JCPSLP Vol 14 No 1 2012

21 / 60

JCPSLP Volume 14, Number 1 2012 19
reasonable amount of contrast needs to be swallowed for
these observations to be made. This may pose significant
risk to patients where secretion management is an issue.
function, with studies demonstrating its applications
for specific populations such as those suffering from
neurological disorders such as stroke (Seidl, Nusser-
Muller-Busch, Westhofen, & Ernst, 2008; Warnecke et al.,
2009a; Warnecke et al., 2009b), severe brain injury (Brady,
Pape, Darragh, & Escobar, 2009), neurodegenerative
and neuromuscular disorders (Coscarelli, Verrecchia, &
Coscarelli, 2007; Warnecke, Duning et al., 2010; Warnecke,
Oelenberg et al., 2010; Warnecke et al., 2008), recurrent
laryngeal nerve paralysis (Perie, Roubeau, & Lacau St Guily,
2003), and tracheostomy (Hales, Drinnan, & Wilson, 2008).
Different fields of view
The fields of view obtained via FEES and VFSS are very
different. Figure 1 shows a side-by-side comparison of the
typical field of view for VFSS and FEES.
Figure 1. Radiographic image taken in the lateral plane during
VFSS (left). Endoscopic image taken with endoscope positioned
in the oropharynx during FEES (right)
As shown, the field of view obtained via FEES enables
the surface anatomy of the pharyngeal and laryngeal
structures to be visualised. In this position, the movement
of these structures in response to swallowing can be
evaluated. There is a brief moment at the height of
the swallow when the visual image is interrupted due
to contact made between the objective lens of the
endoscope and surrounding tissue (Langmore, 2001;
Leder & Murray, 2008). Although many may argue that
this is a critical moment in a swallowing evaluation, and
that aspiration during the swallow cannot therefore be
observed, researchers have identified that aspiration during
the swallow occurs much less frequently than aspiration
before or after the swallow (Smith, Logemann, Colangela,
Rademaker, & Pauloski, 1999). Through the use of ionising
radiation, VFSS enables the submucosal structures of the
entire upper aerodigestive tract to be visualised while a
patient swallows a radio-opaque bolus. These views enable
the oral, pharyngeal, and upper oesophageal phases of
swallowing to be observed, including the dynamic interplay
between the various anatomical structures of this region
(Martin-Harris & Jones, 2008). These views enable the
movement of the bolus to be observed as it moves from the
oral cavity through the upper oesophageal sphincter.
FEES enables secretions to be directly visualised and the
management of these secretions to be evaluated without
the patient being required to ingest food/fluids, as shown
in Figure 2. Significant predictive relationships have been
identified between the presence of pharyngeal secretions
and aspiration (Donzelli, Brady, Wesling, & Craney, 2003;
Langmore et al., 1998; Linden, Kuhlmeier, & Patterson,
1993; Murray, Langmore, Ginsberg, & Dostie, 1996).
Accumulation of pharyngeal secretions can sometimes
be inferred with VFSS, when the ingested contrast-
laden material adheres to these secretions. However, a
Radiographic imaging via VFSS provides information
about how atypical submucosal structures such as cervical
osteophytes impact on swallowing function (Langmore,
2001). FEES provides a direct view of the surface anatomy
of the pharynx and larynx (Rugiu, 2007). This view enables
the impact of abnormal surface anatomy such as oedema,
mucositis, as well the effect of the presence or reduction
in oral secretions on swallowing function, to be examined.
Reduced saliva production, xerostomia, and inflammatory
processes has been found to be associated with an
increased incidence of pain and discomfort associated with
swallowing (Ku et al., 2006; Logemann et al., 2001; Wu,
Hsiao, Ko, & Hsu, 2000) and to negatively affect the ability
to satisfy nutritional requirements orally (Scully, Epstein, &
Sonis, 2003; Worthington et al., 2010).
Judgments regarding pharyngeal residue, or penetration
and aspiration can be influenced by the type of instrumental
swallowing examination used (Kelly, Drinnan, & Leslie,
2007; Kelly, Leslie, Beale, Payten, & Drinnan, 2006).
Researchers have shown that observers rate pharyngeal
residue, penetration, and aspiration as more impaired
when evaluating swallowing via FEES compared to ratings
made via VFSS (Kelly et al., 2007; Kelly et al., 2006). These
differences are likely to be associated with the indirect
versus direct nature of the images provided by VFSS
and FEES, respectively. Radiographic imaging provides
indirect views of the food/fluid bolus being swallowed, and
indirect information about the anatomy and physiology
of swallowing functions (Rugiu, 2007). In contrast, FEES
provides direct views of food/fluid bolus and residue within
the hypopharynx (Rugiu, 2007). Figure 3 attempts to
illustrate how the source of the visual images can affect the
judgements made about pharyngeal residue (Rugiu, 2007).
Although these images have not been taken from the same
patient, they still provide a useful comparison. The image
on the left is taken from a VFSS. This picture shows post
swallow residue localised mainly to the valleculae, with a
lesser amount in the pyriform fossae. The image on the
right is taken from a FEES. Similarly, it shows post swallow
residue localised mainly in the valleculae with a lesser
amount in the pyriform fossae.
Figure 2. Endoscopic view showing secretions throughout the
pharynx and larynx