Arytenoid
- Corniculate
- Cuneiform
Differences between Males and Females
- Testosterone during puberty:
- Thickens and enlarges vocal cords in males, causing voice changes.
- Affects thyroid cartilage visibility, more pronounced in males.
- Estrogen in females prevents the size change of thyroid cartilage.
- Hyoid Bone: Anchors the tongue; aids in swallowing and talking.
Trachea Anatomy
- Structure: Rings (C-rings) keep it open, similar to a vacuum hose.
- Function: Allows air passage; prevents collapse regardless of pressure changes.
- C-Rings: Do not make a complete circle; the back is open to accommodate the esophagus.
Vocal Cords
- False Vocal Cords: Also known as ventricular folds.
- True Vocal Cords:
- Contains skeletal muscle and elastic ligament.
- Sound production involves air pushing past tightened vocal cords.
- Pitch and volume controlled by tension and airflow.
Speech Mechanics
- Involves: Pharynx, mouth, nasal cavity, sinuses, tongue, and lips.
- Pitch: Controlled by vocal fold tension.
- Volume: Controlled by the amount of air passed.
Health Considerations
- Laryngitis: Inflammation of the larynx.
- Larynx Cancer: Predominantly found in smokers and those with HPV.
Human Papillomavirus (HPV)
- HPV and Cancer:
- Major cause of cervical, anal, and throat cancer.
- Types 16 and 18 are significant in the U.S.
- Vaccination: Recommended to prevent HPV-related cancers.
Trachea and Bronchi
- Trachea: Extends from the larynx to primary bronchi.
- Bronchus Branching:
- Primary, secondary, and tertiary bronchi.
- Branch into bronchioles (no cartilage).
- Asthma and Anaphylaxis:
- Constriction of bronchioles makes breathing difficult.
- EpiPen use in emergencies to dilate airways.
Medical Interventions
- Tracheostomy/Tracheotomy: Reestablishes airflow in obstructions or long-term intubation.
- Intubation: Used during surgeries or respiratory issues; prolonged use may require tracheotomy to prevent vocal cord damage.
Bronchial Tree
- Hierarchy:
- Primary Bronchi → Secondary Bronchi → Tertiary Bronchi → Bronchioles → Terminal Bronchioles → Respiratory Bronchioles → Alveolar Ducts → Alveoli
- Function: Efficient air passage and gas exchange.
These notes capture key anatomical features, functions, health considerations, and interventions related to the larynx and trachea, providing a foundational understanding for further study.