Laryngology and Voice Disorders
Core concepts
Know the layered structure of the vocal fold (epithelium, superficial lamina propria, vocal ligament, deep lamina propria, muscle) and how this determines vibration and the mucosal wave. Understand the physiology of phonation: subglottic pressure, glottal airflow, and the myoelastic-aerodynamic theory. Be able to interpret videostroboscopy findings such as reduced mucosal wave, glottal closure patterns, and lesions (nodules, polyps, cysts, Reinke edema). Know the causes of hoarseness and when to suspect malignancy.
Traps
A frequent trap is confusing vocal nodules (bilateral, at the junction of anterior and middle thirds) with polyps (often unilateral and related to trauma). Another is assuming all hoarseness is benign; any hoarseness lasting more than a few weeks in a smoker or drinker requires laryngoscopy to exclude cancer. Questions on spasmodic dysphonia often test the difference between adductor (strained, broken speech) and abductor (breathy breaks) types. Do not overlook laryngopharyngeal reflux as a cause of chronic throat clearing and posterior laryngeal erythema.
Worked example
A teacher develops progressive hoarseness with bilateral symmetric lesions at the midpoint of the vocal folds. This pattern suggests vocal nodules from phonotrauma; initial management is voice therapy, not surgery.