Human voice is so complex that it not only conveys meaning, it also is capable of conveying subtle emotions. It is the most important physiological aspect that effectively starts to function immediately after birth.
“Hoarseness is a symptom of utmost significance
and calls for a separate consideration as a subject because
of the frequency of its occurrence as a distant signal of
malignancy and other conditions”
A useful Mnemonic to remember the causes of hoarseness of voice:
V - Vascular (thoracic aneurysm)
I - Inflammation
N - Neoplasm
D - Degenerative (Amyotrophic lateral sclerosis)
I - Intoxication (smoking / alcohol)
C - Congenital
A - Allergies (angioneurotic oedema)
T - Trauma / Thyroid surgery
E - Endocrinology (Reidel's struma)
This is one of the commonest causes of hoarseness of voice. Inflammatory causes could either be acute / chronic.
Acute inflammatory causes: include acute laryngitis, acute epiglottis, acute laryngotracheal bronchitis, diphtheria etc.
Chronic inflammatory causes include: chronic non specific laryngitis (due to gastro oesophageal reflux disorders, vocal abuse etc).
Chronic specific laryngitis (tuberculous / syphilitic laryngitis).
Acute vocal cord injuries can lead to vocal fold tears / hematoma causing hoarseness of voice. This condition resolves with complete voice rest.
Vocal cord polyp
Vocal cord cysts
Carcinoma vocal cords
Congenital vocal cord webs
Evaluation of hoarseness of voice should include:
A complete history should be elicited.
Laryngeal visualization : Indirect laryngoscopy / Direct laryngoscopy
Objective voice assessment: simplest method would be a tape recording of the voice in question. This method should be considered to be
Acoustic analysis: In this test voice is examined as electrical signals. The term fundamental frequency is used to measure the number of
vocal fold vibrations per second. A normal adult male vocal cord vibrates between 100 - 130 Hz, where as in females it vibrates at the
rate of 200 - 230 Hz. Abnormally high fundamental frequencies corrected for age and sex changes would indicate hyper contraction of
cricothyroid muscle representing a functional pathology or compensatory dysphonia.
The quality of voice is dependent on breath support. Even subtle respiratory problems can lead to changes in voice. Aerodynamic
measurements play a role in quantifying airflow during respiration and phonation. Pulmonary function tests may play a role in
identifying subtle respiratory problems.
Maximum phonation time: This is a measurement of the amount of time a patient can sustain a vowel sound in one breath.
Normal values range between 15 - 25 seconds. Decreased values indicate incomplete glottic closure or insufficient lung support.
Glottal air flow: This sensitive test captures the amount of air flowing through the glottis during phonation. This is measured in
cc/second by dividing the total volume of air flowing through the glottis by the amount of time in seconds. This gives information
about the lung capacity and the efficiency of vocal folds. Increased glottal flow is associated with incomplete closure of glottis.
The voice in patients with increased glottal flow is usually breathy / whispering in nature.
Decreased glottal air flow is seen in patients with spasmodic dysphonia due to hyperadduction of vocal folds.