Laryngeal Examination Techniques

Visual Documentation of the Larynx

• Laryngeal endoscopy, using flexible or rigid endoscopes, is used to examine vocal fold structure and gross function.
• Videostroboscopy examines vocal fold vibration patterns and the relationship between the body and the cover.
• Laryngeal high-speed videoendoscopy complements endoscopy and stroboscopy, showing details of short and aperiodic vibration and quantifying vibration parameters.
• Narrow-band imaging uses tissue light absorption characteristics to show vascular detail.
• Each vocal fold visualization tool contributes uniquely to assessment.

Endoscopy: Assessment Using Continuous Light

• Endoscopic examination with continuous light provides information about structure and gross movement.
• Laryngeal structure abnormalities and asymmetries (valleculae, piriform sinuses, epiglottis, aryepiglottic folds, ventricular folds, posterior glottal rim) are observed.
• Pitch changes during sustained sounds (e.g., "ee") can aid in visualization.
• Signs of irritation or laryngopharyngeal reflux (edema, erythema, cobblestoning, interarytenoid bar, pseudosulcus) are noted.

Arytenoid and Vocal Fold Motion

• Arytenoid movement and position assess cricoarytenoid joint and recurrent laryngeal nerve integrity.
• Mobility and symmetry are described, and immobile arytenoids are further categorized by position and axis.
• Observing patients during "ee"-sniff or cough, or rapid pitch glides, helps assess symmetry of posterior and lateral pharyngeal wall bulging.

Mucus

• Thickened mucus often adheres to vocal fold edges or the superior surface.
• Presence of thick mucus can relate to lack of hydration or chronic irritation.
• Mucus in the pyriform sinuses can indicate poor laryngeal sensation, weak lateral pharyngeal walls, or swallowing issues.

Supraglottal Activity

• Supraglottal activity refers to motion above vocal folds.
• Supraglottal constriction can be a normal variant or a sign of disordered voice.
• Sustained supraglottal constriction can indicate muscle tension dysphonia.

Vocal Fold Edges

• The degree of vocal fold smoothness and regularity is described.
• Irregularities related to lesions or convex/concave ("bowed") edges are noted.
• Bowing is a descriptive term, not a disorder.

Protocol and Limitations

• Endoscopic examination protocols include rest and deep breathing, easy cough, sustained "ee," rapid pitch glides, quiet/loud phonation, and sentence/conversation.
• Endoscopic observations offer limited information for understanding voice disorders, as they don't show vibratory patterns.

Assessment With Stroboscopy

• Videostroboscopy assesses vocal fold vibration patterns.
• Healthy vocal folds consist of a pliable cover (epithelium and superficial lamina propria) and a stiffer body (intermediate and deep lamina propria, and thyroarytenoid muscle).
• Muscle contraction positions and shapes vocal folds (adduction/abduction, lengthening/shortening/bulging) for vibration.

Glottal Closure

• Closure patterns (complete or incomplete; gap shape) are noted at the most closed point of vibration.
• Different patterns (complete, posterior gap, anterior gap) of gap shapes are common in men and women respectively.
• Assessment focuses on vocal fold contact at MCPL.

Mucosal Pliability and Stiffness

• Amplitude of vibration (excursion from midline) is assessed.
• Normal excursion is approximately one-third of the vocal fold width.
• Decreased amplitude indicates increased stiffness, lesions (polyps, cysts, papillomas, scarring, hyperfunction).
• Increased amplitude represents decreased tonicity (paresis or atrophy).

Laryngeal High-Speed Videoendoscopy (LHSV)

• LHSV provides temporal resolution to view vocal fold vibration regardless of the duration or severity of dysphonia.
• LHSV allows observing vocal fold vibration at rates of up to 20,000 frames per second.
• LHSV offers assessment of onset and offset, ventricular folds, asymmetries between right and left vocal fold vibration, and frequency differences.

Narrow-Band Imaging (NBI)

• NBI uses light absorption differences to highlight vascular structures.
• Blue light is absorbed better by hemoglobin, highlighting vascular patterns.
• NBI improves detection of recurrent respiratory papillomatosis and screens for malignancies.
• NBI is useful for distinguishing between suspicious and benign tissue, helping in clinical decision-making.