Laryngoscopy: Exploring the Procedure and Its Importance

Definition

Laryngoscopy consists of the visualization of the larynx and vocal cords using a laryngoscope. The laryngoscope is a diagnostic instrument used in the field of Otorhinolaryngology and Phoniatrics, consisting of an optical system (a mirror or an optical fiber) and a light source (external or fiber-optic). Depending on the type of laryngoscope used, the laryngoscopic technique can be classified

• Indirect laryngoscopy: the examination is performed using different instruments that allow visualization of the larynx and vocal cords indirectly. Within this type, the most commonly used laryngoscopies are: reflex laryngoscopy (it is based on the use of mirrors placed inside the mouth and a light source, it allows us to obtain a mirror or indirect image of the studied area) , microlaryngoscopy (similar to the previous one, incorporating a microscope), flexible fibroscopy (uses a flexible fiber optic endoscope that incorporates a light source.) and telelaryngoscopy (uses a rigid endoscope that incorporates an optical system and a light source ).
• Direct laryngoscopy: the examination is performed using instruments that allow direct visualization of the larynx. It requires the use of general anesthesia.

How is the study done?

Laryngoscopy is performed by the specialist in Otolaryngology and Phoniatrics and is usually done in your office. In reflex laryngoscopy and microlaryngoscopy, the patient remains seated on an armchair and will be asked to keep his mouth open during the study. The specialist will hold the patient's tongue with a sterile gauze and will insert some small mirrors of different sizes onto which they will project an external light that will allow the visualization of the larynx and vocal cords in the form of a mirror or inverted image. The use of sedatives or anesthetics is not necessary.

In the flexible fiberscopy the patient remains seated comfortably in an armchair, with the head directed forward and the stifle slightly inclined downwards. The patient is asked to breathe normally through the mouth while the examiner slowly inserts the endoscope (shaped like a rubber or wire) through one nostril; then you are asked to begin to breathe through your nose until the scope is positioned in the larynx. Once the placement is finished, you will be asked to perform different actions such as whistling, speaking or knife, to study the different functions of the larynx and vocal cords. The study does not require the use of sedatives or anesthetics.

In the telelaryngoscopy the patient remains seated on an armchair, the position of the head and chin will depend on the angle of the chosen endoscope, the doctor should indicate to the patient how to proceed. The introduction of the endoscope is done through the mouth and the specialist will often hold the patient's tongue with the help of sterile gauze. It may require the use of an anesthetic prior to the introduction of the endoscope if the patient experiences nausea during the study.

• In the direct laryngoscopy the patient must enter in a hospital facility. The exploration is performed in an operating room with the use of general anesthesia and the use of instruments that are placed directly in the larynx.
• The study by lIndirect aringoscopy usually takes a few minutes, the study by direct laryngoscopy can last 45-60 minutes.

Preparation for the study

• In indirect laryngoscopy no prior preparation is required by the patient, although it may be recommended to avoid drinking liquids and or solids a few hours prior to the study.
• In indirect laryngoscopy prior preparation by the patient is required Since general anesthesia must be used, the type of preparation must be communicated to the patient prior to its performance.

What does it feel like during and after the study?

• The Flexible fibroscopy is painless for the patient, the passage of the endoscope may be felt, but these are generally mild discomfort. nausea may occur in some cases which can be avoided with the use of a local anesthetic spray.
• The telelaryngoscopy is painless for the patient, the passage of the endoscope can be felt, but in general they are mild-moderate discomfort. nausea can occur in most cases and can be avoided with the use of a local anesthetic spray.
• The Direct laryngoscopy requires the use of general anesthesia. In explorations in which the use of local anesthesia is necessary, the patient should avoid the intake of liquids and / or solids until the effect of the anesthetic has disappeared (about 30-45 minutes) to avoid the passage of liquid and / or food to the respiratory tree.

Study risks

During the study may appear:     

• Allergy to the drug (anesthetic) used during the examination.
• Mild-moderate nasopharyngeal irritation
• Bronchial aspiration (rare)     

Study contraindications

The patient should consult with his doctor before carrying out the study in case of:

• Taking or using blood thinners

What is the study done for?

The study by laryngoscopy is a relatively simple and safe technique widely used in the field of Otorhinolaryngology and Phoniatrics since it offers very useful information for the doctor since it allows to detect the causes of an alteration of the fundamental functions of the larynx and of the vocal cords such as phonation, vocalization and passage of air flow.

At the same time it is used for the study of symptoms such as persistent cough, snoring, difficulty in passing air into the lungs, bad breath, among others. It allows the identification and extraction of foreign bodies located in the larynx and / or vocal cords. It allows to detect and / or diagnose inflammatory, infectious processes, such as laryngotracheitis and / or tumor that affect the larynx and / or the vocal cords.