Evaluation of the vocal tract

In the diagnosis of diseases related to the vocal tract, including vocal folds, a correct assessment of their functioning by a specialist in ENT or phoniatry is essential.

This assessment should be comprehensive and begin with a detailed history of the patient. This is because the condition of the vocal folds can be influenced by factors such as hormonal conditions, in particular related to hormone treatment, allergic tendencies and complaints of all kinds, habits, with particular reference to addictions such as smoking, and environmental conditions.

Another element in the assessment of the functioning of the vocal tract is the ENT examination, checking nasal patency, the state of the mucous membranes, identifying any inflammatory foci as well as the functioning of the palate. The key to the ENT examination is to determine the morphology of the vocal folds, i.e. their colour, smoothness, mobility and behaviour when producing sounds.

Vocalemission is also important in determining the condition of the vocal folds. This largely concerns the tone and timbre of our voice.

Thestroboscopic examination is performed to determine the phonatory activity of the glottis, namely showing the nature of the vocal folds' vibration, amplitude, marginal shift and phonatory shortness.

If necessary, a tomographic examination of the larynx is useful, which provides an image of the laryngeal structures to identify any asymmetries in the physiological arrangement of the organ.

During examination of the vocal organ, the age of the patient should also be taken into account. This is particularly important in situations where the examination is carried out in order to diagnose an occupational disease related to voice work, as in the case of teachers or singers. The changes that occur with age in the human body affect structures throughout the body, including the vocal tract. Any type of hypertrophic abnormality, which is most common in the group of people who work with their voice, should be subjected to histological evaluation. The form in which the material for the examination is taken is biopsy, but there is an alternative examination that allows the appropriate slice to be taken for examination, namely exfoliative stroboscopy. However, this is such an invasive test that, in effect, causes scarring of the vocal fold structure, disrupting its normal mechanics. [1]

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Abnormalities

The main factor that creates favourable conditions for the development of any changes in the vocal tract and vocal folds is excessive vocal effort. It can lead to changes in the structure of the mucous membranes of the vocal folds proper. This mainly relates to the Renician subepithelial space, where the accumulation of fluid causes elevation of the squamous multilayer epithelium, which itself generally remains unchanged, leading to clinical changes in the form of polyps. Polyps may have the charter of a localised lesion, but in some situations the entire vocal fold structure may be involved. This type, polypoid swelling of the vocal fold, is referred to as Renician's oedema, which is a condition that overwhelmingly affects women and is strongly associated with hormonal changes.

Another type of abnormality that can occur on the structures of the vocal folds are vocal nodules, occurring bilaterally, on the anterior aspect of the vocal fold, halfway up. The nodules resemble polyps in structure, but with the difference that the fibrotic process within the lesion is much more advanced.

Granulomas are another type of lesion associated with the vocal folds. They are otherwise known as contact ulceration and occur mainly within the vocal process, in the form of accumulated granulation tissue. The cause of their occurrence and formation is trauma to this area as well as abnormal phonation or acidic gastric contents that reach this area due to other disorders, such as reflux disease.