What is stroboscopy?
Laryngeal stroboscopy is a study of vocal fold vibration. This test is performed when there are diagnostic doubts in vocal fold lesions. It is characterized by allowing to visualize the mucosal surface around the vocal folds and to diagnose small alterations in the vibration not perceptible by other techniques.
What does stroboscopy consist of?
There are two types of stroboscopy depending on the endoscope used:
- Stroboscopy with flexible endoscope: it consists of introducing the endoscope through one of the nostrils until it is placed in the larynx. Once it is in place, the patient, who is seated in an armchair with his head forward and his chin slightly tilted downwards, must perform actions such as speaking or whistling in order to study the functions of the larynx and vocal cords. This method does not require sedatives or anesthetics.
- Stroboscopy with rigid endoscope: consists of introducing the endoscope through the mouth, holding the patient’s tongue with sterile gauze to make placement easier. As in the previous technique, the patient is seated and must speak when asked to do so by the specialist. In the event that the patient is nauseated during the study, a pre-anesthetic can be used.
Why is stroboscopy performed?
This test is performed especially in cases of dysphonia to diagnose small alterations in the vibration of the vocal cords.
Preparation for stroboscopy
No previous preparation is required, although, if the patient takes anticoagulants, he/she should consult with the specialist before performing the study.
What does it feel like during the exam?
The study is painless, although some patients may have some discomfort in the larynx or nausea during the placement of the endoscope. Once the study has been performed, some discomfort or irritation of the nose or larynx may appear, which will disappear after a few hours or with the intake of an anti-inflammatory drug.
Meaning of abnormal stroboscopy results
The results obtained are very useful in cases of dysphonia, both functional and organic, since it diagnoses small lesions such as nodules, polyps, small tumor lesions, chordal sulcus, cysts or infectious lesions. In addition, it can report the fundamental frequency of vocal fold vibration, i.e. determine whether the voice is too deep or too high-pitched depending on the sex of the patient.