Hoarseness: Causes, Investigations, Differential Diagnosis

Hoarseness is defined as roughness of voice resulting
from variations of periodicity and/or intensity of consecutive
sound waves.
For production of normal voice, vocal cords should:
1. Be able to approximate properly with each other.
2. Have a proper size and stiffness.
3. Have an ability to vibrate regularly in response to air
column.
Any condition that interferes with the above functions
causes hoarseness.
(a) Loss of approximation may be seen in vocal cord paralysis
or fixation or a tumour coming in between the
vocal cords.
(b) Size of the cord may increase in oedema of the cord
or a tumour; there is a decrease in partial surgical
excision or fibrosis.
(c) Stiffness may decrease in paralysis, increase in spastic
dysphonia or fibrosis.
Cords may not be able to vibrate properly in the presence
of congestion, submucosal haemorrhages, nodule or
a polyp.

Aetiology:

Hoarseness is a symptom and not a disease per se . The
causes of hoarseness are summarised below:

Causes of hoarseness
1 . Inflammations
a.Acute: Acute laryngitis usually following
cold, influenza, exanthematous
fever, laryngo-tracheo-bronchitis,
diphtheria
b.Chronic(i) Specific. Tuberculosis, syphilis,
scleroma, fungal infections
(ii) Non-specific. Chronic laryngitis,
atrophic laryngitis
2. Tumours
a.Benign: Papilloma (so litary and multiple),
haemangioma, chondroma
fibroma, leukoplakia

b.Malignant: Carcinoma
c.Tumour-like masses: Vocal nodule, voca l polyp,
angiofibroma, amyloid tumour,
contact ulcer, cysts, laryngocele
3. Trauma: Submucosal haemorrhage,
laryngeal trauma (blunt and
sharp), foreign bodies, intubation

4. Paralysis: Paralysis of recurrent, superior
laryngeal Or" both nerves
5. Fixation of cords: Arthritis or fixation of cricoarytenoid
joints
6. Congenital: Laryngeal web, cyst, laryngocele
7. Miscellaneous: Dysphonia plica ventri cul ar'is,
myxoedema, gout
8. Functional: Hysterical aphonia

Investigations
1. History. Mode of onset and duration of illness,
patient's occupation, habits and associated complaints
are important and would often help to elucidate
the cause. Any hoarseness persisting for more ti-um
three weeks deserves examination of larynx. Malignancy
should be excluded in patients above 40 years.
2. Indirect laryngoscopy. Many of the local laryngeal
causes can be diagnosed.
3. Examination of neck, chest, cardiovascular and neurological
system would help to find cause for laryngeal
paralysis.
4. Laboratory investigations and radiological examination
should be done as per dictates of the cause suspected
on clinical examination.
5. Direct laryngoscopy and microlaryngoscopy help
in detailed examination, biopsy of the lesions and
assessment of the mobility of cricoarytenoid joints.
6. Bronchoscopy and oesophagoscopy may be required
in cases of paralytic lesions of the cord to exclude
malignancy.