Introduction: Examination
of nose has been revolutionised by the advent of nasal
endoscopes. These endoscopes are nothing but miniature
telescope. It comes in the following sizes 2.7mm, and
4mm. It comes in various angulations namely 0 degrees, 30
degrees, 45 degrees, and 70 degrees. The 2.7 mm endoscope is
used for diagnostic nasal endoscopy and in children. For
diagnostic nasal endoscopy it is better to use a 2.7 mm 30 degree
nasal endoscope if available. A 4mm 30 degree nasal
endoscope can also be used for diagnostic nasal endoscopy in
adults.
Procedure: Topical
anesthetic 4% xylocaine is used to anesthetise the nasal cavity
before the procedure. About 7 ml of 4% xylocaine is mixed with
10 drops of xylometazoline. Cotton pledgets are dipped in the
solution, squeezed dry and used to pack the nasal cavity.
Pledgets are packed in the inferior, middle and superior
meati. Packs are left in place for full 5 minutes.
Diagnostic endoscopy is performed using a 30 degree nasal
endoscope. If 2.7 mm scope is available it is preferred
because it can reach the smallest crevices of the nose.
4mm endoscope is sufficient to examine adult nasal
cavities.
First pass: In
this the endoscope is introduced along the floor of the nasal
cavity. Middle turbinate is the first structure to come into
view. Its superior attachment is studied. Inferior
surface of the middle turbinate is studied. As the endoscope
is slid posteriorly the adenoid tissue comes into view. On the
lateral surface of the nasopharynx the pharyngeal end of eustachean
tube can be identified. Its function can be assessed by asking
the patient to swallow. The endoscope is now turned 90 degrees
in the opposite direction, the uvula and soft palate comes into
view. The endoscope is again rotated by 90 degrees in the same
direction, the opposite side pharyngeal end of eustachean tube is
visualised. In this field both eustachean tubes become
visible.
