Nasopharyngoscopy

Nasopharyngoscopy is a routine investigation for the assessment of velopharyngeal insufficiency. It is particularly good at visualising which structures are impaired but it gives little information as to structural size, or the degree and range of movement. The latter problems are largely due to optical distortion as a result of a wide and oblique viewing angle.

The endoscope may be rigid or flexible:

• rigid endoscopes:
  • better light carrying capacity
  • generally better optical resolution
  • difficult to pass if there is septal deviation
• flexible endoscopes:
  • easier to pass
  • less threatening to child patients
  • reduced light-carrying capacity so poorer views in larger nasopharynx

Before passage of the endoscope, the nasal cavity and nasopharynx need to be anaesthetized. This can be done with a local anaesthetic and vasoconstrictor spray eg:

• 5% lignocaine and 0.5% phenylephrine
• 3% cocaine and 0.25% adrenaline

Nasopharyngoscopy should be recorded for later assessment; combined with videofluoroscopy, it allows measurement of the extent of movement as the width of the 'scope is visible on radiographic views.