Endoscopic diagnosis of upper respiratory tract
Endoscopes are the optical systems which allow for viewing those parts of the body which are inaccessible for direct visual assessment.
In the case of the upper airway, endoscopy is a particularly useful method in diagnostics of diseases of the nose and paranasal sinuses, nasal part of the throat (nasopharynx), larynx and lower pharynx.Optical system may be based on the system of lenses enclosed in a rigid metal tube (so-called rigid endoscope) or may use a bundle of optical fibres forming the flexible tube (so-called flexible endoscope = fiberscope). The diameter of both systems is similar and usually amounts from 2.7 mm to 4 mm. The advantage of rigid endoscopes is an excellent image quality, whereas their disadvantage includes impossibility to adjust to natural curvatures of the respiratory tract and as a consequence limited access to some regions. Flexible endoscopes produce only a slightly poorer image quality but they move painlessly through all curvatures. Therefore, during one examination one can view each element of the upper respiratory tract from the nasal cavity, through nasopharynx and mesopharynx to larynx and lower pharynx (nasopharyngoscopy).
Indications for the examination:
Examination of the nasopharynx with use of fiberscope is mainly indicated in children with suspected adenoid hypertrophy (so-called enlarged adenoid). The symptoms of the overgrowth include: nasal obstruction, snoring, sleep apnoea, hearing impairment, nasal voice and persistent rhinitis. In adults, nasopharyngeal endoscopy is an essential part of diagnosing nasopharyngeal carcinoma, which may present with symptoms such as: neck tumour, unilateral hearing loss, nose bleeds, nasal congestion, ear pain, double vision.
Fiberoptic laryngoscopy and fiberscopy of laryngopharynx is indicated in patients with voice problems and/or swallowing disorders. This method is of particular importance in the case of patients who cannot undergo classic laryngeal mirror examination or cannot be examined with rigid endoscope. Such situation may be caused by specific anatomy or excessively high vomiting reflex.
Preparation and course of the procedure:
Nasopharyngoscopy does not require any special preparations from the patient. Examination is performed in a sitting position with head leant against the bolster of the laryngological examination chair. The procedure is painless and usually does not require anaesthesia. Nevertheless, in the case of children and adults with excessively high vomiting reflex and particularly sensitive, nasal and pharyngeal mucous membrane may be anaesthetised with lidocaine spray.
The assessment is conducted by otolaryngologist and usually lasts several minutes. During the test, there is a possibility to record obtained image in form of pictures or short films in the computer’s memory and to print pictures on a colour printer.
What information are obtained during the examination?
Nasopharyngoscopy allows to view all parts of the upper respiratory tract and assess in detail possible lesions observed there. This is a test which is more precise than radiological examination and allows to eliminate the necessity to irradiate a patient, which is of particular importance in the case of children and pregnant women. Endoscope is connected to the camera and computer and therefore obtain