Discussion:
GlideScope ® is a video laryngoscope instrument that is primarily used
for oral endotracheal intubation(5). It provides
optimal glottic views and it is this benefit that can be directly
translated into our patients to provide a good view of the neopharynx.
The main benefit with this is that it allows for an optimal view without
the need for substantial neck extension (figure 2), which is very
difficult to achieve in patients with extensive post-radiotherapy
fibrosis.
Usually, video fluoroscopy-guided Botox injections are performed.
However, in some patients injections are required under general
anaesthetic, which has the advantage of excellent visual control and
minimal risk to blood vessels or surrounding
muscles.(4) Usually a view of the neopharynx is then
achieved with a rigid pharyngoscope, but in those with short necks or
cervical spine pathologies, it is difficult to extend the neck to allow
a good view and provide access. Video fluoroscopy may not be available
in a resource-limited setting and requires a radiographer and the Speech
and Language therapist to be present. There is the added risk of
radiation exposure, particularly if these patients require repeat
procedures.
Rigid instruments such as pharyngoscopes and
oesophagoscopes(4) are used to directly visualise and
inject the Botox. However, it is challenging to use rigid instruments in
patients with limited neck extension, these further carry a risk of
perforation to the surrounding tissue, something that does not exist
with the GlideScope. Furthermore, video-laryngoscopy carries a
significantly lower risk of aerosol-generation and transmission compared
to direct laryngoscopies(6), an issue that is topical
in the COVID-19 pandemic.
The GlideScope ® can also provide direct vision of the neopharynx where
this is impossible with a rigid instrument to enable accurate placement
of dilation balloons or to ensure the safe passing of bougies and has
been used by the authors for this purpose.